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2016年
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Numerical calculation of 3.8 μm and 1.55 μm laser radiation transmission characteristic under foggy condition
Zhang, Zeyu1, 2; Xie, Xiaoping1; Duan, Tao1; Wen, Yu3; Wang, Wei1 Source: Hongwai yu Jiguang Gongcheng/Infrared and Laser Engineering, v 45, May 25, 2016; Language: Chinese
; ISSN: 10072276; DOI: 10.3788/IRLA201645.S104007; Article number: S104007;
Publisher: Chinese Society of AstronauticsAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China2 University of Chinese Academy of Sciences, Beijing; 100049, China3 Xi'an Communication College, Xi'an; 710106, China
Abstract: Fog is an inevitable weather factor affecting the performance of free space optical communication. Selecting the appropriate laser wavelength can effectively reduce the influence. Three atmospheric visibility of mist, fog, haze were considered in this paper. The transmission characteristic of mid-wave IR wavelength at 3.8 μm was compared with the traditional near-infrared wavelength at 1.55 μm that both belong to atmospheric transmission windows. Using Monte Carlo method, the propagation of a large number of photons along the horizontal direction was numerically simulated. Relationship between the relative light intensity and different receiving surface radius, photon transmittance under different transmission distance and different atmospheric visibility were worked out. The result reveals that the mid- wave IR wavelength at 3.8 μm, the light intensity is more concentrated under the same radius of receiving surface, and photon transmission is higher under the same propagation distance and less affected by atmospheric visibility. The wavelength at 3.8 μm is more suitable for horizontal link of free space optical communication in the fog than 1.55 μm. © 2016, Editorial Board of Journal of Infrared and Laser Engineering. All right reserved. (15 refs.)Main Heading: Optical communicationControlled terms: Fog - Infrared devices - Light - Monte Carlo methods - Photons - VisibilityUncontrolled terms: Atmospheric scattering - Atmospheric transmissions - Free Space Optical communication - Mid-wave IR - Near-infrared wavelength - Russian roulette - Transmission characteristics - Transmission distancesClassification Code: 443.1 Atmospheric PropertiesAtmospheric Properties - 717.1 Optical Communication SystemsOptical Communication Systems - 741.1 Light/OpticsLight/Optics - 741.2 VisionVision - 922.2 Mathematical StatisticsMathematical Statistics - 931.3 Atomic and Molecular PhysicsAtomic and Molecular Physics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


High-Quality Hollow Closed-Pore Silica Antireflection Coatings Based on Styrene-Acrylate Emulsion @ Organic-Inorganic Silica Precursor
Guo, Zhaolong1, 2; Zhao, Haixin1; Zhao, Wei1; Wang, Tao1; Kong, Depeng1; Chen, Taojing1; Zhang, Xiaoyan1 Source: ACS Applied Materials and Interfaces, v 8, n 18, p 11796-11805, May 11, 2016
; ISSN: 19448244, E-ISSN: 19448252; DOI: 10.1021/acsami.6b02192;
Publisher: American Chemical SocietyAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China2 University of Chinese Academy of Sciences, Beijing; 100049, China
Abstract: Making use of a facile and low-cost way for the preparation of a hierarchically organized novel hollow closed-pore silica antireflective coating (CHAR) with tailored optical properties and a mechanical reliability is of great interest in the field of solar photovoltaic technology. The process mainly contains two aspects: (1) a styrene-acrylate emulsion @ organic-inorganic silica precursor (SA@OISP) core/shell hierarchical nanostructure, consisting of a sacrificial styrene-acrylate (SA) primary template, was fabricated using a sol-gel method; (2) the self-assembly of the nanostructures leads to SA@OISP nanospheres forming the high-quality hollow closed-pore silica antireflection coating (CHAR) by a dip-coating process and a subsequent calcination treatment. The resulting SA@OISP nanospheres have a mean diameter of 65.2 nm and contained a SA soft core with a mean diameter of approximately 54.8 nm and an organic-inorganic silica precursor (OISP) shell with a thickness of approximately 6-10 nm. Furthermore, the prepared CHAR film exhibited a high transmittance and good ruggedness. An average transmittance (TAV) of 97.64% was obtained, and the value is close to the ideal single-layered antireflection coating (98.09%) over a broad range of wavelengths (from 380 to 1100 nm). The CHAR film showed a stable TAV, with attenuation values of less than 0.8% and 0.43% after the abrasion test and the damp heat test, respectively. The conversion efficiency of the CHAR coating cover solar modules tends to be increased by 3.75%. The promising results obtained in this study suggest that the CHAR film was considered as an essential component of the solar module and were expected to provide additional solar energy harvest under extreme outdoor climates. © 2016 American Chemical Society. (49 refs.)Main Heading: Antireflection coatingsControlled terms: Coatings - Emulsification - Film preparation - Inorganic coatings - Nanospheres - Nanostructures - Optical properties - Porous materials - Self assembly - Silica - Sol-gel process - Sol-gels - Solar cell arrays - Solar energy - Solar power generation - StyreneUncontrolled terms: Anti reflective coatings - Calcination treatment - Closed pore - Hierarchical Nanostructures - Mechanical reliability - Solar module - Solar photovoltaic technology - Styrene-acrylate emulsionsClassification Code: 615.2 Solar PowerSolar Power - 657.1 Solar Energy and PhenomenaSolar Energy and Phenomena - 702.3 Solar CellsSolar Cells - 741.1 Light/OpticsLight/Optics - 761 NanotechnologyNanotechnology - 802.3 Chemical OperationsChemical Operations - 804 Chemical Products GenerallyChemical Products Generally - 804.1 Organic CompoundsOrganic Compounds - 812.3 GlassGlass - 813.2 Coating MaterialsCoating Materials - 933 Solid State PhysicsSolid State Physics - 951 Materials ScienceMaterials Science
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Identification of high explosive RDX using terahertz imaging and spectral fingerprints
Liu, Jia1, 2; Fan, Wen-Hui1; Chen, Xu1, 2; Xie, Jun1, 2 Source: Journal of Physics: Conference Series, v 680, n 1, February 3, 2016, 5th International Conference on Advances in Optoelectronics and Micro/Nano-Optics, AOM 2015
; ISSN: 17426588, E-ISSN: 17426596; DOI: 10.1088/1742-6596/680/1/012030; Article number: 012030; Conference: 5th International Conference on Advances in Optoelectronics and Micro/Nano-Optics, AOM 2015, October 28, 2015 - October 31, 2015;
Publisher: Institute of Physics PublishingAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, China2 Graduate University of Chinese Academy of Sciences, Beijing, China
Abstract: We experimentally investigated the spectral fingerprints of high explosive cyclo-1,3,5- trimethylene-2,4,6-trinitramine (RDX) in terahertz frequency region. A home-made terahertz time-domain spectroscopy ranging from 0.2 THz-; 3.4 THz was deployed. Furthermore, two sample pellets (RDX pellet and polyethylene pellet), which were concealed in an opaque envelop, could be identified by using terahertz pulse imaging system. For the purpose of distinguishing the RDX between two pellets, we further calculated the THz frequency -domain map using its spectral fingerprints. It is demonstrated that the high explosive RDX could similarly be identified using terahertz frequency-domain imaging. (27 refs.)Main Heading: Terahertz spectroscopyControlled terms: Explosives - Frequency domain analysis - Optoelectronic devices - Pelletizing - Polyethylenes - Terahertz wavesUncontrolled terms: High explosives - Polyethylene pellets - Spectral fingerprints - Terahertz frequencies - Terahertz imaging - Terahertz pulse - Terahertz time domain spectroscopy - THz frequenciesClassification Code: 711 Electromagnetic WavesElectromagnetic Waves - 741.3 Optical Devices and SystemsOptical Devices and Systems - 815.1.1 Organic PolymersOrganic Polymers - 921.3 Mathematical TransformationsMathematical Transformations - 931.1 MechanicsMechanics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Near infrared quantum cutting of Tb3+-Yb3+co-doped CeF3nanophosphors
Sun, Xiao1; Hu, Xiao-Yun1, 2; Hou, Wen-Qian3; Fan, Jun3; Miao, Hui1; Zhan, Su-Chang1 Source: Journal of Nanoscience and Nanotechnology, v 16, n 4, p 3577-3582, April 2016
; ISSN: 15334880, E-ISSN: 15334899; DOI: 10.1166/jnn.2016.11880;
Publisher: American Scientific PublishersAuthor affiliation: 1 School of Physics, Northwest University, 710069, China2 State Key Laboratory of Transient Optics and Technology, Xi'an Institute of Optics and Precision Materials, Chinese Academy of Science, Xi'an; 710068, China3 School of Chemical Engineering, Xi'an; 710069, China
Abstract: In this paper, Tb3+-Yb3+Co-doped CeF3nanophosphors were synthesized using the microwave-assisted heating hydrothermal method (M-H). The excitation and emission spectra of the samples at room temperature show that the samples absorb ultraviolet light from 250 nm to 280 nm, and emit light at 300 nm. This corresponds to the transitions from5D to4F of Ce3+, 480 nm, 540 nm, 583 nm, 620 nm which correspond to the transitions from5D4to7F6, 5, 4, 3of Tb3+, 973 nm which corresponds to the transitions from2F5/2-2F7/2of Yb3+. In the emission spectra, it is clear that the emission intensity of Ce3+and Tb3+decreases, and Yb3+increases with increasing Yb3+. This suggests that energy transfer from Ce3+to Yb3+, and Ce3+to Tb3+to Yb3+may occur. In the near infrared emission area, it is noted that a distinct emission centered at 973 nm was observed under 260 nm excitation. This is due to transitions among the different Stark levels of2FJ(J=5/2, 7/2)Yb3+ions. This also suggests an energy transfer from Ce3+ions to Tb3+and then to Yb3+. The energy transfers from Tb3+-Yb3+Co-doped CeF3nanophosphors, which lead to intense NIR emissions at 900-1050 nm, match the energy of Si band gaps of Si-based solar cells. Therefore, these kinds of materials are promising candidates for applications that require modifying if solar spectrums and enhancement of conversion efficiency of Si-based solar cells. Copyright © 2016 American Scientific Publishers All rights reserved. (10 refs.)Main Heading: Infrared devicesControlled terms: Emission spectroscopy - Energy gap - Energy transfer - Nanostructured materials - Silicon - Silicon solar cells - Solar cellsUncontrolled terms: CeF3 - Energy transfer mechanisms - Excitation and emission spectra - Microwave assisted heating - Nanophosphors - Near Infrared - Near-infrared emissions - Si-based solar cellsClassification Code: 549.3 Nonferrous Metals and Alloys excluding Alkali and Alkaline Earth Metals Nonferrous Metals and Alloys excluding Alkali and Alkaline Earth Metals - 702.3 Solar CellsSolar Cells - 761 NanotechnologyNanotechnology
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Influence of Driving Frequency on the Argon Dielectric Barrier Discharge Excited by Gaussian Voltage at Atmospheric Pressure
Xu, Yonggang1, 2; Jiang, Weiman2; Tang, Jie2; Zhu, Sha2; Wang, Yishan2; Li, Yongfang1; Zhao, Wei2; Duan, Yixiang2, 3 Source: IEEE Transactions on Plasma Science, v 44, n 11, p 2553-2563, November 2016
; ISSN: 00933813; DOI: 10.1109/TPS.2016.2572733; Article number: 7494657;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 School of Physics and Information Technology, Shaanxi Normal University, Xi'an; 710062, China2 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China3 Research Center of Analytical Instrumentation, Sichuan University, Chengdu; 610064, China
Abstract: A 1-D self-consistent fluid model was employed to investigate the effect of driving frequency on the discharge characters of a dielectric barrier discharge at atmospheric pressure in argon excited by a periodic Gaussian voltage. The simulation results indicate that there are two discharge modes: 1) Townsend and 2) glow modes in the multipulse discharge and different transitions between them during the discharge take place with the increase in driving frequency. When the driving frequency is 1 kHz, there is a tendency of transition from the Townsend mode through glow and finally back to the Townsend one during the positive half-circle of applied Gaussian voltage. However, the discharge in the half-circle can all along operate in the glow mode with the higher driving frequency. Moreover, when the driving frequency is sufficiently high, there are also distinct fluctuations of spatial performance of the charge densities in the positive column during the glow discharge. This is caused by the fact that a lot of charged particles created in the gas gap have not enough time to drift and diffuse to the dielectric barriers, and then these particles are preserved in the local discharge gap at such a high frequency. A comparison of the spatial and temporal evolutions of the electron density at different driving frequencies indicates that the increase in the driving frequency can enhance the plasma chemistry and also expand its volume. © 2016 IEEE. (37 refs.)Main Heading: Dielectric materialsControlled terms: Atmospheric chemistry - Atmospheric pressure - Charged particles - Dielectric devices - Flow control - Gaussian distribution - Glow dischargesUncontrolled terms: Dielectric barrier - Dielectric barrier discharges - Driving frequencies - High frequency HF - Plasma chemistries - Positive column - Spatial performance - Temporal evolution
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Infrared small target and background separation via column-wise weighted robust principal component analysis
Dai, Yimian1; Wu, Yiquan1, 2, 3, 4; Song, Yu1 Source: Infrared Physics and Technology, v 77, p 421-427, July 1, 2016
; ISSN: 13504495; DOI: 10.1016/j.infrared.2016.06.021;
Publisher: Elsevier B.V.Author affiliation: 1 College of Electronic and Information Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing; 211106, China2 Key Laboratory of Spectral Imaging Technology CAS, Xi'an Institute of Optics and Precision Mechanics of CAS, Xi'an; 710000, China3 State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu; 610500, China4 State Key Laboratory of Marine Geology, Tongji University, Shanghai; 200092, China
Abstract: When facing extremely complex infrared background, due to the defect of l1norm based sparsity measure, the state-of-the-art infrared patch-image (IPI) model would be in a dilemma where either the dim targets are over-shrinked in the separation or the strong cloud edges remains in the target image. In order to suppress the strong edges while preserving the dim targets, a weighted infrared patch-image (WIPI) model is proposed, incorporating structural prior information into the process of infrared small target and background separation. Instead of adopting a global weight, we allocate adaptive weight to each column of the target patch-image according to its patch structure. Then the proposed WIPI model is converted to a column-wise weighted robust principal component analysis (CWRPCA) problem. In addition, a target unlikelihood coefficient is designed based on the steering kernel, serving as the adaptive weight for each column. Finally, in order to solve the CWPRCA problem, a solution algorithm is developed based on Alternating Direction Method (ADM). Detailed experiment results demonstrate that the proposed method has a significant improvement over the other nine classical or state-of-the-art methods in terms of subjective visual quality, quantitative evaluation indexes and convergence rate. © 2016 Elsevier B.V. (42 refs.)Main Heading: Principal component analysisControlled terms: Image processing - Infrared imaging - Quality control - SeparationUncontrolled terms: Alternating direction methods - Image modeling - Infrared small targets - Quantitative evaluation - Robust principal component analysis - Solution algorithms - State-of-the-art methods - Target and backgroundClassification Code: 746 Imaging TechniquesImaging Techniques - 802.3 Chemical OperationsChemical Operations - 913.3 Quality Assurance and ControlQuality Assurance and Control - 922.2 Mathematical StatisticsMathematical Statistics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Optimization design of two-dimensional magneto optical trap field coils for cold atom interferometer
Fan, Pengge1, 2; Wu, Yiming1; Jia, Sen1; Wang, Xianhua1 Source: Hongwai yu Jiguang Gongcheng/Infrared and Laser Engineering, v 45, n 6, June 25, 2016; Language: Chinese
; ISSN: 10072276; DOI: 10.3788/IRLA201645.0618003; Article number: 0618003;
Publisher: Chinese Society of AstronauticsAuthor affiliation: 1 Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China2 University of Chinese Academy of Sciences, Beijing; 100049, China
Abstract: High flux of cold atoms is one of the key technologies to realize high-precision cold atom interferometer. The approach of concatenation of two-dimensional Magnetic Optical Trap (2D-MOT) and three-dimensional Magnetic Optical Trap (3D-MOT) is generally used to obtain high flux of cold atoms. The magnetic field distribution of 2D-MOT is the key influencing factor in this appliance. In this paper, three different(rectangular, race-track and saddle) mathematical models of Anti-Helmholtz coils in 2D-MOT were established to analyze the magnetic field distribution. Then, the magnetic field zero drift and the change of magnetic field gradient caused by the error of eccentricity, coils asymmetry, parallelism and inside diameter asymmetry were analyzed, which were produced in the manufacture and installation process using finite element analysis. Results show that the magnetic field gradient provided by saddle coils is more conducive to produce high flux of cold atoms when eccentricity error is less than 1.14 mm, coils asymmetry error is less than 0.016 A and parallelism error is less than 1.02°. This work may provide theoretical guidance for the design and fabrication of magnetic system of 2D-MOT of cold atom interferometer. © 2016, Editorial Board of Journal of Infrared and Laser Engineering. All right reserved. (10 refs.)Main Heading: Finite element methodControlled terms: Atoms - Errors - Interferometers - Magnetic fields - MagnetismUncontrolled terms: Cold atoms - Helmholtz coil - Key influencing factors - Magnetic field distribution - Magnetic field gradient - Magnetooptical traps - Optical trap - Optimization designClassification Code: 701.2 Magnetism: Basic Concepts and PhenomenaMagnetism: Basic Concepts and Phenomena - 921.6 Numerical MethodsNumerical Methods - 931.3 Atomic and Molecular PhysicsAtomic and Molecular Physics - 941.3 Optical InstrumentsOptical Instruments
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


The influence of thermal and free carrier dispersion effects on all-optical wavelength conversion in a silicon racetrack-shaped microring resonator
Wang, Zhaolu1; Liu, Hongjun1; Sun, Qibing1; Huang, Nan1; Li, Shaopeng1; Han, Jing1 Source: Laser Physics, v 26, n 7, July 2016
; ISSN: 1054660X, E-ISSN: 15556611; DOI: 10.1088/1054-660X/26/7/075403; Article number: 075403;
Publisher: Institute of Physics PublishingAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Opticsand Precision Mechanics, Chinese Academy of Science (CAS), Xi'an; 710119, China
Abstract: We experimentally demonstrate ultra-low pump power wavelength conversion based on four-wave mixing in a silicon racetrack-shaped microring resonator. When the pump and signal are located at the resonance wavelengths, wavelength conversion with a pump power of only 1 mW can be realized in this microring resonator because of the resonant enhancement of the device. However, saturation of the conversion efficiency occurs because of the shift of the resonance peak, which is caused by the change of the effective refractive index induced by a combination of thermal and free carrier dispersion effects, and it is demonstrated that the thermal effect is the leading-order factor for the change of the refractive index. The maximum conversion efficiency of -21 dB is obtained when the pump power is less than 12 mW. This ultra-low-power on-chip wavelength convertor based on a silicon microring resonator can find important potential applications in highly integrated optical circuits for all-optical signal processing. © 2016 Astro Ltd. (26 refs.)Main Heading: Dispersion (waves)Controlled terms: Conversion efficiency - Efficiency - Four wave mixing - Low power electronics - Optical frequency conversion - Optical resonators - Optical signal processing - Refractive index - Resonators - Signal processing - Silicon - Thermal effectsUncontrolled terms: All-optical signal processing - All-optical wavelength conversion - Effective refractive index - Free carriers - Integrated optical circuit - Resonance wavelengths - Resonant enhancements - Silicon microring resonatorsClassification Code: 525.5 Energy Conversion IssuesEnergy Conversion Issues - 549.3 Nonferrous Metals and Alloys excluding Alkali and Alkaline Earth Metals Nonferrous Metals and Alloys excluding Alkali and Alkaline Earth Metals - 641 Heat and Mass Transfer; ThermodynamicsHeat and Mass Transfer; Thermodynamics - 716.1 Information Theory and Signal ProcessingInformation Theory and Signal Processing - 741 Light, Optics and Optical DevicesLight, Optics and Optical Devices - 913.1 Production EngineeringProduction Engineering - 951 Materials ScienceMaterials Science
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


An improved acute lymphoblastic leukemia image segmentation scheme based on HSV color space
Li, Yan1, 2; Zhu, Rui1; Mi, Lei1; Cao, Yihui1, 2; Yao, Di3 Source: ICIC Express Letters, Part B: Applications, v 7, n 9, p 1983-1989, September 1, 2016
; ISSN: 21852766;
Publisher: ICIC Express Letters OfficeAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics Technology, Xi’an Institute of Optics, Precision Mechanics of Chinese Academy of Sciences, No. 17, Xinxi Road, New Industrial Park, Xi’an; 710119, China2 University of Chinese Academy of Sciences, No. 19, Yuquan Rd., Shijingshan District, Beijing; 100049, China3 Shenzhen Vivolight Medical Device and Technology Co. Ltd, Shenzhen; 518000, China
Abstract: In this paper, an improved HSV color space based Acute Lymphoblastic Leukemia (ALL) image segmentation scheme is proposed to improve accuracy of segmentation on digital microscope color images, especially for those taken in non-uniform background illumination conditions and by a microscope with different magnifications. The proposed method has several steps including contrast stretching, color space transformation, threshold segmentation, morphological operations and median filtering. Adopting two thresholds is the innovation of this work. For performance evaluation, 260 ALL blood cell images from ALL IDB2-a public and free available blood sample dataset are used. The experimental results show the proposed method gets a higher accuracy in segmenting both high- and low- contrast blood cell images than the original HSV color space based single threshold method, showing a better prospect in subsequent automatic acute lymphoblastic leukemia feature extraction and classification. © 2016 ICIC International. (29 refs.)Main Heading: Image segmentationControlled terms: Blood - Cells - Color - Color image processing - Digital devices - Diseases - Feature extraction - Image processing - Mathematical morphology - Median filtersUncontrolled terms: Acute lymphoblastic leukemia - Background illumination - Color space transformation - Feature extraction and classification - HSV color spaces - Morphological operations - Threshold segmentation - White blood cellsClassification Code: 461.2 Biological Materials and Tissue EngineeringBiological Materials and Tissue Engineering - 703.2 Electric FiltersElectric Filters - 741.1 Light/OpticsLight/Optics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Aberration correction for stimulated emission depletion microscopy with coherent optical adaptive technique
Yan, Wei1, 2; Yang, Yanlong3; Li, Yang2; Peng, Xiao1; Lin, Danying1; Qu, Junle1; Ye, Tong2 Source: Progress in Biomedical Optics and Imaging - Proceedings of SPIE, v 9717, 2016, Adaptive Optics and Wavefront Control for Biological Systems II
; ISSN: 16057422; ISBN-13: 9781628419511; DOI: 10.1117/12.2211907; Article number: 97170K; Conference: Adaptive Optics and Wavefront Control for Biological Systems II, February 13, 2016 - February 15, 2016; Sponsor: The Society of Photo-Optical Instrumentation Engineers (SPIE);
Publisher: SPIEAuthor affiliation: 1 Key Laboratory of Optoelectronic Devices and Systems, College of Optoelectronic Engineering, Shenzhen University, Shenzhen; 518060, China2 Department of Bioengineering, Clemson University, MUSC Bioengineering Program, Charleston; SC; 29425, United States3 State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Science, Xian; 710119, China
Abstract: Stimulated emission depletion microscopy (STED) has become one of the powerful research tools in the field of superresolution microscopy. As its spatial resolution is gained by phase modulation of the light field, the aberrations produced by optical systems and specimens may have negative impact on the focusing properties of two beams, especially the STED beam, resulting in reduced spatial resolution. In thick samples, the aberration effect may play an even more critical role in affecting spatial resolution. Here, we report our recent effort in correcting the aberration in STED microscopy by using coherent optical adaptive technique (COAT) so that the resolution can be improved. © 2016 SPIE. (12 refs.)Main Heading: Adaptive opticsControlled terms: Adaptive control systems - Biological systems - Image resolution - Light - Light modulators - Phase modulation - Stimulated emission - WavefrontsUncontrolled terms: Aberration correction - Adaptive technique - Focusing properties - Spatial light modulators - Spatial resolution - STED microscopies - Stimulated emission depletion microscopy - Super-resolution microscopyClassification Code: 461.9 BiologyBiology - 711 Electromagnetic WavesElectromagnetic Waves - 731.1 Control SystemsControl Systems - 741.1 Light/OpticsLight/Optics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Optical Bloch oscillations and Zener tunneling of Airy beams in ionic-type photonic lattices
Xiao, Fajun1; Zhu, Weiren2; Shang, Wuyun1; Wang, Meirong1; Zhang, Peng4; Liu, Sheng1; Premaratne, Malin3; Zhao, Jianlin1 Source: Optics Express, v 24, n 16, p 18332-18339, August 8, 2016; E-ISSN: 10944087; DOI: 10.1364/OE.24.018344;
Publisher: OSA - The Optical SocietyAuthor affiliation: 1 Key Laboratory of Space Applied Physics and Chemistry, Ministry of Education, Shaanxi Key Laboratory of Optical Information Technology, School of Science, Northwestern Polytechnical University, Xi'an; 710129, China2 Department of Electronic Engineering, Shanghai Jiao Tong University, Shanghai; 200240, China3 Advanced Computing and Simulation Laboratory (AχL), Department of Electrical and Computer Systems Engineering, Monash University, Clayton; VIC; 3800, Australia4 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China
Abstract: We report on the existence of optical Bloch oscillations (OBOs) and Zener tunneling (ZT) of Airy beams in ionic-type photonic lattices with a refractive index ramp. Different from their counterparts in uniform lattices, Airy beams undergoing OBOs show an alternatively switched concave and convex trajectory as well as a periodical revival of input beam profiles. Moreover, the ionic-type photonic lattice established in photorefractive crystal exhibits a reconfigurable lattice structure, which provides a flexible way to tune the amplitude and period of the OBOs. Remarkably, it is demonstrated that the band gap of the lattice can be readily controlled by rotating the lattice inducing beam, which forces the ZT rate to follow two significant different decay curves amidst decreasing index gradient. Our results open up new possibilities for all-optical switching, routing and manipulation of Airy beams. © 2016 Optical Society of America. (38 refs.)Main Heading: Optical latticesControlled terms: Crystal structure - Energy gap - Optical switches - Photonics - Photorefractive crystals - Refractive indexUncontrolled terms: Airy beams - All-optical switching - Beam profiles - Bloch oscillations - Decay curves - Lattice structures - Reconfigurable - Zener tunnelingClassification Code: 741 Light, Optics and Optical DevicesLight, Optics and Optical Devices - 744.8 Laser Beam InteractionsLaser Beam Interactions - 933.1.1 Crystal LatticeCrystal Lattice
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Local structure learning in high resolution remote sensing image retrieval
Du, Zhongxiang1, 2; Li, Xuelong1; Lu, Xiaoqiang1 Source: Neurocomputing, v 207, p 813-822, 26 September 2016
; ISSN: 09252312, E-ISSN: 18728286; DOI: 10.1016/j.neucom.2016.05.061;
Publisher: Elsevier B.V.Author affiliation: 1 Center for OPTical IMagery Analysis and Learning (OPTIMAL), State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; Shaanxi; 710119, China2 University of the Chinese Academy of Sciences, 19A Yuquanlu, Beijing; 100049, China
Abstract: High resolution remote sensing image captured by the satellites or the aircraft is of great help for military and civilian applications. In recent years, with an increasing amount of high resolution remote sensing images, it becomes more and more urgent to find a way to retrieve them. In this case, a few methods based on the statistical information of the local features are proposed, which have achieved good performances. However, most of the methods do not take the topological structure of the features into account. In this paper, we propose a new method to represent these images, by taking the structural information into consideration. The main contributions of this paper include: (1) mapping the features into a manifold space by a Lipschitz smooth function to enhance the representation ability of the features; (2) training an anchor set with several regularization constrains to get the intrinsic manifold structure. In the experiments, the method is applied to two challenging remote sensing image datasets: UC Merced land use dataset and Sydney dataset. Compared to the state-of-the-art approaches, the proposed method can achieve a more robust and commendable performance. © 2016 Elsevier B.V. (38 refs.)Main Heading: Image retrievalControlled terms: Image reconstruction - Land use - Military applications - Military photography - Remote sensing - Space optics - Training aircraftUncontrolled terms: High resolution remote sensing images - Lipschitz - Manifold structures - Remote sensing images - State-of-the-art approach - Statistical information - Structural information - Topological structure
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Frequency comb generation in the green using silicon nitride microresonators
Wang, Leiran1, 2; Chang, Lin1; Volet, Nicolas1; Pfeiffer, Martin H. P.3; Zervas, Michael3; Guo, Hairun3; Kippenberg, Tobias J.3; Bowers, John E.1 Source: Laser and Photonics Reviews, v 10, n 4, p 631-638, July 1, 2016
; ISSN: 18638880, E-ISSN: 18638899; DOI: 10.1002/lpor.201600006;
Publisher: Wiley-VCH VerlagAuthor affiliation: 1 Department of Electrical and Computer Engineering, University of California, Santa Barbara (UCSB); CA; 93106, United States2 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an 710119, China3 École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
Abstract: Optical frequency combs enable precision measurements in fundamental physics and have been applied to a growing number of applications, such as molecular spectroscopy, LIDAR and atmospheric trace-gas sensing. In recent years, the generation of frequency combs has been demonstrated in integrated microresonators. Extending their spectral range to the visible is generally hindered by strong normal material dispersion and scattering losses. In this paper, we report the first realization of a green-light frequency comb in integrated high-Q silicon nitride (SiN) ring microresonators. Third-order optical non-linearities are utilized to convert a near-infrared Kerr frequency comb to a broadband green light comb. The 1-THz frequency spacing infrared comb covers up to 2/3 of an octave, from 144 to 226 THz (or 1327-2082 nm), and the simultaneously generated green-light comb is centered around 570-580 THz (or 517-526 nm), with comb lines emitted down to 517 THz (or 580 nm) and up to 597 THz (or 502 nm). The green comb power is estimated to be as high as −9.1 dBm in the bus waveguide, with an on-chip conversion efficiency of −34 dB. The proposed approach substantiates the feasibility of on-chip optical frequency comb generation expanding to the green spectral region or even shorter wavelengths. (Figure presented.) . © 2016 by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim (30 refs.)Main Heading: Optical frequency conversionControlled terms: Infrared devices - Molecular spectroscopy - Natural frequencies - Nitrides - Optical materials - Optical radar - Resonators - Silicon - Silicon nitrideUncontrolled terms: Atmospheric trace gas - Fundamental physics - Material dispersions - Optical frequency comb generation - Optical frequency combs - Optical nonlinearity - Precision measurement - Silicon nitride (SiN)
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Study on the deep neural network of intelligent image detection and the improvement of elastic momentum on image recognition
Yue, Qi1, 2; Ma, Caiwen1 Source: Journal of Computational and Theoretical Nanoscience, v 13, n 5, p 3326-3330, May 2016
; ISSN: 15461955, E-ISSN: 15461963; DOI: 10.1166/jctn.2016.4994;
Publisher: American Scientific PublishersAuthor affiliation: 1 Xi'an Institute of Optics and Precision Mechanic, Xi'an; 710119, China2 University of Chinese Academy of Sciences, Beijing; 100039, China
Abstract: Aiming at deep neural network of intelligent image detection, this paper proposes parameter learning method of exponential elastic momentum, applies this method in the pedestrian detection, the detection accuracy is 97.8%. In addition, this algorithm is compared with adaptive momentum methods, standard momentum gradient method and elastic momentum, and the accuracy obtained through this method increases by 2.6% and 6.5% on average respectively. Copyright © 2016 American Scientific Publishers All rights reserved. (13 refs.)Main Heading: MomentumControlled terms: Gradient methods - Image recognition - Object recognition - Target trackingUncontrolled terms: Deep neural networks - Detection accuracy - Image detection - Model optimization - Momentum method - Parameter learning - Pedestrian detectionClassification Code: 921.6 Numerical MethodsNumerical Methods - 931.1 MechanicsMechanics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


WS2/fluorine mica (FM) saturable absorber for high power optical pulse formation
Li, L.1, 2; Wang, Z.F.2; Wang, Y.G.2; Wang, X.2; Yang, G.W.2 Source: Optik, v 127, n 21, p 10223-10227, November 1, 2016
; ISSN: 00304026; DOI: 10.1016/j.ijleo.2016.08.040;
Publisher: Elsevier GmbHAuthor affiliation: 1 School of Science, Xi'an University of Posts and Telecommunications, Xi'an; 710121, China2 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China
Abstract: The report presents the high power mode-locking operation in an anomalous-dispersion fiber laser with a novel WS2saturable absorber (SA) based on fluorine mica (FM) substrate. Compared to organic host material such as polymer, FM has higher softening temperature, heat dissipation and laser damage threshold. By employing the SA, a stable mode-locked fiber laser is achieved. The duration of the pulse broadens from 2.816 ns to 3.654 ns almost linearly with increasing pump power. The average output power and single pulse energy can increase up to 33.5 mW and 4 nJ at the maximum pump power respectively. The results indicate that WS2/FM material is an ideal SA for high power Er-doped fiber (EDF) lasers. © 2016 Elsevier GmbH (26 refs.)Main Heading: Mode-locked fiber lasersControlled terms: Dispersions - Fiber lasers - Fibers - Laser damage - Laser mode locking - Locks (fasteners) - Mica - Optical pumping - Organic lasers - Saturable absorbers - Silicate mineralsUncontrolled terms: Anomalous dispersion - Average output power - Er-doped fibers - High-power optical pulse - Laser damage threshold - Maximum pump power - Single pulse energy - Softening temperatureClassification Code: 482.2 MineralsMinerals - 744 LasersLasers - 951 Materials ScienceMaterials Science
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Terahertz emission dependence on the polarization angle between two-color lasers
Xie, Jun1, 2; Fan, Wen-Hui1; Tang, Jie1 Source: Guangzi Xuebao/Acta Photonica Sinica, v 45, n 10, October 1, 2016
; ISSN: 10044213; DOI: 10.3788/gzxb20164510.1030002; Article number: 1030002;
Publisher: Chinese Optical SocietyAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China2 University of Chinese Academy of Sciences, Beijing; 100049, China
Abstract: The influence of the polarization angle between two-color lasers on the Terahertz (THz) emission was investigated based on a modified two-dimensional transient current model. By changing the polarization angle between the fundamental frequency laser and its second harmonic laser beam, it is found that, the emitted THz amplitude varys periodically with the chaning of the polarization angle in laser plasma, and the optimal angle is also changed with the different laser intensity. Under the comparatively low laser intensity (≤2×1014W/cm2), the THz amplitude can reach the maximum when the two-color lasers have the same polarization. However, the optimal angle will increase with the increasing of the total laser intensity when the laser intensity is high enough(>2×1014W/cm2). The electron density was firstly used to analyze this phenomenon under comparatively low laser intensity and then the residual drift current was utilized to reveal the underlying physical mechanism. It was found that, the residual current density is the essential source of the THz waves and which can determine the intensity of THz emission © 2016, Science Press. All right reserved. (23 refs.)Main Heading: Terahertz wavesControlled terms: Color - Laser beams - Laser produced plasmas - Lasers - Plasma interactions - Plasmas - PolarizationUncontrolled terms: Fundamental frequencies - Intensity - Laser intensities - Physical mechanism - Polarization angle - Tera Hertz - Terahertz emissions - Two-dimensional transientClassification Code: 711 Electromagnetic WavesElectromagnetic Waves - 741.1 Light/OpticsLight/Optics - 744.1 Lasers, GeneralLasers, General - 744.8 Laser Beam InteractionsLaser Beam Interactions - 932.3 Plasma PhysicsPlasma Physics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Stable all-fiber Er-doped Q-switched laser with a WS2/fluorine mica (FM) saturable absorber
Li, Lu1, 2; Wang, Zhenfu2; Wang, Yonggang2; Wang, Xi2; Yang, Guowen2; Jiang, Shouzhen3 Source: Laser Physics, v 26, n 10, October 2016
; ISSN: 1054660X, E-ISSN: 15556611; DOI: 10.1088/1054-660X/26/10/105101; Article number: 105101;
Publisher: Institute of Physics PublishingAuthor affiliation: 1 School of Science, Xi'An University of Posts and Telecommunications, Xi'an; 710121, China2 State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China3 School of Physics and Electronics, Shandong Normal University, Jinan; 250014, China
Abstract: This paper presents a stable all-fiber Q-switched Er-doped fiber (EDF) laser with WS2/fluorine mica (FM) as the saturable absorber (SA). The SA device is obtained by depositing WS2nanosheet layers onto a 20 μm thick one-layer FM substrate using a thermal decomposition method. The modulation depth (MD) of the SA is 8.22% and the non-saturable loss (NL) is 16.38%. By inserting the SA into the EDF laser cavity, stable Q-switched operation is achieved with a central wavelength of 1567 nm. The repetition rate can be tuned from 20.98 kHz to 33.74 kHz and the pulse duration can be adjusted from 8.3 μs to 6.98 μs by increasing the pump power. The maximum output power and the maximum pulse energy are measured to be 2.07 mW and 61.4 nJ, respectively. The experimental results evidently show that the WS2/FM can be regarded as a high-performance SA for fiber lasers. © 2016 Astro Ltd. (37 refs.)Main Heading: Saturable absorbersControlled terms: Decomposition - Erbium - Fiber lasers - Fibers - Mica - Optical pumping - Pulse repetition rate - Q switched lasers - Q switching - Silicate mineralsUncontrolled terms: Central wavelength - Maximum output power - Modulation depth - Non-saturable loss - Q-switched - Q-switched operation - Repetition rate - Thermal decomposition methodsClassification Code: 482.2 MineralsMinerals - 547.2 Rare Earth MetalsRare Earth Metals - 744 LasersLasers - 802.2 Chemical ReactionsChemical Reactions
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Optically bound colloidal lattices in evanescent optical fields
Han, Xiang1, 2; Luo, Hui1; Xiao, Guangzong1, 3; Jones, Philip H.2 Source: Optics Letters, v 41, n 21, p 4935-4938, November 1, 2016
; ISSN: 01469592, E-ISSN: 15394794; DOI: 10.1364/OL.41.004935;
Publisher: OSA - The Optical SocietyAuthor affiliation: 1 College of Opto-Electric Science and Engineering, National University of Defense Technology, Changsha; 410073, China2 Department of Physics and Astronomy, University College London, Gower Street, London; WC1E 6BT, United Kingdom3 State Key Laboratory of Transient Optics and Photonics, Chinese Academy of Sciences, Xi'an; 710119, China
Abstract: In this Letter, we demonstrate the formation of a stable two-dimensional lattice of colloidal particles in the interference pattern formed by four evanescent optical fields at a dielectric interface. The microspheres are observed to form a two-dimensional square lattice with lattice vectors inclined relative to the beam propagation directions. We use digital video microscopy and particle tracking to measure the Brownian motion of particles bound in the lattice, and use this to characterize fluctuations in the local ordering of particles using the bond orientational order parameter, the probability distribution of which is shown to be a chi-squared distribution. An explanation for the form of this distribution is presented in terms of fluctuations of the modes of a ring of particles connected by springs. © 2016 Optical Society of America. (29 refs.)Main Heading: Optical latticesControlled terms: Brownian movement - Computer graphics - Evanescent fields - Multimedia systems - Probability distributionsUncontrolled terms: Bond orientational order parameters - Chi-squared distribution - Dielectric interface - Digital video microscopy - Interference patterns - Propagation direction - Two dimensional square lattice - Two-dimensional latticesClassification Code: 701 Electricity and MagnetismElectricity and Magnetism - 723.5 Computer ApplicationsComputer Applications - 744.8 Laser Beam InteractionsLaser Beam Interactions - 801.3 Colloid ChemistryColloid Chemistry - 922.1 Probability TheoryProbability Theory
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Simulation of the electron collection efficiency of a PMT based on the MCP coated with high secondary yield material
Chen, Lin1, 2, 4, 5; Tian, Jinshou1, 5; Zhao, Tianchi3; Liu, Chunliang4; Liu, Hulin1; Wei, Yonglin1; Sai, Xiaofeng1; Chen, Ping1, 2; Wang, Xing1; Lu, Yu1; Hui, Dandan1, 2 Source: Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, v 835, p 94-98, November 1, 2016
; ISSN: 01689002; DOI: 10.1016/j.nima.2016.08.034;
Publisher: ElsevierAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics (XIOPM), Chinese Academy of Sciences (CAS, Xi'an; 710119, China2 Graduate School of Chinese Academy of Sciences (CAS), Beijing; 100049, China3 Institute of High Energy Physics (IHEP) of CAS, Beijing; 100049, China4 Xi'an Jiaotong University, Xi'an; 710049, China5 Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan; 030006, China
Abstract: Owning to the serious loss of photoelectrons striking at the input electrode of traditional microchannel plate (MCP), photoelectron collection efficiency (CE) of photomultiplier tubes based on MCP (MCP-PMTs) fluctuates around the MCP open area fraction and cannot make a breakthrough. Depositing a thin film of high secondary electron yield material on the MCP is proposed as an effective approach to improve the CE. The available simulation and experimental data to validate it, however, is sparse. In our work, a three-dimensional small area MCP model is developed in CST Studio Suite to evaluate the collection efficiencies of PMTs based on the traditional MCP and the coated one, respectively. Results predict that CE of the PMT based on the coated MCP has a significant increase and a better uniformity, which is expected to reach 100%. © 2016 Elsevier B.V. (22 refs.)Main Heading: Image storage tubesControlled terms: Deposition - Efficiency - Electron emission - Microchannels - Photoelectrons - Photomultipliers - Photons - Secondary emissionUncontrolled terms: Area fraction - Collection efficiency - Effective approaches - Electron collections - Micro channel plate - Photo multiplier tube - Photoelectron collection efficiency - Secondary electron yieldClassification Code: 714.1 Electron TubesElectron Tubes - 802.3 Chemical OperationsChemical Operations - 913.1 Production EngineeringProduction Engineering - 931.3 Atomic and Molecular PhysicsAtomic and Molecular Physics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Multiple representations-based face sketch-photo synthesis
Peng, Chunlei1; Gao, Xinbo2; Wang, Nannan3; Tao, Dacheng4; Li, Xuelong5; Li, Jie1 Source: IEEE Transactions on Neural Networks and Learning Systems, v 27, n 11, p 2201-2215, November 2016
; ISSN: 2162237X, E-ISSN: 21622388; DOI: 10.1109/TNNLS.2015.2464681;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 School of Electronic Engineering, Xidian University, Xi'an; 710071, China2 State Key Laboratory of Integrated Services Networks, School of Electronic Engineering, Xidian University, Xi'an; 710071, China3 State Key Laboratory of Integrated Services Networks, School of Telecommunications Engineering, Xidian University, Xi'an; 710071, China4 Centre for Quantum Computation and Intelligent Systems, Faculty of Engineering and Information Technology, University of Technology, Sydney; NSW; 2007, Australia5 Center for OPTical IMagery Analysis and Learning (OPTIMAL), State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China
Abstract: Face sketch-photo synthesis plays an important role in law enforcement and digital entertainment. Most of the existing methods only use pixel intensities as the feature. Since face images can be described using features from multiple aspects, this paper presents a novel multiple representations-based face sketch-photo-synthesis method that adaptively combines multiple representations to represent an image patch. In particular, it combines multiple features from face images processed using multiple filters and deploys Markov networks to exploit the interacting relationships between the neighboring image patches. The proposed framework could be solved using an alternating optimization strategy and it normally converges in only five outer iterations in the experiments. Our experimental results on the Chinese University of Hong Kong (CUHK) face sketch database, celebrity photos, CUHK Face Sketch FERET Database, IIIT-D Viewed Sketch Database, and forensic sketches demonstrate the effectiveness of our method for face sketch-photo synthesis. In addition, cross-database and database-dependent style-synthesis evaluations demonstrate the generalizability of this novel method and suggest promising solutions for face identification in forensic science. © 2012 IEEE. (60 refs.)Main Heading: Image processingControlled terms: Database systems - Face recognition - Forensic scienceUncontrolled terms: Alternating optimizations - Chinese universities - Digital entertainment - Face identification - Face sketch-photo synthesis - Forensic sketches - Multiple representation - Synthesis evaluationClassification Code: 723.3 Database SystemsDatabase Systems
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Deep representation for abnormal event detection in crowded scenes
Feng, Yachuang1, 2; Yuan, Yuan1; Lu, Xiaoqiang1 Source: MM 2016 - Proceedings of the 2016 ACM Multimedia Conference, p 591-595, October 1, 2016, MM 2016 - Proceedings of the 2016 ACM Multimedia Conference; ISBN-13: 9781450336031; DOI: 10.1145/2964284.2967290; Conference: 24th ACM Multimedia Conference, MM 2016, October 15, 2016 - October 19, 2016; Sponsor: ACM SIGMM;
Publisher: Association for Computing Machinery, IncAuthor affiliation: 1 Center for OPTical IMagery Analysis and Learning (OPTIMAL), State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, Shaanxi; 710119, China2 University of Chinese Academy of Sciences, Beijing; 100049, China
Abstract: Abnormal event detection is extremely important, especially for video surveillance. Nowadays, many detectors have been proposed based on hand-crafted features. However, it remains challenging to effectively distinguish abnormal events from normal ones. This paper proposes a deep representation based algorithm which extracts features in an unsupervised fashion. Specially, appearance, texture, and short-term motion features are automatically learned and fused with stacked denoising autoencoders. Subsequently, long-term temporal clues are modeled with a long short-term memory (LSTM) recurrent network, in order to discover meaningful regularities of video events. The abnormal events are identified as samples which disobey these regularities. Moreover, this paper proposes a spatial anomaly detection strategy via manifold ranking, aiming at excluding false alarms. Experiments and comparisons on real world datasets show that the proposed algorithm outper-forms state of the arts for the abnormal event detection problem in crowded scenes. © 2016 ACM. (13 refs.)Main Heading: Security systemsControlled terms: Motion analysisUncontrolled terms: Abnormal event detections - Crowded scene - Deep representation - Long short term memory - Real-world datasets - Recurrent networks - Spatial anomalies - Video surveillanceClassification Code: 723.2 Data Processing and Image ProcessingData Processing and Image Processing - 914.1 Accidents and Accident PreventionAccidents and Accident Prevention
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Interference data correction methods for lunar observation with a large-aperture static imaging spectrometer
Zhang, Geng1; Wang, Shuang1; Li, Libo1; Hu, Xiuqing2; Hu, Bingliang1 Source: Applied Optics, v 55, n 31, p 8770-8778, November 1, 2016
; ISSN: 1559128X, E-ISSN: 21553165; DOI: 10.1364/AO.55.008770;
Publisher: OSA - The Optical SocietyAuthor affiliation: 1 Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; Shaanxi; 710119, China2 National Satellite Meteorological Center, China Meteorological Administration, Beijing; 100081, China
Abstract: The lunar spectrum has been used in radiometric calibration and sensor stability monitoring for spaceborne optical sensors. A ground-based large-aperture static image spectrometer (LASIS) can be used to acquire the lunar spectral image for lunar radiance model improvement when the moon orbits over its viewing field. The lunar orbiting behavior is not consistent with the desired scanning speed and direction of LASIS. To correctly extract interferograms from the obtained data, a translation correction method based on image correlation is proposed. This method registers the frames to a reference frame to reduce accumulative errors. Furthermore, we propose a circle-matching-based approach to achieve even higher accuracy during observation of the full moon. To demonstrate the effectiveness of our approaches, experiments are run on true lunar observation data. The results show that the proposed approaches outperform the state-of-the-art methods. © 2016 Optical Society of America. (14 refs.)Main Heading: MoonControlled terms: Orbits - Spectrometers - SpectroscopyUncontrolled terms: Accumulative errors - Correction method - Image correlations - Interference data - Lunar observations - Radiometric calibrations - Stability monitoring - State-of-the-art methodsClassification Code: 657.2 Extraterrestrial Physics and Stellar PhenomenaExtraterrestrial Physics and Stellar Phenomena - 741.3 Optical Devices and SystemsOptical Devices and Systems
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Influence of electrode types on the electrohydrodynamic instability patterning process: a comparative study
Liu, Minzhe1, 2; Li, Hefu1; Yu, Weixing3; Wang, Taisheng1; Liu, Zhenyu1; Desmulliez, Marc. P. Y.4 Source: RSC Advances, v 6, n 113, p 112300-112306, 2016; E-ISSN: 20462069; DOI: 10.1039/C6RA05596F;
Publisher: Royal Society of ChemistryAuthor affiliation: 1 State Key Laboratory of Applied Optics, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, No. 3888, Dongnanhu Road, Changchun; Jilin, China2 University of the Chinese Academy of Science, Beijing; 100049, China3 Key Laboratory of Spectral Imaging Technology, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, No. 17, Xinxi Road, Xian; 710119, China4 MIcroSystems Engineering Centre (MISEC), School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh; EH14 4AS, United Kingdom
Abstract: This article studies the effect that different types of patterned electrodes have on the electrohydrodynamic instability patterning (EHDIP) process for the faithful replication of micro- and nanostructures. Two types of patterned electrodes are studied. One is fully conductive, i.e. both pattern and substrate are conductive. The other type has conductive microstructures fabricated on a dielectric substrate. By employing the COMSOL™ Multiphysics software package, a rigorous numerical simulation of the EHDIP process has been carried out for both types of electrodes. The simulation results show that both electrodes can realize a faithful replication of the micro- and nanostructures once the variable, ΔE/Δx, reaches the critical value. Moreover, it is demonstrated that a fully conductive template is preferred if a small polymer film thickness is employed; a partially conductive electrode is preferred for larger film thickness. These results provide guidelines for the better control of the EHDIP process in order to realize the perfect pattern replication of structures for a variety of applications in MEMS or micro/nanofluidics. © The Royal Society of Chemistry. (38 refs.)Main Heading: NanostructuresControlled terms: Computer software - Dielectric materials - Electrodes - Electrohydrodynamics - Film thickness - Polymer films - Semiconducting filmsUncontrolled terms: Comparative studies - Conductive electrodes - Conductive microstructures - Dielectric substrates - Electrohydrodynamic instability - Micro and nanostructures - Multiphysics software - Patterned electrodeClassification Code: 708.1 Dielectric MaterialsDielectric Materials - 712.1 Semiconducting MaterialsSemiconducting Materials - 723 Computer Software, Data Handling and ApplicationsComputer Software, Data Handling and Applications - 761 NanotechnologyNanotechnology - 815.1 Polymeric MaterialsPolymeric Materials - 933 Solid State PhysicsSolid State Physics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Misalignment induced aberration off-axis optical system
Pang, Zhihai1; Fan, Xuewu1; Ma, Zhen1; Zou, Gangyi1 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 9682, 2016, 8th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Large Mirrors and Telescopes
; ISSN: 0277786X, E-ISSN: 1996756X; ISBN-13: 9781628419177; DOI: 10.1117/12.2243446; Article number: 96820U; Conference: 8th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Large Mirrors and Telescopes, AOMATT 2016, April 26, 2016 - April 29, 2016; Sponsor: Chinese Academy of Sciences, Institute of Optics and Electronics (IOE); The Chinese Optical Society (COS);
Publisher: SPIEAuthor affiliation: 1 Space Optics Laboratory, Xi'An Institute of Optics and Precision Mechanics. CAS, Shanxi Xi'an; 710119, China
Abstract: Through introducing transformed pupil vector and shifted center of aberration fields vector into the nodal aberration expansions of an axially symmetric optical system, the aberration expression in third order of an off-axis optical system and misaligned off-axis optical system are detailed. Nodal aberration characteristics of misaligned off-axis optical system are revealed only by analyzing the pupil decentration vector, aberration fields shifted vector and the aberration coefficients of the axially symmetric optical system. Actually, it is well demonstrated that the 3rd spherical aberration, 3rd coma, 3rd astigmatism in a misalignment off-axis system are comparable to the aberrations in a misalignment axially symmetric system. Otherwise it will not only induced constant 3rd spherical aberration but also constant 3rd coma and 3rd astigmatism over the field of view, when aligned an off-axis optical system elements with error axial spacing. © 2016 SPIE. (9 refs.)Main Heading: Optical systemsControlled terms: Aberrations - Alignment - Aspherics - Manufacture - Mirrors - Optical testing - Telescopes - VectorsUncontrolled terms: Aberration coefficients - Axial spacing - Axially symmetric - Decentration - Field of views - Off-axis - Spherical aberrations - System elementsClassification Code: 537.1 Heat Treatment ProcessesHeat Treatment Processes - 601.1 Mechanical DevicesMechanical Devices - 741.1 Light/OpticsLight/Optics - 741.3 Optical Devices and SystemsOptical Devices and Systems - 921.1 AlgebraAlgebra
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Design and research of moving objects dimension measurement system based on linear array CCD
Lei, Fanpu1, 2, 3; Bai, Yonglin3; Zhu, Bingli3 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 10154, 2016, Advanced Optical Design and Manufacturing Technology and Astronomical Telescopes and Instrumentation
; ISSN: 0277786X, E-ISSN: 1996756X; DOI: 10.1117/12.2246493; Article number: 101540R; Conference: International Symposium on Advanced Optical Design and Manufacturing Technologies and International Symposium on Astronomical Telescope and Instrumentation, May 9, 2016 - May 11, 2016; Sponsor: China High-Tech Industrialization Association (CHIA); Chinese Society for Optical Engineering (CSOE);
Publisher: SPIEAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, CAS, Xi'an; 710119, China2 University of Chinese Academy of Sciences, Beijing; 100049, China3 Key Laboratory of Ultrafast Diagnostic Technique, Xi'an Institute of Optics and Precision Mechanics of Chinese Academy of Sciences, Xi'an; 710119, China
Abstract: A novel moving objects dimension measurement system based on the linear array CCD is designed. The light source is a pulsed laser with pulse width 200ns. Single point of light passes through lens converted to parallel light which will illuminate to the CCD through the moving object to be tested. CCD pixels which are blocked by the object while light is on are low, and the remaining pixels are high conversely. The distance of the tested objects while light is on can be ignored since the light pulse width is much smaller than the integration time of CCD (generally). The size of the tested object can be achieved by the number of dark pixels of CCD while light is on. This paper introduces the principle and composition of the dimension measurement system. The results show that this system can measure the size of moving objects and measuring accuracy is better than 50 microns. Accuracy and stability of the system can achieve actual production requirements when the object's moving speed is smaller than 50mm/s. Optimizing the parallelism of the parallel light, the measurement accuracy can be further improved. © 2016 SPIE. (7 refs.)Main Heading: LightControlled terms: Inclusions - Light sources - Manufacture - Optical design - Optical variables measurement - Pixels - Pulsed lasers - Radio telescopes - System stability - TelescopesUncontrolled terms: Dimension measurements - Integration time - Linear array CCD - Measurement accuracy - Measuring accuracy - Moving objects - Parallel light - Production requirementsClassification Code: 537.1 Heat Treatment ProcessesHeat Treatment Processes - 657.2 Extraterrestrial Physics and Stellar PhenomenaExtraterrestrial Physics and Stellar Phenomena - 741.1 Light/OpticsLight/Optics - 744.1 Lasers, GeneralLasers, General - 941.4 Optical Variables MeasurementsOptical Variables Measurements - 951 Materials ScienceMaterials Science - 961 Systems ScienceSystems Science
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Radiometric calibration of space remote sensing camera
Guo, Huinan1; Yang, Hongtao1; Song, Xiaodong1; Zhao, Ronghui1; Ma, Nan2; Wang, Wei3 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 10033, 2016, Eighth International Conference on Digital Image Processing, ICDIP 2016
; ISSN: 0277786X, E-ISSN: 1996756X; ISBN-13: 9781510605039; DOI: 10.1117/12.2245147; Article number: 100333I; Conference: 8th International Conference on Digital Image Processing, ICDIP 2016, May 20, 2016 - May 23, 2016; Sponsor: Chengdu University of Information Technology; Chinese Academy of Sciences Chengdu Institute of Computer Applications; International Association of Computer Science and Information Technology; Sichuan Province Computer Federation;
Publisher: SPIEAuthor affiliation: 1 Xi'An Institute of Optics and Precision Mechanics of CAS, No.17, Xinxi Rd, Xi'an, Shaanxi, China2 People's Liberation Army of No.95879, Chengdu, Sichuan, China3 Xianyang Vocational Technical College, No.1 Tongyi Rd, Xianyang, Shaanxi, China
Abstract: Radiometric calibration is an important part for space remote sensing camera to obtain an accurate radiation value of ground target. The main significance of radiometric calibration is to reduce the influence by external scene and internal parameters of camera and to recover the real radiation property of objects. In order to break the limitation of line array imaging sensor, we propose a radiometric calibration method based on camera state matrix for area array camera. According to camera response characteristics, calculate and fit a functional relationship between the input radiance energy and the output digital number. Meanwhile, analyse and describe the procedure of radiometric calibration in detail. Experimental results indicates that the calibration method can provide high accuracy linear fitting parameters and can be widely applied to a large variety digital imaging systems. © 2016 SPIE. (11 refs.)Main Heading: CalibrationControlled terms: Cameras - Image processing - Imaging systems - Radiometry - Remote sensing - Space opticsUncontrolled terms: Calibration method - Camera response - Digital imaging system - Functional relationship - Internal parameters - Radiation properties - Radiometric calibrations - Space remote sensing cameraClassification Code: 656.1 Space FlightSpace Flight - 742.2 Photographic EquipmentPhotographic Equipment - 746 Imaging TechniquesImaging Techniques - 944.8 Radiation MeasurementsRadiation Measurements
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Preface
Hauptmann, Alex1; Gao, Xinbo2; Li, Xuelong3; Ji, Rongrong4; Deng, Cheng2; Gao, Yue5 Source: ACM International Conference Proceeding Series, v 19-21-August-2016, August 19, 2016, Proceedings of the International Conference on Internet Multimedia Computing and Service, ICIMCS 2016; ISBN-13: 9781450348508; Conference: 8th International Conference on Internet Multimedia Computing and Service, ICIMCS 2016, August 19, 2016 - August 21, 2016; Sponsor: Xidian University;
Publisher: Association for Computing MachineryAuthor affiliation: 1 Carnegie Mellon University, United States2 Xidian University, China3 Xi'an Institute of Optics and Precision Mechanics, CAS, China4 Xiamen University, China5 Tsinghua University, China
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


126 W fiber laser at 1018 nm and its application in tandem pumped fiber amplifier
Yang, Hening1, 2, 3; Zhao, Wei1; Si, Jinhai2; Zhao, Baoyin1; Zhu, Yonggang1 Source: Journal of Optics (United Kingdom), v 18, n 12, December 2016
; ISSN: 20408978, E-ISSN: 20408986; DOI: 10.1088/2040-8978/18/12/125801; Article number: 125801;
Publisher: Institute of Physics PublishingAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Science, Xi'an; 710119, China2 School of Electronics and Information Engineering, Xi'An Jiaotong University, Xi'an; 710049, China3 University of Chinese Academy of Sciences, Beijing; 100049, China
Abstract: We report on a 126 W fiber laser operating at 1018 nm with an optical efficiency of 75%. The optimal length for such a fiber laser is theoretically analyzed using steady-state rate equations including amplified spontaneous emission. Excellent agreement on the maximum output power is achieved between the numerical result and the experimental counterpart. Furthermore, a monolithic tandem pumped fiber amplifier is established by using conventional 30/250 μm double clad ytterbium-doped fiber, and 185 W output power with 85% optical efficiency is realized. © 2016 IOP Publishing Ltd. (21 refs.)Main Heading: Fiber amplifiersControlled terms: Efficiency - Equations of state - Fiber lasers - Fibers - Pumping (laser)Uncontrolled terms: Amplified spontaneous emissions - Fiber laser and amplifiers - ITS applications - Maximum output power - Numerical results - Optical efficiency - Steady state rates - Ytterbium doped fibersClassification Code: 744.1 Lasers, GeneralLasers, General - 744.4 Solid State LasersSolid State Lasers - 913.1 Production EngineeringProduction Engineering
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Online fabrication scheme of helical long-period fiber grating for liquid-level sensing
Ren, Kaili1, 2, 3; Ren, Liyong1; Liang, Jian1, 3; Kong, Xudong1, 3; Ju, Haijuan1; Xu, Yiping1, 3; Wu, Zhaoxin2 Source: Applied Optics, v 55, n 34, p 9675-9679, December 1, 2016
; ISSN: 1559128X, E-ISSN: 21553165; DOI: 10.1364/AO.55.009675;
Publisher: OSA - The Optical SocietyAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China2 Key Laboratory of Photonics Technology for Information, Department of Electronics Science and Technology, School of Electronic and Information Engineering, Xi'an Jiaotong University, Xi'an; 710049, China3 University of Chinese Academy of Sciences, Beijing; 100049, China
Abstract: We present a novel online fabrication scheme of helical long-period fiber gratings (H-LPFGs) by directly twisting a standard single-mode fiber (SMF) in a microheater. This is done by taking advantage of the inherent core-cladding eccentricity in SMF. We adopt a fiber optic rotary joint to eliminate the accompanying twisting spiral for real-time spectral monitoring and a stepping mechanical system to accurately control the twisting length in fabrication. As a consequence, low-cost and high-quality H-LPFGs can be readily fabricated. Meanwhile, by using this kind of H-LPFG, we design a simple and low-cost wavelength-interrogated liquid-level sensor with a high sensitivity of 0.1 nm/mm. © 2016 Optical Society of America. (28 refs.)Main Heading: Diffraction gratingsControlled terms: Fabrication - Fibers - Single mode fibersUncontrolled terms: Fiber optic rotary joints - High quality - High sensitivity - Liquid level - Liquid level sensors - Long period fiber grating - Mechanical systems - Standard single mode fibersClassification Code: 741.1.2 Fiber OpticsFiber Optics - 741.3 Optical Devices and SystemsOptical Devices and Systems
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Unsupervised feature selection with structured graph optimization
Nie, Feiping1; Zhu, Wei1; Li, Xuelong2 Source: 30th AAAI Conference on Artificial Intelligence, AAAI 2016, p 1302-1308, 2016, 30th AAAI Conference on Artificial Intelligence, AAAI 2016; ISBN-13: 9781577357605; Conference: 30th AAAI Conference on Artificial Intelligence, AAAI 2016, February 12, 2016 - February 17, 2016; Sponsor: Artificial Intelligence; Baidu; et al.; IBM; Infosys; NSF;
Publisher: AAAI pressAuthor affiliation: 1 Center for OPTical IMagery Analysis and Learning (OPTIMAL), School of Computer Science, Northwestern Polytechnical University, Xi'an, Shaanxi; 710072, China2 Center for OPTical IMagery Analysis and Learning (OPTIMAL), Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, Shaanxi; 710119, China
Abstract: Since amounts of unlabelled and high-dimensional data needed to be processed, unsupervised feature selection has become an important and challenging problem in machine learning. Conventional embedded unsupervised methods always need to construct the similarity matrix, which makes the selected features highly depend on the learned structure. However real world data always contain lots of noise samples and features that make the similarity matrix obtained by original data can't be fully relied. We propose an unsupervised feature selection approach which performs feature selection and local structure learning simultaneously, the similarity matrix thus can be determined adaptively. Moreover, we constrain the similarity matrix to make it contain more accurate information of data structure, thus the proposed approach can select more valuable features. An efficient and simple algorithm is derived to optimize the problem. Experiments on various benchmark data sets, including handwritten digit data, face image data and biomedical data, validate the effectiveness of the proposed approach. © 2016, Association for the Advancement of Artificial Intelligence (www.aaai.org). All rights reserved. (26 refs.)Main Heading: Feature extractionControlled terms: Artificial intelligence - Clustering algorithms - Human computer interaction - Learning systems - Matrix algebraUncontrolled terms: Handwritten digit - High dimensional data - Local structure - Similarity matrix - SIMPLE algorithm - Structured graphs - Unsupervised feature selection - Unsupervised methodClassification Code: 723.4 Artificial IntelligenceArtificial Intelligence - 903.1 Information Sources and AnalysisInformation Sources and Analysis - 921.1 AlgebraAlgebra
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Method used to test the imaging consistency of binocular camera's left-right optical system
Liu, Meiying1; Wang, Hu1; Liu, Jie1; Xue, Yaoke1; Yang, Shaodong1; Zhao, Hui1 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 9684, 2016, 8th International Symposium on Advanced Optical Manufacturing and Testing Technology: Optical Test, Measurement Technology, and Equipment
; ISSN: 0277786X, E-ISSN: 1996756X; ISBN-13: 9781628419191; DOI: 10.1117/12.2242265; Article number: 96842R; Conference: 8th International Symposium on Advanced Optical Manufacturing and Testing Technology: Optical Test, Measurement Technology, and Equipment, AOMATT 2016, April 26, 2016 - April 29, 2016; Sponsor: Chinese Academy of Sciences, Institute of Optics and Electronics (IOE); The Chinese Optical Society (COS);
Publisher: SPIEAuthor affiliation: 1 Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Science, No. 17 Xinxi Road, Xi'an; 710119, China
Abstract: To binocular camera, the consistency of optical parameters of the left and the right optical system is an important factor that will influence the overall imaging consistency. In conventional testing procedure of optical system, there lacks specifications suitable for evaluating imaging consistency. In this paper, considering the special requirements of binocular optical imaging system, a method used to measure the imaging consistency of binocular camera is presented. Based on this method, a measurement system which is composed of an integrating sphere, a rotary table and a CMOS camera has been established. First, let the left and the right optical system capture images in normal exposure time under the same condition. Second, a contour image is obtained based on the multiple threshold segmentation result and the boundary is determined using the slope of contour lines near the pseudo-contour line. Third, the constraint of gray level based on the corresponding coordinates of left-right images is established and the imaging consistency could be evaluated through standard deviation σ of the imaging grayscale difference D (x, y) between the left and right optical system. The experiments demonstrate that the method is suitable for carrying out the imaging consistency testing for binocular camera. When the standard deviation 3σ distribution of imaging gray difference D (x, y) between the left and right optical system of the binocular camera does not exceed 5%, it is believed that the design requirements have been achieved. This method could be used effectively and paves the way for the imaging consistency testing of the binocular camera. © 2016 SPIE. (9 refs.)Main Heading: Optical systemsControlled terms: Binoculars - Bins - Cameras - Contour measurement - Image segmentation - Manufacture - Optical testing - StatisticsUncontrolled terms: Binocular camera - Contour line - Conventional testing - Integrating spheres - Measurement system - Multiple threshold - Optical imaging system - Standard deviationClassification Code: 537.1 Heat Treatment ProcessesHeat Treatment Processes - 694.4 StorageStorage - 741.3 Optical Devices and SystemsOptical Devices and Systems - 742.2 Photographic EquipmentPhotographic Equipment - 922.2 Mathematical StatisticsMathematical Statistics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Design of infrared signal processing system based on ZYNQ platform
Bai, Zhuoyu1, 2; Leng, Haibing1; Hu, Bingliang1; Wang, Shuang1 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 10157, 2016, Infrared Technology and Applications, and Robot Sensing and Advanced Control
; ISSN: 0277786X, E-ISSN: 1996756X; ISBN-13: 9781510607729; DOI: 10.1117/12.2246949; Article number: 101572N; Conference: International Symposium on Infrared Technology and Application and the International Symposiums on Robot Sensing and Advanced Control, May 9, 2016 - May 11, 2016; Sponsor: China High-Tech Industrialization Association (CHIA); Chinese Society for Optical Engineering (CSOE);
Publisher: SPIEAuthor affiliation: 1 XI'AN Institute of Optics and Precision Mechanics of CAS, China2 University of Chinese, Academy of Sciences, Beijing; 100049, China
Abstract: A newly developed real-time infrared signal processing system based on the heterogeneous multi-processor system on chip (MPSoC) is proposed in this paper. The architecture, hardware configuration, image pre-processing algorithms used in the system and the experimental result are presented. Compared to the infrared signal processing system in being, Xilinx Zynq-7000 All Programmable SoC has been used in the proposed system which is more portable, integrated, and has excellent performance during its signal processing. © 2016 SPIE. (8 refs.)Main Heading: Signal processingControlled terms: Infrared radiation - Integrated circuit design - Programmable logic controllers - System-on-chipUncontrolled terms: Hardware configurations - Image preprocessing - Infrared signal - Multi processor system on chips - Real time - ZYNQClassification Code: 714.2 Semiconductor Devices and Integrated CircuitsSemiconductor Devices and Integrated Circuits - 716.1 Information Theory and Signal ProcessingInformation Theory and Signal Processing - 732.1 Control EquipmentControl Equipment - 741.1 Light/OpticsLight/Optics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Generation of multi-photon entangled states with integrated optical frequency comb sources
Reimer, Christian1; Kues, Michael1; Roztocki, Piotr1; Caspani, Lucia1, 2; Bromberg, Yaron3; Wetzel, Benjamin1, 4; Little, Brent E.5; Chu, Sai T.6; Moss, David J.7; Morandotti, Roberto1 Source: Optics InfoBase Conference Papers, July 21, 2014, Frontiers in Optics, FiO 2016; ISBN-13: 9781943580194; DOI: 10.1364/FIO.2016.FW3F.2; Conference: Frontiers in Optics, FiO 2016, October 17, 2016 - October 21, 2016; Sponsor: APS-American Physical Society; OSA-The Optical Society;
Publisher: OSA - The Optical SocietyAuthor affiliation: 1 INRS-EMT, 1650 Boulevard Lionel-Boulet, Varennes; QC; J3X 1S2, Canada2 School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh; EH14 4AS, United Kingdom3 Department of Applied Physics, Yale University, New Haven; CT; 06520, United States4 Department of Physics and Astronomy, University of Sussex, Falmer, Brighton; BN1 9QH, United Kingdom5 Xi'an Institute of Optics and Precision Mechanics of CAS, Xi'an, China6 Department of Physics and Material Science, City University of Hong Kong, Tat Chee Avenue, Hong Kong7 Centre for Micro Photonics, Swinburne University of Technology, Hawthorne; VIC; 3122, Australia
Abstract: We demonstrate that four-photon entangled qubit states can be generated from an optical frequency combs source. This state generation is evidenced by four-photon quantum interference, and quantum state tomography reveals a fidelity above 64%. © OSA 2016. (13 refs.)Main Heading: Quantum theoryControlled terms: Natural frequencies - Optical materials - Photons - Quantum entanglementUncontrolled terms: Multi-photon entangled state - Optical frequency comb sources - Optical frequency combs - Quantum interference - Quantum state tomography - Qubit state - State generationsClassification Code: 741.3 Optical Devices and SystemsOptical Devices and Systems - 931.3 Atomic and Molecular PhysicsAtomic and Molecular Physics - 931.4 Quantum Theory; Quantum MechanicsQuantum Theory; Quantum Mechanics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


High-energy Q-switched Yb-doped fiber laser based on WS2film saturable absorber
Wang, Junli1; Li, Sha1; Wang, Yonggang3; Zhu, Jiangfeng1; Wei, Zhiyi2 Source: Optics InfoBase Conference Papers, July 21, 2014, Asia Communications and Photonics Conference, ACPC 2016; ISBN-13: 9780960038008; DOI: 10.1364/ACPC.2016.AF4I.1; Conference: Asia Communications and Photonics Conference, ACPC 2016, November 2, 2016 - November 5, 2016; Sponsor: CHINA INSTITUTE OF COMMUNICATIONS; IEEE Photonics society; OSA-The Optical Society; SPIE; The CHINESE OPTICAL SOCITETY;
Publisher: OSA - The Optical SocietyAuthor affiliation: 1 School of Physics and Optoelectronic Engineering, Xidian University, Xi'an; 710071, China2 Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing; 100190, China3 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of sciences, Xi'an; 710119, China
Abstract: An all-fiber high-energy Q-switched Yb-doped fiber laser using WS2film as the saturable absorber (SA) is demonstrated. The highest single pulse energy of 56.50 nJ and the shortest pulse width of 1.0 μs were achieved. © OSA 2016. (11 refs.)Main Heading: Saturable absorbersControlled terms: Fiber lasers - Photonics - Q switching - YtterbiumUncontrolled terms: All fiber - Pulsewidths - Q-switched - Single pulse energy - Yb doped fiber laserClassification Code: 547.2 Rare Earth MetalsRare Earth Metals - 741.1 Light/OpticsLight/Optics - 744 LasersLasers
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Improved artificial bee colony algorithm with randomized Halton sequence
He, Zhen-An1; Ma, Caiwen1 Source: 2016 2nd IEEE International Conference on Computer and Communications, ICCC 2016 - Proceedings, p 1270-1273, May 10, 2017, 2016 2nd IEEE International Conference on Computer and Communications, ICCC 2016 - Proceedings; ISBN-13: 9781467390262; DOI: 10.1109/CompComm.2016.7924908; Article number: 7924908; Conference: 2nd IEEE International Conference on Computer and Communications, ICCC 2016, October 14, 2016 - October 17, 2016;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, China
Abstract: The artificial bee colony (ABC) algorithm has gained popularity for solutions to many real-world complex problems because of its simplicity and efficiency. However, it is good at exploration but poor at exploitation and early gets trapped into local optimum in some case, which prevents the artificial bee colony algorithm from finding the final result accuracy and efficiently for complex problems. It's known to all that population initialization is an important factor affecting convergence performance of ABC. In this paper, a modified artificial bee colony algorithm with randomized Halton sequence was proposed. A series of experiments were performed on benchmark functions to testify the superiority of our proposed algorithm, and results were compared with other initialization algorithms including opposition-based learning, random initialization and chaotic initialization. The results indicate that our proposed algorithm provides higher solution accuracy and faster convergence speed. © 2016 IEEE. (20 refs.)Main Heading: Evolutionary algorithmsControlled terms: OptimizationUncontrolled terms: Artificial bee colony algorithms - Artificial bee colony algorithms (ABC) - Benchmark functions - Convergence performance - Faster convergence - Halton sequences - Opposition-based learning - Population initializationsClassification Code: 921.5 Optimization TechniquesOptimization Techniques
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Pedestrian detection inspired by appearance constancy and shape symmetry
Cao, Jiale1; Pang, Yanwei1; Li, Xuelong2 Source: Proceedings of the IEEE Computer Society Conference on Computer Vision and Pattern Recognition, v 2016-December, p 1316-1324, December 9, 2016, Proceedings - 29th IEEE Conference on Computer Vision and Pattern Recognition, CVPR 2016
; ISSN: 10636919; ISBN-13: 9781467388504; DOI: 10.1109/CVPR.2016.147; Article number: 7780516; Conference: 29th IEEE Conference on Computer Vision and Pattern Recognition, CVPR 2016, June 26, 2016 - July 1, 2016;
Publisher: IEEE Computer SocietyAuthor affiliation: 1 School of Electronic Information Engineering, Tianjin University, China2 Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, China
Abstract: The discrimination and simplicity of features are very important for effective and efficient pedestrian detection. However, most state-of-the-art methods are unable to achieve good tradeoff between accuracy and efficiency. Inspired by some simple inherent attributes of pedestrians (i.e., appearance constancy and shape symmetry), we propose two new types of non-neighboring features (NNF): side-inner difference features (SIDF) and symmetrical similarity features (SSF). SIDF can characterize the difference between the background and pedestrian and the difference between the pedestrian contour and its inner part. SSF can capture the symmetrical similarity of pedestrian shape. However, it's difficult for neighboring features to have such above characterization abilities. Finally, we propose to combine both non-neighboring and neighboring features for pedestrian detection. It's found that nonneighboring features can further decrease the average miss rate by 4.44%. Experimental results on INRIA and Caltech pedestrian datasets demonstrate the effectiveness and efficiency of the proposed method. Compared to the state-of the-art methods without using CNN, our method achieves the best detection performance on Caltech, outperforming the second best method (i.e., Checkerboards) by 1.63%. © 2016 IEEE. (37 refs.)Main Heading: Feature extractionControlled terms: Computer vision - Efficiency - Object detection - Pattern recognitionUncontrolled terms: Caltech - Detection performance - Effectiveness and efficiencies - Miss-rate - Pedestrian detection - Shape symmetry - State-of-the-art methodsClassification Code: 723.2 Data Processing and Image ProcessingData Processing and Image Processing - 723.5 Computer ApplicationsComputer Applications - 913.1 Production EngineeringProduction Engineering
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Low-Rank Preserving Projections
Lu, Yuwu1, 2; Lai, Zhihui3, 4; Xu, Yong2; Li, Xuelong5; Zhang, David6; Yuan, Chun1 Source: IEEE Transactions on Cybernetics, v 46, n 8, p 1900-1913, August 2016
; ISSN: 21682267; DOI: 10.1109/TCYB.2015.2457611; Article number: 7182766;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 Tsinghua-CUHK Joint Research Center for Media Sciences, Technologies and Systems, Graduate School at Shenzhen, Tsinghua University, Shenzhen; 518055, China2 Bio-Computing Research Center, Shenzhen Graduate School, Harbin Institute of Technology, Shenzhen; 518055, China3 College of Computer Science and Software Engineering, Shenzhen University, Shenzhen; 518055, China4 Institute of Textiles and Clothing, Hong Kong Polytechnic University, Hong Kong5 Center for OPTical IMagery Analysis and Learning, State Key Laboratory of Transient Optics and Photonics, Chinese Academy of Sciences, Xi'an; 710119, China6 Biometrics Research Center, Hong Kong Polytechnic University, Hong Kong
Abstract: As one of the most popular dimensionality reduction techniques, locality preserving projections (LPP) has been widely used in computer vision and pattern recognition. However, in practical applications, data is always corrupted by noises. For the corrupted data, samples from the same class may not be distributed in the nearest area, thus LPP may lose its effectiveness. In this paper, it is assumed that data is grossly corrupted and the noise matrix is sparse. Based on these assumptions, we propose a novel dimensionality reduction method, named low-rank preserving projections (LRPP) for image classification. LRPP learns a low-rank weight matrix by projecting the data on a low-dimensional subspace. We use the L21norm as a sparse constraint on the noise matrix and the nuclear norm as a low-rank constraint on the weight matrix. LRPP keeps the global structure of the data during the dimensionality reduction procedure and the learned low rank weight matrix can reduce the disturbance of noises in the data. LRPP can learn a robust subspace from the corrupted data. To verify the performance of LRPP in image dimensionality reduction and classification, we compare LRPP with the state-of-the-art dimensionality reduction methods. The experimental results show the effectiveness and the feasibility of the proposed method with encouraging results. © 2015 IEEE. (51 refs.)Main Heading: Image classificationControlled terms: Computer vision - Data reduction - Face recognition - Matrix algebra - Pattern recognitionUncontrolled terms: Dimensionality reduction - Dimensionality reduction method - Dimensionality reduction techniques - Global structure - Locality preserving projections - Low-dimensional subspace - Rank constraints - State of the art
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Robust Semi-Supervised Subspace Clustering via Non-Negative Low-Rank Representation
Fang, Xiaozhao1; Xu, Yong1, 2; Li, Xuelong3; Lai, Zhihui1; Wong, Wai Keung4, 5 Source: IEEE Transactions on Cybernetics, v 46, n 8, p 1828-1838, August 2016
; ISSN: 21682267; DOI: 10.1109/TCYB.2015.2454521; Article number: 7175026;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 Bio-Computing Research Center, Shenzhen Graduate School, Harbin Institute of Technology, Shenzhen, Guangdong; 518055, China2 Key Laboratory of Network Oriented Intelligent Computation, Shenzhen, Guangdong; 518055, China3 Center for OPTical IMagery Analysis and Learning, State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, Shaanxi; 710119, China4 Institute of Textiles and Clothing, Hong Kong Polytechnic University, Hong Kong5 Hong Kong Polytechnic University, Shenzhen Research Institute, Shenzhen; 518055, China
Abstract: Low-rank representation (LRR) has been successfully applied in exploring the subspace structures of data. However, in previous LRR-based semi-supervised subspace clustering methods, the label information is not used to guide the affinity matrix construction so that the affinity matrix cannot deliver strong discriminant information. Moreover, these methods cannot guarantee an overall optimum since the affinity matrix construction and subspace clustering are often independent steps. In this paper, we propose a robust semi-supervised subspace clustering method based on non-negative LRR (NNLRR) to address these problems. By combining the LRR framework and the Gaussian fields and harmonic functions method in a single optimization problem, the supervision information is explicitly incorporated to guide the affinity matrix construction and the affinity matrix construction and subspace clustering are accomplished in one step to guarantee the overall optimum. The affinity matrix is obtained by seeking a non-negative low-rank matrix that represents each sample as a linear combination of others. We also explicitly impose the sparse constraint on the affinity matrix such that the affinity matrix obtained by NNLRR is non-negative low-rank and sparse. We introduce an efficient linearized alternating direction method with adaptive penalty to solve the corresponding optimization problem. Extensive experimental results demonstrate that NNLRR is effective in semi-supervised subspace clustering and robust to different types of noise than other state-of-the-art methods. © 2015 IEEE. (41 refs.)Main Heading: Matrix algebraControlled terms: Cluster analysis - Clustering algorithms - Harmonic functions - OptimizationUncontrolled terms: Alternating direction methods - Discriminant informations - Label information - Linear combinations - Low-rank representations - Optimization problems - State-of-the-art methods - Sub-Space Clustering
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Dual-clustering-based hyperspectral band selection by contextual analysis
Yuan, Yuan1; Lin, Jianzhe1; Wang, Qi2 Source: IEEE Transactions on Geoscience and Remote Sensing, v 54, n 3, p 1431-1445, March 1, 2016
; ISSN: 01962892; DOI: 10.1109/TGRS.2015.2480866; Article number: 7295589;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 Center for OPTical IMagery Analysis and Learning (OPTIMAL), State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, China2 School of Computer Science and the Center, OPTical IMagery Analysis and Learning (OPTIMAL), Northwestern Polytechnical University, Xi'an, China
Abstract: Hyperspectral image (HSI) involves vast quantities of information that can help with the image analysis. However, this information has sometimes been proved to be redundant, considering specific applications such as HSI classification and anomaly detection. To address this problem, hyperspectral band selection is viewed as an effective dimensionality reduction method that can remove the redundant components of HSI. Various HSI band selection methods have been proposed recently, and the clustering-based method is a traditional one. This agglomerative method has been considered simple and straightforward, while the performance is generally inferior to the state of the art. To tackle the inherent drawbacks of the clustering-based band selection method, a new framework concerning on dual clustering is proposed in this paper. The main contribution can be concluded as follows: 1) a novel descriptor that reveals the context of HSI efficiently; 2) a dual clustering method that includes the contextual information in the clustering process; 3) a new strategy that selects the cluster representatives jointly considering the mutual effects of each cluster. Experimental results on three real-world HSIs verify the noticeable accuracy of the proposed method, with regard to the HSI classification application. The main comparison has been conducted among several recent clustering-based band selection methods and constraint-based band selection methods, demonstrating the superiority of the technique that we present. © 1980-2012 IEEE. (51 refs.)Main Heading: Classification (of information)Controlled terms: Cluster analysis - Clustering algorithms - SpectroscopyUncontrolled terms: Agglomerative methods - Anomaly detection - Clustering process - Contextual analysis - Contextual information - Dimensionality reduction method - Hyperspectral images - State of the art
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Effective transfer of micron-size graphene to microfibers for photonic applications
Wu, Xiaoqin1; Yu, Shaoliang1; Yang, Huiran2; Li, Wenlei2; Liu, Xueming2; Tong, Limin1 Source: Carbon, v 96, p 1114-1119, January 2016
; ISSN: 00086223; DOI: 10.1016/j.carbon.2015.10.069;
Publisher: Elsevier LtdAuthor affiliation: 1 State Key Laboratory of Modern Optical Instrumentation, Department of Optical Engineering, Zhejiang University, Hangzhou, China2 State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, China
Abstract: We demonstrate an effective approach to transferring micron-size CVD graphene layers onto freestanding microfibers. With micro-manipulation, the coating position and length of the graphene films can be precisely controlled. By coating micrometer-scale (e.g., 20 μm) graphene films onto microfibers with diameters down to 1 μm, we can achieve significantly enhanced light-graphene interaction (e.g., a low saturable-absorption threshold of 40 MW/cm2) and simultaneously maintain a high transmission (73% in maximum) as well. In addition, we use these microscale CVD graphene-coated microfibers (GCMs) as saturable absorbers for all-optical modulation at 1550-nm wavelength with a modulation depth of 12% and passively mode-locked fiber lasing with pulse duration down to 970 fs. © 2015 Elsevier Ltd. (34 refs.)Main Heading: GrapheneControlled terms: Coatings - Micromanipulators - Modulation - Passive mode locking - Saturable absorbers - Semiconductor quantum wellsUncontrolled terms: Effective approaches - High transmission - Micro manipulation - Micrometer scale - Modulation depth - Passively mode-locked - Photonic application - Saturable absorptionClassification Code: 714.2 Semiconductor Devices and Integrated CircuitsSemiconductor Devices and Integrated Circuits - 744.1 Lasers, GeneralLasers, General - 761 NanotechnologyNanotechnology - 804 Chemical Products GenerallyChemical Products Generally - 813.2 Coating MaterialsCoating Materials
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


The degree of polarization modeling with different shapes of the satellite
Yao, Dalei1, 2, 3; Xue, Jianru3; Wen, Desheng1; Qiu, Yuehong1; Xi, Jiangbo1, 2; Wen, Yan1; Chen, Zhi1 Source: Optik, v 127, n 4, p 1860-1866, February 1, 2016
; ISSN: 00304026; DOI: 10.1016/j.ijleo.2015.09.172;
Publisher: Elsevier GmbHAuthor affiliation: 1 Xi'An Institute of Optics and Precision Mechanics of CAS, Xi'an, China2 University of Chinese Academy of Sciences, Beijing, China3 Xi'An Jiaotong University, Xi'an, China
Abstract: Polarization is one of the important characteristics of the interaction between light and substance, which relates to the shape and the material of the target. To research the effects of the degree of polarization (DOP) caused by different materials, the polarized bidirectional reflectance distribution function (pBRDF) model has been established by the theory of microfacet. But in this model, the scattering effect of polyhedron is ignored. Based on these researches, the DOP model of satellite with different shapes (cuboid, cylinder and sphere) is set up and simulated. The simulating results show that the DOP of satellite relates with the complex refractive index, shape of satellite, incident angle and view angle. It is also proved that the polarization is a reflection of the characteristics of material, shape of satellite, which provides theoretical support for identifying satellite. © 2015 Elsevier GmbH. (12 refs.)Main Heading: SatellitesControlled terms: Distribution functions - Polarization - Refractive indexUncontrolled terms: Bidirectional reflectance distribution functions - Complex refractive index - Degree of polarization - Different shapes - Incident angles - Microfacets - Scattering effects - View anglesClassification Code: 655.2 SatellitesSatellites - 741.1 Light/OpticsLight/Optics - 922.1 Probability TheoryProbability Theory
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Design of thermal vacuum quasi-accelerated life test for space two-axis gimbal
Shangguan, Ai-Hong1, 2; Zhang, Hao-Su1, 2; Wang, Chen-Jie1, 3; Qin, De-Jin1; Liu, Zhao-Hui1 Source: Jilin Daxue Xuebao (Gongxueban)/Journal of Jilin University (Engineering and Technology Edition), v 46, n 1, p 186-192, January 1, 2016; Language: Chinese
; ISSN: 16715497; DOI: 10.13229/j.cnki.jdxbgxb201601028;
Publisher: Editorial Board of Jilin UniversityAuthor affiliation: 1 Xi'an Institute of Optics and Precision Mechanics of CAS, Xi'an, China2 University of Chinese Academy of Sciences, Beijing, China3 Key Laboratory of Thermo-fluid Science and Engineering of MOE, Xi'an Jiaotong University, Xi'an, China
Abstract: The domestic and abroad thermal vacuum quasi-accelerated life tests of two-axis gimbals are investigated. It is shown that almost all the tests are focused on the parts rather than on a full gimbal, which can not reflect the performance of the full gimbal. According to the analysis of the structure and lubrication mode of the thermal vacuum quasi-accelerated life tests of two-axis gimbals, the five main elements and their design methods are determined. The test contents and methods are designed for the motion performance examination of a full gimbal, and the failure criterion is given to control the test process. A thermal vacuum quasi-accelerated life test is designed in accordance with the design method of the element design method. A series of test data about the motion performance of the two-axis gimbal is acquired by experiments, which can evaluate the in-orbit life of the space two-axis gimbal. The in-orbit application of the obtained results demonstrate that the designed thermal vacuum quasi-accelerated life test method for the space two-axis gimbal can satisfy the test requirement and it is effective and feasible. © 2016, Editorial Board of Jilin University. All right reserved. (6 refs.)Main Heading: TestingControlled terms: Design - OrbitsUncontrolled terms: Experimental technology of aerocraft - Life-tests - Quasi-accelerated - Thermal vacuum - Two-axis
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Broadband antireflective double-layer mesoporous silica coating with strong abrasion-resistance for solar cell glass
Wang, Jing1, 4; Yang, Chunming3; Liu, Yi3; Zhang, Ce1, 4; Zhang, Cong1, 4; Wang, Mengchao1, 4; Zhang, Jing1, 4; Cui, Xinmin1, 4; Ding, Ruimin1; Xu, Yao2 Source: RSC Advances, v 6, n 30, p 25191-25197, 2016; E-ISSN: 20462069; DOI: 10.1039/c6ra02281b;
Publisher: Royal Society of ChemistryAuthor affiliation: 1 Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan; Shanxi, China2 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; Shaanxi, China3 Shanghai Synchrotron Radiation Facility, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai, China4 University of Chinese Academy of Sciences, Beijing, China
Abstract: To enhance the efficiency of solar cells, a broadband double-layer antireflective (AR) coating with excellent transmittance and abrasion-resistance, was successfully fabricated using two layer mesoporous silica coatings. Both layers were prepared via a solvent evaporation self-assembly method in which the top- and bottom-layer mesoporous silica coatings used Pluronic F127 and cetyltrimethylammonium bromide (CTAB) as templates, respectively. The grazing incidence small angle X-ray scattering (GISAXS) and the transmission electron microscope (TEM) results indicated that the mesopores in the double-layer AR coating belonged to a Fmmm orthorhombic symmetry structure of the SBA-16 in the top layer and a P6/mmc 3D-hexagonal structure of the MCM-41 in the bottom layer. The solar-weighted average transmittance (TPV) of the broadband AR coating is approximately 99.10% on quartz, 98.62% on borosilicate glass, and 98.55% on K9 glass in the solar spectrum range of 300-2400 nm. By introducing broadband AR coating, the overall power conversion efficiency (η) of the solar cell showed an increase of 1.23% for quartz, 1.31% for borosilicate glass, and 1.37% for K9 glass. Meanwhile, the double-layer AR coating had excellent mechanical stability; the TPVvalue of coating after abrasion by CS-10F wearaser only decreased 0.16% on quartz, 0.29% on borosilicate glass and K9 glass. The pencil hardness of the double-layer AR coating was found to be 6H. © The Royal Society of Chemistry 2016. (36 refs.)Main Heading: Borosilicate glassControlled terms: Abrasion - Coatings - Efficiency - Mechanical stability - Mesoporous materials - Quartz - Self assembly - Silica - Solar cells - Transmission electron microscopy - Tribology - Wear resistance - X ray scatteringUncontrolled terms: Anti reflective coatings - Broadband AR coatings - Cetyltrimethylammonium bromide - Grazing incidence small-angle X-ray scattering - Orthorhombic symmetry - Overall power conversion efficiency - Self-assembly method - Solvent evaporationClassification Code: 482.2 MineralsMinerals - 702.3 Solar CellsSolar Cells - 812.3 GlassGlass - 813.2 Coating MaterialsCoating Materials - 913.1 Production EngineeringProduction Engineering - 931 Classical Physics; Quantum Theory; RelativityClassical Physics; Quantum Theory; Relativity - 931.2 Physical Properties of Gases, Liquids and SolidsPhysical Properties of Gases, Liquids and Solids - 932.1 High Energy PhysicsHigh Energy Physics - 951 Materials ScienceMaterials Science
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Cooled Dyson long-wave infrared push-broom imaging spectrometer by re-imaging
Sun, Jiayin1, 2; Liu, Ying1; Jiang, Yang1; Li, Chun1; Sun, Qiang1; Hu, Xinrong3 Source: Optics Communications, v 367, p 274-278, May 15, 2016
; ISSN: 00304018; DOI: 10.1016/j.optcom.2016.01.067;
Publisher: ElsevierAuthor affiliation: 1 Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun, Jilin, China2 Grduate University of Chinese Academy of Sciences, Beijing, China3 Xian Institute of Optics and Precision Mechanics of CAS, Xian, China
Abstract: A cooled long-wave infrared push-broom imaging spectrometer with an F-number of 2 was designed based on the Dyson configuration. A three-mirror off-axis aspherical optical system that provided excellent slit-shaped images was selected as the fore telescope objective. The re-imaging method was applied to obtain a cold stop efficiency of 100%, and the corrector lens in traditional Dyson imaging spectrometers was replaced with re-imaging lenses to correct spherical aberrations. The designed imaging spectrometer provided a spectral resolution of 25 nm at a range of 8-12 μm and possessed a relatively small volume. © 2016 Elsevier B.V. All rights reserved. (14 refs.)Main Heading: Infrared radiationControlled terms: Infrared devices - Optical systems - SpectrometersUncontrolled terms: Aspherical optical systems - Cold stop - Dyson configuration - Imaging lens - Imaging method - Imaging spectrometers - Long wave infrared - Spherical aberrationsClassification Code: 741.1 Light/OpticsLight/Optics - 741.3 Optical Devices and SystemsOptical Devices and Systems
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Effect of different parameters on machining of SiC/SiC composites via pico-second laser
Li, Weinan1; Zhang, Ruoheng1; Liu, Yongsheng2; Wang, Chunhui2; Wang, Jing2; Yang, Xiaojun1; Cheng, Laifei2 Source: Applied Surface Science, v 364, p 378-387, February 28, 2016
; ISSN: 01694332; DOI: 10.1016/j.apsusc.2015.12.089;
Publisher: ElsevierAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; Shaanxi, China2 Science and Technology on Thermostructure Composite Materials Laboratory, Northwestern Polytechnical University, Xi'an; Shaanxi, China
Abstract: Pico-second laser plays an important role in modern machining technology, especially in machining high hardness materials. In this article, pico-second laser was utilized for irradiation on SiC/SiC composites, and effects of different processing parameters including the machining modes and laser power were discussed in detail. The results indicated that the machining modes and laser power had great effect on machining of SiC/SiC composites. Different types of surface morphology and structure were observed under helical line scanning and single ring line scanning, and the analysis of their formulation was discussed in detail. It was believed that the machining modes would be responsible to the different shapes of machining results at the same parameters. The processing power shall also influence the surface morphology and quality of machining results. In micro-hole drilling process, large amount of debris and fragments were observed within the micro-holes, and XPS analysis showed that there existed Si-O bonds and Si-C bonds, indicating that the oxidation during processing was incomplete. Other surface morphology, such as pores and pits were discussed as well. © 2015 Elsevier B.V. All rights reserved. (28 refs.)Main Heading: X ray photoelectron spectroscopyControlled terms: Morphology - Scanning electron microscopy - Silicon carbide - Surface morphologyUncontrolled terms: Different shapes - High hardness materials - Laser process - Machining technology - Morphology and structures - Picosecond laser - Processing parameters - SiC/SiC compositesClassification Code: 804.2 Inorganic CompoundsInorganic Compounds - 951 Materials ScienceMaterials Science
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


A discriminative representation for human action recognition
Yuan, Yuan1; Zheng, Xiangtao1, 2; Lu, Xiaoqiang1 Source: Pattern Recognition, v 59, p 88-97, November 1, 2016
; ISSN: 00313203; DOI: 10.1016/j.patcog.2016.02.022;
Publisher: Elsevier LtdAuthor affiliation: 1 Center for OPTical IMagery Analysis and Learning (OPTIMAL), State Key Laboratory of Transient Optics and Photonics, Xi׳an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi׳an, Shaanxi; 710119, China2 University of the Chinese Academy of Sciences, 19A Yuquanlu, Beijing; 100049, China
Abstract: Action recognition has been standing as an active research topic over the past years. Many efforts have been made and many methods have been proposed. However, there are still some challenges such as illumination condition, viewpoint, camera motion and cluttered background. In order to tackle these challenges, a discriminative representation is proposed by discovering key information of the input data. This task can be addressed by improvements of two major components: parameterized representation and discriminative classifier. The representation is parameterized with hidden variables and can be learned from training data. And the classifier can be trained to recognize actions based on the proposed representation. The contributions of this paper are as follows: (1) a novel probabilistic representation is utilized to capture the relative significant information of low level features; (2) a novel framework is proposed by combining the parameterized representation and discriminative classifier; (3) an alternating strategy is favorable to improve the performance of action recognition by updating the representation and the classifier alternatively. Experimental results on five well-known datasets demonstrate that the proposed method significantly improves the performance in action recognition. © 2016 Elsevier Ltd (58 refs.)Main Heading: Classification (of information)Controlled terms: Classifiers - Gesture recognition - Maximum likelihood - Motion estimation - ParameterizationUncontrolled terms: Action recognition - Cluttered backgrounds - Discriminative classifiers - Discriminative representation - Human-action recognition - Illumination conditions - Low-level features - Probabilistic representation
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Experimental investigation on laser performance of distributed side-pumping fiber amplifier
Gao, Cong1; Ni, Li1; Wang, Xiaolong1; Wang, Yuying1; Wang, Zhen1, 2, 3; Peng, Kun1, 2, 3; Huang, Zhihua1; Wang, Jianjun1; Jing, Feng1; Lin, Aoxiang1 Source: 2015 11th Conference on Lasers and Electro-Optics Pacific Rim, CLEO-PR 2015, v 4, January 7, 2016, 2015 11th Conference on Lasers and Electro-Optics Pacific Rim, CLEO-PR 2015; ISBN-13: 9781467371094; DOI: 10.1109/CLEOPR.2015.7376298; Article number: 7376298; Conference: 11th Conference on Lasers and Electro-Optics Pacific Rim, CLEO-PR 2015, August 24, 2015 - August 28, 2015;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 Research Center of Laser Fusion, China Academy of Engineering Physics, Mianyang, China2 State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics (XIOPM), Chinese Academy of Sciences (CAS), Xi'an, China3 Graduate School of Chinese Academy of Sciences (CAS), Beijing, China
Abstract: 1+1 type distributed-side pumping active fibers were fabricated. Pumped with 976nm LD, over 1kW output power was achieved at 1064nm and 581W power was launched into the coupling unit via one port. © 2015 IEEE. (6 refs.)Main Heading: Pumping (laser)Controlled terms: Fiber amplifiersUncontrolled terms: Active fibers - Experimental investigations - Laser performance - Output power - Side pumpingClassification Code: 744.1 Lasers, GeneralLasers, General - 744.4 Solid State LasersSolid State Lasers
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Design of and experiment on the polarization dehazing imaging system
Xia, Pu1, 2; Liu, Xuebin1; Yan, Peng1 Source: Xi'an Dianzi Keji Daxue Xuebao/Journal of Xidian University, v 43, n 2, p 95-101, April 1, 2016; Language: Chinese
; ISSN: 10012400; DOI: 10.3969/j.issn.1001-2400.2016.02.017;
Publisher: Science PressAuthor affiliation: 1 Key Laboratory of Spectral Imaging Technology, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China2 University of Chinese Academy of Sciences, Beijing; 100049, China
Abstract: In view of the requirement of image quality, integration level and real-time application of the imaging systems under fog weather, this paper reports a polarization imaging system with a dehazing ability. The differential signal is converted by FPGA, and a highly integrated CMOS imaging circuit is built based on the internal PLL of the image sensor and the CamLink protocol. The obtained image is inversed by stokes equations, and the real-time dehazing algorithm is realized by the built-in DSP module. The total size of the polarization imaging system is 117 mm×117 mm×126 mm, and the weight of the system is 1.2 kg. An imaging experiment was made under fog weather, and the dehazing ability of the imaging system is proved by the contrast of the original image and the dehazed image's histogram and RGB distribution. Experimental results show that the imaging system can stably obtain a color dehazed image at 2 048×2 048 @ 180 Hz. © 2016, Science Press. All right reserved. (12 refs.)Main Heading: DemulsificationControlled terms: CMOS integrated circuits - Digital signal processors - Field programmable gate arrays (FPGA) - Fog - Fog dispersal - Imaging systems - Integrated circuit design - Metals - MOS devices - Oxide semiconductors - Polarization - Real time systems - Signal processingUncontrolled terms: Complementary metal oxide semiconductors - Differential signal - Field programmables - Imaging experiments - Integration levels - Polarization imaging - Polarization measurements - Real-time applicationClassification Code: 443.1 Atmospheric PropertiesAtmospheric Properties - 714.2 Semiconductor Devices and Integrated CircuitsSemiconductor Devices and Integrated Circuits - 716.1 Information Theory and Signal ProcessingInformation Theory and Signal Processing - 721.2 Logic ElementsLogic Elements - 722.4 Digital Computers and SystemsDigital Computers and Systems - 746 Imaging TechniquesImaging Techniques - 802.3 Chemical OperationsChemical Operations
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Free-form optical elements corrected aberrations of optical system
Pang, Zhihai1; Fan, Xuewu1; Ma, Zhen1; Zou, Gangyi1 Source: Guangxue Xuebao/Acta Optica Sinica, v 36, n 5, May 10, 2016; Language: Chinese
; ISSN: 02532239; DOI: 10.3788/AOS201636.0522001; Article number: 0522001;
Publisher: Chinese Optical SocietyAuthor affiliation: 1 Space Optics Laboratory, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; Shaanxi; 710119, China
Abstract: The optical element of free-form surface can be expressed by the fringe Zernike polynomial and the terms of initial spherical sag, coma and astigmatism are transformed into the vector forms. Based on the vector wave aberration theory, the free-form optical element characteristic of optical system initial aberration correction is analyzed. Through the analysis, the free-form surfaces in optical system have different aberration emendation specialties at different positions. The free-form optical element can be corrected in full field of view for constant initial aberration as a stop aperture (entrance pupil or exit pupil) in optical system. When the free-form surface is far from the stop aperture of optical system, due to the scaling and offset of the imaging beam aperture for an off-axis field point, the free-form surface can correcte the asymmetric initial aberration, and the relationship of different initial aberration and field of view is different. © 2016, Chinese Lasers Press. All right reserved. (11 refs.)Main Heading: Optical systemsControlled terms: Aberrations - Adaptive optics - Optical design - Surface measurementUncontrolled terms: Aberration correction - Entrance pupil - Exit pupil - Field of views - Field points - Free-form surface - Vector waves - Zernike polynomialsClassification Code: 741.1 Light/OpticsLight/Optics - 741.3 Optical Devices and SystemsOptical Devices and Systems - 943.2 Mechanical Variables MeasurementsMechanical Variables Measurements
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Spatiotemporal Statistics for Video Quality Assessment
Li, Xuelong1; Guo, Qun1; Lu, Xiaoqiang1 Source: IEEE Transactions on Image Processing, v 25, n 7, p 3329-3342, July 2016
; ISSN: 10577149; DOI: 10.1109/TIP.2016.2568752; Article number: 7469872;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 Center for OPTical IMagery Analysis and Learning (OPTIMAL), State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Xi'an , Shaanxi; 710119, China
Abstract: It is an important task to design models for universal no-reference video quality assessment (NR-VQA) in multiple video processing and computer vision applications. However, most existing NR-VQA metrics are designed for specific distortion types, which are not often aware in practical applications. A further deficiency is that the spatial and temporal information of videos is hardly considered simultaneously. In this paper, we propose a new NR-VQA metric based on the spatiotemporal natural video statistics in 3D discrete cosine transform (3D-DCT) domain. In the proposed method, a set of features are first extracted based on the statistical analysis of 3D-DCT coefficients to characterize the spatiotemporal statistics of videos in different views. These features are used to predict the perceived video quality via the efficient linear support vector regression model afterward. The contributions of this paper are: 1) we explore the spatiotemporal statistics of videos in the 3D-DCT domain that has the inherent spatiotemporal encoding advantage over other widely used 2D transformations; 2) we extract a small set of simple but effective statistical features for video visual quality prediction; and 3) the proposed method is universal for multiple types of distortions and robust to different databases. The proposed method is tested on four widely used video databases. Extensive experimental results demonstrate that the proposed method is competitive with the state-of-Art NR-VQA metrics and the top-performing full-reference VQA and reduced-reference VQA metrics. © 1992-2012 IEEE. (51 refs.)Main Heading: Video signal processingControlled terms: Computer vision - Discrete cosine transforms - Image coding - Regression analysis - StatisticsUncontrolled terms: 3D-DCT - natural video - No references - Spatio-temporal statistics - Video quality assessmentClassification Code: 716.4 Television Systems and EquipmentTelevision Systems and Equipment - 723.5 Computer ApplicationsComputer Applications - 921.3 Mathematical TransformationsMathematical Transformations - 922.2 Mathematical StatisticsMathematical Statistics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Highly efficient spectrally encoded imaging using a 45° tilted fiber grating
Wang, Guoqing1; Wang, Chao1; Yan, Zhijun2, 3; Zhang, Lin2 Source: Optics Letters, v 41, n 11, p 2398-2401, June 1, 2016
; ISSN: 01469592, E-ISSN: 15394794; DOI: 10.1364/OL.41.002398;
Publisher: OSA - The Optical SocietyAuthor affiliation: 1 School of Engineering and Digital Arts, University of Kent, Canterbury; CT2 7NT, United Kingdom2 Aston Institute of Photonic Technologies, Aston University, Birmingham; B4 7ET, United Kingdom3 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China
Abstract: A novel highly efficient, fiber-compatible spectrally encoded imaging (SEI) system using a 45° tilted fiber grating (TFG) is proposed and experimentally demonstrated for the first time, to the best of our knowledge. The TFG serves as an in-fiber lateral diffraction element, eliminating the need for bulky and lossy free-space diffraction gratings in conventional SEI systems. Under proper polarization control, due to the strong tilted reflection, the 45° TFG offers a diffraction efficiency as high as 93.5%. Our new design significantly reduces the volume of the SEI system and improves energy efficiency and system stability. As a proof-ofprinciple experiment, spectrally encoded imaging of a customer-designed sample (9.6 mm x 3.0 mm) using the TFG-based system is demonstrated. The lateral resolution of the SEI system is measured to be 42 μm in our experiment. © 2016 Optical Society of America. (16 refs.)Main Heading: Diffraction gratingsControlled terms: Diffraction - Energy efficiency - Fibers - Seebeck effect - System stabilityUncontrolled terms: Diffraction elements - Free space diffraction gratings - In-fiber - Lateral resolution - Polarization control - Tilted fiber gratingsClassification Code: 525.2 Energy ConservationEnergy Conservation - 701.1 Electricity: Basic Concepts and PhenomenaElectricity: Basic Concepts and Phenomena - 741.3 Optical Devices and SystemsOptical Devices and Systems - 961 Systems ScienceSystems Science
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Generation of multiphoton entangled quantum states by means of integrated frequency combs
Reimer, Christian1; Kues, Michael1; Roztocki, Piotr1; Wetzel, Benjamin1, 2; Grazioso, Fabio1; Little, Brent E.3; Chu, Sai T.4; Johnston, Tudor1; Bromberg, Yaron5, 9; Caspani, Lucia6, 10; Moss, David J.7, 11; Morandotti, Roberto1, 8 Source: Science, v 351, n 6278, p 1176-1180, March 11, 2016
; ISSN: 00368075, E-ISSN: 10959203; DOI: 10.1126/science.aae0509;
Publisher: American Association for the Advancement of ScienceAuthor affiliation: 1 Institut National de la Recherche Scientifique, Énergie Matériaux Télécommunications, 1650 Boulevard Lionel-Boulet, Varennes; QC, Canada2 Department of Physics and Astronomy, University of Sussex, Falmer, Brighton, United Kingdom3 State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Science, Xi'an, China4 Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Hong Kong, Hong Kong5 Department of Applied Physics, Yale University, New Haven; CT, United States6 School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh, United Kingdom7 School of Electrical and Computer Engineering, RMIT University, Melbourne; VA, Australia8 Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu, China9 Racah Institute of Physics, Hebrew University of Jerusalem, Jerusalem, Israel10 Institute of Photonics, Department of Physics, University of Strathclyde, Glasgow, United Kingdom11 Center for Micro-Photonics, Swinburne University of Technology, Hawthorn; VA, Australia
Abstract: Complex optical photon states with entanglement shared among several modes are critical to improving our fundamental understanding of quantum mechanics and have applications for quantum information processing, imaging, and microscopy. We demonstrate that optical integrated Kerr frequency combs can be used to generate several bi-and multiphoton entangled qubits, with direct applications for quantum communication and computation. Our method is compatible with contemporary fiber and quantum memory infrastructures and with chip-scale semiconductor technology, enabling compact, low-cost, and scalable implementations. The exploitation of integrated Kerr frequency combs, with their ability to generate multiple, customizable, and complex quantum states, can provide a scalable, practical, and compact platform for quantum technologies. (31 refs.)Controlled terms: computer system - exploitation - information and communication technology - memory - optical instrument - quantum mechanics - technological changeClassification Code: 901 Geobase: Related TopicsGeobase: Related Topics
Database: GEOBASE
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Query-Adaptive Reciprocal Hash Tables for Nearest Neighbor Search
Liu, Xianglong1; Deng, Cheng2; Lang, Bo1; Tao, Dacheng3; Li, Xuelong4 Source: IEEE Transactions on Image Processing, v 25, n 2, p 907-919, February 1, 2016
; ISSN: 10577149; DOI: 10.1109/TIP.2015.2505180; Article number: 7346481;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 State Key Laboratory of Software Development Environment, Beihang University, Beijing, China2 School of Electronic Engineering, Xidian University, Xi'an, China3 Centre for Quantum Computation and Intelligent Systems, Faculty of Engineering and Information Technology, University of Technology at Sydney, Sydney; NSW, Australia4 State Key Laboratory of Transient Optics and Photonics, Center for Optical Imagery Analysis and Learning, Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, China
Abstract: Recent years have witnessed the success of binary hashing techniques in approximate nearest neighbor search. In practice, multiple hash tables are usually built using hashing to cover more desired results in the hit buckets of each table. However, rare work studies the unified approach to constructing multiple informative hash tables using any type of hashing algorithms. Meanwhile, for multiple table search, it also lacks of a generic query-adaptive and fine-grained ranking scheme that can alleviate the binary quantization loss suffered in the standard hashing techniques. To solve the above problems, in this paper, we first regard the table construction as a selection problem over a set of candidate hash functions. With the graph representation of the function set, we propose an efficient solution that sequentially applies normalized dominant set to finding the most informative and independent hash functions for each table. To further reduce the redundancy between tables, we explore the reciprocal hash tables in a boosting manner, where the hash function graph is updated with high weights emphasized on the misclassified neighbor pairs of previous hash tables. To refine the ranking of the retrieved buckets within a certain Hamming radius from the query, we propose a query-adaptive bitwise weighting scheme to enable fine-grained bucket ranking in each hash table, exploiting the discriminative power of its hash functions and their complement for nearest neighbor search. Moreover, we integrate such scheme into the multiple table search using a fast, yet reciprocal table lookup algorithm within the adaptive weighted Hamming radius. In this paper, both the construction method and the query-adaptive search method are general and compatible with different types of hashing algorithms using different feature spaces and/or parameter settings. Our extensive experiments on several large-scale benchmarks demonstrate that the proposed techniques can significantly outperform both the naive construction methods and the state-of-the-art hashing algorithms. © 1992-2012 IEEE. (50 refs.)Main Heading: Nearest neighbor searchControlled terms: Algorithms - Bins - Data structures - Hash functions - Image retrieval - Query processing - Table lookupUncontrolled terms: Adaptive search method - Binary quantization - Construction method - Discriminative power - Graph representation - Hash table - Locality sensitive hashing - query adaptiveClassification Code: 694.4 StorageStorage - 723.1 Computer ProgrammingComputer Programming - 723.2 Data Processing and Image ProcessingData Processing and Image Processing - 921.5 Optimization TechniquesOptimization Techniques
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Study on the methods of calibrating spectral line position of interference imaging spectrometer
Wei, Yu-Tong1, 2; Liu, Shang-Kuo3; Yan, Ting-Yu1, 2; Li, Qi-Wei1, 2 Source: Wuli Xuebao/Acta Physica Sinica, v 65, n 8, April 20, 2016; Language: Chinese
; ISSN: 10003290; DOI: 10.7498/aps.65.080601; Article number: 080601;
Publisher: Institute of Physics, Chinese Academy of SciencesAuthor affiliation: 1 School of Science, Xi'an Jiaotong University, Xi'an; 710049, China2 Institute of Space Optics, Xi'an Jiaotong University, Xi'an; 710049, China3 Xi'an Institute Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China
Abstract: The principle of interference imaging spectrometer is presented. According to the drift of recovery spectral line position, two representative methods of calibrating the laboratory spectral line position are proposed, and the calibration results and their comparative analyses are given. One method of calibration is to correct the principle, which embarks from parameter selection of interference imaging spectrometer and the analysis of the reason why the spectral line position is drifted. Aiming at the problem that the position of spectral line changes with row, the correction scheme is given to improve the accuracy of spectral line position. For four given laser wavelengths, which are 543.5 nm, 594.1 nm, 612 nm, and 632.8 nm, the root-mean-square (RMS) error of spectral line position is reduced from 28.3914 to 5.5371 after calibration. For the interferometer system which has no dispersion, the accuracy of calibration is better than the dispersion system, and can be the same at all detected wavelengths. In this article, the calibration accuracy of long wave is better than that of short wave, which is dependent on the selection of the initial correction wavelength. This method achieves a kind of universality for interference imaging spectrometer and its calibration parameters provide a convenient way to analyze the instrument indexes. Another calibration method is data processing. It makes up the deficiencies of the method mentioned above: a large number of data are needed and the effect of calibration at short wave is not good enough. The RMS error of spectral line position is reduced to 0.9178, which proves that the calibration has a really high precision. This method is simple and can correct all the detected wavelengths and spectral lines by using two united formula. Though this method is not applicable for all the interference imaging spectrometers, the idea that makes hard things simple is deserving of our attention. We can use it in many other fields. The essence of the method is to change a variable quantity into a slowly varying quantity by algorithms, and then establish the relationship between the slowly varying quantity and the standard value. This idea can always make a substantial increase in efficiency of calibration and has a satisfied accuracy. Each of the two methods has advantages and disadvantages: which method we choose to use is dependent on the effect we want to achieve, and it is better to make their combination. This study provides a theoretical and practical guidance for study, design, modulation, experiment and engineering of interference imaging spectrometers. © 2016 Chinese Physical Society. (31 refs.)Main Heading: CalibrationControlled terms: Data handling - Data processing - Dispersion (waves) - Spectrometers - SpectroscopyUncontrolled terms: Calibration accuracy - Calibration parameters - Interference imaging - Interferometer systems - Method of calibrations - Revision by line - Root-mean-square errors - Spectral lineClassification Code: 723.2 Data Processing and Image ProcessingData Processing and Image Processing - 741.3 Optical Devices and SystemsOptical Devices and Systems
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Generation of cylindrical vector beams based on common-path interferometer with a vortex phase plate
Liang, Yansheng1; Yan, Shaohui1; Yao, Baoli1; Lei, Ming1; Min, Junwei1; Yu, Xianghua1 Source: Optical Engineering, v 55, n 4, April 1, 2016
; ISSN: 00913286, E-ISSN: 15602303; DOI: 10.1117/1.OE.55.4.046117; Article number: 046117;
Publisher: SPIEAuthor affiliation: 1 Xi'An Institute of Optics and Precision Mechanics, State Key Laboratory of Transient Optics and Photonics, Chinese Academy of Sciences, No. 17, Xinxi Road, High-Tech Zone, Xi'an; 710119, China
Abstract: Cylindrical vector (CV) beams have found increasing applications in physics, biology, and chemistry. To generate CV beams, interferometric technique is popularly adopted due to its flexibility. However, most interferometric configurations for the generation of CV beams are faced with system instability arising from external disturbance, limiting their practical applications. A common-path interferometer for the generation of radially and azimuthally polarized beams is proposed to improve the system stability. The optical configuration consists of a vortex phase plate acting to tailor the phase profile and a cube nonpolarizing beamsplitter to split the input beam into two components with mirror-like spiral phase distribution. The generated CV beams show a high quality in polarization and exhibit a better stability of beam profile than those obtained by noncommon-path interferometric configurations. © 2016 Society of Photo-Optical Instrumentation Engineers (SPIE). (39 refs.)Main Heading: InterferometryControlled terms: Interferometers - Optical beam splitters - Polarization - System stability - Vortex flow - Wave interferenceUncontrolled terms: Azimuthally polarized beams - Common-path interferometers - Cylindrical vector beam - Electromagnetic optics - Interferometric configuration - Interferometric techniques - Optical configurations - Singular opticsClassification Code: 631.1 Fluid Flow, GeneralFluid Flow, General - 741.3 Optical Devices and SystemsOptical Devices and Systems - 941.3 Optical InstrumentsOptical Instruments - 941.4 Optical Variables MeasurementsOptical Variables Measurements - 961 Systems ScienceSystems Science
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Semantic photo retargeting under noisy image labels
Zhang, Luming1; Li, Xuelong2; Nie, Liqiang3; Yan, Yan4; Zimmermann, Roger3 Source: ACM Transactions on Multimedia Computing, Communications and Applications, v 12, n 3, May 2016
; ISSN: 15516857, E-ISSN: 15516865; DOI: 10.1145/2886775; Article number: 37;
Publisher: Association for Computing MachineryAuthor affiliation: 1 Department of CSIE, Hefei University of Technology, 193 Tunxi Rd, Hefei, China2 Center for OPTical IMagery Analysis and Learning (OPTIMAL), Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, Shaanxi; 710119, China3 School of Computing, National University of Singapore, 13 Computing Drive, 117417, Singapore4 Department of Information Engineering and Computer Science, University of Trento, Via Sommarive, 9, Trento; 38123, Italy
Abstract: With the popularity of mobile devices, photo retargeting has become a useful technique that adapts a high-resolution photo onto a low-resolution screen. Conventional approaches are limited in two aspects. The first factor is the de-emphasized role of semantic content that is many times more important than lowlevel features in photo aesthetics. Second is the importance of image spatial modeling: Toward a semantically reasonable retargeted photo, the spatial distribution of objects within an image should be accurately learned. To solve these two problems, we propose a new semantically aware photo retargeting that shrinks a photo according to region semantics. The key technique is a mechanism transferring semantics of noisy image labels (inaccurate labels predicted by a learner like an SVM) into different image regions. In particular, we first project the local aesthetic features (graphlets in this work) onto a semantic space, wherein image labels are selectively encoded according to their noise level. Then, a category-sharing model is proposed to robustly discover the semantics of each image region. The model is motivated by the observation that the semantic distribution of graphlets from images tagged by a common label remains stable in the presence of noisy labels. Thereafter, a spatial pyramid is constructed to hierarchically encode the spatial layout of graphlet semantics. Based on this, a probabilistic model is proposed to enforce the spatial layout of a retargeted photo to be maximally similar to those from the training photos. Experimental results show that (1) noisy image labels predicted by different learners can improve the retargeting performance, according to both qualitative and quantitative analysis, and (2) the category-sharing model stays stable even when 32.36% of image labels are incorrectly predicted. ©2016 ACM. (45 refs.)Main Heading: SemanticsControlled terms: Mobile devicesUncontrolled terms: Aesthetics evaluation - Conventional approach - Graphlet - High-resolution photos - Probabilistic modeling - Qualitative and quantitative analysis - Retargeting - Semantic distributionClassification Code: 716 Telecommunication; Radar, Radio and TelevisionTelecommunication; Radar, Radio and Television
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Visualized measurement of the liquid phase diffusion by using digital holographic interferometry
Wang, Jun1, 2; Yang, Rong1; Zheng, Jiao1; Zhao, Jian-Lin2 Source: Guangzi Xuebao/Acta Photonica Sinica, v 45, n 4, April 1, 2016
; ISSN: 10044213; DOI: 10.3788/gzxb20164504.0412001; Article number: 0412001;
Publisher: Chinese Optical SocietyAuthor affiliation: 1 School of Mechanical and Precision Instrument Engineering, Xi'an University of Technology, Xi'an; 710048, China2 Shaanxi Key Laboratory of Optical Information Technology and the Key Laboratory of Space Applied Physics and Chemistry, School of Science, Northwestern Polytechnical University, Xi'an; 710072, China
Abstract: Liquid phase diffusion is a high energy consumption process in chemical production. With the rapid development of the chemical technology based on liquid phase diffusion, especially in some emerging fields such as biomedicine and environmental science, the microcosmic study on the liquid phase diffusion is becoming more and more important. By applying the digital holographic interferometry, a diffusion process in liquid phase of pure ethanol and water was observed. After recording the digital hologram by a Mach-Zehnder interferometer and reconstructing digital hologram of object beam by the gray scale analysis, the phase variation of object wavefront in the diffusion process at different times and the curves of refractive index change in the diffusion area were both acquired. The result shows that by applying the digital holographic interferometry, a fast, real time and high-accuracy diffusion can be realized. Moreover, this method can be used to realize a remote visual monitoring. In addition, this method combining with wavelength and angular multiplexing techniques can be applied to obtain nonlinear characteristics parameters in multiple-phase diffusion measurements. © 2016, Chinese Optical Society. All right reserved. (16 refs.)Main Heading: DiffusionControlled terms: Computer generated holography - Energy utilization - Environmental technology - Holograms - Holographic interferometry - Holography - Image processing - Interferometry - Liquids - Refractive index - Semiconductor quantum wellsUncontrolled terms: Coherence imaging - Digital holographic interferometry - Digital holography - High energy consumption - Liquid phase diffusion - Nonlinear characteristics - Refractive index changes - Visualized measurementsClassification Code: 454 Environmental EngineeringEnvironmental Engineering - 525.3 Energy UtilizationEnergy Utilization - 714.2 Semiconductor Devices and Integrated CircuitsSemiconductor Devices and Integrated Circuits - 741.1 Light/OpticsLight/Optics - 743 HolographyHolography - 743.1 Holographic TechniquesHolographic Techniques - 941.4 Optical Variables MeasurementsOptical Variables Measurements
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Pixel-to-Model Distance for Robust Background Reconstruction
Yang, Lu1; Cheng, Hong1; Su, Jianan1; Li, Xuelong2 Source: IEEE Transactions on Circuits and Systems for Video Technology, v 26, n 5, p 903-916, May 2016
; ISSN: 10518215; DOI: 10.1109/TCSVT.2015.2424052; Article number: 7088578;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 Center for Robotics, University of Electronic Science and Technology of China, Chengdu; 611731, China2 State Key Laboratory of Transient Optics and Photonics, Center for OPTical IMagery Analysis and Learning, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China
Abstract: Background information is crucial for many video surveillance applications such as object detection and scene understanding. In this paper, we present a novel pixel-to-model (P2M) paradigm for background modeling and restoration in surveillance scenes. In particular, the proposed approach models the background with a set of context features for each pixel, which are compressively sensed from local patches. We determine whether a pixel belongs to the background according to the minimum P2M distance, which measures the similarity between the pixel and its background model in the space of compressive local descriptors. The pixel feature descriptors of the background model are properly updated with respect to the minimum P2M distance. Meanwhile, the neighboring background model will be renewed according to the maximum P2M distance to handle ghost holes. The P2M distance plays an important role of background reliability in the 3-D spatial-temporal domain of surveillance videos, leading to the robust background model and recovered background videos. We applied the proposed P2M distance for foreground detection and background restoration on synthetic and real-world surveillance videos. Experimental results show that the proposed P2M approach outperforms the state-of-the-art approaches both in indoor and outdoor surveillance scenes. © 2015 IEEE. (78 refs.)Main Heading: Object detectionControlled terms: Image segmentation - Monitoring - Object recognition - Pixels - Restoration - Security systemsUncontrolled terms: Background information - Background model - Background reconstruction - Descriptors - Spatial temporal domain - State-of-the-art approach - Video surveillance - Video-surveillance applicationsClassification Code: 723.2 Data Processing and Image ProcessingData Processing and Image Processing - 914.1 Accidents and Accident PreventionAccidents and Accident Prevention
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Investigations on the photoluminescence of the iron and cobalt doped fluoride-containing phosphate-based glasses and its defects-related nature
He, Quanlong1, 2; Wang, Pengfei1; Lu, Min1; Peng, Bo1 Source: Journal of Alloys and Compounds, v 685, p 153-158, November 15, 2016
; ISSN: 09258388; DOI: 10.1016/j.jallcom.2016.05.253;
Publisher: Elsevier LtdAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences (CAS), Xi'an; 710119, China2 University of Chinese Academy of Sciences (UCAS), Beijing; 100049, China
Abstract: The influence of doping iron and cobalt ions on the formation of defects in the fluoride-containing phosphate-based glasses was studied comprehensively by means of analyzing the absorption and photoluminescence (PL) spectra as well as the electron spin resonance (ESR) spectra. The absorption and ESR spectra show that the defects, including phosphate-related oxygen hole center (POHC), oxygen-related hole centers (OHC), Fe3+, Co2+, PO3-EC, PO4-EC and fluorine-related non-paramagnetic color (FD) centers were formed during the glass preparation process. In addition, the analysis on the PL and absorption as well as excitation (PLE) spectra indicate that PO4-EC and OHC defects which have large absorption in the UV region result in the emission band peaking at 780 nm under the excitation at 351 nm for the cobalt doped (2ω absorptive) glass. Addition of small quantities of iron causes the effectively intense absorption towards the 1ω wavelength (1053 nm) due to the presence of Fe2+, but also a distinctively observed red-shift of the UV absorption edge was dominated by the charge-transfer transition of the existence of Fe3+. The experimental results demonstrate that Fe3+suppress the formation of FD defects in the glasses, while promotes the formation of POHC defects. Besides, introduction of Co2+inhibits the formation of POHC and PO4-EC defects, and Fe2+promotes forming of POHC defects. © 2016 Elsevier B.V. All rights reserved. (26 refs.)Main Heading: Electron spin resonance spectroscopyControlled terms: Absorption spectra - Carbon dioxide - Charge transfer - Cobalt - Defects - Doppler effect - Finite difference method - Fluorine compounds - Glass - Iron - Magnetic moments - Photoluminescence - ReductionUncontrolled terms: Absorption and photoluminescence - Charge transfer transitions - Emission bands - Glass preparation - Oxygen hole centers - Phosphate based glass - Photoluminescence spectrum - Red shiftClassification Code: 545.1 IronIron - 549.3 Nonferrous Metals and Alloys excluding Alkali and Alkaline Earth Metals Nonferrous Metals and Alloys excluding Alkali and Alkaline Earth Metals - 701.2 Magnetism: Basic Concepts and PhenomenaMagnetism: Basic Concepts and Phenomena - 711.2 Electromagnetic Waves in Relation to Various StructuresElectromagnetic Waves in Relation to Various Structures - 741.1 Light/OpticsLight/Optics - 801 ChemistryChemistry - 802.2 Chemical ReactionsChemical Reactions - 804.2 Inorganic CompoundsInorganic Compounds - 812.3 GlassGlass - 921.6 Numerical MethodsNumerical Methods - 951 Materials ScienceMaterials Science
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Effect of the gradient constant temperature on the electrochemical capacitance of cotton stalk-based activated carbon
Li, Wenlong1, 2; Wumaier, Tuerdi3; Chen, Mingde1; Zhang, Ji3; Liu, Huan1, 2; Yang, Li Qing1; Wang, Haojing1 Source: Journal of Solid State Electrochemistry, v 20, n 8, p 2315-2321, August 1, 2016
; ISSN: 14328488; DOI: 10.1007/s10008-016-3235-2;
Publisher: Springer New York LLCAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi’an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi’an; Shaanxi; 710119, China2 University of Chinese Academy of Sciences, Beijing; 100049, China3 Xinjiang Institute of Engineering, Urumqi; Xinjiang; 830023, China
Abstract: The cost-effective activated carbon based from waste cotton stalks by the KOH activation method is investigated as the electrode material in supercapacitor for the first time. Activation temperature control is one of the most important factors affecting the surface area and pore structure of activated carbon, and it influences the capacitive performance of activated carbon based from cotton stalk. The optimized conditions are as follows: cotton stalk base charcoals and activating agent with a mass ration of 1:4, at an activation temperature of 600, 700, and 800°C for 1, 1, and 2 h, respectively. With these experimental conditions, the activated carbon presents excellent electrochemical characteristics. The specific capacitance of the prepared activated carbon was as high as 180 F g−1at 2 A g−1in 1.0 mol·L−1Et4NBF4/AN electrolyte and the specific capacitance without obvious attenuation after 2000 cycles. So, it is reasonable to believe that the activated carbons from cotton stalks by the KOH gradient constant temperature activation method might be one of the innovative carbon electrode materials for supercapacitor. © 2016, Springer-Verlag Berlin Heidelberg. (42 refs.)Main Heading: Electrochemical electrodesControlled terms: Activated carbon - Capacitance - Capacitors - Charcoal - Chemical activation - Cost effectiveness - Cotton - Electrochemical properties - Electrodes - Electrolytes - Electrolytic capacitors - Reactor coresUncontrolled terms: Activation temperatures - Capacitive performance - Carbon electrode - Cotton stalk - Electrochemical capacitance - Electrochemical characteristics - Experimental conditions - KOH activation
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Spatiotemporal evolution of the light field inside the microresonator with normal dispersion
Xu, Xin1; Hu, Xiaohong1; Feng, Ye1; Liu, Yuanshan1; Wang, Yishan1; Wei, Ruyi2 Source: Guangxue Xuebao/Acta Optica Sinica, v 36, n 6, June 10, 2016; Language: Chinese
; ISSN: 02532239; DOI: 10.3788/AOS201636.0619001; Article number: 0619001;
Publisher: Chinese Optical SocietyAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; Shaanxi; 710119, China2 Key Laboratory of Spectral Imaging Technology, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; Shaanxi; 710119, China
Abstract: Based on the Lugiato-Lefever equation, the spatiotemporal evolutions in microresonator are discussed respectively, which is pumped by the continuous wave (CW) light as well as the combination of CW light and periodical pulse train simultaneously, and the effect of each parameter on light field is studied. Simulation results indicate that the dark soliton can exist in the microresonator with CW pumped. The width of the dark soliton pulse increases with the dispersion coefficient. The shape of the dark soliton pulse is varied when the frequency detuning is increased. Meanwhile, in the normal dispersion regime, the pulses can form in the microresonator by the use of synthetical pumping manner. The drawback is compensated that the bright soliton pulse is difficult to be generated in the microresonator for single CW pumped of certain parameters configuration. Moreover, the high amplitude of the pump pulses leads to the pulse split, the pulse stretching and the loss of the pulse occur when the frequency detuning of the microresonator rises. Theoretical analysis results are significant for high-quality Kerr optical frequency comb and their practical applications, and they are helpful for selecting the proper microresonator and pump parameters. © 2016, Chinese Lasers Press. All right reserved. (22 refs.)Main Heading: Optical pumpingControlled terms: Dispersion (waves) - Light - Nonlinear equations - Nonlinear optics - Resonators - SolitonsUncontrolled terms: Continuous wave lights - Dispersion coefficient - Light fields - Lugiato-Lefever equation - Micro resonators - Optical frequency combs - Parameters configuration - Spatiotemporal evolutionClassification Code: 741.1 Light/OpticsLight/Optics - 741.1.1 Nonlinear OpticsNonlinear Optics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Influence of temperature on “Smile” in high power diode laser bars
Wang, Shu-Na1; Zhang, Pu1; Xiong, Ling-Ling1; Nie, Zhi-Qiang1; Wu, Di-Hai1; Liu, Xing-Sheng1, 2 Source: Guangzi Xuebao/Acta Photonica Sinica, v 45, n 5, May 1, 2016; Language: Chinese
; ISSN: 10044213; DOI: 10.3788/gzxb20164505.0514001; Article number: 0514001;
Publisher: Chinese Optical SocietyAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China2 Focuslight Technologies Co., LTD, Xi'an; 710077, China
Abstract: By the numerical modeling and experimental test, the influence of temperature on “smile” was studied. By using the finite element method, the thermal stresses induced during bar bonding and operating process were simulated respectively. In simulations, it is assumed that the deformation of the laser bar is only caused by the thermal stress. The simulated results show that the thermal stress across the laser bar decreases with the increasing of heatsink temperature. As thus, the curve of the laser bar induced by packaging thermal stress will decrease with the increasing of the temperature. In this experiment, “smile” of five samples from the same wafer and batch was measured under different heatsink temperatures. Experimental results show that “smile” of the five samples increases or decreases as heatsink temperature increasing. The possible reason which is related with the combined action between the primitive bending shape of the bare bar and the mounting thermal stress. If the bare bar before packaging is flat or convex, “smile” of the diode laser bar will decrease as the heatsink temperature increasing. In addition, if the bare bar is concave and the laser bar is still concave after packaging, “smile” will increase with the increasing of heatsink temperature. © 2016, Science Press. All right reserved. (16 refs.)Main Heading: Finite element methodControlled terms: Diodes - Heat sinks - Lasers - Power semiconductor diodes - Semiconductor lasers - Temperature - Thermal stressUncontrolled terms: Combined actions - Diode laser array - Diode laser bar - Experimental test - High power diode laser - Laser bar - Operating process - Simulated resultsClassification Code: 616.1 Heat Exchange Equipment and ComponentsHeat Exchange Equipment and Components - 641.1 ThermodynamicsThermodynamics - 744.1 Lasers, GeneralLasers, General - 744.4.1 Semiconductor LasersSemiconductor Lasers - 921.6 Numerical MethodsNumerical Methods - 931.2 Physical Properties of Gases, Liquids and SolidsPhysical Properties of Gases, Liquids and Solids
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


34-fs, all-fiber all-polarization-maintaining single-mode pulse nonlinear amplifier
Yu, Jia1, 2, 3; Feng, Ye1, 2, 4; Cai, Yajun1, 2; Li, Xiaohui5; Hu, Xiaohong1, 2; Zhang, Wei1; Duan, Lina1, 2; Yang, Zhi1; Wang, Yishan1, 3; Liu, Yuanshan1; Zhao, Wei1, 3 Source: Optics Express, v 24, n 15, p 16630-16637, July 25, 2016; E-ISSN: 10944087; DOI: 10.1364/OE.24.016630;
Publisher: OSA - The Optical SocietyAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China2 University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing; 100049, China3 Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan; Shanxi; 030006, China4 Department of Physics, Xi'an Jiaotong University, Xi'an; 710049, China5 School of Physics and Information Technology, Shaanxi Normal University, Xi'an; 710062, China
Abstract: We present an all-fiber all-polarization-maintaining (PM) single mode (SM) fiber pulse nonlinear amplification system. The seed laser with a repetition rate of 200 MHz is amplified by two-section erbium-doped PM gain fibers with different peak-absorption rate. The amplified pulse duration can be compressed into 34-fs with 320-mW output power, which corresponds to 1.6-nJ pulse energy and approximate 23.5-kW peak power. In addition, the amplified and compressed pulse is further coupled into the high nonlinear fiber and an octave-spanning supercontinuum generation can be obtained. To the best of our knowledge, it is the highest peak power and the shortest pulse duration obtained in the field of all-fiber all-PM SM pulse-amplification systems. ©2016 Optical Society of America. (22 refs.)Main Heading: Erbium doped fiber amplifiersControlled terms: Amplification - Fiber amplifiers - Fibers - Nonlinear optics - Polarization - Polarization-maintaining fiber - Supercontinuum generationUncontrolled terms: Amplified pulse - Compressed pulse - High nonlinear fibers - Nonlinear amplification - Nonlinear amplifier - Peak absorption - Polarization maintaining - Pulse amplificationClassification Code: 741.1.1 Nonlinear OpticsNonlinear Optics - 741.1.2 Fiber OpticsFiber Optics - 744.4 Solid State LasersSolid State Lasers
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Packaging of hard solder 500W QCW diode laser array
Li, Xiaoning1; Wang, Jingwei1; Hou, Dong1; Nie, Zhiqiang2; Liu, Xingsheng1, 2 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 9730, June 30, 2016, Components and Packaging for Laser Systems II
; ISSN: 0277786X, E-ISSN: 1996756X; ISBN-13: 9781628419658; DOI: 10.1117/12.2213977; Article number: 97300D; Conference: Components and Packaging for Laser Systems II, February 16, 2016 - February 18, 2016;
Publisher: SPIEAuthor affiliation: 1 Focuslight Technologies Inc., 56 Zhangba 6th Road, Xi'an High-Tech Zone, Xi'an, Shaanxi; 710077, China2 State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, No. 17 Xinxi Road New Industrial Park, Xi'an, Shaanxi; 710119, China
Abstract: The package structure critically influences the major characteristics of diode laser, such as thermal behavior, output power, wavelength and smile effect. In this work, a novel micro channel cooler (MCC) for stack array laser with good heat dissipation capability and high reliability is presented. Numerical simulations of thermal management with different MCC structure are conducted and analyzed. Based on this new MCC packaging structure, a series of QCW 500W high power laser arrays with hard solder packaging technology has been fabricated. The performances of the laser arrays are characterized. A narrow spectrum of 3.12 nm and an excellent smile value are obtained. The lifetime of the laser array is more than 1.38×109shots and still ongoing. © 2016 SPIE. (12 refs.)Main Heading: PackagingControlled terms: Diodes - High power lasers - Semiconductor lasersUncontrolled terms: Heat dissipation capability - High power - High reliability - Microchannel coolers - Package structure - Packaging structure - Packaging technologies - Thermal behaviorsClassification Code: 694.1 Packaging, GeneralPackaging, General - 744.1 Lasers, GeneralLasers, General - 744.4.1 Semiconductor LasersSemiconductor Lasers
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


High power diode laser array development using completely indium free packaging technology with narrow spectrum
Hou, Dong1; Wang, Jingwei1; Gao, Lijun1; Liang, Xuejie1; Li, Xiaoning1; Liu, Xingsheng1, 2 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 9730, June 30, 2016, Components and Packaging for Laser Systems II
; ISSN: 0277786X, E-ISSN: 1996756X; ISBN-13: 9781628419658; DOI: 10.1117/12.2213928; Article number: 973009; Conference: Components and Packaging for Laser Systems II, February 16, 2016 - February 18, 2016;
Publisher: SPIEAuthor affiliation: 1 Focuslight Technologies Inc., 56 Zhangba 6th Road, Xi'an, Shaanxi; 710077, China2 State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, No. 17 Xinxi Road, Xi'an, Shaanxi; 710119, China
Abstract: The high power diode lasers have been widely used in many fields. In this work, a sophisticated high power and high performance horizontal array of diode laser stacks have been developed and fabricated with high duty cycle using hard solder bonding technology. CTE-matched submount and Gold Tin (AuSn) hard solder are used for bonding the diode laser bar to achieve the performances of anti-thermal fatigue, higher reliability and longer lifetime. This array consists of 30 bars with the expected optical output peak power of 6000W. By means of numerical simulation and analytical results, the diode laser bars are aligned on suitable positions along the water cooled cooler in order to achieve the uniform wavelength with narrow spectrum and accurate central wavelength. The performance of the horizontal array, such as output power, spectrum, thermal resistance, life time, etc., is characterized and analyzed. © 2016 SPIE. (10 refs.)Main Heading: Semiconductor lasersControlled terms: Diodes - Laser beam welding - Power semiconductor diodesUncontrolled terms: Analytical results - Central wavelength - Diode laser bar - Diode laser stack - High power diode laser - High-power diode laser arrays - Horizontal arrays - Packaging technologiesClassification Code: 744.4.1 Semiconductor LasersSemiconductor Lasers - 744.9 Laser ApplicationsLaser Applications
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Thermal/structural/optical integrated design for optical sensor mounted on unmanned aerial vehicle
Zhang, Gaopeng1; Yang, Hongtao1, 2; Mei, Chao1; Wu, Dengshan1; Shi, Kui1 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 9796, 2016, Selected Papers of the Photoelectronic Technology Committee Conferences held November 2015
; ISSN: 0277786X, E-ISSN: 1996756X; ISBN-13: 9781628418811; DOI: 10.1117/12.2229726; Article number: 97962R; Conference: International Symposia on Atmosphere Optics and Adaptive Optics, Testing and Driving of Laser Fusion Energy Technology, High-performance Special Optical Film Technology, Novel Navigation Technology, Monitoring, Early Warning, Removal Technology of Space Targets and Debris, and UAV Payload Technology, November 15, 2015 - November 28, 2015; Sponsor: Chinese Academy of Engineering; Chinese Society for Optical Engineering; National Natural Science Foundation of China;
Publisher: SPIEAuthor affiliation: 1 Xi'an Institute of Optics and Precision Mechanics, CAS, Xi'an; 710119, China2 Graduate School of Chinese Academy of Sciences, Beijing; 100864, China
Abstract: With the rapid development of science and technology and the promotion of many local wars in the world, altitude optical sensor mounted on unmanned aerial vehicle is more widely applied in the airborne remote sensing, measurement and detection. In order to obtain high quality image of the aero optical remote sensor, it is important to analysis its thermal-optical performance on the condition of high speed and high altitude. Especially for the key imaging assembly, such as optical window, the temperature variation and temperature gradient can result in defocus and aberrations in optical system, which will lead to the poor quality image. In order to improve the optical performance of a high speed aerial camera optical window, the thermal/structural/optical integrated design method is developed. Firstly, the flight environment of optical window is analyzed. Based on the theory of aerodynamics and heat transfer, the convection heat transfer coefficient is calculated. The temperature distributing of optical window is simulated by the finite element analysis software. The maximum difference in temperature of the inside and outside of optical window is obtained. Then the deformation of optical window under the boundary condition of the maximum difference in temperature is calculated. The optical window surface deformation is fitted in Zernike polynomial as the interface, the calculated Zernike fitting coefficients is brought in and analyzed by CodeV Optical Software. At last, the transfer function diagrams of the optical system on temperature field are comparatively analyzed. By comparing and analyzing the result, it can be obtained that the optical path difference caused by thermal deformation of the optical window is 138.2 nm, which is under PV ≤1/4λ. The above study can be used as an important reference for other optical window designs. © 2016 SPIE. (10 refs.)Main Heading: Adaptive opticsControlled terms: Aerodynamic heating - Aerodynamics - Deformation - Design - Finite element method - Heat convection - Heat transfer - Optical design - Optical sensors - Optical systems - Quality control - Remote sensing - Space debris - Temperature - Unmanned aerial vehicles (UAV) - VehiclesUncontrolled terms: Airborne remote sensing - Development of science and technologies - Finite element analysis software - Optical path difference - Optical remote sensors - Optical window - Temperature distributing - Thermal/structural/optical integratedClassification Code: 641.1 ThermodynamicsThermodynamics - 641.2 Heat TransferHeat Transfer - 651.1 Aerodynamics, GeneralAerodynamics, General - 652.1 Aircraft, GeneralAircraft, General - 656.1 Space FlightSpace Flight - 741.1 Light/OpticsLight/Optics - 741.3 Optical Devices and SystemsOptical Devices and Systems - 913.3 Quality Assurance and ControlQuality Assurance and Control - 921.6 Numerical MethodsNumerical Methods
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Optimization design about gimbal structure of high-precision autonomous celestial navigation tracking mirror system
Huang, Wei1; Yang, Xiao-Xu1; Han, Jun-Feng1; Wei, Yu1; Zhang, Jing1; Xie, Mei-Lin1; Yue, Peng2 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 9796, 2016, Selected Papers of the Photoelectronic Technology Committee Conferences held November 2015
; ISSN: 0277786X, E-ISSN: 1996756X; ISBN-13: 9781628418811; DOI: 10.1117/12.2229022; Article number: 97961S; Conference: International Symposia on Atmosphere Optics and Adaptive Optics, Testing and Driving of Laser Fusion Energy Technology, High-performance Special Optical Film Technology, Novel Navigation Technology, Monitoring, Early Warning, Removal Technology of Space Targets and Debris, and UAV Payload Technology, November 15, 2015 - November 28, 2015; Sponsor: Chinese Academy of Engineering; Chinese Society for Optical Engineering; National Natural Science Foundation of China;
Publisher: SPIEAuthor affiliation: 1 Xi'an Institute of Optics and Precision Mechanics, CAS, Xi'an; 710119, China2 China Huay in Ordnance Test Center, Huayin Shaanxi; 714200, China
Abstract: High precision tracking platform of celestial navigation with control mirror servo structure form, to solve the disadvantages of big volume and rotational inertia, slow response speed, and so on. It improved the stability and tracking accuracy of platform. Due to optical sensor and mirror are installed on the middle-gimbal, stiffness and resonant frequency requirement for high. Based on the application of finite element modality analysis theory, doing Research on dynamic characteristics of the middle-gimbal, and ANSYS was used for the finite element dynamic emulator analysis. According to the result of the computer to find out the weak links of the structure, and Put forward improvement suggestions and reanalysis. The lowest resonant frequency of optimization middle-gimbal avoid the bandwidth of the platform servo mechanism, and much higher than the disturbance frequency of carrier aircraft, and reduces mechanical resonance of the framework. Reaching provides a theoretical basis for the whole machine structure optimization design of high-precision of autonomous Celestial navigation tracking mirror system. © 2016 SPIE. (5 refs.)Main Heading: Structural optimizationControlled terms: Adaptive optics - Dynamics - Finite element method - Mirrors - Natural frequencies - Navigation - Shape optimization - Space debrisUncontrolled terms: Application of finite elements - Celestial navigation - Disturbance frequency - High precision tracking - Mechanical resonance - Optimization design - Rotational inertia - Stability and trackingClassification Code: 656.1 Space FlightSpace Flight - 741.1 Light/OpticsLight/Optics - 741.3 Optical Devices and SystemsOptical Devices and Systems - 921.5 Optimization TechniquesOptimization Techniques - 921.6 Numerical MethodsNumerical Methods
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Surveillance video synopsis via scaling down objects
Li, Xuelong1; Wang, Zhigang2; Lu, Xiaoqiang1 Source: IEEE Transactions on Image Processing, v 25, n 2, p 740-755, February 1, 2016
; ISSN: 10577149; DOI: 10.1109/TIP.2015.2507942; Article number: 7353185;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 Center for OPTical IMagery Analysis and Learning (OPTIMAL), State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Xi'an, Shaanxi; 710119, China2 School of Computer Science and Center for OPTical IMagery Analysis and Learning (OPTIMAL), Northwestern Polytechnical University, Xi'an, Shaanxi; 710072, China
Abstract: Video synopsis is an effective technique to provide a compact representation of the original video by removing spatiotemporal redundancies and by preserving the essential activities. Most current approaches for video synopsis will cause collisions among objects, especially when the video is condensed much. In this paper, we present an approach for video synopsis to reduce the collisions. Our approach first shifts active objects along the time axis to compact the original video. Then, the sizes of the objects are reduced when collisions occur. Meanwhile, the geometric centroids of the objects will be kept unchanged to preserve the location information. Our contributions are threefold. First, an approach is proposed to decrease collisions in the synopsis video through reducing the sizes of the objects. Second, an optimization framework is developed to indicate the optimal time position and the appropriate reduction coefficient for each object. Finally, some metrics are proposed, and several experiments are carried out to evaluate the proposed approach. The experiments have demonstrated that the synopsis video produced by our approach has much fewer collisions while the compression ratio is high. © 2015 IEEE. (53 refs.)Main Heading: Security systemsControlled terms: Compression ratio (machinery) - Optimization - Space surveillanceUncontrolled terms: Compact representation - Location information - Optimization framework - reduce collision - reduce size - Reduction coefficient - Surveillance video - Video synopsisClassification Code: 656.2 Space ResearchSpace Research - 914.1 Accidents and Accident PreventionAccidents and Accident Prevention - 921.5 Optimization TechniquesOptimization Techniques
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


A phase estimation algorithm for optical linear sampling
Li, Fei-Tao1, 2; Zhao, Wei1; Liu, Yuan-Shan1 Source: Guangzi Xuebao/Acta Photonica Sinica, v 45, n 8, August 1, 2016
; ISSN: 10044213; DOI: 10.3788/gzxb20164508.0806002; Article number: 0806002;
Publisher: Chinese Optical SocietyAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics of CAS, Xi'an; 710119, China2 University of Chinese Academy of Sciences, Beijing; 100039, China
Abstract: An improved Blind Phase Search algorithm was proposed. In this algorithm, carrier phase noise was estimated by searching minimum Euler distance twice. To verify this algorithm, an optical linear sampling simulation system was set up. The constellation diagram of 10Gbaud/s 16QAM signal was simulated by using an optical frequency comb with pulse width of 500fs and duration of 10ns as optical sampling source. The simulation result shows that, the phase noise between the signal source and optical sampling source can be compensated effectively by this algorithm when the sum linewidth of the two lasers is less than 10MHz. Finally, the constellation diagram of 10Gbaud/s 16QAM signal is displayed clearly. © 2016, Science Press. All right reserved. (21 refs.)Main Heading: AlgorithmsControlled terms: Digital signal processing - Modulation - Optical communication - Phase noise - Quadrature amplitude modulation - Signal processing - Signal samplingUncontrolled terms: Carrier phase - Constellation diagrams - Linear sampling - Optical coherent communications - Optical frequency combs - Optical sampling - Phase estimation algorithms - Search AlgorithmsClassification Code: 701.2 Magnetism: Basic Concepts and PhenomenaMagnetism: Basic Concepts and Phenomena - 716.1 Information Theory and Signal ProcessingInformation Theory and Signal Processing - 717.1 Optical Communication SystemsOptical Communication Systems - 922 Statistical MethodsStatistical Methods
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Joint content replication and request routing for social video distribution over cloud CDN: A community clustering method
Hu, Han1; Wen, Yonggang1; Chua, Tat-Seng2; Huang, Jian3; Zhu, Wenwu4; Li, Xuelong5 Source: IEEE Transactions on Circuits and Systems for Video Technology, v 26, n 7, p 1320-1333, July 2016
; ISSN: 10518215; DOI: 10.1109/TCSVT.2015.2455712; Article number: 7155559;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 School of Computer Engineering, Nanyang Technological University, Singapore; 639798, Singapore2 School of Computing, National University of Singapore, Singapore; 117417, Singapore3 Sun Yat-sen University, Guangzhou; 510275, China4 Tsinghua University, Beijing; 100084, China5 Center for OPTical IMagery Analysis and Learning, State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China
Abstract: The increasing popularity of online social networks (OSNs) has been transforming the dissemination pattern of social video contents. We can utilize the social information propagation pattern to improve the efficiency of social video distribution. In this paper, motivated by the social community classification, we present a social video replication and user request dispatching mechanism in the cloud content delivery network architecture to reduce the system operational cost, while guaranteeing the averaged service latency. Specifically, we first present a community classification method that clusters social users with social relationships, close geolocations, and similar video watching interests into various communities. Then, we conduct a large-scale measurement on a real OSN system to study the diversities of social video propagation and the effectiveness of our communities on smoothing the diversity. Finally, we propose the community-based video replication and request dispatching strategy and formulate it as a constrained optimization problem. Based on a stochastic optimization framework, we derive an online solution and rigorously prove the optimality. We evaluate our algorithm on a real trace under realistic settings and demonstrate that our algorithm can reduce the monetary cost by 30% against traditional approaches with the same service latency. © 2015 IEEE. (49 refs.)Main Heading: OptimizationControlled terms: Cluster analysis - Constrained optimization - Cost reduction - Information dissemination - Network architecture - Online systems - Social aspects - Social networking (online)Uncontrolled terms: Community detection - Constrained optimi-zation problems - Content delivery network - Large-scale measurement - Online social networks (OSNs) - Social videos - Stochastic optimizations - Traditional approachesClassification Code: 722.4 Digital Computers and SystemsDigital Computers and Systems - 723 Computer Software, Data Handling and ApplicationsComputer Software, Data Handling and Applications - 901.4 Impact of Technology on SocietyImpact of Technology on Society - 903.2 Information DisseminationInformation Dissemination - 921.5 Optimization TechniquesOptimization Techniques - 961 Systems ScienceSystems Science
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Low-penalty up to 16-QAM wavelength conversion in a low loss CMOS compatible spiral waveguide
Da Ros, Francesco1; Porto Da Silva, Edson1; Zibar, Darko1; Chu, Sai T.2; Little, Brent E.3; Morandotti, Roberto4; Galili, Michael1; Moss, David J.5; Oxenlewe, Leif K.1 Source: 2016 Optical Fiber Communications Conference and Exhibition, OFC 2016, August 9, 2016, 2016 Optical Fiber Communications Conference and Exhibition, OFC 2016; ISBN-13: 9781943580071; Article number: 7537565; Conference: 2016 Optical Fiber Communications Conference and Exhibition, OFC 2016, March 20, 2016 - March 24, 2016;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 DTU Fotonik, Technical University of Denmark, DTU, Kongens Lyngby; 2800, Denmark2 Department of Physics and Materials Science, City University of Hong Kong, Hong Kong3 Xi'An Institute of Optics and Precision Mechanics, CAS, Xi'an, China4 INSR - Énergie, Matériaux et Télécommunications, 1650 Blvd Lionel Boulet, Varennes; QC; J3X1S2, Canada5 School of Electrical and Computer Engineering, RMIT University, Melbourne; VIC; 3001, Australia
Abstract: Wavelength conversion of 32-Gbaud QPSK and 10-Gbaud 16-QAM is demonstrated using a 50-cm long low loss spiral Hydex-glass waveguide. BER < HD-FEC threshold is achieved over 10 nm bandwidth with OSNR penalty < 0.5 dB. © 2016 OSA. (17 refs.)Main Heading: Optical fiber communicationControlled terms: CMOS integrated circuits - Optical fibers - WaveguidesUncontrolled terms: CMOS Compatible - Glass waveguides - Low-loss - Spiral waveguidesClassification Code: 714.2 Semiconductor Devices and Integrated CircuitsSemiconductor Devices and Integrated Circuits - 714.3 WaveguidesWaveguides - 717.1 Optical Communication SystemsOptical Communication Systems - 741.1.2 Fiber OpticsFiber Optics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Deep object tracking with multi-modal data
Zhang, Xuezhi1, 2; Yuan, Yuan1; Lu, Xiaoqiang1 Source: IEEE CITS 2016 - 2016 International Conference on Computer, Information and Telecommunication Systems, August 16, 2016, IEEE CITS 2016 - 2016 International Conference on Computer, Information and Telecommunication Systems; ISBN-13: 9781509034406; DOI: 10.1109/CITS.2016.7546403; Article number: 7546403; Conference: 2016 International Conference on Computer, Information and Telecommunication Systems, CITS 2016, July 6, 2016 - July 8, 2016; Sponsor: State Key Laboratory of Integrated Services Networks (ISN); Xidian University; Yunnan Minzu University;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 Center for OPTical IMagery Analysis and Learning (OPTIMAL), Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, Shaanxi; 710119, China2 University of the Chinese Academy of Sciences, 19A Yuquanlu, Beijing; 100049, China
Abstract: Object tracking is a challenging topic in the field of computer vision since its performance is easily disturbed by occlusion, illumination change, background clutter, scale variation, etc. In this paper, we introduce a robust tracking algorithm that fuses information from both visible images and infrared (IR) images. The proposed tracking algorithm not only incorporates convolutional feature maps from the visible channel, but also employs a scale pyramid representation from IR channel. We estimate the target location by fusing multilayer convolutional feature maps, and predict the target scale from a scale pyramid. The pipeline of the proposed method is as follows. First, the hierarchical convolutional feature maps are obtained from visible images using VGG-Nets. Then, the accurate target location is predicted by the maximum response of correlation filters with the visible image feature maps. Finally, we obtain the precise object scale with a scale pyramid from infrared images where the difference between the target and the background is clear. In order to verify the performance of the proposed method, we capture six video sequences under different conditions. These sequences contain both visible channel and IR channel. Ten state-of-the-art tracking algorithms are compared with our method, and the experimental results show the effectiveness of the proposed tracker. © 2016 IEEE. (22 refs.)Main Heading: Tracking (position)Controlled terms: Computer vision - Convolution - Image processing - Infrared imaging - Modal analysisUncontrolled terms: Background clutter - Correlation filters - Illumination changes - Multi-modal data - Robust tracking - State of the art - Tracking algorithm - Visible channelsClassification Code: 716.1 Information Theory and Signal ProcessingInformation Theory and Signal Processing - 723.5 Computer ApplicationsComputer Applications - 746 Imaging TechniquesImaging Techniques - 921 MathematicsMathematics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Pressurization actuation based variable curvature mirror having variable thickness
Zhao, Hui1; Xie, Xiao-Peng1, 2; Xu, Liang1; Ding, Jiao-Teng1; Liu, Mei-Ying1; Fan, Xue-Wu1 Source: Guangzi Xuebao/Acta Photonica Sinica, v 45, n 11, November 1, 2016; Language: Chinese
; ISSN: 10044213; DOI: 10.3788/gzxb20164511.1122001; Article number: 1122001;
Publisher: Chinese Optical SocietyAuthor affiliation: 1 Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Space Optics Lab, Xi'an; 710119, China2 University of Chinese Academy of Sciences, Beijing; 100039, China
Abstract: Based on the model of annular force based actuation, the reasons why it is hard for annular force based variable curvature mirror to obtain a large saggitus variation and maintain a high-accuracy surface figure simultaneously were analyzed. From the elasticity theory of thin plate, a physical model of variable curvature mirror in which pressurization actuation and variable thickness design are combined together was proposed. The theoretical analysis results show that, by making the mirror thickness be variable from the center to the periphery portion and adopting the pressurization actuation, the large saggitus variation can be obtained while the surface figure accuracy can be maintained and higher than the annular line load variable curvature mirror. A duralumin prototype mirror was designed, fabricated and tested. The surface figure accuracy of the mirror before curvature variation is superior to λ/50 (632.8 nm). When a pressure of about 0.032 MPa is imposed, the mirror can provide a saggitus variation exceeding 22 μm and at the same the corresponding surface figure accuracy is still superior to λ/20 (632.8 nm), which verifies the theoretical analysis about variable thickness mirror and proves that the design combination integrating pressurization actuation and variable mirror thickness is a promising technical way to construct an applicable variable curvature mirror. © 2016, Science Press. All right reserved. (17 refs.)Main Heading: MirrorsControlled terms: Elasticity - Optical design - Pressurization - Thickness controlUncontrolled terms: Curvature variation - Elasticity theory - Mirror thickness - Optical zooming - Surface figure accuracies - Thin plate - Variable curvature mirror - Variable thicknessClassification Code: 731.3 Specific Variables ControlSpecific Variables Control - 741.1 Light/OpticsLight/Optics - 741.3 Optical Devices and SystemsOptical Devices and Systems
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Thermally accelerated ageing test of 808nm high power diode laser arrays in CW mode
Nie, Zhiqiang1; Wu, Di2; Lu, Yao1; Wu, Dhai1; Wang, Shuna1; Zhang, Pu1; Xiong, Lingling1; Li, Xiaoning2; Shen, Zenan2 Source: 2016 17th International Conference on Electronic Packaging Technology, ICEPT 2016, p 111-115, October 4, 2016, 2016 17th International Conference on Electronic Packaging Technology, ICEPT 2016; ISBN-13: 9781509013968; DOI: 10.1109/ICEPT.2016.7583100; Article number: 7583100; Conference: 17th International Conference on Electronic Packaging Technology, ICEPT 2016, August 16, 2016 - August 19, 2016;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Shaanxi, China2 Focuslight Technologies Co. LTD, Xi'an, Shaanxi, China
Abstract: The reliability is the important performance of high power semiconductor laser. Thermally accelerated ageing test is an important technology of lifetime evaluation and reliability analysis. In this study, three groups of thermally accelerated ageing tests of conduction-cooled-packaged 60W 808nm high power diode laser arrays packaged by Indium solder at constant current have been carried out. Analysis of ageing data suggest the extrapolated lifetime under room temperature to value device reliability. We also analyze and discuss the degradation modes. This work can provide guidance for optimizing the chip and package structure, is helpful for improving performance and enhancing reliability of high power semiconductor lasers. © 2016 IEEE. (13 refs.)Main Heading: Semiconductor lasersControlled terms: Chip scale packages - Defects - Degradation - Electronics packaging - High power lasers - Laser beam welding - Power semiconductor diodes - Reliability - Reliability analysis - Semiconductor diodesUncontrolled terms: Accelerated ageing tests - Device reliability - High power - High power semiconductor laser - High-power diode laser arrays - Improving performance - Lifetime evaluation - Provide guidancesClassification Code: 714.2 Semiconductor Devices and Integrated CircuitsSemiconductor Devices and Integrated Circuits - 744 LasersLasers - 802.2 Chemical ReactionsChemical Reactions - 951 Materials ScienceMaterials Science
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


50 μj Femtosecond Laser System Based on Strictly All-Fiber CPA Structure
Li, Feng1, 2, 3; Yang, Zhi1; Zhao, Wei1, 3; Li, Qianglong1; Zhang, Xin1, 2; Yang, Xiaojun1; Zhang, Wei1; Wang, Yishan1, 3 Source: IEEE Photonics Journal, v 8, n 5, October 2016
; ISSN: 19430655; DOI: 10.1109/JPHOT.2016.2614600; Article number: 7588072;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China2 University of Chinese Academy of Sciences, Beijing; 100049, China3 Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan; 030006, China
Abstract: We demonstrate a strictly all-polarization maintaining, all-fiber chirped pulse amplification of ultrashort pulses. Pulses with the duration of 933 fs and energy as high as 50 μJ are achieved at 200 kHz repetition rate in a compact size. The variations of the spectra and pulse widths as functions of the amplified output power have also been presented. To our best knowledge, this is the highest energy extracted from the strictly all-fiber chirped pulse amplification system. The environmentally stable femtosecond laser source will find various applications in practice. © 2016 IEEE. (13 refs.)Main Heading: Ultrashort pulsesControlled terms: Chirp modulation - Fiber amplifiers - Fibers - Photonic crystal fibers - Pulse repetition rateUncontrolled terms: Chirped pulse amplification systems - Chirped pulse amplifications - Compact size - Femtosecond laser system - Output power - Polarization maintaining - Pulsewidths - Repetition rateClassification Code: 716 Telecommunication; Radar, Radio and TelevisionTelecommunication; Radar, Radio and Television - 744.1 Lasers, GeneralLasers, General - 744.4 Solid State LasersSolid State Lasers - 951 Materials ScienceMaterials Science
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Optical micro-manipulation based on spatial modulation of optical fields
Liang, Yansheng1; Yao, Baoli1; Lei, Ming1; Yan, Shaohui1; Yu, Xianghua1; Li, Manman1 Source: Guangxue Xuebao/Acta Optica Sinica, v 36, n 10, October 10, 2016; Language: Chinese
; ISSN: 02532239; DOI: 10.3788/AOS201636.1026003; Article number: 1026003;
Publisher: Chinese Optical SocietyAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; Shaanxi; 710119, China
Abstract: Optical tweezers has become a powerful tool for research in life science and colloidal physics since its invention due to its advantages of mechanical contact-free and high-precision manipulation of micro-sized particles. However, the conventional single-trap optical tweezers is limited in the increasing demands of research. In recent years, the technique of spatial modulation of optical fields, which modulates the amplitude, phase and polarization state of light, has extensively enhanced the function of optical micro-manipulation, and promoted the advance in laser micro/nano fabricaton, optical sorting and transportation of micro-particles, and colloidal particles studies. The advance in spatial modulation of optical fields to date and their applications in optical micro-manipulation is reviewed, including the holographic optical tweezers, special-mode optical beams manipulation, and vector beams manipulation. © 2016, Chinese Lasers Press. All right reserved. (91 refs.)Main Heading: Optical tweezersControlled terms: Holography - Light modulation - Micromanipulators - Modulation - ScreeningUncontrolled terms: Holographic optical tweezers - Optical field - Optical micromanipulation - Opticaltrapping - Special-mode beams - Vector beamsClassification Code: 741.1 Light/OpticsLight/Optics - 743 HolographyHolography - 744.9 Laser ApplicationsLaser Applications - 746 Imaging TechniquesImaging Techniques - 802.3 Chemical OperationsChemical Operations
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


The effect analysis of conic coefficient error based on data measured from Talysurf and simulation of Zernike coefficients
Kai, Jiang1; Liu, Kai1; Song, Chong1; Peng, Qiu1; Peng, Wang1; Li, Gang1 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 9684, 2016, 8th International Symposium on Advanced Optical Manufacturing and Testing Technology: Optical Test, Measurement Technology, and Equipment
; ISSN: 0277786X, E-ISSN: 1996756X; ISBN-13: 9781628419191; DOI: 10.1117/12.2242968; Article number: 96843C; Conference: 8th International Symposium on Advanced Optical Manufacturing and Testing Technology: Optical Test, Measurement Technology, and Equipment, AOMATT 2016, April 26, 2016 - April 29, 2016; Sponsor: Chinese Academy of Sciences, Institute of Optics and Electronics (IOE); The Chinese Optical Society (COS);
Publisher: SPIEAuthor affiliation: 1 Photoelectric Track and Measurement Technology Research Department, Xi'an Institute of Optics and Precision Mechanics, CAS, Shaanxi Xi'an; 710119, China
Abstract: Derivation of the conic coefficient error of practical aspheric optic surface is quite significant to aspheric machining accuracy, optical system imaging quality analysis and decomposition analysis of optical lenses. The primary mirror of R-c telescope system was tested by Taylor Hobson Talysurf. The practical surface was fitted using Zernike polynomials based on the date measured from Talysurf. Though taking the Zernike coefficients into the optical system, the effect of the aberration which was brought by optical machining to the optical system imaging quality was obtained. The analysis shows that the spherical aberration was brought into the optical system because of the figure error of the primary mirror. And the value of the spherical aberration was same to the practical alignment result. Then the conicoid aspherical degree of the primary mirror was tested by the Talysurf. The machining deviation of the conic coefficient was gotten though comparing the conicoid aspherical degree of the practical primary mirror with that of the perfect primary mirror. The practical conic coefficient was calculated by the deviation. Taking the practical conic coefficient into the R-c telescope system, the degradation of the optical system imaging quality was known. Also the spherical aberration was brought into the optical system. Experimental results show that the value of the spherical aberration analyzed by the two methods is same and consist with the practical alignment result. That is to say that the conic coefficient changed due to machining error of the conicoid aspherical degree. Because of the change the spherical aberration was attached to primary mirror. And which caused the optical system imaging quality declined. Finally, corrector was designed to balance the spherical aberration of the primary mirror. Ensure that the optical system imaging quality meet the requirement. © 2016 SPIE. (6 refs.)Main Heading: Optical systemsControlled terms: Aberrations - Aspherics - Errors - Lenses - Machining - Manufacture - Mirrors - Optical design - Optical testing - Quality control - Spheres - TelescopesUncontrolled terms: Conic Coefficient - Contourgraph - Decomposition analysis - Machining Accuracy - Spherical aberrations - Telescope system - Zernike coefficient - Zernike polynomialsClassification Code: 604.2 Machining OperationsMachining Operations - 741.1 Light/OpticsLight/Optics - 741.3 Optical Devices and SystemsOptical Devices and Systems - 913.3 Quality Assurance and ControlQuality Assurance and Control - 913.4 ManufacturingManufacturing
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Analysis on deployment error of segmented mirror optical system
Wang, Chenchen1, 2; Zou, Gangyi1, 2; Pang, Zhihai1; Li, Ruichang1, 2; Fan, Xuewu1 Source: Guangxue Xuebao/Acta Optica Sinica, v 36, n 11, November 10, 2016; Language: Chinese
; ISSN: 02532239; DOI: 10.3788/AOS201636.1122005; Article number: 1122005;
Publisher: Chinese Optical SocietyAuthor affiliation: 1 Space Optics Laboratory, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; Shaanxi; 710119, China2 University of Chinese Academy of Sciences, Beijing; 100049, China
Abstract: The main method to improve the resolution of optical system is enlarging the pupil of the optical system, and segmenting sub-mirrors to get an equivalent large diameter primary mirror is a common way to enlarge clear aperture. After the deployment of sub-mirrors for segmented mirrors optical system on orbit, there is deviation between deployment position and the designed position, which is called position error. The error determines the imaging quality of the optical system. So it is necessary to analyze the precision of the position of sub-mirrors. Optical software is used to model the segmented mirror optical system, and the relationship curves between position error and the system's imaging quality is got by adjusting position error of six degrees of freedom for sub-mirrors. The results show that root mean square (RMS) values generated by the same position error are different when sub-mirrors are at the different positions. The middle mirrors are sensitive to the movement along X axis direction, and the outer ones are sensitive to the movement along the Y axis direction. Two methods are used to distribute the errors into the sub-mirror position error. One is distributing the position error to each sub-mirror alone. Another is distributing the same position error to each sub-mirror. The results show that the former way has a more relax position error when the generated wavefront errors are the same. © 2016, Chinese Lasers Press. All right reserved. (21 refs.)Main Heading: Optical systemsControlled terms: Degrees of freedom (mechanics) - Errors - Mirrors - Optical design - WavefrontsUncontrolled terms: Optical software - Piston errors - Position errors - Root mean square values - Segmented mirror - Six degrees of freedom - Tilt errors - Wavefront errorsClassification Code: 741.1 Light/OpticsLight/Optics - 741.3 Optical Devices and SystemsOptical Devices and Systems - 931.1 MechanicsMechanics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


The impact of fabrication errors of double-layer BOE on diffraction efficiency
Ma, Zebin1, 2; Kang, Fuzeng1; Wang, Hao1, 2 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 9685, 2016, 8th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Design, Manufacturing, and Testing of Micro- and Nano-Optical Devices and Systems; and Smart Structures and Materials
; ISSN: 0277786X, E-ISSN: 1996756X; ISBN-13: 9781628419207; DOI: 10.1117/12.2242497; Article number: 96850H; Conference: 8th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Design, Manufacturing, and Testing of Micro- and Nano-Optical Devices and Systems; and Smart Structures and Materials, AOMATT 2016, April 26, 2016 - April 29, 2016; Sponsor: Chinese Academy of Sciences, Institute of Optics and Electronics (IOE); The Chinese Optical Society (COS);
Publisher: SPIEAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics of CAS, Xi'an, China2 University of Chinese Academy of Sciences, Beijing, China
Abstract: With the development of optical technology, optical instruments become smaller and more integrated. Because of the high diffraction efficiency and light weight, binary optical elements become more and more popular. Binary optical elements can only blaze at one wavelength, it has high diffraction efficiency at design wavelength. But the diffraction efficiency of binary optical elements will decrease quickly with the change of wavelength. And this situation will have a big impact on image quality. Since double-layer BOE can blaze at two wavelengths, it has high diffraction efficiency at wide spectral bandwidth. There are kinds of fabrication errors. Based on scalar diffraction theory, this paper analyzes the diffraction efficiency of double-layer BOE with fabrication errors and simulates it in MATLAB. Simulation shows the diffraction efficiency decreases quickly if the depth errors of two layers are opposite, and this situation should be avoided. As for periodic errors, tilt errors and angular errors, these fabrication errors have different impact of double-layer BOE on diffraction efficiency. © 2016 SPIE. (18 refs.)Main Heading: DiffractionControlled terms: Bins - Diffraction efficiency - Diffractive optical elements - Efficiency - Errors - Fabrication - Manufacture - Materials testing - MATLAB - Optical devices - Optical instrumentsUncontrolled terms: Binary optical element - Design wavelength - Double layers - Fabrication errors - Optical technology - Periodic errors - Scalar diffraction theory - Spectral bandwidthClassification Code: 694.4 StorageStorage - 741.3 Optical Devices and SystemsOptical Devices and Systems - 913.1 Production EngineeringProduction Engineering - 913.4 ManufacturingManufacturing - 921 MathematicsMathematics - 941.3 Optical InstrumentsOptical Instruments - 951 Materials ScienceMaterials Science
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Self-deployable structure designed for space telescope for microsatellite application
Zhao, Chao1; Li, Chuang2; Zhou, Nan2; Liao, Hongqiang1 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 9685, 2016, 8th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Design, Manufacturing, and Testing of Micro- and Nano-Optical Devices and Systems; and Smart Structures and Materials
; ISSN: 0277786X, E-ISSN: 1996756X; ISBN-13: 9781628419207; DOI: 10.1117/12.2242957; Article number: 96850B; Conference: 8th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Design, Manufacturing, and Testing of Micro- and Nano-Optical Devices and Systems; and Smart Structures and Materials, AOMATT 2016, April 26, 2016 - April 29, 2016; Sponsor: Chinese Academy of Sciences, Institute of Optics and Electronics (IOE); The Chinese Optical Society (COS);
Publisher: SPIEAuthor affiliation: 1 Institute of Systems Engineering, China Academy of Engineering Physics, Mianyang; 621000, China2 Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China
Abstract: With the gradual development of micro-satellite technology and the extension of application field of earth observation technology, researchers show more concern and attention on how to obtain high-resolution images with microsatellite platform equipped with space telescope. Such microsatellites require the space telescopes with small volume, low mass, and low cost. Deployable telescope is a good choice to meet these requirements, and it has the same capabilities as the traditional space telescope. We investigate a space telescope with smart self-deployable structure. The telescope is folded before launch, the distance between primary mirror and secondary mirror becomes short and the volume of the telescope becomes small, and the telescope extends to its working configuration after it is in orbit. The deployable structure is one of the key techniques of deployable space telescope, and this paper focuses on the design of a self-deployable structure of the secondary mirror. There are mainly three parts in this paper. Firstly, the optics of the telescope is presented, and a Ritchey-Chretien (RC) type optical system is designed. Secondly, the self-deployable structure is designed and the finite element method (FEM) is used to analyze dynamics of the extended telescope. Thirdly, an adjusting mechanism with six degrees of freedom to correct the misalignment of the secondary mirror is investigated, and the kinematics is discussed. © 2016 SPIE. (9 refs.)Main Heading: Earth (planet)Controlled terms: Degrees of freedom (mechanics) - DNA sequences - Finite element method - Manufacture - Materials testing - Mirrors - Optical devices - Optical systems - Orbits - Space telescopesUncontrolled terms: Deployable structure - Deployable telescopes - Earth Observation Technology - High resolution image - Micro satellite - Micro-satellite platforms - Self-deployable - Six degrees of freedomClassification Code: 461.2 Biological Materials and Tissue EngineeringBiological Materials and Tissue Engineering - 537.1 Heat Treatment ProcessesHeat Treatment Processes - 741.3 Optical Devices and SystemsOptical Devices and Systems - 921.6 Numerical MethodsNumerical Methods - 931.1 MechanicsMechanics - 951 Materials ScienceMaterials Science
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Temporal Hilbert transform based on an integrated frequency comb source
Shoeiby, Mehrdad1; Nguyen, Thach G.1; Schroeder, Jochen1; Chu, Sai T.2; Little, Brent E.3; Morandotti, Roberto4; Mitchell, Arnan1, 5; Moss, David J.6 Source: 2016 Conference on Lasers and Electro-Optics, CLEO 2016, December 16, 2016, 2016 Conference on Lasers and Electro-Optics, CLEO 2016; ISBN-13: 9781943580118; Article number: 7788419; Conference: 2016 Conference on Lasers and Electro-Optics, CLEO 2016, June 5, 2016 - June 10, 2016;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 Electrical and Computer Engineering, School of Engineering, RMIT University, Melbourne; VIC; 3001, Australia2 Department of Physics and Materials Science, City University of Hong Kong, Hong Kong3 Xi'An Institute of Optics and Precision Mechanics, CAS, Xi'an, China4 INSR-Énergie, Matériaux et Télécommunications, 1650 Blvd Lionel Boulet, Varennes; QC; J3X1S2, Canada5 ARC Centre of Excellence for Ultrahigh Bandwidth Devices for Optical Systems (CUDOS), Australia6 Centre for MicroPhotonics, Swinburne University of Technology, Hawthorne; VIC; 3122, Australia
Abstract: An experimentally demonstrated temporal Hilbert transformer based on an integrated optical frequency comb source is exploited to obtain the temporal Hilbert transform of a Gaussian pulse with a full-width half maximum duration of 0.12ns. © 2016 OSA. (6 refs.)
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Modeling the encoding structure and spatial resolution of photon counting imagers with Vernier anode readout
Yang, Hao1; Zhao, Baosheng2; Yan, Qiurong3; Liu, Yong'an2 Source: Chinese Optics Letters, v 14, n 12, December 10, 2016
; ISSN: 16717694; DOI: 10.3788/COL201614.121102; Article number: 121102;
Publisher: Science PressAuthor affiliation: 1 Shaanxi Key Laboratory of Optical Information Technology, School of Science, Northwestern Polytechnical University, Xi'an; 710072, China2 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China3 Department of Electronic Information Engineering, Nanchang University, Nanchang; 330031, China
Abstract: We present the spatial resolution estimation methods for a photon counting system with a Vernier anode. A limiting resolution model is provided according to discussions of surface encoding structure and quantized noise. The limiting resolution of a Vernier anode is revealed to be significantly higher than that of a microchannel plate. The relationship between the actual spatial resolution and equivalent noise charge of a detector is established by noise analysis and photon position reconstruction. The theoretical results are demonstrated to be in good agreement with the experimental results for a 1.2 mm pitch Vernier anode. © 2016 Chinese Optics Letters. (20 refs.)Main Heading: AnodesControlled terms: Electrodes - Encoding (symbols) - Image resolution - PhotonsUncontrolled terms: Encoding structure - Equivalent noise charges - Micro channel plate - Photon counting - Photon counting system - Position reconstruction - Resolution modeling - Spatial resolutionClassification Code: 714.1 Electron TubesElectron Tubes - 723.2 Data Processing and Image ProcessingData Processing and Image Processing - 931.3 Atomic and Molecular PhysicsAtomic and Molecular Physics
Database: Compendex
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A method for extracting urban built-up area based on RS indexes
Qin, Ruijiao1, 2; Li, Jiansong3; Tang, Huijun1 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 10156, 2016, Hyperspectral Remote Sensing Applications and Environmental Monitoring and Safety Testing Technology
; ISSN: 0277786X, E-ISSN: 1996756X; ISBN-13: 9781510607705; DOI: 10.1117/12.2247393; Article number: 101561V; Conference: International Symposium on Hyperspectral Remote Sensing Applications and the International Symposium on Environmental Monitoring and Safety Testing Technology, May 9, 2016 - May 11, 2016; Sponsor: China High-Tech Industrialization Association (CHIA); Chinese Society for Optical Engineering (CSOE);
Publisher: SPIEAuthor affiliation: 1 Xi'an Institute of Optics and Precision Mechanics of CAS, Xi'an, Shaanxi; 710068, China2 University of Chinese Academy of Sciences, Beijing; 100049, China3 School of Informatics Engineering for Remote Sensing, Wuhan University, Wuhan; 430079, China
Abstract: Within administrative regions, urban built-up areas are vast stretches of constructed areas equipped with basic public facilit ies. Human act ivit ies most frequently take place within urban regions and the dynamic evolution of urbanization has caused profound variations in urban spatial structures. Conventional boundary extraction methods are complicated and require human intervention. This article innovatively proposes a vector method that combines a data-dimension compression index known as an Index-based Built-up Index (IBI) with aggregate analysis to extract vector boundaries of urban built-up areas automatically by setting a threshold value and the parameters for aggregate analysis. Datadimension compression technology is used to extract urban built-up areas using thematic bands (rather than original bands) to build indexes, which improves the precision of extraction. Areas ext racted by the methods above contains urban built-up areas, rural built-up areas, independent houses and fully bare areas. Aggregate analysis aggregates a certain range of non-Adjacent plots into a new polygon section. This method has made it easy to analyze the spatial expansion of Wuhan city from 2003 to 2013. This method avoids cumbersome process es of outlining vector boundaries by artificial visual interpretation with a better working efficiency and reduced costs than other methods, which cannot accurately determine vector boundaries to an accurate degree by manual vector quantizat ion without depending on other data or expert knowledge. Compared with t raditional boundary extraction methods, this vector method is more efficient, precise, objective, and exquisite. © 2016 SPIE. (20 refs.)Main Heading: Safety testingControlled terms: Aggregates - Data compression - Environmental engineering - Environmental technology - Extraction - Remote sensing - VectorsUncontrolled terms: Boundary extraction - Built-up areas - ETM+ image - Evolution analysis - RS indexesClassification Code: 406 Highway EngineeringHighway Engineering - 454 Environmental EngineeringEnvironmental Engineering - 802.3 Chemical OperationsChemical Operations - 914.1 Accidents and Accident PreventionAccidents and Accident Prevention - 921.1 AlgebraAlgebra
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Annular-force-based variable curvature mirror combined with multi-point actuation array to improve the surface figure accuracy: A prototype design
Zhao, Hui1; Xie, Xiaopeng2; Ren, Guorui1; Du, Yunfei1; Liu, Meiying1; Wei, Jingxuan3 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 9683, 2016, 8th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Advanced Optical Manufacturing Technologies
; ISSN: 0277786X, E-ISSN: 1996756X; ISBN-13: 9781628419184; DOI: 10.1117/12.2242256; Article number: 96831V; Conference: 8th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Advanced Optical Manufacturing Technologies, AOMATT 2016, April 26, 2016 - April 29, 2016; Sponsor: Chinese Academy of Sciences, Institute of Optics and Electronics (IOE); The Chinese Optical Society (COS);
Publisher: SPIEAuthor affiliation: 1 Xi'an Institute of Optics and Precision Mechanics of CAS, Xi'an; 710119, China2 Graduate School of University of Chinese Academy of Sciences, Beijing; 100049, China3 School of Computer Science and Technology, Xidian University, Xi'an; 710071, China
Abstract: In recent years, a novel optical zooming technique has been paid much attention. With the help of optical leveraging effect, it is possible to alter the system focal length dramatically without moving elements involved in by only changing the curvature radius of VCM (variable curvature mirror) slightly. With no doubt, VCM is the key to realize non-moving element optical zooming and it has to provide large enough saggitus variation while still maintaining the high surface figure accuracy to ensure high quality imaging. In our previously published paper, an annular force based VCM has been designed, fabricated and tested. Experiments demonstrate that with the aperture of 100mm and thickness of 2mm, the VCM could generate a large saggitus variation exceeding 30 (=632.8nm). However, the optical quality degrades very fast and this makes such a VCM unsuitable for optical imaging in visible band. Therefore in this manuscript, a multipoint actuation array, which is composed of totally 49 piezoelectric actuators, is embedded into the annular structure to aim to correct the surface figure distortion caused by large saggitus variation. The new structure model has been designed and numerical simulation indicates that the surface figure distortion could be well corrected as long as the degraded surface figure accuracy is better than 1.8 (=632.8nm) (RMS). Based on this, a new prototype VCM is being fabricated and intermediate results are reported here. © 2016 SPIE. (14 refs.)Main Heading: Piezoelectric actuatorsControlled terms: Boundary integral equations - Manufacture - Mirrors - PiezoelectricityUncontrolled terms: High-quality imaging - Intermediate results - Optical qualities - Piezoelectric actuation - Saggitus variation - Structure modeling - Surface figure accuracies - Variable curvature mirrorClassification Code: 537.1 Heat Treatment ProcessesHeat Treatment Processes - 701.1 Electricity: Basic Concepts and PhenomenaElectricity: Basic Concepts and Phenomena - 732 Control DevicesControl Devices - 741.3 Optical Devices and SystemsOptical Devices and Systems - 921.2 CalculusCalculus
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


On-chip frequency comb of entangled qubits
Kues, Michael1; Reimer, Christian1; Roztocki, Piotr1; Wetzel, Benjamin1, 2; Grazioso, Fabio1; Bromberg, Yaron3; Little, Brent E.4; Chu, Sai T.5; Moss, David J.6; Caspani, Lucia1, 7; Morandotti, Roberto1 Source: Optics InfoBase Conference Papers, August 15, 2016, Latin America Optics and Photonics Conference, LAOP 2016; ISBN-13: 9781943580163; DOI: 10.1364/LAOP.2016.LTu2D.4.pdf; Conference: Latin America Optics and Photonics Conference, LAOP 2016, August 22, 2016 - August 26, 2016; Sponsor: Centro de Investigaciones en Optica, A.C.; CONACYT; INAOE; SEP; Universidad de Guanajuata;
Publisher: OSA - The Optical SocietyAuthor affiliation: 1 INRS-EMT, 1650 Boulevard Lionel-Boulet, Varennes; QC; J3X 1S2, Canada2 Department of Physics and Astronomy, University of Sussex, Falmer, Brighton; BN1 9RH, United Kingdom3 Department of Applied Physics, Yale University, New Haven; CT; 06520, United States4 Xi'an Institute of Optics and Precision Mechanics of CAS, Xi'an, China5 Department of Physics and Material Science, City University of Hong Kong, Tat Chee Avenue, Hong Kong6 Centre for Micro Photonics, Swinburne University of Technology, Hawthorne; VIC; 3122, Australia7 School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh; EH14 4AS, United Kingdom
Abstract: We show the generation of multiple time-bin entangled qubits, with high purity and covering the entire L, C, and S telecommunication bands. This is achieved using spontaneous four-wave mixing within an on-chip micro-resonator. © OSA 2016. (13 refs.)Main Heading: Quantum entanglementControlled terms: Four wave mixing - Microelectromechanical devices - Photonics - Quantum computers - ResonatorsUncontrolled terms: Entangled qubits - High purity - Micro resonators - On chips - Spontaneous four-wave mixing - Telecommunication bandsClassification Code: 722 Computer Systems and EquipmentComputer Systems and Equipment - 741.1 Light/OpticsLight/Optics - 931.4 Quantum Theory; Quantum MechanicsQuantum Theory; Quantum Mechanics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


High-energy Q-switched Yb-doped fiber laser based on WS2 film saturable absorber
Wang, Junli1; Li, Sha1; Wang, Yonggang3; Zhu, Jiangfeng1; Wei, Zhiyi2 Source: Asia Communications and Photonics Conference, ACP, 2016, Proceedings - Asia Communications and Photonics Conference 2016, ACP 2016
; ISSN: 2162108X; DOI: 10.1364/ACPC.2016.AF4I.1; Conference: 2016 Asia Communications and Photonics Conference, ACP 2016, November 2, 2016 - November 5, 2016;
Publisher: OSA - The Optical SocietyAuthor affiliation: 1 School of Physics and Optoelectronic Engineering, Xidian University, Xi'an; 710071, China2 Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing; 100190, China3 State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China
Abstract: An all-fiber high-energy Q-switched Yb-doped fiber laser using WS2 film as the saturable absorber (SA) is demonstrated. The highest single pulse energy of 56.50 nJ and the shortest pulse width of 1.0 μs were achieved. © OSA 2016. (11 refs.)Main Heading: Saturable absorbersControlled terms: Fiber lasers - Photonics - Q switching - YtterbiumUncontrolled terms: All fiber - Pulsewidths - Q-switched - Single pulse energy - Yb doped fiber laserClassification Code: 547.2 Rare Earth MetalsRare Earth Metals - 741.1 Light/OpticsLight/Optics - 744 LasersLasers
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


A non-negative low-rank representation for hyperspectral band selection
Feng, Yachuang1, 2; Yuan, Yuan1; Lu, Xiaoqiang1 Source: International Journal of Remote Sensing, v 37, n 19, p 4590-4609, October 1, 2016
; ISSN: 01431161, E-ISSN: 13665901; DOI: 10.1080/01431161.2016.1214299;
Publisher: Taylor and Francis Ltd.Author affiliation: 1 Center for OPTical IMagery Analysis and Learning (OPTIMAL), State Key Laboratory of Transient Optics and Photonics, Xi’an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi’an, China2 University of the Chinese Academy of Sciences, Beijing, China
Abstract: Hyperspectral images are widely used in real applications due to their rich spectral information. However, the large volume brings a lot of inconvenience, such as storage and transmission. Hyperspectral band selection is an important technique to cope with this issue by selecting a few spectral bands to replace the original image. This article proposes a novel band selection algorithm that first estimates the redundancy through analysing relationships among spectral bands. After that, spectral bands are ranked according to their relative importance. Subsequently, in order to remove redundant spectral bands and preserve the original information, a maximal linearly independent subset is constructed as the optimal band combination. Contributions of this article are listed as follows: (1) A new strategy for band selection is proposed to preserve the original information mostly; (2) A non-negative low-rank representation algorithm is developed to discover intrinsic relationships among spectral bands; (3) A smart strategy is put forward to adaptively determine the optimal combination of spectral bands. To verify the effectiveness, experiments have been conducted on both hyperspectral unmixing and classification. For unmixing, the proposed algorithm decreases the average root mean square errors (RMSEs) by 0.05, 0.03, and 0.05 for the Urban, Cuprite, and Indian Pines data sets, respectively. With regard to classification, our algorithm achieves the overall accuracies of 77.07% and 89.19% for the Indian Pines and Pavia University data sets, respectively. These results are close to the performance with original images. Thus, comparative experiments not only illustrate the superiority of the proposed algorithm, but also prove the validity of band selection on hyperspectral image processing. © 2016 Informa UK Limited, trading as Taylor & Francis Group. (52 refs.)Controlled terms: algorithm - comparative study - data set - error analysis - image analysis - image classification - spectral analysisClassification Code: 71.8.5.4 Remote sensing: numerical and image analysisRemote sensing: numerical and image analysis
Database: GEOBASE
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Ultrafast interrogation of fully distributed chirped fibre Bragg grating strain sensor
Ahmad, Eamonn J1; Wang, Chao1; Feng, Dejun1, 2; Yan, Zhijun3, 4; Zhang, Lin3 Source: 2016 IEEE Photonics Conference, IPC 2016, p 482-483, January 23, 2017, 2016 IEEE Photonics Conference, IPC 2016; ISBN-13: 9781509019069; DOI: 10.1109/IPCon.2016.7831190; Article number: 7831190; Conference: 29th IEEE Photonics Conference, IPC 2016, October 2, 2016 - October 6, 2016;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 School of Engineering and Digital Arts, University of Kent, Canterbury; CT2 7NT, United Kingdom2 School of Information Science and Engineering, Shandong University, Jinan; 250100, China3 Aston Institute of Photonic Technologies, Aston University, Birmingham; B4 7ET, United Kingdom4 State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China
Abstract: A novel ultrafast and high spatial-resolution interrogation method for fully distributed chirped fibre Bragg grating sensors based on photonic time-stretch frequency-domain reflectometry is presented. Real-Time interrogation at measurement speed of 50 MHz with a spatial resolution of 35 μm was experimentally demonstrated. © 2016 IEEE. (5 refs.)Main Heading: PhotonicsControlled terms: Bragg gratings - Fiber Bragg gratings - Frequency domain analysis - Image resolutionUncontrolled terms: Chirped fibre Bragg gratings - Frequency domain reflectometry - High spatial resolution - Measurement speed - Photonic time-stretch - Spatial resolution - Strain sensors - Ultra-fastClassification Code: 741.3 Optical Devices and SystemsOptical Devices and Systems - 921.3 Mathematical TransformationsMathematical Transformations
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Shape-Constrained Sparse and Low-Rank Decomposition for Auroral Substorm Detection
Yang, Xi1; Gao, Xinbo1; Tao, Dacheng2; Li, Xuelong3; Han, Bing4; Li, Jie4 Source: IEEE Transactions on Neural Networks and Learning Systems, v 27, n 1, p 32-46, January 2016
; ISSN: 2162237X, E-ISSN: 21622388; DOI: 10.1109/TNNLS.2015.2411613; Article number: 7070710;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 State Key Laboratory of Integrated Services Networks, School of Electronic Engineering, Xidian University, Xi'an, China2 Centre for Quantum Computation and Intelligent Systems, Faculty of Engineering and Information Technology, University of Technology, Sydney, 81 Broadway Street, Ultimo; NSW, Australia3 Center for OPTical IMagery Analysis and Learning (OPTIMAL), State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, China4 Video and Image Processing System Laboratory, School of Electronic Engineering, Xidian University, Xi'an, China
Abstract: An auroral substorm is an important geophysical phenomenon that reflects the interaction between the solar wind and the Earth's magnetosphere. Detecting substorms is of practical significance in order to prevent disruption to communication and global positioning systems. However, existing detection methods can be inaccurate or require time-consuming manual analysis and are therefore impractical for large-scale data sets. In this paper, we propose an automatic auroral substorm detection method based on a shape-constrained sparse and low-rank decomposition (SCSLD) framework. Our method automatically detects real substorm onsets in large-scale aurora sequences, which overcomes the limitations of manual detection. To reduce noise interference inherent in current SLD methods, we introduce a shape constraint to force the noise to be assigned to the low-rank part (stationary background), thus ensuring the accuracy of the sparse part (moving object) and improving the performance. Experiments conducted on aurora sequences in solar cycle 23 (1996-2008) show that the proposed SCSLD method achieves good performance for motion analysis of aurora sequences. Moreover, the obtained results are highly consistent with manual analysis, suggesting that the proposed automatic method is useful and effective in practice. © 2015 IEEE. (66 refs.)Main Heading: Interference suppressionControlled terms: Magnetosphere - Solar energyUncontrolled terms: Automatic method - Detection methods - Earth's magnetosphere - Geophysical phenomena - Large scale data sets - Noise interference - Shape constraints - Sparse and low ranks
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Spatiochromatic Context Modeling for Color Saliency Analysis
Zhang, Jun1; Wang, Meng1; Zhang, Shengping2; Li, Xuelong3; Wu, Xindong1, 4 Source: IEEE Transactions on Neural Networks and Learning Systems, v 27, n 6, p 1177-1189, June 2016
; ISSN: 2162237X, E-ISSN: 21622388; DOI: 10.1109/TNNLS.2015.2464316; Article number: 7222459;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 School of Computer Science and Information Engineering, Hefei University of Technology, Hefei; 230009, China2 School of Computer Science and Technology, Harbin Institute of Technology, Weihai; 264209, China3 State Key Laboratory of Transient Optics and Photonics, Center for Optical Imagery Analysis and Learning, Xi'An Institute of Optics and Precision Mechanics, Xi'an; 710119, China4 Department of Computer Science, University of Vermont, Burlington; VT; 05405, United States
Abstract: Visual saliency is one of the most noteworthy perceptual abilities of human vision. Recent progress in cognitive psychology suggests that: 1) visual saliency analysis is mainly completed by the bottom-up mechanism consisting of feedforward low-level processing in primary visual cortex (area V1) and 2) color interacts with spatial cues and is influenced by the neighborhood context, and thus it plays an important role in a visual saliency analysis. From a computational perspective, the most existing saliency modeling approaches exploit multiple independent visual cues, irrespective of their interactions (or are not computed explicitly), and ignore contextual influences induced by neighboring colors. In addition, the use of color is often underestimated in the visual saliency analysis. In this paper, we propose a simple yet effective color saliency model that considers color as the only visual cue and mimics the color processing in V1. Our approach uses region-/boundary-defined color features with spatiochromatic filtering by considering local color-orientation interactions, therefore captures homogeneous color elements, subtle textures within the object and the overall salient object from the color image. To account for color contextual influences, we present a divisive normalization method for chromatic stimuli through the pooling of contrary/complementary color units. We further define a color perceptual metric over the entire scene to produce saliency maps for color regions and color boundaries individually. These maps are finally globally integrated into a one single saliency map. The final saliency map is produced by Gaussian blurring for robustness. We evaluate the proposed method on both synthetic stimuli and several benchmark saliency data sets from the visual saliency analysis to salient object detection. The experimental results demonstrate that the use of color as a unique visual cue achieves competitive results on par with or better than 12 state-of-the-art approaches. © 2015 IEEE. (87 refs.)Main Heading: ColorControlled terms: Image segmentation - Object recognition - VisualizationUncontrolled terms: Chromatic stimuli - Cognitive psychology - Normalization methods - Orientation interaction - Perceptual metrics - Primary visual cortex - Salient object detection - State-of-the-art approach
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Effects of Laser Repetition Rate and Fluence on Micromachining of TiC Ceramic
Zhang, Ying1; Wang, Yuqian1; Zhang, Junzhan1; Liu, Yongsheng2; Yang, Xiaojun3; Li, Weinan3 Source: Materials and Manufacturing Processes, v 31, n 7, p 832-837, May 18, 2016
; ISSN: 10426914, E-ISSN: 15322475; DOI: 10.1080/10426914.2015.1037916;
Publisher: Taylor and Francis Inc.Author affiliation: 1 College of Materials and Mineral Resources, Xi'an University of Architecture and Technology, Xi'an, Shaanxi, China2 Science and Technology on Thermostructure Composite Materials Laboratory, Northwestern Polytechnical University, Xi'an, Shaanxi, China3 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, Shaanxi, China
Abstract: Micromachining of titanium carbide (TiC) ceramic is very difficult because of its high hardness and brittleness. Femtosecond pulsed laser was employed to process circular rings on the surface of TiC ceramic. The interaction area between femtosecond laser pulses and TiC at different laser repetition rates and fluences was studied. Morphology and composition of irradiated area were analyzed by scanning electron microscope, energy dispersive spectroscopy, and Raman spectrum. The results indicated that the radius of outer circle was close to the intended radius. Laser fluence had obvious effects on the radius and width of circular rings, compared to laser repetition rate. The width of circular rings increased rapidly with increasing laser fluence from 2.55 × 10-2to 1.27 × 10-1J/mm2, and then stabilized at around 40 μm when laser fluence was above 7.64 × 10-1J/mm2. The surface of circular rings was characterized by ripples at the lower laser fluence. With increasing laser fluence, four kinds of typical morphology were observed, including ripples, cauliflower-like particles, ball-like particles, and deposited oxide layer. Ball-like particles contained high concentration of titanium, which came from melt ball splashing from ablation area. The others came from the different oxidation stages occurred on the surface of TiC sample. © Copyright 2016 Taylor & Francis Group, LLC. (22 refs.)Main Heading: Pulsed lasersControlled terms: Ceramic materials - Chemical analysis - Composite micromechanics - Energy dispersive spectroscopy - Fracture mechanics - Laser pulses - Lasers - Micromachining - Morphology - Pulse repetition rate - Scanning electron microscopy - Titanium - Titanium carbide - Ultrafast lasers - Ultrashort pulsesUncontrolled terms: Femtosecond pulsed laser - Femtoseconds - Fluences - Laser repetition rate - Morphology and composition - Repetition rate - TiC - Titanium carbides (TiC)
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Hydrothermal synthesis of MoS2nanosheets films: Microstructure and formation mechanism research
Miao, Hui1, 2; Hu, Xiaoyun1, 2; Sun, Qian1; Hao, Yuanyuan1; Wu, Hao1; Zhang, Dekai1, 2; Bai, Jintao1, 2; Liu, Enzhou3; Fan, Jun3; Hou, Xun1, 2, 4 Source: Materials Letters, v 166, p 121-124, March 1, 2016
; ISSN: 0167577X, E-ISSN: 18734979; DOI: 10.1016/j.matlet.2015.12.010;
Publisher: ElsevierAuthor affiliation: 1 School of Physics, Northwest University, Xi'an, China2 Natl. Photoelectric Technol. and Funct. Mat. and Applic. of Sci. and Technol. Intl. Cooperation Base, Northwest University, Xi'an, China3 School of Chemical Engineering, Northwest University, Xi'an, China4 State Key Laboratory of Transient Optics and Technology, Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, China
Abstract: MoS2nanosheets films were successfully prepared by Ti foil assisted hydrothermal synthesis method (labeled as Ti-MoS2nanosheets films). The downside and upside of the films showed different novel morphologies with nanosheets arranged regularly and flowerlike microspheres, respectively. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscope (TEM). X-ray diffraction patterns showed that the peaks along (002) planes made a wide shift from 14.2° to 9.4° compared to its standard position located at 14.2° at the beginning of the hydrothermal process, then gradually returned back to its normal position with the hydrothermal treatment time going on. However, time was not the only element to influence the position of the main diffraction peaks, a relatively low hydrothermal treatment temperature could also lead to the diffraction peaks' shift. In addition, TEM images indicated that the nanosheets film with hydrothermal treatment time for 24 h had a good single-crystal structure. Otherwise, the formation mechanism was carefully discussed and a possible formation mechanism was proposed. © 2015 Elsevier B.V. (6 refs.)Main Heading: Hydrothermal synthesisControlled terms: Crystal growth - Crystal microstructure - Crystal structure - Microstructure - Molybdenum compounds - Nanosheets - Scanning electron microscopy - Single crystals - Synthesis (chemical) - Thin films - Transmission electron microscopy - X ray diffractionUncontrolled terms: Diffraction peaks - Flower-like microspheres - Formation mechanism - Hydrothermal process - Hydrothermal treatments - Its standards - Novel morphologies - TEM imagesClassification Code: 761 NanotechnologyNanotechnology - 802.2 Chemical ReactionsChemical Reactions - 933 Solid State PhysicsSolid State Physics - 951 Materials ScienceMaterials Science
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Optical properties and Judd-Ofelt analysis of a novel europium pentafluoropropionate complex with 2,2′-bipyridine
Li, Dong-Dong1, 2; She, Jiang-Bo2; Nie, Rong-Zhi2; Peng, Bo2 Source: Optik, v 127, n 4, p 2059-2061, February 1, 2016
; ISSN: 00304026; DOI: 10.1016/j.ijleo.2015.11.130;
Publisher: Elsevier GmbHAuthor affiliation: 1 School of Electronic Engineering, Xi'An University of Post and Telecommunications, Xi'an, China2 State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Science (CAS), Xi'an, China
Abstract: Europium pentafluoropropionate 2,2′-bipyridine complex, Eu(C2F5COO)3·bpy (bpy = 2,2′-bipyridine), were synthesized and characterized by elemental analysis, Fourier transform infrared spectroscopy (FT-IR), photoluminescence (PL) spectroscopy and thermogravimetric analysis (TA).The excitation spectra of the complex demonstrate that the energy collected by "antenna ligands" was transferred to Eu3+ions efficiently. The room-temperature PL spectra of the complex is composed of the typical Eu3+ions red emission, due to transitions between5D0→7FJ(J=0→4). The lifetimes of5D0of Eu3+in the complex were examined using time-resolved spectroscopic analysis, and the lifetime values of Eu(C2F5COO)3·bpy were fitting with monoexponential (2585 μs) curve. The decomposition temperature of the complex was 262 °C, which indicates the host complex was quite stable to heat. According to the fluorescence emission spectra, the Judd-Ofelt parameters Ω2, Ω4of the complexes were calculated and the radiative properties were also presented. The5D0radiative lifetime, quantum yield and the stimulated emission cross-section of the complex is excellent, which prove that this complex will be promising material for laser application. © 2015 Elsevier GmbH. (12 refs.)Main Heading: EuropiumControlled terms: Curve fitting - Emission spectroscopy - Fourier transform infrared spectroscopy - Judd-Ofelt theory - Laser theory - Optical properties - Photoluminescence spectroscopy - Single crystals - Spectroscopic analysis - Thermogravimetric analysisUncontrolled terms: Bipyridines - Decomposition temperature - Fluorescence emission spectra - Fourier transform infra red (FTIR) spectroscopy - Judd-Ofelt parameters - Laser materials - Radiative properties - Stimulated emission cross sectionClassification Code: 547.2 Rare Earth MetalsRare Earth Metals - 741.1 Light/OpticsLight/Optics - 741.3 Optical Devices and SystemsOptical Devices and Systems - 744.1 Lasers, GeneralLasers, General - 801 ChemistryChemistry - 921.6 Numerical MethodsNumerical Methods - 931.3 Atomic and Molecular PhysicsAtomic and Molecular Physics - 933.1 Crystalline SolidsCrystalline Solids
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Optical waveguides fabricated by nitrogen ion implantation in fused silica
Liu, Chun-Xiao1; Fu, Li-Li2; Zheng, Rui-Lin1; Guo, Hai-Tao3; Zhou, Zhi-Guang3; Li, Wei-Nan3; Lin, She-Bao4; Wei, Wei1 Source: Optical Engineering, v 55, n 2, February 1, 2016
; ISSN: 00913286, E-ISSN: 15602303; DOI: 10.1117/1.OE.55.2.027105; Article number: 027105;
Publisher: SPIEAuthor affiliation: 1 Nanjing University of Posts and Telecommunications, School of Optoelectronic Engineering, No. 9 Wenyuan Road, Yadong New District, Nanjing, Jiangsu, China2 Nanjing University of Posts and Telecommunications, College of Electronic Science and Engineering, No. 9 Wenyuan Road, Yadong New District, Nanjing, Jiangsu, China3 Xi'an Institute of Optics and Precision Mechanics, State Key Laboratory of Transient Optics and Photonics, Chinese Academy of Sciences, No. 17 Xinxi Road, Xi'an, Shaanxi, China4 Baoji University of Arts and Sciences, Institute of Physics and Optoelectronics Technology, No. 44 Baoguang Road, Baoji, Shaanxi, China
Abstract: We report on the fabrication of waveguides in fused silica using 4.5-MeV nitrogen ion implantation with a fluence of 5.0×1014 ions/cm2. The prism-coupling method was employed to measure the effective refractive indices of guiding modes at the wavelengths of 632.8 and 1539 nm. The effective refractive indices of the first few modes were higher than that of the substrate. The refractive index profiles at 632.8 and 1539 nm were reconstructed by the reflectivity calculation method. Positive index changes were induced in the waveguide layers. The end-face coupling method was used to measure the near-field light intensity distributions at the wavelength of 632.8 nm and the finite-difference beam propagation method was applied to simulate the guided mode profile at the wavelength of 1539 nm. The waveguide structures emerge as candidates for integrated photonic devices. © 2016 Society of Photo-Optical Instrumentation Engineers (SPIE). (34 refs.)Main Heading: Fused silicaControlled terms: Beam propagation method - Ion implantation - Ions - Nitrogen - Optical waveguides - Photonic devices - Refractive index - Silica - WaveguidesUncontrolled terms: Effective refractive index - Finite difference beam propagation method - Integrated photonic devices - Nitrogen ion implantations - Prism coupling method - Refractive index profiles - Waveguide layers - Waveguide structureClassification Code: 711 Electromagnetic WavesElectromagnetic Waves - 714.3 WaveguidesWaveguides - 741 Light, Optics and Optical DevicesLight, Optics and Optical Devices - 741.1 Light/OpticsLight/Optics - 804 Chemical Products GenerallyChemical Products Generally - 812.3 GlassGlass - 921 MathematicsMathematics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


X-ray focusing optics and its application in X-ray communication system
Liu, Duo1, 2; Qiang, Peng-Fei1; Li, Lin-Sen1, 2; Su, Tong1; Sheng, Li-Zhi1; Liu, Yong-An1; Zhao, Bao-Sheng1 Source: Wuli Xuebao/Acta Physica Sinica, v 65, n 1, January 5, 2016; Language: Chinese
; ISSN: 10003290; DOI: 10.7498/aps.65.010703; Article number: 010703;
Publisher: Institute of Physics, Chinese Academy of SciencesAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Science, Xi'an, China2 University of Chinese Academy of Sciences, Beijing, China
Abstract: X-ray communication, which was first introduced by Keith Gendreau in 2007, is potential to compete with conventional communication methods, such as microware and laser communication, against space surroundings. Researchers have spent much time and effort on the mission making the initial idea into reality in recent years. Eventually, the X-ray communication demonstration system based on the grid-controlled X-ray source and single-photon detection technique can deliver both audio and video information in a 6-meter vacuum tunnel, and the bit-error-rate performance of the communication system is analyzed. But it is difficult to implement applications in industries. The point is to find a way to reduce the signal divergence geometrical attenuation and increase the distance of the communication which can be regarded as an important foundation of future deep-space X-ray communication applications. Therefore, it is urgent to study the X-ray communication system. By using a nested X-ray focusing optics as transmitting and receiving antennas of the communication system, the signal gain and the distance of X-ray communication can be greatly improved. Specifically, the nested X-ray focusing optics is similar to the Wolter type I telescope, which is widely used in the field of X-ray astronomy. The difference between them is that the Wolter type I optics is originally proposed based on a paraboloid mirror and a hyperboloid mirror, but X-ray focusing optics, the simplified Wolter type I optics, provides a single reflection by a conical approximation mirror, and it is more suitable for X-ray communication. In this paper, aiming at the future demand of X-ray communication, the optimization and analysis of the nested X-ray focusing optics are carried out, and the recurrence relations between the layers of mirrors are derived. Reasonable initial structural parameters and structure of the optics are designed. In addition, the theoretical effective collection area is calculated. Feasibility of using the X-ray focusing optics as transmitting and receiving antennas is analyzed, and the theory and structural design of the X-ray focusing optical are discussed. Signal divergence of transmitting antenna, effective area of receiving antenna, the focal spot size, and the signal gain properties are preliminary studied. The results show that the signal divergence is about 3 mrad, and the transmit gain is 23 dB; the effective area of receiving antenna is 5700 mm2at 1.5 keV. Moreover, the focal spot diameter and the receive gain are 4.5 mm and 25 dB, respectively, and the total gain of this communication system can reach up to 48 dB. © 2016 Chinese Physical Society. (12 refs.)Main Heading: FocusingControlled terms: Antennas - Bit error rate - Mirrors - Particle beams - Receiving antennasUncontrolled terms: Bit error rate (BER) performance - Communication antennas - Communication application - Communication method - Conical approximations - Signal gain - Single photon detection - X-ray focusing opticsClassification Code: 723.1 Computer ProgrammingComputer Programming - 741.3 Optical Devices and SystemsOptical Devices and Systems - 932.1 High Energy PhysicsHigh Energy Physics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Wireless and sensorless 3D ultrasound imaging
Gao, Haitao1, 2; Huang, Qinghua1, 2; Xu, Xiangmin1; Li, Xuelong3 Source: Neurocomputing, v 195, p 159-171, June 26, 2016
; ISSN: 09252312, E-ISSN: 18728286; DOI: 10.1016/j.neucom.2015.08.109;
Publisher: ElsevierAuthor affiliation: 1 School of Electronic and Information Engineering, South China University of Technology, Guangzhou, China2 Hubei Key Laboratory of Intelligent Vision Based Monitoring for Hydroelectric Engineering, China Three Gorges University, Yichang, China3 Center for OPTical IMagery Analysis and Learning (OPTIMAL), State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, Shaanxi, China
Abstract: The past decade has witnessed great advances in three-dimensional (3-D) medical ultrasound (US) imaging instrumentation. An increasing demand for portable 3-D US equipment is one of the main trends upcoming in the market. In this study, we developed a low cost, portable, sensorless and wireless 3-D US imaging system. A laptop US scanner with a conventional linear probe and a convex probe was used to acquire 2-D US B-scans. A client program was developed and run on the US scanner for capturing the pictures of screen during a freehand scanning without a positional sensor, and then the JPEG compression was applied to the pictures for reducing the image data size. The image data was sent to a remote workstation in real-time through Wi-Fi connection. A neural network model was used to recognize the characters (e.g. imaging depth and probe model information) displayed on the screen of the US scanner. The server on the remote workstation communicated with the US scanner, received raw image data, and finally reconstructed 3-D US images. The positions of the B-scans were obtained by estimating the spacings of B-scan image sequence, which was learned by measuring adaptive speckle decorrelation curves in mechanically collected B-scan frames. The performance of the proposed system has been demonstrated through experiments conducted on a US resolution phantom in vitro as well as human tissues in vivo. © 2016 Elsevier B.V. (34 refs.)Main Heading: Medical imagingControlled terms: Probes - Scanning - Speckle - Ultrasonic imaging - Wireless telecommunication systemsUncontrolled terms: 3-D ultrasound - 3D ultrasound imaging - Medical ultrasound - Neural network model - Speckle decorrelation - Threedimensional (3-d) - Volume reconstruction - Wireless communications
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


New light-control technology research of CCD camera
Wang, Xiaotao1, 2; Wang, Xu'an1, 2, 3, 4; Kang, Ning3, 4 Source: Hongwai yu Jiguang Gongcheng/Infrared and Laser Engineering, v 45, n 1, January 25, 2016; Language: Chinese
; ISSN: 10072276; DOI: 10.3788/IRLA201645.0120003; Article number: 0120003;
Publisher: Chinese Society of AstronauticsAuthor affiliation: 1 Xi'an Institute of Optics and Precision Mechanics of CAS, Xi'an, China2 University of Chinese Academy of Sciences, Beijing, China3 Xi'an Modern Technology Institute of Control, Xi'an, China4 Xi'an Guide Technology Co., Ltd, Xi'an, China
Abstract: The exposure time and signal gain can be used to adjust the light intensity for a conventional CCD camera, but both of them can not be configured best. It is also very difficult to maximize the effectiveness of their dimming, especially for the condition of the changed illumination intensity, the large dynamic range and the unclear picture. For the above-mentioned shortages, the histogram equalization certain improvements, the deployment of exposure time and signal gain were optimized through precise deployment of exposure time and optimization of signal gain coefficients. After the test, the screen effect has been significantly improved, the adjustment time is less than 40 ms, and the system is stable and reliable. © 2016, Editorial Board of Journal of Infrared and Laser Engineering. All right reserved. (8 refs.)Main Heading: CCD camerasControlled terms: Graphic methodsUncontrolled terms: Adjustment time - Automatic exposure - Gray scale - Histogram - Histogram equalizations - Illumination intensity - Signal gain - Signal gain coefficientsClassification Code: 714.2 Semiconductor Devices and Integrated CircuitsSemiconductor Devices and Integrated Circuits
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Non-invasive investigation of microstructure of ding kiln porcelain with optical coherence tomography
Yang, Shanshan1, 2; Mi, Lei1; Zhu, Rui1, 2; Liu, Haiping2 Source: Zhongguo Jiguang/Chinese Journal of Lasers, v 43, n 2, February 10, 2016; Language: Chinese
; ISSN: 02587025; DOI: 10.3788/CJL201643.0208002; Article number: 0208002;
Publisher: Science PressAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; Shaanxi, China2 University of Chinese Academy of Sciences, Beijing, China
Abstract: Optical coherence tomography (OCT) is a non-destructive subsurface tomography system based on low coherence interferometry. Non-invasive nature and high speed of acquisition of OCT make it possible to image relic and provide subsurface morphology visualization. Porcelain from Ding kiln of Northern Song Dynasty is scanned and imaged to visualize the subsurface morphology of the surface glaze and core. Layer structures and interfaces can be visualized clearly from OCT images. The characteristics of the thickness of the glaze layer, bubbles and crystal particles in glaze, the penetration depth of OCT in porcelain are analyzed. © 2016, Chinese Laser Press. All right reserved. (25 refs.)Main Heading: Optical tomographyControlled terms: Crystallography - Glazes - Imaging systems - Kilns - Porcelain - TomographyUncontrolled terms: Core - Crystal particles - Glaze layers - High Speed - Layer structures - Low coherence interferometry - Non destructive - Tomography systemClassification Code: 642.2 Industrial Furnaces and ComponentsIndustrial Furnaces and Components - 741.3 Optical Devices and SystemsOptical Devices and Systems - 746 Imaging TechniquesImaging Techniques - 812.1 CeramicsCeramics - 813.2 Coating MaterialsCoating Materials - 933.1 Crystalline SolidsCrystalline Solids
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Design of Fiber Bragg Grating automatic analysis test system based on LabVIEW
Liu, Chun-Tong1; Li, Hong-Cai1; He, Zhen-Xin1; Wu, Guo-Jun2 Source: Guangzi Xuebao/Acta Photonica Sinica, v 45, n 2, February 1, 2016
; ISSN: 10044213; DOI: 10.3788/gzxb20164502.0206002; Article number: 0206002;
Publisher: Chinese Optical SocietyAuthor affiliation: 1 the Second Artillery Engineering University, Xi'an, China2 Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, China
Abstract: For the purpose of realizing the Fiber Bragg Grating (FBG) sensing system automated test and analysis, a friendly interface of FBG sensing test system based on LabVIEW was designed by using the remote control port of Q8384 spectrometer. The strain/force integrated tester was used for tension test of a steel beam with embedded FBG packaged, the experiment data was acquired and analyzed by LabVIEW automatic testing platform, the results were in line with the design expectations, and the system realized the real-time monitoring and data storage capabilities. The tested device is easy to manage, and the direct operation on spectrometer is avoided, which can extend the service life of the spectrometer. © 2016, Science Press. All right reserved. (19 refs.)Main Heading: Fiber Bragg gratingsControlled terms: Automatic testing - Bragg gratings - Digital storage - Remote control - Remote sensing - Spectrometers - Steel testing - Tensile testingUncontrolled terms: Automated test - Automatic analysis - Data storage capability - Experiment data - LabViEW - Real time monitoring - Sensing systems - Tested devicesClassification Code: 545.3 SteelSteel - 722.1 Data Storage, Equipment and TechniquesData Storage, Equipment and Techniques - 731.1 Control SystemsControl Systems - 741.3 Optical Devices and SystemsOptical Devices and Systems
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Fundamental-frequency-absorbed oxyfluoride glass in a high-power laser
Hou, Chaoqi1; Li, Weinan1; Pengfei, Wang1; Lu, Min1; Bo, Peng1; Haitao, Guo1; Fei, Gao1; Xiaoxia, Cui1 Source: Applied Optics, v 55, n 10, p 2649-2652, April 1, 2016
; ISSN: 1559128X, E-ISSN: 21553165; DOI: 10.1364/AO.55.002649;
Publisher: OSA - The Optical SocietyAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Science (CAS), Xi'an, China
Abstract: A high-power third-harmonic laser faces challenges in the filtering remnant unconverted fundamental frequency, which is from the frequency converting crystal. In this work, a novel fundamental-frequency-absorbed oxyfluoride glass has been prepared, which provides a possible option to solve the problem. By being doped with Fe2 ion, the glass shows strong absorption property at 1053 nm, and the glass's transmittances at 351 and 1053 nm are stable with changing the laser power or increasing the irradiation times under high-power laser irradiation. Meanwhile, the laser-induced damage threshold of the glass is 12.5 J/cm2 at 351 nm, which is two times higher than that of fused silica whose threshold is 6.2 J/cm2 in the same testing condition. The glass also exhibits a higher laserinduced damage threshold as well as 36.6 J/cm2 at its absorption wavelength of 1053 nm. The results indicate that this glass is promising as a color-separation optic, thus allowing a novel design for the final optics assembly in an inertial confinement fusion laser system. © 2016 Optical Society of America. (23 refs.)Main Heading: GlassControlled terms: Fused silica - High power lasers - Irradiation - Laser damage - Natural frequenciesUncontrolled terms: Absorption wavelengths - Color separation - Fundamental frequencies - Laser induced damage thresholds - Oxy-fluoride glass - Strong absorptions - Testing conditions - Third harmonicClassification Code: 744.1 Lasers, GeneralLasers, General - 744.8 Laser Beam InteractionsLaser Beam Interactions - 812.3 GlassGlass
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Aging Face Recognition: A Hierarchical Learning Model Based on Local Patterns Selection
Li, Zhifeng1; Gong, Dihong1; Li, Xuelong2; Tao, Dacheng3 Source: IEEE Transactions on Image Processing, v 25, n 5, p 2146-2154, May 2016
; ISSN: 10577149; DOI: 10.1109/TIP.2016.2535284; Article number: 7420684;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China2 Center for OPTical IMagery Analysis and Learning (OPTIMAL), Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, China3 Centre for Quantum Computation and Intelligent Systems, Faculty of Engineering and Information Technology, University of Technology Sydney, 81 Broadway Street, Ultimo; NSW, Australia
Abstract: Aging face recognition refers to matching the same person's faces across different ages, e.g., matching a person's older face to his (or her) younger one, which has many important practical applications, such as finding missing children. The major challenge of this task is that facial appearance is subject to significant change during the aging process. In this paper, we propose to solve the problem with a hierarchical model based on two-level learning. At the first level, effective features are learned from low-level microstructures, based on our new feature descriptor called local pattern selection (LPS). The proposed LPS descriptor greedily selects low-level discriminant patterns in a way, such that intra-user dissimilarity is minimized. At the second level, higher level visual information is further refined based on the output from the first level. To evaluate the performance of our new method, we conduct extensive experiments on the MORPH data set (the largest face aging data set available in the public domain), which show a significant improvement in accuracy over the state-of-the-art methods. © 2015 IEEE. (71 refs.)Main Heading: Face recognitionControlled terms: Hierarchical systemsUncontrolled terms: Different ages - Facial appearance - Feature descriptors - Hierarchical learning - Hierarchical model - Missing children - State-of-the-art methods - Visual informationClassification Code: 961 Systems ScienceSystems Science
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Corrigendum to 'Material research on the InGaAs-emitting-layer VECSEL grown on GaAs substrate' [Mater. Sci. Semicond. Process. 42 (2016) 283-287]
Lin, Tao1; Sun, Ruijuan1; Sun, Hang1; Guo, Enmin1; Duan, Yupeng2; Lin, Nan3; Ma, Xiaoyu3; Wang, Yonggang4 Source: Materials Science in Semiconductor Processing, v 47, p 86, June 1, 2016
; ISSN: 13698001; DOI: 10.1016/j.mssp.2016.03.030;
Publisher: Elsevier LtdAuthor affiliation: 1 Department of Electronic Engineering, Xi'an University of Technology, Xi'an, China2 Department of Physics, Northwest University, Xi'an, China3 Institute of Semiconductors, Chinese Academy of Sciences, Beijing, China4 Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, China (2 refs.)
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Experimental demonstration of 3D Accelerating beam arrays
Yu, Xianghua1; Li, Runze1; Yan, Shaohui1; Yao, Baoli1; Gao, Peng1; Han, Guoxia1; Lei, Ming1 Source: Applied Optics, v 55, n 11, p 3090-3095, April 10, 2016
; ISSN: 1559128X, E-ISSN: 21553165; DOI: 10.1364/AO.55.003090;
Publisher: OSA - The Optical SocietyAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, China
Abstract: Accelerating beams have attracted much attention in the frontiers of optical physics and technology owing to their unique propagation dynamics of nondiffracting, self-healing, and freely accelerating along curved trajectories. Such behaviors essentially arise from the particular phase factor occurring in their spatial frequency spectrum, e.g., the cubic phase associated to the spectrum of Airy beam. In this paper, we theoretically and experimentally demonstrate a sort of accelerating beam arrays, which are composed of spatially separated accelerating beams. By superimposing kinoforms of multifocal patterns into the spatial frequency spectrum of accelerating beams, different types of beam arrays, e.g., Airy beam arrays and two-main-lobe accelerating beam arrays, are generated and measured by scanning a reflection mirror near the focal region along the optical axis. The 3D intensity patterns reconstructed from the experimental data present good agreement with the theoretical counterparts. The combination of accelerating beams with optical beam arrays proposed here may find potential applications in various fields such as optical microscopes, optical micromachining, optical trapping, and so on. © 2016 Optical Society of America. (31 refs.)Main Heading: SpectroscopyControlled terms: Molecular physics - OpticsUncontrolled terms: Experimental demonstrations - Intensity patterns - Optical microscopes - Optical physics - Opticaltrapping - Propagation dynamics - Reflection mirrors - Spatial frequency spectrumsClassification Code: 741.1 Light/OpticsLight/Optics - 931.3 Atomic and Molecular PhysicsAtomic and Molecular Physics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Planar waveguides in neodymium-doped calcium niobium gallium garnet crystals produced by proton implantation
Liu, Chun-Xiao1; Chen, Meng1; Fu, Li-Li2; Zheng, Rui-Lin1; Guo, Hai-Tao3; Zhou, Zhi-Guang3; Li, Wei-Nan3; Lin, She-Bao4; Wei, Wei1 Source: Chinese Physics B, v 25, n 4, April 2016
; ISSN: 16741056; DOI: 10.1088/1674-1056/25/4/044211; Article number: 044211;
Publisher: Institute of Physics PublishingAuthor affiliation: 1 School of Optoelectronic Engineering, Nanjing University of Posts and Telecommunications, Nanjing, China2 College of Electronic Science and Engineering, Nanjing University of Posts and Telecommunications, Nanjing, China3 State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, China4 Institute of Physics and Optoelectronics Technology, Baoji University of Arts and Sciences, Baoji, China
Abstract: In this work, the fabrication and optical properties of a planar waveguide in a neodymium-doped calcium niobium gallium garnet (Nd:CNGG) crystal are reported. The waveguide is produced by proton (H+) implantation at 480 keV and a fluence of 1.01017ions/cm2. The prism-coupling measurement is performed to obtain the dark mode of the waveguide at a wavelength of 632.8 nm. The reflectivity calculation method (RCM) is used to reconstruct the refractive index profile. The finite-difference beam propagation method (FD-BPM) is employed to calculate the guided mode profile of the waveguide. The stopping and range of ions in matter 2010 (SRIM 2010) code is used to simulate the damage profile induced by the ion implantation. The experimental and theoretical results indicate that the waveguide can confine the light propagation. © 2016 Chinese Physical Society and IOP Publishing Ltd. (20 refs.)Main Heading: Light propagationControlled terms: Beam propagation method - Calcium - Garnets - Ion implantation - Ions - Laser optics - Neodymium - Niobium - Optical properties - Optical waveguides - Planar waveguides - Refractive index - WaveguidesUncontrolled terms: Damage profiles - Finite-difference beam propagation method - Garnet crystals - Neodymium doped - Prism-coupling measurements - Proton implantation - Refractive index profiles - Stopping and range of ions in mattersClassification Code: 547.2 Rare Earth MetalsRare Earth Metals - 549.2 Alkaline Earth MetalsAlkaline Earth Metals - 549.3 Nonferrous Metals and Alloys excluding Alkali and Alkaline Earth Metals Nonferrous Metals and Alloys excluding Alkali and Alkaline Earth Metals - 711 Electromagnetic WavesElectromagnetic Waves - 714.3 WaveguidesWaveguides - 741 Light, Optics and Optical DevicesLight, Optics and Optical Devices - 741.1 Light/OpticsLight/Optics - 921 MathematicsMathematics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Action recognition by joint learning
Yuan, Yuan1; Qi, Lei1; Lu, Xiaoqiang1 Source: Image and Vision Computing, v 55, p 77-85, November 1, 2016
; ISSN: 02628856; DOI: 10.1016/j.imavis.2016.04.001;
Publisher: Elsevier LtdAuthor affiliation: 1 Center for OPTical IMagery Analysis and Learning (OPTIMAL), Chinese Academy of Sciences State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Xi'an; Shaanxi; 710119, China
Abstract: Due to the promising applications including video surveillance, video annotation, and interaction gaming, human action recognition from videos has attracted much research interest. Although various works have been proposed for human action recognition, there still exist many challenges such as illumination condition, viewpoint, camera motion and cluttered background. Extracting discriminative representation is one of the main ways to handle these challenges. In this paper, we propose a novel action recognition method that simultaneously learns middle-level representation and classifier by jointly training a multinomial logistic regression (MLR) model and a discriminative dictionary. In the proposed method, sparse code of low-level representation, conducting as latent variables of MLR, can capture the structure of low-level feature and thus is more discriminate. Meanwhile, the training of dictionary and MLR model are integrated into one objective function for considering the information of categories. By optimizing this objective function, we can learn a discriminative dictionary modulated by MLR and a MLR model driven by sparse coding. The proposed method is evaluated on YouTube action dataset and HMDB51 dataset. Experimental results demonstrate that our method is comparable with mainstream methods. © 2016 Elsevier B.V. (40 refs.)Main Heading: Motion estimationControlled terms: Codes (symbols) - Computer vision - Gesture recognition - Motion analysis - Regression analysis - Security systemsUncontrolled terms: Action recognition - Discriminative dictionaries - Human-action recognition - Illumination conditions - Joint learning - Low level representation - Multinomial logistic regression - Sparse coding
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Research on temperature tuning properties of chirped fiber grating
Zhang, Xin1; Yang, Zhi1; Li, Qianglong1; Li, Feng1; Yang, Xiaojun1; Wang, Yishan1; Zhao, Wei1 Source: Guangxue Xuebao/Acta Optica Sinica, v 36, n 5, May 10, 2016; Language: Chinese
; ISSN: 02532239; DOI: 10.3788/AOS201636.0505002; Article number: 0505002;
Publisher: Chinese Optical SocietyAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; Shaanxi; 710119, China
Abstract: According to the temperature tenability of chirped fiber grating, the minimum output pulse width can be obtained by controlling the fiber grating's temperature to change the dispersion of the chirped fiber grating, and the feasibility of this idea is demonstrated through experiments. The chirped fiber grating is used as the stretcher in the fiber chirped pulse amplification (CPA) system, and the gratings-pair is used as compressor. The positive dispersion brought by the stretcher is compensated by the negative dispersion provided by the compressor. The output pulse width is measured by the auto-correlation for denoting the dispersion of the chirped fiber Bragg grating indirectly as a function of temperature. It can be seen from the obtained experimental data that, when the temperature rises from -7℃ to 50℃, the pulse width falls from 1057 fs to 764 fs, and then rises to 910 fs, with a total change of 439 fs achieved. In the experiment, dispersion increases with temperature rising, changing from insufficient dispersion compensation to over dispersion compensation. © 2016, Chinese Lasers Press. All right reserved. (11 refs.)Main Heading: Ultrashort pulsesControlled terms: Chirp modulation - Diffraction gratings - Dispersion (waves) - Dispersion compensation - Fiber Bragg gratings - Fibers - StretchersUncontrolled terms: Chirped fiber Bragg grating - Chirped fiber grating - Chirped pulse amplification systems - Fiber gratings - Over dispersion - Temperature rise - Temperature rising - Temperature tuningClassification Code: 462.1 Biomedical Equipment, GeneralBiomedical Equipment, General - 716 Telecommunication; Radar, Radio and TelevisionTelecommunication; Radar, Radio and Television - 741.3 Optical Devices and SystemsOptical Devices and Systems
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


All-optical control of microfiber resonator by graphene's photothermal effect
Wang, Yadong1; Gan, Xuetao1; Zhao, Chenyang1; Fang, Liang1; Mao, Dong1; Xu, Yiping2; Zhang, Fanlu1; Xi, Teli1; Ren, Liyong2; Zhao, Jianlin1 Source: Applied Physics Letters, v 108, n 17, April 25, 2016
; ISSN: 00036951; DOI: 10.1063/1.4947577; Article number: 171905;
Publisher: American Institute of Physics Inc.Author affiliation: 1 Key Laboratory of Space Applied Physics and Chemistry, Ministry of Education, Shaanxi Key Laboratory of Optical Information Technology, School of Science, Northwestern Polytechnical University, Xi'an; 710072, China2 State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China
Abstract: We demonstrate an efficient all-optical control of microfiber resonator assisted by graphene's photothermal effect. Wrapping graphene onto a microfiber resonator, the light-graphene interaction can be strongly enhanced via the resonantly circulating light, which enables a significant modulation of the resonance with a resonant wavelength shift rate of 71 pm/mW when pumped by a 1540 nm laser. The optically controlled resonator enables the implementation of low threshold optical bistability and switching with an extinction ratio exceeding 13 dB. The thin and compact structure promises a fast response speed of the control, with a rise (fall) time of 294.7 μs (212.2 μs) following the 10%-90% rule. The proposed device, with the advantages of compact structure, all-optical control, and low power acquirement, offers great potential in the miniaturization of active in-fiber photonic devices. © 2016 Author(s). (28 refs.)Main Heading: ResonatorsControlled terms: Graphene - Photonic devices - Pumping (laser)Uncontrolled terms: All optical - Compact structures - Extinction ratios - Fast response - Low thresholds - Optically controlled - Photothermal effects - Resonant wavelengthsClassification Code: 741.1 Light/OpticsLight/Optics - 744.1 Lasers, GeneralLasers, General - 761 NanotechnologyNanotechnology - 804 Chemical Products GenerallyChemical Products Generally
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Optimization design of C-T imaging spectrometer based on the tilt field len
Hao, Ai-Hua1; Hu, Bing-Liang2; Li, Li-Bo2; Li, Yun2 Source: Guangzi Xuebao/Acta Photonica Sinica, v 45, n 4, April 1, 2016; Language: Chinese
; ISSN: 10044213; DOI: 10.3788/gzxb20164504.0412002; Article number: 0412002;
Publisher: Chinese Optical SocietyAuthor affiliation: 1 School of Electronic Engineering, Xi'an University of Post and Telecommunications, Xi'an; 710121, China2 Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China
Abstract: Residual smile limits the application of Czerny-Turner plane grating spectrometer in the imaging spectrometer. In this paper, different from the traditional method of smile correction based on prism, a method is proposed, which is based on the tilt field mirror. The field curve is corrected, at the same time, the different wavelength slit images in different regions of the field lens are corrected, and the other optical properties of the system are not changed. The Czerny Turner imaging spectrometer slit is 7.8 millimeter length and 0.016 millimeter wide, spectral range from 0.31 to 0.5 microns, spectral resolution 0.4 nanometers, the object focal length 70 millimeters, 1:1 magnification. Optimization design results, MTF over 0.8, RMS spot radius less than 9 microns, the relative smile less than 0.2%, meet the design requirements. It shows that the method can be used in the systems with weak signal and low transmittance optical glass. © 2016, Chinese Optical Society. All right reserved. (14 refs.)Main Heading: SpectrometersControlled terms: Design - Lenses - Optical design - Optical glass - Optical properties - SilicaUncontrolled terms: Czerny-Turner - Field lens - Grating imaging - Imaging spectrometers - Optimization design - Plane grating - Smile - Spectral rangeClassification Code: 741.1 Light/OpticsLight/Optics - 741.3 Optical Devices and SystemsOptical Devices and Systems
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Influence of three-point-mount-induced deformation for a three-mirror-anastigmatic telescope on its astigmatic field
Zou, Gangyi1, 2; Fan, Xuewu1; Pang, Zhihai1; Wang, Chenchen1, 2; Li, Ruichang1, 2 Source: Guangxue Xuebao/Acta Optica Sinica, v 36, n 6, June 10, 2016; Language: Chinese
; ISSN: 02532239; DOI: 10.3788/AOS201636.0622002; Article number: 0622002;
Publisher: Chinese Optical SocietyAuthor affiliation: 1 Space Optics Laboratory, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; Shaanxi; 710119, China2 University of Chinese Academy of Sciences, Beijing; 100049, China
Abstract: In order to improve the efficiency of alignment for a three-mirror-anastigmatic (TMA) telescope with large aperture, the influence of three point mount induced (TPMI) deformation on its astigmatic field distribution in the aligning process is analyzed. Based on the vector aberration theory and aperture coordinate transformation, the astigmatic field distribution characters for the aligned and misaligned TMA telescope are analyzed with TPMI deformation on mirrors located at or away from the aperture stop. Finally, the surface error due to TPMI deformation is simulated by the optical design software CODE V using Z10and Z11, the terms of fringe Zernike polynomial. The characteristic field distribution of astigmatism is verified by the real-ray-tracing method. The results indicate that the astigmatic field distributions are not affected when the TPMI deformation is on the primary mirror (aperture stop), and it shows different characteristic field distributions when the TPMI deformation is on the secondary or tertiary mirror (not aperture stop) for the aligned or misaligned telescope because of producing astigmatism with the field conjugated and field linear. The aligning state of TMA telescope can be qualitatively analyzed by its astigmatic field distribution at the final aligning stage, which is quite instructive for the alignment of TMA telescopes with large aperture. © 2016, Chinese Lasers Press. All right reserved. (17 refs.)Main Heading: TelescopesControlled terms: Deformation - Mirrors - Optical design - Ray tracingUncontrolled terms: Aperture coordinates - Astigmatic field - Field distribution - Optical-design software - Primary mirrors - Real ray tracing - Vector aberration - Zernike polynomialsClassification Code: 741.1 Light/OpticsLight/Optics - 741.3 Optical Devices and SystemsOptical Devices and Systems
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Wave-front coded super-resolution imaging technique
Zhao, Hui1; Wei, Jingxuan2; Pang, Zhihai1; Liu, Meiying1 Source: Hongwai yu Jiguang Gongcheng/Infrared and Laser Engineering, v 45, n 4, April 25, 2016; Language: Chinese
; ISSN: 10072276; DOI: 10.3788/IRLA201645.0422003; Article number: 0422003;
Publisher: Chinese Society of AstronauticsAuthor affiliation: 1 Space Optics Lab Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China2 School of Computer Science and Technology, Xidian University, Xi'an; 710071, China
Abstract: Wave-front coding is a classical computational imaging technique and famous for its capability in extending the depth of focus (DOF) of incoherent imaging system. In fact, besides the DOF extension, this technique has the potentials in realizing super-resolution imaging, which is rare to be investigated in existing literatures. On the one hand, the introduction of phase mask makes defocus invariance of optical transfer function (OTF) possible and the dramatic decrease of modulus of OTF alleviates the aliasing effect owned by most digital imaging systems. In this case, a better image data suitable for super-resolution imaging could be provided. On the other hand, the prominent expansion of point spread function (PSF) allows us to obtain the real sampled PSF corresponding to any specific pitch size in a digital way using the ideal continuous optical PSF whose sampling interval could be considered as unlimitedly small. Therefore, based on these two characteristics, an amplification based single image super-resolution reconstruction algorithm was especially designed for wave-front coded imaging system and an experimental prototype camera has been fabricated to verify the effectiveness of the algorithm. The results demonstrate that the extended DOF which is more than 20 times original DOF has been obtained and at least 3X super-resolution reconstruction effect could be achieved. Besides that, the quality of reconstructed image approaches the diffraction limited level. © 2016, Editorial Board of Journal of Infrared and Laser Engineering. All right reserved. (28 refs.)Main Heading: Image reconstructionControlled terms: Image processing - Image resolution - Imaging systems - Imaging techniques - Light polarization - Optical design - Optical resolving power - Optical transfer function - WavefrontsUncontrolled terms: Computational imaging - Depth of focus - Quality of reconstructed images - Single-image super-resolution reconstruction - Super resolution - Super resolution imaging - Super resolution reconstruction - Wave-front codingClassification Code: 741.1 Light/OpticsLight/Optics - 746 Imaging TechniquesImaging Techniques
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Detector for space thermalion imaging
Li, Lin-Sen1, 2; Liu, Yong-An1; Kong, Ling-Gao3; Liu, Duo1, 2; Qiang, Peng-Fei1; Zhao, Bao-Sheng1 Source: Guangzi Xuebao/Acta Photonica Sinica, v 45, n 4, April 1, 2016; Language: Chinese
; ISSN: 10044213; DOI: 10.3788/gzxb20164504.0423007; Article number: 0423007;
Publisher: Chinese Optical SocietyAuthor affiliation: 1 Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China2 Xi'an Jiaotong University, Xi'an; 710119, China3 National Space Science Center, Chinese Academy of Sciences, Beijing; 100190, China
Abstract: A kind of space thermal-ion imaging detector was investigated, which can be used in detecting a variety oftargetsource such as thermion, ultraviolet, X-rays etc. The output of the detector is a grayscale image of the target source, the detail information including the gradation level and gradation distribution of the image are obtained based on the intensity and thermal-ion uniformity of the target source. This paper conducted experiments to test the detector with target source of ultraviolet light. Performance parameters as follows have been detected; the resolution is better than 120 μm; the input-output linearity error is <±4% and the output uniformity is better than 97%. © 2016, Chinese Optical Society. All right reserved. (15 refs.)Main Heading: PhotonicsControlled terms: OpticsUncontrolled terms: Gradation analysis - Imaging detector - Thermionic - Ultraviolet - UniformityClassification Code: 741.1 Light/OpticsLight/Optics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Implementation of dispersion-free slow acoustic wave propagation and phase engineering with helical-structured metamaterials
Zhu, Xuefeng1, 2, 3; Li, Kun1; Zhang, Peng4; Zhu, Jie5; Zhang, Jintao1; Tian, Chao6; Liu, Shengchun1, 6 Source: Nature Communications, v 7, May 20, 2016; E-ISSN: 20411723; DOI: 10.1038/ncomms11731; Article number: 11731;
Publisher: Nature Publishing GroupAuthor affiliation: 1 College of Physical Science and Technology, Heilongjiang University, Harbin; 150080, China2 Department of Physics, Huazhong University of Science and Technology, Wuhan; 430074, China3 Innovation Institute, Huazhong University of Science and Technology, Wuhan; 430074, China4 State Key Laboratory of Transient Optics and Photonics, Chinese Academy of Sciences, Xi'an; 710119, China5 Department of Mechanical Engineering, Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong6 Department of Biomedical Engineering, University of Michigan, Ann Arbor; MI; 48109, United States
Abstract: The ability to slow down wave propagation in materials has attracted significant research interest. A successful solution will give rise to manageable enhanced wave-matter interaction, freewheeling phase engineering and spatial compression of wave signals. The existing methods are typically associated with constructing dispersive materials or structures with local resonators, thus resulting in unavoidable distortion of waveforms. Here we show that, with helical-structured acoustic metamaterials, it is now possible to implement dispersion-free sound deceleration. The helical-structured metamaterials present a non-dispersive high effective refractive index that is tunable through adjusting the helicity of structures, while the wavefront revolution plays a dominant role in reducing the group velocity. Finally, we numerically and experimentally demonstrate that the helical-structured metamaterials with designed inhomogeneous unit cells can turn a normally incident plane wave into a self-Accelerating beam on the prescribed parabolic trajectory. The helical-structured metamaterials will have profound impact to applications in explorations of slow wave physics. (51 refs.)Controlled terms: acoustic wave - compression - experimental study - numerical method - refractive index - research work - wave propagation - waveform analysisClassification Code: 901 Geobase: Related TopicsGeobase: Related Topics
Database: GEOBASE
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Weakly Supervised Multilabel Clustering and its Applications in Computer Vision
Xia, Yingjie1; Nie, Liqiang2; Zhang, Luming3; Yang, Yi4; Hong, Richang3; Li, Xuelong5 Source: IEEE Transactions on Cybernetics, v 46, n 12, p 3220-3232, December 2016
; ISSN: 21682267; DOI: 10.1109/TCYB.2015.2501385; Article number: 7426784;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 College of Computer Science, Zhejiang University, Hangzhou; 310027, China2 School of Computer Science and Technology, Shandong University, Jinan; 250100, China3 Department of Computer Science and Information Engineering, Hefei University of Technology, Hefei; 230009, China4 Centre for Quantum Computation and Intelligent Systems, University of Technology Sydney, Ultimo; NSW; 123, Australia5 Center for OPTical IMagery Analysis and Learning, State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China
Abstract: Clustering is a useful statistical tool in computer vision and machine learning. It is generally accepted that introducing supervised information brings remarkable performance improvement to clustering. However, assigning accurate labels is expensive when the amount of training data is huge. Existing supervised clustering methods handle this problem by transferring the bag-level labels into the instance-level descriptors. However, the assumption that each bag has a single label limits the application scope seriously. In this paper, we propose weakly supervised multilabel clustering, which allows assigning multiple labels to a bag. Based on this, the instance-level descriptors can be clustered with the guidance of bag-level labels. The key technique is a weakly supervised random forest that infers the model parameters. Thereby, a deterministic annealing strategy is developed to optimize the nonconvex objective function. The proposed algorithm is efficient in both the training and the testing stages. We apply it to three popular computer vision tasks: 1) image clustering; 2) semantic image segmentation; and 3) multiple objects localization. Impressive performance on the state-of-the-art image data sets is achieved in our experiments. © 2016 IEEE. (54 refs.)Main Heading: Computer visionControlled terms: Artificial intelligence - Decision trees - Image segmentation - Learning systems - Semantics - Statistical mechanicsUncontrolled terms: Deterministic annealing - ITS applications - Model parameters - Multiple objects - Non-convex objective functions - Semantic image segmentations - Statistical tools - Supervised clustering
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Scattering effects and high-spatial-frequency nanostructures on ultrafast laser irradiated surfaces of zirconium metallic alloys with nanoscaled topographies
Li, Chen1, 2, 3; Cheng, Guanghua1; Sedao, Xxx2; Zhang, Wei4; Zhang, Hao2; Faure, Nicolas2; Jamon, Damien2; Colombier, Jean-Philippe2; Stoian, Razvan2 Source: Optics Express, v 24, n 11, p 11558-11568, May 30, 2016; E-ISSN: 10944087; DOI: 10.1364/OE.24.011558;
Publisher: OSA - The Optical SocietyAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, CAS, Xi'an; Shaanxi; 710119, China2 Laboratoire Hubert Curien, UMR 5516 CNRS, Université de Lyon, Université Jean Monnet, Saint Etienne; 42000, France3 University of Chinese Academy of Science, Beijing; 10049, China4 National Key Laboratory of Science and Technology on Power Beam Processes, Beijing Aeronautical Manufacturing Technology Research Institute, Beijing; 100024, China
Abstract: The origin of high-spatial-frequency laser-induced periodic surface structures (HSFL) driven by incident ultrafast laser fields, with their ability to achieve structure resolutions below λ/2, is often obscured by the overlap with regular ripples patterns at quasi-wavelength periodicities. We experimentally demonstrate here employing defined surface topographies that these structures are intrinsically related to surface roughness in the nano-scale domain. Using Zr-based bulk metallic glass (Zr-BMG) and its crystalline alloy (Zr-CA) counterpart formed by thermal annealing from its glassy precursor, we prepared surfaces showing either smooth appearances on thermoplastic BMG or high-density nano-protuberances from randomly distributed embedded nano-crystallites with average sizes below 200 nm on the recrystallized alloy. Upon ultrashort pulse irradiation employing linearly polarized 50 fs, 800 nm laser pulses, the surfaces show a range of nanoscale organized features. The change of topology was then followed under multiple pulse irradiation at fluences around and below the single pulse threshold. While the former material (Zr-BMG) shows a specific high quality arrangement of standard ripples around the laser wavelength, the latter (Zr-CA) demonstrates strong predisposition to form high spatial frequency rippled structures (HSFL). We discuss electromagnetic scenarios assisting their formation based on near-field interaction between particles and field-enhancement leading to structure linear growth. Finite-differencetime-domain simulations outline individual and collective effects of nanoparticles on electromagnetic energy modulation and the feedback processes in the formation of HSFL structures with correlation to regular ripples (LSFL). ©2016 Optical Society of America. (19 refs.)Main Heading: Ultrashort pulsesControlled terms: Electromagnetic waves - Glass - Irradiation - Laser pulses - Metallic glass - Nanotechnology - Surface roughness - Ultrafast lasersUncontrolled terms: Finite difference time domains - High spatial frequency - Laser-induced periodic surface structures - Linearly polarized - Multiple-pulse irradiation - Near field interactions - Randomly distributed - Zr based bulk metallic glassClassification Code: 531 Metallurgy and MetallographyMetallurgy and Metallography - 711 Electromagnetic WavesElectromagnetic Waves - 744.1 Lasers, GeneralLasers, General - 761 NanotechnologyNanotechnology - 812.3 GlassGlass - 931.2 Physical Properties of Gases, Liquids and SolidsPhysical Properties of Gases, Liquids and Solids
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Congested scene classification via efficient unsupervised feature learning and density estimation
Yuan, Yuan1; Wan, Jia2; Wang, Qi2 Source: Pattern Recognition, v 56, p 159-169, August 1, 2016
; ISSN: 00313203; DOI: 10.1016/j.patcog.2016.03.020;
Publisher: Elsevier LtdAuthor affiliation: 1 Center for OPTical IMagery Analysis and Learning (OPTIMAL), State Key Laboratory of Transient Optics and Photonics, Xi׳an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi׳an, Shaanxi; 710119, China2 School of Computer Science and Center for OPTical IMagery Analysis and Learning (OPTIMAL), Northwestern Polytechnical University, Xi׳an, Shaanxi; 710072, China
Abstract: An unsupervised learning algorithm with density information considered is proposed for congested scene classification. Though many works have been proposed to address general scene classification during the past years, congested scene classification is not adequately studied yet. In this paper, an efficient unsupervised feature learning approach with density information encoded is proposed to solve this problem. Based on spherical k-means, a feature selection process is proposed to eliminate the learned noisy features. Then, local density information which better reflects the crowdedness of a scene is encoded by a novel feature pooling strategy. The proposed method is evaluated on the assembled congested scene data set and UIUC-sports data set, and intensive comparative experiments justify the effectiveness of the proposed approach. © 2016 Elsevier Ltd (50 refs.)Main Heading: Classification (of information)Controlled terms: Algorithms - Computer vision - Learning algorithmsUncontrolled terms: Density estimation - Feature pooling - K-means - Scene classification - Unsupervised feature learningClassification Code: 716.1 Information Theory and Signal ProcessingInformation Theory and Signal Processing - 723.5 Computer ApplicationsComputer Applications
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Porous propellant burning rate enhanced by plasma
Ni, Yanjie1; Xing, Rongjun2; Wan, Gang1; Jin, Yong1; Li, Haiyuan1; Yang, Chunxia1; Li, Baoming1 Source: Baozha Yu Chongji/Explosion and Shock Waves, v 36, n 4, p 562-567, July 25, 2016; Language: Chinese
; ISSN: 10011455; DOI: 10.11883/1001-1455(2016)04-0562-06;
Publisher: Explosion and Shock WavesAuthor affiliation: 1 National Key Laboratory of Transient Physics, Nanjing University of Science and Technology, Nanjing; Jiangsu; 210094, China2 Xi'an North Huian Chemical Industry Co., Ltd., Xi'an; Shaanxi; 710302, China
Abstract: The experimental system with a closed bomb was employed to discuss the characteristics of 4/7 high-nitrogen solid propellant burning rate enhanced by plasma. The plasma energy transferred into the closed bomb was measured by the utilization efficiency of the plasma generator electrical energy. A transient burning rate formula of propellant including the influence of pressure gradient and an enhanced gas generation rates coefficient by electrical power was presented. The enhanced gas generation rates coefficient of 4/7 high-nitrogen solid propellant is equal to 0.005 MW-1. Compared with the burning rate formula given by Woodley, the pressure curve simulated by the transient burning rate formula is in better agreement with the tests. And the transient burning rate formula can describe the combustion process of solid propellant by plasma more accurately. © 2016, Editorial Board of EXPLOSION AND SHOCK WAVES. All right reserved. (14 refs.)Main Heading: Nitrogen plasmaControlled terms: Bombs (ordnance) - Gas generators - Nitrogen - Plasmas - Propellants - Solid propellantsUncontrolled terms: Burning rate - Combustion pro-cess - Electrothermal chemical launches - Experimental system - Gas generation rates - Mechanics of explosion - Propellant burning rate - Utilization efficiencyClassification Code: 404 Civil Defense and Military EngineeringCivil Defense and Military Engineering - 522 Gas FuelsGas Fuels - 804 Chemical Products GenerallyChemical Products Generally - 932.3 Plasma PhysicsPlasma Physics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


ZnSe-material phase mask applied to athermalization of infrared imaging systems
Feng, Bin1; Shi, Zelin2, 3; Xu, Baoshu2, 3; Zhang, Chengshuo2, 3; Zhang, Xiaodong4 Source: Applied Optics, v 55, n 21, p 5715-5720, July 20, 2016
; ISSN: 1559128X, E-ISSN: 21553165; DOI: 10.1364/AO.55.005715;
Publisher: OSA - The Optical SocietyAuthor affiliation: 1 School of Optoelectronic Engineering, Xi'an Technological University, Xi'an; 710032, China2 Shenyang Institute of Automation, Chinese Academy of Sciences, Shenyang; 110016, China3 Key Laboratory of Opto-electronic Information Processing, Chinese Academy of Sciences, Shenyang; 110016, China4 State Key Laboratory of Precision Measuring Technology and Instruments, Centre of MicroNano Manufacturing Technology, Tianjin University, Tianjin; 300072, China
Abstract: This paper reports a ZnSe-material phase mask that is applied to athermalization of a conventional infrared imaging system. Its principle, design, manufacture, measurement, and performance validation are successively discussed. This paper concludes that a ZnSe-material phase mask has a permissible manufacturing error 2.14 times as large as a Ge-material phase mask. By constructing and solving an optimization problem, the ZnSe-material phase mask is optimally designed. The optimal phase mask is manufactured and measured with a form manufacturing error of 1.370 μm and a surface roughness value of 9.926 nm. Experiments prove that the wavefront coding athermalized longwave infrared (LWIR) imaging system works well over the temperature range from -40°C to +60°C. © 2016 Optical Society of America. (15 refs.)Main Heading: Optical designControlled terms: Germanium - Imaging systems - Infrared imaging - Infrared radiation - Manufacture - Optimization - Surface roughness - Thermography (imaging)Uncontrolled terms: Athermalization - Longwave infrared - Manufacturing errors - Optimization problems - Performance validation - Phase masks - Temperature range - Wave-front codingClassification Code: 537.1 Heat Treatment ProcessesHeat Treatment Processes - 549.3 Nonferrous Metals and Alloys excluding Alkali and Alkaline Earth Metals Nonferrous Metals and Alloys excluding Alkali and Alkaline Earth Metals - 741.1 Light/OpticsLight/Optics - 742.1 PhotographyPhotography - 746 Imaging TechniquesImaging Techniques - 921.5 Optimization TechniquesOptimization Techniques - 931.2 Physical Properties of Gases, Liquids and SolidsPhysical Properties of Gases, Liquids and Solids
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


SERF: A Simple, Effective, Robust, and Fast Image Super-Resolver from Cascaded Linear Regression
Hu, Yanting1; Wang, Nannan2; Tao, Dacheng3; Gao, Xinbo1; Li, Xuelong4 Source: IEEE Transactions on Image Processing, v 25, n 9, p 4091-4102, September 2016
; ISSN: 10577149; DOI: 10.1109/TIP.2016.2580942; Article number: 7491236;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 State Key Laboratory of Integrated Services Networks, School of Electronic Engineering, Xidian University, Xi'an; 710071, China2 State Key Laboratory of Integrated Services Networks, School of Telecommunications Engineering, Xidian University, Xi'an; 710071, China3 Centre for Quantum Computation and Intelligent Systems, Faculty of Engineering and Information Technology, University of Technology Sydney, Ultimo; NSW; 2007, Australia4 State Key Laboratory of Transient Optics and Photonics, Center for Optical Imagery Analysis and Learning, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China
Abstract: Example learning-based image super-resolution techniques estimate a high-resolution image from a low-resolution input image by relying on high- and low-resolution image pairs. An important issue for these techniques is how to model the relationship between high- and low-resolution image patches: most existing complex models either generalize hard to diverse natural images or require a lot of time for model training, while simple models have limited representation capability. In this paper, we propose a simple, effective, robust, and fast (SERF) image super-resolver for image super-resolution. The proposed super-resolver is based on a series of linear least squares functions, namely, cascaded linear regression. It has few parameters to control the model and is thus able to robustly adapt to different image data sets and experimental settings. The linear least square functions lead to closed form solutions and therefore achieve computationally efficient implementations. To effectively decrease these gaps, we group image patches into clusters via k-means algorithm and learn a linear regressor for each cluster at each iteration. The cascaded learning process gradually decreases the gap of high-frequency detail between the estimated high-resolution image patch and the ground truth image patch and simultaneously obtains the linear regression parameters. Experimental results show that the proposed method achieves superior performance with lower time consumption than the state-of-the-art methods. © 2016 IEEE. (52 refs.)Main Heading: Iterative methodsControlled terms: Channel capacity - Linear regression - Optical resolving power - Regression analysis - Surface reconstructionUncontrolled terms: Closed form solutions - Computationally efficient - example learning based - High resolution image - Image super resolutions - K-means - Linear regression parameters - State-of-the-art methodsClassification Code: 716.1 Information Theory and Signal ProcessingInformation Theory and Signal Processing - 741.1 Light/OpticsLight/Optics - 921.6 Numerical MethodsNumerical Methods - 922.2 Mathematical StatisticsMathematical Statistics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


A design of driving circuit for star sensor imaging camera
Li, Da-Wei1; Yang, Xiao-Xu1; Han, Jun-Feng1; Liu, Zhao-Hui1 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 9796, 2016, Selected Papers of the Photoelectronic Technology Committee Conferences held November 2015
; ISSN: 0277786X, E-ISSN: 1996756X; ISBN-13: 9781628418811; DOI: 10.1117/12.2228887; Article number: 97961Q; Conference: International Symposia on Atmosphere Optics and Adaptive Optics, Testing and Driving of Laser Fusion Energy Technology, High-performance Special Optical Film Technology, Novel Navigation Technology, Monitoring, Early Warning, Removal Technology of Space Targets and Debris, and UAV Payload Technology, November 15, 2015 - November 28, 2015; Sponsor: Chinese Academy of Engineering; Chinese Society for Optical Engineering; National Natural Science Foundation of China;
Publisher: SPIEAuthor affiliation: 1 Xi'an Institute of Optics and Precision Mechanics, CAS, Xi'an; 710119, China
Abstract: The star sensor is a high-precision attitude sensitive measuring instruments, which determine spacecraft attitude by detecting different positions on the celestial sphere. Imaging camera is an important portion of star sensor. The purpose of this study is to design a driving circuit based on Kodak CCD sensor. The design of driving circuit based on Kodak KAI-04022 is discussed, and the timing of this CCD sensor is analyzed. By the driving circuit testing laboratory and imaging experiments, it is found that the driving circuits can meet the requirements of Kodak CCD sensor. © 2016 SPIE. (4 refs.)Main Heading: Electric network analysisControlled terms: Adaptive optics - Cameras - Charge coupled devices - Laboratories - Reconfigurable hardware - Space debris - Stars - Timing circuits - Tracking (position)Uncontrolled terms: Celestial sphere - cut off - Driving circuits - High-precision - Imaging experiments - Sensitive measuring - Spacecraft attitude - timingClassification Code: 656.1 Space FlightSpace Flight - 657.2 Extraterrestrial Physics and Stellar PhenomenaExtraterrestrial Physics and Stellar Phenomena - 703.1.1 Electric Network AnalysisElectric Network Analysis - 713.4 Pulse CircuitsPulse Circuits - 714.2 Semiconductor Devices and Integrated CircuitsSemiconductor Devices and Integrated Circuits - 721.3 Computer CircuitsComputer Circuits - 741.1 Light/OpticsLight/Optics - 742.2 Photographic EquipmentPhotographic Equipment
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Bandwidth-tunable dissipative soliton and noise-like pulse in a normal dispersion fiber laser with a dual-scale saturable absorber
Cui, Yudong1, 2, 3 Source: Journal of Optics (United Kingdom), v 18, n 10, October 2016
; ISSN: 20408978, E-ISSN: 20408986; DOI: 10.1088/2040-8978/18/10/105503; Article number: 105503;
Publisher: Institute of Physics PublishingAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China2 State Key Laboratory of Modern Optical Instrumentation, Department of Optical Engineering, Zhejiang University, Hangzhou; 310027, China3 University of Chinese Academy of Sciences, Beijing; 100039, China
Abstract: A bandwidth-tunable dissipative soliton (DS) and noise-like pulse are demonstrated in an all-fiber normal dispersion fiber laser by employing a novel spectral filtering scheme. The mode locker is fabricated with a mixture composite that combines the merits of graphene and carbon nanotubes. At a pump power of 39 mW, a DS with knife edges is generated at 1565 nm. One of the steep edges is induced by gain spectral filtering and another is cut by a chirped fiber Bragg grating (CFBG). With higher pump power, the noise-like pulse operation displays an asymmetric spectral profile, confirming the novel combined spectral filtering. When the CFBG is stretched mechanically, the bandwidth of the DS and noise-like pulse can be tuned. The bandwidth-tunable mode-locked fiber laser has numerous potential applications, such as pulse shaping, as an amplifier and in optical nonlinear investigations. © 2016 IOP Publishing Ltd. (56 refs.)Main Heading: Fiber amplifiersControlled terms: Bandwidth - Carbon - Carbon nanotubes - Fiber Bragg gratings - Fiber lasers - Fibers - Laser mode locking - Locks (fasteners) - Mode-locked fiber lasers - Nanotubes - Optical pumping - Pulse shaping - Saturable absorbers - Solitons - YarnUncontrolled terms: Chirped fiber Bragg grating - Dissipative solitons - grapheme - Normal dispersion - Optical nonlinear - Optical soliton - Spectral filtering - Spectral profileClassification Code: 713.4 Pulse CircuitsPulse Circuits - 716.1 Information Theory and Signal ProcessingInformation Theory and Signal Processing - 744.1 Lasers, GeneralLasers, General - 744.4 Solid State LasersSolid State Lasers - 761 NanotechnologyNanotechnology - 804 Chemical Products GenerallyChemical Products Generally - 819.4 Fiber ProductsFiber Products
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Preface
Tan, Tieniu1; Li, Xuelong2; Chen, Xilin1; Zhou, Jie3; Yang, Jian4; Cheng, Hong5 Source: Communications in Computer and Information Science, v 663, p V, 2016, Pattern Recognition - 7th Chinese Conference, CCPR 2016, Proceedings
; ISSN: 18650929; ISBN-13: 9789811030048;
Publisher: Springer VerlagAuthor affiliation: 1 Chinese Academy of Sciences, Institute of Automation, Beijing, China2 Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, China3 Tsinghua University, Beijing, China4 Nanjing University of Science and Technology, Nanjing, China5 University of Electronic Science and Technology, Chengdu; Sichuan, China
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Deep Learning for Hyperspectral Data Classification through Exponential Momentum Deep Convolution Neural Networks
Yue, Qi1, 2, 3; Ma, Caiwen1 Source: Journal of Sensors, v 2016, 2016
; ISSN: 1687725X, E-ISSN: 16877268; DOI: 10.1155/2016/3150632; Article number: 3150632;
Publisher: Hindawi Publishing CorporationAuthor affiliation: 1 Xi'An Institute of Optics and Precision Mechanics, CAS, Xi'an; 710119, China2 University of Chinese Academy of Sciences, Beijing; 100039, China3 Xi'An University of Posts and Telecommunications, Xi'an; 710121, China
Abstract: Classification is a hot topic in hyperspectral remote sensing community. In the last decades, numerous efforts have been concentrated on the classification problem. Most of the existing studies and research efforts are following the conventional pattern recognition paradigm, which is based on complex handcrafted features. However, it is rarely known which features are important for the problem. In this paper, a new classification skeleton based on deep machine learning is proposed for hyperspectral data. The proposed classification framework, which is composed of exponential momentum deep convolution neural network and support vector machine (SVM), can hierarchically construct high-level spectral-spatial features in an automated way. Experimental results and quantitative validation on widely used datasets showcase the potential of the developed approach for accurate hyperspectral data classification. © 2016 Qi Yue and Caiwen Ma. (34 refs.)Main Heading: Classification (of information)Controlled terms: Artificial intelligence - Complex networks - Convolution - Learning systems - Pattern recognition - Remote sensing - Support vector machinesUncontrolled terms: Classification framework - Convolution neural network - Hyperspectral Data - Hyperspectral data classification - Hyperspectral remote sensing - Quantitative validation - Research efforts - Spatial featuresClassification Code: 716.1 Information Theory and Signal ProcessingInformation Theory and Signal Processing - 722 Computer Systems and EquipmentComputer Systems and Equipment - 723 Computer Software, Data Handling and ApplicationsComputer Software, Data Handling and Applications - 723.4 Artificial IntelligenceArtificial Intelligence
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Pressure sensor based on the Sagnac effect and fiber loop ringdown spectroscopy
Yang, Songlin1, 2; Ruan, Chi1; Wang, Yuntao1 Source: Optical Engineering, v 55, n 10, October 1, 2016
; ISSN: 00913286, E-ISSN: 15602303; DOI: 10.1117/1.OE.55.10.107101; Article number: 107101;
Publisher: SPIEAuthor affiliation: 1 Xian Institute of Optics, State Key Laboratory of Transient Optics and Photonic, No. 17 Xinxi Road, Xian; 710119, China2 University of Chinese Academy of Sciences, 19 A Yuquan Road, Beijing; 100049, China
Abstract: A fiber-optic sensing scheme of measuring pressure is described here. The high reflective mirror in a laser cavity is replaced by a Sagnac loop in this scheme. The method combining the Sagnac effect with fiber loop ringdown technology fully embodies the advantages of both. The working principle is discussed in detail, and the whole sensing performance is demonstrated by applying sensing force to the sensor area. The sensing force can be obtained by measuring the ringdown time. The pressure measurement range of this device is 40 to 350 N. The detection sensitivity 0.4 ns/N can be realized in this system. The experimental curve reveals a close relationship between the sensing strain and the ringdown time. © 2016 Society of Photo-Optical Instrumentation Engineers (SPIE). (21 refs.)Main Heading: Pressure effectsControlled terms: Fiber optic sensors - Fibers - Laser mirrors - Pressure sensorsUncontrolled terms: Detection sensitivity - Experimental curves - Fiber loop ringdown - Fiber pressure sensor - Fiber-optic sensing - High-reflective mirrors - Sagnac effect - Sensing performanceClassification Code: 741.1.2 Fiber OpticsFiber Optics - 741.3 Optical Devices and SystemsOptical Devices and Systems - 931.1 MechanicsMechanics - 944.3 Pressure Measuring InstrumentsPressure Measuring Instruments
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Improvement of CO2capture performance of calcium-based absorbent modified with palygorskite
Shan, Liyuan1; Li, Hui1, 2; Meng, Binglu3; Yu, Youhai3; Min, Yonggang1, 2 Source: Chinese Journal of Chemical Engineering, v 24, n 9, p 1283-1289, September 1, 2016
; ISSN: 10049541; DOI: 10.1016/j.cjche.2016.05.021;
Publisher: Chemical Industry PressAuthor affiliation: 1 College of Material and Mineral Resource, Xi'an University of Architecture and Technology, Xi'an; 710055, China2 Shaanxi Techno-Institute of Recycling Economy, Xi'an; 710055, China3 Xi'an Institute of Optics and Precision Mechanics of Chinese Academy of Science, Xi'an; 710119, China
Abstract: Limestone can be used for CO2capture and sequestration (CCS) in flue gas effectively. However, its CCS capability will dramatically decline after several cycles due to the surface “sintering”. In this work, the limestone was modified with palygorskite to reduce sintering phenomenon between the absorbent particles during the CCS process and the carbonation rate of the limestone can be enhanced effectively. Palygorskite is a natural mineral with nano-fibrous structure which can reduce the mutual contact of limestone particles during the CCS process. The results were detected by TGA, SEM, MIP, FTIR and particle size analyzer respectively. The best CO2capture performance of modified absorbent was 13.11% improvement with only 5 wt% palygorskite added during the CCS process after 15 cycles compared with natural absorbent. It was found that excellent microscopic structures of absorbent modified with palygorskite was created, and the surface sintering was postponed leading to CO2capture performance enhanced under the same conditions. © 2016 Elsevier B.V. (34 refs.)Main Heading: Carbon dioxideControlled terms: Absorption - Carbon capture - Limestone - Particle size - Particle size analysis - SinteringUncontrolled terms: Limestone particles - Microscopic structures - Nano-fibrous - Natural absorbents - Natural minerals - Palygorskites - Particle size analyzers - Sintering phenomenonClassification Code: 454 Environmental EngineeringEnvironmental Engineering - 802.3 Chemical OperationsChemical Operations - 804.2 Inorganic CompoundsInorganic Compounds - 951 Materials ScienceMaterials Science
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Trunk wormhole detection using bio-impedance spectroscopy measurements: A feasibility study
Wang, Wei1; Zhang, Xiongxing1; Wang, Kening1; Yang, Yuxiang2 Source: International Journal of Simulation: Systems, Science and Technology, v 17, n 27, p 23.1-23.6, 2016
; ISSN: 14738031, E-ISSN: 1473804X; DOI: 10.5013/IJSSST.a.17.27.23;
Publisher: UK Simulation SocietyAuthor affiliation: 1 School of Optoelectronic Engineering, Xi’an Technological University, Xi’an, China2 Department of Precision Instrumentation Engineering, Xi’an University of Technology, Xi’an, China
Abstract: Stem-Boring Pest (SBP) cause the most prevalent problem that harms the health of trees. Traditional SBP prevention uses manual survey of wormholes and is a time-consuming process. This paper proposes a novel Trunk Wormhole Detection (TWD) method based on Bio-Impedance Spectroscopy (BIS) measurements. A horizontal and a vertical trunk wormhole phantoms are prepared, and comparative BIS measurements under the situations without and with holes are performed using a precision impedance analyzers WK6500B. Remarkable differences both on impedance amplitudes and phases have been found before and after the holes formed in the phantoms. The Cole model parameter analysis finds that the Cole parameter R∞ decreases by 43.82% in the horizontal phantom, and decreases by 63.13% in the vertical phantoms, which suggests that R∞ may be an efficient indicator to detect trunk wormholes. © 2016, UK Simulation Society. All rights reserved. (18 refs.)Main Heading: SpectroscopyControlled terms: Computer simulationUncontrolled terms: Bio-Impedance spectroscopies - Feasibility studies - Impedance analyzer - Model parameters - nocv1 - Trunk wormhole - Wormhole detectionsClassification Code: 723.5 Computer ApplicationsComputer Applications
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Threshold characteristics analysis of dual-end-pumped Nd3+-doped gain-guided and index-antiguided fiber lasers
Shen, Xiao1, 2; Wei, Wei1 Source: MATEC Web of Conferences, v 61, June 28, 2016, International Seminar on Applied Physics, Optoelectronics and Photonics, APOP 2016; E-ISSN: 2261236X; DOI: 10.1051/matecconf/20166106011; Article number: 06011; Conference: International Seminar on Applied Physics, Optoelectronics and Photonics, APOP 2016, May 28, 2016 - May 29, 2016;
Publisher: EDP SciencesAuthor affiliation: 1 College of Optoelectronic Engineering, Nanjing University of Posts and Telecommunications, Nanjing; 210023, China2 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, Shanxi; 710119, China
Abstract: An analytical model for dual-end-pumped Nd3+-doped gain-guided and index-antiguided (GG-IAG) fiber laser is established. The corresponding analytical expression of the threshold pump power is obtained by solving the improved rate equations. Pump light propagation and threshold characteristics are both researched. Simulation results show that there are optimum values of N, a and L for the lowest Pth. When a=50μm, L=9cm, N=1.8∗1020cm-3, R1s=1, R2s=0.75, the lowest threshold pump power Pthof the GG-IAG fiber laser is about 11.95W, the results of the work may be helpful for the later experiments. © 2016 The Authors, published by EDP Sciences. (12 refs.)Main Heading: Pumping (laser)Controlled terms: Fiber lasersUncontrolled terms: Analytical expressions - End-pumped - Gain guided - Index antiguided - Optimum value - Rate equations - Threshold characteristics - Threshold pump powerClassification Code: 744.1 Lasers, GeneralLasers, General - 744.4 Solid State LasersSolid State Lasers
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Graphene-induced unique polarization tuning properties of excessively tilted fiber grating
Jiang, Biqiang1, 2; Yin, Guolu2; Zhou, Kaiming2, 3; Wang, Changle2; Gan, Xuetao1; Zhao, Jianlin1; Zhang, Lin2 Source: Optics Letters, v 41, n 23, p 5450-5453, December 1, 2016
; ISSN: 01469592, E-ISSN: 15394794; DOI: 10.1364/OL.41.005450;
Publisher: OSA - The Optical SocietyAuthor affiliation: 1 Key Laboratory of Space Applied Physics and Chemistry, Ministry of Education, Shaanxi Key Laboratory of Optical Information Technology, School of Science, Northwestern Polytechnical University, Xi'an; 710072, China2 Aston Institute of Photonic Technologies, Aston University, Birmingham; B4 7ET, United Kingdom3 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China
Abstract: By exploiting the polarization-sensitive coupling effect of graphene with the optical mode, we investigate the polarization modulation properties of a hybrid waveguide of graphene-integrated excessively tilted fiber grating (Ex-TFG). The theoretical analysis and experimental results demonstrate that the real and imaginary parts of complex refractive index of fewlayer graphene exhibit different effects on transverse electric (TE) and transverse magnetic (TM) cladding modes of the Ex-TFG, enabling stronger absorption in the TE mode and more wavelength shift in the TM mode. Furthermore, the surrounding refractive index can modulate the complex optical constant of graphene and then the polarization properties of the hybrid waveguide, such as resonant wavelength and peak intensity. Therefore, the unique polarization tuning property induced by the integration of the graphene layer with Ex-TFG may endow potential applications in all-in-one fiber modulators, fiber lasers, and biochemical sensors. © 2016 Optical Society of America. (20 refs.)Main Heading: Optical fiber couplingControlled terms: Fiber lasers - Fibers - Graphene - Polarization - Refractive index - Tuning - WaveguidesUncontrolled terms: Complex refractive index - Polarization modulation - Polarization properties - Polarization sensitive - Resonant wavelengths - Surrounding refractive indices (SRI) - Tilted fiber gratings - Transverse electricsClassification Code: 714.3 WaveguidesWaveguides - 741.1 Light/OpticsLight/Optics - 741.1.2 Fiber OpticsFiber Optics - 744.4 Solid State LasersSolid State Lasers - 761 NanotechnologyNanotechnology - 804 Chemical Products GenerallyChemical Products Generally
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


The estimation method on diffusion spot energy concentration of the detection system
Gao, Wei1; Song, Zongxi1; Liu, Feng1; Dan, Lijun1; Sun, Zhonghan1; Du, Yunfei1 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 9684, 2016, 8th International Symposium on Advanced Optical Manufacturing and Testing Technology: Optical Test, Measurement Technology, and Equipment
; ISSN: 0277786X, E-ISSN: 1996756X; ISBN-13: 9781628419191; DOI: 10.1117/12.2242811; Article number: 968421; Conference: 8th International Symposium on Advanced Optical Manufacturing and Testing Technology: Optical Test, Measurement Technology, and Equipment, AOMATT 2016, April 26, 2016 - April 29, 2016; Sponsor: Chinese Academy of Sciences, Institute of Optics and Electronics (IOE); The Chinese Optical Society (COS);
Publisher: SPIEAuthor affiliation: 1 Xi'An Institute of Optics and Precision Mechanics of Chinese Academy of Sciences, Xi'an, China
Abstract: We propose a method to estimate the diffusion spot energy of the detection system. We do outdoor observation experiments in Xinglong Observatory, by using a detection system which diffusion spot energy concentration is estimated (the correlation coefficient is approximate 0.9926).The aperture of system is 300mm and limiting magnitude of system is 14.15Mv. Observation experiments show that the highest detecting magnitude of estimated system is 13.96Mv, and the average detecting magnitude of estimated system is about 13.5Mv. The results indicate that this method can be used to evaluate the energy diffusion spot concentration level of detection system efficiently. © 2016 SPIE. (10 refs.)Main Heading: DiffusionControlled terms: Concentration (process) - Manufacture - Optical testingUncontrolled terms: Correlation coefficient - Detection system - Energy concentration - Energy diffusion - Estimate - Estimation methods - Nyquist frequency - Spot concentrationClassification Code: 537.1 Heat Treatment ProcessesHeat Treatment Processes - 741.3 Optical Devices and SystemsOptical Devices and Systems
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Design, fabrication, and testing of duralumin zoom mirror with variable thickness
Hui, Zhao1; Xie, Xiaopeng1, 2; Xu, Liang1; Ding, Jiaoteng1; Shen, Le1; Liu, Meiying1; Gong, Jie3 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 10154, 2016, Advanced Optical Design and Manufacturing Technology and Astronomical Telescopes and Instrumentation
; ISSN: 0277786X, E-ISSN: 1996756X; DOI: 10.1117/12.2243992; Article number: 1015409; Conference: International Symposium on Advanced Optical Design and Manufacturing Technologies and International Symposium on Astronomical Telescope and Instrumentation, May 9, 2016 - May 11, 2016; Sponsor: China High-Tech Industrialization Association (CHIA); Chinese Society for Optical Engineering (CSOE);
Publisher: SPIEAuthor affiliation: 1 Xi'an Institute of Optics and Precision Mechanics, CAS, Xi'an; 710119, China2 Graduate School of University of Chinese Academy of Science, Beijing; 100047, China3 Xi'an BoYa Precision Optics Co.Ltd Company, China
Abstract: Zoom mirror is a kind of active optical component that can change its curvature radius dynamically. Normally, zoom mirror is used to correct the defocus and spherical aberration caused by thermal lens effect to improve the beam quality of high power solid-state laser since that component was invented. Recently, the probable application of zoom mirror in realizing non-moving element optical zoom imaging in visible band has been paid much attention. With the help of optical leveraging effect, the slightly changed local optical power caused by curvature variation of zoom mirror could be amplified to generate a great alteration of system focal length without moving elements involved in, but in this application the shorter working wavelength and higher surface figure accuracy requirement make the design and fabrication of such a zoom mirror more difficult. Therefore, the key to realize non-moving element optical zoom imaging in visible band lies in zoom mirror which could provide a large enough saggitus variation while still maintaining a high enough surface figure. Although the annular force based actuation could deform a super-Thin mirror having a constant thickness to generate curvature variation, it is quite difficult to maintain a high enough surface figure accuracy and this phenomenon becomes even worse when the diameter and the radius-Thickness ratio become bigger. In this manuscript, by combing the pressurization based actuation with a variable thickness mirror design, the purpose of obtaining large saggitus variation and maintaining quite good surface figure accuracy at the same time could be achieved. A prototype zoom mirror with diameter of 120mm and central thickness of 8mm is designed, fabricated and tested. Experimental results demonstrate that the zoom mirror having an initial surface figure accuracy superior to 1/50λ could provide at least 21um saggitus variation and after finishing the curvature variation its surface figure accuracy could still be superior to 1/20λ, which proves that the effectiveness of the theoretical design. © 2016 SPIE. (20 refs.)Main Heading: Laser mirrorsControlled terms: Boundary integral equations - Fabrication - Manufacture - Mirrors - Optical design - Optical testing - Pressurization - Radio telescopes - Solid state lasers - Telescopes - Thickness controlUncontrolled terms: High power solid-state lasers - Optical zooming - Radius thickness ratios - Saggitus Variation - Spherical aberrations - Surface figure accuracies - Thermal lens effects - Variable thicknessClassification Code: 537.1 Heat Treatment ProcessesHeat Treatment Processes - 657.2 Extraterrestrial Physics and Stellar PhenomenaExtraterrestrial Physics and Stellar Phenomena - 731.3 Specific Variables ControlSpecific Variables Control - 741.1 Light/OpticsLight/Optics - 741.3 Optical Devices and SystemsOptical Devices and Systems - 744.4 Solid State LasersSolid State Lasers - 921.2 CalculusCalculus
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Pressure sensor for Weight-In-Motion measurement based on fiber loop ring-down spectroscopy
Yang, Songlin1, 2; Ruan, Chi1; Wang, Yuntao1 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 10158, 2016, Optical Communication and Optical Fiber Sensors and Optical Memories for Big Data Storage
; ISSN: 0277786X, E-ISSN: 1996756X; ISBN-13: 9781510607743; DOI: 10.1117/12.2246819; Article number: 101580U; Conference: International Symposium on Optical Communication and Optical Fiber Sensors and the International Symposium on Optical Memories for Big Data Storage, May 9, 2016 - May 11, 2016; Sponsor: China High-Tech Industrialization Association (CHIA); Chinese Society for Optical Engineering (CSOE);
Publisher: SPIEAuthor affiliation: 1 Xi'an Institute of Optics and Precision Mechanics, CAS, Xi'an; 710119, China2 University of Chinese Academy of Sciences, Beijing; 100039, China
Abstract: In order to resolve the disturbance of external perturbation in Weight-In-Motion (WIM) measurement by traditional methods, a novel pressure sensor for WIM of vehicles based on fiber ring-down spectroscopy is proposed here. A micro-bending sensing head is designed and its working principle is discussed in this paper. The fiber loop ring-down (FLRD) system reveals that the sensing forces applied to the sensing head can be obtained by measuring the ring-down time. Meanwhile, the velocity of vehicles is measured by analyzing two ring-down spectrums in this scheme. Experiment results show that the precision of velocity of vehicles is good and the sensor has a linear response to the applied force. © 2016 SPIE. (5 refs.)Main Heading: Optical fiber communicationControlled terms: Band structure - Big data - Data storage equipment - Digital storage - Fiber optic sensors - Fibers - Optical communication - Optical data storage - Optical fibers - Pressure sensors - Vehicles - Velocity - Weigh-in-motion (WIM)Uncontrolled terms: Applied forces - External perturbations - Linear response - Micro-bending - Ring down time - Ringdown spectroscopy - Sensing force - Weight in motionsClassification Code: 717.1 Optical Communication SystemsOptical Communication Systems - 722.1 Data Storage, Equipment and TechniquesData Storage, Equipment and Techniques - 723.2 Data Processing and Image ProcessingData Processing and Image Processing - 741.1.2 Fiber OpticsFiber Optics - 933 Solid State PhysicsSolid State Physics - 943.3 Special Purpose InstrumentsSpecial Purpose Instruments - 944.3 Pressure Measuring InstrumentsPressure Measuring Instruments
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Gestalt principle based change detection and background reconstruction
Qiu, Shi1; Dong, Yongsheng1; Lu, Xiaoqiang1; Du, Ming2, 3 Source: Communications in Computer and Information Science, v 664 CCIS, p 20-29, 2016, Intelligent Visual Surveillance - 4th Chinese Conference, IVS 2016, Proceedings
; ISSN: 18650929; ISBN-13: 9789811034756; DOI: 10.1007/978-981-10-3476-3_3; Conference: 4th Chinese Conference on Intelligent Visual Surveillance, IVS 2016, October 19, 2016 - October 19, 2016; Sponsor: Center for Research on Intelligent Perception and Computing; Institute of Automation;
Publisher: Springer VerlagAuthor affiliation: 1 Center for OPTical IMagery Analysis and Learning (OPTIMAL), State Key Laboratory of Transient Optics and Photonics, Xi’an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi’an, China2 College of Physics and Information Engineering, Fuzhou University, Fuzhou, China3 Fujian Key Lab of Medical Instrument and Pharmaceutical Technology, Fuzhou, China
Abstract: Gaussian mixture model based detection algorithms can easily lead to fragmentary due to the fixed number of Gaussian components. In this paper, we propose a gestalt principle based change target extraction method, and further present a background reconstruction algorithm. In particular, firstly we applied the Gaussian mixture model to extract the moving target as others did but this may lead to incomplete extraction. Secondly, we have also tried to apply the frame difference method to extract the moving target more precisely. Finally, we determine to build a static background according to relationships between each frame of a moving target. Experiment results reveal that the proposed detection method outperforms the other three representative detection methods. Moreover, our background reconstruction algorithm is also proved to be very effective and robust in reconstructing the backgrounds of a video. © Springer Nature Singapore Pte Ltd. 2016. (14 refs.)Main Heading: Object recognitionControlled terms: Chemical detection - Extraction - Gaussian distribution - Image segmentation - Monitoring - Security systems - Signal detectionUncontrolled terms: Background reconstruction - Detection algorithm - Frame difference methods - Gaussian components - Gaussian Mixture Model - Gestalt visual principle - Moving targets - Video surveillanceClassification Code: 716.1 Information Theory and Signal ProcessingInformation Theory and Signal Processing - 801 ChemistryChemistry - 802.3 Chemical OperationsChemical Operations - 914.1 Accidents and Accident PreventionAccidents and Accident Prevention - 922.1 Probability TheoryProbability Theory
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


A novel method to real-time offset correction for frame transfer CCD
Chen, Zhi1; Wen, Yan1; Yao, Dalei1; Jiang, Baotan1 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 9686, 2016, 8th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optoelectronic Materials and Devices
; ISSN: 0277786X, E-ISSN: 1996756X; ISBN-13: 9781628419214; DOI: 10.1117/12.2242264; Article number: 96861L; Conference: 8th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optoelectronic Materials and Devices, AOMATT 2016, April 26, 2016 - April 29, 2016; Sponsor: Chinese Academy of Sciences, Institute of Optics and Electronics (IOE); The Chinese Optical Society (COS);
Publisher: SPIEAuthor affiliation: 1 Xi'An Institute of Optics and Precision Mechanics of CAS, Xi'an; 710119, China
Abstract: The traditional CCD offset correction processing method is to obtain normal exposure image and dark field image respectively. In the later image processing, use normal exposure image minus the dark field image. Although traditional method can offset correction, but cannot to realize real-time offset correction. Because the traditional method is to obtain offset correction after acquire normal exposure image and dark field image, while the normal exposure image and dark field image is not acquired at the same time. This method would reduce the offset correction precision. A novel method to real-time offset correction for frame transfer CCD is proposed in this paper. The method is based on the improvement of the traditional frame transfer CCD driving timing and CCD signal processing sequence. The traditional frame transfer CCD driving timing is exposure, frame transfer and read CCD level shift register. An offset correction line is added before read CCD data storage area to acquire the offset variation of the each frame image. Take it as a normal image data. In CCD signal processing algorithm to offset calculation and correction. This novel method can correct the offset of each frame image each pixel data real time. In this way the effect on the images from the variation of the offset caused by factors such as the working temperature and the aging of electronic devices in CCD signal processing circuit of CCD camera is restrained. © 2016 SPIE. (6 refs.)Main Heading: Image processingControlled terms: CCD cameras - Charge coupled devices - Digital storage - Image acquisition - Manufacture - Materials testing - Optical data processing - Optoelectronic devices - Processing - Shift registers - Signal processingUncontrolled terms: Driving timing - Frame transfer CCD - Offset corrections - Processing method - Real time - Signal processing algorithms - Signal processing circuits - Working temperaturesClassification Code: 714.2 Semiconductor Devices and Integrated CircuitsSemiconductor Devices and Integrated Circuits - 716.1 Information Theory and Signal ProcessingInformation Theory and Signal Processing - 721.3 Computer CircuitsComputer Circuits - 722.1 Data Storage, Equipment and TechniquesData Storage, Equipment and Techniques - 723 Computer Software, Data Handling and ApplicationsComputer Software, Data Handling and Applications - 723.2 Data Processing and Image ProcessingData Processing and Image Processing - 741.3 Optical Devices and SystemsOptical Devices and Systems - 913.4 ManufacturingManufacturing - 951 Materials ScienceMaterials Science
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


A 60GHz RoF(radio-over-fiber) transmission system based on PM modulator
Wang, Xin1, 2; Liu, Yi3; Wang, Wen-Ting2 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 10017, 2016, Semiconductor Lasers and Applications VII
; ISSN: 0277786X, E-ISSN: 1996756X; ISBN-13: 9781510604537; DOI: 10.1117/12.2246651; Article number: 100171B; Conference: Semiconductor Lasers and Applications VII, October 12, 2016 - October 14, 2016; Sponsor: Chinese Optical Society (COS); The Society of Photo-Optical Instrumentation Engineers (SPIE);
Publisher: SPIEAuthor affiliation: 1 Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, No. 17, Xinxi Road, Xi'an; 710119, China2 Institute of Semiconductors, Chinese Academy of Sciences, No. 35, Tsinghua East Road, Beijing; 100083, China3 Hunan University, Changsha, Hunan; 410082, China
Abstract: As one of the most important applications of microwave photonic, ROF (Radio over Fiber) system, which combines the advantages of optical communication and wireless communication, is a good candidate for broadband mobile Communication In this paper, we built and simulation a 60GHz RoF(Radio-over-Fiber) transmission system based on PM modulator. First, we introduce the PM-IM(Phase modulation to intensity modulation) modulation mechanisms by the breaking the phase balanced approach. This method solves the problem that the constant envelope (phase modulation signal) generated by the phase modulator can not be directly detected by a photo detector. A standard single-mode fiber (SMF) is connected input to the F-P(Fabry-Perot) optical filter, which is to achieve the PM-IM modulation conversion by changing the wavelength of the laser or the frequency of the modulation factor of the F-P optical filter to adapt to different fiber lengths and the signal transmission rate. These two methods which changing the phase relationship between the optical carrier and the optical side band can realize the ideal phase transition to obtain efficient and low loss modulation conversion. Finally, the simulation results show that different fiber lengths and the signal transmission rate configuration of different wavelength of the laser or the frequency of the modulation factor of the F-P optical filter, the BER performance and the eye diagram of the 60GHz RoF transmission system signals have been improved based on these PM-IM modulation methods. © 2016 SPIE. (8 refs.)Main Heading: ModulationControlled terms: Dispersion (waves) - Fabry-Perot interferometers - Fibers - Light modulators - Millimeter waves - Optical communication - Optical fiber communication - Optical filters - Optical frequency conversion - Phase diagrams - Phase modulation - Radio transmission - Radio-over-fiber - Semiconductor lasers - Single mode fibers - Transmissions - Wireless telecommunication systemsUncontrolled terms: Broadband mobile communication - Intensity modulations - Microwave Photonics - Millimeter-wave communication - ROF system - Signal transmission rates - Standard single mode fibers - Wireless communicationsClassification Code: 602.2 Mechanical TransmissionsMechanical Transmissions - 711 Electromagnetic WavesElectromagnetic Waves - 716.3 Radio Systems and EquipmentRadio Systems and Equipment - 717.1 Optical Communication SystemsOptical Communication Systems - 741 Light, Optics and Optical DevicesLight, Optics and Optical Devices - 744.4.1 Semiconductor LasersSemiconductor Lasers - 941.3 Optical InstrumentsOptical Instruments
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Generation of an optical frequency comb in the green with silicon nitride microresonators
Volet, Nicolas1; Chang, Lin1; Wang, Leiran1, 2; Pfeiffer, Martin H. P.3; Zervas, Michael3; Guo, Hairun3; Kippenberg, Tobias J.3; Bowers, John E.1 Source: 2016 Conference on Lasers and Electro-Optics, CLEO 2016, December 16, 2016, 2016 Conference on Lasers and Electro-Optics, CLEO 2016; ISBN-13: 9781943580118; Article number: 7789186; Conference: 2016 Conference on Lasers and Electro-Optics, CLEO 2016, June 5, 2016 - June 10, 2016;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 Department of Electrical and Computer Engineering, University of California, Santa Barbara (UCSB), CA; 93106, United States2 State Key Laboratory of Transient Optics and Photonics, Xian Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xian; 710119, China3 EcolePolytechnique Federale de Lausanne (EPFL), 1015 Lausanne, Switzerland
Abstract: The first realization of a green-light frequency comb is reported in a silicon nitride ring microresonator, from third-order non-linear interaction of a near-infrared 1-THz spacing Kerr comb spanning 2/3 of an octave. © 2016 OSA. (12 refs.)
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Block Principal Component Analysis with Nongreedy &ell; 1 -Norm Maximization
Li, Bing Nan1; Yu, Qiang2; Wang, Rong2; Xiang, Kui3; Wang, Meng4; Li, Xuelong5 Source: IEEE Transactions on Cybernetics, v 46, n 11, p 2543-2547, November 2016
; ISSN: 21682267; DOI: 10.1109/TCYB.2015.2479645;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 Department of Biomedical Engineering, Hefei University of Technology, Hefei; 230009, China2 Xian Research Institute of Hi-Tech, Xian; 710025, China3 School of Automation, Wuhan University of Technology, Wuhan; 430070, China4 School of Computer Science and Information Engineering, Hefei University of Technology, Hefei; 230009, China5 Center for OPTical IMagery Analysis and Learning (OPTIMAL), State Key Laboratory of Transient Optics and Photonics, Xian Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xian; 710119, China
Abstract: Block principal component analysis with &ell;1-norm (BPCA-L1) has demonstrated its effectiveness in a lot of visual classification and data mining tasks. However, the greedy strategy for solving the &ell;1-norm maximization problem is prone to being struck in local solutions. In this paper, we propose a BPCA with nongreedy &ell;1-norm maximization, which obtains better solutions than BPCA-L1 with all the projection directions optimized simultaneously. Other than BPCA-L1, the new algorithm has been evaluated against some popular principal component analysis (PCA) algorithms including PCA-L1 and 2-D PCA-L1 on a variety of benchmark data sets. The results demonstrate the effectiveness of the proposed method. © 2013 IEEE. (21 refs.)Main Heading: Principal component analysisControlled terms: Data miningUncontrolled terms: block principal component analysis (BPCA) - Dimensionality reduction - Greedy strategies - Maximization problem - nongreedy strategy - outliers - Projection direction - Visual classificationClassification Code: 723.2 Data Processing and Image ProcessingData Processing and Image Processing - 922.2 Mathematical StatisticsMathematical Statistics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


New &ell;-1-norm relaxations and optimizations for graph clustering
Nie, Feiping1; Wang, Hua2; Deng, Cheng3; Gao, Xinbo3; Li, Xuelong4; Huang, Heng1 Source: 30th AAAI Conference on Artificial Intelligence, AAAI 2016, p 1962-1968, 2016, 30th AAAI Conference on Artificial Intelligence, AAAI 2016; ISBN-13: 9781577357605; Conference: 30th AAAI Conference on Artificial Intelligence, AAAI 2016, February 12, 2016 - February 17, 2016; Sponsor: Artificial Intelligence; Baidu; et al.; IBM; Infosys; NSF;
Publisher: AAAI pressAuthor affiliation: 1 Department of Computer Science and Engineering, University of Texas at Arlington, United States2 Department of Electrical Engineering and Computer Science, Colorado School of Mines, United States3 School of Electronic Engineering, Xidian University, Xi'an, China4 Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, China
Abstract: In recent data mining research, the graph clustering methods, such as normalized cut and ratio cut, have been well studied and applied to solve many unsupervised learning applications. The original graph clustering methods are NP-hard problems. Traditional approaches used spectral relaxation to solve the graph clustering problems. The main disadvantage of these approaches is that the obtained spectral solutions could severely deviate from the true solution. To solve this problem, in this paper, we propose a new relaxation mechanism for graph clustering methods. Instead of minimizing the squared distances of clustering results, we use the &ell;1-norm distance. More important, considering the normalized consistency, we also use the &ell;1- norm for the normalized terms in the new graph clustering relaxations. Due to the sparse result from the &ell;1-norm minimization, the solutions of our new relaxed graph clustering methods get discrete values with many zeros, which are close to the ideal solutions. Our new objectives are difficult to be optimized, because the minimization problem involves the ratio of nonsmooth terms. The existing sparse learning optimization algorithms cannot be applied to solve this problem. In this paper, we propose a new optimization algorithm to solve this difficult non-smooth ratio minimization problem. The extensive experiments have been performed on three two-way clustering and eight multi-way clustering benchmark data sets. All empirical results show that our new relaxation methods consistently enhance the normalized cut and ratio cut clustering results. © Copyright 2016, Association for the Advancement of Artificial Intelligence (www.aaai.org). All rights reserved. (25 refs.)Main Heading: Problem solvingControlled terms: Artificial intelligence - Cluster analysis - Clustering algorithms - Computational complexity - Data mining - OptimizationUncontrolled terms: 1-norm minimizations - Learning optimizations - Minimization problems - Optimization algorithms - Relaxation mechanism - Spectral relaxations - Spectral solutions - Traditional approachesClassification Code: 721.1 Computer Theory, Includes Formal Logic, Automata Theory, Switching Theory, Programming TheoryComputer Theory, Includes Formal Logic, Automata Theory, Switching Theory, Programming Theory - 723 Computer Software, Data Handling and ApplicationsComputer Software, Data Handling and Applications - 903.1 Information Sources and AnalysisInformation Sources and Analysis - 921.5 Optimization TechniquesOptimization Techniques
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Directly observing particle manipulations along light trajectories with axial plane optical microscopy
Peng, Tong1; An, Sha1; Zhou, Xing1; Han, Guoxia1; Huang, Zhangxiang1; Wang, Meirong2; Yao, Baoli1; Zhang, Peng1 Source: 2016 Conference on Lasers and Electro-Optics, CLEO 2016, December 16, 2016, 2016 Conference on Lasers and Electro-Optics, CLEO 2016; ISBN-13: 9781943580118; Article number: 7788366; Conference: 2016 Conference on Lasers and Electro-Optics, CLEO 2016, June 5, 2016 - June 10, 2016;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China2 Key Laboratory of Space Applied Physics and Chemistry, Ministry of Education, Shaanxi Key Laboratory of Optical Information Technology, School of Science, Northwestern Polytechnical University, Xi'an; 710129, China
Abstract: We demonstrate the direct observation of optical particle manipulations along light trajectories with the axial plane optical microscopy (APOM). Optically trapped particles moving along both straight and curved trajectories are successfully monitored by the APOM. © 2016 OSA. (12 refs.)
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Nanosecond passively mode-locked laser with a hundred megahertz spectral bandwidth
Kues, Michael1; Reimer, Christian1; Wetzel, Benjamin1, 2; Roztocki, Piotr1; Little, Brent E.3; Chu, Sai T.4; Moss, David J.1, 5; Morandotti, Roberto1 Source: Optics InfoBase Conference Papers, July 21, 2014, Frontiers in Optics, FiO 2016; ISBN-13: 9781943580194; DOI: 10.1364/FIO.2016.JTh2A.192; Conference: Frontiers in Optics, FiO 2016, October 17, 2016 - October 21, 2016; Sponsor: APS-American Physical Society; OSA-The Optical Society;
Publisher: OSA - The Optical SocietyAuthor affiliation: 1 INRS-EMT, 1650 Boulevard Lionel-Boulet, Varennes; QC; J3X 1S2, Canada2 School of Mathematical and Physical Sciences, University of Sussex, Sussex House, Falmer, Brighton; BN1 9RH, United Kingdom3 Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Science, Xi'an, China4 City University of Hong Kong, Department of Physics and Materials Science, Tat Chee Avenue, Hong Kong, China5 Center for Micro-Photonics, Swinburne University of Technology, Hawthorn; VIC; 3122, Australia
Abstract: We demonstrate a passively mode-locked laser emitting 4.3 nanosecond quasi-Fourierlimited pulses with a record low (104.9 MHz) spectral bandwidth. The laser relies on the simultaneous nested-cavity filtering and cavity-enhanced nonlinear interactions within an integrated microring resonator. © OSA 2016. (11 refs.)Main Heading: Mode-locked fiber lasersControlled terms: Bandwidth - Lasers - Passive mode lockingUncontrolled terms: Microring resonator - Nonlinear interactions - Passively mode-locked lasers - Spectral bandwidthClassification Code: 716.1 Information Theory and Signal ProcessingInformation Theory and Signal Processing - 744.1 Lasers, GeneralLasers, General
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Four-photon entanglement generation with integrated optical frequency combs
Reimer, Christian1; Kues, Michael1; Roztocki, Piotr1; Caspani, Lucia1, 2; Bromberg, Yaron3; Wetzel, Benjamin1; Little, Brent E.4; Chu, Sai T.5; Moss, David J.1, 6; Morandotti, Roberto1 Source: Optics InfoBase Conference Papers, July 21, 2014, Integrated Photonics Research, Silicon and Nanophotonics, IPRSN 2016; ISBN-13: 9781943580149; Conference: Integrated Photonics Research, Silicon and Nanophotonics, IPRSN 2016, July 18, 2016 - July 20, 2016; Sponsor: AMERICAN ELEMENTS; NUFERN; OSA; Yenista Optics;
Publisher: OSA - The Optical SocietyAuthor affiliation: 1 INRS-EMT, 1650 Boulevard Lionel-Boulet, Varennes; QC; J3X 1S2, Canada2 School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh; EH14 4AS, United Kingdom3 Department of Applied Physics, Yale University, New Haven; CT; 06520, United States4 Xi'an Institute of Optics and Precision Mechanics of CAS, Xi'an, China5 Department of Physics and Material Science, City University of Hong Kong, Tat Chee Avenue, Hong Kong6 Centre for Micro Photonics, Swinburne University of Technology, Hawthorne; VIC; 3122, Australia
Abstract: We demonstrate the generation of four-photon entangled quantum states with integrated optical frequency comb sources. We measure four-photon quantum interference with a visibility above 89%, and perform quantum state tomography revealing a fidelity above 64%. © OSA 2016. (13 refs.)Main Heading: Quantum entanglementControlled terms: Nanophotonics - Natural frequencies - Optical materials - Photonics - Photons - Quantum optics - Quantum theoryUncontrolled terms: Four-photon entanglement - Optical frequency comb sources - Optical frequency combs - Quantum interference - Quantum state - Quantum state tomographyClassification Code: 741.1 Light/OpticsLight/Optics - 741.3 Optical Devices and SystemsOptical Devices and Systems - 931.3 Atomic and Molecular PhysicsAtomic and Molecular Physics - 931.4 Quantum Theory; Quantum MechanicsQuantum Theory; Quantum Mechanics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Real-time static polarimetric image dehazing technique based on atmospheric scattering correction
Xia, Pu1, 2; Liu, Xue-Bin1 Source: Beijing Youdian Daxue Xuebao/Journal of Beijing University of Posts and Telecommunications, v 39, n 6, p 33-36 and 71, December 1, 2016; Language: Chinese
; ISSN: 10075321; DOI: 10.13190/j.jbupt.2016.06.006;
Publisher: Beijing University of Posts and TelecommunicationsAuthor affiliation: 1 Key Laboratory of Spectral Imaging Technology, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China2 University of Chinese Academy of Sciences, Beijing; 100049, China
Abstract: In order to realize real-time static image recovery under hazy weather, a new theory of polarimetric dehazing was presented based on study of the atmospheric scattering model, analyzation on the effects of aerosols and the method of atmospheric scattering correction. The polarimetric information is obtained statically from the original images by Stokes equation and the Muller matrix. The sky region is extracted in real time based on the polarimetric measurement of the hole image. The influence of the range of polarization orientation angle and the threshold of air light intensity are analyzed based on the extraction result. The real time static polarimetric image dehazing method can be realized with fixed linear polarimetric images. No manual operation or subjective evaluation is needed which greatly simplifies the dehazing process. The accuracy of image recovery is increased by solving the problem of the estimation of the global parameters. The real time static polarimetric dehazing method provides a new theoretical and technical way for high-resolution, high stability and real-time image recovery under hazy weather. © 2016, Editorial Department of Journal of Beijing University of Posts and Telecommunications. All right reserved. (8 refs.)Main Heading: Image processingControlled terms: Aerosols - Atmospheric aerosols - Demulsification - Image analysis - Image reconstruction - Polarimeters - PolarizationUncontrolled terms: Atmospheric scattering - Atmospheric scattering models - Image defogging - Polarimetric informations - Polarimetric measurements - Polarization analysis - Polarization orientation angles - Subjective evaluationsClassification Code: 443.1 Atmospheric PropertiesAtmospheric Properties - 802.3 Chemical OperationsChemical Operations - 941.3 Optical InstrumentsOptical Instruments
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


MoS2-Mode-Locked Fiber Laser Delivering Ultrashort Pulses with Three Types of Sidebands
Lu, Feifei1; Liu, Xueming1; Yang, Huiran1 Source: Optics InfoBase Conference Papers, August 29, 2016, Nonlinear Photonics, NP 2016; ISBN-13: 9781943580170; Conference: Nonlinear Photonics, NP 2016, September 5, 2016 - September 8, 2016; Sponsor: American Elements; Australian Optical Society; cudos; Modular Photonics; OSA;
Publisher: OSA - The Optical SocietyAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China
Abstract: We demonstrate an erbium-doped fiber laser passively mode-locked by a monolayer MoS2which is covered onto a fiber taper. Three types of sidebands, e.g. peak, peakdip and dipspectral sidebands, are observed in the experiment. © 2016 OSA. (6 refs.)Main Heading: Mode-locked fiber lasersControlled terms: Fiber lasers - Molybdenum compounds - Passive mode locking - Ultrashort pulsesUncontrolled terms: Erbium doped fiber laser - Fiber taper - Passively mode-lockedClassification Code: 744.1 Lasers, GeneralLasers, General - 744.4 Solid State LasersSolid State Lasers
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Real time H.264 high definition videos encoding based on TMS320DM368 and a video quality evaluation framework
Hao, Fusheng1, 2; Huang, Jijiang2; Wei, Liu2; Wang, Yanan1, 2; Yang, Hongtao2; Cao, Jianzhong2 Source: Proceedings of 2016 IEEE Advanced Information Management, Communicates, Electronic and Automation Control Conference, IMCEC 2016, p 128-132, February 28, 2017, Proceedings of 2016 IEEE Advanced Information Management, Communicates, Electronic and Automation Control Conference, IMCEC 2016; ISBN-13: 9781467396127; DOI: 10.1109/IMCEC.2016.7867186; Article number: 7867186; Conference: 2016 IEEE Advanced Information Management, Communicates, Electronic and Automation Control Conference, IMCEC 2016, October 3, 2016 - October 5, 2016; Sponsor: Chongqing Global Union Academy of Science and Technology; Global Union Academy of Science and Technology; IEEE Beijing Section; Xi'an Peihua University;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 University of Chinese Academy of Sciences, Beijing, China2 Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, China
Abstract: This paper presents a framework for evaluating quality of video encoding algorithms. This technique works by collecting source videos, encoding the source videos with a given algorithm, and decoding the compressed sequences. The decoded video shall be measured with the original sources in a specific evaluation method and feedback to the algorithm. Under the guidance of this framework, an implementation based on embedded device is achieved. Firstly, we collect test source videos in two ways: the commonly used standard sequences and actual scenes captured by camera. Secondly, a popular video encoding standard, H.264, is realized on TMS320DM368, a digital media system-on-chip produced by TEXAS INSTRUMENTS (TI). Finally, peak signal-to-noise ratio (PSNR) is implemented and computed among different test sequences. In the experiments, we achieve the real time compression of high definition videos with an acceptable PSNR. The video quality framework also can be easily extended to other encoding algorithms. © 2016 IEEE. (12 refs.)Main Heading: Quality controlControlled terms: Decoding - Digital storage - Encoding (symbols) - Image coding - Information management - Network function virtualization - Signal to noise ratio - System-on-chip - Video camerasUncontrolled terms: Encoding algorithms - H.264 - High definition video - Peak signal to noise ratio - Real-time compression - Texas Instruments - TMS320DM368 - Video qualityClassification Code: 714.2 Semiconductor Devices and Integrated CircuitsSemiconductor Devices and Integrated Circuits - 716.1 Information Theory and Signal ProcessingInformation Theory and Signal Processing - 716.4 Television Systems and EquipmentTelevision Systems and Equipment - 722.1 Data Storage, Equipment and TechniquesData Storage, Equipment and Techniques - 723.2 Data Processing and Image ProcessingData Processing and Image Processing - 913.3 Quality Assurance and ControlQuality Assurance and Control
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Block-Row Sparse Multiview Multilabel Learning for Image Classification
Zhu, Xiaofeng1, 2; Li, Xuelong3; Zhang, Shichao4 Source: IEEE Transactions on Cybernetics, v 46, n 2, p 450-461, February 2016
; ISSN: 21682267; DOI: 10.1109/TCYB.2015.2403356; Article number: 7051274;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 School of Mathematics and Statistics, Xi'an Jiaotong University, Xi'an, China2 Guangxi Key Laboratory of Multi-source Information Mining and Security, Guangxi Normal University, Guilin, China3 Center for Optical Imagery Analysis and Learning, State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Xi'an, China4 School of Computer Science and Information Technology, Zhejiang Gongshang University, Hangzhou, China
Abstract: In image analysis, the images are often represented by multiple visual features (also known as multiview features), that aim to better interpret them for achieving remarkable performance of the learning. Since the processes of feature extraction on each view are separated, the multiple visual features of images may include overlap, noise, and redundancy. Thus, learning with all the derived views of the data could decrease the effectiveness. To address this, this paper simultaneously conducts a hierarchical feature selection and a multiview multilabel (MVML) learning for multiview image classification, via embedding a proposed a new block-row regularizer into the MVML framework. The block-row regularizer concatenating a Frobenius norm (F-norm) regularizer and an 2,1-norm regularizer is designed to conduct a hierarchical feature selection, in which the F-norm regularizer is used to conduct a high-level feature selection for selecting the informative views (i.e., discarding the uninformative views) and the 2,1-norm regularizer is then used to conduct a low-level feature selection on the informative views. The rationale of the use of a block-row regularizer is to avoid the issue of the over-fitting (via the block-row regularizer), to remove redundant views and to preserve the natural group structures of data (via the F-norm regularizer), and to remove noisy features (the 2,1-norm regularizer), respectively. We further devise a computationally efficient algorithm to optimize the derived objective function and also theoretically prove the convergence of the proposed optimization method. Finally, the results on real image datasets show that the proposed method outperforms two baseline algorithms and three state-of-The-Art algorithms in terms of classification performance. © 2013 IEEE. (66 refs.)Main Heading: Image classificationControlled terms: Algorithms - Classification (of information) - Feature extractionUncontrolled terms: Classification performance - Computationally efficient - Hierarchical features - Low-level feature selections - Multi-label learning - Multi-view image classifications - Optimization method - State-of-the-art algorithms
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Unsupervised Band Selection Based on Evolutionary Multiobjective Optimization for Hyperspectral Images
Gong, Maoguo1; Zhang, Mingyang1; Yuan, Yuan2 Source: IEEE Transactions on Geoscience and Remote Sensing, v 54, n 1, p 544-557, January 1, 2016
; ISSN: 01962892; DOI: 10.1109/TGRS.2015.2461653; Article number: 7214263;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 Ministry of Education, International Research, Center for Intelligent Perception and Computation, Xidian University, Xi'an, China2 Center for OPTical IMagery Analysis and Learning (OPTIMAL), State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics, Xi'an, China
Abstract: Band selection is an important preprocessing step for hyperspectral image processing. Many valid criteria have been proposed for band selection, and these criteria model band selection as a single-objective optimization problem. In this paper, a novel multiobjective model is first built for band selection. In this model, two objective functions with a conflicting relationship are designed. One objective function is set as information entropy to represent the information contained in the selected band subsets, and the other one is set as the number of selected bands. Then, based on this model, a new unsupervised band selection method called multiobjective optimization band selection (MOBS) is proposed. In the MOBS method, these two objective functions are optimized simultaneously by a multiobjective evolutionary algorithm to find the best tradeoff solutions. The proposed method shows two unique characters. It can obtain a series of band subsets with different numbers of bands in a single run to offer more options for decision makers. Moreover, these band subsets with different numbers of bands can communicate with each other and have a coevolutionary relationship, which means that they can be optimized in a cooperative way. Since it is unsupervised, the proposed algorithm is compared with some related and recent unsupervised methods for hyperspectral image band selection to evaluate the quality of the obtained band subsets. Experimental results show that the proposed method can generate a set of band subsets with different numbers of bands in a single run and that these band subsets have a stable good performance on classification for different data sets. © 2015 IEEE. (64 refs.)Main Heading: Multiobjective optimizationControlled terms: Classification (of information) - Decision making - Evolutionary algorithms - Image processing - Independent component analysis - Optimization - Set theory - SpectroscopyUncontrolled terms: Evolutionary multiobjective optimization - Hyper-spectral images - Hyperspectral image processing - Information entropy - Multi objective evolutionary algorithms - Multi-objective modeling - Objective functions - Single objective optimization problems
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Study of a symmetrically structured SPR sensor and its dual-wavelength differential method
Yang, Hai-Ma1, 2, 3; Ma, Cai-Wen1; Wang, Jian-Yu2; Liu, Jin4; Chen, Bao-Xue3 Source: Journal of Modern Optics, v 63, n 2, p 85-91, January 19, 2016
; ISSN: 09500340, E-ISSN: 13623044; DOI: 10.1080/09500340.2015.1066455;
Publisher: Taylor and Francis Ltd.Author affiliation: 1 Xian Institute of Optics and Precision Mechanics of CAS, Xian, China2 University of Chinese, Academy of Sciences, Beijing, China3 School of Optical-Electrical and Computer Engineering, University of Shanghai for Science and Technology, Shanghai, China4 College of Electronic and Electrical Engineering, Shanghai University of Engineering Science, Shanghai, China
Abstract: This study investigates a novel structure for surface plasmon resonance sensing and its dual-wavelength differential method. The surface plasmon wave is excited by a planar waveguide, which is prepared through the ion-exchange method. The distribution of refractive indices is fitted by the Fermi function. The sensing structure is based on a symmetric structure with a metal layer, a measured medium, and another metal layer. The condition for refractive index matching changes with the thicknesses of test samples, thus the test range can be adjusted using this structure. Given two appropriate wavelengths and for detection by the intensity method and an increase in the refractive index, the intensity variety at can be positive, whereas that at can be negative. When the refractive indices are determined based on differential values, sensitivity is improved. Solutions with refractive index values ranging from 1.33 to 1.428 are detected in the experiments using the single-wavelength method and the dual-wavelength differential method. Results show that the differential detection method enhances the adjustability and sensitivity of the SPR sensor in combination with a symmetric structure. © 2015 Taylor & Francis. (16 refs.)Main Heading: Refractive indexControlled terms: Ion exchange - Planar waveguides - Plasmons - Surface plasmon resonance - WaveguidesUncontrolled terms: Differential detection - Differential methods - Fermi functions - Ion-exchange methods - Refractive index matching - Surface plasmon resonance sensing - Surface plasmon waves - Symmetric structures
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Effect of energy density and feeding speed on micro-holes drilling in SiC/SiC composites by picosecond laser
Liu, Yongsheng1; Wang, Jing1; Li, Weinan2; Wang, Chunhui1; Zhang, Qing1; Yang, Xiaojun2; Cheng, Laifei1 Source: International Journal of Advanced Manufacturing Technology, v 84, n 9-12, p 1917-1925, June 1, 2016
; ISSN: 02683768, E-ISSN: 14333015; DOI: 10.1007/s00170-015-7844-1;
Publisher: Springer-Verlag London LtdAuthor affiliation: 1 Science and Technology on Thermostructure Composite Materials Laboratory, Northwestern Polytechnical University, Xi’an; Shaanxi; 710072, China2 State Key Laboratory of Transient Optics and Photonics, Xi’an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi’an; Shaanxi; 710068, China
Abstract: Picosecond laser machining is an important modern technology for materials with high hardness. In this paper, micro-holes with several hundred micrometer diameter were drilled in SiC/SiC composite using picosecond laser, and the quality of the micro-holes under different machining parameters was investigated in detail. The results indicated that energy density and feeding speed had remarkable effect on the micro-hole quality. The roundness of the micro-holes on the laser entry side was rarely affected by energy density and feeding speed. However, the roundness of the micro-holes on the laser exit side and micro-hole diameters along processing direction were quite sensitive to the energy density and feeding speed. Feeding speed had little influence on the quality of drilling holes, except for more debris on the entry side with 11.2 μm/s feeding speed. © 2015, Springer-Verlag London. (24 refs.)Main Heading: FeedingControlled terms: Silicon carbide - SpeedUncontrolled terms: Drilling holes - Energy density - Feeding speed - High hardness - Machining parameters - Modern technologies - Picosecond laser - SiC/SiC composites
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Demonstration of flexible optical time-division multiplexing system for high-speed free-space optical communications
Hu, Hui1, 2, 3; Qian, Fengchen1, 2; Xie, Xiaoping1; Duan, Tao1; Feng, Huan1, 2 Source: Journal of Optics (India), v 45, n 1, March 1, 2016
; ISSN: 09728821, E-ISSN: 09746900; DOI: 10.1007/s12596-016-0318-5;
Publisher: Optical Society of IndiaAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi’an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi’an, China2 Graduate University of Chinese Academy of Sciences, Beijing, China3 The School of Science, Xi’an Jiaotong University, Xi’an, China
Abstract: A high-speed free-space optical communication scheme based on optical time-division multiplexing (OTDM) is experimentally demonstrated. By multiplexing eight 2.5Gb/s base-rate signals, which is generated from a repetition-tunable actively mode-locked fiber ring laser modulated by pseudo-random binary sequence data stream, a 20Gb/s OTDM packet is obtained. After 50 m high-speed FSO system transmission, the 20Gb/s OTDM packet is injected into a highly nonlinear fiber (HNLF) loop to realize polarization-insensitive de-multiplexing based on four-wave mixing (FWM). Experimental results show that the OTDM de-multiplexer bit error rate (BER) can achieve 10−9level with steady operation over 24 h, proving the practicality of this system. © 2016, The Optical Society of India. (14 refs.)Main Heading: Optical communicationControlled terms: Binary sequences - Bit error rate - Demultiplexing - Error analysis - Four wave mixing - Locks (fasteners) - Mode-locked fiber lasers - Multiplexing - Multiplexing equipment - Nonlinear optics - Optical fiber communication - Ring lasers - Time division multiplexingUncontrolled terms: Fiber-ring lasers - Free Space Optical communication - Highly nonlinear fiber(HNLF) - Mode-locked - Optical time division multiplexing - Optical time division multiplexing systems - Polarization-insensitive - Pseudo-random binary sequences
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Decision-making method of strategy intelligence based on the lifecycle model for technology equipages
Ma, Nan1; Zhang, Li1; Zhao, Jian1; Xue, Yuan1; Guo, Huinan2 Source: Advances in Energy, Environment and Materials Science - Proceedings of the International Conference on Energy, Environment and Materials Science, EEMS 2015, p 839-843, 2016, Advances in Energy, Environment and Materials Science - Proceedings of the International Conference on Energy, Environment and Materials Science, EEMS 2015; ISBN-13: 9781138029316; Conference: International Conference on Energy, Environment and Materials Science, EEMS 2015, August 25, 2015 - August 26, 2015;
Publisher: CRC Press/BalkemaAuthor affiliation: 1 Air Force Engineering University, Science College, Xi’an, Shaanxi, China2 Xi’an Institute of Optics and Precision Mechanics Chinese Academy of Sciences, Xi’an, Shaanxi, China
Abstract: Technology literatures contain useful information regarding strategy intelligence, which can be utilized through modern computer-aided technique and digital data mining method. In order to provide an effective decision support for military equipage strategy, we propose a novel technology lifecycle model, which can clearly describe the trend of development of a core technology. Meanwhile, a decision-making method is proposed that provides a new approach to analyze literature intelligence. To approve the proposed method, an actual case about FSS is selected, and simulation analysis shows that the proposed method can accurately analyze transformation relationship between technology and new equipages, which is a useful decision support mode to policymakers. © 2016 Taylor & Francis Group, London. (10 refs.)Main Heading: Data miningControlled terms: Decision making - Decision support systems - Life cycleUncontrolled terms: Computer aided technique - Core technology - Decision supports - Decision-making method - Life cycle model - New approaches - Policy makers - Simulation analysisClassification Code: 723.2 Data Processing and Image ProcessingData Processing and Image Processing - 912.2 ManagementManagement
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Preparation and characterization of self-cleaning and anti-reflection ZnO-SiO2nanometric films
Guo, Zhao-Long1, 2; Zhao, Hai-Xin1; Zhao, Wei1 Source: Wuli Xuebao/Acta Physica Sinica, v 65, n 6, March 20, 2016; Language: Chinese
; ISSN: 10003290; DOI: 10.7498/aps.65.064206; Article number: 064206;
Publisher: Institute of Physics, Chinese Academy of SciencesAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, China2 University of the Chinese Academy of Sciences, Beijing 1, China
Abstract: Unlike the general anti-reflection and self-cleaning film such as SiO2and TiO2-SiO2, the ZnO-SiO2nanometric film used as a substrate of excellent transparency in visible region and effective photo-catalytic self-cleaning under UV illumination is seldom studied in the application as a substrate;however, it has a lot of advantages including high transmittance and low refractivity. In this paper, a self-cleaning and anti-reflection ZnO-SiO2nanometric film is successfully fabricated by using a sol-gel dip-coating method. The morphology, crystal structure, surface microstructure and light transmittance of the obtained products are characterized by techniques such as TEM, SAD, XRD, SEM, DTA and UV-vis. Photo-catalytic degradation of the methylene blue (MB) in aqueous solution is used as probe reaction to evaluate the photo-catalytic activity of ZnO-SiO2nanometric film. The TEM images reveal that the as-prepared ZnO nanoparticles are spherical grains with diameters of 12-20 nm, the average grain diameter is about 14.51 nm. ZnO nanoparticles obtained are of hexagonal wurtzite structure revealed by XRD pattern and there exist no other diffraction peaks. Furthermore, the SAD results show that ZnO microstructurs have good crystallinity. In addition, the ZnO grain size is about 14.41 nm by using the Scherrer formula calculation, which is consistent with the TEM results by the Gauss simulation. The UV-vis spectra reveal that the ultraviolet characteristic absorption peak of ZnO-SiO2composite films is located at 368 nm and 375 nm after annealing at different temperatures such as 300 and 450, corresponding to the band gaps of 3.37 eV and 3.31 eV, respectively. It is highly consistent with that obtained from pure ZnO nanoparticles. Increasing the annealing temperature results in a lower refractive index and the increases of the porosity in of the ZnO-SiO2composite films. It has a uniformly refractive index value about 1.23-1.25 and a high porosity value about 50.3%-54.7% when the annealing temperature is 450. Experimental results show that the ZnO-SiO2composite film can enhance the light transmittance of the quartz substrate, due to its lower reflective index and higher porosity. Compared with the quartz substrate, the average optical transmission rate of the quartz glass coated with ZnO-SiO2composite films is increased by about 4.17% at 400-800 nm, which favors greatly anti-reflection characteristics in a wide spectrum range. Meanwhile, the ZnO-SiO2composite films are found to be efficient for photo-catalytically degradation of methylene blue dye under UV illumination, which favors greatly the self-cleaning function. © 2016, Chinese Physical Society. (29 refs.)Main Heading: Composite filmsControlled terms: Annealing - Aromatic compounds - Catalyst activity - Cleaning - Crystal microstructure - Crystal structure - Crystal symmetry - Energy gap - Film preparation - Light transmission - Metal nanoparticles - Nanoparticles - Porosity - Quartz - Refractive index - Sol-gel process - Sol-gels - Solutions - Zinc oxide - Zinc sulfideUncontrolled terms: Characteristic absorption - Hexagonal wurtzite structure - Nano-ZnO - Photo catalytic degradation - Photo-catalytic - Photocatalytic activities - Sol-gel dip-coating method - Surface microstructuresClassification Code: 482.2 MineralsMinerals - 537.1 Heat Treatment ProcessesHeat Treatment Processes - 741.1 Light/OpticsLight/Optics - 761 NanotechnologyNanotechnology - 802.3 Chemical OperationsChemical Operations - 804 Chemical Products GenerallyChemical Products Generally - 812.3 GlassGlass - 931.2 Physical Properties of Gases, Liquids and SolidsPhysical Properties of Gases, Liquids and Solids - 933.1.1 Crystal LatticeCrystal Lattice
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


A parallel primal-dual splitting method for image restoration
He, Chuan1; Hu, Changhua1; Li, Xuelong2; Zhang, Wei1 Source: Information Sciences, v 358-359, p 73-91, September 1, 2016
; ISSN: 00200255; DOI: 10.1016/j.ins.2016.04.004;
Publisher: Elsevier Inc.Author affiliation: 1 High-Tech Institute of Xi'an, Xi'an; Shaanxi; 710025, China2 Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; Shaanxi; 710199, China
Abstract: We develop a parallel primal-dual splitting method to solve large-scale image restoration problems, which involve the sum of several linear-operator-coupled nonsmooth but proximable terms. With the proposed method, the objective function is decomposed into pieces that can be processed individually. No inverse operator is involved in our method and the highly parallel structure makes it preferable in distributed computation. The convergence is proven and the convergence rate is analyzed. Besides, its equivalence to the relaxed parallel linearized alternating direction method of multipliers (PLADMM) is addressed. Applications to image restoration problems with compound l1-regularizer and comparisons with state-of-the-art methods are detailed to show the superiority of the proposed method. © 2016 Elsevier Inc. All rights reserved. (38 refs.)Main Heading: Inverse problemsControlled terms: Image reconstruction - Linearization - Mathematical operators - RestorationUncontrolled terms: Alternating direction method of multipliers - Compound l1-regularization - Convergence rates - Distributed computations - Image restoration problem - Objective functions - Primal-dual - State-of-the-art methods
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Optical microfiber knot resonator (MKR) and its slow-light performance
Ren, Liyong1; Xu, Yiping1, 2; Ma, Chengju1, 2; Wang, Yingli1; Kong, Xudong1, 2; Liang, Jian1; Ju, Haijuan1; Ren, Kaili1, 2; Lin, Xiao1, 2 Source: Journal of Physics: Conference Series, v 680, n 1, February 3, 2016, 5th International Conference on Advances in Optoelectronics and Micro/Nano-Optics, AOM 2015
; ISSN: 17426588, E-ISSN: 17426596; DOI: 10.1088/1742-6596/680/1/012032; Article number: 012032; Conference: 5th International Conference on Advances in Optoelectronics and Micro/Nano-Optics, AOM 2015, October 28, 2015 - October 31, 2015;
Publisher: Institute of Physics PublishingAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, China2 University of Chinese Academy of Sciences, Beijing, China (36 refs.)
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Optimization of the electron collection efficiency of a large area MCP-PMT for the JUNO experiment
Chen, Lin1, 2, 5; Tian, Jinshou2; Liu, Chunliang5; Wang, Yifang3; Zhao, Tianchi3; Liu, Hulin2; Wei, Yonglin2; Sai, Xiaofeng2; Chen, Ping1, 2; Wang, Xing2; Lu, Yu2; Hui, Dandan1, 2; Guo, Lehui1, 2; Liu, Shulin3; Qian, Sen3; Xia, Jingkai3; Yan, Baojun3; Zhu, Na3; Sun, Jianning4; Si, Shuguang4; Li, Dong4; Wang, Xingchao4; Huang, Guorui4; Qi, Ming6 Source: Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, v 827, p 124-130, August 11, 2016
; ISSN: 01689002; DOI: 10.1016/j.nima.2016.04.100;
Publisher: ElsevierAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics (XIOPM), Chinese Academy of Sciences (CAS), Xi'an; 710119, China2 Graduate School, Chinese Academy of Sciences (CAS), Beijing; 100049, China3 Institute of High Energy Physics (IHEP), CAS, Beijing; 100049, China4 North Night Vision Technology (NNVT) CO., LTD, Nanjing; 210110, China5 Xi'an Jiaotong University, Xi'an; 710049, China6 Nanjing University, Nanjing; 210093, China
Abstract: A novel large-area (20-inch) photomultiplier tube based on microchannel plate (MCP-PMTs) is proposed for the Jiangmen Underground Neutrino Observatory (JUNO) experiment. Its photoelectron collection efficiency Ceis limited by the MCP open area fraction (Aopen). This efficiency is studied as a function of the angular (θ), energy (E) distributions of electrons in the input charge cloud and the potential difference (U) between the PMT photocathode and the MCP input surface, considering secondary electron emission from the MCP input electrode. In CST Studio Suite, Finite Integral Technique and Monte Carlo method are combined to investigate the dependence of Ceon θ, E and U. Results predict that Cecan exceed Aopen, and are applied to optimize the structure and operational parameters of the 20-inch MCP-PMT prototype. Ceof the optimized MCP-PMT is expected to reach 81.2%. Finally, the reduction of the penetration depth of the MCP input electrode layer and the deposition of a high secondary electron yield material on the MCP are proposed to further optimize Ce. © 2016 Elsevier B.V. All rights reserved. (25 refs.)Main Heading: Image storage tubesControlled terms: Electrodes - Electron emission - Electrons - Microchannels - Monte Carlo methods - Photomultipliers - Plates (structural components) - Secondary emissionUncontrolled terms: Collection efficiency - Finite integral techniques - Micro channel plate - Operational parameters - Photo multiplier tube - Photoelectron collection efficiency - Secondary electron emissions - Secondary electron yieldClassification Code: 408.2 Structural Members and ShapesStructural Members and Shapes - 714.1 Electron TubesElectron Tubes - 922.2 Mathematical StatisticsMathematical Statistics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Theoretical and experimental analysis of excessively tilted fiber gratings
Yan, Zhijun1, 2; Wang, Hushan1; Wang, Changle2; Sun, Zhongyuan2; Yin, Guolu2; Zhou, Kaiming1, 2; Wang, Yishan1; Zhao, Wei1; Zhang, Lin2 Source: Optics Express, v 24, n 11, p 12107-12115, May 30, 2016; E-ISSN: 10944087; DOI: 10.1364/OE.24.012107;
Publisher: OSA - The Optical SocietyAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China2 Institute of Photonic and Technologies, Aston University, Birmingham; B4 7ET, United Kingdom
Abstract: We have theoretically and experimentally investigated the dual-peak feature of tilted fiber gratings with excessively tilted structure (named as Ex-TFGs). We have explained the dual-peak feature by solving eigenvalue equations for TM0mand TE0mof a circular waveguide, in which the TE (transverse electric) and TM (transverse magnetic) core modes are coupled into TE and TM cladding modes, respectively. Meanwhile, in the experiment, we have verified that one of the dual peaks at the shorter wavelength is due to the TM mode coupling whereas the other one at the longer wavelength arises from TE mode coupling when a linearly polarized light launched into the Ex-TFG. We have also investigated the peak separation of TE and TM cladding mode for different surrounding medium refractive indexes (SRI), revealed that the dual peaks separation is decreasing as increasing of SRI, which agrees very well with the theoretical analysis results. ©2016 Optical Society of America. (31 refs.)Main Heading: Refractive indexControlled terms: Circular waveguides - Eigenvalues and eigenfunctionsUncontrolled terms: Eigenvalue equations - Experimental analysis - Linearly polarized light - Peak separations - Shorter wavelength - Tilted fiber gratings - Transverse electrics - Transverse magneticClassification Code: 714.3 WaveguidesWaveguides - 741.1 Light/OpticsLight/Optics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Unsupervised Band Selection Based on Evolutionary Multiobjective Optimization for Hyperspectral Images
Gong, Maoguo1; Zhang, Mingyang1; Yuan, Yuan2 Source: IEEE Transactions on Geoscience and Remote Sensing, v 54, n 1, p 544-557, January 1, 2016
; ISSN: 01962892; DOI: 10.1109/TGRS.2015.2461653; Article number: 7214263;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 Ministry of Education, International Research, Center for Intelligent Perception and Computation, Xidian University, Xi'an, China2 Center for OPTical IMagery Analysis and Learning (OPTIMAL), State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics, Xi'an, China
Abstract: Band selection is an important preprocessing step for hyperspectral image processing. Many valid criteria have been proposed for band selection, and these criteria model band selection as a single-objective optimization problem. In this paper, a novel multiobjective model is first built for band selection. In this model, two objective functions with a conflicting relationship are designed. One objective function is set as information entropy to represent the information contained in the selected band subsets, and the other one is set as the number of selected bands. Then, based on this model, a new unsupervised band selection method called multiobjective optimization band selection (MOBS) is proposed. In the MOBS method, these two objective functions are optimized simultaneously by a multiobjective evolutionary algorithm to find the best tradeoff solutions. The proposed method shows two unique characters. It can obtain a series of band subsets with different numbers of bands in a single run to offer more options for decision makers. Moreover, these band subsets with different numbers of bands can communicate with each other and have a coevolutionary relationship, which means that they can be optimized in a cooperative way. Since it is unsupervised, the proposed algorithm is compared with some related and recent unsupervised methods for hyperspectral image band selection to evaluate the quality of the obtained band subsets. Experimental results show that the proposed method can generate a set of band subsets with different numbers of bands in a single run and that these band subsets have a stable good performance on classification for different data sets. © 2015 IEEE. (64 refs.)Controlled terms: algorithm - decision making - entropy - experimental study - image processing - model test - multiobjective programming - optimization - spectral analysis - unsupervised classificationClassification Code: 71.8.5.4 Remote sensing: numerical and image analysisRemote sensing: numerical and image analysis
Database: GEOBASE
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Linearly, radially and azimuthally polarized femtosecond laser induced periodic surface structures on amorphous alloy
Li, Chen1, 2; Cheng, Guang-Hua1 Source: Guangzi Xuebao/Acta Photonica Sinica, v 45, n 8, August 1, 2016
; ISSN: 10044213; DOI: 10.3788/gzxb20164508.0832001; Article number: 0832001;
Publisher: Chinese Optical SocietyAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics of CAS, Xi'an; 710119, China2 University of Chinese Academy of Science, Beijing; 10049, China
Abstract: The formation mechanism of Laser Induced Periodic Surface Structures (LIPSS) on the amorphous alloy Zr44Ti11Cu10Ni10Be25(at%) was investigated. In experiment, LIPSS on the amorphous alloy were produced by ultrashort laser pulses of 120 fs duration at 800 nm wavelength in three types of laser polarizations (linear, radial and azimuthal polarization). These LIPSS are comprised of Low-Spatial-Frequency LIPSS (LSFL) with the periodicity of 652~723 nm and macro-ripples with the periodicity of 1 304~1 765 nm. By Finite-Difference Time-Domain (FDTD) simulations, formation mechanism of macro-ripples can be explained by the interference between laser and modulated scattered electromagnetic wave induced by rough surface. In the condition of three types of laser polarizations (linear, radial and azimuthal polarization), FDTD simulation results agree with experimental results, proving the effectiveness of the macro-ripple formation mechanism. © 2016, Science Press. All right reserved. (23 refs.)Main Heading: Periodic structuresControlled terms: Amorphous alloys - Electromagnetic waves - Finite difference time domain method - Light modulators - Polarization - Surface structure - Ultrafast lasers - Ultrashort pulsesUncontrolled terms: Amorphous metals - Finite -difference time domains (FDTD) - Laser-induced periodic surface structures - Spatial light modulators - Ultrafast laser processingClassification Code: 531 Metallurgy and MetallographyMetallurgy and Metallography - 711 Electromagnetic WavesElectromagnetic Waves - 744.1 Lasers, GeneralLasers, General - 921 MathematicsMathematics - 931.2 Physical Properties of Gases, Liquids and SolidsPhysical Properties of Gases, Liquids and Solids - 931.3 Atomic and Molecular PhysicsAtomic and Molecular Physics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Optical design for large depth of field
Shen, Yang1, 2; Wang, Hu1; Yue, Pan1, 2; Xue, Yaoke1; Liu, Jie1; Ye, Shuifu1 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 9796, 2016, Selected Papers of the Photoelectronic Technology Committee Conferences held November 2015
; ISSN: 0277786X, E-ISSN: 1996756X; ISBN-13: 9781628418811; DOI: 10.1117/12.2229621; Article number: 97962Q; Conference: International Symposia on Atmosphere Optics and Adaptive Optics, Testing and Driving of Laser Fusion Energy Technology, High-performance Special Optical Film Technology, Novel Navigation Technology, Monitoring, Early Warning, Removal Technology of Space Targets and Debris, and UAV Payload Technology, November 15, 2015 - November 28, 2015; Sponsor: Chinese Academy of Engineering; Chinese Society for Optical Engineering; National Natural Science Foundation of China;
Publisher: SPIEAuthor affiliation: 1 Xi'an Institute of Optics and Precision Mechanics, CAS, Xi'an; 710119, China2 University of Chinese Academy of Sciences, Beijing; 100049, China
Abstract: Optical system with large depth of field and large field of view has been designed. To enforce optical system with focal length of 6 mm to imaging the object with object length of 200mmm-1200mm, accord to the equation of depth of field, in case of the CCD sensor with pixel of 5.5umx 5.5um square area, the entrance pupil diameter to ideal imaging will be 0.423mm. To enlarge the modulation transfer function (MTF) at spatial frequency of 90 lp/mm, the entrance pupil diameter is enlarged to 1mm. After design and optimization, with field of view of 80°, within object length of 200mm - 1200mm, the optical system can imaging well, the modulation transfer function (MTF) at spatial frequency of 90lp/mm is larger than 0.1, the distortion of full field of viewed is less than 3%.The optical system can be widely used in machine vision, surveillance cameras, etc. © 2016 SPIE. (10 refs.)Main Heading: Adaptive opticsControlled terms: Computer vision - Focusing - Modulation - Optical design - Optical systems - Optical transfer function - Security systems - Space debris - Transfer functionsUncontrolled terms: Depth of field - Design and optimization - Entrance pupil - Field of views - Focal lengths - Large field of views - Spatial frequency - Surveillance camerasClassification Code: 656.1 Space FlightSpace Flight - 741 Light, Optics and Optical DevicesLight, Optics and Optical Devices - 914.1 Accidents and Accident PreventionAccidents and Accident Prevention - 921 MathematicsMathematics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Calibration of stray light based on point source transmittance measurement system
Xu, Liang1, 2; Gao, Li-Min1; Zhao, Jian-Ke1; Liu, Feng1; Zhou, Yan1; Li, Zhao-Hui1, 2; Yang, Fei3; Zhao, Qing1, 2 Source: Guangxue Jingmi Gongcheng/Optics and Precision Engineering, v 24, n 7, p 1607-1614, July 1, 2016; Language: Chinese
; ISSN: 1004924X; DOI: 10.3788/OPE.20162407.1607;
Publisher: Chinese Academy of SciencesAuthor affiliation: 1 Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China2 University of Chinese Academy of Sciences, Beijing; 100049, China3 AVIC Xi'an Aircraft Industry (Group) Company LTD., Xi'an; 710089, China
Abstract: To improve the stray light testing ability and calibration accuracy of the stray light equipment used in test of the Point Source Transmittance (PST), a calibration lens was proposed to calibrate the testing range and testing accuracy of the equipment in a large off-axial angle. By using a simple physical model, the calibration lens was designed in a laboratory. The physical parameters of the calibration lens were measured, then these parameters were taken into the TracePro to calculate the PSTs in different off-axial angles. Finally, the calculated result and the tested result of PSTs were compared, and the test accuracy of the equipment were obtained. The experimental results indicate that the difference between calculate results and testing results of the calibration lens is better than lg/0.5, meeting the need of testing accuracy calibration of the stray light equipment in testing PSTs and providing a reliable reference for the absolute measurement of PSTs. This technology solves the problem in testing accuracy calibration of PST measuring systems. © 2016, Science Press. All right reserved. (12 refs.)Main Heading: CalibrationControlled terms: Ability testing - Distribution functions - Equipment - Stray lightUncontrolled terms: Absolute measurements - Bidirectional reflectance distribution functions - Calibration accuracy - Measuring systems - Physical parameters - Simple Physical Models - Stray light testing - Transmittance measurementsClassification Code: 741.1 Light/OpticsLight/Optics - 901 Engineering ProfessionEngineering Profession - 912.4 PersonnelPersonnel - 922.1 Probability TheoryProbability Theory
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Robust object tracking via diverse templates
Wu, Siyuan1, 2; Li, Xuelong1; Lu, Xiaoqiang1 Source: IEEE CITS 2016 - 2016 International Conference on Computer, Information and Telecommunication Systems, August 16, 2016, IEEE CITS 2016 - 2016 International Conference on Computer, Information and Telecommunication Systems; ISBN-13: 9781509034406; DOI: 10.1109/CITS.2016.7546394; Article number: 7546394; Conference: 2016 International Conference on Computer, Information and Telecommunication Systems, CITS 2016, July 6, 2016 - July 8, 2016; Sponsor: State Key Laboratory of Integrated Services Networks (ISN); Xidian University; Yunnan Minzu University;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 Center for OPTical IMagery Analysis and Learning (OPTIMAL), Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, Shaanxi; 710119, China2 University of the Chinese, Academy of Sciences, 19A Yuquanlu, Beijing; 100049, China
Abstract: Robust object tracking is a challenging task in computer vision. Since the appearance of the target changes frequently, how to build and update the appearance model is crucial. In this paper, to better represent the object dynamically, we propose a robust object tracker based on diverse templates. First, we construct diverse multiple templates using the determinantal point process algorithm adaptively, which efficiently detects the most diverse subset of a set. Second, a patch-matching method is employed to propagate every template density to the next frame, and a voting map for each template is constructed by all matching patches. Third, a weighted Bayesian filter framework aggregates all voting maps to optimize target state. Finally, in order to maintain the diversity of multiple templates, we dynamically add, remove and replace the target from templates. Experimental results prove that the proposed method outperforms state-of-the-art tracking algorithms significantly in terms of center position errors and success rates. © 2016 IEEE. (23 refs.)Main Heading: Image matchingControlled terms: Computer vision - Image processing - Tracking (position)Uncontrolled terms: Appearance modeling - Bayesian filters - Matching patch - Multiple templates - Object Tracking - Position errors - State of the art - Tracking algorithmClassification Code: 723.5 Computer ApplicationsComputer Applications
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Nonspherical hollow α-Fe2O3structures synthesized by stepwise effect of fluoride and phosphate anions
Wang, Conghui1, 5; Shi, Jing4; Cui, Xinmin1, 5; Wang, Huixiang1, 5; Wu, Jianghong1, 5; Zhang, Chenghua1, 3; Wang, Liancheng1; Lv, Baoliang1; Xu, Yao2 Source: Journal of Materials Chemistry A, v 4, n 28, p 11000-11008, 2016
; ISSN: 20507488, E-ISSN: 20507496; DOI: 10.1039/c6ta03228a;
Publisher: Royal Society of ChemistryAuthor affiliation: 1 State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan; 030001, China2 State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an Shaanxi; 710119, China3 Synfuels China Technology Co. Ltd., Beijing; 101407, China4 Analytical Instrumentation Center, Institute of Coal Chemistry, Chinese Academy of Sciences, 27 South Taoyuan Road, Taiyuan; 030001, China5 University of Chinese Academy of Sciences, Beijing; 100049, China
Abstract: Despite the significant progress in making hollow structures, it is still a challenge to synthesize some specialized hollow structures. In the present work, we obtained a new hollow hematite structure, tube-in-dodecahedron, by using the stepwise influences of fluoride and phosphate anions. Based on condition-dependent experiments, we proposed a "nucleation-aggregation-recrystallition and etching" mechanism, which also directed us to synthesize a series of hematite hollow structures, including hollow dodecahedron and hollow ellipsoid. The concentration of phosphate was found to play a decisive role in the control of these hollow structures. 0.08 mM is the critical point for keeping the top facets of dodecahedral hematite particles while 0.2 mM is the upper limit for keeping the lateral facets. The magnetic properties of these synthesized hollow hematite structures were found to be closely associated with the structures. The synthesized tube-in-dodecahedral hematite particles exhibited excellent photocatalytic reactivity toward organic dyes. © 2016 The Royal Society of Chemistry. (48 refs.)Main Heading: HematiteControlled terms: Fluorine compoundsUncontrolled terms: Hematite particles - Hematite structure - Hollow structure - Non-Spherical - Organic dye - Phosphate anions - Photocatalytic reactivity - Upper limitsClassification Code: 482.2 MineralsMinerals
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Effects of fluorine on the properties of Yb/Ce co-doped aluminosilicate preforms prepared by MCVD with organic chelate precursor doping technique
Li, Weinan1; Luo, Rong1; Li, Chao1; Gao, Song1; Chang, Chang1; Hou, Chaoqi1; Zhao, Baoyin1 Source: Journal of Non-Crystalline Solids, v 449, p 119-124, October 1, 2016
; ISSN: 00223093; DOI: 10.1016/j.jnoncrysol.2016.07.016;
Publisher: ElsevierAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics of Chinese Academy of Sciences (CAS), Xi'an; 710119, China
Abstract: Co-doped Yb/Ce aluminosilicate fiber preforms with less than 1 Wt% fluorine were prepared by MCVD with organic chelate precursor doping technique at 1400 °C. Fluorine content characterized by electron probe microanalysis decreased with increasing SiF4flow and flow ratio of SiF4/SiCl4. Under maximum SiF4flow the concentrations of Yb2O3and CeO2in the perform core were only as much as 17% and 25% under minimum SiF4flow, respectively, but smaller refractive index change was only shown in fiber core. The reason was that the reaction of SiF4with Al2O3,Yb2O3,CeO2were intensified with increasing flow ratio of SiF4/SiCl4and then resulted in producing more exhaust gas such as AlF3, YbF3and CeF4. Raman spectra of core glasses with < 0.5 Wt% fluorine present different Raman shifts from F doped silica glass with 1–3.3 Wt% fluorine: 945 cm− 1of [Formula presented] stretching bond was not observed, and with growth of fluorine content antisymmetric stretching vibrations of Si-O-Si linkages split from an envelope of 1188 cm− 1into two peaks or three peaks shifted higher frequency. At the same time, Boson peak near 125 cm− 1shifted to lower frequency. They were attributed to some minor changes of glass's network structure due to introducing lower fluorine into core glasses. On base of bonding energy measured by X-ray photoelectric spectroscopy, the plane graph describing the complex bonding distribution with F in core was supplied to in order to illustrate network structure change. © 2016 Elsevier B.V. (32 refs.)Main Heading: FluorineControlled terms: Aluminosilicates - Chelation - Complex networks - Doping (additives) - Electron probe microanalysis - Glass - Photoelectricity - Preforming - Raman scattering - Refractive index - Silica - Stretching - YtterbiumUncontrolled terms: Aluminosilicate fibers - Antisymmetric stretching - Chelate precursor - Co-doped - Network structure change - Network structures - Refractive index changes - X-ray photoelectric spectroscopyClassification Code: 535.2 Metal FormingMetal Forming - 547.2 Rare Earth MetalsRare Earth Metals - 722 Computer Systems and EquipmentComputer Systems and Equipment - 741.1 Light/OpticsLight/Optics - 801 ChemistryChemistry - 802.2 Chemical ReactionsChemical Reactions - 804 Chemical Products GenerallyChemical Products Generally - 812.3 GlassGlass
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Navigation and geo-tracking system of UAV EO payload
Chen, Ying1; Zhen, Kang1; Xue, Yuanyuan1; Zhang, Xiajiang1; Li, Yingjuan1; Tang, Chao2 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 9796, 2016, Selected Papers of the Photoelectronic Technology Committee Conferences held November 2015
; ISSN: 0277786X, E-ISSN: 1996756X; ISBN-13: 9781628418811; DOI: 10.1117/12.2229478; Article number: 97962N; Conference: International Symposia on Atmosphere Optics and Adaptive Optics, Testing and Driving of Laser Fusion Energy Technology, High-performance Special Optical Film Technology, Novel Navigation Technology, Monitoring, Early Warning, Removal Technology of Space Targets and Debris, and UAV Payload Technology, November 15, 2015 - November 28, 2015; Sponsor: Chinese Academy of Engineering; Chinese Society for Optical Engineering; National Natural Science Foundation of China;
Publisher: SPIEAuthor affiliation: 1 Xi'an Institute of Applied Optical, Xi'an; 710065, China2 Xi'an Institute of AVIC Computing Technique, Xi'an; 710068, China
Abstract: A multi-function system based on inertial measurement unit (IMU) is introduced, which can fulfill navigation, attitude measurement of LOS in payload, platform stabilization and tracking control. The IMU is integrated with electro-optical sensors and a laser range finder on gimbals, which performs attitude calculation and navigation by constructing navigation coordinates in a mathematic platform, and the platform navigation information is obtained by transformation matrix between platform and gimbal coordinates. The platform comprising of gyros, electro-optical sensors and servo mechanism is capable of stabilizing line of sight and could be used to geo-tracking in the relevant field of view (FOV).The system can determine geography coordinates of the host platform and target only with navigation information and laser ranging data. The geo-tracking system always locked the target image at the center of FOV by calculating spatial geometry and adjusting LOS attitude. This tracking is different from TV tracking and geographical reference image tracking, which may be influenced by fog and obscurant. When the UAV is flying over urban or mountain areas for rescue missions, it can avoid the loss of targets due to strong maneuver or LOS obscuration, and reduce the operation load and improve rescue efficiency. © 2016 SPIE. (9 refs.)Main Heading: Adaptive opticsControlled terms: Electrooptical devices - Linear transformations - Navigation - Optical sensors - Range finders - Space debris - Target tracking - Tracking (position) - Units of measurement - Unmanned aerial vehicles (UAV)Uncontrolled terms: Attitude measurement - Electrooptical sensors - Inertial measurement unit - Laser range finders - Line of Sight - Navigation in formation - Navigtion - Transformation matricesClassification Code: 652.1 Aircraft, GeneralAircraft, General - 656.1 Space FlightSpace Flight - 741.1 Light/OpticsLight/Optics - 741.3 Optical Devices and SystemsOptical Devices and Systems - 902.2 Codes and StandardsCodes and Standards - 921.3 Mathematical TransformationsMathematical Transformations - 943.1 Mechanical InstrumentsMechanical Instruments
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


High-precision algorithm of surface parameter of parabolic primary mirror for space solar telescope
Xu, Guangzhou1, 3; Ruan, Ping1; Yang, Jianfeng1; Li, Fu1; Yan, Xingtao1; Wang, Sen2 Source: Optik, v 127, n 22, p 10687-10696, November 1, 2016
; ISSN: 00304026; DOI: 10.1016/j.ijleo.2016.08.066;
Publisher: Elsevier GmbHAuthor affiliation: 1 Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China2 National Astronomical Observatories, Chinese Academy of Sciences, Beijing; 100012, China3 University of Chinese Academy of Sciences, Beijing; 100049, China
Abstract: The parabolic primary mirror (PM) of space solar telescope is sensitive to the serious external loads and surface variation of PM has large influence on the optical performance of the telescope. To evaluate the PM change under the external loads accurately, the high-precision algorithm based on the comprehensive surface parameter is presented. The discrete error of finite element discretization of optical surface is concerned for the first time and the elimination of discrete error is discussed as well. The calculation method of surface parameter including rigid body displacement, surface focus and root mean square is researched. Based on the high-precision algorithm, the surface parameter of PM under the isothermal temperature change is calculated and the law curve of surface parameter is also obtained with the change of temperature. The significant simulation result of surface parameter can effectively evaluate the surface change and guide the structure and environmental adaptation design of the PM. © 2016 Elsevier GmbH (14 refs.)Main Heading: Parameter estimationControlled terms: Algorithms - Errors - Mirrors - Rigid structures - TelescopesUncontrolled terms: Change of temperatures - Environmental adaptation - Finite-element discretization - Isothermal temperature - Optical performance - Rigid body displacement - Space solar telescope - Surface parameterClassification Code: 408 Structural DesignStructural Design - 741.3 Optical Devices and SystemsOptical Devices and Systems
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Extracting signal via stochastic resonance in the semiconductor optical amplifier
Zhao, Wulong1; Liu, Hongjun1; Sun, Qibing1; Huang, Nan1; Wang, Zhaolu1; Han, Jing1; Sun, Heng1 Source: Chinese Optics Letters, v 14, n 8, August 10, 2016; Language: Chinese
; ISSN: 16717694; DOI: 10.3788/COL201614.081901; Article number: 081901;
Publisher: Science PressAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinademy of Sciences, Xi'an; 710119, China
Abstract: The stochastic resonance based on optical bistability in the semiconductor optical amplifier is numerically investigated to extract a weak pulse signal buried in noise. The output property of optical bistability under different system parameters is analyzed, which determines the performance of the stochastic resonance. Through optimizing these parameters, the noise-hidden signal is extracted via stochastic resonance, in which the maximum cross-correlation gain higher than nine is obtained. This provides a novel technology for detecting a weak optical signal in various signal processing fields. © 2016 Chinese Optics Letters. (25 refs.)Main Heading: Signal processingControlled terms: Circuit resonance - Light amplifiers - Magnetic resonance - Optical properties - Optical switches - Resonance - Semiconductor optical amplifiers - Stochastic systemsUncontrolled terms: Maximum cross correlations - Optical signals - Output property - Pulse signal - Signal processing fields - Stochastic resonancesClassification Code: 701.2 Magnetism: Basic Concepts and PhenomenaMagnetism: Basic Concepts and Phenomena - 703.1 Electric NetworksElectric Networks - 714.2 Semiconductor Devices and Integrated CircuitsSemiconductor Devices and Integrated Circuits - 716.1 Information Theory and Signal ProcessingInformation Theory and Signal Processing - 741.1 Light/OpticsLight/Optics - 741.3 Optical Devices and SystemsOptical Devices and Systems - 931.1 MechanicsMechanics - 961 Systems ScienceSystems Science
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Pedestrian Detection Inspired by Appearance Constancy and Shape Symmetry
Cao, Jiale1; Pang, Yanwei1; Li, Xuelong2 Source: IEEE Transactions on Image Processing, v 25, n 12, p 5538-5551, December 2016
; ISSN: 10577149; DOI: 10.1109/TIP.2016.2609807; Article number: 7569095;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 School of Electronic Information Engineering, Tianjin University, Tianjin; 300072, China2 State Key Laboratory of Transient Optics and Photonics, Center for OPTical IMagery Analysis and Learning, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China
Abstract: Most state-of-the-art methods in pedestrian detection are unable to achieve a good trade-off between accuracy and efficiency. For example, ACF has a fast speed but a relatively low detection rate, while checkerboards have a high detection rate but a slow speed. Inspired by some simple inherent attributes of pedestrians (i.e., appearance constancy and shape symmetry), we propose two new types of non-neighboring features: side-inner difference features (SIDF) and symmetrical similarity features (SSFs). SIDF can characterize the difference between the background and pedestrian and the difference between the pedestrian contour and its inner part. SSF can capture the symmetrical similarity of pedestrian shape. However, it is difficult for neighboring features to have such above characterization abilities. Finally, we propose to combine both non-neighboring features and neighboring features for pedestrian detection. It is found that non-neighboring features can further decrease the log-average miss rate by 4.44%. The relationship between our proposed method and some state-of-the-art methods is also given. Experimental results on INRIA, Caltech, and KITTI data sets demonstrate the effectiveness and efficiency of the proposed method. Compared with the state-of-the-art methods without using CNN, our method achieves the best detection performance on Caltech, outperforming the second best method (i.e., checkerboards) by 2.27%. Using the new annotations of Caltech, it can achieve 11.87% miss rate, which outperforms other methods. © 2016 IEEE. (56 refs.)Main Heading: Feature extractionControlled terms: Adaptive boosting - Economic and social effects - Efficiency - Object detectionUncontrolled terms: Detection performance - Detection rates - Effectiveness and efficiencies - High detection rate - neighboring features - non-neighboring features - Pedestrian detection - State-of-the-art methodsClassification Code: 723 Computer Software, Data Handling and ApplicationsComputer Software, Data Handling and Applications - 723.2 Data Processing and Image ProcessingData Processing and Image Processing - 913.1 Production EngineeringProduction Engineering - 971 Social SciencesSocial Sciences
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Pedestrian Detection Inspired by Appearance Constancy and Shape Symmetry
Cao, Jiale1; Pang, Yanwei1; Li, Xuelong2 Source: IEEE Transactions on Image Processing, v 25, n 12, p 5538-5551, October 2016
; ISSN: 10577149; DOI: 10.1109/TIP.2016.2609807; Article number: 7569095;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 School of Electronic Information Engineering, Tianjin University, Tianjin; 300072, China2 State Key Laboratory of Transient Optics and Photonics, Center for OPTical IMagery Analysis and Learning, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China
Abstract: Most state-of-the-art methods in pedestrian detection are unable to achieve a good trade-off between accuracy and efficiency. For example, ACF has a fast speed but a relatively low detection rate, while checkerboards have a high detection rate but a slow speed. Inspired by some simple inherent attributes of pedestrians (i.e., appearance constancy and shape symmetry), we propose two new types of non-neighboring features: side-inner difference features (SIDF) and symmetrical similarity features (SSFs). SIDF can characterize the difference between the background and pedestrian and the difference between the pedestrian contour and its inner part. SSF can capture the symmetrical similarity of pedestrian shape. However, it is difficult for neighboring features to have such above characterization abilities. Finally, we propose to combine both non-neighboring features and neighboring features for pedestrian detection. It is found that non-neighboring features can further decrease the log-average miss rate by 4.44%. The relationship between our proposed method and some state-of-the-art methods is also given. Experimental results on INRIA, Caltech, and KITTI data sets demonstrate the effectiveness and efficiency of the proposed method. Compared with the state-of-the-art methods without using CNN, our method achieves the best detection performance on Caltech, outperforming the second best method (i.e., checkerboards) by 2.27%. Using the new annotations of Caltech, it can achieve 11.87% miss rate, which outperforms other methods. © 2016 IEEE. (56 refs.)Main Heading: Feature extractionControlled terms: Adaptive boosting - Economic and social effects - Efficiency - Object detectionUncontrolled terms: Detection performance - Detection rates - Effectiveness and efficiencies - High detection rate - neighboring features - non-neighboring features - Pedestrian detection - State-of-the-art methodsClassification Code: 723 Computer Software, Data Handling and ApplicationsComputer Software, Data Handling and Applications - 723.2 Data Processing and Image ProcessingData Processing and Image Processing - 913.1 Production EngineeringProduction Engineering - 971 Social SciencesSocial Sciences
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Analysis of a Si-nanocrystal strip-loaded waveguide for nonlinear applications
Wei, Pengjiang1; Wang, S.H.2; Little, Brent E.3; Chu, Sai Tak1 Source: 2016 21st OptoElectronics and Communications Conference, OECC 2016 - Held Jointly with 2016 International Conference on Photonics in Switching, PS 2016, October 26, 2016, 2016 21st OptoElectronics and Communications Conference, OECC 2016 - Held Jointly with 2016 International Conference on Photonics in Switching, PS 2016; ISBN-13: 9784885523052; Article number: 7718425; Conference: 21st OptoElectronics and Communications Conference, OECC 2016 - Held Jointly with 2016 International Conference on Photonics in Switching, PS 2016, July 3, 2016 - July 7, 2016;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 Department of Physics and Materials Science, City University of Hong Kong, Hong Kong2 Department of Microelectronics, Fuzhou University, Qi Shan Campus, Fuzhou; 350108, China3 State Key Lab of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics, CAS, China
Abstract: We investigate the nonlinear properties of the doped silica glass integrated waveguide platform with a Si-nc strip-loaded structure. We show the nonlinear properties is drastically enhanced by adding a Si-nc layer in the waveguide core. © 2016 IEICE. (17 refs.)Main Heading: Optoelectronic devicesControlled terms: Integrated optics - Nanoclusters - Nonlinear optics - Optical waveguides - Photonics - Silicon - WaveguidesUncontrolled terms: High-index contrast waveguides - Integrated waveguides - Loaded structures - Nonlinear applications - Nonlinear properties - Si nanocrystal - Strip loaded waveguides - Waveguide coreClassification Code: 549.3 Nonferrous Metals and Alloys excluding Alkali and Alkaline Earth Metals Nonferrous Metals and Alloys excluding Alkali and Alkaline Earth Metals - 714.3 WaveguidesWaveguides - 741.1.1 Nonlinear OpticsNonlinear Optics - 741.3 Optical Devices and SystemsOptical Devices and Systems - 761 NanotechnologyNanotechnology - 933 Solid State PhysicsSolid State Physics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Waveguide fabrication in Yb3+doped phosphate glass by 50 kHz repetition rate ultrafast laser
Liu, Xin1, 2; Bai, Jing1; Zhao, Wei1; Cheng, Guanghua1 Source: Journal of Laser Micro Nanoengineering, v 11, n 3, p 321-325, 2016; E-ISSN: 18800688; DOI: 10.2961/jlmn.2016.03.0007;
Publisher: Japan Laser Processing SocietyAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics of CAS, Xi'an; 710119, China2 University of Chinese Academy of Sciences, Beijing; 100049, China
Abstract: Waveguide (trace guiding type) inscription condition inside Yb3+doped phosphate bulk glass was investigated under irradiating of 50 kHz repetition rate volume ultrafast lasers. We processed single trace and multi-core ones inside the bulk material, the captured near field mode pattern confirmed that both structures perform good guiding properties. Beam shaping technique was adopted during fabrication of the single trace in order to obtain a relative symmetric waveguide cross section. Waveguide lasing was achieved in the single line trace with a linear cavity configuration. The maximum laser output of 11 mW was obtained under mono-directional of 980 nm space light pumping, with ~2% corresponding slope efficiency. Guiding mode could be manipulated in the Expanded-core waveguide (ECW) by extra design freedom in the structure parameter, and ECW generally support larger effective mode area light transporting. (22 refs.)Main Heading: Ultrafast lasersControlled terms: Glass - Optical waveguides - Pumping (laser) - Waveguides - YtterbiumUncontrolled terms: Beam shaping technique - Expanded-core - Expanded-core waveguides - Large mode area - Photo-inscription - Symmetric waveguides - Waveguide fabrication - Waveguide lasersClassification Code: 547.2 Rare Earth MetalsRare Earth Metals - 714.3 WaveguidesWaveguides - 744.1 Lasers, GeneralLasers, General - 812.3 GlassGlass
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Numerical simulation of thermo-mechanical behavior in high power diode laser arrays
Lu, Yao1; Nie, Zhiqiang1; Zhang, Pu1; Wang, Zhenfu1; Xiong, Lingling1; Wang, Shuna1; Wu, Dihai1; Liu, Xingsheng2 Source: 2016 17th International Conference on Electronic Packaging Technology, ICEPT 2016, p 76-83, October 4, 2016, 2016 17th International Conference on Electronic Packaging Technology, ICEPT 2016; ISBN-13: 9781509013968; DOI: 10.1109/ICEPT.2016.7583094; Article number: 7583094; Conference: 17th International Conference on Electronic Packaging Technology, ICEPT 2016, August 16, 2016 - August 19, 2016;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics, Shaanxi, China2 Focuslight Technologies Co. LTD, Xi'an, Shaanxi, China
Abstract: Thermal stress is an influential factor for the reliability of HPDL and their optical properties. Two packages of conduction-cooled-packaged 60W HPDL were selected as the study samples. In order to investigate what reflow factors influence thermo-mechanical of HPLD, a COS model is established. In reflow process and working process, hard solder package suffers higher thermal stress. Thermal stress mainly comes from reflow process. In reflow process, copper mount will deteriorate thermo-mechanical of hard solder package. There exists shear stress in HPLD and it will convert TE-polarized power to TM-polarized power. In working process, uniaxial normal stress along the width direction of QW is mainly influenced by coefficient expansion thermal. The displacement of HCS along growth direction is larger than that of CS, whereas the 'smile' value is smaller. 'Smile' is mainly impacted by CTE of solder and submount. © 2016 IEEE. (13 refs.)Main Heading: Semiconductor lasersControlled terms: Computer simulation - Electronics packaging - High power lasers - Numerical models - Occupational risks - Optical properties - Packaging - Power semiconductor diodes - Shear stress - Thermal stressUncontrolled terms: Conduction cooled - Growth directions - High-power diode laser arrays - Influential factors - Reflow process - Thermo-mechanical - Thermo-mechanical behaviors - Working processClassification Code: 694.1 Packaging, GeneralPackaging, General - 723.5 Computer ApplicationsComputer Applications - 741.1 Light/OpticsLight/Optics - 744.1 Lasers, GeneralLasers, General - 744.4.1 Semiconductor LasersSemiconductor Lasers - 921 MathematicsMathematics - 931.2 Physical Properties of Gases, Liquids and SolidsPhysical Properties of Gases, Liquids and Solids
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Scalable Linear Visual Feature Learning via Online Parallel Nonnegative Matrix Factorization
Zhao, Xueyi1; Li, Xi2, 6; Zhang, Zhongfei1, 3; Shen, Chunhua4; Zhuang, Yueting2; Gao, Lixin5; Li, Xuelong2, 6 Source: IEEE Transactions on Neural Networks and Learning Systems, v 27, n 12, p 2628-2642, December 2016
; ISSN: 2162237X, E-ISSN: 21622388; DOI: 10.1109/TNNLS.2015.2499273;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 Department of Information Science and Electronic Engineering, Zhejiang University, Hangzhou; 310027, China2 College of Computer Science, Zhejiang University, Hangzhou; 310027, China3 Computer Science Department, Watson School, State University of New York Binghamton University, Binghamton; NY; 13902, United States4 School of Computer Science, University of Adelaide, Adelaide; SA; 5005, Australia5 University of Massachusetts at Amherst, Amherst; MA; 01003, United States6 Center for OPTical IMagery Analysis and Learning (OPTIMAL), State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, Shaanxi; 710119, China
Abstract: Visual feature learning, which aims to construct an effective feature representation for visual data, has a wide range of applications in computer vision. It is often posed as a problem of nonnegative matrix factorization (NMF), which constructs a linear representation for the data. Although NMF is typically parallelized for efficiency, traditional parallelization methods suffer from either an expensive computation or a high runtime memory usage. To alleviate this problem, we propose a parallel NMF method called alternating least square block decomposition (ALSD), which efficiently solves a set of conditionally independent optimization subproblems based on a highly parallelized fine-grained grid-based blockwise matrix decomposition. By assigning each block optimization subproblem to an individual computing node, ALSD can be effectively implemented in a MapReduce-based Hadoop framework. In order to cope with dynamically varying visual data, we further present an incremental version of ALSD, which is able to incrementally update the NMF solution with a low computational cost. Experimental results demonstrate the efficiency and scalability of the proposed methods as well as their applications to image clustering and image retrieval. © 2015 IEEE. (49 refs.)Main Heading: Matrix algebraControlled terms: E-learning - Efficiency - Factorization - Least squares approximations - Parallel processing systemsUncontrolled terms: Alternating least squares - Feature learning - Feature representation - Individual computing - Linear representation - Matrix decomposition - Nonnegative matrix factorization - On-line algorithmsClassification Code: 722.4 Digital Computers and SystemsDigital Computers and Systems - 913.1 Production EngineeringProduction Engineering - 921 MathematicsMathematics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Research on manufacturing method of CGH
Duan, Xueting1 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 9684, 2016, 8th International Symposium on Advanced Optical Manufacturing and Testing Technology: Optical Test, Measurement Technology, and Equipment
; ISSN: 0277786X, E-ISSN: 1996756X; ISBN-13: 9781628419191; DOI: 10.1117/12.2244164; Article number: 96841T; Conference: 8th International Symposium on Advanced Optical Manufacturing and Testing Technology: Optical Test, Measurement Technology, and Equipment, AOMATT 2016, April 26, 2016 - April 29, 2016; Sponsor: Chinese Academy of Sciences, Institute of Optics and Electronics (IOE); The Chinese Optical Society (COS);
Publisher: SPIEAuthor affiliation: 1 Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China
Abstract: Computer Generated Holograms (CGH) has shown strong application potential and broad application prospect as the more and more extensive application of CGH. With respect to manufacture an available CGH, design the CGH will be easier. Therefore, this paper mainly summarizes some current feasible CGH manufacturing processes, and in this paper, the manufacturing processes of different types of CGH are presented and analyzed. © 2016 SPIE. (4 refs.)Main Heading: Industrial researchControlled terms: Computer generated holography - Manufacture - Optical testingUncontrolled terms: Broad application - Computer generated holograms - Manufacturing methods - Manufacturing processClassification Code: 537.1 Heat Treatment ProcessesHeat Treatment Processes - 723.5 Computer ApplicationsComputer Applications - 741.3 Optical Devices and SystemsOptical Devices and Systems - 901.3 Engineering ResearchEngineering Research
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Two-dimensional photon counting imaging detector based on PCB delay line anode
Zhu, Bingli1; Bai, Yonglin1; Lei, Fanpu1; Bai, Xiaohong1; Wang, Bo1; Qin, Junjun1; Cao, Weiwei1; Gou, Yongsheng1 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 10141, 2016, Selected Papers of the Chinese Society for Optical Engineering Conferences held July 2016
; ISSN: 0277786X, E-ISSN: 1996756X; ISBN-13: 9781510607279; DOI: 10.1117/12.2255682; Article number: 101411A; Conference: 3rd International Symposium on Monitoring, Early Warning, Removal Technology of Space Targets and Debris, the 4th International Conference on Frontiers in Optical Imaging Technology and Applications, and the 2nd International Symposium on Photoelectric Defense Technologies, July 22, 2016 - July 26, 2016; Sponsor: China High-Tech Industrialization Association; Chinese Academy of Engineering; Chinese Society for Optical Engineering; National Natural Science Foundation of China;
Publisher: SPIEAuthor affiliation: 1 Key Laboratory of Ultrafast Photoelectric Diagnostic Technology, Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China
Abstract: Delay line anode detector has high spatial resolution and high count rate. It has been an important technical means for single photon imaging from near earth space to deep space. A two dimensional delay line anode is designed using multilayer circuit board technology. A complete set of PCB delay line anode single photon detection system is established. The spatial resolution of the detector is theoretically analyzed. Moreover, the signal transmission characteristic of PCB delay line and the dark count rate of the detector are tested. Theoretical analysis and experimental results show that the detector spatial resolution is about 100um and the overall dark count rate is 4counts/cm2at 2.3KV. © 2016 SPIE. (12 refs.)Main Heading: Delay circuitsControlled terms: Anodes - Earth (planet) - Electrodes - Image resolution - Imaging techniques - Particle beams - Photons - Printed circuit boards - Space debrisUncontrolled terms: High spatial resolution - Micro channel plate - Multi-layer circuit boards - Photon counting - Photon-counting imaging - Signal transmission - Single photon detection - Single-photon imagingClassification Code: 656.1 Space FlightSpace Flight - 714.1 Electron TubesElectron Tubes - 746 Imaging TechniquesImaging Techniques - 931.3 Atomic and Molecular PhysicsAtomic and Molecular Physics - 932.1 High Energy PhysicsHigh Energy Physics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Multi-channel photonic crystal filters with superposed structure
Shi, Qian1; Zhang, Lei1 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 10154, 2016, Advanced Optical Design and Manufacturing Technology and Astronomical Telescopes and Instrumentation
; ISSN: 0277786X, E-ISSN: 1996756X; DOI: 10.1117/12.2247445; Article number: 1015427; Conference: International Symposium on Advanced Optical Design and Manufacturing Technologies and International Symposium on Astronomical Telescope and Instrumentation, May 9, 2016 - May 11, 2016; Sponsor: China High-Tech Industrialization Association (CHIA); Chinese Society for Optical Engineering (CSOE);
Publisher: SPIEAuthor affiliation: 1 Xi'an Institute of Optics and Precision Mechanics of Cas, University of Chinese Academy of Sciences, Xi'an; 710119, China
Abstract: In this paper, photonic crystal-based filters are proposed. It is different from the narrow band filter with regular channels that Farbry-Perot interference filter and short wave-pass filters are overlapped to the multi-channel photonic crystal filters. The multi-channel photonic crystal filters have two bands in 428nm-449nm of blue light and 535nm-590nm of green light, the average transmittance is over 90%,which are able to meet the requirements of the projection optics. The brightness and color purity of the system are both improved. © 2016 SPIE. (16 refs.)Main Heading: Crystal filtersControlled terms: Bandpass filters - Crystal structure - Fabry-Perot interferometers - Light - Manufacture - Optical design - Photonic crystals - Projection systems - Radio telescopes - Telescopes - Transfer matrix methodUncontrolled terms: Fabry-Perot interference filter - Interference filters - Multi channel - Narrow band filter - One dimensional photonic crystal - Projection optics - Regular channels - Shortwave pass filterClassification Code: 537.1 Heat Treatment ProcessesHeat Treatment Processes - 657.2 Extraterrestrial Physics and Stellar PhenomenaExtraterrestrial Physics and Stellar Phenomena - 703.2 Electric FiltersElectric Filters - 741.1 Light/OpticsLight/Optics - 742.2 Photographic EquipmentPhotographic Equipment - 921 MathematicsMathematics - 933.1.1 Crystal LatticeCrystal Lattice - 941.3 Optical InstrumentsOptical Instruments
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Non-uniform sampling knife-edge method for camera modulation transfer function measurement
Duan, Yaxuan1, 2; Xue, Xun1; Chen, Yongquan1; Tian, Liude1, 2; Zhao, Jianke1; Gao, Limin1 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 10023, 2016, Optical Metrology and Inspection for Industrial Applications IV
; ISSN: 0277786X, E-ISSN: 1996756X; ISBN-13: 9781510604650; DOI: 10.1117/12.2245840; Article number: 100231C; Conference: Conference on Optical Metrology and Inspection for Industrial Applications IV, October 12, 2016 - October 14, 2016; Sponsor: Chinese Optical Society (COS); The Society of Photo-Optical Instrumentation Engineers (SPIE);
Publisher: SPIEAuthor affiliation: 1 Axi'An Institute of Optics and Precision Mechanics, Chinese Academy of Science, Xi'an, Shaanxi; 710119, China2 University of Chinese Academy of Sciences, Beijing; 100049, China
Abstract: Traditional slanted knife-edge method experiences large errors in the camera modulation transfer function (MTF) due to tilt angle error in the knife-edge resulting in non-uniform sampling of the edge spread function. In order to resolve this problem, a non -uniform sampling knife-edge method for camera MTF measurement is proposed. By applying a simple direct calculation of the Fourier transform of the derivative for the non-uniform sampling data, the camera super-sampled MTF results are obtained. Theoretical simulations for images with and without noise under different tilt angle errors are run using the proposed method. It is demonstrated that the MTF results are insensitive to tilt angle errors. To verify the accuracy of the proposed method, an experimental setup for camera MTF measurement is established. Measurement results show that the proposed method is superior to traditional methods, and improves the universality of the slanted knife-edge method for camera MTF measurement. © 2016 SPIE. (18 refs.)Main Heading: Optical transfer functionControlled terms: Cameras - Errors - Measurements - Modulation - Transfer functions - Units of measurementUncontrolled terms: Direct calculation - Edge spread function - Knife edge - Modulation transfer function measurements - Nonuniform sampling - Numerical approximation and analysis - Slanted Knife-Edge - Theoretical simulationClassification Code: 741.1 Light/OpticsLight/Optics - 742.2 Photographic EquipmentPhotographic Equipment - 902.2 Codes and StandardsCodes and Standards - 921 MathematicsMathematics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Stepless digital zoom for high definition camera
Guo, Huinan1; Fang, Yao1; Liu, Qing1; Zhang, Hui1; Ma, Nan2; Duan, Baosong3 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 10033, 2016, Eighth International Conference on Digital Image Processing, ICDIP 2016
; ISSN: 0277786X, E-ISSN: 1996756X; ISBN-13: 9781510605039; DOI: 10.1117/12.2245155; Article number: 100334E; Conference: 8th International Conference on Digital Image Processing, ICDIP 2016, May 20, 2016 - May 23, 2016; Sponsor: Chengdu University of Information Technology; Chinese Academy of Sciences Chengdu Institute of Computer Applications; International Association of Computer Science and Information Technology; Sichuan Province Computer Federation;
Publisher: SPIEAuthor affiliation: 1 Xi'An Institute of Optics and Precision Mechanics of CAS, No.17, Xinxi Rd, Xi'an, Shaanxi, China2 People's Liberation Army of No.95879, Chengdu, Sichuan, China3 Xi'An Communications Institute, No.5, Guangming Rd, Changan district, Xi'an, Shaanxi, China
Abstract: Real-time full frame view of surveillance camera provides integral visual information of scene. High definition imaging and zooming are widely adopted when observers want to capture more detail information of targets. The optical zooming can provide high zoom ratio detail images of target as well as maintain imaging definition, however, it fails to obtain full view of scene when zoomed, and the field of observation decreases to region of target. Digital zooming is an effective approach to keep the balance between imaging field and visual detail information. This paper presents a method of stepless zooming for digital video camera which could be widely used in autonomous pan, tilt and zoom surveillance system. In view of hardware resources and algorithm realizability, an optimized zooming processing structure is proposed. According to input zoom ratio parameter, it can extract pixels of region of interest adaptively and display with original imaging size by mapping and interpolation algorithms. Experimental results indicate that the stepless zooming method can be capable of achieving 1080p high definition imaging and 30 frame/s video capture. © 2016 SPIE. (10 refs.)Main Heading: Image processingControlled terms: Computational complexity - Computer graphics - Digital cameras - Image segmentation - Monitoring - Multimedia systems - Optical data processing - Security systems - Space surveillance - Video camerasUncontrolled terms: Digital video cameras - Effective approaches - High definition imaging - Interpolation algorithms - Region of interest - Surveillance cameras - Surveillance systems - ZoomClassification Code: 656.2 Space ResearchSpace Research - 721.1 Computer Theory, Includes Formal Logic, Automata Theory, Switching Theory, Programming TheoryComputer Theory, Includes Formal Logic, Automata Theory, Switching Theory, Programming Theory - 723.2 Data Processing and Image ProcessingData Processing and Image Processing - 723.5 Computer ApplicationsComputer Applications - 742.2 Photographic EquipmentPhotographic Equipment - 914.1 Accidents and Accident PreventionAccidents and Accident Prevention
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Computer-Aided alignment method of optical lens with high accuracy
Xing, Song1; Hou, Xiao-Hua1; Zhang, Xue-Min1; Ji, Bin-Dong2 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 9684, 2016, 8th International Symposium on Advanced Optical Manufacturing and Testing Technology: Optical Test, Measurement Technology, and Equipment
; ISSN: 0277786X, E-ISSN: 1996756X; ISBN-13: 9781628419191; DOI: 10.1117/12.2245129; Article number: 968440; Conference: 8th International Symposium on Advanced Optical Manufacturing and Testing Technology: Optical Test, Measurement Technology, and Equipment, AOMATT 2016, April 26, 2016 - April 29, 2016; Sponsor: Chinese Academy of Sciences, Institute of Optics and Electronics (IOE); The Chinese Optical Society (COS);
Publisher: SPIEAuthor affiliation: 1 Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China2 Graduate University of Chinese Academy of Sciences, Beijing; 100049, China
Abstract: With the development of space and aviation industry, the optical systems with high resolution and better imaging quality are required. According to the alignment technical process, the factors of every step which have big influence to the imaging quality are analyzed. It is detected that the micro-stress assembly of the optical unit and the high co-Axial precision of the entire optical system are the two important factors which are supposed to determine how well the imaging quality of the optical system is; also the technical methods are discussed to ensure these two factors from the engineering view. The reflective interference testing method to measure the surface figure and the transitive interference testing method to measure the wave aberration of the optical unit are combined to ensure the micro-stress assembly of the optical unit, so it will not bring astigmatism to the whole system imaging quality. Optical alignment machining and precision alignment are combined to ensure the high co-Axial precision of the optical system. An optical lens of high accuracy is assembled by using these methods; the final wave aberration of optical lens is 0.022λ. © 2016 SPIE. (9 refs.)Main Heading: LensesControlled terms: Manufacture - Optical instrument lenses - Optical systems - Optical testing - Precision engineeringUncontrolled terms: Computer-aided alignment - Computer-aided alignment method - High-accuracy - Interference testing - Optical alignment machining - Optical lens - Precision alignment - Reflective interferencesClassification Code: 537.1 Heat Treatment ProcessesHeat Treatment Processes - 741.3 Optical Devices and SystemsOptical Devices and Systems
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Perception-inspired background subtraction in complex scenes based on spatiotemporal features
Shi, Liu1, 2; Liu, Jiahang1 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 10157, 2016, Infrared Technology and Applications, and Robot Sensing and Advanced Control
; ISSN: 0277786X, E-ISSN: 1996756X; ISBN-13: 9781510607729; DOI: 10.1117/12.2244151; Article number: 101570C; Conference: International Symposium on Infrared Technology and Application and the International Symposiums on Robot Sensing and Advanced Control, May 9, 2016 - May 11, 2016; Sponsor: China High-Tech Industrialization Association (CHIA); Chinese Society for Optical Engineering (CSOE);
Publisher: SPIEAuthor affiliation: 1 Xi'an Institute of Optics and Precision Mechanics of CAS, Xi'an; 710119, China2 University of Chinese, Academy of Sciences, Beijing; 100049, China
Abstract: Background subtraction (BGS) is a fundamental preprocessing step in most video-based applications. Most BGS methods fail to handle dynamic unconstrained scenarios accurately. This is because of overreliance on statistical model. In this paper, we develop a novel non-parametric sample-based background subtraction method. First, the background sample set is initialized by a clean sample frame rather than the first frame. This can avoid introducing a ghost when the first frame contains foreground objects. Here, we utilize the Gaussian mixture model to validate whether a pixel at the location is clean or not and construct the initialization of background model. Second, for an actual scenario with diversified environmental conditions (e.g., illumination changes, dynamic background), we employ normalized color space and a scale invariant local ternary pattern operator to handle these variations. In the meantime, in order to achieve high detection accuracy in the unconstrained scenarios without requiring any scenario-specific parameter tuning, we employ the perception-inspired confidence interval to modify the threshold in the color space. Third, the hole filling approach is used to reduce noise which comes from false segmentation, fill the blank area in the foreground region and maintain the integrity of foreground object. Our experimental results indicate that the proposed approach is superior to several state-of-the-art methods in terms of F-score and kappa index. © 2016 SPIE. (16 refs.)Main Heading: Object recognitionControlled terms: Color - Gaussian distribution - Image segmentation - Infrared radiation - Object detection - Security systemsUncontrolled terms: Background subtraction - Background subtraction method - Environmental conditions - Local ternary patterns - Moving-object detection - Spatio temporal features - State-of-the-art methods - Video surveillanceClassification Code: 723.2 Data Processing and Image ProcessingData Processing and Image Processing - 741.1 Light/OpticsLight/Optics - 914.1 Accidents and Accident PreventionAccidents and Accident Prevention - 922.1 Probability TheoryProbability Theory
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Parameter-free auto-weighted multiple graph learning: A framework for multiview clustering and semi-supervised classification
Nie, Feiping1; Li, Jing1; Li, Xuelong2 Source: IJCAI International Joint Conference on Artificial Intelligence, v 2016-January, p 1881-1887, 2016, Proceedings of the 25th International Joint Conference on Artificial Intelligence, IJCAI 2016
; ISSN: 10450823; Conference: 25th International Joint Conference on Artificial Intelligence, IJCAI 2016, July 9, 2016 - July 15, 2016; Sponsor: AI Journal; Arizona State University; Baidu; et al.; IBM Watson; Sony;
Publisher: International Joint Conferences on Artificial IntelligenceAuthor affiliation: 1 School of Computer Science, Center for OPTical IMagery Analysis and Learning (OPTIMAL), Northwestern Polytechnical University, Xi'an; 710072, China2 Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China
Abstract: Graph-based approaches have been successful in unsupervised and semi-supervised learning. In this paper, we focus on the real-world applications where the same instance can be represented by multiple heterogeneous features. The key point of utilizing the graph-based knowledge to deal with this kind of data is to reasonably integrate the different representations and obtain the most consistent manifold with the real data distributions. In this paper, we propose a novel framework via the reformulation of the standard spectral learning model, which can be used for multiview clustering and semisupervised tasks. Unlike other methods in the literature, the proposed methods can learn an optimal weight for each graph automatically without introducing an additive parameter as previous methods do. Furthermore, our objective under semisupervised learning is convex and the global optimal result will be obtained. Extensive empirical results on different real-world data sets demonstrate that the proposed methods achieve comparable performance with the state-of-the-art approaches and can be used more practically. (24 refs.)Main Heading: Supervised learningControlled terms: Artificial intelligence - Graphic methods - Learning algorithms - Virtual realityUncontrolled terms: Data distribution - Heterogeneous features - Multi-view clustering - Semi- supervised learning - Semi-supervised - Semi-supervised classification - Spectral learning - State-of-the-art approachClassification Code: 723 Computer Software, Data Handling and ApplicationsComputer Software, Data Handling and Applications - 723.4 Artificial IntelligenceArtificial Intelligence
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Reflectivity and depth images based on time-correlated single photon counting technique
Duan, Xuejie1; Ma, Lin1; Kang, Yan2; Zhang, Tongyi2 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 10155, 2016, Optical Measurement Technology and Instrumentation
; ISSN: 0277786X, E-ISSN: 1996756X; ISBN-13: 9781510607682; DOI: 10.1117/12.2247242; Article number: 101552X; Conference: International Symposium on Optical Measurement Technology and Instrumentation, May 9, 2016 - May 11, 2016; Sponsor: China High-Tech Industrialization Association (CHIA); Chinese Society for Optical Engineering (CSOE);
Publisher: SPIEAuthor affiliation: 1 Xidian University, No.2 South Taibai Road, Xi'an; 710071, China2 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics of CAS, No.17 Xinxi Avenue, Xi'an; 710119, China
Abstract: We presented three-dimensional image including reflectivity and depth image of a target with two traditional optical imaging systems based on time-correlated single photon counting technique (TCSPC), when it was illuminated by a MHz repetition rate pulsed laser source. The first one is bi-static system of which transmitted and received beams path are separated. Another one called mono-static system of which transmit and receive channels are coaxial, so it was also named by transceiver system. Experimental results produced by both systems showed that the mono-static system had more advantages of less noise from ambient light and no limitation about field area of view. While in practical applications, the target was far away leading to there were few photons return which was prejudicial to build 3D images with traditional imaging system. Thus an advanced one named first photon system was presented. This one was also a mono-static system on hardware system structure, but the control system structure was different with traditional transceiver system described in this paper. The difference was that the first return photon per pixel was recorded across system with first photon system, instead of overall return photons per pixel. That's to say only one detected return photon is needed for per pixel of this system to rebuild 3D images of target with less energy and time. © 2016 SPIE. (22 refs.)Main Heading: PhotonsControlled terms: Imaging systems - Optical data processing - Optical variables measurement - Particle beams - Pixels - Reflection - Structured programming - TransceiversUncontrolled terms: 3-D image - Control system structure - First photon system - Mono-static - Optical imaging system - TCSPC - Three dimensional images - Time-correlated single photon counting techniquesClassification Code: 716.3 Radio Systems and EquipmentRadio Systems and Equipment - 723.1 Computer ProgrammingComputer Programming - 723.2 Data Processing and Image ProcessingData Processing and Image Processing - 746 Imaging TechniquesImaging Techniques - 931.3 Atomic and Molecular PhysicsAtomic and Molecular Physics - 932.1 High Energy PhysicsHigh Energy Physics - 941.4 Optical Variables MeasurementsOptical Variables Measurements
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


MoS2-mode-locked fiber laser delivering ultrashort pulses with three types of sidebands
Lu, Feifei1; Liu, Xueming1; Yang, Huiran1 Source: Optics InfoBase Conference Papers, August 29, 2016, Bragg Gratings, Photosensitivity, and Poling in Glass Waveguides, BGPP 2016; ISBN-13: 9781943580170; DOI: 10.1364/BGPP.2016.JM6A.1; Conference: Bragg Gratings, Photosensitivity, and Poling in Glass Waveguides, BGPP 2016, September 5, 2016 - September 8, 2016; Sponsor: American Elements; Australian Optical Society; cudos; Modular Photonics; OSA;
Publisher: OSA - The Optical SocietyAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, 710119, China
Abstract: We demonstrate an erbium-doped fiber laser passively mode-locked by a monolayer MoS2which is covered onto a fiber taper. Three types of sidebands, e.g. peak, peak-dip and dip spectral sidebands, are observed in the experiment. © OSA 2016. (6 refs.)Main Heading: Mode-locked fiber lasersControlled terms: Bragg gratings - Fiber lasers - Glass - Light sensitive materials - Molybdenum compounds - Passive mode locking - Photosensitivity - Ultrashort pulses - WaveguidesUncontrolled terms: Erbium doped fiber laser - Fiber taper - Passively mode-locked - Spectral sidebandsClassification Code: 714.3 WaveguidesWaveguides - 741.1 Light/OpticsLight/Optics - 741.3 Optical Devices and SystemsOptical Devices and Systems - 744.1 Lasers, GeneralLasers, General - 744.4 Solid State LasersSolid State Lasers - 812.3 GlassGlass
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


A Local Structural Descriptor for Image Matching via Normalized Graph Laplacian Embedding
Tang, Jun1; Shao, Ling2; Li, Xuelong3; Lu, Ke4, 5 Source: IEEE Transactions on Cybernetics, v 46, n 2, p 410-420, February 2016
; ISSN: 21682267; DOI: 10.1109/TCYB.2015.2402751; Article number: 7056508;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 Key Laboratory of Intelligent Computing and Signal Processing, Ministry of Education, Anhui University, Hefei, China2 Department of Computer Science and Digital Technologies, Northumbria University, Newcastle upon Tyne, United Kingdom3 Center for OPTical IMagery Analysis and Learning (OPTIMAL), State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Xi'an, China4 University of Chinese Academy of Sciences, Beijing, China5 Beijing Center for Mathematics and Information Interdisciplinary Sciences, Beijing, China
Abstract: This paper investigates graph spectral approaches to the problem of point pattern matching. Specifically, we concentrate on the issue of how to effectively use graph spectral properties to characterize point patterns in the presence of positional jitter and outliers. A novel local spectral descriptor is proposed to represent the attribute domain of feature points. For a point in a given point-set, weight graphs are constructed on its neighboring points and then their normalized Laplacian matrices are computed. According to the known spectral radius of the normalized Laplacian matrix, the distribution of the eigenvalues of these normalized Laplacian matrices is summarized as a histogram to form a descriptor. The proposed spectral descriptor is finally combined with the approximate distance order for recovering correspondences between point-sets. Extensive experiments demonstrate the effectiveness of the proposed approach and its superiority to the existing methods. © 2013 IEEE. (46 refs.)Main Heading: Laplace transformsControlled terms: Eigenvalues and eigenfunctions - Geometry - Image matching - Matrix algebra - Pattern matchingUncontrolled terms: Graph-spectral approach - Neighboring point - Normalized graph Laplacian - Normalized Laplacian - Point pattern matching - Point patterns - Spectral properties - Structural descriptor
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Principal Component 2-D Long Short-Term Memory for Font Recognition on Single Chinese Characters
Tao, Dapeng1; Lin, Xu2; Jin, Lianwen2; Li, Xuelong3 Source: IEEE Transactions on Cybernetics, v 46, n 3, p 756-765, March 2016
; ISSN: 21682267; DOI: 10.1109/TCYB.2015.2414920; Article number: 7073574;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 School of Information Science and Engineering, Yunnan University, Kunming, China2 School of Electronic and Information Engineering, South China University of Technology, Guangzhou, China3 Center for OPTical IMagery Analysis and Learning (OPTIMAL), State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, Shaanxi, China
Abstract: Chinese character font recognition (CCFR) has received increasing attention as the intelligent applications based on optical character recognition becomes popular. However, traditional CCFR systems do not handle noisy data effectively. By analyzing in detail the basic strokes of Chinese characters, we propose that font recognition on a single Chinese character is a sequence classification problem, which can be effectively solved by recurrent neural networks. For robust CCFR, we integrate a principal component convolution layer with the 2-D long short-term memory (2DLSTM) and develop principal component 2DLSTM (PC-2DLSTM) algorithm. PC-2DLSTM considers two aspects: 1) the principal component layer convolution operation helps remove the noise and get a rational and complete font information and 2) simultaneously, 2DLSTM deals with the long-range contextual processing along scan directions that can contribute to capture the contrast between character trajectory and background. Experiments using the frequently used CCFR dataset suggest the effectiveness of PC-2DLSTM compared with other state-of-the-art font recognition methods. © 2015 IEEE. (59 refs.)Main Heading: Principal component analysisControlled terms: Brain - Character recognition - Convolution - Optical character recognition - Recurrent neural networksUncontrolled terms: Chinese characters - Font recognition - Intelligent applications - Long short term memory - Principal Components - Scan direction - Sequence classification - State of the art
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Efficient and Robust Learning for Sustainable and Reacquisition-Enabled Hand Tracking
Abdul Aziz, Muhammad Ali1; Niu, Jianwei1; Zhao, Xiaoke1; Li, Xuelong2 Source: IEEE Transactions on Cybernetics, v 46, n 4, p 945-958, April 2016
; ISSN: 21682267; DOI: 10.1109/TCYB.2015.2418275; Article number: 7088593;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 State Key Laboratory of Virtual Reality Technology and Systems, School of Computer Science and Engineering, Beihang University, Beijing, China2 Center for Optical Imagery Analysis and Learning, State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, China
Abstract: The use of machine learning approaches for long-term hand tracking poses some major challenges such as attaining robustness to inconsistencies in lighting, scale and object appearances, background clutter, and total object occlusion/disappearance. To address these issues in this paper, we present a robust machine learning approach based on enhanced particle filter trackers. The inherent drawbacks associated with the particle filter approach, i.e., sample degeneration and sample impoverishment, are minimized by infusing the particle filter with the mean shift approach. Moreover, to instill our tracker with reacquisition ability, we propose a rotation invariant and efficient detection framework named beta histograms of oriented gradients. Our robust appearance model operates on the red, green, blue color histogram and our newly proposed rotation invariant noise compensated local binary patterns descriptor, which is a noise compensated, rotation invariant version of the local binary patterns descriptor. Through our experiments, we demonstrate that our proposed hand tracker performs favorably against state-of-the-art algorithms on numerous challenging video sequences of hand postures, and overcomes the largely unsolved problem of redetecting hands after they vanish and reappear into the frame. © 2015 IEEE. (55 refs.)Main Heading: Palmprint recognitionControlled terms: Artificial intelligence - Graphic methods - Learning systems - Monte Carlo methods - Statistical methodsUncontrolled terms: Appearance modeling - Efficient detection - Histograms of oriented gradients - Local binary patterns - Machine learning approaches - Particle filter trackers - Sample impoverishment - State-of-the-art algorithms
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Relevance and irrelevance graph based marginal Fisher analysis for image search reranking
Ji, Zhong1; Pang, Yanwei1; Yuan, Yuan2; Pan, Jing3 Source: Signal Processing, v 121, p 139-152, April 2016
; ISSN: 01651684; DOI: 10.1016/j.sigpro.2015.11.010;
Publisher: ElsevierAuthor affiliation: 1 School of Electronic Information Engineering, Tianjin University, Tianjin, China2 Center for Optical Imagery Analysis and Learning (OPTIMAL), State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, China3 School of Electronic Engineering, Tianjin University of Technology and Education, Tianjin, China
Abstract: Learning-to-rank techniques have shown promising results in the domain of image ranking recently, where dimensionality reduction is a critical step to overcome the "curse of dimensionality". However, conventional dimensionality reduction approaches cannot guarantee the satisfying performance because the important ranking information is ignored. This paper presents a novel "Ranking Dimensionality Reduction" scheme specifically designed for learning-to-rank based image ranking, which aims at not only discovering the intrinsic structure of data but also keeping the ordinal information. Within this scheme, a new dimensionality reduction algorithm called Relevance Marginal Fisher Analysis (RMFA) is proposed. RMFA models the proposed pairwise constraints of relevance-link and irrelevance-link into the relevance graph and the irrelevance graph, and applies the graphs to build the objective function with the idea of Marginal Fisher Analysis (MFA). Further, a semi-supervised RMFA algorithm called Semi-RMFA is developed to offer a more general solution for the real-world application. Extensive experiments are carried on two popular, real-world image search reranking datasets. The promising results demonstrate the robustness and effectiveness of the proposed scheme and methods. © 2015 Elsevier B.V. (42 refs.)Main Heading: Search enginesControlled terms: Graphic methods - Image analysisUncontrolled terms: Dimensionality reduction - Image rankings - Image search reranking - Learning to rank - Marginal fisher analysis - MultiMedia Information SystemsClassification Code: 723 Computer Software, Data Handling and ApplicationsComputer Software, Data Handling and Applications
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Analysis of dual-end-pumped Nd3+-doped index-crossover gain guided-index antiguided fiber laser
Shen, Xiao1, 2; Wei, Wei1; Zou, Hui1; Zhang, Liaolin1 Source: Optics Communications, v 366, p 205-209, May 1, 2016
; ISSN: 00304018; DOI: 10.1016/j.optcom.2015.12.063;
Publisher: ElsevierAuthor affiliation: 1 College of Optoelectronic Engineering, Nanjing University of Posts and Telecommunications, Nanjing, Jiangsu, China2 State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xian, Shanxi, China
Abstract: A dual-end pumped Nd3+-doped index-crossover gain guided-index antiguided (IGG-IAG) fiber laser is analyzed in theory. Pump light propagation and output laser characteristics are both explored by solving the related rate equations. Simulation results show that pump power confined in the IGG-IAG fiber core is larger and more uniform than that of the gain-guided and index-antiguided(GG-IAG) fiber, and the optimum fiber length and the output power of the IGG-IAG fiber laser are both larger than that of GG-IAG fiber laser. The relationship between threshold pump power and doped concentration, fiber length, fiber radius is researched respectively. The analysis results give out a method for the optimal design of the IGG-IAG fiber laser. © 2015 Elsevier B.V. All rights reserved. (15 refs.)Main Heading: Pumping (laser)Controlled terms: Fiber lasers - Fibers - Laser theoryUncontrolled terms: Gain-guided index antiguided fibers - Index antiguided - Laser characteristics - Optimal design - Optimum fiber length - Pump power distribution - Rate equations - Threshold pump powerClassification Code: 744.1 Lasers, GeneralLasers, General - 744.4 Solid State LasersSolid State Lasers
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Impact of light polarization on the measurement of water particulate backscattering coefficient
Liu, Jia1, 2; Gong, Fang1; He, Xian-Qiang1; Zhu, Qian-Kun1; Huang, Hai-Qing1 Source: Guang Pu Xue Yu Guang Pu Fen Xi/Spectroscopy and Spectral Analysis, v 36, n 1, p 31-37, January 1, 2016; Language: Chinese
; ISSN: 10000593; DOI: 10.3964/j.issn.1000-0593(2016)01-0031-07;
Publisher: Science PressAuthor affiliation: 1 State Key Laboratory of Satellite Ocean Environment Dynamics, Second Institute of Oceanography, State Oceanic Administration, Hangzhou, China2 Laboratory of Remote Sensing and Intelligent Information System, Xi'an Institute of Optics and Precision Mechanics of Chinese Academy of Sciences, Xi'an, China
Abstract: Particulate backscattering coefficient is a main inherent optical properties (IOPs) of water, which is also a determining factor of ocean color and a basic parameter for inversion of satellite ocean color remote sensing. In-situ measurement with optical instruments is currently the main method for obtaining the particulate backscattering coefficient of water. Due to reflection and refraction by the mirrors in the instrument optical path, the emergent light source from the instrument may be partly polarized, thus to impact the measurement accuracy of water backscattering coefficient. At present, the light polarization of measuring instruments and its impact on the measurement accuracy of particulate backscattering coefficient are still poorly known. For this reason, taking a widely used backscattering coefficient measuring instrument HydroScat6 (HS-6) as an example in this paper, the polarization characteristic of the emergent light from the instrument was systematically measured, and further experimental study on the impact of the light polarization on the measurement accuracy of the particulate backscattering coefficient of water was carried out. The results show that the degree of polarization(DOP) of the central wavelength of emergent light ranges from 20% to 30% for all of the six channels of the HS-6, except the 590 nm channel from which the DOP of the emergent light is slightly low (~15%). Therefore, the emergent light from the HS-6 has significant polarization. Light polarization has non-neglectable impact on the measurement of particulate backscattering coefficient, and the impact degree varies with the wave band, linear polarization angle and suspended particulate matter(SPM) concentration. At different SPM concentrations, the mean difference caused by light polarization can reach 15.49%, 11.27%, 12.79%, 14.43%, 13.76%, and 12.46% in six bands, 420, 442, 470, 510, 590, and 670 nm, respectively. Consequently, the impact of light polarization on the measurement of particulate backscattering coefficient with an optical instrument should be taken into account, and the DOP of the emergent light should be reduced as much as possible. © 2016, Science Press. All right reserved. (19 refs.)Main Heading: BackscatteringControlled terms: Color - Light polarization - Light sources - Optical instruments - Optical properties - Polarization - Remote sensingUncontrolled terms: Backscattering coefficients - Degree of polarization - Inherent optical properties - Inherent optical properties (IOPs) - Ocean color remote sensing - Polarization characteristics - Reflection and refractions - Suspended particulate mattersClassification Code: 741.1 Light/OpticsLight/Optics - 941.3 Optical InstrumentsOptical Instruments
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Ultra-high Q one-dimensional hybrid PhC-SPP waveguide microcavity with large structure tolerance
Liu, Feng1; Zhang, Lingxuan1, 2, 3; Lu, Xiaoyuan1, 3; Wang, Weiqiang1; Wang, Leiran1; Wang, Guoxi1, 2; Zhang, Wenfu1, 2; Zhao, Wei1, 2 Source: Journal of Modern Optics, v 63, n 12, p 1158-1165, July 3, 2016
; ISSN: 09500340, E-ISSN: 13623044; DOI: 10.1080/09500340.2015.1130272;
Publisher: Taylor and Francis Ltd.Author affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics (XIOPM), Chinese Academy of Sciences (CAS), Xi'an, China2 China-U.K. Joint Research Center of Micro/Nano Photonics, XIOPM, CAS, Xi'an, China3 University of Chinese Academy of Sciences, Beijing, China
Abstract: A photonic crystal - surface plasmon-polaritons hybrid transverse magnetic mode waveguide based on a one-dimensional optical microcavity is designed to work in the communication band. A Gaussian field distribution in a stepping heterojunction taper is designed by band engineering, and a silica layer compresses the mode field to the subwavelength scale. The designed microcavity possesses a resonant mode with a quality factor of 1609 and a modal volume of 0.01 cubic wavelength. The constant period and the large structure tolerance make it realizable by current processing techniques. © 2016 Taylor & Francis. (29 refs.)Main Heading: Crystal structureControlled terms: Electromagnetic wave polarization - Heterojunctions - Microcavities - Optical communication - Particle optics - Phonons - Photonic crystals - Photons - Plasmons - Quantum theory - Surface plasmon resonance - WaveguidesUncontrolled terms: Band engineering - Communication bands - Current processing - Large structures - Optical microcavities - Subwavelength scale - Surface plasmon polaritons - Transverse magnetic modes
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


PH-dependent morphology and its effect on the optical properties of LaF3:Nd nanocrystals
Cui, Xiaoxia1; Guo, Haitao1; Wei, Wei1, 2; Hou, Chaoqi1; Gao, Fei1; Peng, Bo1, 2 Source: Materials Chemistry and Physics, v 173, p 132-138, April 15, 2016
; ISSN: 02540584; DOI: 10.1016/j.matchemphys.2016.01.048;
Publisher: Elsevier LtdAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Science (CAS) xi'An Shaanxi, 710119, China2 Institute of Advanced Materials, Nanjing University of Posts and Telecommunications, Nanjing; 210003, China
Abstract: Nd3+-doped LaF3nanocrystals with different morphologies have been produced via solvothermal method at various pH values (1-6). Their morphologies and optical properties were characterized by TEM, fluorescence spectra and decay curves. A possible formation mechanism including burst-nucleation and growth process was proposed. The results reveal that when the pH increases from 1 to 2 to 4-6, the nanocrystals' mean size reduces slightly and the morphologies transform from the hollow sphere to the packed hexagon. The fluorescence lifetime and quantum efficiency achieved maximum for the samples synthesized at pH = 2. These nanocrystals with small size (<30 nm) and bright photoluminescence are promising phosphors in the applications of biological, optical amplifiers and liquid laser fields. © 2016 Elsevier B.V. (29 refs.)Main Heading: Optical propertiesControlled terms: Fluorescence - Light amplifiers - Liquid lasers - Morphology - Nanocrystals - Nanostructures - Optical materials - Surface propertiesUncontrolled terms: Decay curves - Fluorescence lifetimes - Fluorescence spectra - Formation mechanism - Hollow sphere - Nucleation and growth - PH-dependent - Solvothermal method
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Biomimetic microchannels of planar reactors for optimized photocatalytic efficiency of water purification
Liao, Wuxia1, 2; Wang, Ning3, 4; Wang, Taisheng1; Xu, Jia1; Han, Xudong1; Liu, Zhenyu1; Zhang, Xuming3, 4; Yu, Weixing5 Source: Biomicrofluidics, v 10, n 1, January 01, 2016
; ISSN: 19321058; DOI: 10.1063/1.4942947; Article number: 014123;
Publisher: American Institute of Physics Inc.Author affiliation: 1 State Key Laboratory of Applied Optics, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, No. 3888, Dongnanhu Road, Changchun, Jilin, China2 University of the Chinese Academy of Sciences, Beijing, China3 Shenzhen Research Institute, The Hong Kong Polytechnic University, Shenzhen, China4 Department of Applied Physics, Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong5 Key Laboratory of Spectral Imaging Technology, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, No. 17, Xinxi Road, Xian, China
Abstract: This paper reports a biomimetic design of microchannels in the planar reactors with the aim to optimize the photocatalytic efficiency of water purification. Inspired from biology, a bifurcated microchannel has been designed based on the Murray's law to connect to the reaction chamber for photocatalytic reaction. The microchannels are designed to have a constant depth of 50 μm but variable aspect ratios ranging from 0.015 to 0.125. To prove its effectiveness for photocatalytic water purification, the biomimetic planar reactors have been tested and compared with the non-biomimetic ones, showing an improvement of the degradation efficiency by 68%. By employing the finite element method, the flow process of the designed microchannel reactors has been simulated and analyzed. It is found that the biomimetic design owns a larger flow velocity fluctuation than that of the non-biomimetic one, which in turn results in a faster photocatalytic reaction speed. Such a biomimetic design paves the way for the design of more efficient planar reactors and may also find applications in other microfluidic systems that involve the use of microchannels. © 2016 AIP Publishing LLC. (17 refs.)Main Heading: MicrochannelsControlled terms: Aspect ratio - Biomimetics - Degradation - Design - Efficiency - Finite element method - Flow velocity - Microfluidics - Purification - Water treatment plantsUncontrolled terms: Biomimetic design - Degradation efficiency - Micro channel reactors - Micro fluidic system - Photocatalytic efficiency - Photocatalytic reactions - Velocity fluctuations - Water purificationClassification Code: 445.1 Water Treatment TechniquesWater Treatment Techniques - 461.8 BiotechnologyBiotechnology - 631 Fluid FlowFluid Flow - 632.5.1 MicrofluidicsMicrofluidics - 802.2 Chemical ReactionsChemical Reactions - 913.1 Production EngineeringProduction Engineering - 921.6 Numerical MethodsNumerical Methods
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Passively Q-switched nd:YAG laser via a WS2saturable absorber
Wang, Xi1; Wang, Yonggang1; Duan, Lina1; Li, Lu1; Sun, Hang1 Source: Optics Communications, v 367, p 234-238, May 15, 2016
; ISSN: 00304018; DOI: 10.1016/j.optcom.2016.01.066;
Publisher: ElsevierAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, China
Abstract: In this work, we report a passively Q-switched Nd:YAG laser at 1064 nm by using WS2solution as the saturable absorber (SA). The WS2solution with different concentrations (0.25, 0.5, and 1 mg/ml) were fabricated by the liquid-phase-exfoliated method and injected into quartz cells. Such liquid absorbers have the virtues of adjustable optical absorption, high heat dissipation and non-contact damage. By inserting those WS2solutions in the laser cavity, stable Q-switched laser operations were obtained. The corresponding pulse duration as short as 922 ns was obtained. The result shows that the WS2material can be act as absorber for solid-state lasers. © 2016 Elsevier B.V. All rights reserved. (44 refs.)Main Heading: Neodymium lasersControlled terms: Electromagnetic wave absorption - Light absorption - Q switched lasers - Q switching - Saturable absorbers - Solid state lasersUncontrolled terms: 140.3540 - 140.3580 - Liquid Phase - Non-contact - Ocis codes - Passively Q-switched - Pulse durations - Quartz cellsClassification Code: 711 Electromagnetic WavesElectromagnetic Waves - 741.1 Light/OpticsLight/Optics - 744 LasersLasers
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Analysis of the influence of nanofissure morphology on the performance of surface-conduction electron emitters
Shen, Zhihua1; Wang, Xiao1; Wu, Shengli1; Tian, JinShou2 Source: Journal of Micromechanics and Microengineering, v 26, n 4, March 11, 2016
; ISSN: 09601317, E-ISSN: 13616439; DOI: 10.1088/0960-1317/26/4/045011; Article number: 045011;
Publisher: Institute of Physics PublishingAuthor affiliation: 1 Key Laboratory for Physical Electronics and Devices, Ministry of Education, Xi'An Jiaotong University, Xi'an, China2 State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics of CAS, Xi'an, China
Abstract: A simulation model was built to numerically investigate the electron emission property of a new surface-conduction electron emitter (SCE) with a raised emitter structure. The model calculated the electric field distribution, the electron emission characteristics, and the electron trajectories, which were useful for analyzing and understanding the microscopic mechanism of the electron emissions of the new SCE structure. It was found that the new structure increased the probability of electrons being collected by the anode which led to an increase of the anode current despite of the decrease of field emission current. This study benefits the advanced design of emitter structures in nanoscale technology for new types of electron sources. © 2016 IOP Publishing Ltd. (24 refs.)Main Heading: Electron emissionControlled terms: Anodes - Design - Electric fields - Electrodes - Electrons - NanotechnologyUncontrolled terms: Electric field distributions - Electron emission properties - Emission characteristics - Field emission currents - Finite integration technique - Nano-meter scale - Nanoscale technologies - Surface-conduction electron emittersClassification Code: 701.1 Electricity: Basic Concepts and PhenomenaElectricity: Basic Concepts and Phenomena - 714.1 Electron TubesElectron Tubes - 761 NanotechnologyNanotechnology
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Influence of absorption on stability of terahertz difference frequency generation
Huang, Nan1; Liu, Hongjun1; Sun, Qibing1; Wang, Zhaolu1; Li, Shaopeng1; Han, Jing1 Source: Applied Optics, v 55, n 3, p 444-448, January 20, 2016
; ISSN: 1559128X, E-ISSN: 21553165; DOI: 10.1364/AO.55.000444;
Publisher: OSA - The Optical SocietyAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, China
Abstract: This work presents numerical studies of the stability feature of terahertz difference frequency generation (THz-DFG) with a ZnGeP2crystal using two pump wavelengths. We found that the maximum output of a THz wave is located in the unstable output region because of the competitive equilibrium between the absorption and the gain. Furthermore, the output stability is dependent on the pump stability. Different from the results at the pump wavelength of 9.588 μm, there is neither an appropriate stable output region nor gain saturation region at the pump wavelength of 1.064 μm for a larger absorption coefficient. This work demonstrates that the stable output region of the THz wave is difficult to obtain when the pump absorption is excessively large in DFG. © 2016 Optical Society of America. (24 refs.)Main Heading: Terahertz wavesControlled terms: Optical frequency conversion - StabilityUncontrolled terms: Absorption co-efficient - Competitive equilibrium - Difference-frequency generation - Gain saturation - Maximum output - Output stability - Pump absorption - Pump wavelengthClassification Code: 711 Electromagnetic WavesElectromagnetic Waves - 741.1.1 Nonlinear OpticsNonlinear Optics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Yb-doped LMA fiber fabrication using chelate precursor doping technique
Wang, Zhen1, 2, 3; Gao, Cong1; Ni, Li1; Wang, Xiaolong1; Peng, Kun1, 2, 3; Wang, Yuying1; Zhan, Huan2, 3; Wang, Jianjun1; Jing, Feng1; Lin, Aoxiang1 Source: 2015 11th Conference on Lasers and Electro-Optics Pacific Rim, CLEO-PR 2015, v 1, January 7, 2016, 2015 11th Conference on Lasers and Electro-Optics Pacific Rim, CLEO-PR 2015; ISBN-13: 9781467371094; DOI: 10.1109/CLEOPR.2015.7375814; Article number: 7375814; Conference: 11th Conference on Lasers and Electro-Optics Pacific Rim, CLEO-PR 2015, August 24, 2015 - August 28, 2015;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 Research Center of Laser Fusion, China Academy of Engineering Physics, Mianyang, China2 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics (XIOPM), Chinese Academy of Sciences (CAS), Xi'an, China3 Graduate School of Chinese Academy of Sciences (CAS), Beijing, China
Abstract: We report on the fabrication of a kW-level Yb-doped fiber by using chelate precursor doping technique. Lasing performance was tested up to 1 kW laser output with slope efficiency of 81.8%. © 2015 IEEE. (8 refs.)Main Heading: ChelationControlled terms: YtterbiumUncontrolled terms: Chelate precursor - Doping techniques - Laser output - Lasing performance - Slope efficiencies - Yb-doped - Yb-doped fibersClassification Code: 547.2 Rare Earth MetalsRare Earth Metals - 802.2 Chemical ReactionsChemical Reactions
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Research of LD-pumped passively Q-switched Yb:YAG thin disk laser
Wang, Xu1, 2; Cheng, Guang-Hua1; Sun, Zhe1 Source: Guangzi Xuebao/Acta Photonica Sinica, v 45, n 3, March 1, 2016; Language: Chinese
; ISSN: 10044213; DOI: 10.3788/gzxb20164503.0314009; Article number: 0314009;
Publisher: Chinese Optical SocietyAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, China2 University of Chinese Academy of Sciences, Beijing, China
Abstract: Using 940 nm diode laser as pumping source, a passively Q-switched Yb:YAG thin disk laser by Cr4+:YAG was realized. The Yb:YAG disk with 500 μm thickness was employed, the Yb3+atom fraction is 10%. The distribution of temperature in Yb:YAG disk with direct water cooling and SiC cooling with different thickness was theoretically simulated, respectively. The maximum output power of 2.8 W at 1030 nm was obtained with 800 μm SiC cooling, the output power has increased by 40% than that obtained with direct water cooling. The initial transmission of Cr4+:YAG crystal and the output coupling rate were optimized by Degnan's theory. With the initial transmission of Cr4+:YAG crystal of 93% and the output coupling rate of 10%, a stable pulse train of 1.95 W averaged output power with a pulse energy of 1.2 mJ and pulse width of 74 ns were obtained with 800 μm SiC cooling. The repetition rate is 1.6 kHz, the slope efficiency is 18.1%, and the beam quality Mx2=1.622, My2=1.616. © 2016, Science Press. All right reserved. (17 refs.)Main Heading: Pumping (laser)Controlled terms: Cooling - Cooling water - Lasers - Q switched lasers - Q switching - Silicon carbide - Solid state lasers - YtterbiumUncontrolled terms: Different thickness - Direct water cooling - Distribution of temperature - Maximum output power - Output coupling - Passively Q-switched - Slope efficiencies - Thin-disk lasersClassification Code: 547.2 Rare Earth MetalsRare Earth Metals - 641.2 Heat TransferHeat Transfer - 744 LasersLasers - 804.2 Inorganic CompoundsInorganic Compounds
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Single-walled carbon nanotube saturable absorber for a diode-pumped passively mode-locked Nd,Y:SrF2laser
Li, Chun1; Cai, Wei1; Liu, Jie1; Su, Liangbi2; Jiang, Dapeng2; Ma, Fengkai2; Zhang, Qian2; Xu, Jun3; Wang, Yonggang4 Source: Optics Communications, v 372, p 76-79, August 1, 2016
; ISSN: 00304018; DOI: 10.1016/j.optcom.2016.04.012;
Publisher: ElsevierAuthor affiliation: 1 Shandong Provincial Key Laboratory of Optics and Photonic Device, School of Physics and Electronics, Shandong Normal University, Jinan, China2 Key Laboratory of Transparent and Opto-functional Inorganic Materials, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, China3 School of Physics Science and Engineering, Institute for Advanced Study, Tongji University, Shanghai, China4 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, China
Abstract: A reflective single-walled carbon nanotube as saturable absorber has been firstly adopted to a passively mode-locked Nd,Y:SrF2crystal. Without any dispersion compensation, the stably mode-locked laser delivers pulses with pulse width as short as 1.7 ps, repetition rate of 107.8 MHz and center wavelength of 1056 nm. The oscillator produces maximum average output power of 319 mW corresponding with a high slope efficiency of 20.2%. The single pulse energy and the peak power are 2.96 nJ and 1.74 kW, respectively. The experimental results show that single-walled carbon nanotube is an excellent saturable absorber for mode-locked lasers. © 2016 Published by Elsevier B.V. (27 refs.)Main Heading: Single-walled carbon nanotubes (SWCN)Controlled terms: Carbon nanotubes - Lasers - Mode-locked fiber lasers - Nanotubes - Passive mode locking - Pulse repetition rate - Q switched lasers - Saturable absorbers - YarnUncontrolled terms: Average output power - Center wavelength - Disordered crystals - High slope efficiency - Mode-locked laser - Passively mode-locked - Single pulse energy - Single-walled carbon nanotube saturable absorbersClassification Code: 744.1 Lasers, GeneralLasers, General - 761 NanotechnologyNanotechnology - 819.4 Fiber ProductsFiber Products
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Accelerating incoherent hollow beams beyond the paraxial regime
Yang, Yanlong1, 2; Yan, Shaohui1; Yu, Xianghua1; Li, Manman1, 2; Yao, Baoli1 Source: Optics Express, v 24, n 24, p 27683-27690, November 28, 2016; E-ISSN: 10944087; DOI: 10.1364/OE.24.027683;
Publisher: OSA - The Optical SocietyAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China2 University of Chinese Academy of Sciences, Beijing; 100049, China
Abstract: We propose a non-paraxial hollow accelerating beam, which is formed by incoherently superposing two well-designed coherent accelerating beams. Very interestingly, this incoherent superposition does not hamper the acceleration dynamics pertaining to the coherent ones, but results in a hollow intensity pattern in the cross section transverse to the circular accelerating trajectory. By a simple optimization, this hollow cross section pattern can be effectively extended to an angle close to 90°. The magnitude and the phase of the angular spectrum of the beam are given followed by a suggested scheme to generate the beam in practice. Such highly self-bending hollow beams may find applications in some fields such as optical manipulation. © 2016 Optical Society of America. (27 refs.)Main Heading: Spectrum analysisControlled terms: Optical constants - OpticsUncontrolled terms: Angular spectra - Hollow beams - Hollow cross-sections - Incoherent superposition - Intensity patterns - nocv1 - Optical manipulation - ParaxialClassification Code: 741.1 Light/OpticsLight/Optics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Non-negative matrix factorization with sinkhorn distance
Qian, Wei1; Hong, Bin1; Cai, Deng1; He, Xiaofei1; Li, Xuelong2 Source: IJCAI International Joint Conference on Artificial Intelligence, v 2016-January, p 1960-1966, 2016, Proceedings of the 25th International Joint Conference on Artificial Intelligence, IJCAI 2016
; ISSN: 10450823; Conference: 25th International Joint Conference on Artificial Intelligence, IJCAI 2016, July 9, 2016 - July 15, 2016; Sponsor: AI Journal; Arizona State University; Baidu; et al.; IBM Watson; Sony;
Publisher: International Joint Conferences on Artificial IntelligenceAuthor affiliation: 1 State Key Lab of CAD and CG, College of Computer Science, Zhejiang University, China2 Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, China
Abstract: Non-negative Matrix Factorization (NMF) has received considerable attentions in various areas for its psychological and physiological interpretation of naturally occurring data whose representation may be parts-based in the human brain. Despite its good practical performance, one shortcoming of original NMF is that it ignores intrinsic structure of data set. On one hand, samples might be on a manifold and thus one may hope that geometric information can be exploited to improve NMF's performance. On the other hand, features might correlate with each other, thus conventional L2distance can not well measure the distance between samples. Although some works have been proposed to solve these problems, rare connects them together. In this paper, we propose a novel method that exploits knowledge in both data manifold and features correlation. We adopt an approximation of Earth Mover's Distance (EMD) as metric and add a graph regularized term based on EMD to NMF. Furthermore, we propose an efficient multiplicative iteration algorithm to solve it. Our empirical study shows the encouraging results of the proposed algorithm comparing with other NMF methods. (25 refs.)Main Heading: Matrix algebraControlled terms: Artificial intelligence - Factorization - Iterative methodsUncontrolled terms: Data manifolds - Earth Mover's distance - Empirical studies - Geometric information - Intrinsic structures - Iteration algorithms - Naturally occurring - Nonnegative matrix factorizationClassification Code: 723.4 Artificial IntelligenceArtificial Intelligence - 921 MathematicsMathematics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Wavelength conversion of QPSK and 16-QAM coherent signals in a CMOS compatible spiral waveguide
Da Ros, Francesco1; da Silva, Edson Porto1; Zibar, Darko1; Chu, Sai T.2; Little, Brent E.3; Morandotti, Roberto4; Galili, Michael1; Moss, David J.5; Oxenløwe, Leif K.1 Source: Optics InfoBase Conference Papers, July 21, 2014, Integrated Photonics Research, Silicon and Nanophotonics, IPRSN 2016; ISBN-13: 9781943580149; Conference: Integrated Photonics Research, Silicon and Nanophotonics, IPRSN 2016, July 18, 2016 - July 20, 2016; Sponsor: AMERICAN ELEMENTS; NUFERN; OSA; Yenista Optics;
Publisher: OSA - The Optical SocietyAuthor affiliation: 1 DTU Fotonik, Technical University of Denmark, DTU, Kongens Lyngby; 2800, Denmark2 Department of Physics and Materials Science, City University of Hong Kong, Hong Kong3 Xi'an Institute of Optics and Precision Mechanics, CAS, Xi'an, China4 INSR - énergie, Matériaux et Télécommunications, 1650 Blvd Lionel Boulet, Varennes; QC; J3X1S2, Canada5 Centre for Microphotonics, Swinburne University of Technology, Hawthorn; VIC; 3122, Australia
Abstract: We characterize a wavelength converter based on a 50-cm long low-loss spiral Hydex waveguide. A 10-nm FWM bandwidth is shown over which low OSNR penalty (< 0.5dB) wavelength conversion of QPSK and 16-QAM is reported. © OSA 2016. (17 refs.)Main Heading: WaveguidesControlled terms: CMOS integrated circuits - Nanophotonics - PhotonicsUncontrolled terms: CMOS Compatible - Coherent signals - Low-loss - Spiral waveguides - Wavelength converterClassification Code: 714.2 Semiconductor Devices and Integrated CircuitsSemiconductor Devices and Integrated Circuits - 714.3 WaveguidesWaveguides - 741.1 Light/OpticsLight/Optics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Temporal Multimodal Learning in Audiovisual Speech Recognition
Hu, Di1; Li, Xuelong2; Lu, Xiaoqiang2 Source: Proceedings of the IEEE Computer Society Conference on Computer Vision and Pattern Recognition, v 2016-December, p 3574-3582, December 9, 2016, Proceedings - 29th IEEE Conference on Computer Vision and Pattern Recognition, CVPR 2016
; ISSN: 10636919; ISBN-13: 9781467388504; DOI: 10.1109/CVPR.2016.389; Article number: 7780758; Conference: 29th IEEE Conference on Computer Vision and Pattern Recognition, CVPR 2016, June 26, 2016 - July 1, 2016;
Publisher: IEEE Computer SocietyAuthor affiliation: 1 School of Computer Science and Center for OPTical IMagery Analysis and Learning (OPTIMAL), Northwestern Polytechnical University, Xi'an; 710072, China2 Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China
Abstract: In view of the advantages of deep networks in producing useful representation, the generated features of different modality data (such as image, audio) can be jointly learned using Multimodal Restricted Boltzmann Machines (MRB-M). Recently, audiovisual speech recognition based the M-RBM has attracted much attention, and the MRBM shows its effectiveness in learning the joint representation across audiovisual modalities. However, the built networks have weakness in modeling the multimodal sequence which is the natural property of speech signal. In this paper, we will introduce a novel temporal multimodal deep learning architecture, named as Recurrent Temporal Multimodal RB-M (RTMRBM), that models multimodal sequences by transforming the sequence of connected MRBMs into a probabilistic series model. Compared with existing multimodal networks, it's simple and efficient in learning temporal joint representation. We evaluate our model on audiovisual speech datasets, two public (AVLetters and AVLetters2) and one self-build. The experimental results demonstrate that our approach can obviously improve the accuracy of recognition compared with standard MRBM and the temporal model based on conditional RBM. In addition, RTMRBM still outperforms non-temporal multimodal deep networks in the presence of the weakness of long-term dependencies. © 2016 IEEE. (29 refs.)Main Heading: Speech recognitionControlled terms: Computer vision - Pattern recognitionUncontrolled terms: Audio visual speech recognition - Audio-visual speech - Long-term dependencies - Multi-modal learning - Multimodal network - Natural properties - Restricted boltzmann machine - Temporal modelingClassification Code: 723.5 Computer ApplicationsComputer Applications - 751.5 SpeechSpeech
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Learning spatio-temporal representations for action recognition: A genetic programming approach
Liu, Li1, 2; Shao, Ling1, 2; Li, Xuelong3; Lu, Ke4, 5 Source: IEEE Transactions on Cybernetics, v 46, n 1, p 158-170, January 2016
; ISSN: 21682267; DOI: 10.1109/TCYB.2015.2399172; Article number: 7042326;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 College of Electronic and Information Engineering, Nanjing University of Information Science and Technology, Nanjing, China2 Department of Computer Science and Digital Technologies, Northumbria University, Newcastle upon Tyne, United Kingdom3 Center for Optical Imagery Analysis and Learning, State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, China4 University of Chinese Academy of Sciences, Beijing, China5 Beijing Center for Mathematics and Information Interdisciplinary Sciences, Beijing, China
Abstract: Extracting discriminative and robust features from video sequences is the first and most critical step in human action recognition. In this paper, instead of using handcrafted features, we automatically learn spatio-temporal motion features for action recognition. This is achieved via an evolutionary method, i.e., genetic programming (GP), which evolves the motion feature descriptor on a population of primitive 3D operators (e.g., 3D-Gabor and wavelet). In this way, the scale and shift invariant features can be effectively extracted from both color and optical flow sequences. We intend to learn data adaptive descriptors for different datasets with multiple layers, which makes fully use of the knowledge to mimic the physical structure of the human visual cortex for action recognition and simultaneously reduce the GP searching space to effectively accelerate the convergence of optimal solutions. In our evolutionary architecture, the average cross-validation classification error, which is calculated by an support-vector-machine classifier on the training set, is adopted as the evaluation criterion for the GP fitness function. After the entire evolution procedure finishes, the best-so-far solution selected by GP is regarded as the (near-)optimal action descriptor obtained. The GP-evolving feature extraction method is evaluated on four popular action datasets, namely KTH, HMDB51, UCF YouTube, and Hollywood2. Experimental results show that our method significantly outperforms other types of features, either hand-designed or machine-learned. © 2015 IEEE. (63 refs.)Main Heading: Genetic programmingControlled terms: Adaptive optics - Classification (of information) - Feature extraction - Genetic algorithms - Gesture recognition - Motion estimationUncontrolled terms: Classification errors - Evolutionary architectures - Evolutionary method - Feature extraction methods - Human visual cortex - Human-action recognition - Physical structures - Support vector machine classifiers
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Large-Scale Aerial Image Categorization Using a Multitask Topological Codebook
Zhang, Luming1; Wang, Meng1; Hong, Richang1; Yin, Bao-Cai2; Li, Xuelong3 Source: IEEE Transactions on Cybernetics, v 46, n 2, p 535-545, February 2016
; ISSN: 21682267; DOI: 10.1109/TCYB.2015.2408592; Article number: 7061407;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 Computer Science and Information Engineering Department, Hefei University of Technology, Hefei, China2 School of Transportation, Beijing University of Technology, Beijing, China3 Center for Optical Imagery Analysis and Learning, State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Xi'an, China
Abstract: Fast and accurately categorizing the millions of aerial images on Google Maps is a useful technique in pattern recognition. Existing methods cannot handle this task successfully due to two reasons: 1) the aerial images' topologies are the key feature to distinguish their categories, but they cannot be effectively encoded by a conventional visual codebook and 2) it is challenging to build a realtime image categorization system, as some geo-Aware Apps update over 20 aerial images per second. To solve these problems, we propose an efficient aerial image categorization algorithm. It focuses on learning a discriminative topological codebook of aerial images under a multitask learning framework. The pipeline can be summarized as follows. We first construct a region adjacency graph (RAG) that describes the topology of each aerial image. Naturally, aerial image categorization can be formulated as RAG-To-RAG matching. According to graph theory, RAG-To-RAG matching is conducted by enumeratively comparing all their respective graphlets (i.e., small subgraphs). To alleviate the high time consumption, we propose to learn a codebook containing topologies jointly discriminative to multiple categories. The learned topological codebook guides the extraction of the discriminative graphlets. Finally, these graphlets are integrated into an AdaBoost model for predicting aerial image categories. Experimental results show that our approach is competitive to several existing recognition models. Furthermore, over 24 aerial images are processed per second, demonstrating that our approach is ready for real-world applications. © 2013 IEEE. (58 refs.)Main Heading: TopologyControlled terms: Adaptive boosting - Graph theory - Image matching - Image segmentation - Imaging systems - Pattern recognitionUncontrolled terms: AdaBoost model - Aerial images - Multitask learning - Real-time images - Recognition models - Region adjacency graphs - Time consumption - Visual codebook
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


The R&D of the 20 in. MCP-PMTs for JUNO
Chang, Yaping1, 2, 3; Huang, Guorui4; Heng, Yuekun1, 2; Li, Dong4; Liu, Huilin5; Liu, Shulin1, 2; Li, Weihua5; Ning, Zhe1, 2; Qi, Ming6; Qian, Sen1, 2; Sun, Jianning4; Si, Shuguang4; Tian, Jinshou5; Wang, Xingchao4; Wang, Xing5; Wang, Yifang1, 2; Wei, Yonglin5; Wang, Wenwen6; Xia, Jingkai1, 2, 3; Xin, Liwei5; Zhao, Tianchi1 Source: Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, v 824, p 143-144, July 11, 2016
; ISSN: 01689002; DOI: 10.1016/j.nima.2015.10.106;
Publisher: ElsevierAuthor affiliation: 1 Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, China2 State Key Laboratory of Particle Detection and Electronics, Beijing, China3 University of Chinese Academy of Sciences, Beijing, China4 North Night Vision Tech. Ltd., Nanjing, China5 Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, China6 Department of Physics, Nanjing University, Nanjing, China
Abstract: A new concept of large area photomultiplier based on MCPs was conceived for JUNO by the scientists in IHEP, and with the collaborative work of the MCP-PMT collaboration in China, 8 in. and 20 in. prototypes were produced. Test results show that this type of MCP-PMT can have good SPE performance as the traditional dynode type PMTs. © 2015 Elsevier B.V. (3 refs.)Main Heading: Nuclear instrumentationUncontrolled terms: Collaborative Work - High QE - Large area - MCP - MCP-PMT - PMT
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Image Categorization by Learning a Propagated Graphlet Path
Zhang, Luming1; Hong, Richang1; Gao, Yue2; Ji, Rongrong3; Dai, Qionghai2; Li, Xuelong4 Source: IEEE Transactions on Neural Networks and Learning Systems, v 27, n 3, p 674-685, March 2016
; ISSN: 2162237X, E-ISSN: 21622388; DOI: 10.1109/TNNLS.2015.2444417; Article number: 7335617;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 Department of Electrical Engineering and Information System, Hefei University of Technology, Hefei, China2 Tsinghua University, Beijing, China3 Department of Cognitive Science, School of Information Science and Engineering, Xiamen University, Xiamen, China4 Center for OPTical IMagery Analysis and Learning, State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, China
Abstract: Spatial pyramid matching is a standard architecture for categorical image retrieval. However, its performance is largely limited by the prespecified rectangular spatial regions when pooling local descriptors. In this paper, we propose to learn object-shaped and directional receptive fields for image categorization. In particular, different objects in an image are seamlessly constructed by superpixels, while the direction captures human gaze shifting path. By generating a number of superpixels in each image, we construct graphlets to describe different objects. They function as the object-shaped receptive fields for image comparison. Due to the huge number of graphlets in an image, a saliency-guided graphlet selection algorithm is proposed. A manifold embedding algorithm encodes graphlets with the semantics of training image tags. Then, we derive a manifold propagation to calculate the postembedding graphlets by leveraging visual saliency maps. The sequentially propagated graphlets constitute a path that mimics human gaze shifting. Finally, we use the learned graphlet path as receptive fields for local image descriptor pooling. The local descriptors from similar receptive fields of pairwise images more significantly contribute to the final image kernel. Thorough experiments demonstrate the advantage of our approach. © 2012 IEEE. (52 refs.)Main Heading: Image matchingControlled terms: Image retrieval - Imaging systems - Pixels - SemanticsUncontrolled terms: Embedding algorithms - Image Categorization - Image comparison - Local descriptors - Local image descriptors - Selection algorithm - Spatial Pyramid Matching - Standard architecture
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Speed up deep neural network based pedestrian detection by sharing features across multi-scale models
Jiang, Xiaoheng1; Pang, Yanwei1; Li, Xuelong2; Pan, Jing1, 3 Source: Neurocomputing, v 185, p 163-170, April 12, 2016
; ISSN: 09252312, E-ISSN: 18728286; DOI: 10.1016/j.neucom.2015.12.042;
Publisher: ElsevierAuthor affiliation: 1 School of Electronic Information Engineering, Tianjin University, Tianjin, China2 Center for OPTical IMagery Analysis and Learning (OPTIMAL), State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, Shaanxi, China3 School of Electronic Engineering, Tianjin University of Technology and Education, Tianjin, China
Abstract: Deep neural networks (DNNs) have now demonstrated state-of-the-art detection performance on pedestrian datasets. However, because of their high computational complexity, detection efficiency is still a frustrating problem even with the help of Graphics Processing Units (GPUs). To improve detection efficiency, this paper proposes to share features across a group of DNNs that correspond to pedestrian models of different sizes. By sharing features, the computational burden for extracting features from an image pyramid can be significantly reduced. Simultaneously, we can detect pedestrians of several different scales on one single layer of an image pyramid. Furthermore, the improvement of detection efficiency is achieved with negligible loss of detection accuracy. Experimental results demonstrate the robustness and efficiency of the proposed algorithm. © 2015 The Authors. (35 refs.)Main Heading: Feature extractionControlled terms: Complex networks - Computational efficiency - Computer graphics - Efficiency - Neural networks - Object detection - Program processorsUncontrolled terms: Computational burden - Convolutional neural network - Deep neural networks - Detection efficiency - Detection performance - Graphics processing units - Pedestrian detection - Share features
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Passively mode-locked erbium-doped fiber laser via a D-shape-fiber-based MoS2saturable absorber with a very low nonsaturable loss
Duan, Li-Na1; Su, Yu-Long1; Wang, Yong-Gang1; Li, Lu1; Wang, Xi1; Wang, Yi-Shan1 Source: Chinese Physics B, v 25, n 2, January 10, 2016
; ISSN: 16741056; DOI: 10.1088/1674-1056/25/2/024206; Article number: 024206;
Publisher: Institute of Physics PublishingAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, China
Abstract: We report on the generation of conventional and dissipative solitons in erbium-doped fiber lasers by the evanescent field interaction between the propagating light and a multilayer molybdenum disulfide (MoS2) thin film. The MoS2film is fabricated by depositing the MoS2water-ethanol mixture on a D-shape-fiber (DF) repetitively. The measured nonsaturable loss, saturable optical intensity, and the modulation depth of this device are 13.3%, 110 MW/cm2, and 3.4% respectively. Owing to the very low nonsaturable loss, the laser threshold of conventional soliton is as low as 4.8 mW. The further increase of net cavity dispersion to normal regime, stable dissipation soliton pulse trains with a spectral bandwidth of 11.7 nm and pulse duration of 116 ps are successfully generated. Our experiment demonstrates that the MoS2-DF device can indeed be used as a high performance saturable absorber for further applications in ultrafast photonics. © 2016 Chinese Physical Society and IOP Publishing Ltd. (23 refs.)Main Heading: Mode-locked fiber lasersControlled terms: Erbium - Evanescent fields - Fiber lasers - Fibers - Film preparation - Laser mode locking - Molybdenum compounds - Nanosheets - Passive mode locking - Ring lasers - Saturable absorbers - SolitonsUncontrolled terms: Dissipative solitons - Erbium doped fiber laser - Molybdenum disulfide - Optical intensities - Passively mode-locked - Spectral bandwidth - Ultra-fast photonics - Water ethanol mixturesClassification Code: 547.2 Rare Earth MetalsRare Earth Metals - 701 Electricity and MagnetismElectricity and Magnetism - 744 LasersLasers - 761 NanotechnologyNanotechnology - 933 Solid State PhysicsSolid State Physics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Influence of atmospheric turbulence on detecting performance of all-day star sensor
Pan, Yue1, 2; Wang, Hu1; Shen, Yang1, 2; Xue, Yaoke1; Liu, Jie1 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 9903, 2016, Seventh International Symposium on Precision Mechanical Measurements
; ISSN: 0277786X, E-ISSN: 1996756X; ISBN-13: 9781510601673; DOI: 10.1117/12.2211689; Article number: 990318; Conference: 7th International Symposium on Precision Mechanical Measurements, ISPMM 2015, August 8, 2015 - August 12, 2015; Sponsor: China Instrument and Control Society; International Committee on Measurements and Instrumentation; National Natural Science Foundation of China;
Publisher: SPIEAuthor affiliation: 1 Xi'An Institute of Optics and Precision Mechanics of CAS, Xi'an, China2 University of Chinese Academy of Sciences, Beijing, China
Abstract: All-day star sensor makes it possible to observe stars in all-day time in the atmosphere. But the detecting performance is influenced by atmospheric turbulence. According to the characteristic of turbulence in long-exposure model, the modulation transfer function, point spread function and encircled power of the imaging system have been analyzed. Combined with typical star sensor optical system, the signal to noise ratio and the detectable stellar magnitude limit affected by turbulence have been calculated. The result shows the ratio of aperture diameter to atmospheric coherence length is main basis for the evaluation of the impact of turbulence. In condition of medium turbulence in day time, signal to noise ratio of the star sensor with diameter 120mm will drop about 4dB at most in typical work environment, and the detectable stellar limit will drop 1 magnitude. © 2016 SPIE. (10 refs.)Main Heading: Atmospheric turbulenceControlled terms: Atmospheric thermodynamics - Drops - Mechanical variables measurement - Optical systems - Optical transfer function - Signal detection - Signal to noise ratio - StarsUncontrolled terms: All-day - Aperture diameter - Atmospheric coherence length - Long exposures - Star sensors - Work environmentsClassification Code: 443.1 Atmospheric PropertiesAtmospheric Properties - 657.2 Extraterrestrial Physics and Stellar PhenomenaExtraterrestrial Physics and Stellar Phenomena - 716.1 Information Theory and Signal ProcessingInformation Theory and Signal Processing - 741.1 Light/OpticsLight/Optics - 741.3 Optical Devices and SystemsOptical Devices and Systems - 943.2 Mechanical Variables MeasurementsMechanical Variables Measurements
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Analysis of defocus in space based space optical debris detection
Zeng, De-Xian1; Hu, Bing-Liang2; Song, Hai-Jun2 Source: Guangzi Xuebao/Acta Photonica Sinica, v 45, n 1, January 1, 2016; Language: Chinese
; ISSN: 10044213; DOI: 10.3788/gzxb20164501.0111002; Article number: 0111002;
Publisher: Chinese Optical SocietyAuthor affiliation: 1 Equipment Academy, Beijing, China2 Key Laboratory of Spectral Imaging, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, China
Abstract: The reasons of the generation of defocus were discussed and the defocus change was analysed from the relative distance, atmospheric pressure and temperature change. The modulation transfer function model was proposed to study the image quality influenced by defocus. Then different defocus value leading image blurry was simulated. The simulation results indicate that the positive and negative defocus value induced by the relative distance, atmospheric pressure and temperature change can be counteracted. This paper provides an effective data to spatial camera design, compensating measure establishment and performance evaluation. © 2016, Science Press. All right reserved. (14 refs.)Main Heading: Space debrisControlled terms: Atmospheric pressure - Image quality - Modulation - Optical transfer function - Transfer functionsUncontrolled terms: Defocus - Modulation transfer - Optical detection - Pressure and temperature - Relative distances - Space environment - Space-based - Spatial cameraClassification Code: 443.1 Atmospheric PropertiesAtmospheric Properties - 656.1 Space FlightSpace Flight - 741.1 Light/OpticsLight/Optics - 921 MathematicsMathematics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Theoretical analysis of the electromagnetic field inside an anomalous-dispersion microresonator under synthetical pump
Xu, Xin1, 2; Hu, Xiaohong1, 2; Feng, Ye1, 2; Liu, Yuanshan1; Zhang, Wei1; Yang, Zhi1; Zhao, Wei1; Wang, Yishan1 Source: Chinese Physics B, v 25, n 3, January 18, 2016
; ISSN: 16741056; DOI: 10.1088/1674-1056/25/3/034208; Article number: 034208;
Publisher: Institute of Physics PublishingAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, China2 University of Chinese, Academy of Sciences, Beijing, China
Abstract: We study the spatiotemporal evolution of the electromagnetic field inside a microresonator showing an anomalous dispersion at the pump wavelength by using the normalized Lugiato-Lefever equation. Unlike the traditional single continuous wave (CW) pumping, an additional pump source consisting of periodical pulse train with variable repetition rate is adopted. The influences of the microresonator properties and the pump parameters on the field evolution and the electromagnetic field profile are analyzed. The simulation results indicate that, in the anomalous dispersion regime, both increases of the input pulse amplitude and the repetition frequency can result in the field profiles consisting of multiple peaks. A series of equidistant pulses can also be obtained by increasing the CW pump power. In addition, we find that a large physical detuning between the pump laser carrier and the cavity resonance frequency also causes the splitting of the inside field. © 2016 Chinese Physical Society and IOP Publishing Ltd. (37 refs.)Main Heading: Optical pumpingControlled terms: Dispersion (waves) - Electromagnetic fields - Microcavities - Nonlinear equations - Nonlinear optics - Pulse repetition rate - Pumping (laser) - Q switched lasers - ResonatorsUncontrolled terms: Anomalous dispersion - Cavity resonance frequency - Continuous waves - Field evolution - Lugiato-Lefever equation - Micro resonators - Repetition frequency - Spatiotemporal evolutionClassification Code: 701 Electricity and MagnetismElectricity and Magnetism - 714 Electronic Components and TubesElectronic Components and Tubes - 741.1.1 Nonlinear OpticsNonlinear Optics - 744.1 Lasers, GeneralLasers, General
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Growth of SiC nanowires by low pressure chemical vapor infiltration using different catalysts
Men, Jing1; Liu, Yongsheng1; Luo, Rong1, 2; Li, Weinan2; Cheng, Laifei1; Zhang, Litong1 Source: Journal of the European Ceramic Society, v 36, n 15, p 3615-3625, November 1, 2016
; ISSN: 09552219, E-ISSN: 1873619X; DOI: 10.1016/j.jeurceramsoc.2016.04.004;
Publisher: Elsevier LtdAuthor affiliation: 1 Science and Technology on Thermostructure Composite Materials Laboratory, Northwestern Polytechnical University, Xi'an; Shaanxi; 710072, China2 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; Shaanxi; 710119, China
Abstract: SiC nanowires were synthesized by LPCVI using different catalysts, and the influences of input gas ratio (α) and catalysts were investigated. The average diameter firstly decreased and then increased with increasing α. Under Ni-based catalysis, SiC nanowires were long and thin, and increased with increasing concentration; under Fe-based catalysis, they were short and thick, and the influence of concentration could be neglected. The growth of SiC nanowires was controlled by vapor-liquid-solid (VLS) growth mechanism and the liquid-solid interface between nanowire and metal droplet was the growth plane. At same concentration, the diameter grown under Ni-based catalyst decreased with decreasing diameter of catalyst droplet, while under Fe-based catalyst, the diameters were not affected by catalyst droplet because of the high concentration. SiC nanowires were synthesized in 2D C/SiC composites and could enhance the mechanical properties effectively because of energy consuming from the fracture, pulled up and debond of SiC nanowires. © 2016 Elsevier Ltd (45 refs.)Main Heading: Phase interfacesControlled terms: Catalysis - Catalysts - Drops - Fracture - Liquids - Nanowires - Nickel - Silicon carbideUncontrolled terms: 2D C/SiC composites - Fe-based catalysts - Liquid-solid interfaces - Low pressure chemical vapor infiltration - Ni-based catalyst - SiC nanowire - Vapor liquid solids - Vapor-liquid-solid growth mechanism
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Polarization imaging based on compressed sensing theory
Wang, Peng1, 2; Rong, Zhibin3; He, Junhua1; Lv, Pei1 Source: Hongwai yu Jiguang Gongcheng/Infrared and Laser Engineering, v 45, n 2, February 25, 2016; Language: Chinese
; ISSN: 10072276; DOI: 10.3788/IRLA201645.0228005; Article number: 0228005;
Publisher: Chinese Society of AstronauticsAuthor affiliation: 1 Xi'an Institute of Optics and Precision Mechanics of CAS, Xi'an, China2 University of Chinese Academic of Sciences, Beijing, China3 The Chinese People's Liberation Army 91550 Troops, Dalian, China
Abstract: Polarization imaging technology is a method that acquires the object images by collecting the polarization information of the target radiation or reflected signals. In particular, compared with the light intensity detection, it has unique advantages in the artificial target detection and surface recognition. Due to the short range and low quality of the conventional polarization imaging in complex imaging environment, a new kind of polarization imaging technology based on compressed sensing was proposed. The basic principle of compressed sensing theory was elaborated. By constructing reasonable sampling matrix and reconstruction algorithm, the specific imaging system was designed. Besides, the feasibility of this technology was confirmed through the imaging experiment. The study results in the air show the system can reconstruct the polarization images of the pre-positioned target. Additionally, in the existing experimental conditions, some measures are investigated and proposed to improve the system imaging performance. © 2016, Editorial Board of Journal of Infrared and Laser Engineering. All right reserved. (17 refs.)Main Heading: Image reconstructionControlled terms: Compressed sensing - Image processing - Imaging systems - Imaging techniques - Polarization - Signal reconstructionUncontrolled terms: Artificial targets - Experimental conditions - Imaging experiments - Imaging performance - Light intensity detection - Polarization images - Polarization imaging - Reconstruction algorithmsClassification Code: 716.1 Information Theory and Signal ProcessingInformation Theory and Signal Processing - 746 Imaging TechniquesImaging Techniques
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Hardware epoch superposition of X-ray pulsar-based navigation
Wu, Yaping1, 2; Zhao, Jianjun1; Wu, Guangmin1; Gao, Xiafang1, 2; Tang, Haifeng1, 2 Source: Hangkong Xuebao/Acta Aeronautica et Astronautica Sinica, v 37, n 2, p 662-668, February 25, 2016; Language: Chinese
; ISSN: 10006893; DOI: 10.7527/S1000-6893.2015.0164;
Publisher: AAAS Press of Chinese Society of Aeronautics and AstronauticsAuthor affiliation: 1 Faculty of Science, Kunming University of Science and Technology, Kunming, China2 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, China
Abstract: Based on the X-rays pulsar-based source simulation produced by the ground experimental system, using the method of hardware epoch superposition, the pulse profile is obtained fast and stable. The algorithm of epoch superposition and data integration implemented by the field programmable gate arrays (FPGA) has been studied that is firstly achieved by using MATLAB then converted to hardware description language (HDL) by MATLAB HDL Coder. Secondly, the stream file of Bit can be obtained, configuring the hardware by the compiler. Finally, the hardware module can be practicable in the FPGA. The arrived time data of photons obtained by MATLAB algorithm has some errors with the data obtained after the treatment of the hardware modules; the maximum error is two photon numbers in the single time window, and the average error value accounts for 0.084 % of the average statistic value; the different data accounts for 9.481% of the total number of data in the two sets of statistical pulse profile data. Such errors do not affect the navigation of the subsequent navigation module. The hardware implementation and data integration epoch superposition modules get high processing speed, compact device and low power consumption, which provides viable data processing hardware technical support for spacecraft navigation using X-ray pulsars. © 2016, Press of Chinese Journal of Aeronautics. All right reserved. (20 refs.)Main Heading: Computer hardware description languagesControlled terms: Data handling - Data integration - Errors - Field programmable gate arrays (FPGA) - Hardware - Logic gates - MATLAB - Navigation - Photons - Pulsars - Reconfigurable hardwareUncontrolled terms: Experimental system - Hardware design - Hardware implementations - Low-power consumption - Processing hardware - Signal source - Spacecraft navigation - Technical supportClassification Code: 605 Small Tools and HardwareSmall Tools and Hardware - 657.2 Extraterrestrial Physics and Stellar PhenomenaExtraterrestrial Physics and Stellar Phenomena - 721.2 Logic ElementsLogic Elements - 721.3 Computer CircuitsComputer Circuits - 723.1.1 Computer Programming LanguagesComputer Programming Languages - 723.2 Data Processing and Image ProcessingData Processing and Image Processing - 921 MathematicsMathematics - 931.3 Atomic and Molecular PhysicsAtomic and Molecular Physics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Thermal management technology of a liquid cooling thin-disk oscillator
Yang, Peng1; Ma, Lun1; Jiang, Yan-Ling1; Li, Wei1; Nie, Rong-Zhi2; Zhao, Peng-Fei2; She, Jiang-Bo2 Source: Guangzi Xuebao/Acta Photonica Sinica, v 45, n 3, March 1, 2016; Language: Chinese
; ISSN: 10044213; DOI: 10.3788/gzxb20164503.0314007; Article number: 0314007;
Publisher: Chinese Optical SocietyAuthor affiliation: 1 School of Information Engineering Chang an University, Xi'an; 710064, China2 State Key Laboratory of Transient Optics and Technology, Xi'an Institute of Optics and Precision Mechanics of CAS, Xi'an; 710119, China
Abstract: In order to solve the problem of the thermal effect of the laser gain media, a configuration named “immersed thin-disk oscillator” solid laser cooled directly with flow was proposed. Under the repeated pumping frequency of 10 Hz, a maximum output energy of 615mJ was realized. The optical-optical efficiency and the slope efficiency is 23% and 21% respectively. Based on the principle of fluid mechanics and thermodynamics, the thermal-flow-solid coupling model of lasing region was established. By using the software and the method of finite element analysis, the distribution characteristics of temperature field and velocity field were studied under the conditions of different flow rate and pump power. The wavefront aberration of the laser passing the gain region was simulated under the condition of liquid-cooled. The maximum optical path difference of the gain medium and coolant liquid are 0.7666λ and -4.7331λ respectively. The results show that the laser has a good thermal management performance. © 2016, Science Press. All right reserved. (13 refs.)Main Heading: Finite element methodControlled terms: Aberrations - Fluid mechanics - Laser cooling - Liquid lasers - Liquids - Solid state lasers - Temperature control - Thermal effects - Thermal variables control - Thermodynamics - Velocity - WavefrontsUncontrolled terms: Distribution characteristics - Liquid cooling - Management technologies - Method of finite elements - Optical path difference - Optical-optical efficiency - Thin-disk lasers - Wavefront aberrationsClassification Code: 641 Heat and Mass Transfer; ThermodynamicsHeat and Mass Transfer; Thermodynamics - 641.1 ThermodynamicsThermodynamics - 731.3 Specific Variables ControlSpecific Variables Control - 744 LasersLasers - 921.6 Numerical MethodsNumerical Methods - 931.1 MechanicsMechanics - 931.3 Atomic and Molecular PhysicsAtomic and Molecular Physics - 951 Materials ScienceMaterials Science
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Dual-wavelength synchronous mode-locked Yb:LSO laser using a double-walled carbon nanotube saturable absorber
Feng, Chao1; Hou, Wei1; Yang, Jimin1; Liu, Jie1; Zheng, Lihe2; Su, Liangbi2; Xu, Jun3; Wang, Yonggang4 Source: Applied Optics, v 55, n 13, p 3639-3644, May 1, 2016
; ISSN: 1559128X, E-ISSN: 21553165; DOI: 10.1364/AO.55.003639;
Publisher: OSA - The Optical SocietyAuthor affiliation: 1 Shandong Provincial Key Laboratory of Optics and Photonic Device, School of Physics and Electronics, Shandong Normal University, Jinan; 250014, China2 Key Laboratory of Transparent and Opto-Functional Advanced Inorganic Materials, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai; 201800, China3 School of Physics Science and Engineering, Institute for Advanced Study, Tongji University, Shanghai; 200092, China4 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China
Abstract: A dual-wavelength, passively mode-locked Yb:LSO laser was demonstrated using a double-walled carbon nanotube as a saturable absorber. The maximum average output power of the laser was 1.34 W at the incident pump power of 9.94 W. The two central wavelengths were 1057 and 1058 nm. The corresponding pulse duration of the autocorrelation interference pattern was about 15 ps, while the beat pulse repetition rate was 0.17 THz and the width of one beat pulse about 2 ps. When the incident pump power was above 10.25 W, a multiwavelength mode-locked oscillation phenomenon was observed. After employing a pair of SF10 prisms, a 1058.7 nm singlewavelength mode-locked laser was obtained with a pulse width of 7 ps. © 2016 Optical Society of America. (24 refs.)Main Heading: Multiwalled carbon nanotubes (MWCN)Controlled terms: Carbon nanotubes - Mode-locked fiber lasers - Nanotubes - Passive mode locking - Pulse repetition rate - Pumping (laser) - Saturable absorbers - Yarn - YtterbiumUncontrolled terms: Autocorrelation interference - Average output power - Central wavelength - Double walled carbon nanotubes - Incident pump power - Oscillation phenomenon - Passively mode-locked - Single wavelengthClassification Code: 547.2 Rare Earth MetalsRare Earth Metals - 744.1 Lasers, GeneralLasers, General - 761 NanotechnologyNanotechnology - 819.4 Fiber ProductsFiber Products
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


A new spectral-spatial algorithm method for hyperspectral image target detection
Wang, Cai-Ling1, 2; Wang, Hong-Wei3; Hu, Bing-Liang1; Wen, Jia4; Xu, Jun5; Li, Xiang-Juan2 Source: Guang Pu Xue Yu Guang Pu Fen Xi/Spectroscopy and Spectral Analysis, v 36, n 4, p 1163-1169, April 1, 2016; Language: Chinese
; ISSN: 10000593; DOI: 10.3964/j.issn.1000-0593(2016)04-1163-07;
Publisher: Science PressAuthor affiliation: 1 Xi'an Institute of Optics and Precision Mechanics of Chinese Academy of Sciences, Key Lab of Spectral Imaging, Xi'an; 710119, China2 Xi'an Shiyou University, School of Computer Science, Xi'an; 710065, China3 Engineering University of the Chinese People's Armed Police Force, Xi'an; 710086, China4 Institute of Software of Chinese Academy of Sciences, Beijing; 100080, China5 School of Information Engineering, East China Jiaotong Univeristy, Nanchang; 330013, China
Abstract: With high-resolution spatial information and continuous spectrum information, hyperspectral remote sensing image -has a unique advantage in the field of target detection. Traditional hyperspectral remote sensing image target detection methods emphasis on using spectral information to determine deterministic algorithm and statistical algorithms. Deterministic algorithms find the target by calculating the distance between the target spectrum and detected spectrum however, they are unable to detect sub-pixel target and are easily affected by noise. Statistical methods which calculate background statistical characteristics to detect abnormal point as target. It can detect subpixel target targets and small targets better thanbig size target,. With the spatial resolution increasing, subpixel target detection target has gradually grown to a single pixel and multi-pixel target. At this point, hyperspectral image usually has large homogeneous regions where the neighboring pixels wihin the regions consist of the same type of materials and have a similar spectral characteristics, therefore, the spatial information should be needed to incorporate into the algorithm for targe detection. This paper proposes an algorithm for hyperspectral target detection combined spectrum characteristics and spatial characteristics. The algorithm is based on traditional target detection operator and combined neighborhood clustering statistics. Firstly, the algorithm uses target detection operator to divided hyperspectral image into a potential target region and background region. Then, it calculates the centroid of the potential target area. Finally, as the centroid for neighborhood clustering center to clust data in order to exclud background from potential target area, through iterative calculation to obtain the final results of the target detection. The traditional statistics algorithms defines the total image as background area in order to extract background statistics features, and the algorithm propsed devided the total image into background part and potential target part, which cut off the target interference for background statistics feature extraction. Compared with CEM operators and ACE operators, the algorithm proposed outperforms than traditional operators in big target detection. © 2016, Peking University Press. All right reserved. (12 refs.)Main Heading: Radar target recognitionControlled terms: Algorithms - Clustering algorithms - Feature extraction - Image processing - Image reconstruction - Iterative methods - Pixels - Remote sensing - Spectroscopy - Statistics - Target trackingUncontrolled terms: Hyperspectral image processing - Hyperspectral Remote Sensing Image - Hyperspectral target detection - Neighborhood clustering - Spectral algorithm - Statistical characteristics - Statistical operators - Subpixel target detectionClassification Code: 716.2 Radar Systems and EquipmentRadar Systems and Equipment - 903.1 Information Sources and AnalysisInformation Sources and Analysis - 921.6 Numerical MethodsNumerical Methods - 922.2 Mathematical StatisticsMathematical Statistics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Systematic experimental study on a highly efficient terahertz source based on two-color laser-induced air plasma
Xie, Jun1, 2; Fan, Wen-Hui1; Chen, Xu1, 2 Source: Laser Physics, v 26, n 5, May 2016
; ISSN: 1054660X, E-ISSN: 15556611; DOI: 10.1088/1054-660X/26/5/055002; Article number: 055002;
Publisher: Institute of Physics PublishingAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, China2 University of Chinese Academy of Sciences, Beijing, China
Abstract: In this paper, highly efficient terahertz radiation generated by two-color femtosecond laser-induced air plasma is reported. A number of variables that can obviously influence terahertz generation and detection have been investigated systematically. The dependence on experimental parameters, including pulse energy, the rotation angle of beta-barium boron oxide (BBO) crystal, the distance between BBO crystal and laser-induced plasma, focal length, chopper frequency, and detection angle are presented, and the optimal values of these parameters have also been obtained experimentally. Finally, a highly efficient terahertz source has been achieved and can be utilized to carry out further investigation on terahertz sensing, spectroscopy, and imaging. © 2016 Astro Ltd. (20 refs.)Main Heading: Plasma diagnosticsControlled terms: Laser produced plasmas - Terahertz spectroscopy - Terahertz wavesUncontrolled terms: Air plasmas - Experimental parameters - highly efficient - Laser induced - Laser induced plasma - Tera Hertz - Terahertz generation - Terahertz radiationClassification Code: 711 Electromagnetic WavesElectromagnetic Waves - 931.1 MechanicsMechanics - 932.3 Plasma PhysicsPlasma Physics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Multifrequency sources of quantum correlated photon Pairs on-chip: A path toward integrated Quantum Frequency Combs
Caspani, Lucia1, 2; Reimer, Christian1; Kues, Michael1; Roztocki, Piotr1; Clerici, Matteo1, 4; Wetzel, Benjamin1, 5; Jestin, Yoann1; Ferrera, Marcello1, 2; Peccianti, Marco2, 4; Pasquazi, Alessia2, 4; Razzari, Luca1; Little, Brent E.6; Chu, Sai T.7; Moss, David J.8; Morandotti, Roberto1, 3 Source: Nanophotonics, v 5, n 2, p 351-362, June 1, 2016; E-ISSN: 21928614; DOI: 10.1515/nanoph-2016-0029;
Publisher: Walter de Gruyter GmbHAuthor affiliation: 1 Institut National de la Recherche Scientifique - Energie Materiaux et Telecommunications, Université du Québec, 1650 Boulevard Lionel-Boulet, Varennes; QC; J3X 1S2, Canada2 Institute of Photonics and Quantum Sciences, Heriot-Watt University, Edinburgh; EH14 4AS, United Kingdom3 Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu; 610054, China4 School of Engineering, University of Glasgow, UK, United Kingdom5 Department of Physics and Astronomy, University of Sussex, Falmer, United Kingdom6 State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Science, China7 Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Hong Kong, Hong Kong8 Centre for Microphotonics, Swinburne University of Technology, Hawthorn; VIC, Australia
Abstract: Recent developments in quantum photonics have initiated the process of bringing photonic-quantumbased systems out-of-the-lab and into real-world applications. As an example, devices to enable the exchange of a cryptographic key secured by the laws of quantum mechanics are already commercially available. In order to further boost this process, the next step is to transfer the results achieved by means of bulky and expensive setups into miniaturized and affordable devices. Integrated quantum photonics is exactly addressing this issue. In this paper, we briefly review the most recent advancements in the generation of quantum states of light on-chip. In particular, we focus on optical microcavities, as they can offer a solution to the problem of low efficiency that is characteristic of the materials typically used in integrated platforms. In addition, we show that specifically designed microcavities can also offer further advantages, such as compatibility with telecom standards (for exploiting existing fibre networks) and quantum memories (necessary to extend the communication distance), as well as giving a longitudinal multimode character for larger information transfer and processing. This last property (i.e., the increased dimensionality of the photon quantum state) is achieved through the ability to generate multiple photon pairs on a frequency comb, corresponding to the microcavity resonances. Further achievements include the possibility of fully exploiting the polarization degree of freedom, even for integrated devices. These results pave the way for the generation of integrated quantum frequency combs that, in turn, may find important applications toward the realization of a compact quantum-computing platform. © 2016 Lucia Caspani et al., published by De Gruyter Open. (60 refs.)Main Heading: Quantum theoryControlled terms: Degrees of freedom (mechanics) - Microcavities - Photons - Quantum computers - Quantum opticsUncontrolled terms: Communication distance - Information transfers - Integrated platform - Optical microcavities - Polarization degree - Quantum Computing - Quantum correlated - Quantum photonicsClassification Code: 714 Electronic Components and TubesElectronic Components and Tubes - 722 Computer Systems and EquipmentComputer Systems and Equipment - 931 Classical Physics; Quantum Theory; RelativityClassical Physics; Quantum Theory; Relativity
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Guest Editorial Special Section on Learning in Non-(geo)metric Spaces
Pelillo, Marcello1; Hancock, Edwin R.2; Li, Xuelong3; Murino, Vittorio4 Source: IEEE Transactions on Neural Networks and Learning Systems, v 27, n 6, p 1290-1293, June 2016
; ISSN: 2162237X, E-ISSN: 21622388; DOI: 10.1109/TNNLS.2016.2522770; Article number: 7470326;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 Department of Environmental Sciences, Informatics and Statistics Ca, University of Venice, Via Torino 155, Venezia Mestre; 30172, Italy2 Department of Computer Science, University of York, York; YO105GH, United Kingdom3 Xian Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xian; 710119, China4 Pattern Analysis and Computer Vision, Istituto Italiano di Tecnologia, Genova; 16163, Italy
Abstract: Traditional machine learning and pattern recognition techniques are intimately linked to the notion of feature spaces. Adopting this view, each object is described in terms of a vector of numerical attributes and is, therefore, mapped to a point in a Euclidean (geometric) vector space, so that the distances between the points reflect the observed (dis)similarities between the respective objects. This kind of representation is attractive because geometric spaces offer powerful analytical as well as computational tools that are simply not available in other representations. Indeed, classical machine learning methods are tightly related to geometrical concepts, and numerous powerful tools have been developed during the last few decades, starting from the maximal likelihood method in the 1920s to perceptrons in the 1960s and, more recently, to kernel machines and deep learning architectures. © 2012 IEEE.
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Optical waveform monitoring based on a free-running mode-locked femtosecond fibre laser and four-wave mixing in a highly nonlinear fibre
Liu, Y.1; Zhang, J.-G.2; Tang, D.3 Source: Opto-electronics Review, v 24, n 2, p 62-74, June 1, 2016
; ISSN: 12303402, E-ISSN: 18963757; DOI: 10.1515/oere-2016-0010;
Publisher: De Gruyter Open LtdAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, Shaanxi; 710119, China2 Biomedical Engineering and Communications Research Group, School of Engineering, London South Bank University, 103 Borough Road, London; SE1 0AA, United Kingdom3 Southwest China Research Institute of Electronic Equipment, Chengdu; 610036, China
Abstract: Optical sampling based on ultrafast optical nonlinearities is a useful technique to monitor the waveforms of ultrashort optical pulses. In this paper, we present a new implementation of optical waveform sampling systems by employing our newly constructed free-running mode-locked fibre laser with a tunable repetition rate and a low timing jitter, an all-optical waveform sampler with a highly nonlinear fibre (HNLF), and our developed computer algorithm for optical waveform display and measurement, respectively. Using a femtosecond fibre laser to generate the highly stable optical sampling pulses and exploiting the four-wave mixing effect in a 100m-long HNLF, we successfully demonstrate the all-optical waveform sampling of a 10GHz optical clock pulse sequence with a pulse width of 1.8 ps and a 80Gbit/s optical data signal, respectively. The experimental results show that waveforms of the tested optical pulse signals are accurately reproduced with a pulse width of 2.0 ps. This corresponds to a temporal resolution of 0.87 ps for optical waveform measurement. Moreover, the optical eye diagram of a 10Gbit/s optical data signal with a 1.8 ps pulse width is also accurately measured by employing our developed optical sampling system. © 2016 by Walter de Gruyter Berlin/Boston. (22 refs.)Main Heading: Nonlinear opticsControlled terms: Algorithms - Fiber lasers - Fibers - Four wave mixing - Laser pulses - Locks (fasteners) - Mode-locked fiber lasers - Optical data processing - Signal sampling - Timing jitter - Ultrashort pulsesUncontrolled terms: All-optical waveforms - Eye diagrams - Femtosecond fibre lasers - Highly non-linear fibres - Optical nonlinearity - Optical sampling - Optical waveform - Ultrashort optical pulseClassification Code: 723.2 Data Processing and Image ProcessingData Processing and Image Processing - 741.1.1 Nonlinear OpticsNonlinear Optics - 744.1 Lasers, GeneralLasers, General - 744.4 Solid State LasersSolid State Lasers
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


A numerical algorithm to evaluate the transient response for a synchronous scanning streak camera using a time-domain Baum–Liu–Tesche equation
Pei, Chengquan1; Tian, Jinshou2; Wu, Shengli1; He, Jiai3; Liu, Zhen1 Source: Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, v 832, p 8-14, October 1, 2016
; ISSN: 01689002; DOI: 10.1016/j.nima.2016.06.061;
Publisher: ElsevierAuthor affiliation: 1 Key Laboratory for Physical Electronics and Devices of the Ministry of Education, Xi'an Jiaotong University, Xi'an; 710049, China2 Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China3 School of Computer and Communication, Lanzhou University of Technology, Lanzhou; Gansu; 730050, China
Abstract: The transient response is of great influence on the electromagnetic compatibility of synchronous scanning streak cameras (SSSCs). In this paper we propose a numerical method to evaluate the transient response of the scanning deflection plate (SDP). First, we created a simplified circuit model for the SDP used in an SSSC, and then derived the Baum–Liu–Tesche (BLT) equation in the frequency domain. From the frequency-domain BLT equation, its transient counterpart was derived. These parameters, together with the transient-BLT equation, were used to compute the transient load voltage and load current, and then a novel numerical method to fulfill the continuity equation was used. Several numerical simulations were conducted to verify this proposed method. The computed results were then compared with transient responses obtained by a frequency-domain/fast Fourier transform (FFT) method, and the accordance was excellent for highly conducting cables. The benefit of deriving the BLT equation in the time domain is that it may be used with slight modifications to calculate the transient response and the error can be controlled by a computer program. The result showed that the transient voltage was up to 1000 V and the transient current was approximately 10 A, so some protective measures should be taken to improve the electromagnetic compatibility. © 2016 Elsevier B.V. (20 refs.)Main Heading: Power qualityControlled terms: Algorithms - Electromagnetic compatibility - Frequency domain analysis - Numerical methods - Scanning - Streak cameras - Time domain analysis - Transient analysis - TransientsUncontrolled terms: Continuity equations - Frequency domains - Novel numerical methods - Numerical algorithms - Protective measures - Synchronous scanning - Transient current - Transient voltageClassification Code: 706.1.2 Electric Power DistributionElectric Power Distribution - 711.1 Electromagnetic Waves in Different MediaElectromagnetic Waves in Different Media - 742.2 Photographic EquipmentPhotographic Equipment - 921 MathematicsMathematics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Analysis and calibration of precision for point source transmittance system
Li, Zhao-Hui1, 2; Zhao, Jian-Ke1; Xu, Liang1; Liu, Feng1; Guo, Yi1; Liu, Kai1; Zhao, Qing1, 2 Source: Wuli Xuebao/Acta Physica Sinica, v 65, n 11, June 5, 2016; Language: Chinese
; ISSN: 10003290; DOI: 10.7498/aps.65.114206; Article number: 114206;
Publisher: Institute of Physics, Chinese Academy of SciencesAuthor affiliation: 1 Xi'an Institute of Optics and Precision Mechanics of Chinese Academy of Sciences, Xi'an; 710119, China2 University of Chinese Academy of Sciences, Beijing; 100049, China
Abstract: Owing to space optical system working for a long time outside the field of view, where there is strong background radiation, and the fact that the point source transmittance (PST) is an important evaluation indicator for stray light suppression of this optical system, the development of stray light equipment for testing PST has received more and more attention. Though the development of PST testing system has been extensively studied, none of them elaborate on the calibration of the PST testing system. Besides, most of the PST testing systems are at a laboratory research stage, and the calibration of neither testing stability nor accuracy is recognized. Therefore, on the basis of the PST testing system established, one calibration lens is designed to calibrate the PST testing system. By comparing the measured PST values of the calibration lens with the analyzed values, the PST testing system can be evaluated. The calibration lens model is built to analyze PST values at different off-axis angles by using the ray tracing software Tracepro. We consider the accuracy of modeling, and on the basis of simplifying the structure design, we measure bidirectional reflectance distribution function values of the painted surface of the calibration lens, and then estimate values of lens surface fromHarvey-Shack model and PSD theory by taking these property data into the model of simulation. Ultimately PST analyzed values of calibration lens can be obtained. Finally, by comparing the measured values of calibration lens, which are tested by using PST testing system, with the analyzed values, the calibration of the PST testing system is completed. In the PST testing process of calibration lens, by analyzing the data at different off-axis angles, the accuracy of repeated measurements and threshold of PST testing system can be obtained. At the same time, testing errors caused by the stability of light source, detector linearity, air scattering and structure of double cylindrical chamber are analyzed through the testing data. The data show that when double cylindrical chamber clean class is ISO 7, the PST threshold of this equipment is 10-8, and the accuracy of repeated measurements is 7.9%. Taking into account the detection capability, the PST threshold of this equipment is 10-10when environmental condition is better than ISO 6. © 2016 Chinese Physical Society. (14 refs.)Main Heading: CalibrationControlled terms: Distribution functions - Equipment - Light sources - Optical systems - Ray tracing - Stray lightUncontrolled terms: Bidirectional reflectance distribution functions - Cylindrical chambers - Environmental conditions - Evaluation indicators - Point sources - Precision - Repeated measurements - Stray light suppressionClassification Code: 741.1 Light/OpticsLight/Optics - 741.3 Optical Devices and SystemsOptical Devices and Systems - 901 Engineering ProfessionEngineering Profession - 922.1 Probability TheoryProbability Theory
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Study of aberration characteristic of off-axis reflective system
Pang, Zhihai1; Fan, Xuewu1; Ren, Guorui1; Ding, Jiaoteng1; Xu, Liang1; Feng, Liangjie1 Source: Hongwai yu Jiguang Gongcheng/Infrared and Laser Engineering, v 45, n 6, June 25, 2016; Language: Chinese
; ISSN: 10072276; DOI: 10.3788/IRLA201645.0618002; Article number: 0618002;
Publisher: Chinese Society of AstronauticsAuthor affiliation: 1 Space Optics Laboratory, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China
Abstract: Based on the 3rd vector wavefront aberration theory of axial symmetry optical system, the vector aberration expansions of off-axis optical system was obtained by pupil zoomed factorial and pupil decenter vector in this paper. It is known through the analysis that the off-axis optical system's aberration are still composed of 3rd spherical aberration 3rd coma and 3rd astigmatism. Due to the impact of pupil zoomed factorial, the decrease of the off-axis optical system's aberration coefficients were different proportion. The higher-order pupil aberration of coaxial system will induce low-order pupil aberration into off-axis mirror system. For example, if the coaxial system is not corrected for 3rd spherical aberration, it will introduce not only the spherical but also the constant coma and astigmatism into off-axis system. The aberration of off-axis system will not be asymmetry by the field center because the induced low-order aberration, and there maybe have an aberration zero point outside the center field of the view. © 2016, Editorial Board of Journal of Infrared and Laser Engineering. All right reserved. (9 refs.)Main Heading: Optical systemsControlled terms: Aberrations - Aspherics - Mirrors - Spheres - Vectors - WavefrontsUncontrolled terms: Aberration coefficients - Different proportions - Off-axis mirrors - Pupil aberrations - Reflective systems - Spherical aberrations - Vector aberration - Wavefront aberrationsClassification Code: 741.1 Light/OpticsLight/Optics - 741.3 Optical Devices and SystemsOptical Devices and Systems - 921.1 AlgebraAlgebra
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Optical trapping force and torque on spheroidal Rayleigh particles with arbitrary spatial orientations
Li, Manman1, 2; Yan, Shaohui1; Yao, Baoli1; Liang, Yansheng1; Han, Guoxia1; Zhang, Peng1 Source: Journal of the Optical Society of America A: Optics and Image Science, and Vision, v 33, n 7, p 1341-1347, July 1, 2016
; ISSN: 10847529, E-ISSN: 15208532; DOI: 10.1364/JOSAA.33.001341;
Publisher: OSA - The Optical SocietyAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China2 University of Chinese Academy of Sciences, Beijing; 100049, China
Abstract: We investigate the spatial orientation dependence of optical trapping forces and intrinsic torques exerted on spheroidal Rayleigh particles under irradiation of highly focused linearly and circularly polarized beams. It is revealed that the maximal trapping forces and torques strongly depend on the orientation of the spheroid, and the spheroidal particle is driven to be stably trapped at the beam focus with its major axis perpendicular to the optical axis. For a linearly polarized trapping beam, the optical torque is always perpendicular to the plane containing the major axis and the polarization direction of the incident beam. Therefore, the spheroid tends to rotate its major axis along with the polarization direction. However, for a circularly polarized trapping beam, the optical torque is always perpendicular to the plane containing the major axis and the optical axis. What is different from the linear polarization case is that the spheroid tends to have the major axis parallel to the projection of the major axis in the transverse plane. The optical torque in the circular polarization case is half of that in the linear polarization case. These optical trapping properties may be exploited in practical optical manipulation, especially for the nonspherical particle's trapping. © 2016 Optical Society of America. (33 refs.)Main Heading: Optical propertiesControlled terms: Circular polarization - Flight dynamics - Polarization - TorqueUncontrolled terms: Circularly polarized - Circularly polarized beam - Nonspherical particle - Optical manipulation - Optical trapping force - Polarization direction - Spatial orientations - Spheroidal particlesClassification Code: 711 Electromagnetic WavesElectromagnetic Waves - 741.1 Light/OpticsLight/Optics - 931.2 Physical Properties of Gases, Liquids and SolidsPhysical Properties of Gases, Liquids and Solids
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Stability of phase compensator in near-infrared polarized interferometer
Xie, Zheng-Mao1; Qi, Wen-Bo1; Wu, Guo-Jun1; He, Jun-Hua1 Source: Guangzi Xuebao/Acta Photonica Sinica, v 45, n 9, September 1, 2016; Language: Chinese
; ISSN: 10044213; DOI: 10.3788/gzxb20164509.0923003; Article number: 0923003;
Publisher: Chinese Optical SocietyAuthor affiliation: 1 Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China
Abstract: Phase compensator is a key element in the polarized interferometer, whose stability has a directive influence on the reliability of the polarized interference spectroscopy. The specification of the phase compensator such as the relative sensitivity of optical path difference, the tilted error tolerance of optical wedge, the oblique incidence angle error tolerance and the temperature adaptability were studied, and the corresponding calculated formulas were derived. The anti-interference ability of the moving optical wedge is 2/Δnsinθ times stronger than the classical Michelson interferometer. The ability of the moving wedge to resist the inclination is 1.75/Δn times higher than classic Michelson interferometer. After light's incidence with small angle, there are no additional optical path. The greatest optical path distance error of the phase compensator is 1.8 μm when the temperature changes from -20℃ to 85℃, which has a good thermal stability. The angle of the wedge is also an important parameter to affect the phase compensator. If setting the angle of the wedge as 30°, a good balance between performance, size and cost may be achieved. The birefringence difference of crystal material is smaller than one, so the stability advantages of the polarized interferometer are very obvious which build up a good basis for its field application with complicated surroundings. © 2016, Science Press. All right reserved. (14 refs.)Main Heading: Adaptive opticsControlled terms: Convergence of numerical methods - Errors - Infrared devices - Interferometers - Michelson interferometers - Near infrared spectroscopy - Spectroscopy - StabilityUncontrolled terms: Error tolerance - Interference spectroscopy - Near infrared spectra - Optical path difference - Optical path distances - Phase compensator - Polarized interferometer - Relative sensitivityClassification Code: 741.1 Light/OpticsLight/Optics - 921.6 Numerical MethodsNumerical Methods - 941.3 Optical InstrumentsOptical Instruments
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


High-power, high-efficiency 808 nm laser diode array
Wang, Zhen-Fu1; Yang, Guo-Wen1, 2; Wu, Jian-Yao2; Song, Ke-Chang2; Li, Xiu-Shan1; Song, Yun-Fei1 Source: Wuli Xuebao/Acta Physica Sinica, v 65, n 16, August 20, 2016; Language: Chinese
; ISSN: 10003290; DOI: 10.7498/aps.65.164203; Article number: 164203;
Publisher: Institute of Physics, Chinese Academy of SciencesAuthor affiliation: 1 Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China2 Xi'an Lumcore Optoelectronics Technologies Co., Ltd, Xi'an; 710077, China
Abstract: High-power, high-efficiency 808 nm laser diode arrays for pumping solid-state lasers have been widely used in industrial, scientific, medical and biological applications. The tendency of development of 808 nm laser diode pumping with high power, high efficiency and long lifetime is well-known. Diode-pumped solid-state system with high-efficiency laser diode array has many advantages such as compact volume, lower weight and energy saving. Currently, commercial 808 nm diode laser arrays with lower power conversion efficiency of about 50%-55%, due to the optical absorption losses for GaAs-based epitaxial materials, have been reported. In order to reduce series resistance and thermal resistance, heavily doped p-type waveguide and cladding layers are employed. However, the absorption loss on the free carriers in heavily doped p-type layers is dominant, leading to a lower power conversion efficiency. In order to achieve a high efficiency, the following requirements must be considered: improving the internal quantum efficiency by reducing the carrier leakage and increasing the electron injection efficiency; minimizing the voltage drop by optimizing the operating voltage; reducing the series resistance and thermal resistance of device; minimizing the internal loss including free-carrier absorption loss and scattering loss by designing optimized waveguide and cladding structure. In this paper, optimizing the epitaxial structure and fabricating technologies are demonstrated to achieve the high efficiency and high power. The asymmetric broad waveguide epitaxial structure with lower absorption loss in p-type waveguide and cladding layer is designed in order to achieve the above goals. The high-efficiency epitaxial structure is optimized including the thickness, doping and composition for each layer structure. The strained quantum well diode laser with lower transparency current and higher differential is of benefit to achieving the high power. A novel asymmetric broad waveguide structure is designed by optimizing the waveguide thickness and component of p-waveguide so as to reduce carrier absorption loss, the optical absorption loss in this epitaxial structure is achieved to be as low as 0.63 cm-1. The wafer is grown by metalorganic chemical vapor deposition on an n-GaAs substrate. The optimized growth conditions and substrates orientation are extensively studied to improve the crystal quality and reduce the internal loss and defects. The wafer is processed using standard procedures. For the fabricated 1-cm laser diode array mounted on P-side down on copper microchannel cooled heatsink, the device shows an output power of 150 W under an operating current of 135 A with an emitting wavelength of 809 nm, an operating voltage of 1.76 V, a slope efficiency of as high as 1.25 W/A, and maximum power conversion efficiency of as high as 65.5%, which is the highest level of 808 nm diode laser array with an output power of 150 W. © 2016 Chinese Physical Society. (17 refs.)Main Heading: Quantum efficiencyControlled terms: Conversion efficiency - Crystal orientation - Crystallography - Diodes - Electric resistance - Electromagnetic wave absorption - Energy conservation - Gallium arsenide - Light absorption - Metallorganic chemical vapor deposition - Pumping (laser) - Quantum well lasers - Semiconducting gallium - Semiconductor lasers - Semiconductor quantum wells - Solid state lasers - Substrates - WaveguidesUncontrolled terms: Absorption loss - Biological applications - Free carrier absorption - Internal quantum efficiency - Laser diode arrays - Microchannel cooled heatsink - Power conversion efficiencies - Strained quantum wellsClassification Code: 525.2 Energy ConservationEnergy Conservation - 525.5 Energy Conversion IssuesEnergy Conversion Issues - 701.1 Electricity: Basic Concepts and PhenomenaElectricity: Basic Concepts and Phenomena - 711 Electromagnetic WavesElectromagnetic Waves - 712.1.1 Single Element Semiconducting MaterialsSingle Element Semiconducting Materials - 714.2 Semiconductor Devices and Integrated CircuitsSemiconductor Devices and Integrated Circuits - 714.3 WaveguidesWaveguides - 741.1 Light/OpticsLight/Optics - 744 LasersLasers - 802.2 Chemical ReactionsChemical Reactions - 804 Chemical Products GenerallyChemical Products Generally - 931.4 Quantum Theory; Quantum MechanicsQuantum Theory; Quantum Mechanics - 933.1 Crystalline SolidsCrystalline Solids - 933.1.1 Crystal LatticeCrystal Lattice
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Thermal-structural coupled analysis and verification of 2-D mirror gimbal for lunar-based telescope
Shangguan, Ai-Hong1, 2; Wang, Chen-Jie1, 3; Zhang, Hao-Su1, 2; Qin, De-Jin1; Liu, Zhao-Hui1 Source: Guangxue Jingmi Gongcheng/Optics and Precision Engineering, v 24, n 8, p 1956-1964, August 1, 2016; Language: Chinese
; ISSN: 1004924X; DOI: 10.3788/OPE.20162408.1956;
Publisher: Chinese Academy of SciencesAuthor affiliation: 1 Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China2 University of Chinese Academy of Sciences, Beijing; 100049, China3 Key laboratory of Thermo-Fluid Science and Engineering of the Ministry of Education, Xi'an Jiaotong University, Xi'an; 710049, China
Abstract: To improve the work performance of a 2-D mirror gimbal for the lunar-based telescope, the thermal-structural coupled analysis was carried out, and the analysis results were verified by thermal and onboard tests. According to the given input conditions, thermal loads and the thermal boundary, the finite element model was established to calculate the temperature fields of the mirror gimbal and main heating components. Through inputting the temperature loads, preloads and the boundary conditions into the finite element model, the thermal deformation and stress of the U-shape structure, precision moving shafting systems and the worm gears were obtained. Then, the expressions of friction moment were derived, and analytical data were used to the expressions to achieve the friction moment of shafting systems. On the basis of the friction moment, a proper moment motor was chosen. After calculation, the results show that the left shafting system has a larger friction moment at the low temperature condition of -25℃, and the maximal one is up to 14.163 N·mm; While the friction moment is smaller under high temperature condition 55℃, and the maximal one is 4.796 N·mm. The results also show friction moment of the azimuth shafting systems at a low temperature condition of -25℃ is 16.45 N·mm. Moreover, the vertical shaft system shows its friction moment to be 16.45 N·mm at the low temperature condition of -25℃, while it is zero at the high temperature condition because of shafting system unloading. The results indicate the reflection mirror gimbal works well between -25℃ to 55℃. Finally, the thermal and onboard tests were carried out to demonstrate the rationality and validity of the analysis results. © 2016, Science Press. All right reserved. (13 refs.)Main Heading: Finite element methodControlled terms: Deformation - Friction - Mirrors - Moon - Optical testing - Structural analysis - Telescopes - Temperature - Thermal stress - Tribology - Unloading - Uranium - Worm gearsUncontrolled terms: Coupled analysis - Friction moment - High temperature condition - Low temperature conditions - Reflection mirrors - Temperature loads - Thermal deformation - Work performanceClassification Code: 408.1 Structural Design, GeneralStructural Design, General - 547 Minor, Precious and Rare Earth Metals and AlloysMinor, Precious and Rare Earth Metals and Alloys - 601.2 Machine ComponentsMachine Components - 641.1 ThermodynamicsThermodynamics - 657.2 Extraterrestrial Physics and Stellar PhenomenaExtraterrestrial Physics and Stellar Phenomena - 691.2 Materials Handling MethodsMaterials Handling Methods - 741.3 Optical Devices and SystemsOptical Devices and Systems - 921.6 Numerical MethodsNumerical Methods - 931 Classical Physics; Quantum Theory; RelativityClassical Physics; Quantum Theory; Relativity - 931.2 Physical Properties of Gases, Liquids and SolidsPhysical Properties of Gases, Liquids and Solids
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Two side liquid-cooled and passively Q-switched disk oscillator with nanosheets in flowing CCl4
Nie, Rongzhi1, 2; She, Jiangbo1; Li, Dongdong4; Li, Fuli2; Peng, Bo1, 3 Source: Applied Physics B: Lasers and Optics, v 122, n 9, September 1, 2016
; ISSN: 09462171; DOI: 10.1007/s00340-016-6519-4; Article number: 241;
Publisher: Springer VerlagAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi’an Institute of Optics and Precision Mechanics, Chinese Academy of Science (CAS), Xi’an; 710119, China2 School of Science, Xi’an Jiaotong University, Xi’an; 710119, China3 Key Laboratory for Organic Electronics and Information Displays, Institute of Advanced Materials (IAM), Nanjing University of Posts and Telecommunications, Nanjing; Jiangsu; 210046, China4 School of Electronic Engineering, Xi’an University of Post and Telecommunications, Xi’an; 710121, China
Abstract: A passively Q-switched and two side liquid-cooled Nd:YAG disk oscillator is demonstrated, which is operated at a pump pulse width of 300 μs and a pump repetition rate of 10 Hz. The coolant flows over the two large surfaces of the disk and will be passed through by laser beam, so it can also serve as a saturable absorber. For the unmodulated laser, the pure CCl4was employed as coolant and a plane output mirror of 15 % transmission was employed. The maximum output energy of 795 mJ is realized corresponding to the optical–optical efficiency of 27.4 % and the slope efficiency of 30 %; for the graphene Q-switched laser, the CCl4with graphene nanosheets was employed as coolant and a plane output mirror of 40 % transmission was employed. The maximum output energy of 376 mJ is realized corresponding to the optical–optical efficiency of 13 % and the slope efficiency of 18 %. The maximum average Q-switching repetition rate is 385 kHz, and the minimum average pulse width is 116 ns; for the MoS2Q-switched laser, the CCl4with MoS2nanosheets was employed as coolant and a plane output mirror of 30 % transmission was employed. The maximum output energy of 486 mJ is realized corresponding to the optical–optical efficiency of 17 % and the slope efficiency of 22 %.The maximum average Q-switching repetition rate is 470 kHz, and the minimum average pulse width is 137 ns. © 2016, Springer-Verlag Berlin Heidelberg. (21 refs.)Main Heading: Q switchingControlled terms: Absorption refrigeration - Coolants - Energy efficiency - Graphene - Laser beams - Laser mirrors - Mirrors - Molybdenum compounds - Nanosheets - Optical pumping - Pulse repetition rate - Q switched lasers - Saturable absorbersUncontrolled terms: Graphene nanosheets - Large surfaces - Optical efficiency - Output mirrors - Passively Q-switched - Pump pulse width - Repetition rate - Slope efficienciesClassification Code: 525.2 Energy ConservationEnergy Conservation - 644.1 Refrigeration MethodsRefrigeration Methods - 741.3 Optical Devices and SystemsOptical Devices and Systems - 744.1 Lasers, GeneralLasers, General - 744.8 Laser Beam InteractionsLaser Beam Interactions - 761 NanotechnologyNanotechnology - 803 Chemical Agents and Basic Industrial ChemicalsChemical Agents and Basic Industrial Chemicals - 804 Chemical Products GenerallyChemical Products Generally - 933 Solid State PhysicsSolid State Physics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


KW-level low photodarkening Yb/Ce codoped aluminosilicate fiber fabricated by the chelate gas phase deposition technique
Zhang, Lihua1; Li, Gang1; Li, Weinan1; Gao, Qi1; Li, Zhe1; Zhao, Wei1; Zhao, Baoyin1; Hou, Chaoqi1 Source: Optical Materials Express, v 6, n 11, p 3558-3564, 2016; E-ISSN: 21593930; DOI: 10.1364/OME.6.003558;
Publisher: OSA - The Optical SocietyAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences (CAS), Xi'an; 710119, China
Abstract: A Yb/Ce codoped aluminosilicate fiber was successfully fabricated by the chelate gas phase deposition technique. Using the homemade fiber as the amplifier stage in a master oscillator power amplifier configuration laser setup, a near single mode laser output (M2= 1.55) with an output power of 1026 W and slope efficiency of 84.8% is obtained. In the 100 hour photodarkening experiment, the entire reduced power is less than 14 W, and the ratio, compared to the initial 1026 W output power, is less than 1.4%. The investigation of optical properties indicates that Yb/Ce codoped aluminosilicate fiber fabricated by the chelate gas phase deposition technique shows homogenous distribution, appropriate absorption coefficient, low background attenuation, high optical-to-optical efficiency and a rather low photodarkening loss, making it a promising candidate as an active fiber for a reliable and efficient fiber laser in high-power applications. © 2016 Optical Society of America. (24 refs.)Main Heading: Fiber amplifiersControlled terms: Aluminosilicates - Chelation - Deposition - Efficiency - Fabrication - Fiber lasers - Fibers - Gases - Optical properties - Power amplifiers - YtterbiumUncontrolled terms: Absorption co-efficient - Aluminosilicate fibers - Gas-phase deposition techniques - High power applications - Master oscillator power amplifiers - Optical-to-optical efficiency - Single-mode lasers - Slope efficienciesClassification Code: 547.2 Rare Earth MetalsRare Earth Metals - 713.1 AmplifiersAmplifiers - 741.1 Light/OpticsLight/Optics - 744.4 Solid State LasersSolid State Lasers - 802.2 Chemical ReactionsChemical Reactions - 802.3 Chemical OperationsChemical Operations - 913.1 Production EngineeringProduction Engineering
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Dynamic characteristic analysis on streak image tube with high temporal resolution
Liu, Rong1, 2; Tian, Jin-Shou2; Miao, Run-Cai1; Wang, Qiang-Qiang2; Wen, Wen-Long2; Li, Yan3; Wang, Jun-Feng2; Xu, Xiang-Yan2; Lu, Yu2; Liu, Hu-Lin2; Wang, Xing2 Source: Guangzi Xuebao/Acta Photonica Sinica, v 45, n 10, October 1, 2016; Language: Chinese
; ISSN: 10044213; DOI: 10.3788/gzxb20164510.1012001; Article number: 1012001;
Publisher: Chinese Optical SocietyAuthor affiliation: 1 School of Optoelectronic Engineering, Xi'an Technological University, Xi'an; 710032, China2 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Science, Xi'an; 710119, China3 School of Science, Xi'an Shiyou University, Xi'an; 710065, China
Abstract: Aim to high temporal resolution of the streak image tube in streak camera, the factors which influence the physical temporal dispersion, technical temporal dispersion and time jitter of the sweep circuit were discussed. The streak image tube was optimized, in which a pair of traveling wave deflectors was located before a magnetic solenoid lens. The inner time-varying electric field of traveling wave deflectors was simulated by CST electromagnetic studio. And the propagation velocity of electromagnetic wave was calculated. The results show that when leg length is 8 mm, leg width is 1mm, interval is 0.24 mm, pin length is 2.5 mm, deflector thickness is 1 mm and deflector length is 17.12 mm, the moving velocity of electrons and propagation velocity of the electromagnetic wave are matching. Based on the electron trajectory tracing method and the Rayleigh criterion, dynamic temporal and spatial characteristics of the streak image tube were analyzed, a dynamic temporal resolution of 200 fs in single sweep mode, dynamic temporal resolution of 208 fs in synchronized sweep mode, and a dynamic spatial resolution of above 20 lp/mm were obtained. © 2016, Science Press. All right reserved. (15 refs.)Main Heading: Image storage tubesControlled terms: Circular waveguides - Dispersion (waves) - Electric fields - Electromagnetic waves - Image analysis - Image converters - Image resolution - Optical transfer function - Rayleigh scattering - Tubes (components)Uncontrolled terms: Dynamic characteristics - Rayleigh criterion - Spatial resolution - Streak image tube - Temporal resolution - Ultrafast opticsClassification Code: 619.1 Pipe, Piping and PipelinesPipe, Piping and Pipelines - 701.1 Electricity: Basic Concepts and PhenomenaElectricity: Basic Concepts and Phenomena - 711 Electromagnetic WavesElectromagnetic Waves - 714.1 Electron TubesElectron Tubes - 714.3 WaveguidesWaveguides - 741.1 Light/OpticsLight/Optics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Non-contact photoelectric angle measurement based on gyrorotor
Wang, Xianhua1; Jia, Sen1; Gao, Limin1; Xiao, Maosen1; Wu, Yiming1 Source: Zhongguo Jiguang/Chinese Journal of Lasers, v 43, n 10, October 10, 2016; Language: Chinese
; ISSN: 02587025; DOI: 10.3788/CJL201643.1004001; Article number: 1004001;
Publisher: Science PressAuthor affiliation: 1 Laboratory of Optical Directiona and Measurement Technology, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; Shaanxi; 710119, China
Abstract: A non-contact angle measurement method based on gyrorotor with periodical pattern surface is proposed. By using photoelectric sensors to detect the information from periodical pattern surface of gyrorotor, we can measure the deflection angle of gyrorotor in real time. The angle measurement principle and its device are introduced. By constructing three-dimensional geometrical models, the angle decoding algorithm of the angle measurement method is derived in detail, and the curves or the surfaces of the relationships between the gyrorotor's pattern surface information detected by photoelectric sensors and the angle deflections (calculated under the conditions that the gyrorotor is without deflection, with one-dimensional deflection and with two-dimensional deflection respectively) are obtained. The results show that the deflection angle and the deflection direction of gyrorotor can be measured by two photoelectric sensors in orthogonal directions, and the measurement values are unique and the measurement range of deflection angle is larger than 30°. This method can be used to measure angle deflection both in static and high-speed dynamic measurements. © 2016, Chinese Lasers Press. All right reserved. (12 refs.)Main Heading: Deflection (structures)Controlled terms: Angle measurement - Measurements - Photoelectricity - Three dimensional computer graphicsUncontrolled terms: Decoding algorithm - Geometrical models - Gyro-rotor - Measurement methods - Measurement range - Noncontact measurements - Orthogonal directions - Photoelectric sensorsClassification Code: 408.2 Structural Members and ShapesStructural Members and Shapes - 701.1 Electricity: Basic Concepts and PhenomenaElectricity: Basic Concepts and Phenomena - 723.2 Data Processing and Image ProcessingData Processing and Image Processing - 943.2 Mechanical Variables MeasurementsMechanical Variables Measurements
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


High peak power mid-infrared 2.8 μm pulsed fiber laser
Shen, Yan-Long1, 2; Wang, Yi-Shan2, 3; Chen, Hong-Wei1; Huang, Ke1; Tao, Meng-Meng1; Luan, Kun-Peng1; Yu, Li1; Yi, Ai-Ping1; Feng, Guo-Bin1 Source: Guangzi Xuebao/Acta Photonica Sinica, v 45, n 11, November 1, 2016; Language: Chinese
; ISSN: 10044213; DOI: 10.3788/gzxb20164511.1114002; Article number: 1114002;
Publisher: Chinese Optical SocietyAuthor affiliation: 1 State Key Laboratory of Laser Interaction with Matter, Northwest Institute of Nuclear Technology, Xi'an; 710024, China2 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China3 Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan; 030006, China
Abstract: A high peak power actively Q-switched mid-infrared fiber laser at 2.8 μm was demonstrated with a repetition rate of 1~10 kHz by employing a 975 nm laser-diode to pump a piece of heavily Er3+-doped ZBLAN double-clad fiber and a mechanical chopper into the cavity as the Q-switch. Stable Q-switched laser pulse with a maximum pulse energy of 134.5 μJ, pulse duration of 127.3 ns and peak power of 1.1 kW was obtained at a repetition rate of 10 kHz under a proper pump power. © 2016, Science Press. All right reserved. (28 refs.)Main Heading: Pulsed lasersControlled terms: Choppers (circuits) - Erbium - Fiber lasers - Fibers - Infrared devices - Optical pumping - Pulse repetition rate - Pumping (laser) - Q switched lasers - Q switchingUncontrolled terms: Actively Q-switched - Double clad fibers - High peak power - Mechanical choppers - Midinfrared - Pulse durations - Pulsed fiber lasers - Repetition rateClassification Code: 547.2 Rare Earth MetalsRare Earth Metals - 744 LasersLasers
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Slow light and fast light in microfiber double-knot resonator with a parallel structure
Xu, Yiping1; Ren, Liyong2; Ma, Chengju3; Kong, Xudong2; Ren, Kaili2 Source: Applied Optics, v 55, n 30, p 8612-8617, October 20, 2016
; ISSN: 1559128X, E-ISSN: 21553165; DOI: 10.1364/AO.55.008612;
Publisher: OSA - The Optical SocietyAuthor affiliation: 1 School of Physics and Optoelectronic Engineering, Yangtze University, Jingzhou; 434023, China2 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China3 School of Science, Xi'an Shiyou University, Xi'an; 710065, China
Abstract: Based on the theoretical model of a microfiber double-knot resonator with a parallel structure, numerical simulations on the transmission spectrum, the phase, and the group time delay of the resonator as a function of wavelengths are given. We find that with this kind of resonator both slow light and fast light can be obtained at different resonant wavelengths. Experimentally, such a kind of microfiber resonator was fabricated successfully. The transmission spectrum of the fabricated resonator is well consistent with the theoretical simulation. A slow-light delay of about 38 ps and a fast-light advance of about 40 ps are demonstrated at different wavelengths, which might benefit the resonator to the applications in data delay lines, optical buffers, and optical memories. © 2016 Optical Society of America. (33 refs.)Main Heading: Slow lightControlled terms: Group delay - Resonators - Time delayUncontrolled terms: Micro-fiber - Optical buffer - Parallel structures - Resonant wavelengths - Slow-light delay - Theoretical modeling - Theoretical simulation - Transmission spectrumsClassification Code: 703.1 Electric NetworksElectric Networks - 713 Electronic CircuitsElectronic Circuits - 741.1 Light/OpticsLight/Optics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Simulating the spatial resolution of the framing camera
Bai, Xiaohong1; Zhu, Bingli1; Xu, Peng1; Wang, Bo1; Gou, Yongsheng1; Qin, Junjun1; Cao, Weiwei1; Liu, Baiyu1; Bai, Yonglin1 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 10141, 2016, Selected Papers of the Chinese Society for Optical Engineering Conferences held July 2016
; ISSN: 0277786X, E-ISSN: 1996756X; ISBN-13: 9781510607279; DOI: 10.1117/12.2255140; Article number: 1014118; Conference: 3rd International Symposium on Monitoring, Early Warning, Removal Technology of Space Targets and Debris, the 4th International Conference on Frontiers in Optical Imaging Technology and Applications, and the 2nd International Symposium on Photoelectric Defense Technologies, July 22, 2016 - July 26, 2016; Sponsor: China High-Tech Industrialization Association; Chinese Academy of Engineering; Chinese Society for Optical Engineering; National Natural Science Foundation of China;
Publisher: SPIEAuthor affiliation: 1 Key Laboratory of Ultrafast Diagnosis Technology, Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, Shaanxi; 710119, China
Abstract: The structural models of micro-channel plate (MCP) and fluorescent screen of the framing camera were established. By combining the finite element integration and Monte Carlo method, software Simion and Lorenz were respectively used to simulate the effects of different voltages loaded on the fluorescent screen, different closed distance between fluorescent screen and MCP, and electrode immersion depth at MCP output on the spatial resolution, in order to obtain an axisymmetric distribution curve. Results showed that the closed distance between MCP and fluorescent screen had the largest impact on the framing camera's spatial resolution. In addition, higher fluorescent screen voltage did not necessarily result in better spatial resolution, as it was influenced by the light-emitting mechanism of the fluorescent screen. At the framing camera's current closed distance of 0.8mm, a fluorescent screen voltage of 5000V could achieve the best spatial resolution. © 2016 SPIE. (9 refs.)Main Heading: Fluorescent screensControlled terms: Cameras - Computer simulation - Finite element method - Fluorescence - Image resolution - Image storage tubes - Imaging techniques - Light emission - Monte Carlo methods - Plates (structural components) - Space debrisUncontrolled terms: closed distance - Different voltages - Distribution curves - Emitting mechanisms - end spoiling - Micro channel plate - Spatial resolution - Structural modelsClassification Code: 408.2 Structural Members and ShapesStructural Members and Shapes - 656.1 Space FlightSpace Flight - 714.1 Electron TubesElectron Tubes - 723.5 Computer ApplicationsComputer Applications - 741.1 Light/OpticsLight/Optics - 741.3 Optical Devices and SystemsOptical Devices and Systems - 742.2 Photographic EquipmentPhotographic Equipment - 746 Imaging TechniquesImaging Techniques - 921.6 Numerical MethodsNumerical Methods - 922.2 Mathematical StatisticsMathematical Statistics
Database: Compendex
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Moving target detection based on features matching of RGB on a foggy day
Zhang, Ya-Qun1, 2; Song, Zong-Xi1 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 10033, 2016, Eighth International Conference on Digital Image Processing, ICDIP 2016
; ISSN: 0277786X, E-ISSN: 1996756X; ISBN-13: 9781510605039; DOI: 10.1117/12.2243963; Article number: 100330J; Conference: 8th International Conference on Digital Image Processing, ICDIP 2016, May 20, 2016 - May 23, 2016; Sponsor: Chengdu University of Information Technology; Chinese Academy of Sciences Chengdu Institute of Computer Applications; International Association of Computer Science and Information Technology; Sichuan Province Computer Federation;
Publisher: SPIEAuthor affiliation: 1 Xi'An Institute of Optics and Precision Mechanics of CAS, Xi'an; 710119, China2 University of Chinese Academy of Sciences, Beijing; 100049, China
Abstract: Moving target detection is a significant research content of image processing and computer vision. Precise detection of moving target is the basic of target positioning, target tracking and target classification. There are many applications of it in intelligent monitoring, traffic statistics and many other fields. How to detect the moving object in a bad weather, for example, a heavy foggy day, is a problem that needs be solved in the engineering, we all know that the haze has been a quite serious environment problem in our life! The paper is based on this. First, getting rid of fog in the video, and then, extracting the features of pixels, establishing features dictionaries, building models for background by features matching in order to extract foreground. The result shows that the proposed algorithm can detect the moving target accurately in a foggy day. © 2016 SPIE. (15 refs.)Main Heading: Image processingControlled terms: Computer vision - Image matching - Object detection - Target tracking - Tracking (position) - Traffic surveysUncontrolled terms: Background model - Features matching - Image processing and computer vision - Intelligent monitoring - Moving target detection - Target Classification - Traffic statistics - Video defoggingClassification Code: 432.4 Highway Traffic ControlHighway Traffic Control - 723.2 Data Processing and Image ProcessingData Processing and Image Processing - 723.5 Computer ApplicationsComputer Applications
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


The lightweight structure design of a CFRP mirror
Ding, Jiaoteng1; Xu, Liang1; Ma, Zhen1; Xie, Yongjie1; Luo, Yao2; Wang, Yongjie1; Pang, Zhihai1 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 9683, 2016, 8th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Advanced Optical Manufacturing Technologies
; ISSN: 0277786X, E-ISSN: 1996756X; ISBN-13: 9781628419184; DOI: 10.1117/12.2243440; Article number: 96831X; Conference: 8th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Advanced Optical Manufacturing Technologies, AOMATT 2016, April 26, 2016 - April 29, 2016; Sponsor: Chinese Academy of Sciences, Institute of Optics and Electronics (IOE); The Chinese Optical Society (COS);
Publisher: SPIEAuthor affiliation: 1 Xi'an Institute of Optics and Precision Mechanics of CAS, Shannxi Xi'an; 710119, China2 Xi'an Branch of China Academy of Space Technology, Shannxi Xi'an; 710100, China
Abstract: The advantage of Carbon Fiber Reinforced Polymer (CFRP) is obvious as a common space material for low density, low thermal expansion coefficient and high specific stiffness characteristics, it is the ideal material choice for space optical reflector. Mirror structure with honeycomb can achieve high rates of lightweight, as well as high specific stiffness. For Φ300mm CFRP mirror, accounting of the actual process properties of CFRP, mirror panels laminated based on thermal stability design, honeycomb fabricated using one innovative inlaying-grafting design method. Finally, lightweight structure design of the CFRP primary mirror completed, the thermal stability result of the Φ300mm CFRP mirror achieved is 10nm°C. © 2016 SPIE. (10 refs.)Main Heading: MirrorsControlled terms: Carbon - Carbon fiber reinforced plastics - Design - Fiber reinforced plastics - Grafting (chemical) - Honeycomb structures - Laminating - Manufacture - Stiffness - Thermal expansion - Thermodynamic stabilityUncontrolled terms: Carbon fiber reinforced polymer - High specific stiffness - Laminated - Lightweight - Lightweight structure designs - Low thermal expansion - Mirror structure - Process propertiesClassification Code: 408.2 Structural Members and ShapesStructural Members and Shapes - 537.1 Heat Treatment ProcessesHeat Treatment Processes - 641.1 ThermodynamicsThermodynamics - 741.3 Optical Devices and SystemsOptical Devices and Systems - 802.2 Chemical ReactionsChemical Reactions - 804 Chemical Products GenerallyChemical Products Generally - 816.1 Processing of Plastics and Other PolymersProcessing of Plastics and Other Polymers - 817.1 Polymer ProductsPolymer Products - 951 Materials ScienceMaterials Science
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Design of a mid-wavelength infrared dual field of view zoom system
Duan, Jing1; Li, Gang1, 2; Jiang, Kai1; Liu, Kai1; Yan, Peipei1, 2; Shan, Qiusha1 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 10154, 2016, Advanced Optical Design and Manufacturing Technology and Astronomical Telescopes and Instrumentation
; ISSN: 0277786X, E-ISSN: 1996756X; DOI: 10.1117/12.2246694; Article number: 1015416; Conference: International Symposium on Advanced Optical Design and Manufacturing Technologies and International Symposium on Astronomical Telescope and Instrumentation, May 9, 2016 - May 11, 2016; Sponsor: China High-Tech Industrialization Association (CHIA); Chinese Society for Optical Engineering (CSOE);
Publisher: SPIEAuthor affiliation: 1 Photoelectric Track and Measurement Technology Research Department, Xi'an Institute of Optics and Precision Mechanics, CAS, Shaanxi Xi'an; 710119, China2 University of the Chinese Academy of Sciences, Beijing; 100049, China
Abstract: In order to effectively improve the target detection and recognition ability of IR imagers, based on a 320×256 cooled staring focal plane array(FPA) detector, pixel size 30μm×30μm, a mid-wavelength infrared dual field of view zoom system was designed. In this paper, the working wavelength is 3μmï1/2ž5μm, the temperature range is-40°C∼+50°C, this system can realize 200mm and 400mm dual focal length, the F-number is 2, the full field of view of short focal length is 3.44° and long focal length is 1.72° respectively, satisfy 100% cold shield efficiency. A re-imaging refractive system was adopted in this designed optical system consists of main optics and projection components. First of all, the structural selection and the initial parameter calculation were introduced in detail. Secondly, on the basis of variety of the distance and temperature, a focusing lens was presented in this system to adjust to produce a clear image. Last but not the least, to improve image quality and environment adaptability, the analysis of temperature change and narcissus effect were described particularly. The design results prove that at the spatial frequency of 17 lp/mm, the MTF of the optical system is greater than 0.5(the axis MTF of the optical is greater than 0.6), the system can offer a high resolution and excellent images in whole range of the focal length, and it has the advantages of good adaptability, compact structure, high optical transmission and small size. © 2016 SPIE. (7 refs.)Main Heading: Optical designControlled terms: Cold working - Infrared radiation - Light transmission - Manufacture - Optical systems - Optical transfer function - Radio telescopes - TelescopesUncontrolled terms: Dual field of views - Infrared technology - Mid-wavelength infrared - Refractive systems - Short focal lengths - Target detection and recognition - Temperature changes - Zoom systemsClassification Code: 535.2 Metal FormingMetal Forming - 537.1 Heat Treatment ProcessesHeat Treatment Processes - 657.2 Extraterrestrial Physics and Stellar PhenomenaExtraterrestrial Physics and Stellar Phenomena - 741.1 Light/OpticsLight/Optics - 741.3 Optical Devices and SystemsOptical Devices and Systems
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Adaptive retinex algorithm based on genetic algorithm and human visual system
Song, Xiaodong1; Zhou, Zuofeng1; Guo, Huinan1; Zhao, Xiaodong1; Zhang, Hui1 Source: Proceedings - 2016 8th International Conference on Intelligent Human-Machine Systems and Cybernetics, IHMSC 2016, v 1, p 183-186, December 13, 2016, Proceedings - 2016 8th International Conference on Intelligent Human-Machine Systems and Cybernetics, IHMSC 2016; ISBN-13: 9781509007684; DOI: 10.1109/IHMSC.2016.27; Article number: 7783585; Conference: 8th International Conference on Intelligent Human-Machine Systems and Cybernetics, IHMSC 2016, September 11, 2016 - September 12, 2016;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Science, Xi'an, China
Abstract: Multi-scale retinex is a luminance perceptual algorithm. It is widely used in image enhancement. To get best effect, the parameters need be adjusted according to the scene manually. In order to handle this issue, a novel retinex algorithm based on real-coded genetic algorithm and human visual system was proposed in this paper. The result was quantified and selected by a novel human visual system based comprehensive fitness function. The employed fitness function operates adaptively and tends to provide outstanding comprehensive results in both image clarity and color quality. Images captured in low-light conditions were processed by proposed method. The result indicates that the new algorithm can improve image brightness and avoid color distortion at the same time. © 2016 IEEE. (10 refs.)Main Heading: Image processingControlled terms: Cybernetics - Genetic algorithms - Image enhancement - Luminance - Man machine systemsUncontrolled terms: Color distortions - Fitness functions - Human Visual System - Low light conditions - Multi-scale Retinex - Real coded genetic algorithm - Retinex algorithms - Self-adaptive
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Development and alignment for SiC mirror subsystem of a space-borne telescope
Feng, Liangjie1; Wang, Wei1; Ren, Guorui1 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 10154, 2016, Advanced Optical Design and Manufacturing Technology and Astronomical Telescopes and Instrumentation
; ISSN: 0277786X, E-ISSN: 1996756X; DOI: 10.1117/12.2247416; Article number: 1015425; Conference: International Symposium on Advanced Optical Design and Manufacturing Technologies and International Symposium on Astronomical Telescope and Instrumentation, May 9, 2016 - May 11, 2016; Sponsor: China High-Tech Industrialization Association (CHIA); Chinese Society for Optical Engineering (CSOE);
Publisher: SPIEAuthor affiliation: 1 XI'AN Institute of Optics and Precision Mechanics of CAS, Xi'an, Shanxi; 710119, China
Abstract: A Φ600mm SiC primary mirror subsystem of a space-borne Ritchey-Chretien telescope was designed. The open-back primary mirror was made of pressure-less sintering silicon carbide (SiC), light-weighted at a ratio of approximately 70%. Minimizing the optical surface astigmatism was critical for the mirror, the astigmatism is caused mainly by gravity effects, temperature variation and the bonding process. Three invar flexure bipods were fixed on the baseplate of the telescope at first, and the posture of the primary mirror was adjusted precisely for 0.2mm gap to the bipods. 3M 2216 B/A grey adhesive was then injected into the gap between the mirror and bipod flexure, the curing process was last 72 hours in the room temperature. So the mirror was affected only by curing stress of the adhesive during the assembly process. Structural strength and dynamic stiffness of the mirror subsystem in the thermal-structural coupling state were analyzed with finite element method. Analyzed results show that the optical surface distortion is less than 1/50 at 632.8nm RMS with three points support and less than 1/200λ RMS with 2°C temperature variation because of the flexure support and compatible support and mirror material, The optical performance test with interferometer show that the optical surface distortion caused by the curing stress of the adhesive is less than 1/50λRMS, the overall optical surface of the primary mirror is less than 1/30λ rms, which met the critical requirements for the primary mirror of the telescope. © 2016 SPIE. (7 refs.)Main Heading: Optical testingControlled terms: Curing - Finite element method - Manufacture - Mirrors - Optical design - Radio telescopes - Silicon carbide - Sintering - Telescopes - Temperature - Temperature distributionUncontrolled terms: bipod flexure - Curing stress - Optical surfaces - SiC mirrors - Space-borneClassification Code: 537.1 Heat Treatment ProcessesHeat Treatment Processes - 641.1 ThermodynamicsThermodynamics - 657.2 Extraterrestrial Physics and Stellar PhenomenaExtraterrestrial Physics and Stellar Phenomena - 741.1 Light/OpticsLight/Optics - 741.3 Optical Devices and SystemsOptical Devices and Systems - 802.2 Chemical ReactionsChemical Reactions - 804.2 Inorganic CompoundsInorganic Compounds - 921.6 Numerical MethodsNumerical Methods
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Stray light measurement for point source transmittance of space optical systems
Chen, Qinfang1; Ma, Zhen1; Li, Xinyao2; Pang, Zhihai1; Xu, Liang1; Li, Zhaohui1 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 9684, 2016, 8th International Symposium on Advanced Optical Manufacturing and Testing Technology: Optical Test, Measurement Technology, and Equipment
; ISSN: 0277786X, E-ISSN: 1996756X; ISBN-13: 9781628419191; DOI: 10.1117/12.2243405; Article number: 96842V; Conference: 8th International Symposium on Advanced Optical Manufacturing and Testing Technology: Optical Test, Measurement Technology, and Equipment, AOMATT 2016, April 26, 2016 - April 29, 2016; Sponsor: Chinese Academy of Sciences, Institute of Optics and Electronics (IOE); The Chinese Optical Society (COS);
Publisher: SPIEAuthor affiliation: 1 Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China2 Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai; 200083, China
Abstract: The increased sensitivity of space-based sensors has imposed greater stray light performance goals on telescope design. To meet the demand, a stray light test station for measuring point source transmission (PST) has been built with a lower threshold and higher accuracy. The station is nearly all black with dimensions of 28m long by 8m wide by 9m high. it is coupled with a double cylindrical chamber that reflects the specular light away from the instrument under test. The chamber is a Class 6 cleanroom. The station will allow measuring the instruments with up to a 1 meters diameter, and to perform these measurements at visible and infrared wavelengths. The instrument under test will allow to scan at azimuth angles ±110°, and at elevation ±15°. The tests were performed to estimate stray light characteristics of two optical instruments. Test results demonstrated PST performance below 1×10-7at visible wavelengths, and 1×10-6at infrared wavelengths. © 2016 SPIE. (4 refs.)Main Heading: Light transmissionControlled terms: Clean rooms - Laboratories - Manufacture - Optical testing - Stray lightUncontrolled terms: Cylindrical chambers - Infrared wavelengths - Point source transmission - Space optical system - Space-based sensors - Stray light performance - Telescope design - Visible wavelengthsClassification Code: 402.1 Industrial and Agricultural BuildingsIndustrial and Agricultural Buildings - 537.1 Heat Treatment ProcessesHeat Treatment Processes - 741.1 Light/OpticsLight/Optics - 741.3 Optical Devices and SystemsOptical Devices and Systems
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Development of wide field of view technology of synthetic aperture lidar
Li, Yi-Zhe1, 2; Xue, Bin2; Zhao, Yi-Yi2 Source: Guangxue Jingmi Gongcheng/Optics and Precision Engineering, v 24, p 300-308, October 1, 2016; Language: Chinese
; ISSN: 1004924X; DOI: 10.3788/OPE.20162413.0300;
Publisher: Chinese Academy of SciencesAuthor affiliation: 1 College of Materials Science and Opto-Electronic Technology, University of Chinese Academy of Sciences, Beijing; 101408, China2 Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China
Abstract: The development of Synthetic Aperture Ladar (SAL) both at domestic and abroad was reviewed, where the technical difficulties in its application and practice were introduced. Among these problems, the solutions to that of narrow field of view (FOV) were analyzed, demonstrating theoretical restriction in FOV of heterodyne detection in SAL. The endeavor and exploration of wide FOV SAL were summarized at home and abroad. Finally, the future development prospect of SAL was described and analyzed. © 2016, Science Press. All right reserved. (45 refs.)Main Heading: Synthetic aperturesControlled terms: Heterodyning - Optical radarUncontrolled terms: Development prospects - Field of views - Heterodyne detection - ITS applications - Laser ladar - Synthetic aperture ladar - Technical difficulties - Wide field of viewClassification Code: 716.2 Radar Systems and EquipmentRadar Systems and Equipment
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Surface ship target detection in hyperspectral images based on improved variance minimum algorithm
Wang, Zhengzhou1, 2, 3; Yin, Qinye2; Li, Hongguang3; Hu, Bingliang3 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 10033, 2016, Eighth International Conference on Digital Image Processing, ICDIP 2016
; ISSN: 0277786X, E-ISSN: 1996756X; ISBN-13: 9781510605039; DOI: 10.1117/12.2243872; Article number: 100330R; Conference: 8th International Conference on Digital Image Processing, ICDIP 2016, May 20, 2016 - May 23, 2016; Sponsor: Chengdu University of Information Technology; Chinese Academy of Sciences Chengdu Institute of Computer Applications; International Association of Computer Science and Information Technology; Sichuan Province Computer Federation;
Publisher: SPIEAuthor affiliation: 1 School of Electronic and Information Engineering, Xi'An Jiaotong University, Xi'an,Shanxi; 710049, China2 University of Chinese Academy of Sciences, Beijing; 100049, China3 Xi'An Institute of Optics and Precision Mechanics Chinese Academy of Science, Xi'an,Shanxi; 710119, China
Abstract: In order to realize the effective detection of surface structure targets in hyperspectral images, an improved target detection algorithm was proposed in this paper presents to solve the CEM algorithm problems which the large object extraction efficiency is low.First, the image was preprocessed, including end-member extraction, SAM classification. Second, after the ship pixels were subtracted from all pixels, the correlation matrix of pure background pixels was constructed to detect ship target. Third, the biggest write region was found as sea region by mathematical morphology. Finally, the false target pixels were removed from all target pixels using the characteristics which ship targets were surrounded in seawater, so the final ship targets were selected in the end. Experimental results show that the final max ratio between the energy of detection target and the energy of background increased greatly, the target signal is enhanced and the background signal is suppressed by the improved algorithm. © 2016 SPIE. (15 refs.)Main Heading: Image processingControlled terms: Computational electromagnetics - Extraction - Feature extraction - Independent component analysis - Mathematical morphology - Pixels - Radar target recognition - Ships - Spectroscopy - Target trackingUncontrolled terms: Background pixels - Background signals - Correlation matrix - Detection targets - Endmember extraction - Hyper-spectral images - Object extraction - Target detection algorithmClassification Code: 701 Electricity and MagnetismElectricity and Magnetism - 716.2 Radar Systems and EquipmentRadar Systems and Equipment - 802.3 Chemical OperationsChemical Operations
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Detecting densely distributed graph patterns for fine-grained image categorization
Zhang, Luming1; Yang, Yang2; Wang, Meng1; Hong, Richang1; Nie, Liqiang3; Li, Xuelong4 Source: IEEE Transactions on Image Processing, v 25, n 2, p 553-565, February 2016
; ISSN: 10577149; DOI: 10.1109/TIP.2015.2502147; Article number: 7331663;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 Department of Computer Science and Information Engineering, Hefei University of Technology, Hefei; 230009, China2 School of Computer Sciences and Engineering, University of Electronic Science and Technology of China, Chengdu; 610051, China3 School of Computing, National University of Singapore, Singapore; 119077, Singapore4 Center for OPTical IMagery Analysis and Learning, State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China
Abstract: Fine-grained image categorization is a challenging task aiming at distinguishing objects belonging to the same basiclevel category, e.g., leaf or mushroom. It is a useful technique that can be applied for species recognition, face verification, and so on. Most of the existing methods either have difficulties to detect discriminative object components automatically, or suffer from the limited amount of training data in each sub-category. To solve these problems, this paper proposes a new fine-grained image categorization model. The key is a dense graph mining algorithm that hierarchically localizes discriminative object parts in each image. More specifically, to mimic the human hierarchical perception mechanism, a superpixel pyramid is generated for each image. Thereby, graphlets from each layer are constructed to seamlessly capture object components. Intuitively, graphlets representative to each super-/sub-category is densely distributed in their feature space. Thus, a dense graph mining algorithm is developed to discover graphlets representative to each super-/ sub-category. Finally, the discovered graphlets from pairwise images are integrated into an image kernel for fine-grained recognition. Theoretically, the learned kernel can generalize several state-of-the-art image kernels. Experiments on nine image sets demonstrate the advantage of our method. Moreover, the discovered graphlets from each sub-category accurately capture those tiny discriminative object components, e.g., bird claws, heads, and bodies. © 2015 IEEE. (55 refs.)Main Heading: Image matchingControlled terms: Data mining - Imaging systemsUncontrolled terms: Dense graphs - Fine grained - Graphlet matching - Image kernel - Sub-categoryClassification Code: 723.2 Data Processing and Image ProcessingData Processing and Image Processing - 746 Imaging TechniquesImaging Techniques
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Investigation on high-efficient terahertz source based on two-color femtosecond laser-induced air plasma
Fan, Wen-Hui1; Chen, Ze-You1; Xie, Jun1; Chen, Xu1; Tang, Jie1; Zhao, Wei1 Source: Optics InfoBase Conference Papers, July 21, 2014, International Symposium on Ultrafast Phenomena and Terahertz Waves, ISUPTW 2016; ISBN-13: 9781943580217; DOI: 10.1364/ISUPTW.2016.IW3A.2; Conference: International Symposium on Ultrafast Phenomena and Terahertz Waves, ISUPTW 2016, October 10, 2016 - October 12, 2016; Sponsor: OSA - The Optical Society;
Publisher: OSA - The Optical SocietyAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China
Abstract: Terahertz radiation generated by two-color laser-induced air plasma has been investigated systematically. A highly efficient terahertz source has been achieved and can be utilized to carry out further investigation on terahertz sensing, spectroscopy, and imaging. © OSA 2016. (9 refs.)Main Heading: Terahertz wavesControlled terms: Laser produced plasmas - Terahertz spectroscopy - Ultrafast phenomenaUncontrolled terms: Air plasmas - High efficient - Terahertz radiation - Terahertz sensing - Terahertz sources - Two-color - Two-color laserClassification Code: 711 Electromagnetic WavesElectromagnetic Waves - 744.9 Laser ApplicationsLaser Applications - 931.1 MechanicsMechanics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


A target detection method for hyperspectral image based on mixture noise model
Zheng, Xiangtao1, 2; Yuan, Yuan1; Lu, Xiaoqiang1 Source: Neurocomputing, v 216, p 331-341, December 5, 2016
; ISSN: 09252312, E-ISSN: 18728286; DOI: 10.1016/j.neucom.2016.08.015;
Publisher: Elsevier B.V.Author affiliation: 1 Center for OPTical IMagery Analysis and Learning (OPTIMAL), State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Shaanxi, Xi'an; 710119, China2 University of the Chinese Academy of Sciences, 19A Yuquanlu, Beijing; 100049, China
Abstract: Subpixel hyperspectral detection is a kind of method which tries to locate targets in a hyperspectral image when the spectrum of the targets is given. Due to its subpixel nature, targets are often smaller than one pixel, which increases the difficulty of detection. Many algorithms have been proposed to tackle this problem, most of which model the noise in all spatial points of hyperspectral image by multivariate normal distribution. However, this model alone may not be an appropriate description of the noise distribution in hyperspectral image. After carefully studying the distribution of hyperspectral image, it is concluded that the gradient of noise also obeys normal distribution. In this paper two detectors are proposed: mixture gradient structured detector (MGSD) and mixture gradient unstructured detector (MGUD). These detectors are based on a new model which takes advantage of the distribution of the gradient of the noise. This makes the detectors more accordant with the practical situation. To evaluate the performance of the proposed detectors, three different data sets, including one synthesized data set and two real-world data sets, are used in the experiments. Results show that the proposed detectors have better performance than current subpixel detectors. © 2016 Elsevier B.V. (53 refs.)Main Heading: Radar target recognitionControlled terms: Mixtures - Normal distribution - Pixels - Spectroscopy - Target tracking - Virtual realityUncontrolled terms: Hyper-spectral images - Hyperspectral Data - Hyperspectral detections - Mixture noise - Multi-variate normal distributions - Noise distribution - Spatial points - Sub pixels
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Spectral multimodal hashing and its application to multimedia retrieval
Zhen, Yi1; Gao, Yue2; Yeung, Dit-Yan3; Zha, Hongyuan1; Li, Xuelong4 Source: IEEE Transactions on Cybernetics, v 46, n 1, p 27-38, January 2016
; ISSN: 21682267; DOI: 10.1109/TCYB.2015.2392052; Article number: 7163570;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 College of Computing, Georgia Institute of Technology, Atlanta; GA, United States2 Tsinghua National Laboratory for Information Science and Technology, Department of Automation, Tsinghua University, Beijing, China3 Department of Computer Science and Engineering, Hong Kong University of Science and Technology, Hong Kong, Hong Kong4 Center for Optical Imagery Analysis and Learning, State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, China
Abstract: In recent years, multimedia retrieval has sparked much research interest in the multimedia, pattern recognition, and data mining communities. Although some attempts have been made along this direction, performing fast multimodal search at very large scale still remains a major challenge in the area. While hashing-based methods have recently achieved promising successes in speeding-up large-scale similarity search, most existing methods are only designed for uni-modal data, making them unsuitable for multimodal multimedia retrieval. In this paper, we propose a new hashing-based method for fast multimodal multimedia retrieval. The method is based on spectral analysis of the correlation matrix of different modalities. We also develop an efficient algorithm that learns some parameters from the data distribution for obtaining the binary codes. We empirically compare our method with some state-of-the-art methods on two real-world multimedia data sets. © 2015 IEEE. (57 refs.)Main Heading: Pattern recognitionControlled terms: Algorithms - Data mining - Modal analysis - Spectrum analysisUncontrolled terms: Correlation matrix - Data distribution - Data mining community - Multimedia Retrieval - Multimodal search - Research interests - Scale similarity - State-of-the-art methods
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


High-Order Energies for Stereo Segmentation
Peng, Jianteng1; Shen, Jianbing1; Li, Xuelong2 Source: IEEE Transactions on Cybernetics, v 46, n 7, p 1616-1627, July 2016
; ISSN: 21682267; DOI: 10.1109/TCYB.2015.2453091; Article number: 7164318;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 Beijing Laboratory of Intelligent Information Technology, School of Computer Science, Beijing Institute of Technology, Beijing; 100081, China2 Center for OPTical IMagery Analysis and Learning (OPTIMAL), State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China
Abstract: In this paper, we propose a novel segmentation approach for stereo images using the high-order energy optimization, which utilizes the disparity maps and statistical information of stereo images to enrich the high-order potential functions. To the best of our knowledge, our approach is the first one to formulate the problem of stereo segmentation as a high-order energy optimization problem, which simultaneously segments the foreground objects in left and right images using the proposed high-order potential function. A new method for designing the penalty function in our high-order term is proposed by the corresponding pixels and their neighboring pixels between left and right images. The relationships of stereo correspondence by disparity maps are further employed to enhance the connections between the left and right stereo images. Experimental results demonstrate that the proposed approach can effectively improve the performance of two kinds of stereo segmentation, including the automatic saliency-aware stereocut and the interactive stereo segmentation with user scribbles. © 2015 IEEE. (41 refs.)Main Heading: Stereo image processingControlled terms: Image segmentation - Optimization - PixelsUncontrolled terms: Disparity map - Foreground objects - High-order - High-order potentials - Penalty function - Statistical information - Stereo correspondences - Stereo-image
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Multi-channel terahertz wavelength division demultiplexer with defects-coupled photonic crystal waveguide
Li, Shaopeng1; Liu, Hongjun1; Sun, Qibing1; Huang, Nan1 Source: Journal of Modern Optics, v 63, n 10, p 955-960, May 30, 2016
; ISSN: 09500340, E-ISSN: 13623044; DOI: 10.1080/09500340.2015.1111457;
Publisher: Taylor and Francis Ltd.Author affiliation: 1 State Key Laboratory of Transient Optics and Photonics Technology, Xian Institute of Optics and Precision Mechanics, Chinese Academy of Science (CAS), Xian, China
Abstract: Terahertz (THz) wavelength division demultiplexer based on a compact defects-coupled photonic crystal waveguide is proposed and demonstrated numerically. This device consists of an input waveguide that perpendicularly coupled with a series of defects cavities, each of which captures the resonance frequency from the input waveguide. Coupled-mode theory and finite element method are used to analyze the transmission properties of the structure. It is found that the transmission wavelength centered around 1 THz can be adjusted by changing the geometrical parameters of defects cavities, which equals to THz waves generated by optical methods such as difference frequency generation and optical rectification. Applications in this frequency range are urgently needed. Furthermore, the highest transmission efficiency of 0.94 can be achieved when a perfect wavelength-selective mirror is set in the output waveguide. © 2015 Taylor & Francis. (27 refs.)Main Heading: Optical waveguidesControlled terms: Crystal defects - Defects - Demultiplexing - Finite element method - Geometry - Optical frequency conversion - Photonic crystals - Terahertz waves - Waveguide components - WaveguidesUncontrolled terms: Demultiplexers - Difference-frequency generation - Optical rectifications - Photonic crystal waveguide - Resonance frequencies - Tera Hertz - Transmission efficiency - Transmission wavelength
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Ultrafast laser photoinscription of large-mode-area waveguiding structures in bulk dielectrics
Stoian, R.1; D'Amico, C.1; Bhuyan, M.K.1; Cheng, G.1, 2 Source: Optics and Laser Technology, v 80, p 98-103, June 2016
; ISSN: 00303992; DOI: 10.1016/j.optlastec.2015.11.025;
Publisher: Elsevier LtdAuthor affiliation: 1 Laboratoire Hubert Curien, Université de Lyon, Université Jean Monnet, UMR, CNRS 5516, Saint Etienne, France2 State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics, CAS, Xi'an, Shaanxi, China
Abstract: Ultrafast laser photoinscription and laser-based refractive index engineering develop towards a unique way for three-dimensional optical design inside bulk materials for the conception of embedded photonic applications. The specific optical functions for the light guiding elements, notably their single mode characteristics and the accessible spectral domains, depend on the achieved refractive index contrast in the material transparency window and on the characteristic dimensions of the optical modification. We give here an overview of several laser processing options, developed to increase the effective index area and contrast using pulse engineering methods in space and time, and optical design involving focal shaping, tubular concepts, evanescently coupled waveguide arrays, or structured waveguides. © 2015 Elsevier Ltd. Allrightsreserved. (64 refs.)Main Heading: Optical pulse shapingControlled terms: Optical design - Optical waveguides - Pulse shaping - Refractive index - Ultrafast lasers - WaveguidesUncontrolled terms: Coupled waveguides - Engineering methods - Large mode area - Optical modifications - Photoinscription - Photonic application - Spectral domains - Waveguiding structuresClassification Code: 713.4 Pulse CircuitsPulse Circuits - 714.3 WaveguidesWaveguides - 741.1 Light/OpticsLight/Optics - 744.1 Lasers, GeneralLasers, General
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


SERS activity with tenfold detection limit optimization on a type of nanoporous AAO-based complex multilayer substrate
Sui, Chaofan1, 2; Wang, Kaige1, 2; Wang, Shuang1, 2; Ren, Junying1; Bai, Xiaohong3; Bai, Jintao1, 2 Source: Nanoscale, v 8, n 11, p 5920-5927, March 21, 2016
; ISSN: 20403364, E-ISSN: 20403372; DOI: 10.1039/c5nr06771e;
Publisher: Royal Society of ChemistryAuthor affiliation: 1 National Key Laboratory Base of Photoelectric Technology, Functional Materials Co-Sponsored by Province and Ministry, Institute of Photonics Photon-Technology, Northwest University, Xi'an, China2 International Technology Cooperation Base of Photoelectric Technology, Functional Materials of Ministry of Science and Technology, Northwest University, Xi'an, China3 Xi'An Institute of Optics and Precision Mechanics Chinese Academy of Science, Key Laboratory of Ultrafast Photoelectric Dignostic Technology, Xi'an, China
Abstract: Most of SERS applications are constricted by heterogeneous hotspots and aggregates of nanostructure, which result in low sensitivity and poor reproducibility of characteristic signals. This work intends to introduce SERS properties of a type of SERS-active substrate, Au-CuCl2-AAO, which is innovatively developed on a porous anodic alumina oxide (AAO) template. Spectral measuring results of Rhodamine 6G (R6G) on this substrate optimized by controlling morphology and gold thickness showed that enhancement factor (2.30 × 107) and detection limit (10-10M) were both improved and represented better performance than its template AAO. Homogenous hot spots across the region of interest were achieved by scanning SERS intensity distribution for the band at 1505 cm-1in 5 × 5 μm2area. Furthermore, the promising SERS activity of the flower-patterned substrate was theoretically explained through simulation of the electromagnetic field distribution. In addition, this SERS substrate is proposed for applications within the field of chemical and biochemical analyses. © 2016 The Royal Society of Chemistry. (47 refs.)Main Heading: SubstratesControlled terms: Alumina - Anodic oxidation - Chemical analysis - Electromagnetic fields - Image segmentationUncontrolled terms: Biochemical analysis - Characteristic signal - Electromagnetic field distribution - Intensity distribution - Multilayer substrate - Patterned substrates - Porous anodic alumina - SERS-active substratesClassification Code: 539.2.1 Protection MethodsProtection Methods - 701 Electricity and MagnetismElectricity and Magnetism - 804.2 Inorganic CompoundsInorganic Compounds
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Holographic optical trapping and manipulation based on phase-only liquid-crystal spatial light modulator
Liang, Yansheng1; Yao, Baoli1; Ma, Baiheng1; Lei, Ming1; Yan, Shaohui1; Yu, Xianghua1 Source: Guangxue Xuebao/Acta Optica Sinica, v 36, n 3, March 10, 2016; Language: Chinese
; ISSN: 02532239; DOI: 10.3788/AOS201636.0309001; Article number: 0309001;
Publisher: Chinese Optical SocietyAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; Shaanxi, China
Abstract: An improved and rapid three dimensional Gerchberg-Saxton (GS) algorithm based on the classic GS algorithm for computer generated holograms is proposed and applied to holographic optical tweezers. Theoretical simulations and experimental results have demonstrated the rapidity and efficiency of the proposed algorithm. A robust holographic optical tweezers setup based on phase-only liquid-crystal spatial light modulator(SLM) is built, and stable trapping and dynamic manipulation of yeast cells and silica beads with large array traps in three dimensions are demonstrated. Two special traps, i.e., line trap with intensity gradient distribution and optical vortex trap, are generated to transport and rotate micro-particles respectively. The system is verified to be robust on particles manipulations, which provides a new and powerful tool for researches on biology, colloid physics and so on. © 2016, Chinese Laser Press. All right reserved. (31 refs.)Main Heading: Light modulatorsControlled terms: Algorithms - Computer generated holography - Holograms - Holography - Light modulation - Liquid crystals - Molecular biology - Optical tweezersUncontrolled terms: Computer generated holograms - G-S algorithms - Holographic optical tweezers - Intensity gradients - Liquid crystal spatial light modulators - Optical trapping and manipulation - Opticaltrapping - Theoretical simulationClassification Code: 461.9 BiologyBiology - 741.1 Light/OpticsLight/Optics - 743 HolographyHolography - 743.1 Holographic TechniquesHolographic Techniques - 744.9 Laser ApplicationsLaser Applications
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Compressed sensing sparse reconstruction for coherent field imaging
Cao, Bei1; Luo, Xiu-Juan1; Zhang, Yu1; Liu, Hui1; Chen, Ming-Lai1 Source: Chinese Physics B, v 25, n 4, April 1, 2016
; ISSN: 16741056; DOI: 10.1088/1674-1056/25/4/040701; Article number: 040701;
Publisher: Institute of Physics PublishingAuthor affiliation: 1 Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, China
Abstract: Return signal processing and reconstruction plays a pivotal role in coherent field imaging, having a significant influence on the quality of the reconstructed image. To reduce the required samples and accelerate the sampling process, we propose a genuine sparse reconstruction scheme based on compressed sensing theory. By analyzing the sparsity of the received signal in the Fourier spectrum domain, we accomplish an effective random projection and then reconstruct the return signal from as little as 10% of traditional samples, finally acquiring the target image precisely. The results of the numerical simulations and practical experiments verify the correctness of the proposed method, providing an efficient processing approach for imaging fast-moving targets in the future. © 2016 Chinese Physical Society and IOP Publishing Ltd. (16 refs.)Main Heading: Image processingControlled terms: Compressed sensing - Computation theory - Image reconstruction - Numerical methods - Signal processing - Signal reconstructionUncontrolled terms: Coherent fields - Computational imaging - Processing approach - Random projections - Received signals - Reconstructed image - Sampling process - Sparse reconstructionClassification Code: 716.1 Information Theory and Signal ProcessingInformation Theory and Signal Processing - 721.1 Computer Theory, Includes Formal Logic, Automata Theory, Switching Theory, Programming TheoryComputer Theory, Includes Formal Logic, Automata Theory, Switching Theory, Programming Theory - 921.6 Numerical MethodsNumerical Methods
Database: Compendex
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Quasi-all-fiber high-efficiency divided chirp-pulse amplification system based on active controlling
Yu, J.1, 2; Feng, Y.1, 2, 3; Duan, L.N.1, 2; Li, X.H.4; Hu, X.H.1, 2; Zhang, T.1; Zhang, W.1; Wang, Y.S.1; Yang, Z.1; Zhao, W.1 Source: IEEE Photonics Journal, v 8, n 1, February 2016
; ISSN: 19430655; DOI: 10.1109/JPHOT.2016.2524201; Article number: 7397866;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xian Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xian, China2 University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, China3 Department of Physics, Xian Jiaotong University, Xian, China4 School of Physics and Information Technology, Shaanxi Normal University, Xian, China
Abstract: We present a new high-efficiency divided chirp-pulse amplification (DCPA) system based on an actively controlled quasi-all-fiber structure. As a proof-of-principle experiment, a two-channel amplification system composed of single-mode ytterbium-doped fiber is constructed. The experimental results show that the degree of linear polarization of ∼93% is maintained after recombination and the system efficiency is up to ∼95%. In addition, the beam quality (M2factor) is around 1.2. Moreover, the system can operate stably for a long time without performance degradation. Compared with the traditional spatial DCPA, this system exhibits some advantages, such as improved spatial adjustment, high stability, compact size, and low cost. It is demonstrated that this work paves the way to design a quasi-all-fiber high-performance pulsed laser system. © 2009-2012 IEEE. (19 refs.)Main Heading: Pulsed lasersControlled terms: Amplification - Chirp modulation - Efficiency - Fibers - Laser beams - Ultrafast lasersUncontrolled terms: Chirp pulse amplification system - Chirp pulse amplifications - Degree of linear polarization - Fiber optics systems - Laser beam combining - Performance degradation - Proof-of-principle experiments - Ytterbium doped fibersClassification Code: 716 Telecommunication; Radar, Radio and TelevisionTelecommunication; Radar, Radio and Television - 744.1 Lasers, GeneralLasers, General - 744.8 Laser Beam InteractionsLaser Beam Interactions - 913.1 Production EngineeringProduction Engineering
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


A method of removing reflected highlight on images based on polarimetric imaging
Yang, Fanchao1, 2; Tang, Xingjia1; Hu, Bingliang1; Wei, Ruyi1; Kong, Liang1; Li, Yong1 Source: Journal of Sensors, v 2016, 2016
; ISSN: 1687725X, E-ISSN: 16877268; DOI: 10.1155/2016/9537320; Article number: 9537320;
Publisher: Hindawi Publishing CorporationAuthor affiliation: 1 Key Laboratory of Spectral Imaging Technology, Xi'An Institute of Optics and Precision Mechanic, Chinese Academy of Sciences, Xi'an; 710119, China2 University of Chinese Academy of Sciences, Beijing; 10049, China
Abstract: A method of removing reflected highlight is proposed on polarimetric imaging. Polarization images (0°, 45°, 90°, and 135°) and the reflection angle are required in this reflected light removal algorithm. This method is based on the physical model of reflection and refraction, and no additional image processing algorithm is necessary in this algorithm. Compared to traditional polarization method with single polarizer, restricted observation angle of Brewster is not demanded and multiple reflection areas of different polarization orientations can be removed simultaneously. Experimental results, respectively, demonstrate the features of this reflected light removal algorithm, and it can be considered very suitable in polarization remote sensing. © 2016 Fanchao Yang et al. (13 refs.)Main Heading: PolarizationControlled terms: Algorithms - Image processing - Polarimeters - Remote sensingUncontrolled terms: Image processing algorithm - Multiple reflections - Polarimetric imaging - Polarization images - Polarization method - Polarization orientation - Reflection and refractions - Removal algorithmsClassification Code: 941.3 Optical InstrumentsOptical Instruments
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


High-speed, high-voltage pulse generation using avalanche transistor
Yong-Sheng, Gou1, 2; Bai-Yu, Liu1; Yong-Lin, Bai1; Jun-Jun, Qin1; Xiao-Hong, Bai1; Bo, Wang1; Bing-Li, Zhu1; Chuan-Dong, Sun1 Source: Review of Scientific Instruments, v 87, n 5, May 1, 2016
; ISSN: 00346748, E-ISSN: 10897623; DOI: 10.1063/1.4948727; Article number: 054708;
Publisher: American Institute of Physics Inc.Author affiliation: 1 Ultra-fast Diagnostic Labs, Xi'An Institute of Optics and Precision Mechanics, Xi'an; 710119, China2 University of Chinese Academy of Sciences, Beijing; 100049, China
Abstract: In this work, the conduction mechanism of avalanche transistors was demonstrated and the operation condition for generating high-speed pulse using avalanche transistors was illustrated. Based on the above analysis, a high-speed and high-voltage pulse (HHP) generating circuit using avalanche transistors was designed, and its working principle and process were studied. To improve the speed of the output pulse, an approach of reducing the rise time of the leading edge is proposed. Methods for selecting avalanche transistor and reducing the parasitic inductance and capacitance of printed circuit board (PCB) were demonstrated. With these instructions, a PCB with a tapered transmission line was carefully designed and manufactured. Output pulse with amplitude of 2 kV and rise time of about 200 ps was realized with this PCB mounted with avalanche transistors FMMT417, indicating the effectiveness of the HHP generating circuit design. © 2016 Author(s). (11 refs.)Main Heading: Pulse generatorsControlled terms: Capacitance - Electric potential - Integrated circuit manufacture - Power transistors - Printed circuit boards - Printed circuits - Reconfigurable hardware - TransistorsUncontrolled terms: Avalanche transistors - Conduction Mechanism - High voltage pulse - High voltage pulse generation - Operation conditions - Parasitic inductances - Printed circuit boards (PCB) - Tapered transmission linesClassification Code: 701.1 Electricity: Basic Concepts and PhenomenaElectricity: Basic Concepts and Phenomena - 713.4 Pulse CircuitsPulse Circuits - 714.2 Semiconductor Devices and Integrated CircuitsSemiconductor Devices and Integrated Circuits - 721.3 Computer CircuitsComputer Circuits
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Far-field focal spot measurement of 10kJ-level laser facility
Wang, Zheng-Zhou1, 3, 4; Xia, Yan-Wen2; Li, Hong-Guang4; Hu, Bing-Liang4; Yin, Qin-Ye1; Zheng, Kui-Xing2 Source: Guangzi Xuebao/Acta Photonica Sinica, v 45, n 8, August 1, 2016; Language: Chinese
; ISSN: 10044213; DOI: 10.3788/gzxb20164508.0812001; Article number: 0812001;
Publisher: Chinese Optical SocietyAuthor affiliation: 1 School of Electronic & Information Engineering, Xi'an Jiaotong University, Xi'an; 710049, China2 Research Center of Laser Fusion, China Academy of Engineering Physics, Mianyang; Sichuan; 621900, China3 University of Chinese Academy of Sciences, Beijing; 100039, China4 Xi'an Institute of Optics and Precision Mechanics of Chinese Academy of Science, Xi'an; 710119, China
Abstract: In order to evaluate the far-field beam quality of 10 kJ-level laser facility with different off-axis wedged focus lens, by utilizing the methods of the sampling of weak light beams and amplification imaging of splitting beams, the focal spot data of 3ω laser was collected by two 16-bit scientific-grade CCD cameras in the paths of main lobe and side lobe under the conditions of that the lateral magnification coefficient is the same but the intensity attenuation coefficient is different. One CCD obtained main lobe of far-field image, the other acquired its side lobe. The far-field focal spot was reconstructed based on the mathematical model of schlieren method, and the dynamic range is 1 151.7∶1. The influence of CCD dynamic range, relative magnification ratio and system noise on reconstructed image was analyzed. Experimental results show that, the method can achieve a high dynamic range far-field accurate measurement of focal spot, the stitching error is less than one pixel, which meets the requirements of targeting experiments in experimental precision. © 2016, Science Press. All right reserved. (14 refs.)Main Heading: CCD camerasControlled terms: High power lasers - Optical beam splitters - Optical data processingUncontrolled terms: Attenuation coefficient - Dynamic range - Experimental precision - Far field - Far-field focal spots - Focal spot - Lateral magnification - Optical measurementClassification Code: 714.2 Semiconductor Devices and Integrated CircuitsSemiconductor Devices and Integrated Circuits - 723.2 Data Processing and Image ProcessingData Processing and Image Processing - 741.3 Optical Devices and SystemsOptical Devices and Systems - 744.1 Lasers, GeneralLasers, General
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Regularized Taylor Echo State Networks for Predictive Control of Partially Observed Systems
Xiang, Kui1; Li, Bing Nan2; Zhang, Liyan1; Pang, Muye1; Wang, Meng3; Li, Xuelong4 Source: IEEE Access, v 4, p 3300-3309, 2016; E-ISSN: 21693536; DOI: 10.1109/ACCESS.2016.2582478; Article number: 7494924;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 School of Automation, Wuhan University of Technology, Wuhan; 430070, China2 School of Instrument Science, Hefei University of Technology, Hefei; 230009, China3 School of Computer and Information, Hefei University of Technology, Hefei; 230009, China4 State Key Laboratory of Transient Optics and Photonics, Center for Optical Imagery Analysis and Learning, Xi'An Institute of Optics and Precision Mechanics, Xi'an; 710119, China
Abstract: The existing neural networks suffer from partial observation while modeling and controlling dynamic systems. In this paper, a new linearized recurrent neural network, the Taylor expanded echo state network (TESN), is proposed for predictive control of partially observed dynamic systems. Two schemes of regularization, ridge regression and sparse regression, are imposed on TESNs to tackle the issue of ill-conditioned estimation. Furthermore, two estimators, lasso and elastic net, are investigated for sparse regression. Regularized learning is found to improve the estimation consistency of readout coefficients and, at the same time, suppress the accumulation of linearization residues in a prediction horizon. A series of experiments was carried out, and the results verified that regularized learning is contributive to TESNs in predictive control of partially observed dynamic systems. © 2016 IEEE. (31 refs.)Main Heading: Regression analysisControlled terms: Linearization - Neural networks - Recurrent neural networksUncontrolled terms: Echo state networks - Observed systems - Partial observation - Prediction horizon - Predictive control - Ridge regression - Sparse regression - Sparse regularizationsClassification Code: 922.2 Mathematical StatisticsMathematical Statistics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


A review of large aperture Schlieren photography technique
Xu, Song-Bo1; Xie, Yong-Jun1; Chen, Lei2 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 9796, 2016, Selected Papers of the Photoelectronic Technology Committee Conferences held November 2015
; ISSN: 0277786X, E-ISSN: 1996756X; ISBN-13: 9781628418811; DOI: 10.1117/12.2230137; Article number: 97960G; Conference: International Symposia on Atmosphere Optics and Adaptive Optics, Testing and Driving of Laser Fusion Energy Technology, High-performance Special Optical Film Technology, Novel Navigation Technology, Monitoring, Early Warning, Removal Technology of Space Targets and Debris, and UAV Payload Technology, November 15, 2015 - November 28, 2015; Sponsor: Chinese Academy of Engineering; Chinese Society for Optical Engineering; National Natural Science Foundation of China;
Publisher: SPIEAuthor affiliation: 1 Xi'an Institute of Optics and Precision Mechanics, CAS, Xi'an; 710119, China2 China Aerodynamics Research and Development Center, Mianyang; 621000, China
Abstract: Schlieren photography is a visual process to display the flow of fluids of varying density. It is widely used in wind tunnel tests to photograph the flow of air around objects. To achieve schlieren images with high sensitivity and high resolution, and satisfy the requirements of the large-scale wind tunnel tests, it is urgent to develop schlieren photographers with large aperture primary mirrors. However, the application of large aperture primary mirrors may bring many challenges in the design of the schlieren system. First, the surface figure of large aperture primary mirrors is difficult to control so that the support structure may need more strategical design. Second, because the schlieren system works under some severe environments of the wind tunnel test including the air disturbance, wind-induced ground vibration and high ambient pressure, it has to withstand serious instability risks to ensure a good schlieren image quality. In this work, the current status of the development in the large aperture schlieren systems is reviewed. Several advanced methods, for example, active damping control technique, focal spot monitoring technique, 18-points whilffletree support technique, etc., are introduced to deal with the challenges of the large aperture schlieren system. This work aims at improving the technical development of large aperture schlieren photographer, which may contribute to the acquisition of the high sensitive and high resolution schlieren images and the improvement of the testing capability in wind tunnel experiments. © 2016 SPIE. (20 refs.)Main Heading: Schlieren systemsControlled terms: Adaptive optics - Mirrors - Optical testing - Photography - Space debris - Wind stress - Wind tunnelsUncontrolled terms: Active damping controls - Image stabilization - Monitoring techniques - Primary mirrors - Schlieren - Schlieren photography - Technical development - Wind tunnel experimentClassification Code: 443.1 Atmospheric PropertiesAtmospheric Properties - 651.2 Wind TunnelsWind Tunnels - 656.1 Space FlightSpace Flight - 741.1 Light/OpticsLight/Optics - 741.3 Optical Devices and SystemsOptical Devices and Systems - 742.2 Photographic EquipmentPhotographic Equipment - 746 Imaging TechniquesImaging Techniques
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


3D object hiding using three-dimensional ptychography
Zhang, Jun1; Wang, Zhibo2; Li, Tuo1; Pan, An4; Wang, Yali1, 3; Shi, Yishi1, 3 Source: Journal of Optics (United Kingdom), v 18, n 9, September 2016
; ISSN: 20408978, E-ISSN: 20408986; DOI: 10.1088/2040-8978/18/9/095701; Article number: 095701;
Publisher: Institute of Physics PublishingAuthor affiliation: 1 College of Material Science and Opto-Electronic Technology, University of Chinese Academy of Sciences, Beijing; 100049, China2 School of Electronic, Electrical and Communication Engineering, University of Chinese Academy of Sciences, Beijing; 100049, China3 Academy of Opto-Electronics, Chinese Academy of Sciences, Beijing; 100094, China4 Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China
Abstract: We present a novel technique for 3D object hiding by applying three-dimensional ptychography. Compared with 3D information hiding based on holography, the proposed ptychography-based hiding technique is easier to implement, because the reference beam and high-precision interferometric optical setup are not required. The acquisition of the 3D object and the ptychographic encoding process are performed optically. Owing to the introduction of probe keys, the security of the ptychography-based hiding system is significantly enhanced. A series of experiments and simulations demonstrate the feasibility and imperceptibility of the proposed method. © 2016 IOP Publishing Ltd. (34 refs.)Main Heading: Security of dataControlled terms: Fourier optics - OpticsUncontrolled terms: 3D information - Encoding process - High-precision - Novel techniques - optical hiding - Optical information security - Optical set-up - Reference beamsClassification Code: 723.2 Data Processing and Image ProcessingData Processing and Image Processing - 741.1 Light/OpticsLight/Optics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


A compact QCW conduction-cooled high power semiconductor laser array
Zhu, Qiwen1, 2; Zhang, Pu1; Wang, Shuna1; Wu, Dihai1; Nie, Zhiqiang1; Xiong, Lingling1; Song, Yunfei1; Liu, Xingsheng1, 3 Source: 2016 17th International Conference on Electronic Packaging Technology, ICEPT 2016, p 227-233, October 4, 2016, 2016 17th International Conference on Electronic Packaging Technology, ICEPT 2016; ISBN-13: 9781509013968; DOI: 10.1109/ICEPT.2016.7583125; Article number: 7583125; Conference: 17th International Conference on Electronic Packaging Technology, ICEPT 2016, August 16, 2016 - August 19, 2016;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Shanxi; 710119, China2 University of Chinese Academy of Sciences, Beijing, China3 Focuslight Technologies Co. LTD, Xi'An Hi-Tech Industrial Development Zone, No. 60 Xibu Road, New Industrial Park, Xi'an, Shanxi; 710119, China
Abstract: With the improvement of performance and reliability, high power semiconductor lasers have been widely applied in more and more fields. Thermal management is one of the most important issues effecting the optical-electrical performance of high power semiconductor laser. Compared with liquid-cooled techniques, conduction-cooled techniques have many advantages in some special applications because it could be adaptable for extreme environments, such as high temperature and low temperature. In this paper, a compact quasi-continuous wave (QCW) conduction-cooled high power semiconductor laser array was studied. The thermal behavior of the conduction-cooled semiconductor laser array with different structure and operation parameters were carried out using finite element method (FEM). The structure parameters of G-Stack semiconductor laser array was presented and optimized. Finally, A high power semiconductor laser array with superior performance was fabricated and characterized. © 2016 IEEE. (9 refs.)Main Heading: Semiconductor lasersControlled terms: Chip scale packages - Electronics packaging - Finite element method - High power lasers - High temperature applications - TemperatureUncontrolled terms: Conduction cooled - High power - Quasi-continuous waves - Semiconductor laser arrays - Thermal optimizationClassification Code: 641.1 ThermodynamicsThermodynamics - 714.2 Semiconductor Devices and Integrated CircuitsSemiconductor Devices and Integrated Circuits - 744.1 Lasers, GeneralLasers, General - 744.4.1 Semiconductor LasersSemiconductor Lasers - 921.6 Numerical MethodsNumerical Methods
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Vibration response analysis of lightweight INS and optimization of vibration absorber
Wang, Ping1; Zhang, Guangpeng1; Wei, Fei2; Zhang, Yanshun3; Xie, Fangfang1 Source: Yi Qi Yi Biao Xue Bao/Chinese Journal of Scientific Instrument, v 37, n 8, p 1898-1905, August 1, 2016; Language: Chinese
; ISSN: 02543087;
Publisher: Science PressAuthor affiliation: 1 School of Mechanical and Precision Instrument Engineering, Xi'an University of Technology, Xi'an; 710048, China2 The 54th Research Institute of China Electronics Technology Group Corporation, Shijiazhuang; 050081, China3 School of Instrument Science and Opto-electronics Engineering, Beihang University, Beijing; 100191, China
Abstract: The structure flexibility caused by lightweight design of inertial navigation system (INS) will generate a non-negligible influence on the vibration response of INS. Aiming at a certain lightweight inertial navigation structure, the dynamic model of the INS is established through adopting the substructure synthesis method based on frequency response functions. Subsequently, the influence of IMU flexibility on the INS is analyzed using this model. In addition, a parameter optimization design method of the vibration absorbing system is proposed. Through the optimization of the vibration absorber, the angular displacement of the INS decreases obviously, and the vibration coupling is suppressed effectively. Finally, the accuracy of the proposed optimization method is verified by vibration experiment, and it is also found that the heading and attitude measurement precision of the INS in the vibration process is improved after the optimization of the vibration absorber parameters. © 2016, Science Press. All right reserved. (18 refs.)Main Heading: Vibration analysisControlled terms: Air navigation - Frequency response - Inertial navigation systems - Navigation - Navigation systems - Structural designUncontrolled terms: Flexibility - Inertial navigation systems (INS) - Lightweight - Substructure - Vibration absorberClassification Code: 408.1 Structural Design, GeneralStructural Design, General - 431.5 Air Navigation and Traffic ControlAir Navigation and Traffic Control
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Transmission volume phase holographic gratings in photo-thermo-refractive glass written with femtosecond laser Bessel beams
Zhang, Y.J.1, 2; Zhang, G.D.2; Chen, C.L.1; Stoian, R.3; Cheng, G.H.2 Source: Optical Materials Express, v 6, n 11, p 3491-3499, 2016; E-ISSN: 21593930; DOI: 10.1364/OME.6.003491;
Publisher: OSA - The Optical SocietyAuthor affiliation: 1 Shaanxi Key Laboratory for Condensed Matter Structure and Properties, Northwestern Polytechnical University, Xi'an; 710129, China2 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics of CAS, Xi'an; 710119, China3 Laboratoire Hubert Curien, UMR 5516 CNRS, Université de Lyon, Université Jean Monnet, Saint Etienne; 42000, France
Abstract: Transmission volume phase holographic gratings were fabricated in bulk photothermo- refractive glass using zero-order femtosecond laser Bessel beams and subsequent thermal treatment. Microstructures composed of nano-sized crystals were observed in the exposed regions. The concentration of nano-crystals depended on the writing power, but the size of the nano-crystals was found to be quasi power-independent. Low writing power led to sparse nano-crystals, while optimized writing power achieved dense nano-crystals distribution and high refractive index change. Effects of the gratings thickness, writing laser power and thermal treatment on the diffraction efficiency were investigated. A maximum diffraction efficiency of 94.73% was achieved (at 532 nm testing wavelength) with 1 mm grating thickness at period of 5 μm. © 2016 Optical Society of America. (27 refs.)Main Heading: Diffraction gratingsControlled terms: Bessel functions - Diffraction - Diffraction efficiency - Efficiency - Glass - Heat treatment - Holographic gratings - Holography - Laser beams - Refractive index - Ultrashort pulsesUncontrolled terms: Bessel beam - High refractive index - Laser power - Nano-sized crystals - Photo-thermo-refractive glass - Quasi-power - Transmission volume phase holographic gratings - Writing powerClassification Code: 537.1 Heat Treatment ProcessesHeat Treatment Processes - 741.1 Light/OpticsLight/Optics - 741.3 Optical Devices and SystemsOptical Devices and Systems - 743 HolographyHolography - 744.8 Laser Beam InteractionsLaser Beam Interactions - 746 Imaging TechniquesImaging Techniques - 812.3 GlassGlass - 913.1 Production EngineeringProduction Engineering - 921 MathematicsMathematics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Integrated measurement system with galileo telescope combined with cylindrical lens
Liu, Ai-Min1, 2; Gao, Li-Min1; Xiao, Mao-Sen1; Lu, Wei-Guo1; Wang, Hai-Xia1 Source: Guangzi Xuebao/Acta Photonica Sinica, v 45, n 11, November 1, 2016; Language: Chinese
; ISSN: 10044213; DOI: 10.3788/gzxb20164511.1112002; Article number: 1112002;
Publisher: Chinese Optical SocietyAuthor affiliation: 1 Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China2 University of Chinese Academy of Sciences, Beijing; 100039, China
Abstract: To achieve azimuth and height measurement of a slowly moving point in a certain distance and wide field of view, a combined long-focal-length cylindrical lens measurement system was built. A point shape reticle, a long-focal-length optical system formed by a Galileo telescope combined with cylindrical lens and two orthogonal linear array CCD were utilized. There isn't a real middle image plane in the combined long-focal-length optical system with a relatively short optical length. The front part of the system is a Galileo telescope, and its focal power is approximate to 0. Within a measurement range, some parameters, such as the value of the angular magnification and diameter of the front part, should be properly selected, making the linear image from different field orthogonal to the two linear CCD. Through targeted lens system design optimization, proper selection of merit function, and tolerance analysis of the alignment and measurement principle, the acurracy of azimuth measurement of this system is less than ±2.5″, within field of view of 1.5°×1.5°, at the measurement distance of 10 m, additionally with relatiely small system length, and relatively loose tolerance. The proposed system can solve the problem of the limited size of light source cooperation target, making a low cost and large size photo-electronic detector. © 2016, Science Press. All right reserved. (11 refs.)Main Heading: LensesControlled terms: Fits and tolerances - Light sources - Optical design - Optical systems - TelescopesUncontrolled terms: Cylindrical lens - Electronic detectors - Height Measurement - Integrated measurements - Lens system designs - Long focal lengths - Size of light source - Tolerance analysisClassification Code: 741.1 Light/OpticsLight/Optics - 741.3 Optical Devices and SystemsOptical Devices and Systems
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Discriminative transfer subspace learning via low-rank and sparse representation
Xu, Yong1, 2; Fang, Xiaozhao1; Wu, Jian1; Li, Xuelong3; Zhang, David4 Source: IEEE Transactions on Image Processing, v 25, n 2, p 850-863, February 2016
; ISSN: 10577149; DOI: 10.1109/TIP.2015.2510498; Article number: 7360924;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 Bio-Computing Research Center, Shenzhen Graduate School, Harbin Institute of Technology, Shenzhen; 518055, China2 Key Laboratory of Network Oriented Intelligent Computation, Shenzhen; 518055, China3 State Key Laboratory of Transient Optics and Photonics, Center for Optical Imagery Analysis and Learning, Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China4 Biometrics Research Center, Hong Kong Polytechnic University, Hong Kong, Hong Kong
Abstract: In this paper, we address the problem of unsupervised domain transfer learning in which no labels are available in the target domain. We use a transformation matrix to transfer both the source and target data to a common subspace, where each target sample can be represented by a combination of source samples such that the samples from different domains can be well interlaced. In this way, the discrepancy of the source and target domains is reduced. By imposing joint low-rank and sparse constraints on the reconstruction coefficient matrix, the global and local structures of data can be preserved. To enlarge the margins between different classes as much as possible and provide more freedom to diminish the discrepancy, a flexible linear classifier (projection) is obtained by learning a non-negative label relaxation matrix that allows the strict binary label matrix to relax into a slack variable matrix. Our method can avoid a potentially negative transfer by using a sparse matrix to model the noise and, thus, is more robust to different types of noise. We formulate our problem as a constrained low-rankness and sparsity minimization problem and solve it by the inexact augmented Lagrange multiplier method. Extensive experiments on various visual domain adaptation tasks show the superiority of the proposed method over the state-of-the art methods. The MATLAB code of our method will be publicly available at http://www.yongxu.org/lunwen.html. © 2015 IEEE. (42 refs.)Main Heading: Transfer matrix methodControlled terms: Knowledge management - Lagrange multipliers - Linear transformations - MATLAB - Matrix algebra - Metadata - Problem solvingUncontrolled terms: Knowledge transfer - Low-rank and sparse constraints - Source domain - Subspace learning - Target domainClassification Code: 723.5 Computer ApplicationsComputer Applications - 921 MathematicsMathematics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Design and fabrication of CGH for 600mm diameter SiC primary mirror surface figure testing
Pang, Zhihai1; Ma, Zhen1; Fan, Xuewu1; Zou, Gangyi1 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 9684, 2016, 8th International Symposium on Advanced Optical Manufacturing and Testing Technology: Optical Test, Measurement Technology, and Equipment
; ISSN: 0277786X, E-ISSN: 1996756X; ISBN-13: 9781628419191; DOI: 10.1117/12.2243443; Article number: 96842J; Conference: 8th International Symposium on Advanced Optical Manufacturing and Testing Technology: Optical Test, Measurement Technology, and Equipment, AOMATT 2016, April 26, 2016 - April 29, 2016; Sponsor: Chinese Academy of Sciences, Institute of Optics and Electronics (IOE); The Chinese Optical Society (COS);
Publisher: SPIEAuthor affiliation: 1 Space Optics Laboratory, Xi'an Institute of Optics and Precision Mechanics, CAS, Shanxi Xi'an; 710119, China
Abstract: Computer-generated hologram (CGH) is an effective way to compensate wavefront aberration in null test of aspheric surfaces and freeform surfaces. Our strategies of CGH design for 600mm diameter SiC primary mirror surface figure testing are presented, and an experiment demonstrating the compensation test results of CGH is reported. We design a CGH including two sections on the same substrate in order to align the CGH to the incident wavefront: main section for compensating wavefront in null test, alignment section for adjusting the relative position between CGH and interferometer. In order to isolate different orders of diffraction, we used power carrier to make different orders of diffraction come to focus at different position along the axis to avoid ghost reflections. We measured the 600mm diameter SiC primary mirror using this CGH, and the surface test result is 0.033 rms. © 2016 SPIE. (10 refs.)Main Heading: Optical testingControlled terms: Aberrations - Alignment - Computer generated holography - Diffraction - Electron holography - Holograms - Manufacture - Mirrors - Silicon carbide - WavefrontsUncontrolled terms: Aspheric surfaces - Computer generated holograms - Free-form surface - Ghost reflections - Power carrier - Primary mirrors - Relative positions - Wavefront aberrationsClassification Code: 537.1 Heat Treatment ProcessesHeat Treatment Processes - 601.1 Mechanical DevicesMechanical Devices - 741.3 Optical Devices and SystemsOptical Devices and Systems - 743 HolographyHolography - 743.1 Holographic TechniquesHolographic Techniques - 804.2 Inorganic CompoundsInorganic Compounds
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Dehazing method for hyperspectral remote sensing imagery with hyperspectral linear unmixing
Gan, Yuquan1; Hu, Bingliang1; Wen, Desheng1; Wang, Shuang1 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 10156, 2016, Hyperspectral Remote Sensing Applications and Environmental Monitoring and Safety Testing Technology
; ISSN: 0277786X, E-ISSN: 1996756X; ISBN-13: 9781510607705; DOI: 10.1117/12.2246656; Article number: 1015613; Conference: International Symposium on Hyperspectral Remote Sensing Applications and the International Symposium on Environmental Monitoring and Safety Testing Technology, May 9, 2016 - May 11, 2016; Sponsor: China High-Tech Industrialization Association (CHIA); Chinese Society for Optical Engineering (CSOE);
Publisher: SPIEAuthor affiliation: 1 Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, No. 17 Xinxi Road, Xi'an, China
Abstract: Haze always exists in hyper-spectral remote sensing imagery, and it is a key reason that influences the effective information extraction of hyper-spectral images. Specially, when the faint haze covers part of the target in remote sensing images, the target still can be detected but not clear. So, how to remove the influence of the haze and improve the applicable efficiency of hyper-spectral images is a popular research point. This paper proposes a dehazing method for hyper-spectral images based on linear unmixing. First, a popular hyper-spectral unmixing method called FUN is used to get the signature of all the end-members and their corresponding abundance. And then, the abundance of the haze end-member is removed and the abundances of the rest end-members are adjusted to satisfy the sum-To-one and non-negative constraint. Lastly, the new abundance and the signature of the end-members are linearly mixed to get the dehazed hyper-spectral images. The experiment result shows that the dehazed hyper-spectral images exhibit better target information and details. The method is effective and available. © 2016 SPIE. (16 refs.)Main Heading: Remote sensingControlled terms: Demulsification - Environmental engineering - Environmental technology - Image processing - Image reconstruction - Safety testing - SpectroscopyUncontrolled terms: Dehazing - Endmember extraction - Hyper-spectral images - Hyperspectral remote sensing - Linear unmixing - Remote sensing imagery - Remote sensing images - Target informationClassification Code: 454 Environmental EngineeringEnvironmental Engineering - 802.3 Chemical OperationsChemical Operations - 914.1 Accidents and Accident PreventionAccidents and Accident Prevention
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Applications of photonic crystal in wavelength multiplex visualization
Qian, Shi1; Lei, Zhang1 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 10154, 2016, Advanced Optical Design and Manufacturing Technology and Astronomical Telescopes and Instrumentation
; ISSN: 0277786X, E-ISSN: 1996756X; DOI: 10.1117/12.2247307; Article number: 101541V; Conference: International Symposium on Advanced Optical Design and Manufacturing Technologies and International Symposium on Astronomical Telescope and Instrumentation, May 9, 2016 - May 11, 2016; Sponsor: China High-Tech Industrialization Association (CHIA); Chinese Society for Optical Engineering (CSOE);
Publisher: SPIEAuthor affiliation: 1 Xi'an Institute of Optics and Precision Mechanics of Cas, University of Chinese Academy of Sciences, Xi'an; 710119, China
Abstract: The triple-channel photonic crystal filters are proposed designed. These devices have advantages of better filtering effect and high wavelength accuracy. In wavelength multiplex visualization, these filters can bring different wavelength of view entering into eyes so that stereo images are formed. we discuss the problem about minimization of the angle shift.The simulation shows that higher-index material and more high-index material in a basic period can decrease the angle shift. © 2016 SPIE. (18 refs.)Main Heading: Crystal filtersControlled terms: Manufacture - Multiplexing - Optical design - Photonic crystals - Radio telescopes - Stereo image processing - Telescopes - VisualizationUncontrolled terms: Filtering effects - High Index materials - Higher index - Multi channel - Stereo imaging - Stereo-image - Visual optics - Wavelength accuracyClassification Code: 537.1 Heat Treatment ProcessesHeat Treatment Processes - 657.2 Extraterrestrial Physics and Stellar PhenomenaExtraterrestrial Physics and Stellar Phenomena - 703.2 Electric FiltersElectric Filters - 723.2 Data Processing and Image ProcessingData Processing and Image Processing - 741.1 Light/OpticsLight/Optics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Nonlinear resonant Auger spectroscopy in CO using an x-ray pump-control scheme
Zhang, Song Bin1, 2, 3; Kimberg, Victor4, 5; Rohringer, Nina2, 3 Source: Physical Review A, v 94, n 6, December 12, 2016
; ISSN: 24699926, E-ISSN: 24699934; DOI: 10.1103/PhysRevA.94.063413; Article number: 063413;
Publisher: American Physical SocietyAuthor affiliation: 1 School of Physics and Information Technology, Shaanxi Normal University, Xi'an; 710119, China2 Max Planck Institute for the Structure and Dynamics of Matter (MPSD), Hamburg; 22761, Germany3 Center for Free-Electron Laser Science (CFEL), Hamburg; 22761, Germany4 Department of Theoretical Chemistry and Biology, School of Biotechnology, Royal Institute of Technology, Stockholm; S-106 91, Sweden5 Laboratory for Nonlinear Optics and Spectroscopy, Siberian Federal University, Krasnoyarsk; 660041, Russia
Abstract: In the present paper we propose nonlinear femtosecond x-ray pump-probe spectroscopy to study the vibrational dynamics of a core-excited molecular state and discuss numerical results in CO. A femtosecond pump resonantly excites the carbon core-excited 1s-1π∗ state of the CO molecule. A second strong probe (control) pulse is applied at variable delay and is resonantly coupled to a valence excited state of the molecule. The strong nonlinear coupling of the control pulse induces Rabi flopping between the two electronic states. During this process, a vibrational wave packet in the core-excited state is created, which can be effectively manipulated by changing the time delay between pump and control pulses. We present an analysis of the resonant Auger electron spectrum and the transient absorption or emission spectrum on the pump transition and discuss their information content for reconstruction of the vibrational wave packet. © 2016 American Physical Society. (60 refs.)Main Heading: Auger electron spectroscopyControlled terms: Absorption spectroscopy - Augers - Carbon - Delay control systems - Emission spectroscopy - Excited states - Molecules - Optical pumping - Probes - Time delay - Wave packetsUncontrolled terms: Core-excited state - Information contents - Resonant Auger spectroscopy - Strong nonlinear coupling - Transient absorption - Vibrational dynamics - Vibrational wave packets - X ray pump-probe spectroscopyClassification Code: 502.2 Mine and Quarry EquipmentMine and Quarry Equipment - 713 Electronic CircuitsElectronic Circuits - 731.1 Control SystemsControl Systems - 804 Chemical Products GenerallyChemical Products Generally - 931.3 Atomic and Molecular PhysicsAtomic and Molecular Physics - 931.4 Quantum Theory; Quantum MechanicsQuantum Theory; Quantum Mechanics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Measurement of excited layer thickness in highly photo-excited GaAs
Liang, Lingliang1, 2, 3; Tian, Jinshou1; Wang, Tao1; Wu, Shengli3; Li, Fuli3; Gao, Guilong1, 2, 3 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 10155, 2016, Optical Measurement Technology and Instrumentation
; ISSN: 0277786X, E-ISSN: 1996756X; ISBN-13: 9781510607682; DOI: 10.1117/12.2246652; Article number: 101551Q; Conference: International Symposium on Optical Measurement Technology and Instrumentation, May 9, 2016 - May 11, 2016; Sponsor: China High-Tech Industrialization Association (CHIA); Chinese Society for Optical Engineering (CSOE);
Publisher: SPIEAuthor affiliation: 1 Xi'an Institute of Optics and Precision Mechanics of Chinese Academy of Science, State Key Laboratory of Transient Optics and Photonics, No.17 Xinxi Road, Xi'an; 710119, China2 Graduate University of Chinese, Academy of Sciences, No.19 Yuquan Road, Beijing; 100049, China3 Xi'an Jiaotong University, No.28 Xianning Road, Xi'an; 710049, China
Abstract: Highly photo-excited layer thickness in GaAs is measured using a pump probe arrangement. A normally incident pump illumination spatially modulated by a mask will induce a corresponding refractive index change distribution in the depth direction due to edge scattering and attenuation absorption effect, which can deflect the probe beam passing through this excited region. Maximum deflection of the probe beam will be limited by the thickness of excited layer, and thus can also be employed to measure the thickness of the photo-excited layer of the material. Theoretical calculation confirms the experimental results. This method can find its application in measurements of photo-excited layer thickness of many kinds of materials and be significant to study the characteristics of materials in laser machining, grating and waveguide fabricating. © 2016 SPIE. (14 refs.)Main Heading: Refractive indexControlled terms: Gallium arsenide - Optical data processing - Optical variables measurement - Probes - Semiconducting galliumUncontrolled terms: Absorption effects - Maximum deflection - Optical beam deflection - Photo-excited layer - Pump probe - Refractive index changes - Spatially modulated - Theoretical calculationsClassification Code: 712.1.1 Single Element Semiconducting MaterialsSingle Element Semiconducting Materials - 723.2 Data Processing and Image ProcessingData Processing and Image Processing - 741.1 Light/OpticsLight/Optics - 804 Chemical Products GenerallyChemical Products Generally - 941.4 Optical Variables MeasurementsOptical Variables Measurements
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Research on photodiode detector-based spatial transient light detection and processing system
Liu, Meiying1; Wang, Hu1; Liu, Yang1; Zhao, Hui1; Nan, Meng2 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 10156, 2016, Hyperspectral Remote Sensing Applications and Environmental Monitoring and Safety Testing Technology
; ISSN: 0277786X, E-ISSN: 1996756X; ISBN-13: 9781510607705; DOI: 10.1117/12.2246843; Article number: 1015619; Conference: International Symposium on Hyperspectral Remote Sensing Applications and the International Symposium on Environmental Monitoring and Safety Testing Technology, May 9, 2016 - May 11, 2016; Sponsor: China High-Tech Industrialization Association (CHIA); Chinese Society for Optical Engineering (CSOE);
Publisher: SPIEAuthor affiliation: 1 Xi'an Institute of Optics and Precision Mechanics of CAS, Xi'an; 710119, China2 Chinese People's Liberation Army in Xi'an Academy of Telecommunications, 710106, China
Abstract: In order to realize real-Time signal identification and processing of spatial transient light, the features and the energy of the captured target light signal are first described and quantitatively calculated. Considering that the transient light signal has random occurrence, a short duration and an evident beginning and ending, a photodiode detector based spatial transient light detection and processing system is proposed and designed in this paper. This system has a large field of view and is used to realize non-imaging energy detection of random, transient and weak point target under complex background of spatial environment. Weak signal extraction under strong background is difficult. In this paper, considering that the background signal changes slowly and the target signal changes quickly, filter is adopted for signal's background subtraction. A variable speed sampling is realized by the way of sampling data points with a gradually increased interval. The two dilemmas that real-Time processing of large amount of data and power consumption required by the large amount of data needed to be stored are solved. The test results with self-made simulative signal demonstrate the effectiveness of the design scheme. The practical system could be operated reliably. The detection and processing of the target signal under the strong sunlight background was realized. The results indicate that the system can realize real-Time detection of target signal's characteristic waveform and monitor the system working parameters. The prototype design could be used in a variety of engineering applications. © 2016 SPIE. (8 refs.)Main Heading: Signal detectionControlled terms: Environmental engineering - Environmental technology - Photodiodes - Remote sensing - Safety engineering - Safety testingUncontrolled terms: Background subtraction - Characteristic waveforms - Engineering applications - Large field of views - Photodiode detector - Real-time detection - Realtime processing - Spatial environmentsClassification Code: 454 Environmental EngineeringEnvironmental Engineering - 716.1 Information Theory and Signal ProcessingInformation Theory and Signal Processing - 914 Safety EngineeringSafety Engineering - 914.1 Accidents and Accident PreventionAccidents and Accident Prevention
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


A low-rank tensor decomposition based hyperspectral image compression algorithm
Zhang, Mengfei1; Du, Bo1; Zhang, Lefei1; Li, Xuelong2 Source: Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), v 9916 LNCS, p 141-149, 2016, Advances in Multimedia Information Processing – 17th Pacific-Rim Conference on Multimedia, PCM 2016, Proceedings
; ISSN: 03029743, E-ISSN: 16113349; ISBN-13: 9783319488899; DOI: 10.1007/978-3-319-48890-5_14; Conference: 17th Pacific-Rim Conference on Multimedia, PCM 2016, September 15, 2016 - September 16, 2016;
Publisher: Springer VerlagAuthor affiliation: 1 School of Computer, Wuhan University, Wuhan, China2 Center for OPTIMAL, State Key Laboratory of Transient Optics and Photonics, Xi’an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi’an, China
Abstract: Hyperspectral image (HSI), which is widely known that contains much richer information in spectral domain, has attracted increasing attention in various fields. In practice, however, since a hyperspectral image itself contains large amount of redundant information in both spatial domain and spectral domain, the accuracy and efficiency of data analysis is often decreased. Various attempts have been made to solve this problem by image compression method. Many conventional compression methods can effectively remove the spatial redundancy but ignore the great amount of redundancy exist in spectral domain. In this paper, we propose a novel compression algorithm via patch-based low-rank tensor decomposition (PLTD). In this framework, the HSI is divided into local third-order tensor patches. Then, similar tensor patches are grouped together and to construct a fourth-order tensor. And each cluster can be decomposed into smaller coefficient tensor and dictionary matrices by low-rank decomposition. In this way, the redundancy in both the spatial and spectral domains can be effectively removed. Extensive experimental results on various public HSI datasets demonstrate that the proposed method outperforms the traditional image compression approaches. © Springer International Publishing AG 2016. (28 refs.)Main Heading: Image compressionControlled terms: Compaction - Image reconstruction - Redundancy - Spectroscopy - Strain measurement - TensorsUncontrolled terms: Compression algorithms - Compression approach - Hyper-spectral images - Hyperspectral image compression - Image compression methods - Low-rank decomposition - Tensor decomposition - Tensor representationClassification Code: 921.1 AlgebraAlgebra - 943.2 Mechanical Variables MeasurementsMechanical Variables Measurements
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Compression solid super-continuum to 7.1fs/0.68 mJ for driving high harmonic generation
Liu, Yangyang1; He, Peng2; Zhao, Kun1; Teng, Hao1; He, Xinkui1; Huang, Pei1, 3; Huang, Hangdong2; Zhong, Shiyang1; Jiang, Yujiao2; Hou, Xun3; Wei, Zhiyi1 Source: Optics InfoBase Conference Papers, March 14, 2016, Compact EUV and X-ray Light Sources, EUVXRAY 2016; ISBN-13: 9781943580095; Article number: ET5A.6; Conference: Compact EUV and X-ray Light Sources, EUVXRAY 2016, March 20, 2016 - March 22, 2016; Sponsor: Energetiq Technology,Inc.; JTEC Corporation; OSA; Qubig; Radia Beam Technologies;
Publisher: OSA - The Optical SocietyAuthor affiliation: 1 Institute of Physics, Chinese Academy of Sciences, Beijing; 100190, China2 School of Physics and Optoelectronics Engineering, Xidian University, Xi'an; 710071, China3 Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China
Abstract: We generated white-continuum covered 450-1000nm with 85% efficiency by injected 25fs Ti:Sapphire laser at 1kHz repetition rate into fused silica pieces. With the 7.1 fs compressed pulses as driver, strong high harmonic generation was observed. © OSA 2016. © OSA 2016. (10 refs.)Main Heading: Laser pulsesControlled terms: Fused silica - Harmonic generation - Light sources - SapphireUncontrolled terms: Compressed pulse - High harmonic generation - Repetition rate - Super continuum - Ti: Sapphire laserClassification Code: 482.2.1 GemsGems - 744.1 Lasers, GeneralLasers, General - 812.3 GlassGlass
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


High-energy pulse fiber lasers
Liu, Xueming1 Source: Optics InfoBase Conference Papers, July 21, 2014, Asia Communications and Photonics Conference, ACPC 2016; ISBN-13: 9780960038008; DOI: 10.1364/ACPC.2016.AS1A.2; Conference: Asia Communications and Photonics Conference, ACPC 2016, November 2, 2016 - November 5, 2016; Sponsor: CHINA INSTITUTE OF COMMUNICATIONS; IEEE Photonics society; OSA-The Optical Society; SPIE; The CHINESE OPTICAL SOCITETY;
Publisher: OSA - The Optical SocietyAuthor affiliation: 1 Xi'an Inst of Optics and Precision Mech, Xi'an, Shaanxi, China
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Generation of multiple entangled qubits from an integrated frequency comb source
Reimer, Christian1; Kues, Michael1; Roztocki, Piotr1; Wetzel, Benjamin1, 2; Bromberg, Yaron3; Little, Brent E.4; Chu, Sai T.5; Moss, David J.6; Caspani, Lucia1, 7; Morandotti, Roberto1 Source: Optics InfoBase Conference Papers, July 21, 2014, Integrated Photonics Research, Silicon and Nanophotonics, IPRSN 2016; ISBN-13: 9781943580149; Conference: Integrated Photonics Research, Silicon and Nanophotonics, IPRSN 2016, July 18, 2016 - July 20, 2016; Sponsor: AMERICAN ELEMENTS; NUFERN; OSA; Yenista Optics;
Publisher: OSA - The Optical SocietyAuthor affiliation: 1 INRS-EMT, 1650 Boulevard Lionel-Boulet, Varennes; QC; J3X 1S2, Canada2 Department of Physics and Astronomy, University of Sussex, Falmer, Brighton; BN1 9RH, United Kingdom3 Department of Applied Physics, Yale University, New Haven; CT; 06520, United States4 Xi'an Institute of Optics and Precision Mechanics of CAS, Xi'an, China5 Department of Physics and Material Science, City University of Hong Kong, Tat Chee Avenue, Hong Kong6 Centre for Micro Photonics, Swinburne University of Technology, Hawthorne; VIC; 3122, Australia7 School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh; EH14 4AS, United Kingdom
Abstract: Exploiting spontaneous four-wave mixing within an integrated CMOS-compatible microring resonator, we demonstrate the simultaneous generation of multiple time-bin entangled photon pairs, confirmed by quantum interference and state tomography with fidelities above 86%. © OSA 2016. (13 refs.)Main Heading: Quantum entanglementControlled terms: Four wave mixing - Mixer circuits - Nanophotonics - Photonics - Quantum theoryUncontrolled terms: CMOS Compatible - Entangled photon pairs - Entangled qubits - Frequency combs - Microring resonator - Quantum interference - Spontaneous four-wave mixing - State tomographyClassification Code: 713.3 Modulators, Demodulators, Limiters, Discriminators, MixersModulators, Demodulators, Limiters, Discriminators, Mixers - 741.1 Light/OpticsLight/Optics - 931.4 Quantum Theory; Quantum MechanicsQuantum Theory; Quantum Mechanics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Thin film wavelength converters for photonic integrated circuits
Chang, Lin1; Li, Yifei1; Volet, Nicolas1; Wang, Leiran1, 2; Peters, Jon1; Bowers, John E.1 Source: Optica, v 3, n 5, p 531-535, May 20, 2016
; ISSN: 23342536; DOI: 10.1364/OPTICA.3.000531;
Publisher: OSA - The Optical SocietyAuthor affiliation: 1 Department of Electrical and Computer Engineering, University of California, Santa Barbara; CA; 93106, United States2 State Key Laboratory of Transient Optics and Photonics, Xi’an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi’an; 710119, China
Abstract: Quasi-phase-matched (QPM) wavelength converters are highly desirable for emerging nonlinear optics applications in photonic integrated circuits, but available waveguide and quasi-phase-matching technologies have so far constrained their realization. In this work, we present a periodically poled lithium niobate (LN) waveguide on a silicon nitride-thin film LN platform. It contains a submicrometer waveguide core for enhancing nonlinear interactions that is more than one order of magnitude smaller than those of previous QPM waveguides. Periodic poling was applied directly to the thin film LN for quasi-phase-matching by a new surface poling technology. We demonstrated 160% W-1· cm-2normalized efficiency for second harmonic generation at 1530 nm with ultralow propagation loss (0.3 dB/cm) in the telecom band. This highly efficient and compact wavelength converter has the potential for straightforward integration with various photonic platforms, e.g., on-chip microsystems such as optical communication networks, quantum storage, and optical frequency referencing. © 2016 Optical Society of America. (25 refs.)Main Heading: Photonic integration technologyControlled terms: Harmonic generation - Integrated circuits - Mixer circuits - Niobium compounds - Nonlinear optics - Optical communication - Optical films - Phase matching - Photonic devices - Silicon nitride - Thin film circuits - Thin films - Timing circuits - WaveguidesUncontrolled terms: Harmonic generation and mixing - Lithium niobate - Nonlinear interactions - Periodically poled lithium niobate - Photonic integrated circuits - Quasi phase matching - Silicon nitride thin films - Wavelength converterClassification Code: 713 Electronic CircuitsElectronic Circuits - 714.2 Semiconductor Devices and Integrated CircuitsSemiconductor Devices and Integrated Circuits - 714.3 WaveguidesWaveguides - 717.1 Optical Communication SystemsOptical Communication Systems - 741.1.1 Nonlinear OpticsNonlinear Optics - 741.3 Optical Devices and SystemsOptical Devices and Systems - 804.2 Inorganic CompoundsInorganic Compounds
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Fuzzy bag of words for social image description
Li, Yanshan1, 2, 3; Liu, Weiming2; Huang, Qinghua1; Li, Xuelong4 Source: Multimedia Tools and Applications, v 75, n 3, p 1371-1390, February 1, 2016
; ISSN: 13807501, E-ISSN: 15737721; DOI: 10.1007/s11042-014-2138-4;
Publisher: Springer New York LLCAuthor affiliation: 1 School of Electronic and Information Engineering, South China University of Technology, Guangzhou, China2 School of Civil Engineering and Transportation, South China University of Technology, Guangzhou, China3 Shenzhen University, Shenzhen, China4 The Center for OPTical IMagery Analysis and Learning (OPTIMAL), State Key Laboratory of Transient Optics and Photonics, Xi’an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi’an; Shaanxi, China
Abstract: Rapid growth of social media resources brings huge challenges and opportunities for image description technologies. The performance of image description method directly affects the accuracy of image retrieval, image annotation and image recognition. Bag of Words (BoW) as an efficient approach to describing the images has been attracting more and more attention. However, in traditional BoW, the maps between the words in the codebook and the features extracted from the images are actually ambiguous. As the Fuzzy Sets Theory (FST) is a powerful means for dealing with uncertainty efficiently, we utilize the FST to solve the problem caused by the ambiguity between the features and words. Accordingly, we propose a new type of BoW named as FBoW to describe images based on FST. Firstly, the features are extracted from the images. Secondly, k-means is utilized to learn the codebook. Thirdly, a fuzzy membership function is designed to measure the similarity between the features and words. The optimal parameters of the fuzzy membership function are obtained by using a Genetic Algorithm (GA). The histogram is generated by adding up the fuzzy membership values of each word to describe the images. The experimental results show that the proposed FBoW outperforms traditional BoW for social image description. © 2014, Springer Science+Business Media New York. (36 refs.)Main Heading: Image retrievalControlled terms: Fuzzy set theory - Fuzzy sets - Genetic algorithms - Image processing - Image recognition - Membership functionsUncontrolled terms: Bag of words - Fuzzy membership function - Fuzzy membership values - Fuzzy sets theory - Image annotation - Image descriptions - Optimal parameter - Social imagesClassification Code: 921 MathematicsMathematics - 921.4 Combinatorial Mathematics, Includes Graph Theory, Set TheoryCombinatorial Mathematics, Includes Graph Theory, Set Theory
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Synthesized computational aesthetic evaluation of photos
Wang, Weining1; Cai, Dong1; Wang, Li1; Huang, Qinghua1; Xu, Xiangmin1; Li, Xuelong2 Source: Neurocomputing, v 172, p 244-252, January 8, 2016
; ISSN: 09252312, E-ISSN: 18728286; DOI: 10.1016/j.neucom.2014.12.106;
Publisher: ElsevierAuthor affiliation: 1 School of Electronic and Information Engineering, South China University of Technology, Guangzhou, Guangdong, China2 The Center for Optical Imagery Analysis and Learning (OPTIMAL), State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, Shaanxi, China
Abstract: Assessing aesthetic appeal of images is a highly subjective task which has attracted a lot of interests recently. It is an interdisciplinary subject related to art, psychology, and computer vision. In this paper, we systematically study prior researches of feature extraction in this area, and category them into four groups, low level, rule based, information theory, and visual attention. In each group, the effectiveness and limitations of existing features are examined. Based on the analysis, we propose a comprehensive feature set, which include 16 novel features and 70 well proved features. With this feature set, we build the system under machine learning scheme consisting of an SVM based classifier to estimate if an image is high aesthetic or low aesthetic. The experiments are conducted on public datasets show that our comprehensive feature set outperforms conventional models that concentrate mainly on certain types of features. The combination of our features produces a promising classification accuracy of 82.4% and a good performance comparable to aesthetic rating of human. Finally, we implemented the proposed evaluation system on mobile devices. It can provide real-time feedback to help users capture appealing photos. © 2015 Elsevier B.V. (47 refs.)Main Heading: Classification (of information)Controlled terms: Artificial intelligence - Behavioral research - Computation theory - Computer vision - Extraction - Feature extraction - Image processing - Information theory - Learning systems - Mobile devicesUncontrolled terms: Aesthetic evaluation - Classification accuracy - Computational aesthetics - Conventional models - Mobile applications - Photo - SVM-based classifiers - System on mobile devices
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Video parsing via spatiotemporally analysis with images
Li, Xuelong1; Mou, Lichao1; Lu, Xiaoqiang1 Source: Multimedia Tools and Applications, v 75, n 19, p 11961-11976, October 1, 2016
; ISSN: 13807501, E-ISSN: 15737721; DOI: 10.1007/s11042-015-2735-x;
Publisher: Springer New York LLCAuthor affiliation: 1 Center for OPTical IMagery Analysis and Learning (OPTIMAL), State Key Laboratory of Transient Optics and Photonics, Xi’an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi’an; Shaanxi; 710119, China
Abstract: Effective parsing of video through the spatial and temporal domains is vital to many computer vision problems because it is helpful to automatically label objects in video instead of manual fashion, which is tedious. Some literatures propose to parse the semantic information on individual 2D images or individual video frames, however, these approaches only take use of the spatial information, ignore the temporal continuity information and fail to consider the relevance of frames. On the other hand, some approaches which only consider the spatial information attempt to propagate labels in the temporal domain for parsing the semantic information of the whole video, yet the non-injective and non-surjective natures can cause the black hole effect. In this paper, inspirited by some annotated image datasets (e.g., Stanford Background Dataset, LabelMe, and SIFT-FLOW), we propose to transfer or propagate such labels from images to videos. The proposed approach consists of three main stages: I) the posterior category probability density function (PDF) is learned by an algorithm which combines frame relevance and label propagation from images. II) the prior contextual constraint PDF on the map of pixel categories through whole video is learned by the Markov Random Fields (MRF). III) finally, based on both learned PDFs, the final parsing results are yielded up to the maximum a posterior (MAP) process which is computed via a very efficient graph-cut based integer optimization algorithm. The experiments show that the black hole effect can be effectively handled by the proposed approach. © 2015, Springer Science+Business Media New York. (38 refs.)Main Heading: Probability density functionControlled terms: Algorithms - Computer vision - Formal languages - Graphic methods - Gravitation - Integer programming - Markov processes - Optimization - Semantics - Stars - Structural framesUncontrolled terms: Contextual constraints - Markov Random Felds (MRF) - Maximum a posteriors - Transfer learning - Video parsing
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Material research on the InGaAs-emitting-layer VECSEL grown on GaAs substrate
Lin, Tao1; Sun, Ruijuan1; Sun, Hang1; Guo, Enmin1; Duan, Yupeng2; Lin, Nan3; Ma, Xiaoyu3; Wang, Yonggang4 Source: Materials Science in Semiconductor Processing, v 42, p 283-287, February 1, 2016
; ISSN: 13698001; DOI: 10.1016/j.mssp.2015.11.002;
Publisher: Elsevier LtdAuthor affiliation: 1 Department of Electronic Engineering, Xi'An University of Technology, Xi'an, China2 Department of Physics, Northwest University, Xi'an, China3 Institute of Semiconductors, Chinese Academy of Sciences, Beijing, China4 Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, China
Abstract: Wafers of InGaAs-emitting-layer vertical external cavity surface emitting semiconductor laser (VECSEL) gain chip and separate active region were grown on semi-insulator GaAs substrates by low pressure metal-organic vapor phase epitaxy (MOVPE). Photoluminescence (PL) wavelength of the active region could be adjusted linearly about 1 nm for increasing 1 sccm H2flow rate through TMIn under AsH3flow rates of 150 sccm. The complicated surface-emitted PL signal of the VECSEL gain chip was strongly modulated by interferences within the multilayer and was interpreted by the aberrance of the quantum wells emission with a profile filtered by a micro-cavity resonance in the longitudinal confinement factor. Material tests of the VECSEL wafer showed the reflectivity of the DBR mirrors was in good agreement with the active region photoluminescence, and the wafer was obtained with high crystal quality. © 2015 Elsevier Ltd. All rights reserved. (16 refs.)Main Heading: Surface emitting lasersControlled terms: Gallium arsenide - Metallorganic vapor phase epitaxy - Optical testing - Organic lasers - Organometallics - Photoluminescence - Quantum well lasers - Semiconducting gallium - Semiconducting indium - Semiconductor quantum wells - Silicon wafers - SubstratesUncontrolled terms: Complicated surface - Confinement factor - Crystal qualities - InGaAs - Low pressure metal organic vapor-phase epitaxies - Material research - VECSEL - Vertical external-cavity surface-emitting semiconductor laserClassification Code: 712.1.1 Single Element Semiconducting MaterialsSingle Element Semiconducting Materials - 714.2 Semiconductor Devices and Integrated CircuitsSemiconductor Devices and Integrated Circuits - 741.1 Light/OpticsLight/Optics - 741.3 Optical Devices and SystemsOptical Devices and Systems - 744.1 Lasers, GeneralLasers, General - 744.7 Laser ComponentsLaser Components - 804 Chemical Products GenerallyChemical Products Generally - 804.1 Organic CompoundsOrganic Compounds - 933.1.2 Crystal GrowthCrystal Growth
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


An Orthogonal Method for Measurement Matrix Optimization
Pan, Jinfeng1, 2, 3; Qiu, Yuehong1 Source: Circuits, Systems, and Signal Processing, v 35, n 3, p 837-849, March 1, 2016
; ISSN: 0278081X, E-ISSN: 15315878; DOI: 10.1007/s00034-015-0107-4;
Publisher: Birkhauser BostonAuthor affiliation: 1 Space Optics Laboratory, Xi’an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi’an, China2 University of Chinese Academy of Sciences, Beijing, China3 School of Electric and Electronic Engineering, Shandong University of Technology, Zibo, China
Abstract: Compressive sensing theory states that signals can be sampled at a much smaller rate than that required by the Nyquist sampling theorem, because the sampling of a signal in the former is performed as a relatively small number of its linear measurements. Thus, the design of a measurement matrix is important in compressive sensing framework. A random measurement matrix optimization method is proposed in this study based on the incoherence principle of compressive sensing, which requires the mutual coherence of information operator to be small. The columns with mutual coherence are orthogonalized iteratively to decrease the mutual coherence of the information operator. The orthogonalization is realized by replacing the columns with the orthogonal matrix (Formula presented.) of their QR factorization. An information operator with smaller mutual coherence is acquired after the optimization, leading to an improved measurement matrix in terms of its relationship with the information operator. Results of several experiments show that the improved measurement matrix can reduce its mutual coherence with dictionaries compared with the random measurement matrix. The signal reconstruction error also decreases when the optimized measurement matrix is utilized. © 2015, Springer Science+Business Media New York. (32 refs.)Main Heading: Matrix algebraControlled terms: Compressed sensing - Factorization - Iterative methods - Signal reconstruction - Signal samplingUncontrolled terms: Compressive sensing - Information operators - Measurement matrix - Mutual coherence - Nyquist sampling theorem - Optimized measurement matrixes - Orthogonalization - QR factorizationsClassification Code: 716.1 Information Theory and Signal ProcessingInformation Theory and Signal Processing - 921 MathematicsMathematics - 922 Statistical MethodsStatistical Methods
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Application of Grey Model GM(1, 1) to Ultra Short-Term Predictions of Universal Time
Lei, Yu1, 2, 3; Guo, Min4; Zhao, Danning1, 3; Cai, Hongbing1, 2; Hu, Dandan4 Source: Artificial Satellites, v 51, n 1, p 19-29, March 1, 2016
; ISSN: 0208841X, E-ISSN: 20836104; DOI: 10.1515/arsa-2016-0002;
Publisher: Polish Academy of SciencesAuthor affiliation: 1 National Time Service Center, Chinese Academy of Sciences, China2 Key Laboratory of Time and Frequency Primary Standards, Chinese Academy of Sciences, China3 University of Chinese Academy of Sciences, China4 Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, China
Abstract: A mathematical model known as one-order one-variable grey differential equation model GM(1, 1) has been herein employed successfully for the ultra short-term (<10days) predictions of universal time (UT1-UTC). The results of predictions are analyzed and compared with those obtained by other methods. It is shown that the accuracy of the predictions is comparable with that obtained by other prediction methods. The proposed method is able to yield an exact prediction even though only a few observations are provided. Hence it is very valuable in the case of a small size dataset since traditional methods, e.g., least-squares (LS) extrapolation, require longer data span to make a good forecast. In addition, these results can be obtained without making any assumption about an original dataset, and thus is of high reliability. Another advantage is that the developed method is easy to use. All these reveal a great potential of the GM(1, 1) model for UT1-UTC predictions. © 2016 Artificial Satellites. (18 refs.)Main Heading: ForecastingControlled terms: Differential equations - Least squares approximations - System theoryUncontrolled terms: Differential equation model - GM (1 , 1) model - Grey Model - Grey model GM(1 ,1) - High reliability - Prediction methods - Short term prediction - Universal timeClassification Code: 921.2 CalculusCalculus - 921.6 Numerical MethodsNumerical Methods - 961 Systems ScienceSystems Science
Database: Compendex
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Deployable structure design and analysis for space membrane diffractive telescope
Zheng, Yaohui1, 2; Ruan, Ping1; Cao, Shang1, 2 Source: Hongwai yu Jiguang Gongcheng/Infrared and Laser Engineering, v 45, n 1, January 25, 2016; Language: Chinese
; ISSN: 10072276; DOI: 10.3788/IRLA201645.0118004; Article number: 0118004;
Publisher: Chinese Society of AstronauticsAuthor affiliation: 1 Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, China2 University of Chinese Academy of Sciences, Beijing, China
Abstract: In order to satisfy the demand for the big aperture diffraction space telescope, a primary lenses deployable structure for space membrane diffractive telescope was investigated. Firstly, after analysis of the characteristics of diffraction imaging about the big aperture membrane diffraction telescope, the main requirements for deployable structure were put forward. Then according to these design requirements for the deployable structure, a 3D solid model was designed. Finally, with the help of Adams, a simulation model was established and analyzed. The results show that the structure under the driving of the rotating drive components is in line with the design form of exercise and achieved smooth and reliable movement. This deployable structure may provide a new train of thought for the design of large aperture membrane diffraction telescope. © 2016, Editorial Board of Journal of Infrared and Laser Engineering. All right reserved. (9 refs.)Main Heading: Structural designControlled terms: Design - Diffraction - Space opticsUncontrolled terms: 3D solid model - Aperture diffraction - Deployable mechanisms - Deployable structure - Diffraction imaging - Fold methods - Large aperture - Simulation modelClassification Code: 408.1 Structural Design, GeneralStructural Design, General - 656.1 Space FlightSpace Flight
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Dynamic properties of a small-size streak tube
Hui, Dan-Dan1, 2; Tian, Jin-Shou1; Wang, Jun-Feng1; Lu, Yu1; Wen, Wen-Long1; Xu, Xiang-Yan1 Source: Wuli Xuebao/Acta Physica Sinica, v 65, n 1, January 5, 2016; Language: Chinese
; ISSN: 10003290; DOI: 10.7498/aps.65.018502; Article number: 018502;
Publisher: Institute of Physics, Chinese Academy of SciencesAuthor affiliation: 1 Key Laboratory of Ultra-fast Photoelectric Diagnostics Technology, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, China2 University of Chinese Academy of Sciences, Beijing, China
Abstract: Scannerless (flash) lidar system based on streak camera is able to realize three-dimensional (3D) multi-spectral fluorescence imaging and 3D imaging polarimetry. Compared with conventional lidar system, the flash lidar system overcomes image distortions caused by the motion between the target and the sensor platform. Other advantages of the flash lidar system are higher image update rates and the potential for creating a miniaturized lidar system. To meet the requirements for developing this new technology, a super small-sized, large photocathode area and meshless streak tube with spherical cathode and screen is designed with the aid of computer simulation technology (CST) software. The tube with nearly 28 mm wide photocathode work area contains two electrostatic focusing lens, a pair of deflection plates, and a 50 mm diameter output screen. The external dimension of the tube is merely 50 mm×100 mm. And its electromagnetic fields are calculated in the CST Particle Studio based on the finite integration theory. Some dynamic properties of the tube are analyzed via observing different electron trajectories launched from a number of different points on the cathode. The influences of the deflector position on deflection sensitivity and spatial resolution are analyzed. Increasing the distance between the deflector and the anode pin hole leads to a worse deflection sensitivity but a better spatial resolution. As for the temporal resolution, three electron pulses separated by 30 ps can be well resolved by the streak tube in the dynamic mode. Thus, the dynamic temporal resolution of the streak tube is better than 30 ps. And a 10 lp/mm spatial resolution across the 28 mm long slit on the photocathode can be obtained by estimating modulation transfer functions of the electron trajectories. Temporal distortions at the entire photocathode working area are evaluated, and the data reveal that the larger the photocathode working area, the bigger the temporal distortions are. Also, the temporal distortion is present mainly in the photocathode-to-deflection plates region. In addition, the slit image of the streak tube working in the dynamic mode is simulated and presented. The phenomenon that the slit image is curved due to the temporal distortion is analyzed. Two rectangular electron pulses separated by 50 ps are well resolved by the streak tube. Therefore, the temporal resolution of this small-size steak tube is better than 50 ps with a rectangular slit dimension of 30 mm×50 μm on the photocathode, and its electron-optic magnification is 1.2. © 2016 Chinese Physical Society. (19 refs.)Main Heading: Tubes (components)Controlled terms: Cathodes - Computer software - Deflection (structures) - Electrodes - Electromagnetic fields - Electrons - Electrostatic lenses - High speed photography - Image resolution - Optical radar - Photocathodes - Streak cameras - TrajectoriesUncontrolled terms: Computer simulation technology (CST) - Deflection sensitivities - Electro-static focusing - Electron trajectories - Finite integration theories - Lidar systems - Meshless - Temporal distortionsClassification Code: 408.2 Structural Members and ShapesStructural Members and Shapes - 619.1 Pipe, Piping and PipelinesPipe, Piping and Pipelines - 701 Electricity and MagnetismElectricity and Magnetism - 714.1 Electron TubesElectron Tubes - 716.2 Radar Systems and EquipmentRadar Systems and Equipment - 723 Computer Software, Data Handling and ApplicationsComputer Software, Data Handling and Applications - 742.1 PhotographyPhotography - 742.2 Photographic EquipmentPhotographic Equipment
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Parameter selection and optical design of all-day star sensor
Pan, Yue1, 2; Wang, Hu1; Jing, Nan1, 2; Shen, Yang1, 2; Xue, Yao-Ke1; Liu, Jie1 Source: Guangzi Xuebao/Acta Photonica Sinica, v 45, n 1, January 1, 2016; Language: Chinese
; ISSN: 10044213; DOI: 10.3788/gzxb20164501.0122002; Article number: 0122002;
Publisher: Chinese Optical SocietyAuthor affiliation: 1 Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, China2 University of Chinese Academy of Sciences, Beijing, China
Abstract: Detecting a 4.5 magnitude star in the observation height of 10 km, the radiance of stars between 600~1100 nm was analyzed, the radiance of sky background and the optical transmission of atmosphere were calculated by using Modtran. When the threshold of SNR is 5, typical parameters are selected. With a plane mirror and a silicon material sphere lens, a lighter miniature optical system was designed. The result shows that the optical system spot shape approaches a circle between 600~1100 nm of full field of view, modulation transfer function approaches perfection and have outstanding image of quality. The Ground-based daytime and nighttime detection SNR of the star tracter is calculated and the detection ability limit is estimated in the threshold 5 of SNR, which is 2.5 stellar magnitude G star in daytime on the ground and 6 at night. © 2016, Science Press. All right reserved. (13 refs.)Main Heading: Light transmissionControlled terms: Geometrical optics - Lenses - Optical design - Optical systems - StarsUncontrolled terms: All-day - Detection ability - Field of views - Parameter selection - Silicon materials - Sky background - Spectral filtering - Star sensorsClassification Code: 657.2 Extraterrestrial Physics and Stellar PhenomenaExtraterrestrial Physics and Stellar Phenomena - 741.1 Light/OpticsLight/Optics - 741.3 Optical Devices and SystemsOptical Devices and Systems
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Research on detection sensitivity distribution regularity of lens-light-screen
Tian, Hui1, 2; Ni, Jin-Ping2; Jiao, Ming-Xing1; Hu, Xun3; Gao, Fen2 Source: Binggong Xuebao/Acta Armamentarii, v 37, n 2, p 325-331, February 1, 2016; Language: Chinese
; ISSN: 10001093; DOI: 10.3969/j.issn.1000-1093.2016.02.019;
Publisher: China Ordnance SocietyAuthor affiliation: 1 School of Mechanical and Precision Instrumental Engineering, Xi'an University of Technology, Xi'an; Shaanxi, China2 School of Optoelectronic Engineering, Xi'an Technological University, Xi'an; Shaanxi, China3 Chongqing Changan Industry (Group) Co. Ltd., Chongqing, China
Abstract: In order to meet the testing requirement of indoor optical target with large detection area, two patterns of lens-light-screen's engineering realization method are studied, of which one is sector lens-light-screen, and the other is rectangle lens-light-screen. The working principle of each kind of lens-light-screen is analyzed. The luminous flux may be changed when a flying projectile goes through the lens-light-screen in different position, of which the corresponding formulas are deduced based on the photometry principle. The sensitivity distribution regularity of each kind of lens-light-screen is simulated using Matlab. It is verified by the firing tests of air gun bullets. The results show that the signal amplitude of the projectile collected by an oscilloscope is in conformity with the sensitivity simulation results, which provides a reference for the engineering design of the optical targets with lager detection area. © 2016, China Ordnance Society. All right reserved. (18 refs.)Main Heading: LensesControlled terms: MATLAB - Photometry - ProjectilesUncontrolled terms: Detection sensitivity - Engineering design - Engineering realizations - Science and Technology - Sensitivity distributions - Sensitivity Simulation - Testing requirements - Trajectory parametersClassification Code: 741.3 Optical Devices and SystemsOptical Devices and Systems - 921 MathematicsMathematics - 941.4 Optical Variables MeasurementsOptical Variables Measurements
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Lab-on-fiber electrophoretic trace mixture separating and detecting an optofluidic device based on a microstructured optical fiber
Yang, Xinghua1, 2; Guo, Xiaohui1; Li, Song1; Kong, Depeng3; Liu, Zhihai1; Yang, Jun1; Yuan, Libo1 Source: Optics Letters, v 41, n 8, p 1873-1876, April 15, 2016
; ISSN: 01469592, E-ISSN: 15394794; DOI: 10.1364/OL.41.001873;
Publisher: OSA - The Optical SocietyAuthor affiliation: 1 Key Laboratory of In-Fiber Integrated Optics, College of Science, Harbin Engineering University, Ministry of Education, Harbin, China2 Key Laboratory of Superlight Materials and Surface Technology, Harbin Engineering University, Ministry of Education, Harbin, China3 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanic, Chinese Academy of Sciences, Xi'an, China
Abstract: We report an in-fiber integrated electrophoretic trace mixture separating and detecting an optofluidic optical fiber sensor based on a specially designed optical fiber. In this design, rapid in situ separation and simultaneous detection of mixed analytes can be realized under electro-osmotic flow in the microstructured optical fiber. To visually display the in-fiber separating and detecting process, two common fluorescent indicators are adopted as the optofluidic analytes in the optical fiber. Results show that a trace amount of the mixture (0.15 μL) can be completely separated within 3.5 min under a high voltage of 5 kV. Simultaneously, the distributed information of the separated analytes in the optical fiber can be clearly obtained by scanning along the optical fiber using a 355 nm laser. The emission from the analytes can be efficiently coupled into the inner core and guides to the remote end of the optical fiber. In addition, the thin cladding around the inner core in the optical fiber can prevent the fluorescent cross talk between the analytes in this design. Compared to previous optical fiber optofluidic devices, this device first realizes simultaneously separating treatment and the detection of the mixed samples in an optical fiber. Significantly, such an in-fiber integrated separating and detecting optofluidic device can find wide applications in various analysis fields involves mixed samples, such as biology, chemistry, and environment. © 2016 Optical Society of America. (21 refs.)Main Heading: FibersControlled terms: Chemical analysis - Crosstalk - Electroosmosis - Fluorescence - Mixtures - Optical fibersUncontrolled terms: Distributed information - Electroosmotic flow - Fluorescent indicators - Micro-structured optical fibers - Optofluidic devices - Simultaneous detection - Situ separation - Trace amountsClassification Code: 701.1 Electricity: Basic Concepts and PhenomenaElectricity: Basic Concepts and Phenomena - 741.1 Light/OpticsLight/Optics - 741.1.2 Fiber OpticsFiber Optics
Database: Compendex
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Various soliton molecules in large anomalous dispersion fiber laser
Han, Xiaoxiang1; Liu, Xueming1 Source: 2015 11th Conference on Lasers and Electro-Optics Pacific Rim, CLEO-PR 2015, v 2, January 7, 2016, 2015 11th Conference on Lasers and Electro-Optics Pacific Rim, CLEO-PR 2015; ISBN-13: 9781467371094; DOI: 10.1109/CLEOPR.2015.7376110; Article number: 7376110; Conference: 11th Conference on Lasers and Electro-Optics Pacific Rim, CLEO-PR 2015, August 24, 2015 - August 28, 2015;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, China
Abstract: Soliton molecules (SMs) induced by the spectral filtering with the phase difference of 0, π, π/2 and multiple separations are observed. It is found that the equilibrium distances of SMs are multiple and discrete. © 2015 IEEE. (22 refs.)Main Heading: SolitonsControlled terms: Fiber lasers - MoleculesUncontrolled terms: Anomalous dispersion - Equilibrium distances - Phase difference - Soliton molecules - Spectral filteringClassification Code: 744.4 Solid State LasersSolid State Lasers - 931.3 Atomic and Molecular PhysicsAtomic and Molecular Physics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Reduction of phase noise to amplitude noise conversion in silicon waveguide-based phase-sensitive amplification
Ma, Yonghua1; Liu, Hongjun1; Sun, Qibing1; Huang, Nan1; Wang, Zhaolu1 Source: Applied Optics, v 55, n 12, p 3140-3144, April 20, 2016
; ISSN: 1559128X, E-ISSN: 21553165; DOI: 10.1364/AO.55.003140;
Publisher: OSA - The Optical SocietyAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics of CAS, Xi'an, China
Abstract: We use a vector phase sensitive amplification (PSA) scheme, which can eliminate the inherent phase noise (PN) to amplitude noise (AN) conversion in a conventional PSA process. A dispersion-engineered silicon strip waveguide is used to investigate the vector PSA scheme at the telecom wavelengths. The phase-dependent gain and phase-tophase transfer functions as well as constellation diagram at different signal polarization states (SPSs) are numerically analyzed. It is found that the PN to AN conversion is completely suppressed when the SPS is identical to one of the pump polarization states. Moreover, the binary phase shift keying signal is regenerated by the proposed vector PSA scheme, and the error vector magnitude is calculated to assess the regeneration capacity. Our results have potential application in all-optical signal processing. © 2016 Optical Society of America. (27 refs.)Main Heading: VectorsControlled terms: Amplification - Binary phase shift keying - Optical signal processing - Phase noise - Phase shift - Phase shift keying - Phase shifters - Polarization - Signal processing - WaveguidesUncontrolled terms: All-optical signal processing - Amplitude-noise conversion - Binary phase-shift keying signals - Constellation diagrams - Error vector magnitude - Phase-sensitive amplifications - Regeneration capacity - Signal polarizationClassification Code: 701.2 Magnetism: Basic Concepts and PhenomenaMagnetism: Basic Concepts and Phenomena - 713.5 Electronic Circuits Other Than Amplifiers, Oscillators, Modulators, Limiters, Discriminators or MixersElectronic Circuits Other Than Amplifiers, Oscillators, Modulators, Limiters, Discriminators or Mixers - 714.3 WaveguidesWaveguides - 716.1 Information Theory and Signal ProcessingInformation Theory and Signal Processing - 921.1 AlgebraAlgebra
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Superpixel Optimization Using Higher Order Energy
Peng, Jianteng1; Shen, Jianbing1; Yao, Angela2; Li, Xuelong3 Source: IEEE Transactions on Circuits and Systems for Video Technology, v 26, n 5, p 917-927, May 2016
; ISSN: 10518215; DOI: 10.1109/TCSVT.2015.2430631; Article number: 7103037;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 Beijing Laboratory of Intelligent Information Technology, School of Computer Science, Beijing Institute of Technology, Beijing; 100081, China2 Institute of Computer Science II, University of Bonn, Bonn; 53113, Germany3 Center for OPTical IMagery Analysis and Learning, State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China
Abstract: A novel superpixel extraction algorithm using a higher order energy optimization framework is proposed in this paper. We first adopt the k-means clustering technique to quickly get an initial superpixel result. Then a higher order energy function is employed to optimize and refine these initial superpixels. We use a more general higher order energy function that includes a first-order data term, a second-order smoothness term, and a higher order term. The presegments are employed to provide the prior information of sufficient edges and segment regions for our higher order energy term. According to the texture measurement in different local regions, our algorithm adaptively computes the proper ratios of different energy terms to obtain a better superpixel performance. The experimental results demonstrate that our method using the higher order energy generates better results with well-aligned boundaries and homogeneous effects than the existing superpixel algorithms. © 2015 IEEE. (35 refs.)Main Heading: PixelsControlled terms: Algorithms - OptimizationUncontrolled terms: Extraction algorithms - Higher order terms - Higher-order - K-means clustering techniques - Prior information - Second orders - Super pixels - Texture measurementClassification Code: 921.5 Optimization TechniquesOptimization Techniques
Database: Compendex
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High accuracy three-dimensional attitude angle measuring device
Sun, Guo-Yan1, 2; Gao, Li-Min1; Bai, Jian-Ming1; Yang, Dong-Lai1; Pan, Liang1 Source: Guangxue Jingmi Gongcheng/Optics and Precision Engineering, v 24, n 5, p 963-970, May 1, 2016; Language: Chinese
; ISSN: 1004924X; DOI: 10.3788/OPE.20162405.0963;
Publisher: Chinese Academy of SciencesAuthor affiliation: 1 Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China2 University of Chinese Academy of Sciences, Beijing; 100049, China
Abstract: A high accuracy measuring device and corresponding measuring method for three-dimensional attitude angles (yaw, pitch and roll) were designed based on an autocollimator and a coordinate rotary transfer matrix. The working principle and structural composition were introduced. A three-dimensional attitude angle measuring model was established and the theory algorithm by coordinate rotation matrix was derived based on the principle of autocollimation angle measurement. Then, the optical system was designed according to the demand of the measurement system. A single Field Programming Gate Array (FPGA) was used to implement double CMOS image sensor imaging, spot identifying, subdivision positioning, three-dimensional attitude angle calculation and rapid communication with a USB. To ensure the unity of the actual equipment parameter and design data, a high precision calibration method was researched for the three-dimensional attitude angle measuring device. Finally, three-dimensional attitude angles were tested to verify this measuring device, and the degrees and the factors affecting the angle measuring accuracy were analyzed as well. Calibration and experiment measurement results indicate that the measuring precisions of the yaw, pitch and roll angles for the measuring device are 2.2″, 2.5″ and 7.8″ respectively in view field of ±20'. It shows that the three-dimensional attitude angle measuring device has higher precision, simpler structure as well as stronger stabilization, and can be widely applied to engineering practices. © 2016, Science Press. All right reserved. (14 refs.)Main Heading: Three dimensional computer graphicsControlled terms: Angle measurement - Calibration - CMOS integrated circuits - Field programmable gate arrays (FPGA) - Optical systems - Precision engineering - Transfer matrix methodUncontrolled terms: Angle measuring - Autocollimators - Pitch angle - Roll angle - Yaw anglesClassification Code: 714.2 Semiconductor Devices and Integrated CircuitsSemiconductor Devices and Integrated Circuits - 721.2 Logic ElementsLogic Elements - 723.2 Data Processing and Image ProcessingData Processing and Image Processing - 741.3 Optical Devices and SystemsOptical Devices and Systems - 921 MathematicsMathematics - 943.2 Mechanical Variables MeasurementsMechanical Variables Measurements
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Optical waveguides in magneto-optical glasses fabricated by proton implantation
Liu, Chun-Xiao1; Li, Yu-Wen1; Zheng, Rui-Lin1; Fu, Li-Li2; Zhang, Liao-Lin1; Guo, Hai-Tao3; Zhou, Zhi-Guang3; Li, Wei-Nan3; Lin, She-Bao4; Wei, Wei1 Source: Optics and Laser Technology, v 85, p 55-59, November 1, 2016
; ISSN: 00303992; DOI: 10.1016/j.optlastec.2016.05.008;
Publisher: Elsevier LtdAuthor affiliation: 1 School of Optoelectronic Engineering, Nanjing University of Posts and Telecommunications, Nanjing; 210023, China2 College of Electronic Science and Engineering, Nanjing University of Posts and Telecommunications, Nanjing; 210023, China3 State Key Laboratory of Transient Optics and Photonics, Xian Institute of Optics and Precision Mechanics, Chinese Academy of Sciences (CAS), Xian; 710119, China4 Institute of Physics and Optoelectronics Technology, Baoji University of Arts and Sciences, Baoji; 721007, China
Abstract: Planar waveguides in magneto-optical glasses (Tb3+-doped aluminum borosilicate glasses) have been produced by a 550-keV proton implantation at a dose of 4.0×1016ions/cm2for the first time to our knowledge. After annealing at 260 °C for 1.0 h, the dark-mode spectra and near-field intensity distributions are measured by the prism-coupling and end-face coupling methods. The damage profile, refractive index distribution and light propagation mode of the planar waveguide are numerically calculated by SRIM 2010, RCM and FD-BPM, respectively. The effects of implantation on the structural and optical properties are investigated by Raman and absorption spectra. It suggests that the proton-implanted Tb3+-doped aluminum borosilicate glass waveguide is a good candidate for a waveguide isolator in optical fiber communication and all-optical communication. © 2016 Elsevier Ltd All rights reserved. (25 refs.)Main Heading: Borosilicate glassControlled terms: Aluminum - Beam propagation method - Ion implantation - Light propagation - Optical communication - Optical fiber communication - Optical fiber fabrication - Optical fibers - Optical glass - Optical properties - Optical waveguides - Planar waveguides - Refractive index - WaveguidesUncontrolled terms: All-optical communication - Coupling methods - Magneto-optical - Near-field intensity - Proton implantation - Proton implanted - Refractive-index distribution - Structural and optical propertiesClassification Code: 541.1 AluminumAluminum - 711 Electromagnetic WavesElectromagnetic Waves - 714.3 WaveguidesWaveguides - 717.1 Optical Communication SystemsOptical Communication Systems - 741 Light, Optics and Optical DevicesLight, Optics and Optical Devices - 812.3 GlassGlass - 921 MathematicsMathematics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Ytterbium-doped double-cladding fiber with 3.5 kW output power, fabricated by chelate gas phase deposition technique
Hou, Chaoqi1; Zhu, Yonggang1; Zheng, Jinkun1; Li, Gang1; Li, Chao1; Gao, Song1; Gao, Qi1; Zhang, Lihua1; Chang, Chang1; Zhao, Wei1; Li, Weinan1; Zhao, Baoyin1 Source: Optical Materials Express, v 6, n 4, p 979-985, April 1, 2016; E-ISSN: 21593930; DOI: 10.1364/OME.6.000979;
Publisher: OSA - The Optical SocietyAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Science (CAS), Xi'an; 710119, China
Abstract: A ytterbium-doped double-cladding fiber was successfully fabricated by a chelate gas phase deposited technique. The measurement results of dopant concentration distribution and refractive index of preform indicate that radial and longitudinal homogeneity could be controlled perfectly with this technique. The absorption coefficients of fiber are 0.39 dB/m at 915nm and 1.02 dB/m at 976nm respectively. Using this fiber as the laser amplifier stage, 3592W output power at 1080nm with 72.5% slope efficiency was obtained with end-pump technique, which is close to the test results of Nufern commercial fiber. The results demonstrate that the chelate gas phase deposition technique is a relatively promising technique for high quality gain fiber fabrication. © 2016 Optical Society of America. (21 refs.)Main Heading: Fiber amplifiersControlled terms: Chelation - Cladding (coating) - Deposition - Doping (additives) - Fabrication - Fibers - Gases - Pumping (laser) - Refractive index - YtterbiumUncontrolled terms: Absorption co-efficient - Dopant concentrations - Double cladding fiber - Gas-phase deposition techniques - Laser amplifiers - Output power - Slope efficiencies - Ytterbium-dopedClassification Code: 547.2 Rare Earth MetalsRare Earth Metals - 741.1 Light/OpticsLight/Optics - 744.1 Lasers, GeneralLasers, General - 744.4 Solid State LasersSolid State Lasers - 802.2 Chemical ReactionsChemical Reactions - 802.3 Chemical OperationsChemical Operations
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Intra-hour cloud movement detection for solar forecasts based on ground imaging system
Jiang, Baotan1, 2, 3; Pan, Zhibin1; Qiu, Yuehong2; Chen, Zhi2; Yao, Dalei2; Bu, Fan2 Source: Optik, v 127, n 19, p 7803-7808, October 1, 2016
; ISSN: 00304026; DOI: 10.1016/j.ijleo.2016.05.126;
Publisher: Elsevier GmbHAuthor affiliation: 1 Xi' An Jiaotong University, Xi'an; 710049, China2 Xi'An Institute of Optics and Precision Mechanics of CAS, Xi'an; 710119, China3 University of Chinese Academy of Sciences, Beijing; 10039, China
Abstract: The penetration of solar energy continues to rise and becomes a central piece of the global energy mix. Thus, considering ways for more efficiently operated power systems to accommodate significant amounts of such a variable resource will be increasingly important. Improvements in solar forecasting methods and techniques will clearly be relevant. In addition to season and irradiation angle, the most important factor of influencing solar energy output is the effect of cloud movement on solar irradiation shadow on solar plate. This paper briefly analyzes the advantages and disadvantages of various moving target algorithms, and compares the typical feature matching algorithm (block motion estimation algorithm) and optical flow algorithm (CLG algorithm) against the collected cloud movement image sequence. The result shows that optical flow algorithm (CLG algorithm) is applied to cloud movement image. The calculation is very fast, with an accuracy above 96%. A comparison with CLG algorithm shows that direction and speed accuracy of block motion estimation algorithm based on hexagonal search pattern is 0.79 and 0.47, respectively. © 2016 Elsevier GmbH. (21 refs.)Main Heading: Motion estimationControlled terms: Algorithms - Forecasting - Image matching - Irradiation - Optical flows - Solar energy - Solar power generationUncontrolled terms: Block motion estimation - Cloud movements - Feature matching algorithms - Hexagon - Optical flow algorithm - Search patterns - Solar forecasting - Solar irradiationClassification Code: 615.2 Solar PowerSolar Power - 657.1 Solar Energy and PhenomenaSolar Energy and Phenomena - 741.1 Light/OpticsLight/Optics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Point cloud boundary detection in preprocessor of optical-mechanical integrated simulation
Xu, Guangzhou1, 2; Ruan, Ping1 Source: Hongwai yu Jiguang Gongcheng/Infrared and Laser Engineering, v 45, n 4, April 25, 2016; Language: Chinese
; ISSN: 10072276; DOI: 10.3788/IRLA201645.0428001; Article number: 0428001;
Publisher: Chinese Society of AstronauticsAuthor affiliation: 1 Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China2 University of Chinese Academy of Sciences, Beijing; 100049, China
Abstract: To resolve the data processing problem of point cloud for optical surface in general interface of optical-mechanical integrated simulation, the surface data processing method based on point cloud boundary detection was presented. First, the surface data preprocessing method in integrated simulation was discussed and effect of boundary detection in surface preprocessing data was also referred. Then, boundary detection algorithm referring to several techniques was researched including the data organization of point cloud, the small tangential plane fitting algorithm of the K-nearest neighbor node and the judgment of boundary node. Based on the research of point cloud boundary detection algorithm, the primary data structure and the program realization was discussed and by the extraction of demonstrated surface point cloud, the algorithm of boundary detection was proved to be right and effective. The algorithm of boundary detection provides the new technical reference for data process of optical surface. © 2016, Editorial Board of Journal of Infrared and Laser Engineering. All right reserved. (9 refs.)Main Heading: Data handlingControlled terms: Algorithms - Image segmentation - Motion compensation - Nearest neighbor search - Signal detectionUncontrolled terms: Boundary detection - Boundary detection algorithms - Data organization - Integrated simulations - K-nearest neighbors - Point cloud - Preprocessor - Processing problemsClassification Code: 716.1 Information Theory and Signal ProcessingInformation Theory and Signal Processing - 723.2 Data Processing and Image ProcessingData Processing and Image Processing - 921.5 Optimization TechniquesOptimization Techniques
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Research progress of new space mirror materials
Wang, Yongjie1, 2; Xie, Yongjie1; Ma, Zhen1; Xu, Liang1; Ding, Jiaoteng1 Source: Cailiao Daobao/Materials Review, v 30, n 4, p 143-147 and 153, April 10, 2016; Language: Chinese
; ISSN: 1005023X; DOI: 10.11896/j.issn.1005-023X.2016.07.025;
Publisher: Cailiao Daobaoshe/ Materials ReviewAuthor affiliation: 1 Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China2 State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi'an; 710072, China
Abstract: Traditional mirror materials cannot meet the lager and lighter requirement of the future space reflectors. Carbon fiber-reinforced composites will become significant ones in the space mirror field due to their outstanding properties. In this paper, three composites (C/SiC, CFRP and C/C composites) are introduced, which have great potential on space mirrors application. The properties, fabrication methods, application status, technological constraints of these composites are also described. Finally, the corresponding prospective application and development of carbon reinforced composites are anticipated. © 2016, Materials Review Magazine. All right reserved. (42 refs.)Main Heading: MirrorsControlled terms: Carbon carbon composites - Fiber reinforced plastics - Reflection - ReinforcementUncontrolled terms: Application status - Carbon fiber reinforced composite - Large aperture - Lightweight - Prospective applications - Reinforced composites - Space reflectors - Technological constraintsClassification Code: 415.4 Structural Materials Other Than Metal, Plastics or WoodStructural Materials Other Than Metal, Plastics or Wood - 741.3 Optical Devices and SystemsOptical Devices and Systems - 951 Materials ScienceMaterials Science
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Experiment research and analysis of spectral prediction on soil leaking oil content
Yu, Lu1, 2, 3; Liu, Xue-Bin1; Liu, Gui-Zhong2; Feng, Yu-Tao1; Wang, Shuang1; Yu, Tao1 Source: Guang Pu Xue Yu Guang Pu Fen Xi/Spectroscopy and Spectral Analysis, v 36, n 4, p 1116-1120, April 1, 2016; Language: Chinese
; ISSN: 10000593; DOI: 10.3964/j.issn.1000-0593(2016)04-1116-05;
Publisher: Science PressAuthor affiliation: 1 Laboratory of Spectral Imaging Technique, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China2 School of Electronic and Information Engineering, Xi'an Jiaotong University, Xi'an; 710049, China3 University of Chinese Academy of Sciences, Beijing; 100049, China
Abstract: The spectral analysis method was applied experimentally to extract the spectral indices, measure and analyze the spectral characteristics and their difference of the mixture which are composed in soil in Central Shaanxi Plain and the diesel and motor oil respectively, aiming to provide solutions to practical difficulties in detecting, analyzing the spectral characteristics and difference between the soil leaking with equal content diesel and motor oil and predicting the leaking content of diesel in the soil. The spectral response curves of the soil leaking with different oil respectively and the soil leaking with diesel with different content were collected. Then the spectral prediction model for the leaking content of diesel in the soil was built based on the reflectance characteristics. The coefficient of the detection (R2) was introduced to evaluate the stability of the built model, and the parameter root mean squared error (RMSE) was introduced to estimate the precision and the predictability of the model built in this work. It is demonstrated that: (1) The reflectance of soil leaking with diesel is less than that of the equal content motor oil. And there is a double absorption trough of the reflectance curve of both soil leaking with diesel and motor oil at 1740 and 2328 nm. The spectral absorption indices and absorption depth of the soil leaking with diesel keep less than the equal content motor oil. (2) The built spectral prediction model for the leaking content of diesel in the soil demonstrates good stability with the coefficient of determination at R2=0.854, and performs favorable predictability (Root-Mean-Square Error, RMSE=0.016), which can benefit the effective prediction and quick estimation methods of the leaking content of diesel in the soil, enrich and progress the experimental method and theoretical research work of spectral prediction on soil leaking oil content and promote the application of remote sensing in safety production and environmental protection. © 2016, Peking University Press. All right reserved. (12 refs.)Main Heading: SoilsControlled terms: Forecasting - Lubricating oils - Mean square error - Reflection - Remote sensing - Spectrum analysisUncontrolled terms: Coefficient of determination - Oil leaking - Prediction model - Reflectance characteristics - Root mean squared errors - Spectral - Spectral absorption indices - Spectral prediction modelClassification Code: 483.1 Soils and Soil MechanicsSoils and Soil Mechanics - 607.1 LubricantsLubricants - 922.2 Mathematical StatisticsMathematical Statistics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Image dehazing technique based on polarimetric spectral analysis
Xia, Pu1, 2; Liu, Xuebin1 Source: Optik, v 127, n 18, p 7350-7358, September 1, 2016
; ISSN: 00304026; DOI: 10.1016/j.ijleo.2016.05.071;
Publisher: Elsevier GmbHAuthor affiliation: 1 Key Laboratory of Spectral Imaging Technology, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China2 University of Chinese Academy of Sciences, Beijing; 100049, China
Abstract: Image took under hazy weather suffers from poor contrast and resolution, the haze particles will attenuate the light reflected by the targets and add unwanted scattering light. Based on the fact that the target reflection and scattering light have different polarimetric characteristics, light's power to penetrate the haze particles is linked with wavelength, this paper combines the polarimetric dehazing technique with spectral analysis, firstly proposed the polarimetric spectral dehazing method. A polarimetric spectral imager is used to obtain data under a continuously changing weather circle, the dehazing result is analyzed under five different spectral channels of 451.4 nm, 551.2 nm, 650.9 nm, 750.7 nm and 850.5 nm. The results show that our method can effectively recover the haze degenerated image under visible and infrared channels, the restoration quality of detailed information of the near-field and the far-field targets are in varying degrees under different channels. The dehazing process can enhance the image contrast by 1.68-3.64 times under different wavelengths. Two correction factors, which regularity is given for particle use, are introduced to revise an image restoration result. © 2016 The Authors. Published by Elsevier GmbH. (14 refs.)Main Heading: DemulsificationControlled terms: Image analysis - Image reconstruction - Light scattering - Polarimeters - Restoration - Spectroscopy - Spectrum analysisUncontrolled terms: Atmospheric scattering - Correction factors - Haze removal - Image correction - Infrared channel - Restoration quality - Scattering light - Spectral channelsClassification Code: 741.1 Light/OpticsLight/Optics - 802.3 Chemical OperationsChemical Operations - 941.3 Optical InstrumentsOptical Instruments
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Image plane intersection interference imaging spectrometer based on Mach-Zehnder
Xiao, Xiangguo1, 2; Zhang, Shuanmin1; Chen, Xiuping1 Source: Hongwai yu Jiguang Gongcheng/Infrared and Laser Engineering, v 45, n 5, May 25, 2016; Language: Chinese
; ISSN: 10072276; DOI: 10.3788/IRLA201645.0524001; Article number: 0524001;
Publisher: Chinese Society of AstronauticsAuthor affiliation: 1 Xi'an Institute of Applied Optics, Xi'an; 710065, China2 Department of Precision Instrument, Tsinghua University, Beijing; 100084, China
Abstract: Image plane intersection interference imaging spectroscopy is a kind of compact imaging spectrometer technology, which has characteristics of small volume and light weight, and is used for small satellite remote sensing mission or airborne photoelectric reconnaissance. Image plane intersection interference imaging spectroscopy was studied. The design scheme of angle shear beam splitter was given based on Mach-Zehnder composed of prisms. Work principle and design method were discussed in detail. The angle shear of beam splitter based on Mach-Zehnder was analyzed under certain spectrum resolution combined design example. At same time, object characteristics of image plane intersection interference imaging system was studied. Image plane intersection interference imaging spectroscopy technology was verified in experiment. © 2016, Editorial Board of Journal of Infrared and Laser Engineering. All right reserved. (13 refs.)Main Heading: SpectrometersControlled terms: Fourier transforms - Optical instruments - Prisms - Remote sensingUncontrolled terms: Combined design - Image plane - Imaging spectrometers - Interference imaging - Object characteristics - Shear beams - Small-satellite - Spectrum resolutionClassification Code: 741.3 Optical Devices and SystemsOptical Devices and Systems - 921.3 Mathematical TransformationsMathematical Transformations - 941.3 Optical InstrumentsOptical Instruments
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Detection of hyperspectral small targets based on projection pursuit optimized by bee colony
Wu, Yiquan1, 2; Zhou, Yang1; Long, Yunlin1 Source: Yi Qi Yi Biao Xue Bao/Chinese Journal of Scientific Instrument, v 37, n 6, p 1347-1355, June 1, 2016; Language: Chinese
; ISSN: 02543087;
Publisher: Science PressAuthor affiliation: 1 College of Electronic and Information Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing; 211106, China2 Key Laboratory of Spectral Imaging Technology, CAS, Xi'an Institute of Optics and Precision Mechanics, Xi'an; 710119, China
Abstract: In order to further improve the operation speed and reduce the false alarm rate of the unsupervised detection method for small targets in hyperspectral remote sensing images, a detection method based on the projection pursuit (PP) optimized by improved artificial bee colony (ABC) optimization algorithm and K-nearest neighbor (KNN) is proposed in this paper. Firstly, the kernel principal component analysis (KPCA) method is adopted to perform the dimension reduction of the original hyperspectral remote sensing images. Then, the method jointly defining the kurtosis and skewness according to the neighborhood pixels is proposed, the combination of the kurtosis and skewness is taken as the projection index. The improved artificial bee colony algorithm is taken as the optimization algorithm. The projection pursuit is used to obtain the projection images layer by layer from the low dimensional hyperspectral remote sensing images, and the small targets are extracted according to the histogram of these projection images. Finally, the linear discriminant analysis (LDA) is used to extract the features of the pixels, and the weighted K-nearest neighbor method is used to purify the preliminary detection results of the small targets. A large number of experiment results show that compared with the RX method, independent component analysis (ICA) method and the projection pursuit method based on chaotic particle swarm optimization (CPSO), the proposed method not only can detect the small targets in hyperspectral remote sensing image accurately, but also has faster operation speed. © 2016, Science Press. All right reserved. (16 refs.)Main Heading: Radar target recognitionControlled terms: Algorithms - Discriminant analysis - Evolutionary algorithms - Higher order statistics - Image analysis - Image processing - Image reconstruction - Independent component analysis - Motion compensation - Nearest neighbor search - Optimization - Particle swarm optimization (PSO) - Pixels - Principal component analysis - Remote sensing - Spectroscopy - Statistical methodsUncontrolled terms: Bee colony optimizations - Hyper-spectral images - K-nearest neighbors - Projection pursuits - Small target detectionClassification Code: 716.2 Radar Systems and EquipmentRadar Systems and Equipment - 921.5 Optimization TechniquesOptimization Techniques - 922 Statistical MethodsStatistical Methods - 922.2 Mathematical StatisticsMathematical Statistics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Modified photon counting communication method for underwater application
Han, Biao1, 2; Zhao, Wei1; Wang, Wei1; Su, Yulong1; Liu, Jifang3 Source: Guangxue Xuebao/Acta Optica Sinica, v 36, n 8, August 10, 2016; Language: Chinese
; ISSN: 02532239; DOI: 10.3788/AOS201636.0806004; Article number: 0806004;
Publisher: Chinese Optical SocietyAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; Shaanxi; 710119, China2 University of Chinese Academy of Sciences, Beijing; 100049, China3 School of Physics and Optoelectronic Engineering, Xidian University, Xi'an; Shaanxi; 710071, China
Abstract: Underwater laser communication is influenced by the absorption and scattering of water, which causes severe signal energy attenuation during propagation. Laser communication based on the photon counting is considered as an effective way to resist signal loss and increase communication distance because of its ultra-high detection sensitivity. However, since communication data recovery is usually realized by detecting electrical pulse at the output of single photon detector directly in traditional photon counting communication, the communication bit error rate would be easily influenced by background light noise. In this paper, an improved method is proposed and studied to solve this problem. In our approach, the photons arrived at the communication receiver are converted into electrical pulses by single photon detector first. Then, communication data is recovered through counting the electrical pulse number on unit time. The experimental result shows that detection sensitivity of 84.24 bit-1can be realized by the proposed method, when the communication wavelength is 532 nm, the communication rate is 50 kb/s, and the signal to noise ratio is 5.14.The novel approach proposed in this paper provides a new technical idea for high-sensitivity underwater laser communication. © 2016, Chinese Lasers Press. All right reserved. (15 refs.)Main Heading: Optical communicationControlled terms: Avalanche photodiodes - Bit error rate - Particle beams - Photodetectors - Photons - Signal to noise ratio - Underwater acoustics - Water absorptionUncontrolled terms: Absorption and scatterings - Communication receivers - Communication wavelengths - Photon counting - Single-photon detectors - Underwater communication - Underwater laser communications - Wireless optical communicationClassification Code: 716.1 Information Theory and Signal ProcessingInformation Theory and Signal Processing - 717.1 Optical Communication SystemsOptical Communication Systems - 723.1 Computer ProgrammingComputer Programming - 751.1 Acoustic WavesAcoustic Waves - 802.3 Chemical OperationsChemical Operations - 931.3 Atomic and Molecular PhysicsAtomic and Molecular Physics - 932.1 High Energy PhysicsHigh Energy Physics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Research on broadband spectral imaging spectrometer based on CDP
Zhang, Zhou-Feng1, 2, 3; Hu, Bing-Liang1; Yin, Qin-Ye2; Gao, Xiao-Hui1 Source: Guang Pu Xue Yu Guang Pu Fen Xi/Spectroscopy and Spectral Analysis, v 36, n 7, p 2284-2286, July 1, 2016; Language: Chinese
; ISSN: 10000593; DOI: 10.3964/j.issn.1000-0593(2016)07-2284-03;
Publisher: Science PressAuthor affiliation: 1 Key Laboratory of Spectral Imaging Technique, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China2 School of Electronic and Information Engineering, Xi'an Jiaotong University, Xi'an; 710049, China3 University of Chinese Academy of Sciences, Beijing; 100049, China
Abstract: In order to satisfy the application requirements of real-time spectral imaging for moving targets, we design a static, snapshot imaging spectrometer based on a CDP(crossed dispersion prism). The spectral imaging principle is studied, and an optical system of broadband spectral imaging spectrometer is designed according to this principle. Imaging spectrometer consists of a CDP, an imaging lens and a detector, with ±2°field of view, spectral coverage from 0.6 to 5.0 μm, The results show that this instrument has a better ability to detect spectral from 0.6 to 5.0 μm while the average spectral resolution is 20 nm. The technology for dynamic target real-time spectral imaging provides a new technical way. It has a great potential for detecting, locating and identifying unknown energetic events in real-time. © 2016, Peking University Press. All right reserved. (10 refs.)Main Heading: SpectrometersControlled terms: Optical systems - SpectroscopyUncontrolled terms: Application requirements - Dynamic target - Imaging spectrometers - Moving targets - Real-time detection - Spectral coverage - Spectral detection - Spectral imagingClassification Code: 741.3 Optical Devices and SystemsOptical Devices and Systems
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Characteristics of the orbital rotation in dual-beam fiber-optic trap with transverse offset
Chen, Xinlin1; Xiao, Guangzong1, 2; Yang, Kaiyong1; Xiong, Wei1; Luo, Hui1 Source: Optics Express, v 24, n 15, p 16952-16960, July 25, 2016; E-ISSN: 10944087; DOI: 10.1364/OE.24.016961;
Publisher: OSA - The Optical SocietyAuthor affiliation: 1 College of Optoelectronic Science and Engineering, National University of Defense Technology, Changsha; 410073, China2 State Key Laboratory of Transient Optics and Photonic, Chinese Academy of Sciences, Xian; 710068, China
Abstract: The orbital rotation is an important type of motion of trapped particles apart from translation and spin rotation. It could be realized by introducing a transverse offset to the dual-beam fiber-optic trap. The characteristics (e.g. rotation perimeter and frequency) of the orbital rotation have been analyzed in this article. We demonstrate the influences of offset distance, beam waist separation distance, light power, and radius of the microsphere by both experimental and numerical work. The experiment results, i.e. orbital rotation perimeter and frequency as functions of these parameters, are consistent with the theoretical model in the present work. The orbital rotation amplitude and frequency could be exactly controlled by varying these parameters. This controllable orbital rotation can be easily applied to the area where microfluidic mixing is required. ©2016 Optical Society of America. (27 refs.)Main Heading: RotationControlled terms: Fiber optics - Spinning (fibers)Uncontrolled terms: Microfluidic mixing - Offset distances - Orbital rotations - Separation distances - Spin-rotations - Theoretical modeling - Transverse offset - Trapped particleClassification Code: 741.1.2 Fiber OpticsFiber Optics - 819.3 Fiber Chemistry and ProcessingFiber Chemistry and Processing - 931.1 MechanicsMechanics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


High-peak-power sub-nanosecond intracavity KTiOPO4 optical parametric oscillator pumped by a dual-loss modulated laser with acousto-optic modulator and single-walled carbon nanotube
Qiao, Junpeng1; Zhao, Shengzhi1; Yang, Kejian1; Zhao, Jia1; Li, Guiqiu1; Li, Dechun1; Li, Tao1; Qiao, Wenchao1; Lu, Jianren1; Wang, Yonggang2; Chu, Hongwei1; Luan, Chao1 Source: Applied Physics Express, v 9, n 8, August 2016
; ISSN: 18820778, E-ISSN: 18820786; DOI: 10.7567/APEX.9.082701; Article number: 082701;
Publisher: Japan Society of Applied PhysicsAuthor affiliation: 1 School of Information Science and Engineering, Shandong University, Jinan; 250100, China2 State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China
Abstract: A high-peak-power low-repetition-rate sub-nanosecond intracavity KTiOPO4 (KTP) optical parametric oscillator (OPO) pumped by a doubly Q-switched and mode-locked (QML) YVO4/Nd:YVO4 laser with an acousto-optic modulator (AOM) and a single-walled carbon nanotube saturable absorber (SWCNT-SA) has been demonstrated. A maximum output power of 373mW at a signal wavelength of 1570nm was obtained. The smallest pulse width, highest pulse energy, and greatest peak power of mode-locking pulses were estimated to be 119 ps, 124 μJ, and 1.04MW, respectively, under a maximum incident pump power of 8.3W and an AOM repetition rate of 2 kHz. This OPO operation paves a simple way to produce eye-safe laser sources at 1570nm with low repetition rates, small pulse widths, and high peak powers. © 2016 The Japan Society of Applied Physics. (23 refs.)Main Heading: Parametric oscillatorsControlled terms: Carbon nanotubes - Light modulators - Locks (fasteners) - Nanotubes - Optical parametric oscillators - Optical pumping - Optically pumped lasers - Photomasks - Pulse repetition rate - Pumping (laser) - Q switched lasers - Saturable absorbers - Single-walled carbon nanotubes (SWCN) - YarnUncontrolled terms: Acousto-optic modulator - Dual-loss-modulated - Eye-safe lasers - Incident pump power - Low repetition rate - Maximum output power - Signal wavelength - Single-walled carbon nanotube saturable absorbersClassification Code: 713.2 OscillatorsOscillators - 744.1 Lasers, GeneralLasers, General - 745.1 PrintingPrinting - 761 NanotechnologyNanotechnology - 819.4 Fiber ProductsFiber Products
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Recent Advances in Cloud Radio Access Networks: System Architectures, Key Techniques, and Open Issues
Peng, Mugen1; Sun, Yaohua1; Li, Xuelong2; Mao, Zhendong1; Wang, Chonggang3 Source: IEEE Communications Surveys and Tutorials, v 18, n 3, p 2282-2308, Third Quarter 2016; E-ISSN: 1553877X; DOI: 10.1109/COMST.2016.2548658; Article number: 7444125;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 Key Laboratory of Universal Wireless Communications for Ministry of Education, Beijing University of Posts and Telecommunications, Beijing; 100876, China2 Center for OPTical IMagery Analysis and Learning (OPTIMAL), State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics, Xi'an; 710119, China3 InterDigital Communications, King of Prussia; PA; 19406, United States
Abstract: As a promising paradigm to reduce both capital and operating expenditures, the cloud radio access network (C-RAN) has been shown to provide high spectral efficiency and energy efficiency. Motivated by its significant theoretical performance gains and potential advantages, C-RANs have been advocated by both the industry and research community. This paper comprehensively surveys the recent advances of C-RANs, including system architectures, key techniques, and open issues. The system architectures with different functional splits and the corresponding characteristics are comprehensively summarized and discussed. The state-of-The-Art key techniques in C-RANs are classified as: The fronthaul compression, large-scale collaborative processing, and channel estimation in the physical layer; and the radio resource allocation and optimization in the upper layer. Additionally, given the extensiveness of the research area, open issues, and challenges are presented to spur future investigations, in which the involvement of edge cache, big data mining, social-Aware device-To-device, cognitive radio, software defined network, and physical layer security for C-RANs are discussed, and the progress of testbed development and trial test is introduced as well. © 1998-2012 IEEE. (151 refs.)Main Heading: C (programming language)Controlled terms: Big data - Channel estimation - Cognitive radio - Computer architecture - Data mining - Energy efficiency - Network architecture - Network layers - Radio - Resource allocation - Software testingUncontrolled terms: High spectral efficiency - Physical layer security - Radio access networks - Radio resource allocation - Research communities - State of the art - System architectures - Theoretical performanceClassification Code: 525.2 Energy ConservationEnergy Conservation - 716.3 Radio Systems and EquipmentRadio Systems and Equipment - 723 Computer Software, Data Handling and ApplicationsComputer Software, Data Handling and Applications - 912.2 ManagementManagement
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Pedestrian detection inspired by appearance constancy and shape symmetry
Cao, Jiale1; Pang, Yanwei1; Li, Xuelong2 Source: Proceedings of the IEEE Computer Society Conference on Computer Vision and Pattern Recognition, v 2016-January, p 1316-1324, 2016, 2016 IEEE Conference on Computer Vision and Pattern Recognition, CVPR 2016
; ISSN: 10636919; ISBN-13: 9781467388511; Conference: 2016 IEEE Conference on Computer Vision and Pattern Recognition, CVPR 2016, June 26, 2016 - July 1, 2016;
Publisher: IEEE Computer SocietyAuthor affiliation: 1 School of Electronic Information Engineering, Tianjin University, China2 Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, China
Abstract: The discrimination and simplicity of features are very important for effective and efficient pedestrian detection. However, most state-of-the-art methods are unable to achieve good tradeoff between accuracy and efficiency. Inspired by some simple inherent attributes of pedestrians (i.e., appearance constancy and shape symmetry), we propose two new types of non-neighboring features (NNF): side-inner difference features (SIDF) and symmetrical similarity features (SSF). SIDF can characterize the difference between the background and pedestrian and the difference between the pedestrian contour and its inner part. SSF can capture the symmetrical similarity of pedestrian shape. However, it's difficult for neighboring features to have such above characterization abilities. Finally, we propose to combine both non-neighboring and neighboring features for pedestrian detection. It's found that nonneighboring features can further decrease the average miss rate by 4.44%. Experimental results on INRIA and Caltech pedestrian datasets demonstrate the effectiveness and efficiency of the proposed method. Compared to the state-ofthe-art methods without using CNN, our method achieves the best detection performance on Caltech, outperforming the second best method (i.e., Checkerboards) by 1.63%. (37 refs.)Main Heading: Feature extractionControlled terms: Computer vision - Efficiency - Object detection - Pattern recognitionUncontrolled terms: Art methods - Caltech - Detection performance - Effectiveness and efficiencies - Miss-rate - Pedestrian detection - Shape symmetry - State-of-the-art methodsClassification Code: 723.2 Data Processing and Image ProcessingData Processing and Image Processing - 723.5 Computer ApplicationsComputer Applications - 913.1 Production EngineeringProduction Engineering
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Microwave and RF applications for micro-resonator based frequency combs
Nguyen, Thach G.1; Shoeiby, Mehrdad1; Ferrera, Marcello2; Pasquazi, Alessia3; Peccianti, Marco3; Chu, Sai T.4; Little, Brent E.5; Morandotti, Roberto6; Mitchell, Arnan1; Moss, David J.7 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 9750, 2016, Integrated Optics: Devices, Materials, and Technologies XX
; ISSN: 0277786X, E-ISSN: 1996756X; ISBN-13: 9781628419856; DOI: 10.1117/12.2218883; Article number: 97500H; Conference: Integrated Optics: Devices, Materials, and Technologies XX, February 15, 2016 - February 17, 2016; Sponsor: The Society of Photo-Optical Instrumentation Engineers (SPIE);
Publisher: SPIEAuthor affiliation: 1 Schoof of Electrical and Computer Engineering, RMIT University, Melbourne; VIC; 3001, Australia2 School of Engineering and Physical Sciences, Heriot-Watt University, David Brewster Building, Edinburgh; EH14 4AS, United Kingdom3 Department of Physics and Astronomy, University of Sussex, Falmer, Brighton; BN1 9RH, United Kingdom4 Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Hong Kong, Hong Kong5 Xi'An Institute of Optics and Precision Mechanics of CAS, Xi'an, China6 INSR-Énergie,Matériaux et Télécommunications, 1650 Blvd Lionel Boulet, Varennes; QC; J3X1S2, Canada7 Center for Micro-Photonics, Swinburne University of Technology, Melbourne; VIC, Australia
Abstract: Photonic integrated circuits that exploit nonlinear optics in order to generate and process signals all-optically have achieved performance far superior to that possible electronically - particularly with respect to speed. We review the recent achievements based in new CMOS-compatible platforms that are better suited than SOI for nonlinear optics, focusing on radio frequency (RF) and microwave based applications that exploit micro-resonator based frequency combs. We highlight their potential as well as the challenges to achieving practical solutions for many key applications. These material systems have opened up many new capabilities such as on-chip optical frequency comb generation and ultrafast optical pulse generation and measurement. We review recent work on a photonic RF Hilbert transformer for broadband microwave in-phase and quadrature-phase generation based on an integrated frequency optical comb. The comb is generated using a nonlinear microring resonator based on a CMOS compatible, high-index contrast, doped-silica glass platform. The high quality and large frequency spacing of the comb enables filters with up to 20 taps, allowing us to demonstrate a quadrature filter with more than a 5-octave (3 dB) bandwidth and an almost uniform phase response. © 2016 SPIE. (68 refs.)Main Heading: Microwave resonatorsControlled terms: CMOS integrated circuits - Crystal resonators - Integrated optics - Light pulse generators - Microelectromechanical devices - Nonlinear optics - Optical frequency conversion - Optical waveguides - Photonic devices - Photonics - Pulse generators - ResonatorsUncontrolled terms: High index contrast - Hilbert transformers - In-phase and quadrature-phase - Integrated optics materials - Optical frequency comb generation - Photonic integrated circuits - Silicon photonics - Ultrafast optical pulseClassification Code: 713.4 Pulse CircuitsPulse Circuits - 713.5 Electronic Circuits Other Than Amplifiers, Oscillators, Modulators, Limiters, Discriminators or MixersElectronic Circuits Other Than Amplifiers, Oscillators, Modulators, Limiters, Discriminators or Mixers - 714 Electronic Components and TubesElectronic Components and Tubes - 741 Light, Optics and Optical DevicesLight, Optics and Optical Devices
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Ultrafast optical beam deflection in a pump probe configuration
Liang, Lingliang1, 2, 3; Tian, Jinshou1; Wang, Tao1; Wu, Shengli3; Li, Fuli3; Wang, Junfeng1; Gao, Guilong1, 2, 3 Source: Chinese Physics B, v 25, n 9, September 2016
; ISSN: 16741056; DOI: 10.1088/1674-1056/25/9/090602; Article number: 090602;
Publisher: Institute of Physics PublishingAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China2 University of Chinese Academy of Sciences, Beijing; 100049, China3 Xi'An Jiaotong University, Xi'an; 710049, China
Abstract: Propagation of a signal beam in an AlGaAs/GaAs waveguide multiple-prism light deflector is theoretically investigated by solving the scalar Helmholtz equation to obtain the dependences of the temporal and spatial resolvable characteristics of the ultrafast deflector on the material dispersion of GaAs including group velocity dispersion and angular dispersion, interface reflection, and interface scattering of multiple-prism deflector. Furthermore, we experimentally confirm that, in this ultrafast beam deflection device, the deflecting angle of the signal light beam is linear with the pump fluence and the temporal resolution of the ultrafast deflection is 10 ps. Our results show that the improvement of the temporal and spatial resolvable performances is possible by properly choosing the structural parameters and enhancing the quality of the device. © 2016 Chinese Physical Society and IOP Publishing Ltd. (28 refs.)Main Heading: Deflection (structures)Controlled terms: Aluminum gallium arsenide - Dispersion (waves) - Group velocity dispersion - Interfaces (materials) - Optical instruments - Prisms - Probes - PumpsUncontrolled terms: Light deflectors - Material dispersions - Optical beam deflection - Pump probe - Pump-probe configuration - Temporal resolution - Ultra-fast - Ultrafast deflectorsClassification Code: 408.2 Structural Members and ShapesStructural Members and Shapes - 618.2 PumpsPumps - 712.1.2 Compound Semiconducting MaterialsCompound Semiconducting Materials - 741.3 Optical Devices and SystemsOptical Devices and Systems - 941.3 Optical InstrumentsOptical Instruments - 951 Materials ScienceMaterials Science
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Preface
Tan, Tieniu1; Li, Xuelong2; Chen, Xilin3; Zhou, Jie4; Yang, Jian5; Cheng, Hong6 Source: Communications in Computer and Information Science, v 662, 2016, Pattern Recognition - 7th Chinese Conference, CCPR 2016, Proceedings
; ISSN: 18650929; ISBN-13: 9789811030017; Conference: 7th Chinese Conference on Pattern Recognition, CCPR 2016, November 5, 2016 - November 7, 2016;
Publisher: Springer VerlagAuthor affiliation: 1 Chinese Academy of Sciences, Institute of Automation, Beijing, China2 Xi’an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi’an, China3 Chinese Academy of Sciences, Institute of Computing Technology, Beijing, China4 Tsinghua University, Beijing, China5 Nanjing University of Science and Technology, Nanjing, China6 University of Electronic Science University of Electronic Science, Chengdu; Sichuan, China
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Simulation of the effects of coated material SEY property on output electron energy distribution and gain of microchannel plates
Chen, Lin1, 2, 4; Wang, Xingchao3; Tian, Jinshou1, 5; Liu, Chunliang4; Liu, Hulin1; Chen, Ping1, 2; Wei, Yonglin1; Sai, Xiaofeng1; Sun, Jianning3; Si, Shuguang3; Wang, Xing1; Lu, Yu1; Tian, Liping1, 2; Hui, Dandan1, 2; Guo, Lehui1, 2 Source: Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, v 840, p 133-138, December 21, 2016
; ISSN: 01689002; DOI: 10.1016/j.nima.2016.10.014;
Publisher: Elsevier B.V.Author affiliation: 1 Key Laboratory of Ultra-fast Photoelectric Diagnostics Technology, Xi'an Institute of Optics and Precision Mechanics (XIOPM), Chinese Academy of Sciences (CAS), Xi'an; 710119, China2 Graduate School of Chinese Academy of Sciences (CAS), Beijing; 100049, China3 North Night Vision Technology (NNVT) Co., Ltd., Nanjing; 210110, China4 Xi'an Jiaotong University, Xi'an; 710049, China5 Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan; 030006, China
Abstract: To obtain a high spatial resolution of a image intensifier based on microchannel plate (MCP), the long tail in the exit energy distribution of the output electrons (EDOE) is undesirable. The existing solution is increasing the penetration depth of the MCP output electrode, which will result in a serious gain reduction. Coating the MCP output electrode with efficient secondary electron yield (SEY) materials is supposed to be an effective approach to suppress the unfavorable tail component in the EDOE without negative effects on the gain. In our work, a three-dimensional MCP single channel model is developed in CST STUDIO SUITE to systematically investigate the dependences of the EDOE and the gain on the SEY property of the coated material, based on the Finite Integral Technique and Monte Carlo method. The results show that besides the high SEY of the coated material, the low incident energy corresponding to the peak SEY is another essential element affecting the electron yield in the final stage of multiplication and suppressing the output energy spread. © 2016 Elsevier B.V. (22 refs.)Main Heading: Image storage tubesControlled terms: Coated materials - Electrodes - Electron emission - Electron energy levels - Electrons - Microchannels - Monte Carlo methods - Secondary emissionUncontrolled terms: EDOE - Electron energy distributions - Energy distributions - Finite integral techniques - Gain - High spatial resolution - Micro channel plate - Secondary electron yieldClassification Code: 714.1 Electron TubesElectron Tubes - 813 Coatings and FinishesCoatings and Finishes - 922.2 Mathematical StatisticsMathematical Statistics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Initial cumulative effects in femtosecond pulsed laser-induced periodic surface structures on bulk metallic glasses
Li, Chen1, 2, 3; Zhang, Hao1; Cheng, Guanghua2; Faure, Nicolas1; Jamon, Damien1; Colombier, Jean-Philippe1; Stoian, Razvan1 Source: Journal of Laser Micro Nanoengineering, v 11, n 3, p 357-365, 2016; E-ISSN: 18800688; DOI: 10.2961/jlmn.2016.03.0014;
Publisher: Japan Laser Processing SocietyAuthor affiliation: 1 Laboratoire Hubert Curien, UMR 5516 CNRS, Université de Lyon, Université Jean Monnet, Saint Etienne; 42000, France2 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, CAS, Xi'an, Shaanxi; 710119, China3 University of Chinese Academy of Science, Beijing; 10049, China
Abstract: We investigate initial cumulative irradiation effects leading to variable surface topographies and nanoscale roughness, and triggering eventually the formation of laser-induced periodic surface structures (LIPSS) on Zr-based bulk metallic glasses (Zr41.2Ti13.8Cu12.5Ni10Be25.5(at%)). We discuss interconnected aspects related to electronic excitation and optical transients, potential variations in the cartography of thermally-driven chemical modifications and topographical features assisting the surface coupling of the electromagnetic field. The transient optical properties of Zr-based BMG surfaces upon ultrafast irradiation, measured by a two-angle time-resolved single-pump double-probe ellipsometry method, show a remarkable constancy up to the point of optical damage and rapid gas-phase transition beyond. In intermediate and low exposure conditions, in the vicinity of the damage domain, multi-pulse incubation effects determine the appearance of nanoscale surface structures. The aspects discussed here involve primarily the progression of nanoscale structuring with an increasing number of fs laser pulses starting from a rough surface and evolving towards ordered corrugation. We emphasize the role of initial roughness in determining light coupling and the generation of regular stationary patterns of scattered light, localized energy absorption and spatially-variant ablation or modulated temperature-driven factors for surface relief. From a material perspective, energy dispersive X-ray spectrometry (EDX) analysis shows potential selective vaporization of light elements, leading to gradual compositional changes and proving a spatially-modulated temperature pattern. A formation scenario is proposed involving interference between the incident laser and scattered light potentially mediated by localized surface plasmons. Finite-difference time-domain (FDTD) simulations are applied to validate the mechanism, showing that LIPSS appear intrinsically related to the surface superposition of electromagnetic waves. (33 refs.)Main Heading: Pulsed lasersControlled terms: Chemical elements - Chemical modification - Electric excitation - Electromagnetic fields - Electromagnetic waves - Energy dispersive spectroscopy - Finite difference time domain method - Glass - Irradiation - Laser pulses - Light scattering - Maps - Metallic glass - Nanotechnology - Optical properties - Periodic structures - Surface roughness - Surface scattering - Surface structure - Time domain analysis - Ultrafast lasersUncontrolled terms: Energy dispersive X-ray spectrometry - Femtosecond pulsed laser - Finite-difference time-domain simulation - Laser-induced periodic surface structures - LIPSS - Localized surface plasmon - Ultrafast laser processing - Zr based bulk metallic glassClassification Code: 405.3 SurveyingSurveying - 531 Metallurgy and MetallographyMetallurgy and Metallography - 701 Electricity and MagnetismElectricity and Magnetism - 701.1 Electricity: Basic Concepts and PhenomenaElectricity: Basic Concepts and Phenomena - 711 Electromagnetic WavesElectromagnetic Waves - 741.1 Light/OpticsLight/Optics - 744.1 Lasers, GeneralLasers, General - 761 NanotechnologyNanotechnology - 804 Chemical Products GenerallyChemical Products Generally - 812.3 GlassGlass - 921 MathematicsMathematics - 931 Classical Physics; Quantum Theory; RelativityClassical Physics; Quantum Theory; Relativity
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Multimodal learning via exploring deep semantic similarity
Hu, Di1; Lu, Xiaoqiang2; Li, Xuelong2 Source: MM 2016 - Proceedings of the 2016 ACM Multimedia Conference, p 342-346, October 1, 2016, MM 2016 - Proceedings of the 2016 ACM Multimedia Conference; ISBN-13: 9781450336031; DOI: 10.1145/2964284.2967239; Conference: 24th ACM Multimedia Conference, MM 2016, October 15, 2016 - October 19, 2016; Sponsor: ACM SIGMM;
Publisher: Association for Computing Machinery, IncAuthor affiliation: 1 OPTIMAL, Northwestern Polytechnical University, 127 West Youyi Road, Xi'an Shaanxi, China2 OPTIMAL, Chinese Academy of Sciences, Xi'an Institute of Optics and Precision Mechanics, Xi'an Shaanxi, China
Abstract: Deep learning is skilled at learning representation from raw data, which are embedded in the semantic space. Traditional multimodal networks take advantage of this, and maximize the joint distribution over the representations of different modalities. However, the similarity among the representations are not emphasized, which is an important property for multimodal data. In this paper, we will introduce a novel learning method for multimodal networks, named as Semantic Similarity Learning (SSL), which aims at training the model via enhancing the similarity between the highlevel features of different modalities. Sets of experiments are conducted for evaluating the method on different multimodal networks and multiple tasks. The experimental results demonstrate the effectiveness of SSL in keeping the shared information and improving the discrimination. Particularly, SSL shows its ability in encouraging each modality to learn transferred knowledge from the other one when faced with missing data. © 2016 ACM. (19 refs.)Main Heading: Personnel trainingControlled terms: SemanticsUncontrolled terms: Deep learning - High-level features - Joint distributions - Learning methods - Multi-modal learning - Multimodal network - Semantic similarity - Shared informationClassification Code: 912.4 PersonnelPersonnel
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Yb-doped large-mode-Area aluminosilicate laser fibre fabricated by chelate precursor doping technique
Peng, Kun1, 2, 3; Wang, Zhen1, 2, 3; Zhan, Huan2; Ni, Li2; Gao, Cong2; Wang, Xiaolong2; Wang, Yuying2; Wang, Jianjun2; Jing, Feng2; Lin, Aoxiang2 Source: Electronics Letters, v 52, n 23, p 1942-1944, November 10, 2016
; ISSN: 00135194; DOI: 10.1049/el.2016.3350;
Publisher: Institution of Engineering and TechnologyAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics (XIOPM), Chinese Academy of Sciences (CAS), Xi'an; 710119, China2 Laser Fusion Research Center, College of Materials Science and Opto-Electronic Technology, China Academy of Engineering Physics (CAEP), Mianyang; 621900, China3 Graduate School of Chinese Academy of Sciences (CAS), Beijing; 100049, China
Abstract: A modified chelate precursor doping technique using high-purity materials and accurate gas flow control system is proposed to fabricate an efficient ytterbium-doped large-mode-Area silica fibre for laser development. This technique enables to make homogeneous large-core preform with symmetrical shape, relatively low numerical aperture of ∼0.06 and large-core size of over 4 mm. Homemade preform was drawn into standard fibre for testing and fully characterised by electron probe microanalysis and time-of-flight secondary ion mass spectrometry. On the basis of two-stage master oscillator power amplifier system, 1 kW laser output with slope efficiency of 81.0% was realised at ∼1064 nm. © The Institution of Engineering and Technology 2016. (13 refs.)Main Heading: Secondary ion mass spectrometryControlled terms: Chelation - Electron probe microanalysis - Flight control systems - Flow of gases - Mass spectrometry - Optical waveguides - Power amplifiers - Preforming - YtterbiumUncontrolled terms: Chelate precursor - Doping techniques - High purity materials - Large-core size - Master oscillator power amplifier systems - Numerical aperture - Slope efficiencies - Time of flight secondary ion mass spectrometryClassification Code: 547.2 Rare Earth MetalsRare Earth Metals - 631.1.2 Gas DynamicsGas Dynamics - 652.3 Aircraft Instruments and EquipmentAircraft Instruments and Equipment - 713.1 AmplifiersAmplifiers - 714.3 WaveguidesWaveguides - 801 ChemistryChemistry - 802.2 Chemical ReactionsChemical Reactions
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Similarity Constraints-Based Structured Output Regression Machine: An Approach to Image Super-Resolution
Deng, Cheng1; Xu, Jie1; Zhang, Kaibing2; Tao, Dacheng3; Gao, Xinbo1; Li, Xuelong4 Source: IEEE Transactions on Neural Networks and Learning Systems, v 27, n 12, p 2472-2485, December 2016
; ISSN: 2162237X, E-ISSN: 21622388; DOI: 10.1109/TNNLS.2015.2468069;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 School of Electronic Engineering, Xidian University, Xi'an; 710071, China2 School of Computer and Information Science, Hubei Engineering University, Xiaogan; 432000, China3 Centre for Quantum Computation and Intelligent Systems, Faculty of Engineering and Information Technology, University of Technology, Sydney, 81 Broadway Street, Ultimo; NSW; 2007, Australia4 Center for Optical Imagery Analysis and Learning (OPTIMAL), State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, Shaanxi; 710119, China
Abstract: For regression-based single-image super-resolution (SR) problem, the key is to establish a mapping relation between high-resolution (HR) and low-resolution (LR) image patches for obtaining a visually pleasing quality image. Most existing approaches typically solve it by dividing the model into several single-output regression problems, which obviously ignores the circumstance that a pixel within an HR patch affects other spatially adjacent pixels during the training process, and thus tends to generate serious ringing artifacts in resultant HR image as well as increase computational burden. To alleviate these problems, we propose to use structured output regression machine (SORM) to simultaneously model the inherent spatial relations between the HR and LR patches, which is propitious to preserve sharp edges. In addition, to further improve the quality of reconstructed HR images, a nonlocal (NL) self-similarity prior in natural images is introduced to formulate as a regularization term to further enhance the SORM-based SR results. To offer a computation-effective SORM method, we use a relative small nonsupport vector samples to establish the accurate regression model and an accelerating algorithm for NL self-similarity calculation. Extensive SR experiments on various images indicate that the proposed method can achieve more promising performance than the other state-of-the-art SR methods in terms of both visual quality and computational cost. © 2015 IEEE. (50 refs.)Main Heading: Image processingControlled terms: Optical resolving power - Pixels - Regression analysisUncontrolled terms: Accelerating algorithm - Computational burden - Image super resolutions - Low resolution images - Self-similarities - structured output - Super resolution - Support vector regression (SVR)Classification Code: 741.1 Light/OpticsLight/Optics - 922.2 Mathematical StatisticsMathematical Statistics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Unsupervised 3D Local Feature Learning by Circle Convolutional Restricted Boltzmann Machine
Han, Zhizhong1; Liu, Zhenbao1; Han, Junwe1; Vong, Chi-Man2; Bu, Shuhui1; Li, Xuelong3 Source: IEEE Transactions on Image Processing, v 25, n 11, p 5331-5344, November 2016
; ISSN: 10577149; DOI: 10.1109/TIP.2016.2605920;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 Northwestern Polytechnical University, Xi'an; 710072, China2 Department of Computer and Information Science, University of Macau, 999078, China3 State Key Laboratory of Transient Optics and Photonics, Center for OPTical IMagery Analysis and Learning, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China
Abstract: Extracting local features from 3D shapes is an important and challenging task that usually requires carefully designed 3D shape descriptors. However, these descriptors are hand-crafted and require intensive human intervention with prior knowledge. To tackle this issue, we propose a novel deep learning model, namely circle convolutional restricted Boltzmann machine (CCRBM), for unsupervised 3D local feature learning. CCRBM is specially designed to learn from raw 3D representations. It effectively overcomes obstacles such as irregular vertex topology, orientation ambiguity on the 3D surface, and rigid or slightly non-rigid transformation invariance in the hierarchical learning of 3D data that cannot be resolved by the existing deep learning models. Specifically, by introducing the novel circle convolution, CCRBM holds a novel ring-like multi-layer structure to learn 3D local features in a structure preserving manner. Circle convolution convolves across 3D local regions via rotating a novel circular sector convolution window in a consistent circular direction. In the process of circle convolution, extra points are sampled in each 3D local region and projected onto the tangent plane of the center of the region. In this way, the projection distances in each sector window are employed to constitute a novel local raw 3D representation called projection distance distribution (PDD). In addition, to eliminate the initial location ambiguity of a sector window, the Fourier transform modulus is used to transform the PDD into the Fourier domain, which is then conveyed to CCRBM. Experiments using the learned local features are conducted on three aspects: global shape retrieval, partial shape retrieval, and shape correspondence. The experimental results show that the learned local features outperform other state-of-the-art 3D shape descriptors. © 2016 IEEE. (71 refs.)Main Heading: ConvolutionControlled terms: Deep learning - Fourier transforms - Invariance - MetadataUncontrolled terms: 3-D shape - Geometry processing - Hierarchical learning - Multilayer structures - Non-rigid transformation - Projection distance - Restricted boltzmann machine - Shape correspondencesClassification Code: 716.1 Information Theory and Signal ProcessingInformation Theory and Signal Processing - 921.3 Mathematical TransformationsMathematical Transformations
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Effect of fabrication errors of double-layer BOE on diffractive efficiency
Ma, Zebin1; Kang, Fuzeng1; Wang, Hao1 Source: Hongwai yu Jiguang Gongcheng/Infrared and Laser Engineering, v 45, n 9, September 25, 2016; Language: Chinese
; ISSN: 10072276; DOI: 10.3788/IRLA201645.0918001; Article number: 0918001;
Publisher: Chinese Society of AstronauticsAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics of Chinese Academy of Sciences, Xi'an; 710119, China
Abstract: With the development of optical technology, optic-mechanical-electric technology becomes a trend. An integrated, arrayed and miniaturized optical system was required. Binary optical element is famous for its excellent performance in light-wave transformation. Double-layer binary optical element has high diffraction efficiency over wide wavelength range. However, in the fabrication of double layer BOE, many errors occurred, such as height error, periodic error, multi-mask fabrication error etc.A theoretical analysis of these errors was carried out based on scalar diffraction theory, and a MATLAB simulation was implemented. The simulation result indicated that the diffraction efficiency deteriorated if the height errors occurred in different direction rather than in the same direction. Therefore, height errors from different direction should be avoid in fabrication. If the multi-mask fabrication error is occurred from different direction, the diffraction efficiency will decrease more quickly than from the same direction, so multi-mask fabrication error from different direction should be avoid as much as possible. Compared to height error and multi-mask fabrication error, other four errors have varying degrees of impact on the diffraction efficiency. © 2016, Editorial Board of Journal of Infrared and Laser Engineering. All right reserved. (17 refs.)Main Heading: ErrorsControlled terms: Bins - Diffraction - Diffraction efficiency - Efficiency - Fabrication - Masks - MATLAB - Optical systemsUncontrolled terms: Binary optical element - Diffractive efficiency - Double layers - Fabrication errors - Matlab simulations - Optical technology - Scalar diffraction theory - Wavelength rangesClassification Code: 694.4 StorageStorage - 714.2 Semiconductor Devices and Integrated CircuitsSemiconductor Devices and Integrated Circuits - 741.3 Optical Devices and SystemsOptical Devices and Systems - 913.1 Production EngineeringProduction Engineering - 921 MathematicsMathematics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


The new high-speed switching study of ultra-short laser pulse technology
Sun, Bo1, 2, 3; Gou, Yongsheng1, 2, 3; Wang, Dahui4; Liu, Baiyu1, 2; Zhao, Xueqing4; Bai, Yonglin1, 2 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 9686, 2016, 8th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optoelectronic Materials and Devices
; ISSN: 0277786X, E-ISSN: 1996756X; ISBN-13: 9781628419214; DOI: 10.1117/12.2242364; Article number: 96860Z; Conference: 8th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optoelectronic Materials and Devices, AOMATT 2016, April 26, 2016 - April 29, 2016; Sponsor: Chinese Academy of Sciences, Institute of Optics and Electronics (IOE); The Chinese Optical Society (COS);
Publisher: SPIEAuthor affiliation: 1 Key Laboratory of Ultra-fast Diagnostics Technology of CAS, Xi'An Institute of Optics and Precision Mechanics, Xi'an, China2 State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics, Xi'an, China3 University of Chinese Academy of Sciences, Beijing, China4 State Key Laboratory of Laser Interaction with Matter, Northwest Institute of Nuclear Technology, Xi'an, China
Abstract: Ultrafast phenomenon has presented widely in natural phenomenon and scientific and technological research. Therefore, study on ultrafast phenomenon is of great important in many research and technology fields. In recent years, the development and application of ultra-short laser pulse has been covered many areas. It has been developed into a powerful tool used to research ultrafast phenomena. In the implementation process of the ultra-short laser pulses, high-speed switching plays a vital role. The difficulty of high-speed switching design is to make the ultrafast electric pulse load on the both ends of the crystal with minimum distortion and delay. It is very difficult to switch electro-optic crystal at a high frequency in traditional method. In this paper, a new method is designed, which combined the electro-optic crystal and micro-strip line. The crystal is a part of the transmission path and the signal path of the micro-strip line is broadened or narrowed continuously to make the impedance matching to 50 ohm. The good match between pulse signal and the crystal make sure the high frequency switches of the crystal. The amplitude loss is less than 11%, and the delay is less than 1 nanosecond. © 2016 SPIE. (5 refs.)Main Heading: Electric linesControlled terms: Impedance matching (electric) - Laser pulses - Manufacture - Materials testing - Microstrip lines - Optoelectronic devices - Strip telecommunication lines - Switching - Ultrafast lasers - Ultrafast phenomena - Ultrashort pulsesUncontrolled terms: Electric control - Electric pulse - High-speed switching - Micro-strips - Short laser pulseClassification Code: 537.1 Heat Treatment ProcessesHeat Treatment Processes - 706.2 Electric Power Lines and EquipmentElectric Power Lines and Equipment - 741.3 Optical Devices and SystemsOptical Devices and Systems - 744.1 Lasers, GeneralLasers, General - 951 Materials ScienceMaterials Science
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Detection and tracking of multi-space junks in star images
Deng, Wenkang1, 2; Song, Zongxi1 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 10033, 2016, Eighth International Conference on Digital Image Processing, ICDIP 2016
; ISSN: 0277786X, E-ISSN: 1996756X; ISBN-13: 9781510605039; DOI: 10.1117/12.2244285; Article number: 100330N; Conference: 8th International Conference on Digital Image Processing, ICDIP 2016, May 20, 2016 - May 23, 2016; Sponsor: Chengdu University of Information Technology; Chinese Academy of Sciences Chengdu Institute of Computer Applications; International Association of Computer Science and Information Technology; Sichuan Province Computer Federation;
Publisher: SPIEAuthor affiliation: 1 Space Optics Laboratory, Xi'An Institute of Optics and Precision Mechanics of CAS, Xi'an; 710119, China2 University of Chinese Academy of Sciences, Beijing; 100049, China
Abstract: An algorithm of detection and tracking of multiple small moving space junks under the complex star sequential images is proposed in this paper. Firstly we take image smoothing and adaptive threshold segment to improve the weight of junks. Furthermore, back neighborhood frame correlation (BNFC) is proposed to detect and locate the junk which is sheltered by bigger interfaced stars. Through cross projection method, we could extract the centroid of the moving junks. At last, the Kalman Filter is used to track and estimate the trajectory of moving junks. Experiments show that through this algorithm the multiple small space junks could be detected and tracked effectively and accurately under complex star background with good performance in low error rate and good real-time processing. © 2016 SPIE. (7 refs.)Main Heading: Space debrisControlled terms: Image processing - Image segmentation - Kalman filters - Stars - Tracking (position)Uncontrolled terms: Adaptive thresholds - Cross projection - Detection and tracking - Frame correlations - Projection method - Realtime processing - Sequential images - Small moving space junksClassification Code: 656.1 Space FlightSpace Flight - 657.2 Extraterrestrial Physics and Stellar PhenomenaExtraterrestrial Physics and Stellar Phenomena
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Optimal design of a space target acquisition optical system with small F-number
Yan, Peipei1, 2; She, Wenji1; Liu, Kai1; Duan, Jing1; Jiang, Kai1; Shan, Qiusha1 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 10154, 2016, Advanced Optical Design and Manufacturing Technology and Astronomical Telescopes and Instrumentation
; ISSN: 0277786X, E-ISSN: 1996756X; DOI: 10.1117/12.2243586; Article number: 1015402; Conference: International Symposium on Advanced Optical Design and Manufacturing Technologies and International Symposium on Astronomical Telescope and Instrumentation, May 9, 2016 - May 11, 2016; Sponsor: China High-Tech Industrialization Association (CHIA); Chinese Society for Optical Engineering (CSOE);
Publisher: SPIEAuthor affiliation: 1 Photoelectric Measurement and Control Technology Research Department, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy Sciences, Xi'an; 710119, China2 University of Chinese Academy of Sciences, Beijing; 100039, China
Abstract: A kind of space target acquisition optical system with small F-number was designed. The system had a working wavelength range of 0.45∼0.85μm, an effective focal length of 240 mm, a field of view is 2ω=3°, and an F-Number of F/2. The system characteristic is that the structure is simple. And the especial requirements of the spot, energy concentration, distortion and lateral color etc. are all satisfied. The primary and secondary mirrors are all spheres, so the difficulty and cost of machining are reduced. Moreover, the temperature characteristic of the system is analyzed. The temperature request is satisfied. © 2016 SPIE. (6 refs.)Main Heading: Optical systemsControlled terms: Manufacture - Mergers and acquisitions - Optical design - Radio telescopes - Telescopes - Tracking (position)Uncontrolled terms: Acquisition systems - Effective focal lengths - Energy concentration - Space detection - System characteristics - Temperature analysis - Temperature characteristic - Wavelength rangesClassification Code: 537.1 Heat Treatment ProcessesHeat Treatment Processes - 657.2 Extraterrestrial Physics and Stellar PhenomenaExtraterrestrial Physics and Stellar Phenomena - 741.1 Light/OpticsLight/Optics - 741.3 Optical Devices and SystemsOptical Devices and Systems
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


61 nm generation from a tilted fiber grating based all-fiber mode locked Erbium doped laser
Wang, Tianxing1; Yan, Zhijun2; Mou, Chengbo1; Zhou, Kaiming3; Zhang, Lin3; Wang, Tingyun1 Source: Optics InfoBase Conference Papers, August 29, 2016, Bragg Gratings, Photosensitivity, and Poling in Glass Waveguides, BGPP 2016; ISBN-13: 9781943580170; DOI: 10.1364/BGPP.2016.BM3B.6; Conference: Bragg Gratings, Photosensitivity, and Poling in Glass Waveguides, BGPP 2016, September 5, 2016 - September 8, 2016; Sponsor: American Elements; Australian Optical Society; cudos; Modular Photonics; OSA;
Publisher: OSA - The Optical SocietyAuthor affiliation: 1 Key Laboratory of Specialty Fiber Optics and Optical Access Networks, Shanghai University, Shanghai; 200072, China2 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Science, Xi'an, 710119, China3 Aston Institute of Photonic Technologies (AIPT), Aston University, Birmingham; B4 7ET, United Kingdom
Abstract: By incorporating a tilted fiber grating in a dispersion managed fiber laser cavity, we have achieved ultrashort pulse generation with a flat spectral width of 61 nm from an all-fiber mode locked Erbium doped laser. © OSA 2016. (8 refs.)Main Heading: Mode-locked fiber lasersControlled terms: Bragg gratings - Erbium - Fiber lasers - Fibers - Glass - Light sensitive materials - Locks (fasteners) - Photosensitivity - Ultrashort pulses - WaveguidesUncontrolled terms: All fiber - Dispersion managed fibers - Erbium doped laser - Spectral widths - Tilted fiber gratings - Ultrashort pulse generationClassification Code: 547.2 Rare Earth MetalsRare Earth Metals - 714.3 WaveguidesWaveguides - 741.1 Light/OpticsLight/Optics - 741.3 Optical Devices and SystemsOptical Devices and Systems - 744.1 Lasers, GeneralLasers, General - 744.4 Solid State LasersSolid State Lasers - 812.3 GlassGlass
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Speckle-correlation microscopic imaging through scattering medium
Zhou, Meiling1, 2; Singh, Alok Kumar1; Pedrini, Giancarlo1; Osten, Wolfgang1; Yao, Baoli2 Source: Optics InfoBase Conference Papers, July 18, 2016, Digital Holography and Three-Dimensional Imaging, DH 2016; ISBN-13: 9781943580156; DOI: 10.1364/DH.2016.DT1E.2; Conference: Digital Holography and Three-Dimensional Imaging, DH 2016, July 25, 2016 - July 28, 2016; Sponsor: ALPAO; American Elements; Intel; raytrix; Space UNSW Canberra;
Publisher: OSA - The Optical SocietyAuthor affiliation: 1 Institut für Technische Optik ITO, University of Stuttgart, Pfaffenwaldring 9, Stuttgart; 70569, Germany2 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China
Abstract: In this paper we are presenting a non-invasive and lensless method to utilize a scattering media for microscopic imaging. Thanks to its lens-like property, we can adjust the magnification and resolution of the system and reconstruct the microscopic object using phase retrieval technique from the autocorrelation of a single-shot speckle intensity distribution. © OSA 2016. (10 refs.)Main Heading: Microscopic examinationControlled terms: Holography - Imaging systems - SpeckleUncontrolled terms: Microscopic imaging - Microscopic objects - Phase retrieval - Scattering media - Scattering medium - Single shots - Speckle correlations - Speckle intensityClassification Code: 741.1 Light/OpticsLight/Optics - 746 Imaging TechniquesImaging Techniques
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Multi-photon entangled quantum state from integrated optical frequency combs
Reimer, Christian1; Kues, Michael1; Roztocki, Piotr1; Caspani, Lucia1, 2; Bromberg, Yaron3; Wetzel, Benjamin1; Little, Brent E.4; Chu, Sai T.5; Moss, David J.1, 6; Morandotti, Roberto1 Source: Optics InfoBase Conference Papers, August 15, 2016, Latin America Optics and Photonics Conference, LAOP 2016; ISBN-13: 9781943580163; DOI: 10.1364/LAOP.2016.LTh2B.2; Conference: Latin America Optics and Photonics Conference, LAOP 2016, August 22, 2016 - August 26, 2016; Sponsor: Centro de Investigaciones en Optica, A.C.; CONACYT; INAOE; SEP; Universidad de Guanajuata;
Publisher: OSA - The Optical SocietyAuthor affiliation: 1 INRS-EMT, 1650 Boulevard Lionel-Boulet, Varennes; QC; J3X 1S2, Canada2 School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh; EH14 4AS, United Kingdom3 Department of Applied Physics, Yale University, New Haven; CT; 06520, United States4 Xi'an Institute of Optics and Precision Mechanics of CAS, Xi'an, China5 Department of Physics and Material Science, City University of Hong Kong, Tat Chee Avenue, Hong Kong6 Centre for Micro Photonics, Swinburne University of Technology, Hawthorne; VIC; 3122, Australia
Abstract: We show the generation of four-photon entangled quantum states exploiting spontaneous four-wave mixing and the multi-mode characteristic of integrated micro-resonators. This is confirmed by four-photon quantum interference and quantum state tomography. © OSA 2016. (13 refs.)Main Heading: Quantum theoryControlled terms: Four wave mixing - Photonics - Photons - Quantum entanglement - Quantum optics - ResonatorsUncontrolled terms: Micro resonators - Multimodes - Multiphotons - Optical frequency combs - Quantum interference - Quantum state - Quantum state tomography - Spontaneous four-wave mixingClassification Code: 741.1 Light/OpticsLight/Optics - 931.3 Atomic and Molecular PhysicsAtomic and Molecular Physics - 931.4 Quantum Theory; Quantum MechanicsQuantum Theory; Quantum Mechanics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


MoS2-mode-locked fiber laser delivering ultrashort pulses with three types of sidebands
Lu, Feifei1; Liu, Xueming1; Yang, Huiran1 Source: Optics InfoBase Conference Papers, August 29, 2016, Australian Conference on Optical Fibre Technology, ACOFT 2016; ISBN-13: 9781943580170; DOI: 10.1364/ACOFT.2016.JM6A.1; Conference: Australian Conference on Optical Fibre Technology, ACOFT 2016, September 5, 2016 - September 8, 2016; Sponsor: American Elements; Australian Optical Society; cudos; Modular Photonics; OSA;
Publisher: OSA - The Optical SocietyAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China
Abstract: We demonstrate an erbium-doped fiber laser passively mode-locked by a monolayer MoS2which is covered onto a fiber taper. Three types of sidebands, e.g. peak, peak-dip and dip spectral sidebands, are observed in the experiment. © OSA 2016. (6 refs.)Main Heading: Mode-locked fiber lasersControlled terms: Fiber lasers - Fibers - Molybdenum compounds - Optical fibers - Passive mode locking - Ultrashort pulsesUncontrolled terms: Erbium doped fiber laser - Fiber taper - Passively mode-locked - Spectral sidebandsClassification Code: 741.1.2 Fiber OpticsFiber Optics - 744.1 Lasers, GeneralLasers, General - 744.4 Solid State LasersSolid State Lasers
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Status of the large area MCP-PMT in China
Gao, Feng1; Qian, Sen1; Liu, Shulin1; Ning, Zhe1; Wang, Yifang1; Zhao, Tianchi1; Heng, Yuekun1; Liu, Hulin2; Li, Weihua2; Tian, Jinshou2; Wei, Yonglin2; Xin, Liwei2; Huang, Guorui3; Li, Dong3; Ren, Ling3; Sun, Jianning2; Si, Shuguang3; Qi, Ming4 Source: Proceedings of Science, v Part F128556, 2016, 38th International Conference on High Energy Physics, ICHEP 2016; E-ISSN: 18248039; Conference: 38th International Conference on High Energy Physics, ICHEP 2016, August 3, 2016 - August 10, 2016;
Publisher: Proceedings of Science (PoS)Author affiliation: 1 Institute of High Energy Physics, Chinese Academy of Sciences, Beijing; 100049, China2 Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710068, China3 Nanjing, North Night Vision Tech. Ltd., Nanjing; 211106, China4 Department of Physics, Nanjing University, Nanjing; 210093, China
Abstract: For the next generation neutrino experiment, number of experienced researchers and engineers in research institutes and companies related to PMT fabrication in China jointly worked on the large area MCP-PMT collaboration group. In the past 5 years by collaborative work, the 8-inch and 20-inch prototypes were produced. And also get the high detection efficiency 20-inch MCP-PMT for JUNO in 2015, and get the 75% order of the JUNO-PMT. This manuscript will introduce the progress of the R&D of this new design of the MCP-PMT, also the performance tested result in the PMT Lab in IHEP. © Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND 4.0). (4 refs.)Main Heading: High energy physicsUncontrolled terms: Collaboration group - Collaborative Work - Detection efficiency - MCP-PMT - Neutrino experiments - Research institutesClassification Code: 932.1 High Energy PhysicsHigh Energy Physics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Research progress of magneto-optical property of chalcogenide glasses
Chen, Gang1, 2; Xu, Yantao1, 3; Guo, Haitao1; Lu, Min1; Yu, Fengxia2; Xiao, Xusheng1, 3; Peng, Bo1 Source: Cailiao Daobao/Materials Review, v 30, n 10, p 84-88, October 10, 2016; Language: Chinese
; ISSN: 1005023X; DOI: 10.11896/j.issn.1005-023X.2016.19.012;
Publisher: Cailiao Daobaoshe/ Materials ReviewAuthor affiliation: 1 Xi'an Institute of Optics and Procession Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China2 School of Materials Science and Engineering, Changchun University of Science and Technology, Changchun; 130022, China3 University of Chinese Academy of Sciences, Beijing; 100049, China
Abstract: Recently, the magneto-optical chalcogenide glasses have attracted great interest in the field of magneto-optical materials owing to their excellent properties, including but not limited to the independence of Verdet constant to temperature, easy fabrication of optical fiber and optical waveguide, etc. The progress in investigation and development of magneto-optical properties in chalcogenide glasses is systematically introduced. Meanwhile, the factors that influence the Verdet constant of chalcogenide glasses are analyzed in detail. In addition, the possible development direction for chalcogenide glass is discussed. © 2016, Materials Review Magazine. All right reserved. (44 refs.)Main Heading: Optical propertiesControlled terms: Chalcogenides - Faraday effect - Glass - Optical fiber fabrication - Optical fibers - Optical glassUncontrolled terms: Chalcogenide glass - Development directions - Easy fabrication - Magnetic optical glass - Magneto-optical - Magneto-optical materials - Magnetooptical properties - Verdet constantClassification Code: 701.1 Electricity: Basic Concepts and PhenomenaElectricity: Basic Concepts and Phenomena - 741.1 Light/OpticsLight/Optics - 741.1.2 Fiber OpticsFiber Optics - 804.2 Inorganic CompoundsInorganic Compounds - 812.3 GlassGlass
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Compact Structure Hashing via Sparse and Similarity Preserving Embedding
Ye, Renzhen1, 2; Li, Xuelong1 Source: IEEE Transactions on Cybernetics, v 46, n 3, p 718-729, March 2016
; ISSN: 21682267; DOI: 10.1109/TCYB.2015.2414299; Article number: 7089246;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 Center for Optical Imagery Analysis and Learning, State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, China2 School of Electronics and Information Engineering, Xi'an Jiaotong University, Xi'an, China
Abstract: Over the past few years, fast approximate nearest neighbor (ANN) search is desirable or essential, e.g., in huge databases, and therefore many hashing-based ANN techniques have been presented to return the nearest neighbors of a given query from huge databases. Hashing-based ANN techniques have become popular due to its low memory cost and good computational complexity. Recently, most of hashing methods have realized the importance of the relationship of the data and exploited the different structure of data to improve retrieval performance. However, a limitation of the aforementioned methods is that the sparse reconstructive relationship of the data is neglected. In this case, few methods can find the discriminating power and own the local properties of the data for learning compact and effective hash codes. To take this crucial issue into account, this paper proposes a method named special structure-based hashing (SSBH). SSBH can preserve the underlying geometric information among the data, and exploit the prior information that there exists sparse reconstructive relationship of the data, for learning compact and effective hash codes. Upon extensive experimental results, SSBH is demonstrated to be more robust and more effective than state-of-the-art hashing methods. © 2015 IEEE. (48 refs.)Main Heading: Hash functionsControlled terms: Nearest neighbor searchUncontrolled terms: Approximate nearest neighbors (ANN) - Compact structures - Different structure - Discriminating power - Geometric information - Retrieval performance - Similarity preserving - Sparse reconstructive
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


High-sensitivity plasmonic sensor based on perfect absorber with metallic nanoring structures
Lu, Xiaoyuan1; Wan, Rengang1; Liu, Feng1; Zhang, Tongyi1 Source: Journal of Modern Optics, v 63, n 2, p 177-183, January 19, 2016
; ISSN: 09500340, E-ISSN: 13623044; DOI: 10.1080/09500340.2015.1066459;
Publisher: Taylor and Francis Ltd.Author affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xian Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xian, China
Abstract: We propose a nanoring array structure backed by a metal mirror to achieve perfect infrared absorber with absorption as high as 99.99%. The frequency of the absorption peak strongly depends on the refractive index surrounding the structured surface, while the maximum of absorption remains constant with varying the surrounding refractive index. These features can be used as plasmonic sensor for refractive index measurement. This plasmonic sensor possesses the figure of merit 700. In addition, we investigate the effect of various materials on the performance of the sensor, including, TiN, and dielectric spacer and Au, Ag, Al, and Cu back plate and top structure. Due to the high sensitivity and simple sensing scheme, the sensing strategy can find potential applications in chemical and biosensor applications. © 2015 Taylor & Francis. (46 refs.)Main Heading: Refractive indexControlled terms: Infrared detectors - Nanorings - Nanostructured materials - PlasmonsUncontrolled terms: Biosensor applications - Dielectric spacers - Infra-red sensor - Nano-ring structures - Perfect absorber - Refractive index measurement - Structured surfaces - Surrounding refractive indices (SRI)
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Weakly supervised human fixations prediction
Zhang, Luming1; Li, Xuelong2; Nie, Liqiang3; Yang, Yi4; Xia, Yingjie5 Source: IEEE Transactions on Cybernetics, v 46, n 1, p 258-269, January 2016
; ISSN: 21682267; DOI: 10.1109/TCYB.2015.2400821; Article number: 7152897;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 School of Computer Science and Information Engineering, Hefei University of Technology, Hefei, China2 Center for Optical Imagery Analysis and Learning, State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, China3 School of Computing, National University of Singapore, Singapore, Singapore4 Centre for Quantum Computation and Intelligent Systems, University of Technology, Sydney; NSW, Australia5 College of Computer Science, Zhejiang University, Hangzhou, China
Abstract: Automatically predicting human eye fixations is a useful technique that can facilitate many multimedia applications, e.g., image retrieval, action recognition, and photo retargeting. Conventional approaches are frustrated by two drawbacks. First, psychophysical experiments show that an object-level interpretation of scenes influences eye movements significantly. Most of the existing saliency models rely on object detectors, and therefore, only a few prespecified categories can be discovered. Second, the relative displacement of objects influences their saliency remarkably, but current models cannot describe them explicitly. To solve these problems, this paper proposes weakly supervised fixations prediction, which leverages image labels to improve accuracy of human fixations prediction. The proposed model hierarchically discovers objects as well as their spatial configurations. Starting from the raw image pixels, we sample superpixels in an image, thereby seamless object descriptors termed object-level graphlets (oGLs) are generated by random walking on the superpixel mosaic. Then, a manifold embedding algorithm is proposed to encode image labels into oGLs, and the response map of each prespecified object is computed accordingly. On the basis of the object-level response map, we propose spatial-level graphlets (sGLs) to model the relative positions among objects. Afterward, eye tracking data is employed to integrate these sGLs for predicting human eye fixations. Thorough experiment results demonstrate the advantage of the proposed method over the state-of-the-art. © 2015 IEEE. (91 refs.)Main Heading: Eye movementsControlled terms: Forecasting - Image retrieval - Pixels - Random processesUncontrolled terms: Action recognition - Conventional approach - Embedding algorithms - Multimedia applications - Psychophysical experiments - Relative displacement - Relative positions - Spatial configuration
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


In Situ Surface Assembly Derived Ultralow Refractive Index MgF2-SiO2Hybrid Film for Tri-Layer Broadband Antireflective Coating
Cui, Xinmin1; Ding, Ruimin1; Wang, Mengchao1; Zhang, Cong1; Zhang, Ce1; Zhang, Jing1; Xu, Yao2 Source: Advanced Optical Materials, v 4, n 5, p 722-730, May 1, 2016; E-ISSN: 21951071; DOI: 10.1002/adom.201500595;
Publisher: Wiley-VCH VerlagAuthor affiliation: 1 Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan, Shanxi; 030001, China2 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, Shaanxi; 710119, China
Abstract: For the broadband antireflective (AR) coating working in specific wavelengths, the precise control over refractive index and film thickness of each layer is critical to guarantee the peak position locating at the targeted wavelengths. In this paper, a simple sol-gel procedure without post-treatment is used to prepare MgF2-SiO2hybrid coating with tunable refractive index for the fabrication of tri-layer tri-wavelength broadband AR coating. The MgF2-SiO2coating with ultralow refractive index of 1.12 is realized through in situ surface assembly of negatively charged silanol groups on vesicle-like MgF2particles to obtain porous crosslinking structure. The electrostatic attraction between the negatively charged silanol groups and positively charged MgF2colloidal particles plays a key role. Furthermore, the MgF2-SiO2coating with a wide range of refractive index between 1.20 and 1.44 is achieved by adjusting the addition amount of acid-catalyzed silica sol into the vesicle-like MgF2sol. According to the theoretical design, a tri-layer broadband AR coating with refractive index model of 1.12/1.26/1.36 is prepared, which can enhance the transmittance of quartz substrate to near 100% simultaneously at 351, 527, and 1053 nm. The MgF2-SiO2coatings with ultralow refractive index of 1.12 and tunable refractive index of 1.20-1.44 are prepared by a facile sol-gel procedure without post-treatment. Then, a tri-layer broadband AR coating with refractive index model of 1.12/1.26/1.36 is realized with excellent transmittance of nearly 100% simultaneously at 351, 527, and 1053 nm. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. (39 refs.)Main Heading: Refractive indexControlled terms: Antireflection coatings - Coatings - Sol-gel process - Sol-gelsUncontrolled terms: Anti reflective coatings - Broadband AR coatings - Cross-linking structures - Electrostatic attractions - MgF2-SiO2 - Tunable refractive indexes - Ultralow refractive indexes - Ultralow refractive indices
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Perspective of monochromatic gamma-ray line detection with the High Energy cosmic-Radiation Detection (HERD) facility onboard China's space station
Huang, Xiaoyuan1; Lamperstorfer, Anna S.1; Tsai, Yue-Lin Sming2; Xu, Ming3; Yuan, Qiang4; Chang, Jin5; Dong, Yong-Wei3; Hu, Bing-Liang6; Lü, Jun-Guang7; Wang, Le6; Wu, Bo-Bing3; Zhang, Shuang-Nan3 Source: Astroparticle Physics, v 78, p 35-42, May 2016
; ISSN: 09276505; DOI: 10.1016/j.astropartphys.2016.02.003;
Publisher: ElsevierAuthor affiliation: 1 Physik-Department T30d, Technische Universität München, James-Franck-Straße, Garching, Germany2 Kavli IPMU (WPI), University of Tokyo, Kashiwa, Chiba, Japan3 Key Laboratory of Particle Astrophysics, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, China4 Department of Astronomy, University of Massachusetts, Amherst; MA, United States5 Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing, China6 Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, China7 Center of Experimental Physics, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, China
Abstract: HERD is the High Energy cosmic-Radiation Detection instrument proposed to operate onboard China's space station in the 2020s. It is designed to detect energetic cosmic ray nuclei, leptons and photons with a high energy resolution (∼1% for electrons and photons and 20% for nuclei) and a large geometry factor (>3 m2sr for electrons and diffuse photons and > [2]m2sr for nuclei). In this work we discuss the capability of HERD to detect monochromatic γ-ray lines, based on simulations of the detector performance. It is shown that HERD will be one of the most sensitive instruments for monochromatic γ-ray searches at energies between ∼ 10 to a few hundred GeV. Above hundreds of GeV, Cherenkov telescopes will be more sensitive due to their large effective area. As a specific example, we show that a good portion of the parameter space of a supersymmetric dark matter model can be probed with HERD. © 2016 Elsevier B.V. All rights reserved. (61 refs.)Main Heading: Gamma raysControlled terms: Cosmic rays - Cosmology - Galaxies - Photons - Space stationsUncontrolled terms: Dark matter - Detector performance - Gamma-ray line - High-energy resolution - Large effective areas - MSSM - Sensitive instruments - Supersymmetric dark matterClassification Code: 656.1 Space FlightSpace Flight - 657 Space PhysicsSpace Physics - 657.2 Extraterrestrial Physics and Stellar PhenomenaExtraterrestrial Physics and Stellar Phenomena - 931.3 Atomic and Molecular PhysicsAtomic and Molecular Physics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Spatiotemporal soliton solution to generalized nonlinear Schrödinger equation with a parabolic potential in Kerr media
Kong, Youchao1 Source: Optics Communications, v 371, p 27-33, July 15, 2016
; ISSN: 00304018; DOI: 10.1016/j.optcom.2016.03.004;
Publisher: ElsevierAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, China
Abstract: A class of new spatiotemporal solitary solution to nonlinear Schrödinger equation with a parabolic potential is investigated analytically and numerically using the F-expansion method and homogeneous balance principle. The propagation characteristics of soliton wave solutions are analyzed with/without spatial-temporal chirp. It is noteworthy that, by calculating spatial and temporal second-order intensity moment, several novel features of optical beam propagations are obtained, such as stable, oscillating, decaying and blowing up. Additionally, controllability of these solutions with the modulation depth of the parabolic potential is demonstrated. © 2016 Elsevier B.V. (44 refs.)Main Heading: Nonlinear equationsControlled terms: Crack propagation - Solitons - Wave equationsUncontrolled terms: F-expansion method - Homogeneous balance - Optical beam propagation - Parabolic potential - Propagation characteristics - Solitary solutions - Soliton wave solutions - Spatiotemporal solitonsClassification Code: 921.2 CalculusCalculus - 951 Materials ScienceMaterials Science
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Salient Band Selection for Hyperspectral Image Classification via Manifold Ranking
Wang, Qi1; Lin, Jianzhe2; Yuan, Yuan2 Source: IEEE Transactions on Neural Networks and Learning Systems, v 27, n 6, p 1279-1289, June 2016
; ISSN: 2162237X, E-ISSN: 21622388; DOI: 10.1109/TNNLS.2015.2477537; Article number: 7436783;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 School of Computer Science, Center Magery Analysis and Learning, Northwestern Polytechnical University, Xian; 710072, China2 Center for Optical Imagery Analysis and Learning, State Key Laboratory of Transient Optics and Photonics, Chinese Academy of Sciences, Xian; 710119, China
Abstract: Saliency detection has been a hot topic in recent years, and many efforts have been devoted in this area. Unfortunately, the results of saliency detection can hardly be utilized in general applications. The primary reason, we think, is unspecific definition of salient objects, which makes that the previously published methods cannot extend to practical applications. To solve this problem, we claim that saliency should be defined in a context and the salient band selection in hyperspectral image (HSI) is introduced as an example. Unfortunately, the traditional salient band selection methods suffer from the problem of inappropriate measurement of band difference. To tackle this problem, we propose to eliminate the drawbacks of traditional salient band selection methods by manifold ranking. It puts the band vectors in the more accurate manifold space and treats the saliency problem from a novel ranking perspective, which is considered to be the main contributions of this paper. To justify the effectiveness of the proposed method, experiments are conducted on three HSIs, and our method is compared with the six existing competitors. Results show that the proposed method is very effective and can achieve the best performance among the competitors. © 2012 IEEE. (53 refs.)Main Heading: Problem solvingControlled terms: Image classification - Spectroscopy - Vector spacesUncontrolled terms: Band selection - General applications - Hot topics - Hyperspectral image classification - Hyperspectral images - Manifold ranking - Saliency detection - Salient objects
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Dual-clustering-based hyperspectral band selection by contextual analysis
Yuan, Yuan1; Lin, Jianzhe1; Wang, Qi2 Source: IEEE Transactions on Geoscience and Remote Sensing, v 54, n 3, p 1431-1445, March 1, 2016
; ISSN: 01962892; DOI: 10.1109/TGRS.2015.2480866; Article number: 7295589;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 Center for OPTical IMagery Analysis and Learning (OPTIMAL), State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, China2 School of Computer Science and the Center, OPTical IMagery Analysis and Learning (OPTIMAL), Northwestern Polytechnical University, Xi'an, China
Abstract: Hyperspectral image (HSI) involves vast quantities of information that can help with the image analysis. However, this information has sometimes been proved to be redundant, considering specific applications such as HSI classification and anomaly detection. To address this problem, hyperspectral band selection is viewed as an effective dimensionality reduction method that can remove the redundant components of HSI. Various HSI band selection methods have been proposed recently, and the clustering-based method is a traditional one. This agglomerative method has been considered simple and straightforward, while the performance is generally inferior to the state of the art. To tackle the inherent drawbacks of the clustering-based band selection method, a new framework concerning on dual clustering is proposed in this paper. The main contribution can be concluded as follows: 1) a novel descriptor that reveals the context of HSI efficiently; 2) a dual clustering method that includes the contextual information in the clustering process; 3) a new strategy that selects the cluster representatives jointly considering the mutual effects of each cluster. Experimental results on three real-world HSIs verify the noticeable accuracy of the proposed method, with regard to the HSI classification application. The main comparison has been conducted among several recent clustering-based band selection methods and constraint-based band selection methods, demonstrating the superiority of the technique that we present. © 1980-2012 IEEE. (51 refs.)Controlled terms: accuracy assessment - cluster analysis - detection method - experimental study - image analysis - image classification - numerical methodClassification Code: 71.8.5.4 Remote sensing: numerical and image analysisRemote sensing: numerical and image analysis
Database: GEOBASE
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Numerical analysis of pulse signal restoration by stochastic resonance in a buckled microcavity
Sun, Heng1; Liu, Hongjun1; Sun, Qibing1; Huang, Nan1; Wang, Zhaolu1; Han, Jing1 Source: Applied Optics, v 55, n 12, p 3351-3355, April 20, 2016
; ISSN: 1559128X, E-ISSN: 21553165; DOI: 10.1364/AO.55.003351;
Publisher: OSA - The Optical SocietyAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences (CAS), Xi'an; 710119, China
Abstract: A novel scheme is proposed to restore weak pulse signals immersed in noise by stochastic resonance based on photothermal-effect-induced optical bistability in a buckled dome microcavity. The bistable properties of the dome microcavity are analyzed with different initial detuning wavelengths and effective cavity lengths, and bistable transmission can be obtained for input powers in submilliwatt range. A theoretical model is derived to interpret the nonlinear process of pulse signal recovery through double-well potential theory. The cross-correlation coefficient between output signals and pure input pulses is calculated to quantitatively analyze the influence of noise intensity on stochastic resonance. A cross-correlation gain of 7 is obtained, and the noise-hidden signal can be recovered effectively though the buckled dome microcavity with negligible distortion. The simulation results show the potential of using this structure to restore low-level or noise-hidden pulse signals in all-optical integrated systems. © 2016 Optical Society of America. (25 refs.)Main Heading: ResonanceControlled terms: Circuit resonance - Domes - Magnetic resonance - Microcavities - Optical bistability - Restoration - Signal reconstruction - Stochastic systemsUncontrolled terms: Cross correlations - Cross-correlation coefficient - Double-well potential - Integrated systems - Noise intensities - Photothermal effects - Stochastic resonances - Theoretical modelingClassification Code: 408.2 Structural Members and ShapesStructural Members and Shapes - 701.2 Magnetism: Basic Concepts and PhenomenaMagnetism: Basic Concepts and Phenomena - 703.1 Electric NetworksElectric Networks - 714 Electronic Components and TubesElectronic Components and Tubes - 716.1 Information Theory and Signal ProcessingInformation Theory and Signal Processing - 741.1.1 Nonlinear OpticsNonlinear Optics - 931.1 MechanicsMechanics - 961 Systems ScienceSystems Science
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Incoherent ptychography in Fresnel domain with simultaneous multi-wavelength illumination
Pan, An1, 3; Wang, Dong2, 3; Shi, Yi-Shi3, 4; Yao, Bao-Li1; Ma, Zhen1; Han, Yang1, 3 Source: Wuli Xuebao/Acta Physica Sinica, v 65, n 12, June 20, 2016; Language: Chinese
; ISSN: 10003290; DOI: 10.7498/aps.65.124201; Article number: 124201;
Publisher: Institute of Physics, Chinese Academy of SciencesAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China2 Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun; 130033, China3 University of Chinese Academy of Sciences, Beijing; 100049, China4 Academy of Optoelectronics, Chinese Academy of Sciences, Beijing; 100094, China
Abstract: Single wavelength illumination is used in the traditional ptychography. Even though using multi-wavelength to improve image quality, it takes the scheme of illuminating in turn due to the requirement of coherence. So far, the addition of incoherent modes has been regarded as a nuisance in diffractive imaging. Here we propose a scheme of incoherent ptychography and an algorithm of information multiplexing that uses the multi-wavelength illumination simultaneously, which are demonstrated in experiment and simulation. Compared with the scheme of traditional ptychography, it can recover not only the object well, but also the spectral response of the object, probes of complex value and spectral weight of each wavelength respectively. This method obtains much information about the object and owns the multichannel and multispectral merits. Meanwhile, by means of color image coding, this method can retrieve true color images and enhance the image quality. The proposed algorithm has strong robustness. Besides, we also investigate how many modes can be recovered by this method. The work may open up possibilities for information multiplexing in ptychography and multispectral microscopy imaging over various applications. © 2016 Chinese Physical Society. (21 refs.)Main Heading: Image codingControlled terms: Image quality - Iterative methods - MultiplexingUncontrolled terms: Color image coding - Diffractive imaging - Incoherent - Microscopy imaging - Multi-wavelengths - Ptychography - Single wavelength - Strong robustnessClassification Code: 921.6 Numerical MethodsNumerical Methods
Database: Compendex
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Atom decomposition with adaptive basis selection strategy for matrix completion
Hu, Yao1; Zhao, Chen1; Cai, Deng1; He, Xiaofei1; Li, Xuelong2 Source: ACM Transactions on Multimedia Computing, Communications and Applications, v 12, n 3, June 2016
; ISSN: 15516857, E-ISSN: 15516865; DOI: 10.1145/2903716; Article number: 43;
Publisher: Association for Computing MachineryAuthor affiliation: 1 State Key Lab. of CAD and CG, Zhejiang University, 388 Yu Hang Tang Road, Hangzhou, Zhejiang; 310058, China2 Center for OPTical IMagery Analysis and Learning (OPTIMAL), State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, Shaanxi; 710119, China
Abstract: Estimating missing entries in matrices has attracted much attention due to its wide range of applications like image inpainting and video denoising, which are usually considered as low-rank matrix completion problems theoretically. It is common to consider nuclear norm as a surrogate of the rank operator since it is the tightest convex lower bound of the rank operator under certain conditions. However, most approaches based on nuclear norm minimization involve a number of singular value decomposition (SVD) operations. Given a matrix X ∈ Rmxn, the time complexity of the SVD operation is O(mn2), which brings prohibitive computational burden on large-scale matrices, limiting the further usage of these methods in real applications. Motivated by this observation, a series of atom-decomposition-based matrix completion methods have been studied. The key to these methods is to reconstruct the target matrix by pursuit methods in a greedy way, which only involves the computation of the top SVD and has great advantages in efficiency compared with the SVD-based matrix completion methods. However, due to gradually serious accumulation errors, atom-decomposition-based methods usually result in unsatisfactory reconstruction accuracy. In this article, we propose a new efficient and scalable atom decomposition algorithm for matrix completion called Adaptive Basis Selection Strategy (ABSS). Different from traditional greedy atom decomposition methods, a two-phase strategy is conducted to generate the basis separately via different strategies according to their different nature. At first, we globally prune the basis space to eliminate the unimportant basis as much as possible and locate the probable subspace containing the most informative basis. Then, another group of basis spaces are learned to improve the recovery accuracy based on local information. In this way, our proposed algorithm breaks through the accuracy bottleneck of traditional atom-decomposition-based matrix completion methods; meanwhile, it reserves the innate efficiency advantages over SVD-based matrix completion methods. We empirically evaluate the proposed algorithm ABSS on real visual image data and large-scale recommendation datasets. Results have shown that ABSS has much better reconstruction accuracy with comparable cost to atom-decomposition-based methods. At the same time, it outperforms the state-of-the-art SVD-based matrix completion algorithms by similar or better reconstruction accuracy with enormous advantages on efficiency. © 2016 ACM. (47 refs.)Main Heading: Singular value decompositionControlled terms: Algorithms - Atoms - Efficiency - Matrix algebraUncontrolled terms: Accumulation errors - Atom decomposition - Basis selection - Computational burden - Low-rank matrix completions - Matrix completion - Nuclear norm minimizations - Reconstruction accuracyClassification Code: 913.1 Production EngineeringProduction Engineering - 921 MathematicsMathematics - 921.1 AlgebraAlgebra - 931.3 Atomic and Molecular PhysicsAtomic and Molecular Physics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Influence of SiO2layer on the plasmon quenched upconversion luminescence emission of core-shell NaYF4:Yb,Er@SiO2@Ag nanocomposites
Wang, Zhaojin1, 2; Gao, Wei1; Wang, Ruibo1; Shao, Jun1; Han, Qingyan1; Wang, Chi1; Zhang, Jing1; Zhang, Tingting1; Dong, Jun1; Zheng, Hairong1 Source: Materials Research Bulletin, v 83, p 515-521, November 1, 2016
; ISSN: 00255408; DOI: 10.1016/j.materresbull.2016.06.035;
Publisher: Elsevier LtdAuthor affiliation: 1 School of Physics and Information Technology, Shaanxi Normal University, Xi'an; 710119, China2 College of Physics and Optoelectronics Technology, Baoji University of Arts and Sciences, Baoji; 721016, China
Abstract: β-NaYF4:Yb,Er@SiO2@Ag core-shell hybrid nanostructures are prepared and single core-shell hybrid particle is taken to investigate the influence of separation layer on the metal enhanced upconversion luminescence and corresponding mechanism. It is found that the green (4S3/2 → 4I15/2) and red (4F9/2 → 4I15/2) emissions of Er3+increase first and then decrease with the increase of silica shell thickness. The best enhancement is observed at the silica thickness of 12 nm. Time-resolved spectra study shows that the emission enhancement dominates when the silica thickness is 12 nm, which leads to an enhancement factor of 1.28. But the enhancement factor reduces to 0.52 when the silica shell thickness is 5 nm. Here, we define enhancement factor g(ωF) as g(ωF)=IF/I0, IFand I0are fluorescence intensities of UCNPs with emission enhancement and without plasmon enhancement. The luminescence enhancement is owing to the enhanced emission process rather than the excitation process. © 2016 (44 refs.)Main Heading: ErbiumControlled terms: Luminescence - Optical properties - Plasmons - Shells (structures) - Silica - Silver - X ray diffraction - YtterbiumUncontrolled terms: Core-shell hybrid nanostructures - Emission enhancement - Excitation process - Fluorescence intensities - Luminescence enhancements - Plasmon enhancements - Time-resolved spectra - Up-conversion luminescenceClassification Code: 408.2 Structural Members and ShapesStructural Members and Shapes - 547.1 Precious MetalsPrecious Metals - 547.2 Rare Earth MetalsRare Earth Metals - 741.1 Light/OpticsLight/Optics - 931.3 Atomic and Molecular PhysicsAtomic and Molecular Physics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Pulse duration tunable fiber CPA system based on thermally dispersion tuning of chirped fiber bragg grating
Zhang, Xin1; Yang, Zhi1; Li, Qianglong1; Li, Feng1; Yang, Xiaojun1; Wang, Yishan1; Zhao, Wei1 Source: Optik, v 127, n 20, p 8728-8731, October 1, 2016
; ISSN: 00304026; DOI: 10.1016/j.ijleo.2016.06.062;
Publisher: Elsevier GmbHAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision, Mechanics, Chinese Academy of Sciences, Xi'an, 710119, China
Abstract: A pulse width tunable fiber-based chirp pulse amplification (CPA) system had been built by our newly developed dispersion tuning mechanism. In order to realize dispersion fine tuning, we changed the temperature of chirped fiber Bragg grating (CFBG), which was used as stretcher in CPA system, to change the dispersion compensation level between stretcher and grating pairs compressor. By the help of this method, the minimum pulse width after compression can be obtained by balancing the dispersion of the stretcher and of the compressor. In our experimental fiber CPA system, the minimum pulse duration of 780 fs was recorded by autocorrelator during the CFBG temperature tuning at temperature range of 0 °C to 50 °C, and the pulse tuning accuracy can reach about 3 fs/ °C. © 2016 Elsevier GmbH (15 refs.)Main Heading: Ultrashort pulsesControlled terms: Bragg gratings - Dispersion (waves) - Fiber Bragg gratings - Fibers - StretchersUncontrolled terms: CFBG - Chirp pulse amplifications - Chirped fiber Bragg grating - CPA system - Dispersion tuning - Minimum pulse widths - Temperature range - Temperature tuningClassification Code: 462.1 Biomedical Equipment, GeneralBiomedical Equipment, General - 741.3 Optical Devices and SystemsOptical Devices and Systems
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


A robust haze-removal scheme in polarimetric dehazing imaging based on automatic identification of sky region
Zhang, Wenfei1, 2, 3; Liang, Jian1, 3; Ju, Haijuan1, 3; Ren, Liyong1; Qu, Enshi1; Wu, Zhaoxin2 Source: Optics and Laser Technology, v 86, p 145-151, December 1, 2016
; ISSN: 00303992; DOI: 10.1016/j.optlastec.2016.07.015;
Publisher: Elsevier LtdAuthor affiliation: 1 Research Department of Information Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China2 Department of Electronics Science and Technology, School of Electronic & Information Engineering, Xi'an Jiaotong University, Xi'an; 710049, China3 University of Chinese Academy of Sciences, Beijing; 100049, China
Abstract: Quality enhancement of images acquired in hazy conditions is a significant research area in civil and military applications. The polarimetric dehazing methods have been exploited to dehaze hazy images and have proven to be effective in enhancing their quality. In this paper, by combining the polarimetric imaging technique and the dark channel prior technique, a robust haze-removal scheme is presented for the first time. On the one hand, the polarimetric imaging technique has advantages in recovering detailed information well, especially in dense hazy conditions; on the other hand, the dark channel prior technique provides a much more precise and convenient way to estimate the airlight radiance through extracting the sky region automatically. The experiments verify the practicability and effectiveness of the proposed dehazing scheme in quality enhancement of hazy images. Furthermore, comparison study demonstrates that the proposed scheme is superior to some sophisticated methods in terms of the visibility and contrast. We believe this scheme is beneficial in the image dehazing applications, especially for real-time applications. © 2016 Elsevier Ltd (29 refs.)Main Heading: Image processingControlled terms: Automation - Demulsification - Image enhancement - Imaging techniques - Military applications - Military photography - Polarimeters - Quality control - VisibilityUncontrolled terms: Automatic identification - Comparison study - Dark channel priors - Haze removal - Imaging through turbid media - Polarimetric imaging - Quality enhancement - Real-time applicationClassification Code: 404.1 Military EngineeringMilitary Engineering - 731 Automatic Control Principles and ApplicationsAutomatic Control Principles and Applications - 741.2 VisionVision - 746 Imaging TechniquesImaging Techniques - 802.3 Chemical OperationsChemical Operations - 913.3 Quality Assurance and ControlQuality Assurance and Control - 941.3 Optical InstrumentsOptical Instruments
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


A new strategy lung nodules detection algorithm
Qiu, Shi1, 2; Wen, De-Sheng1; Feng, Jun3; Cui, Ying4 Source: Tien Tzu Hsueh Pao/Acta Electronica Sinica, v 44, n 6, p 1413-1419, June 1, 2016; Language: Chinese
; ISSN: 03722112; DOI: 10.3969/j.issn.0372-2112.2016.06.023;
Publisher: Chinese Institute of ElectronicsAuthor affiliation: 1 Xi'an Institute of Optics and Precision Mechanics of CAS, Xi'an; Shaanxi; 710119, China2 University of Chinese Academy of Sciences, Beijing; 100049, China3 School of Information Science and Technology Engineering, Northwestern University, Xi'an; Shaanxi; 710127, China4 College of Equipment Engineering, Engineering University of Chinese Armed Police Force, Xi'an; Shaanxi; 710086, China
Abstract: When lung nodules are detected in lung CT by computers,the vessel cross section and lung nodule have similar imaging characteristics in the two-dimensional CT image sequence,resulting in unable to detect problems precisely.We employed a new strategy for the lung nodules detection algorithm,which is based on the Gestalt psychology.This method can detect lung nodules indirectly by removing blood vessels.The experimental results show that,this algorithm can effectively reduce the influence of blood vessels on lung nodule detection,so as to improve the accuracy of detection of lung nodules. © 2016, Chinese Institute of Electronics. All right reserved. (22 refs.)Main Heading: Biological organsControlled terms: Algorithms - Blood - Blood vessels - Computerized tomography - Signal detectionUncontrolled terms: CT Image - Detection of lung nodules - Gestalt principles - Imaging characteristics - Lung CT - Lung nodule - Lung nodule detection - Lung nodules detectionClassification Code: 461.2 Biological Materials and Tissue EngineeringBiological Materials and Tissue Engineering - 716.1 Information Theory and Signal ProcessingInformation Theory and Signal Processing - 723.5 Computer ApplicationsComputer Applications
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Refractometer probe based on a reflective carbon nanotube-modified microfiber Bragg grating
Jiang, Biqiang1, 2; Xue, Meng1; Zhao, Chenyang1; Mao, Dong1; Zhou, Kaiming2, 3; Zhang, Lin2; Zhao, Jianlin1 Source: Applied Optics, v 55, n 25, p 7037-7041, September 1, 2016
; ISSN: 1559128X, E-ISSN: 21553165; DOI: 10.1364/AO.55.007037;
Publisher: OSA - The Optical SocietyAuthor affiliation: 1 Key Laboratory of Space Applied Physics and Chemistry, Ministry of Education, Shaanxi Key Laboratory of Optical Information Technology, School of Science, Northwestern Polytechnical University, Xi'an; 710072, China2 Aston Institute of Photonic Technologies, Aston University, Birmingham; B4 7ET, United Kingdom3 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China
Abstract: A carbon nanotube (CNT)-modified microfiber Bragg grating (MFBG) is proposed to measure the refractive index with a strong enhancement of the sensitivity in the low refractive index region. The introduction of the CNT layer influences the evanescent field of the MFBG and causes modification of the reflection spectrum. With the increase of the surrounding refractive index (SRI), we observe significant attenuation to the peak of the Bragg resonance, while its wavelength remains almost unchanged. Our detailed experimental results disclose that the CNT-MFBG demonstrates strong sensitivity in the low refractive index range of 1.333-1.435, with peak intensity up to -53.4 dBm/refractive index unit, which is 15-folds higher than that of the uncoated MFBG. Therefore, taking advantage of the CNT-induced evanescent field enhancement, the reflective MFBG probe presents strong sensing capability in biochemical fields. © 2016 Optical Society of America. (30 refs.)Main Heading: Carbon nanotubesControlled terms: Bragg gratings - Evanescent fields - Nanotubes - Probes - Refractive index - YarnUncontrolled terms: Bragg resonance - Field enhancement - Low refractive index - Peak intensity - Probe-based - Reflection spectra - Strong enhancement - Surrounding refractive indices (SRI)Classification Code: 701 Electricity and MagnetismElectricity and Magnetism - 741.1 Light/OpticsLight/Optics - 741.3 Optical Devices and SystemsOptical Devices and Systems - 761 NanotechnologyNanotechnology - 819.4 Fiber ProductsFiber Products
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Optical design of infrared diffractive telescope
Wang, Hao1, 2; Kang, Fu-Zeng1; Zhao, Wei1; Xie, Yong-Jun1 Source: Hongwai Yu Haomibo Xuebao/Journal of Infrared and Millimeter Waves, v 35, n 4, p 425-429, August 1, 2016; Language: Chinese
; ISSN: 10019014; DOI: 10.11972/j.issn.1001-9014.2016.04.008;
Publisher: Chinese Optical SocietyAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China2 University of Chinese Academy of Sciences, Beijing; 100049, China
Abstract: A design example of diffractive telescope is presented and the aperture of objective is 3 meters. The operating wavelength of the system is 7.7~10.3 μm and spectral bandwidth |Δλ/λ| is about 1/3. It is shown that the system approximately attains diffraction limit. We developed a small scale diffractive telescope and its' image quality was perfect. © 2016, Science Press. All right reserved. (5 refs.)Main Heading: TelescopesControlled terms: Diffraction - Optical designUncontrolled terms: Color correction - Diffraction limits - Fresnel lens - Operating wavelength - Small scale - Spectral bandwidthClassification Code: 741.1 Light/OpticsLight/Optics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Deep semantic understanding of high resolution remote sensing image
Qu, Bo1, 2; Li, Xuelong1; Tao, Dacheng3; Lu, Xiaoqiang1 Source: IEEE CITS 2016 - 2016 International Conference on Computer, Information and Telecommunication Systems, August 16, 2016, IEEE CITS 2016 - 2016 International Conference on Computer, Information and Telecommunication Systems; ISBN-13: 9781509034406; DOI: 10.1109/CITS.2016.7546397; Article number: 7546397; Conference: 2016 International Conference on Computer, Information and Telecommunication Systems, CITS 2016, July 6, 2016 - July 8, 2016; Sponsor: State Key Laboratory of Integrated Services Networks (ISN); Xidian University; Yunnan Minzu University;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 Center for OPTical IMagery Analysis and Learning (OPTIMAL), Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, Shaanxi; 710119, China2 University of the Chinese Academy of Sciences, 19A Yuquanlu, Beijing; 100049, China3 Centre for Quantum Computation and Intelligent Systems, Faculty of Engineering and Information Technology, University of Technology Sydney, 81 Broadway Street, Ultimo; NSW; 2007, Australia
Abstract: With the rapid development of remote sensing technology, huge quantities of high resolution remote sensing images are available now. Understanding these images in semantic level is of great significance. Hence, a deep multimodal neural network model for semantic understanding of the high resolution remote sensing images is proposed in this paper, which uses both visual and textual information of the high resolution remote sensing images to generate natural sentences describing the given images. In the proposed model, the convolution neural network is utilized to extract the image feature, which is then combined with the text descriptions of the images by RNN or LSTMs. And in the experiments, two new remote sensing image-captions datasets are built at first. Then different kinds of CNNs with RNN or LSTMs are combined to find which is the best combination for caption generation. The experiments results prove that the proposed method achieves good performances in semantic understanding of high resolution remote sensing images. © 2016 IEEE. (20 refs.)Main Heading: Remote sensingControlled terms: Image reconstruction - SemanticsUncontrolled terms: Convolution neural network - High resolution remote sensing images - Multi-modal neural networks - Remote sensing images - Remote sensing technology - Semantic levels - Semantic understanding - Textual information
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Research on the airborne SINS/CNS integrated navigation system assisted by BD navigation system
Xie, Mei-Lin1; Yang, Xiao-Xu1; Han, Jun-Feng1; Wei, Yu1; Yue, Peng2; Deng, Xiao-Guo1; Huang, Wei1 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 9796, 2016, Selected Papers of the Photoelectronic Technology Committee Conferences held November 2015
; ISSN: 0277786X, E-ISSN: 1996756X; ISBN-13: 9781628418811; DOI: 10.1117/12.2229568; Article number: 97961X; Conference: International Symposia on Atmosphere Optics and Adaptive Optics, Testing and Driving of Laser Fusion Energy Technology, High-performance Special Optical Film Technology, Novel Navigation Technology, Monitoring, Early Warning, Removal Technology of Space Targets and Debris, and UAV Payload Technology, November 15, 2015 - November 28, 2015; Sponsor: Chinese Academy of Engineering; Chinese Society for Optical Engineering; National Natural Science Foundation of China;
Publisher: SPIEAuthor affiliation: 1 Xi'an Institute of Optics and Precision Mechanics, CAS, Xi'an; 710119, China2 Huayin Engineering Test Center, Huayin; 714200, China
Abstract: When the star navigation system working during the day, the strong sky background radiation lead to a result that the detect target light is too weak, in the field of view, because of the limitation on the number of the navigation star, usually choose the single star navigation work mode. In order to improve the reliability of the airborne SINS/CNS integrated navigation system, meet the demand of the long-endurance and high precision navigation, use the tight combination way, single star patrol algorithm to get the position and attitude. There exists filtering divergence problem because of the model error and the system measurement noise is uncertain, put forward a new fuzzy adaptive kalman filtering algorithm. Adjust the size of measurement noise to prevent the filter divergence; the positioning accuracy of integrated navigation system can be improved through BeiDou satellite. Without the information of BeiDou satellite, based on the level of the virtual reference, the navigation precision of integrated navigation system can be ensured over a period of time. © 2016 SPIE. (8 refs.)Main Heading: Adaptive opticsControlled terms: Adaptive filters - Air navigation - Navigation systems - Radio navigation - Space debris - Spurious signal noise - Stars - Tracking (position)Uncontrolled terms: Fuzzy adaptive - Integrated navigation - Noise correction - Single star patrol - Tight combinationClassification Code: 431.5 Air Navigation and Traffic ControlAir Navigation and Traffic Control - 656.1 Space FlightSpace Flight - 657.2 Extraterrestrial Physics and Stellar PhenomenaExtraterrestrial Physics and Stellar Phenomena - 716.3 Radio Systems and EquipmentRadio Systems and Equipment - 741.1 Light/OpticsLight/Optics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Spinning and orbiting motion of particles in vortex beams with circular or radial polarizations
Li, Manman1, 2; Yan, Shaohui1; Yao, Baoli1; Liang, Yansheng1; Zhang, Peng1 Source: Optics Express, v 24, n 18, p 20604-20612, September 5, 2016; E-ISSN: 10944087; DOI: 10.1364/OE.24.020604;
Publisher: OSA - The Optical SocietyAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China2 University of Chinese Academy of Sciences, Beijing; 100049, China
Abstract: Focusing fields of optical vortex (OV) beams with circular or radial polarizations carry both spin angular momentum (SAM) and orbital angular momentum (OAM), and can realize non-axial spinning and orbiting motion of absorptive particles. Using the T-matrix method, we evaluate the optical forces and torques exerted on micro-sized particles induced by the OV beams. Numerical results demonstrate that the particle is trapped on the circle of intensity maxima, and experiences a transverse spin torque along azimuthal direction, a longitudinal spin torque, and an orbital torque, respectively. The direction of spinning motion is not only related to the sign of topological charge of the OV beam, but also to the polarization state. However, the topological charge controls the direction of orbiting motion individually. Optically induced rotations of particles with varying sizes and absorptivity are investigated in OV beams with different topological charges and polarization states. These results may be exploited in practical optical manipulation, especially for optically induced rotations of micro-particles. © 2016 Optical Society of America. (35 refs.)Main Heading: PolarizationControlled terms: Angular momentum - Topology - Torque - Vortex flowUncontrolled terms: Azimuthal direction - Micro-sized particles - Optical manipulation - Orbital angular momentum - Polarization state - Radial polarization - Spin angular momentum - Topological chargesClassification Code: 631.1 Fluid Flow, GeneralFluid Flow, General - 921.4 Combinatorial Mathematics, Includes Graph Theory, Set TheoryCombinatorial Mathematics, Includes Graph Theory, Set Theory - 931.2 Physical Properties of Gases, Liquids and SolidsPhysical Properties of Gases, Liquids and Solids
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Watts-level super-compact narrow-linewidth Tm-doped silica all-fiber laser near 1707 nm with fiber Bragg gratings
Xiao, X.S.1, 2; Guo, H.T.1; Lu, M.1; Yan, Z.J.1; Wang, H.S.1; Wang, Y.S.1; Xu, Y.T.1; Gao, C.X.1; Cui, X.X.1; Guo, Q.1, 2; Peng, B.1 Source: Laser Physics, v 26, n 11, November 2016
; ISSN: 1054660X, E-ISSN: 15556611; DOI: 10.1088/1054-660X/26/11/115103; Article number: 115103;
Publisher: Institute of Physics PublishingAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Science (CAS), Xi'an, Shaanxi; 710119, China2 Graduate School of Chinese Academy of Sciences (CAS), Beijing; 100049, China
Abstract: Watts-level ultra-short wavelength operation of a Tm-doped all fiber laser was developed by using a 1550 nm Er-doped fiber laser pump source and a pair of fiber Bragg gratings (FBGs). The laser yielded 1.28 W of continuous-wave output at 1707.01 nm with a narrow linewidth of ∼44 pm by means of a 20 cm Tm-doped fiber. The dependencies of the slope efficiencies and pump threshold of the Tm-doped fiber laser versus the length of active fiber and reflectivity of the output mirror (FBG) were investigated in detail, in which the maximum average slope efficiency was 36.1%. There is no doubt that this all fiber laser will be a perfect pump source for mid-IR laser output. © 2016 Astro Ltd. (18 refs.)Main Heading: Laser mirrorsControlled terms: Bragg gratings - Efficiency - Fiber Bragg gratings - Fiber lasers - Fibers - Pumping (laser)Uncontrolled terms: All-fiber lasers - Continuous Wave - Er-doped fiber laser - Fiber Bragg gratings (FBGs) - Narrow-line width - Short wavelengths - Slope efficiencies - Tm-doped fiber laserClassification Code: 741.3 Optical Devices and SystemsOptical Devices and Systems - 744.1 Lasers, GeneralLasers, General - 744.4 Solid State LasersSolid State Lasers - 913.1 Production EngineeringProduction Engineering
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Thermal behavior of microchannel cooled high power diode laser arrays
Wu, Dihai1; Zhang, Pu1; Nie, Zhiqiang1; Xiong, Lingling1; Song, Yunfei1, 2; Zhu, Qiwen1; Lu, Yao1, 2; Dang, Yifan1, 2, 3; Liu, Xingsheng1, 3 Source: 2016 17th International Conference on Electronic Packaging Technology, ICEPT 2016, p 499-505, October 4, 2016, 2016 17th International Conference on Electronic Packaging Technology, ICEPT 2016; ISBN-13: 9781509013968; DOI: 10.1109/ICEPT.2016.7583183; Article number: 7583183; Conference: 17th International Conference on Electronic Packaging Technology, ICEPT 2016, August 16, 2016 - August 19, 2016;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, China2 University of Chinese Academy of Sciences, Beijing, China3 Focuslight Technologies Co. LTD, Xi'an, China
Abstract: Heat generation in the active region leads to high junction temperature that significantly affects electrical and optical properties, reliability and lifetime of high power diode laser arrays. It is of great importance to understand the thermal behavior to improve the devices. Compared to conduction cooling techniques, diode laser arrays packaged on microchannel heat sinks have superior capability to dissipate the large amount of heat so as to deliver higher output power and ensure high reliability. In this paper, numerical approach based on finite element method (FEM) and computational fluid dynamics (CFD) was employed to investigate thermal properties of microchannel cooled (MCC) high power diode laser arrays. The static and transient thermal behavior of the devices operated in continuous wave (CW) mode at different water flow rates have been studied in detail. The thermal resistance contributed from the laser chip, solder interface and MCC heat sink was revealed. The correlation between thermal resistance and water flow rate was analyzed. The thermal time constants were derived to characterize the three distinct heating processes related to active region, copper heat sink and copper/water interface. Non-uniformity of junction temperature across the diode laser array was discussed by thermal crosstalk employing the independent emitter analysis. Understanding thermal phenomena in diode laser arrays could offer useful guidelines in optimizing the operating conditions, MCC heat sink structures and packaging architectures for enhanced performance and reliability. © 2016 IEEE. (14 refs.)Main Heading: Semiconductor lasersControlled terms: Computational fluid dynamics - Copper - Crosstalk - Diodes - Electronics packaging - Finite element method - Flow of water - Heat resistance - Heat sinks - Hydraulics - Laser beam welding - Microchannels - Numerical methods - Optical properties - Power semiconductor diodes - Reliability - Thermodynamic propertiesUncontrolled terms: Electrical and optical properties - High-power diode laser arrays - Junction temperatures - Micro channel heat sinks - Optimizing the operating conditions - Performance and reliabilities - Thermal crosstalk - Thermal time constantsClassification Code: 544.1 CopperCopper - 616.1 Heat Exchange Equipment and ComponentsHeat Exchange Equipment and Components - 631.1.1 Liquid DynamicsLiquid Dynamics - 632.1 HydraulicsHydraulics - 641.1 ThermodynamicsThermodynamics - 723.5 Computer ApplicationsComputer Applications - 741.1 Light/OpticsLight/Optics - 744.4.1 Semiconductor LasersSemiconductor Lasers - 744.9 Laser ApplicationsLaser Applications - 921.6 Numerical MethodsNumerical Methods
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


The effects of femtosecond laser processing on the surface accuracy of fibre laser clad sidewalls
Li, R.1, 2; Yang, X.-J.1; Zhao, W.1, 2; He, B.1; Zhao, H.-L.1; Zhu, W.-Y.1 Source: Lasers in Engineering, v 35, n 5-6, p 239-447, 2016
; ISSN: 08981507;
Publisher: Old City PublishingAuthor affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Science, Xi'an; Shaanxi Province; 710119, China2 University of Chinese Academy of Sciences, Beijing; 10004, China
Abstract: To enhance the surface accuracy of laser metal direct forming pieces, a method applying femtosecond laser to fabricate the cladding sidewalls is proposed in this paper. The effects of laser fluence, scanning speed and scanning strategy on the processing accuracy are studied systematically. The experimental results show that when the laser fluence increases, the roughness of cladding sidewalls also increases. The roughness of the cladding sidewall is decreased firstly and then increased with the increasing scanning speed. When the laser fluence is between 0.12 and 0.34 J/cm2, the roughness of cladding sidewall is less than 3 μm. What is more, under single scanning strategy the sidewalls roughness is less than that when back and forth scanning method is used. ©2016 Old City Publishing, Inc. (21 refs.)Main Heading: Laser applicationsControlled terms: Ablation - Cladding (coating) - Fiber lasers - Laser cladding - Scanning - Surface roughness - Ultrafast lasers - Ultrashort pulsesUncontrolled terms: Femtosecond laser processing - Processing accuracies - Rapid manufacturing - Scanning methods - Scanning speed - Scanning strategies - Sidewalls - Surface accuracyClassification Code: 641.2 Heat TransferHeat Transfer - 744 LasersLasers - 931.2 Physical Properties of Gases, Liquids and SolidsPhysical Properties of Gases, Liquids and Solids
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Image recombination transform algorithm for superresolution structured illumination microscopy
Zhou, Xing1, 2; Lei, Ming1; Dan, Dan1; Yao, Baoli1; Yang, Yanlong1; Qian, Jia1; Chen, Guangde2; Bianco, Piero R.3 Source: Journal of Biomedical Optics, v 21, n 9, September 1, 2016
; ISSN: 10833668, E-ISSN: 15602281; DOI: 10.1117/1.JBO.21.9.096009; Article number: 096009;
Publisher: SPIEAuthor affiliation: 1 Chinese Academy of Sciences, Xi'An Institute of Optics and Precision Mechanics, State Key Laboratory of Transient Optics and Photonics, No. 17 Xinxi Road, Xi'an, Shaanxi; 710119, China2 Xi'An Jiaotong University, School of Science, No. 28 Xianning West Road, Xi'an, Shaanxi; 710049, China3 University at Buffalo, Department of Microbiology and Immunology, No. 12 Capen Hall, Buffalo; NY; 14214, United States
Abstract: Structured illumination microscopy (SIM) is an attractive choice for fast superresolution imaging. The generation of structured illumination patterns made by interference of laser beams is broadly employed to obtain high modulation depth of patterns, while the polarizations of the laser beams must be elaborately controlled to guarantee the high contrast of interference intensity, which brings a more complex configuration for the polarization control. The emerging pattern projection strategy is much more compact, but the modulation depth of patterns is deteriorated by the optical transfer function of the optical system, especially in high spatial frequency near the diffraction limit. Therefore, the traditional superresolution reconstruction algorithm for interference-based SIM will suffer from many artifacts in the case of projection-based SIM that possesses a low modulation depth. Here, we propose an alternative reconstruction algorithm based on image recombination transform, which provides an alternative solution to address this problem even in a weak modulation depth. We demonstrated the effectiveness of this algorithm in the multicolor superresolution imaging of bovine pulmonary arterial endothelial cells in our developed projection-based SIM system, which applies a computer controlled digital micromirror device for fast fringe generation and multicolor light-emitting diodes for illumination. The merit of the system incorporated with the proposed algorithm allows for a low excitation intensity fluorescence imaging even less than 1W/cm2, which is beneficial for the long-term, in vivo superresolved imaging of live cells and tissues. © 2016 The Authors. (35 refs.)Main Heading: Optical resolving powerControlled terms: Diffraction - Endothelial cells - Fluorescence - Laser beams - Light emitting diodes - Modulation - Optical systems - Optical transfer function - PolarizationUncontrolled terms: Arterial endothelial cells - Digital micro-mirror device - Multicolor light-emitting diodes - Structured illumination - Structured illumination microscopies (SIM) - Structured illumination microscopy - Super resolution - Super-resolution reconstructionClassification Code: 461.9 BiologyBiology - 714.2 Semiconductor Devices and Integrated CircuitsSemiconductor Devices and Integrated Circuits - 741.1 Light/OpticsLight/Optics - 741.3 Optical Devices and SystemsOptical Devices and Systems - 744.8 Laser Beam InteractionsLaser Beam Interactions
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Mode Splitter Without Changing the Mode Order in SOI Waveguide
Liao, Jianwen1, 2, 3; Zhang, Lingxuan1, 2, 3; Liu, Mulong1, 2, 3; Wang, Leiran1, 2; Wang, Weiqiang1, 2; Wang, Guoxi1, 2; Ruan, Chi1; Zhao, Wei1, 2; Zhang, Wenfu1, 2 Source: IEEE Photonics Technology Letters, v 28, n 22, p 2597-2600, November 15, 2016
; ISSN: 10411135; DOI: 10.1109/LPT.2016.2606496;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China2 China-U.K. Joint Research Center on Micro/Nano Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China3 University of Chinese Academy of Sciences, Beijing; 101408, China
Abstract: We proposed a mode splitter based on directional coupler (DC), which is capable of splitting the TE0and TE1modes without changing the mode order. It is found that high coupling efficiency (higher than-1 dB), low mode crosstalk (less than-16 dB), wide bandwidth (~100 nm), and large fabrication tolerance (±10 nm) can be obtained by a 24.4 μm coupling length DC structure, which is composed of a strip and a slot silicon waveguide. This design represents a first step toward mode splitter without changing the mode order, which can find important potential applications, such as optical isolation and mode division multiplexing (MDM), in large-scale photonic integrated circuits (PICs). © 1989-2012 IEEE. (18 refs.)Main Heading: WaveguidesControlled terms: Directional couplers - Optical waveguidesUncontrolled terms: Coupling efficiency - Fabrication tolerances - Mode splitter - Mode-division multiplexing - Optical isolation - Photonic integrated circuits - Silicon waveguide - Slot waveguideClassification Code: 714.3 WaveguidesWaveguides
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


SURF and KPCA based image perceptual hashing algorithm
Qi, Yinlong1, 2; Qiu, Yuehong1 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 10033, 2016, Eighth International Conference on Digital Image Processing, ICDIP 2016
; ISSN: 0277786X, E-ISSN: 1996756X; ISBN-13: 9781510605039; DOI: 10.1117/12.2244291; Article number: 100332K; Conference: 8th International Conference on Digital Image Processing, ICDIP 2016, May 20, 2016 - May 23, 2016; Sponsor: Chengdu University of Information Technology; Chinese Academy of Sciences Chengdu Institute of Computer Applications; International Association of Computer Science and Information Technology; Sichuan Province Computer Federation;
Publisher: SPIEAuthor affiliation: 1 Xi'An Institute of Optics and Precision Mechanics of CAS, Xi'an; 710119, China2 University of Chinese Academy of Sciences, Beijing; 100049, China
Abstract: Image perceptual hashing is a notable concept in the field of image processing. Its application ranges from image retrieval, image authentication, image recognition, to content-based image management. In this paper a novel image hashing algorithm based on SURF and KPCA, which extracts speed-up robust feature as the perceptual feature, is proposed. SURF retains the robust properties of SIFT, and it is 3 to 10 times faster than SIFT. Then, the Kernel PCA is used to decompose key points' descriptors and get compact expressions with well-preserved feature information. To improve the precision of digest matching, a binary image template of input image is generated which contains information of salient region to ensure the key points in it have greater weight during matching. After that, the hashing digest for image retrieval and image recognition is constructed. Experiments indicated that compared to SIFT and PCA based perceptual hashing, the proposed method could increase the precision of recognition, enhance robustness, and effectively reduce process time. © 2016 SPIE. (8 refs.)Main Heading: Image processingControlled terms: Image matching - Image recognition - Image retrievalUncontrolled terms: Kernel PCA - Perceptual hashing - Robust hashing - Salient region detections - SURF
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


On-chip generation of four-photon entangled qubit states
Reimer, Christian1; Kues, Michael1; Roztocki, Piotr1; Caspani, Lucia1, 2; Bromberg, Yaron3; Wetzel, Benjamin1; Little, Brent E.4; Chu, Sai T.5; Moss, David J.1, 6; Morandotti, Roberto1 Source: 2016 Conference on Lasers and Electro-Optics, CLEO 2016, December 16, 2016, 2016 Conference on Lasers and Electro-Optics, CLEO 2016; ISBN-13: 9781943580118; Article number: 7787592; Conference: 2016 Conference on Lasers and Electro-Optics, CLEO 2016, June 5, 2016 - June 10, 2016;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 INRS-EMT, 1650 Boulevard Lionel-Boulet, Varennes; QC; J3X 1S2, Canada2 School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh; EH14 4AS, United Kingdom3 Department of Applied Physics, Yale University, New Haven; CT; 06520, United States4 Xi'An Institute of Optics and Precision Mechanics of CAS, Xi'an, China5 Department of Physics and Material Science, City University of Hong Kong, Tat Chee Avenue, Hong Kong, Hong Kong6 Centre for Micro Photonics, Swinburne University of Technology, Hawthorne; VIC; 3122, Australia
Abstract: We demonstrate four-photon entangled qubits generated from an integrated quantum frequency comb source. This is confirmed by four-photon quantum interference with a visibility above 89%, and quantum state tomography revealing a fidelity above 64%. © 2016 OSA. (13 refs.)
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Mode-order-invariant beam splitter on silicon-on-insulator waveguide
Liao, Jianwen1; Wang, Guoxi1; Zhang, Wenfu2 Source: IEEE International Conference on Group IV Photonics GFP, 2016-November, p 143-144, November 8, 2016, 2016 IEEE 13th International Conference on Group IV Photonics, GFP 2016
; ISSN: 19492081; ISBN-13: 9781509019038; DOI: 10.1109/GROUP4.2016.7739134; Article number: 7739134; Conference: 13th IEEE International Conference on Group IV Photonics, GFP 2016, August 24, 2016 - August 26, 2016; Sponsor: Intel; Luceda Photonics; Lumerical Solutions, Inc.; Synopsys Inc.;
Publisher: IEEE Computer SocietyAuthor affiliation: 1 Xi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, China2 College of Materials Science and Opto-electric Technology, University of Chinese Academy of Sciences, China
Abstract: We present a mode splitter which is able to split the TE0&TE1modes without changing the mode order. High coupling efficiency (>-2 dB), low insertion loss (<-0.1 dB) and good fabrication tolerance (-40 nm<Δw<70 nm) can be obtained over a wide bandwidth of 150 nm. © 2016 IEEE. (4 refs.)Main Heading: PhotonicsControlled terms: Directional couplers - Optical waveguides - Silicon on insulator technologyUncontrolled terms: Coupling efficiency - Fabrication tolerances - Invariant beams - Low insertion loss - Mode splitter - On-chip optical interconnects - Silicon on insulator waveguide - Silicon photonicsClassification Code: 714.2 Semiconductor Devices and Integrated CircuitsSemiconductor Devices and Integrated Circuits - 714.3 WaveguidesWaveguides - 741.1 Light/OpticsLight/Optics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Four mode multi-correlated bi-photon states within an integrated quantum frequency comb
Kues, Michael1; Reimer, Christian1; Wetzel, Benjamin1; Roztocki, Piotr1; Caspani, Lucia1, 2; Bromberg, Yaron3; Little, Brent E.4; Munro, William J.5; Chu, Sai T.6; Moss, David J.1, 7; Morandotti, Roberto1 Source: 2016 Conference on Lasers and Electro-Optics, CLEO 2016, December 16, 2016, 2016 Conference on Lasers and Electro-Optics, CLEO 2016; ISBN-13: 9781943580118; Article number: 7787513; Conference: 2016 Conference on Lasers and Electro-Optics, CLEO 2016, June 5, 2016 - June 10, 2016;
Publisher: Institute of Electrical and Electronics Engineers Inc.Author affiliation: 1 INRS-EMT, 1650 Boulevard Lionel-Boulet, Varennes; QC; J3X 1S2, Canada2 School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh; EH14 4AS, United Kingdom3 Department of Applied Physics, Yale University, New Haven; CT; 06520, United States4 Xi'An Institute of Optics and Precision Mechanics of CAS, Xi'an, China5 NTT Basic Research Laboratories, NTT Corporation, 3-1 Morinosato-Wakamiya, Atsugi, Kanagawa; 243-0198, Japan6 Department of Physics and Material Science, City University of Hong Kong, Tat Chee Avenue, Hong Kong, Hong Kong7 Centre for MicroPhotonics, Swinburne University of Technology, Hawthorne; VIC; 3122, Australia
Abstract: The generation of two-photon multi-correlated states over four modes and their pairwise entanglement is demonstrated by superimposing two different spontaneous four-wave mixing processes inside a bi-modally pumped CMOS-compatible microring resonator. © 2016 OSA. (10 refs.)
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Topology optimization design of space rectangular mirror
Qu, Yanjun1, 2; Wang, Wei1; Liu, Bei1, 2; Li, Xupeng1, 2 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 10154, 2016, Advanced Optical Design and Manufacturing Technology and Astronomical Telescopes and Instrumentation
; ISSN: 0277786X, E-ISSN: 1996756X; DOI: 10.1117/12.2247396; Article number: 1015421; Conference: International Symposium on Advanced Optical Design and Manufacturing Technologies and International Symposium on Astronomical Telescope and Instrumentation, May 9, 2016 - May 11, 2016; Sponsor: China High-Tech Industrialization Association (CHIA); Chinese Society for Optical Engineering (CSOE);
Publisher: SPIEAuthor affiliation: 1 Xi'an Institute of Optics and Precision Mechanics of CAS, Xi'an, Shaanxi; 710068, China2 University of Chinese Academy of Sciences, Beijing; 100049, China
Abstract: A conceptual lightweight rectangular mirror is designed based on the theory of topology optimization and the specific structure size is determined through sensitivity analysis and size optimization in this paper. Under the load condition of gravity along the optical axis, compared with the mirrors designed by traditional method using finite element analysis method, the performance of the topology optimization reflectors supported by peripheral six points are superior in lightweight ratio, structure stiffness and the reflective surface accuracy. This suggests that the lightweight method in this paper is effective and has potential value for the design of rectangular reflector. © 2016 SPIE. (12 refs.)Main Heading: Finite element methodControlled terms: Manufacture - Mirrors - Optical design - Radio telescopes - Reflection - Sensitivity analysis - Shape optimization - Telescopes - TopologyUncontrolled terms: Finite element analysis method - Lightweight - Load condition - Potential values - Reflective surfaces - Size optimization - Structure sizes - Structure stiffnessClassification Code: 537.1 Heat Treatment ProcessesHeat Treatment Processes - 657.2 Extraterrestrial Physics and Stellar PhenomenaExtraterrestrial Physics and Stellar Phenomena - 741.1 Light/OpticsLight/Optics - 741.3 Optical Devices and SystemsOptical Devices and Systems - 921 MathematicsMathematics
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Alignment method of off-axis RC reflective optical system
Zhang, Xue-Min1, 2; Xing, Song1; Zhang, Zhi-Jun1; Hou, Xiao-Hua1 Source: Proceedings of SPIE - The International Society for Optical Engineering, v 9682, 2016, 8th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Large Mirrors and Telescopes
; ISSN: 0277786X, E-ISSN: 1996756X; ISBN-13: 9781628419177; DOI: 10.1117/12.2245135; Article number: 968218; Conference: 8th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Large Mirrors and Telescopes, AOMATT 2016, April 26, 2016 - April 29, 2016; Sponsor: Chinese Academy of Sciences, Institute of Optics and Electronics (IOE); The Chinese Optical Society (COS);
Publisher: SPIEAuthor affiliation: 1 Axi'An Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an; 710119, China2 Graduate University of Chinese Academy of Sciences, Beijing; 100049, China
Abstract: Off-axis optical system has a wide application in space optics and remote detective area. The high surface shape accuracy can be ensured with the development of advanced manufacture technique. So the only condition which limits the wide application of off-axis optical system is how to realize the precise alignment of it. Based on a RC reflective optical system whose diameter is 400mm, the alignment method which combines the high resolution initial placement and computer-aided alignment is introduced. By designing a system which can measure the off-axis fabrication and off-axis angle precisely, the high resolution initial placement of off-axis mirror can be ensured with a measurement accuracy of ±0.05mm and ±10". The good initial placement can give a good initial state, so the computer-aided model can be converged well. The experiment shows that a system which has a good initial placement could have a good wave aberration of 0.04λ after three times iteration adjustment. © 2016 SPIE. (11 refs.)Main Heading: Optical systemsControlled terms: Alignment - Iterative methods - Manufacture - Mirrors - Optical testing - TelescopesUncontrolled terms: Alignment methods - Computer aided modeling - Computer-aided alignment - Initial placement - Measurement accuracy - Off-axis - Precise alignments - Reflective optical systemClassification Code: 537.1 Heat Treatment ProcessesHeat Treatment Processes - 601.1 Mechanical DevicesMechanical Devices - 741.3 Optical Devices and SystemsOptical Devices and Systems - 921.6 Numerical MethodsNumerical Methods
Database: Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.


Dynamics analysis of microsphere in a dualbeam fiber-optic trap with transverse offset
Chen, Xinlin1; Xiao, Guangzong1, 2; Luo, Hui1; Xiong, Wei1; Yang, Kaiyong1 Source: Optics Express, v 24, n 7, p 7575-7584, April 4, 2016; E-ISSN: 10944087; DOI: 10.1364/OE.24.007575;
Publisher: OSA - The Optical SocietyAuthor affiliation: 1 College of Optoelectronic Science and Engineering, National University of Defense Technology, Changsha, China2 State Key Laboratory of Transient Optics and Photonic, Chinese Academy of Sciences, Xian, China
Abstract: A comprehensive dynamics analysis of microsphere has been presented in a dual-beam fiber-optic trap with transverse offset. As the offset distance between two counterpropagating beams increases, the motion type of the micro