2023

• Record 421 of
  
  Title:Underwater Polarization Image Restoration Method Using Optimal Multi-Parameters Reconstruction
  
  Author(s):Chen, Xiongfeng(1,2); Ruan, Chi(1)
  Source: Binggong Xuebao/Acta Armamentarii  Volume: 44  Issue: 7  Article Number: null  DOI: 10.12382/bgxb.2022.0343  Published: July 30, 2023  
  Abstract:Underwater imaging in high turbidity conditions often suffers from issues such as low resolution, reduced contrast, and overall poor image quality. Classical methods for underwater image polarization restoration require the selection of a background point without any target, making them inapplicable in certain scenarios. In order to solve this problem, the method of underwater polarization image restoration based on optimal multi-parameter reconstruction is proposed. Based on the classical underwater imaging physical model, the transmittance is divided into absorption and backscattering coefficients. By calculating the polarization degree of the underwater image using the Stokes vector, two target points are selected. The optimal reconstruction values of reflectivity, absorption coefficient and backscattering coefficient of two target points are obtained by optimizing the restored image. By using the optimized parameters to remove the backscattered light and recover the signal light lost due to absorption from the underwater image, the polarization restoration of the underwater image is realized. Two no-reference image quality assessment indexes are employed as quantitative indexes. Compared with other methods, experiments based on different turbidity and different targets show that this method can effectively restore the degraded underwater image, especially in the case of high turbidity. This method is expected to be applied to enhance optical imaging clarity of underwater vehicles and facilitate subsequent target detection. © 2023 China Ordnance Society. All rights reserved.
  Accession Number: 20233314554392
• Record 422 of
  
  Title:Research on Delay Line Anode Photon Counting Imaging Detector
  
  Author(s):Zhang, Yalong(1,2); Liu, Yongan(1); Zhang, Ruili(1); Yang, Xianghui(1); Liu, Zhe(1); Sheng, Lizhi(1)
  Source: Guangzi Xuebao/Acta Photonica Sinica  Volume: 52  Issue: 12  Article Number: 1204001  DOI: 10.3788/gzxb20235212.1204001  Published: December 2023  
  Abstract:A useful technique for detecting very faint light is photon counting technology，which has numerous potential applications in high-energy physics，astronomical detection，quantum key distribution systems， and high-resolution spectral measurement. The micro-channel plate based single-photon counting detector benefits from being small and compact in design. While counting photons，it can precisely record the arrival time and location information by combining with the position-sensitive anode. The detector based on microchannel plate and position-sensitive anode has high sensitivity and time and space discrimination ability，and has been widely used in various fields. Firstly，we investigated position-sensitive anodes for imaging，there are many position-sensitive anodes for imaging. Among which the spatial resolution of WSA anodes decreases gradually with the increase of detection area；the electronics design of MAMA anodes becomes more complex as the detection area increases；each strip of XS anode requires an independent readout electronics，resulting in higher circuit power consumption；the spatial resolution of delay line anodes is much better than that of other kinds of position-sensitive anodes because it is not impacted by the detecting area. Therefore，a novel two-dimensional cross delay line anode based on a printed circuit board was proposed after the delay line anode single photon detector's operating principle was examined. The anode adopts a multi-layer structure design，from top to bottom including an upper collection unit，a reference ground，a lower collection unit，a reference ground，a collection unit and a delay unit through the via connection to achieve signal transmission. Compared to traditional anode designs，this design places the delay unit on the back of the collection unit，making it more miniaturized. Secondly，the high resistance sensor layer was replaced of an anode to capture electrons based on the charge induction readout technology. Due to the characteristics of high resistance of sensor layer，when the electron cloud reaches the charge induction layer，it takes a certain time to diffuse to the ground，so an equal amount of induced charge is generated on the other side，and the position-sensitive anode senses the induced charge and performs analytical imaging on it. Compared with the traditional direct collection method，the direct collection is easy to cause the redistribution of secondary electrons on the anode，resulting in the instability of the output image. Charge induction technology effectively avoids these problems and eliminates the influence of non-uniform electron field on electron motion，it provides convenience for the development of vacuum package detector，which not only reduces the difficulty of device manufacturing，but also facilitates testing. Finally，a set of experimental system is used to test the delay line anode，the developed signal readout circuit mainly includes time digital conversion circuit and photon arrival timing circuit，and imaging is realized by signal discrimination and photon arrival timing circuit. According to the test results，the detector's ideal spatial resolution is 107 μm and its ideal dark count is 0.23 count/（cm2·s）. The innovative cross delay line anode has created the groundwork for single photon image detection in large area arrays，it provides theoretical guidance for further performance improvement. © 2023 Chinese Optical Society. All rights reserved.
  Accession Number: 20240815582121
• Record 423 of
  
  Title:Reconstruction of structured illumination microscopy with an untrained neural network
  
  Author(s):Liu, Xin(1); Li, Jinze(2); Fang, Xiang(1); Li, Jiaoyue(1); Zheng, Juanjuan(1,3); Li, Jianlang(1); Ali, Nauman(1); Zuo, Chao(1,4); Gao, Peng(1); An, Sha(1)
  Source: Optics Communications  Volume: 537  Issue: null  Article Number: 129431  DOI: 10.1016/j.optcom.2023.129431  Published: June 15, 2023  
  Abstract:Structured illumination microscopy (SIM) is one of super-resolution optical microscopic techniques, and it has been widely used in biological research. In this paper, a physics-driven deep image prior framework for super-resolution reconstruction of SIM (entitled DIP-SIM) is proposed. DIP-SIM does not rely on a large number of labeled data, and the output becomes more interpretable due to the intrinsic constraint of a physical model. Both the simulation and experiment verify that DIP-SIM can reconstruct a super-resolution image with a quality comparable to conventional SIM. Of note, it allows for super-resolution reconstruction from three raw images for two-orientation SIM and four raw images for three-orientation SIM, and hence it has a much faster imaging speed and lower photobleaching compared with the traditional SIM. We can envisage that the proposed method can be applied to chemistry and biomedical fields, etc. © 2023 Elsevier B.V.
  Accession Number: 20231313804280
• Record 424 of
  
  Title:High performance infrared selective emissivity film tailored for thermal-stable camouflage
  
  Author(s):Kang, Yifan(1,2,3); Yang, Hongtao(1); Wang, Cheng(3); Fan, Qi(3); Lei, Xiaomei(3); Zhang, Haifang(3); Zhu, Guanfang(3); Wang, Chao(4)
  Source: Optics Communications  Volume: 546  Issue: null  Article Number: 129743  DOI: 10.1016/j.optcom.2023.129743  Published: November 1, 2023  
  Abstract:A polarization-independent broadband infrared selective absorber/emitter (ISAE) based on multilaminar architecture is proposed and demonstrated. The salient features are that it has both low average emissivity of less than 0.1 in two atmospheric windows (3–5μm and 8–14μm) and otherwise high average emissivity of more than 0.8 in two non-atmospheric windows (2.5–3μm and 5–8μm), which renders it tailored infrared camouflage performance with thermal stability. Meanwhile, there is sharp narrowband absorption around at 10.6μm, which allows it to additionally possess laser camouflage performance. The comprehensive dependence of multispectral selective emissivity properties on the structural parameters, the polarization and incident angle of incoming excitation are analyzed and the underlying physical mechanisms are explored. It is found that the selective absorption/emissivity in band 5–8μm is originated from the fundamental mode plasmonic resonances, while that in 2.5–5μm is originated from the high-order hybrid mode plasmonic resonances therein. Meanwhile, there does exist a coupled competition effect between the hybrid modes in 2.5–3μm and in 3–5μm. All the results construct the basic guideline for designing these kinds of ISAE materials. Furthermore, we reexamine the physical essence of infrared camouflage based on multispectral bands selective emissivity with thermal management and establish an optimized generalized method for evaluating the camouflage performance of ISAE. The proposed ISAE proves to have much better infrared camouflage property throughout 2.5–14μm than the existing designs reported. The proof-of-principle ISAE is prepared and the selective emission spectrum is characterized, which is in good agreement with the simulations. © 2023 Elsevier B.V.
  Accession Number: 20233014448518
• Record 425 of
  
  Title:Tailoring of the femtosecond-laser-induced damage properties and hydrolysis resistance of fluoroaluminate glass
  
  Author(s):Yang, Yuze(1,2); Li, Xianda(1,2); Guo, Chen(1,2); Wang, Pengfei(1,2)
  Source: Ceramics International  Volume: 49  Issue: 14  Article Number: null  DOI: 10.1016/j.ceramint.2023.04.166  Published: July 15, 2023  
  Abstract:In this study, we investigated and compared the hydrolysis resistance properties of three different types of fluoride glasses and their damage characteristics induced by an 800 nm fs (fs) laser. The results show that the hydrolysis resistance of the fluoroaluminate (AYF) glass is significantly higher than that of the fluorozirconate (ZBLAN) and the fluoroindate (IZBS) glass. After soaking in distilled water for 7 days, the average transmittance of the fluoroaluminate glass (AYF) remains around 80% in the range of 2–6 μm, while that of the other two glasses decrease to zero at the hydroxyl group absorption wavelength of ∼2.96 μm. After 24 h of immersion, the mass loss rate of AYF glass is less than one-eleventh of ZBLAN glass and one-eighth of IZBS glass, respectively. Under the irradiation of fs laser (800 nm, 91 fs, 1 kHz), the "1-on-1″ mode laser-induced damage threshold of the AYF glass is as high as 5164.9 mJ/cm2, which is 80.3% higher than that of the IZBS glass (2863.3 mJ/cm2) and 16.8% higher than that of the ZBLAN glass (4420.1 mJ/cm2). The higher laser damage threshold is attributed to the relative larger optical bandgap and higher Al–F energies of the AYF glass. Using this mechanism, we further tailored the fluoroaluminate glass's optical bandgap increased and the accumulation rate of electrons decreased by introducing up to 20 mol % TeO2 into the AYF glass, finally the fs laser-induced damage threshold of the corresponding sample with 20 mol % TeO2 increased by about 79.5% to the maximum 9272.2 mJ/cm2, compared with the TeO2-free AYF sample. © 2023 Elsevier Ltd and Techna Group S.r.l.
  Accession Number: 20231714024863
• Record 426 of
  
  Title:Gibbs-Wulff optical vortex array
  
  Author(s):Qin, Xue-Yun(1); Zhu, Liu-Hao(1); Hu, Hua-Jie(1); Tai, Yu-Ping(1,2); Li, Xin-Zhong(1,2)
  Source: Journal of Applied Physics  Volume: 133  Issue: 1  Article Number: 013101  DOI: 10.1063/5.0133068  Published: January 7, 2023  
  Abstract:Optical vortex array (OVA) containing multiple optical vortices is an optimal candidate for applications of optical communications, complex manipulation of multi-particle systems, and mass-synchronous fabrication. However, the existing OVAs have not been constructed to respond to the application requirements, particularly for micro-/nanomaterial fabrication where the boundary, size, and stability need to be carefully considered. To address this issue, we propose a Gibbs-Wulff OVA (GWOVA) by analogizing the Gibbs-Wulff theorem in solid-state physics. Herein, the Gibbs-Wulff theorem is first generalized to OVA's generation as the condition to confine its growth boundary. The GWOVA, which possesses versatile structures and arrangement modes (simple- and close-packed modes), is successfully generated and grown. It exhibits high stability and perfect symmetry during growth and rotation, which satisfies the symmetric group of D2s. Owing to its stable structure and growth boundary conditions, the GWOVA has great potential for a wide range of applications, particularly in micro-/nanomaterial fabrication. © 2023 Author(s).
  Accession Number: 20230213371598
• Record 427 of
  
  Title:When optical vortex array meets cycloid
  
  Author(s):Ma, Xin(1); Hu, Huajie(1); Tai, Yuping(1,2); Li, Xinzhong(1,2)
  Source: Optics Express  Volume: 31  Issue: 7  Article Number: null  DOI: 10.1364/OE.484830  Published: March 27, 2023  
  Abstract:Optical vortex arrays (OVAs) have drawn widespread attention owing to their multiple optical vortices and higher dimensions. However, existing OVAs have not yet been utilized to exploit the synergy effect as an entire system, particularly for manipulating multiple particles. Thus, the functionality of OVA should be explored to respond to application requirements. Hence, this study proposes a functional OVA, called cycloid OVA (COVA), based on a combination of cycloid and phase-shift techniques. By modifying the cycloid equation, multiple structural parameters are designed to modulate the structure of the COVAs. Subsequently, versatile and functional COVAs are experimentally generated and modulated. In particular, COVA executes local dynamic modulation, whereas the entire structure remains unchanged. Further, the optical gears are first designed using two COVAs, which exhibit potential for transferring multiple particles. Essentially, OVA is endowed the characteristics and capacity of the cycloid when they meet. This work provides an alternative scheme to generate OVAs, which will open up advanced applications for the complex manipulation, arrangement and transfer of multiple particles. © 2023 Optica Publishing Group.
  Accession Number: 20231313797642
• Record 428 of
  
  Title:Cycloid-structured optical tweezers
  
  Author(s):Wei, Wenjun(1); Zhu, Liuhao(1); Tai, Yuping(1,2); Li, Xinzhong(1,2)
  Source: Optics Letters  Volume: 48  Issue: 4  Article Number: null  DOI: 10.1364/OL.482437  Published: February 15, 2023  
  Abstract:We designed novel cycloid-structured optical tweezers based on a modified cycloid and holographic shaping techniques. The optical tweezers realize all the dynamic characteristics of the trapped particles, including start, stop, and variable-velocity motions along versatile trajectories. The superiority of the tweezers is experimentally verified using polystyrene micro-sphere manipulation. This work provides a novel platform for more complex manipulations of particles. © 2023 Optica Publishing Group.
  Accession Number: 20230713583708
• Record 429 of
  
  Title:Femtosecond Yb-doped tapered fiber pulse amplifiers with peak power of over hundred megawatts
  
  Author(s):Cao, Xue(1,2,3); Li, Qianglong(1,2,3); Li, Feng(1); Zhao, Hualong(1); Zhao, Wei(1); Wang, Yishan(1); Li, Dongjuan(1); Yang, Yang(1); Wen, Wenlong(1); Si, Jinhai(2)
  Source: Optics Express  Volume: 31  Issue: 4  Article Number: null  DOI: 10.1364/OE.480637  Published: February 1, 2023  
  Abstract:Ultrafast fiber lasers combining high peak power and excellent beam quality in the 1-μm wavelength range have been explored to applications in industry, medicine and fundamental science. Here, we report generation of a high-energy sub 300 fs polarization maintaining fiber chirped pulse amplification (CPA) system by using a Yb-doped large mode area tapered polarization maintaining (PM) optical fiber with the core/cladding diameters of 35/250 μm at the thin end and 56/400 μm at the thick end. The taper fiber design features a confined core for selective gain amplification and multi-layer cladding for enhanced suppression of higher order modes. In this regime, we have demonstrated 266 fs pulse amplification with peak power of up to 132 MW at a repetition rate of 2 MHz and high beam quality with measured M2 value of 1.1∼1.3. To the best of our knowledge, it is the highest peak power reported in such tapered Yb-doped fiber (T-YDF) amplifier in the femtosecond regime. This work indicates the great potential of the T-YDF to realize further power scaling, high laser efficiency, and excellent beam quality in high-power femtosecond fiber lasers. © 2023 Optica Publishing Group.
  Accession Number: 20230613553610
• Record 430 of
  
  Title:Fingerprint terahertz spectroscopy combined with machine learning for multicomponent mixture analysis
  
  Author(s):Yan, Hui(1,2,3); Fan, Wen-Hui(1,3,4); Qin, Chong(1,3); Jiang, Xiao-Qiang(1,3); Zhang, Yu-Ming(1,3)
  Source: Vibrational Spectroscopy  Volume: 128  Issue: null  Article Number: 103581  DOI: 10.1016/j.vibspec.2023.103581  Published: September 2023  
  Abstract:The distinctive vibrational features in terahertz (THz) spectroscopy characterize a "fingerprint" of the single-component molecular substance. However, due to componential spectral overlapping and baseline drift, the identification and quantification of multicomponent mixtures are quite challenging for THz spectral analysis. A systematic and feasible strategy has been proposed by combining machine learning with THz spectroscopy for both qualitative and quantitative analysis. After the component number was effectively determined by singular value decomposition (SVD), nonnegative matrix factorization (NMF) and self-modeling mixture analysis (SMMA) were applied to extract componential THz spectra. The difficulties of NMF and SMMA encountered in handling ternary mixtures were solved. The results show component spectra extracted by SMMA are highly consistent with the experimental spectra of pure substances after standardization to correct baseline drift, which greatly facilitates rapid identification of compositions in mixtures. Additionally, compared to back-propagation neural network (BPNN), support vector regression (SVR) predict the contents of each individual component with high robustness and the decision coefficient R2 greater than 0.949. Fingerprint terahertz spectroscopy enhanced by machine learning provided an effective strategy for mixture analysis in practical applications. © 2023 Elsevier B.V.
  Accession Number: 20233414588605
• Record 431 of
  
  Title:Spectral Token Guidance Transformer for Multisource Images Change Detection
  
  Author(s):Sun, Bangyong(1,2); Liu, Qinsen(1); Yuan, Nianzeng(1); Tan, Jiahai(3,4); Gao, Xiaomei(5); Yu, Tao(6)
  Source: IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing  Volume: 16  Issue: null  Article Number: null  DOI: 10.1109/JSTARS.2023.3251962  Published: 2023  
  Abstract:With the development of Earth observation technology, more multisource remote sensing images are obtained from various satellite sensors and significantly enrich the data source of change detection (CD). However, the utilization of multisource bitemporal images frequently introduces challenges during featuring or representing the various physical mechanisms of the observed landscapes and makes it more difficult to develop a general model for homogeneous and heterogeneous CD adaptively. In this article, we propose an adaptive spatial-spectral transformer CD network based on spectral token guidance, named STCD-Former. Specifically, a spectral transformer with dual-branch first encodes the diverse spectral sequence in spectral-wise to generate a corresponding spectral token. And then, the spectral token is used as guidance to interact with the patch token to learn the change rules. More significantly, to optimize the learning of difference information, we design a difference amplification module to highlight discriminative features by adaptively integrating the difference information into the feature embedding. Finally, the binary CD result is obtained by multilayer perceptron. The experimental results on three homogeneous datasets and one heterogeneous dataset have demonstrated that the proposed STCD-Former outperforms the other state-of-the-art methods qualitatively and visually. © 2008-2012 IEEE.
  Accession Number: 20231013688651
• Record 432 of
  
  Title:Snapshot dual-view 3D imaging
  
  Author(s):Ji, Chao(1,2); Fang, Mengyan(1,2); Xin, Liwei(1,3); He, Kai(1); Li, Yahui(1); Wang, Xing(1); Tian, Jinshou(1,4)
  Source: AIP Advances  Volume: 13  Issue: 4  Article Number: 045213  DOI: 10.1063/5.0142500  Published: April 1, 2023  
  Abstract:Multi-view 3D imaging is an indispensable imaging method for self-driving, 3D modeling, and other fields. However, there remains a scarcity of fast and efficient multi-view 3D imaging methods. In the present study, a snapshot dual-view 3D imaging setup based on the Coded Aperture Imaging method was introduced and experimentally demonstrated. The proposed method can simultaneously obtain 3D information from different views by means of a streak camera and two independent masks. Compared with traditional 3D imaging technology, our technique can meet the integrity and real-time requirements of 3D imaging while reducing the hardware cost of existing multi-view imaging methods. © 2023 Author(s).
  Accession Number: 20231713946298