2024
2024
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Record 73 of
Title:Spectral encoder to extract the efficient features of Raman spectra for reliable and precise quantitative analysis
Author Full Names:Gao, Chi(1,2,3); Fan, Qi(1,2); Zhao, Peng(1,2,3); Sun, Chao(1,2); Dang, Ruochen(1,2,3); Feng, Yutao(1); Hu, Bingliang(1,2); Wang, Quan(1,2)Source Title:Spectrochimica Acta - Part A: Molecular and Biomolecular SpectroscopyLanguage:EnglishDocument Type:Journal article (JA)Abstract:Raman spectroscopy has become a powerful analytical tool highly demanded in many applications such as microorganism sample analysis, food quality control, environmental science, and pharmaceutical analysis, owing to its non-invasiveness, simplicity, rapidity and ease of use. Among them, quantitative research using Raman spectroscopy is a crucial application field of spectral analysis. However, the entire process of quantitative modeling largely relies on the extraction of effective spectral features, particularly for measurements on complex samples or in environments with poor spectral signal quality. In this paper, we propose a method of utilizing a spectral encoder to extract effective spectral features, which can significantly enhance the reliability and precision of quantitative analysis. We built a latent encoded feature regression model; in the process of utilizing the autoencoder for reconstructing the spectrometer output, the latent feature obtained from the intermediate bottleneck layer is extracted. Then, these latent features are fed into a deep regression model for component concentration prediction. Through detailed ablation and comparative experiments, our proposed model demonstrates superior performance to common methods on single-component and multi-component mixture datasets, remarkably improving regression precision while without needing user-selected parameters and eliminating the interference of irrelevant and redundant information. Furthermore, in-depth analysis reveals that latent encoded feature possesses strong nonlinear feature representation capabilities, low computational costs, wide adaptability, and robustness against noise interference. This highlights its effectiveness in spectral regression tasks and indicates its potential in other application fields. Sufficient experimental results show that our proposed method provides a novel and effective feature extraction approach for spectral analysis, which is simple, suitable for various methods, and can meet the measurement needs of different real-world scenarios. ? 2024 Elsevier B.V.Affiliations:(1) Key Laboratory of Spectral Imaging Technology, Xi'an Institute of Optics and Precision Mechanics of the Chinese Academy of Sciences, Shaanxi; 710076, China; (2) The Key Laboratory of Biomedical Spectroscopy of Xi'an, Shaanxi; 710076, China; (3) University of Chinese Academy of Sciences, Beijing; 100049, ChinaPublication Year:2024Volume:312Article Number:124036DOI Link:10.1016/j.saa.2024.124036數(shù)據(jù)庫(kù)ID（收錄號(hào)）:20240815597901 -
Record 74 of
Title:Adaptive compound control of laser beam jitter in deep-space optical communication systems
Author Full Names:Yunhao, S.U.(1,2); Junfeng, H.A.N.(1); Wang, Xuan(1); Caiwen, M.A.(1); Jianming, W.U.(3)Source Title:Optics ExpressLanguage:EnglishDocument Type:Journal article (JA)Abstract:In deep-space optical communication systems, precise pointing and aiming of the laser beam is essential to ensure the stability of the laser link. In this paper, an adaptive compound control system based on adaptive feedforward and Proportional-Integral-Differentiation (PID) feedback is proposed. The feedforward controller is stabilized using Youla-Kucera (YK) parameterization. In the YK parameterized structure, the free parameter Q(z) consists of an adaptive filter. The proposed method constitutes an adaptive feedforward control algorithm through the adaptive filter Q(z). The problem of suppressing laser jitter is transformed into a problem of minimizing a sensitivity function containing the adaptive filter. The stability of the compound control system is ensured by configuring the individual parameters of the YK parameterized feedforward controller and the PID controller, and the adaptive regulation of the controller is realized on the premise of system stability. To verify the effectiveness of the compound control system, we established an experimental platform for laser beam stabilization control. We experimentally compare the effectiveness of the proposed control method with the classical method. The experimental results show that the method proposed in this paper can effectively suppress the complex laser beam jitter consisting of narrow-band sinusoidal and broad-band continuous vibrations. ? 2024 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreement.Affiliations:(1) Xi’an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi’an; 710119, China; (2) University of Chinese Academy of Sciences, Beijing; 100049, China; (3) Shanghai Academy of Spaceflight Technology, China Aerospace Science and Technology, Shanghai; 200240, ChinaPublication Year:2024Volume:32Issue:13Start Page:23228-23244DOI Link:10.1364/OE.521520數(shù)據(jù)庫(kù)ID（收錄號(hào)）:20242616351796 -
Record 75 of
Title:Design of Mantis-Shrimp-Inspired Multifunctional Imaging Sensors with Simultaneous Spectrum and Polarization Detection Capability at a Wide Waveband
Author Full Names:Wang, Tianxin(1,2); Wang, Shuai(1); Gao, Bo(1); Li, Chenxi(1); Yu, Weixing(1,2)Source Title:SensorsLanguage:EnglishDocument Type:Journal article (JA)Abstract:The remarkable light perception abilities of the mantis shrimp, which span a broad spectrum ranging from 300 nm to 720 nm and include the detection of polarized light, serve as the inspiration for our exploration. Drawing insights from the mantis shrimp’s unique visual system, we propose the design of a multifunctional imaging sensor capable of concurrently detecting spectrum and polarization across a wide waveband. This sensor is able to show spectral imaging capability through the utilization of a 16-channel multi-waveband Fabry–Pérot (FP) resonator filter array. The design incorporates a composite thin film structure comprising metal and dielectric layers as the reflector of the resonant cavity. The resulting metal–dielectric composite film FP resonator extends the operating bandwidth to cover both visible and infrared regions, specifically spanning a broader range from 450 nm to 900 nm. Furthermore, within this operational bandwidth, the metal–dielectric composite film FP resonator demonstrates an average peak transmittance exceeding 60%, representing a notable improvement over the metallic resonator. Additionally, aluminum-based metallic grating arrays are incorporated beneath the FP filter array to capture polarization information. This innovative approach enables the simultaneous acquisition of spectrum and polarization information using a single sensor device. The outcomes of this research hold promise for advancing the development of high-performance, multifunctional optical sensors, thereby unlocking new possibilities in the field of optical information acquisition. ? 2024 by the authors.Affiliations:(1) Key Laboratory of Spectral Imaging Technology, Xi’an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi’an; 710119, China; (2) Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing; 100049, ChinaPublication Year:2024Volume:24Issue:5Article Number:1689DOI Link:10.3390/s24051689數(shù)據(jù)庫(kù)ID（收錄號(hào)）:20241115750294 -
Record 76 of
Title:Research on satellite structural health monitoring based on ultrashort femtosecond grating array and artificial neural network
Author Full Names:Mu, Congying(1); Zhang, Yunshan(1,2); Li, Chuanxiang(3); Wang, Yunxin(1,2); Wang, Dayong(1,2); Hu, Shuyang(1); Fan, Li(4)Source Title:Optical Fiber TechnologyLanguage:EnglishDocument Type:Journal article (JA)Abstract:The safety of spacecraft and satellite in orbit is very important, and structural health monitoring is needed. At present, the existing technology is limited by load and difficult to realize. In this paper, we propose a feasible method to detect and locate the damage of satellite by combining ultrashort femtosecond grating array inscribed on oxide-doped fiber with multilayer artificial neural network. An oxide-doped fiber with high robustness is designed, and ultrashort grating arrays are fabricated on the fiber by femtosecond laser point-by-point writing technology. The effects of impactor velocity and angle on impact response was investigated by numerical simulations and physical experiments. Subsequently, repeated impact experiments were conducted on the satellite to obtain the training dataset and testing dataset for two-dimensional convolutional neural network. The network with symmetric convention kernels has an 88.12% localization accuracy and a better performance in boundary region, and the network architecture with asymmetric convention kernels has a 90.31% accuracy and a better performance in middle region. ? 2024 Elsevier Inc.Affiliations:(1) School of Physics and Optoelectronic Engineering, Beijing University of Technology, Beijing; 100124, China; (2) Engineering Research Center of Precision Measurement Technology and Instruments, Beijing; 100124, China; (3) High-Tech Institution of Xi'an, Xi'an; 710025, China; (4) Huzhou Institute of Zhejiang University, Huzhou; 313000, ChinaPublication Year:2024Volume:88Article Number:103981DOI Link:10.1016/j.yofte.2024.103981數(shù)據(jù)庫(kù)ID（收錄號(hào)）:20243917099569 -
Record 77 of
Title:Efficient dense attention fusion network with channel correlation loss for road damage detection
Author Full Names:Liu, Zihan(1); Jing, Kaifeng(1); Yang, Kai(2,3); Zhang, ZhiJun(2); Li, Xijie(2,3,4)Source Title:IET Intelligent Transport SystemsLanguage:EnglishDocument Type:Journal article (JA)Abstract:Road?damage detection (RDD) is critical to society's safety and the efficient allocation of resources. Most road damage detection methods which directly adopt various object detection models face some significant challenges due to the characteristics of the RDD task. First, the damaged objects in the road images are highly diverse in scales and difficult to differentiate, making it more challenging than other tasks. Second, existing methods neglect the relationship between the feature distribution and model structure, which makes it difficult for optimization. To address these challenges, this study proposes an efficient dense attention fusion network with channel correlation loss for road damage detection. First, the K-Means++ algorithm is applied for data preprocessing to optimize the initial cluster centers and improve the model detection accuracy. Second, a dense attention fusion module is proposed to learn spatial-spectral attention to enhance multi-scale fusion features and improve the ability of the model to detect damage areas at different scales. Third, the channel correlation loss is adopted in the class prediction process to maintain the separability of intra and inter-class. The experimental results on the collected RDDA dataset and RDD2022 dataset show that the proposed method achieves state-of-the-art performance. ? 2023 The Author(s). IET Intelligent Transport Systems published by John Wiley & Sons Ltd on behalf of The Institution of Engineering and Technology.Affiliations:(1) AmazingX Academy, FoShan, China; (2) Wuhan University of Technology, School of Computer Science and Artificial Intelligence, Wuhan, China; (3) Sanya Science and Education Innovation Park of Wuhan University of Technology, Sanya, China; (4) Xi'an Institute of Optics and Precision Mechanics of CAS, Xi'an, ChinaPublication Year:2024Volume:18Issue:10Start Page:1747-1759DOI Link:10.1049/itr2.12369數(shù)據(jù)庫(kù)ID（收錄號(hào)）:20231714009506 -
Record 78 of
Title:Measurement of deep hole verticality by monocular vision
Author Full Names:Zhu, Hui(1); Li, Hua(1); Liu, Wei(1); Li, Zhaohui(1); Tan, Wenlong(2)Source Title:Proceedings of SPIE - The International Society for Optical EngineeringLanguage:EnglishDocument Type:Conference article (CA)Conference Title:2024 International Conference on Optoelectronic Information and Optical Engineering, OIOE 2024Conference Date:March 8, 2024 - March 10, 2024Conference Location:Kunming, ChinaConference Sponsor:Academic Exchange Information Centre (AEIC)Abstract:To propose a measurement method for the verticality of deep hole based on monocular vision. The coordinate conversion matrix of pentaprism circumferential scanning is derived, and the circumferential scanning trajectory and characteristics of the targets are simulated and analyzed. Based on the visual axis, the normal direction of the measurement datum is constructed to accurately compensate the error between the camera visual axis and the tube datum. For the simulated tube with a radius of 956.21mm, a thickness of 999.55mm and a verticality of 0 mm, the verticality accuracy measured by the system can reach 0.03mm. The actual test shows that the method of measuring the verticality of deep hole with monocular vision is effective and feasible. The system is easy to operate and highly automated, which can greatly improve the measurement efficiency and ensure the measurement accuracy. It is of great significance to the production and measurement of deep holes in nuclear tube sheet. ? 2024 SPIE.Affiliations:(1) Xi’an Institute of Optics and Precision Mechanics of CAS, No.17, New Industrial Park, Xi’an High-tech Zone, Xi’an; 710119, China; (2) Shanghai Electric Nuclear Power Equipment Corporation Ltd., 77 Yalin Road, Pudong New Area, Shanghai; 201306, ChinaPublication Year:2024Volume:13182Article Number:131820BDOI Link:10.1117/12.3030360數(shù)據(jù)庫(kù)ID（收錄號(hào)）:20242516298474 -
Record 79 of
Title:Polarization Effects in Photoionization of Excited Hydrogen Atom
Author Full Names:Zhong, Mingchen(1); Wan, Wenqin(1); Pi, Liangwen(2); Jiang, Weichao(1)Source Title:Guangxue Xuebao/Acta Optica SinicaLanguage:ChineseDocument Type:Journal article (JA)Abstract:Objective The interaction between strong laser fields and matter has emerged as a prominent tool for probing the internal structure of atoms and molecules and field-induced ultrafast electron dynamics. During the multiphoton ionization of atoms and molecules by intense laser pulses, ionized electron wave packets from different paths interfere, resulting in complex interference patterns in the photoelectron momentum distributions (PMDs). Over the past decades, a prominent interference structure known as strong-field photoelectron holography (SFPH) has been observed. In molecule fields, researchers use holographic structures to probe molecular structure and orientation dynamics information, but no relevant literature has been found in the atomic field. By numerically simulating the interaction between the excited state 2pz of a hydrogen atom and linearly polarized laser pulses with different polarization directions, we can extract the structural information of atomic orbitals from the PMDs. In addition, we also discuss a feasible pump-probe scheme for experimental validation. Methods To simulate atomic ionization in a linearly polarized laser field, we numerically solve the three-dimensional time-dependent Schr?dinger equation (TDSE) in the velocity gauge with dipole approximation. We use the finite-element discrete variable representation (FE-DVR) method to discretize the radial part of the wave function. For the time evolution of the wave function, we use the split-Lanczos method. After the laser pulse concludes, the ionization probability is extracted from the final wave function by projecting it onto the scattering state. Results and Discussions The configuration of the present laser-atom interaction is illustrated in Fig. 1. The quantization axis of the state 2pz is along the z-axis. Two polarization directions of the laser pulse, Θ = 0 [Fig. 1(a)] and π/6 [Fig. 1(b)], are presented. The wavelength, pulse duration, and peak intensity of the laser pulse are fixed to be 2000 nm, 10 optical cycles, and 1013 W/cm2, respectively. The PMDs at different angles Θ are given in Fig. 2. Different angles indeed give rise to different PMDs. We can observe the PMDs are symmetrical with respect to the laser polarization at Θ = 0 and π/2 [Figs. 2(a) and 2(d)], while such symmetry is broken at Θ = π/6 and π/3 [Figs. 2(b) and 2(c)]. In the tunneling ionization regime, the symmetry of the distribution of the initial transverse momentum of electrons depends on the Fourier transform of the initial wave function. Based on adiabatic approximation theory, we found that the symmetry of both holographic and fan-shaped interference structures closely depends on the initial transverse momentum distribution of the direct electrons. Next, we investigate how tunneling filters with spherically symmetric and non-spherically symmetric orbits affect the initial transverse momentum distribution of electrons (Fig. 3). For the 2pz orbital, the transverse momentum k|ψ2p is symmetric only when k? = 0 and is asymmetric for other values [Fig. 3(d)]. Clearly, the asymmetrical PMDs exactly mimic the asymmetrical momentum distribution of the initial orbital. To quantitatively study the correlation between the initial orbital and the PMDs, we define a parameter ΔY to describe the asymmetry. The research found that the asymmetry of the initial orbital, denoted as ΔY2p, qualitatively describes the changing trend of the ionized electron distribution ΔY with Θ increasing (Fig. 4). Therefore, the asymmetry parameter of the final electron reflects the information of atomic orbital structure. We extend our discussion to the multi-photon ionization and transition ionization regime in Fig. 5(a), the asymmetry parameter ΔY2p still well reproduces the Θ-dependence of the photoelectron asymmetry ΔY after extending the ionization from the tunneling to the multi-photon and transition regime. Therefore, we can generally conclude that the asymmetry in photoelectron distribution correlates with the asymmetry of the initial-state momentum distribution. We show the dependence of the asymmetry parameter ?Y on the Keldysh parameter γ at a specific angle Θ = π/4 in Fig. 5(b). In the tunneling regime γ 1. This is because in the transition and multiphoton ionization regions, there are multiple resonant ionization channels, making it difficult to maintain consistency between the PMDs and the initial transverse momentum distribution. Experimental verification of the present theoretical predictions requires a pump-probe scheme, as the excited state 2pz is not naturally largely populated. We should use a pump laser pulse to prepare the excited state 2pz before it interacts with the probe pulse. The configuration of the pump and probe laser pulses is illustrated in Fig. 6(a). The PMDs in the pump-probe scheme are shown in Fig. 6(b). We observe that the result is highly consistent with that in Fig. 2(c). To better understand the potential impact of the pump-probe method on extracting ionization electron asymmetry, we further investigated the influence of pump duration and the time delay between the two laser pulses on the extraction of asymmetry parameters in Figs. 6(c) and 6(d). We present a theoretical approach to probe atomic orbital structure information and investigate the correlation between atomic orbits and final state momentum distributions under different ionization mechanisms. Finally, we consider implementing feasible pump-probe detection schemes to validate its predictions. Conclusions We have theoretically investigated the photoionization of the excited state 2pz of hydrogen atoms by linearly polarized laser pulses. We identified asymmetrical PMDs with respect to the laser polarization direction. In the tunneling ionization regime, this asymmetry arises from the asymmetrical distribution of the initial orbital with respect to the polarization direction, resulting in an unequal transverse momentum distribution of the initial electrons. In both tunneling and multi-photon ionization regimes, the asymmetry parameter ?Y of the PMDs as a function of the laser polarization direction Θ is qualitatively reproduced by the asymmetry parameter ΔY2p of the initial orbital. Our theoretical prediction could be experimentally verified in a pump-probe scheme. Our calculation indicates that the asymmetry parameter ?Y of the PMDs can be well extracted even if the population of the excited state 2pz after the pump pulse ends is not large. ? 2024 Chinese Optical Society. All rights reserved.Affiliations:(1) Institute of Quantum Precision Measurement, College of Physics, Optoelectronic Engineering, Shenzhen University, Guangdong, Shenzhen; 518060, China; (2) Center for Attosecond Science and Technology, Xi’an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Shaanxi, Xi’an; 710119, ChinaPublication Year:2024Volume:44Issue:16Article Number:1602002DOI Link:10.3788/AOS240723數(shù)據(jù)庫(kù)ID（收錄號(hào)）:20243216838147 -
Record 80 of
Title:Optical-signal token guided change detection network for heterogeneous remote sensing image
Author Full Names:Liu, Qinsen(1); Sun, Bangyong(1,2)Source Title:National Remote Sensing BulletinLanguage:ChineseDocument Type:Journal article (JA)Abstract:Change Detection (CD) is a vital technique for identifying and analyzing changes over time in a specific area using optical signals from remote sensing images. This technique has been extensively utilized in various fields, including national defense security, environmental monitoring, and urban construction. However, some challenges in achieving accurate and reliable CD are still encountered due to inherent disparities in imaging mechanisms, spectral ranges, and spatial resolutions among heterogeneous images. These challenges lead to issues such as inadequate accuracy, missed detections, and false detections. Heterogeneous remote sensing images can be regarded as sequences of different optical signals from the channel perspective. For example, RGB and infrared images can be regarded as sequences of spectral signals from different ranges. Transformers employ a multi-head attention mechanism that can effectively handle and analyze sequence information to achieve accurate heterogeneous CD. Thus, the paper proposes an optical signal token guided CD network for heterogeneous remote sensing images. This paper presents a novel heterogeneous CD network, primarily comprising the optical-signal token transformer (OT-Former) and the cross-temporal transformer (CT-Former). The proposed method demonstrates the capacity to effectively handle diverse remote sensing images of distinct categories and attain precise CD results. Specifically, OT-Former can encode diverse heterogeneous images in channel-wise for adaptively generating the optical-signal tokens. Meanwhile, CT-Former can use the optical-signal tokens as a guide to interact with the patch token for the learning of change rules. Moreover, a Difference Amplification Module (DAM) is embedded into the network to enhance the extraction of difference information. This module utilizes a 1×2 convolutional kernel to effectively fuse difference information. Finally, the differential token is predicted by multilayer perceptron to output the CD results. Experiments were conducted on three heterogeneous datasets and one homogeneous dataset to evaluate the performance of the proposed method. Furthermore, the proposed method was compared with six typical CD methods and evaluated the performance using overall accuracy (OA), Kappa coefficient, and F1-score, among other evaluation metrics, to validate the effectiveness of the proposed network in this study. A limited number of samples were utilized for training during the experiment. Under identical experimental conditions, the proposed method demonstrated exceptional performance in homogeneous and heterogeneous CD. The results show that the proposed approach surpasses existing state-of-the-art methods in terms of qualitative and visual performance. Additionally, ablation experiments and parameter analyses were conducted to validate the effectiveness of the proposed methods, including the OT-Former, CT-Former, and DAM modules, and to assess the impact of various parameters within the network. Overall, the current study presents a novel heterogeneous CD network based on the transformer framework. Within this network, OT-Former is proposed to achieve the adaptive generation of optical-signal tokens from diverse remote sensing images. Moreover, the CT-Former utilizes these optical-signal tokens as a guide to facilitate interaction with patch tokens for the learning of change rules. Additionally, DAM modules were embedded into the network to effectively extract the difference information. An extremely limited number of samples were utilized only for training in the experiments. Remarkably, the proposed method outperformed the existing state-of-the-art methods, achieving a significantly advanced performance in heterogeneous CD. ? 2024 Science Press. All rights reserved.Affiliations:(1) Faculty of Printing, Packaging Engineering and Digital Media Technology, Xi’an University of Technology, Xi’an; 710054, China; (2) State Key Laboratory of Transient Optics and Photonics, Xi’an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi’an; 710119, ChinaPublication Year:2024Volume:28Issue:1Start Page:87-104DOI Link:10.11834/jrs.20233067數(shù)據(jù)庫(kù)ID（收錄號(hào)）:20241515892473 -
Record 81 of
Title:Semantic-Guided Polarization Spectral Image Fusion Method for Camouflage Target Detection
Author Full Names:Sun, Bangyong(1,2); Shi, Yuhan(1); Yu, Tao(2)Source Title:Guangxue Xuebao/Acta Optica SinicaLanguage:ChineseDocument Type:Journal article (JA)Abstract:Objective Camouflage detection aims to distinguish and separate the characteristics of camouflage targets and natural backgrounds from battlefield images, determining the category attributes and coordinate information of the targets. Conventional optical detection struggles with distinguishing"same color and different spectrum"or"foreign object and same spectrum"properties between camouflage targets and backgrounds. As a result, existing camouflage detection primarily relies on spectral imaging or polarization imaging technology. Recently, scholars have combined the advantages of these technologies to develop polarization spectral cameras, which simultaneously capture spectral and polarization information. Image fusion technology further enhances target visibility and contrast between artificial targets and natural backgrounds. Therefore, studying image fusion technology for multimodal data is crucial for improving the accuracy of camouflage target detection under multi-sensor imaging conditions. Methods We propose a polarization spectral image fusion method to achieve accurate detection of camouflage targets using the generated fusion images. The process includes four main parts. Firstly, using our team-developed polarization spectral camera, we image backgrounds containing camouflage targets to obtain spectral cubes with four different polarization states. Secondly, we preprocess the polarized spectral images to make them suitable for network input, including spectral reconstruction, polarized image registration, and image denoising. We select single-band images suitable for detection by analyzing the comparative characteristics of camouflage targets and backgrounds in the four polarized spectral cubes. Then, we fuse the four polarized images using PE-Net to enhance polarization semantic information, improving our fusion strategy, and output high contrast fused images of the camouflage targets and backgrounds. Finally, we use the Otsu binary segmentation algorithm to detect camouflage targets and obtain their binary position information. Results and Discussions The proposed polarization spectrum fusion method, Po-NSCT, performs better on four non-reference indicators compared to seven comparison methods (Fig. 9). Compared with NSCT, it increases information entropy (EN) by 0.0656, average gradient (AG) by 2.0912, standard deviation (SD) by 2.3816, and spatial frequency (SF) by 5.8511. Although it decreases in QAB/F compared to NSCT, introducing Stokes vector Q for semantic guidance improves non-reference indicators for better camouflage target detection. For advanced camouflage target detection tasks, Otsu binary segmentation is performed. The Po-NSCT fusion method fully recognizes 12 types of camouflage targets, including nets, suits, and helmets. Compared with the seven comparison methods, the proposed method significantly improves the intersection to IoU, accuracy, and F1 score, with an IoU increase of 0.1543, accuracy increase of 0.1778, and F1 score increase of 0.1068 compared to the original polarized spectral image (Fig. 13). The experimental results show that our proposed fusion method enhances camouflage detection accuracy and reduces the background misjudgment. The polarization semantic guidance module and improved fusion strategy achieve optimal indicators, enriching image information, improving image contrast, and enhancing image texture details. Polarization spectral imaging leverages multiple sensor advantages to enhance image detection performance. Conclusions This paper proposes a polarization spectrum image fusion method named Po-NSCT, which utilizes non-downsampling contour wave transformation for recognizing and detecting camouflage targets. The study comprises three main parts. Firstly, we propose the Po-NSCT fusion method to enhance image fusion performance for polarization spectral images. Secondly, we introduce a polarization semantic guidance module to suppress redundant information in polarization spectral images. Finally, we improve target detection accuracy by preprocessing high and low-frequency images before fusion, leveraging the specificity of polarization information. Polarization spectral imaging technology integrates imaging, spectral, and polarization technologies to enhance target recognition in complex environments. Applying this technology for image fusion tasks filters image information and retains more useful information. By fusing spectral and polarization images, effective complementarity of advantageous information from different modalities is achieved, compensating for single sensor limitations and showcasing unique advantages. This method provides a novel image processing approach for polarization spectral imaging systems and holds significant development potential. ? 2024 Chinese Optical Society. All rights reserved.Affiliations:(1) Faculty of Printing, Packaging Engineering and Digital Media Technology, Xi’an University of Technology, Shaanxi, Xi’an; 710054, China; (2) Key Laboratory of Spectral Imaging Technology, Xi’an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Shaanxi, Xi’an; 710119, ChinaPublication Year:2024Volume:44Issue:19Article Number:1910001DOI Link:10.3788/AOS240726數(shù)據(jù)庫(kù)ID（收錄號(hào)）:20244317255220 -
Record 82 of
Title:Optimization of Thin-Disk Laser Pump Scheme for Enhanced Efficiency
Author Full Names:Lei, Bingying(1); Zhang, Liyi(1,2); Cheng, Yanshen(1,2); Yao, Shuai(1); Wang, Le(1); Wang, Yishan(1,2); Lin, Hua(1); Fu, Yuxi(1)Source Title:Proceedings of SPIE - The International Society for Optical EngineeringLanguage:EnglishDocument Type:Conference article (CA)Conference Title:2024 Applied Optics and Photonics China: Laser Technology and Applications, AOPC 2024Conference Date:July 23, 2024 - July 26, 2024Conference Location:Beijing, ChinaConference Sponsor:Chinese Society for Optical Engineering (CSOE)Abstract:We introduce novel pump layouts for thin-disk lasers that maximize the number of passes while maintaining a fixed pump module size and moderate pump source quality. These advanced layouts are based on a nested multi-pass optical system, achieved by adding a series of deflecting prism pairs to ensure a uniform and compact beam distribution. This innovative approach not only increases the number of pump passes but also significantly enhances the overall efficiency of the laser system. As a result, it becomes feasible to use active materials with lower absorption rates, which are typically challenging to employ in standard designs. The main advantage of our method lies in its ability to minimize the typical increases in overall size and the stringent pump source quality requirements that are often associated with conventional multi-pass pump designs. By optimizing the optical arrangement, we ensure that the enhanced performance does not come at the expense of increased system complexity or footprint. This makes our design particularly suitable for industrial applications where space, cost, and reliability are critical factors. Furthermore, the use of commercially available pump optics, combined with the additional deflecting prism pairs, provides a practical and scalable solution that can be readily implemented. Our novel pump layouts thus offer a significant advancement in thin-disk laser technology, paving the way for more efficient and compact laser systems that can meet the demands of various industrial applications. ? 2024 SPIE.Affiliations:(1) Center for Attosecond Science and Technology, State Key Laboratory of Transient Optics and Photonics, Xi’an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi’an; 710119, China; (2) University of Chinese Academy of Sciences, Beijing; 100049, ChinaPublication Year:2024Volume:13492Article Number:1349204DOI Link:10.1117/12.3045716數(shù)據(jù)庫(kù)ID（收錄號(hào)）:20250117638867 -
Record 83 of
Title:Evaluation of Point-source Microscope Localization Accuracy based on Measurement system analysis methods
Author Full Names:Fu, Xihong(1,2); Zuo, Zhiwei(3); Lin, Xuezhu(3,4); Yang, Yetao(1); Yang, Fan(1); Li, Hua(1,2); Li, Zhiguo(1,2); Kang, Shifa(1,2)Source Title:Proceedings of SPIE - The International Society for Optical EngineeringLanguage:EnglishDocument Type:Conference article (CA)Conference Title:2024 Conference on Spectral Technology and Applications, CSTA 2024Conference Date:May 9, 2024 - May 11, 2024Conference Location:Dalian, ChinaConference Sponsor:Chinese Society for Optical EngineeringAbstract:Spherical and aspherical reflective optical systems are widely used in modern optical systems such as astronomical instruments and space optics due to their advantages of large field of view, absence of chromatic aberration, excellent image quality, and compact structure. However, during the assembly and adjustment process, the key is to quickly and accurately locate the curvature centers of multiple surfaces in the reflective system. Traditional methods rely on laser interferometers to monitor the entire system, which is not only cumbersome and time-consuming but also difficult to apply to the rapid adjustment of complex multi-mirror optical systems, and the required equipment is expensive. The Point Source Microscope (PSM) is a new type of alignment instrument that, based on the principle of spherical autocollimation, can quickly locate the curvature center positions of optical elements. Its simple structure and low cost make it an essential monitoring and measurement device during the assembly of complex off-axis optical systems. However, in practical applications, it has been found that the positioning accuracy of the curvature center of optical elements monitored by the PSM is influenced by many factors, with issues such as multi-degree-of-freedom compensation and sensitivity. Therefore, this paper proposes to use Measurement System Analysis (MSA) to further evaluate and analyze the positioning accuracy of the PSM to improve its accuracy. ? 2024 SPIE.Affiliations:(1) Xi'an Institute of Optics and Precision Mechanics of CAS, Xi'an, China; (2) University of Chinese Academy of Sciences, Beijing, China; (3) School of Optoelectronic Engineering, Changchun University of Science and Technology, Changchun, China; (4) Zhongshan Institute of Changchun University of Science and Technology, Zhongshan, ChinaPublication Year:2024Volume:13283Article Number:132833LDOI Link:10.1117/12.3037137數(shù)據(jù)庫(kù)ID（收錄號(hào)）:20245217584302 -
Record 84 of
Title:Remote Sensing Image Dehazing via Dual-View Knowledge Transfer
Author Full Names:Yang, Lei(1,2); Cao, Jianzhong(1,2); Bian, He(1,2); Qu, Rui(1); Guo, Huinan(1); Ning, Hailong(3)Source Title:Applied Sciences (Switzerland)Language:EnglishDocument Type:Journal article (JA)Abstract:Remote-sensing image dehazing (RSID) is crucial for applications such as military surveillance and disaster assessment. However, current methods often rely on complex network architectures, compromising computational efficiency and scalability. Furthermore, the scarcity of annotated remote-sensing-dehazing datasets hinders model development. To address these issues, a Dual-View Knowledge Transfer (DVKT) framework is proposed to generate a lightweight and efficient student network by distilling knowledge from a pre-trained teacher network on natural image dehazing datasets. The DVKT framework includes two novel knowledge-transfer modules: Intra-layer Transfer (Intra-KT) and Inter-layer Knowledge Transfer (Inter-KT) modules. Specifically, the Intra-KT module is designed to correct the learning bias of the student network by distilling and transferring knowledge from a well-trained teacher network. The Inter-KT module is devised to distill and transfer knowledge about cross-layer correlations. This enables the student network to learn hierarchical and cross-layer dehazing knowledge from the teacher network, thereby extracting compact and effective features. Evaluation results on benchmark datasets demonstrate that the proposed DVKT framework achieves superior performance for RSID. In particular, the distilled model achieves a significant speedup with less than 6% of the parameters and computational cost of the original model, while maintaining a state-of-the-art dehazing performance. ? 2024 by the authors.Affiliations:(1) Xi’an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi’an; 710119, China; (2) University of Chinese Academy of Sciences, Beijing; 100049, China; (3) School of Computer Science and Technology, Xi’an University of Posts and Telecommunications, Xi’an; 710121, ChinaPublication Year:2024Volume:14Issue:19Article Number:8633DOI Link:10.3390/app14198633數(shù)據(jù)庫(kù)ID（收錄號(hào)）:20244317228501