OPT OpenIR中国科学院西安光学精密机械研究所http://ir.opt.ac.cn:802024-03-19T05:37:45Z2024-03-19T05:37:45ZFatigue mechanism analysis and life prediction model of piezoelectric ceramic tube based on fiber-optic nutatorPeng, Bohttp://ir.opt.ac.cn:80/handle/181661/972182024-03-19T02:12:45Z2024-03-19T02:12:45Z题名: Fatigue mechanism analysis and life prediction model of piezoelectric ceramic tube based on fiber-optic nutator
作者: Peng, Bo2024-03-19T02:12:45ZResearch on the Effect of Vibrational Micro-Displacement of an Astronomical Camera on Detector ImagingLiu, BinGuan, ShouxinWang, FeichengZhang, XiaomingYu, TaoWei, Ruyihttp://ir.opt.ac.cn:80/handle/181661/972172024-03-19T01:55:04Z2024-03-15T09:08:50Z题名: Research on the Effect of Vibrational Micro-Displacement of an Astronomical Camera on Detector Imaging
作者: Liu, Bin; Guan, Shouxin; Wang, Feicheng; Zhang, Xiaoming; Yu, Tao; Wei, Ruyi
摘要: <p>Scientific-grade cameras are frequently employed in industries such as spectral imaging technology, aircraft, medical detection, and astronomy, and are characterized by high precision, high quality, fast speed, and high sensitivity. Especially in the field of astronomy, obtaining information about faint light often requires long exposure with high-resolution cameras, which means that any external factors can cause the camera to become unstable and result in increased errors in the detection results. This paper aims to investigate the effect of displacement introduced by various vibration factors on the imaging of an astronomical camera during long exposure. The sources of vibration are divided into external vibration and internal vibration. External vibration mainly includes environmental vibration and resonance effects, while internal vibration mainly refers to the vibration caused by the force generated by the refrigeration module inside the camera during the working process of the camera. The cooling module is divided into water-cooled and air-cooled modes. Through the displacement and vibration experiments conducted on the camera, it is proven that the air-cooled mode will cause the camera to produce greater displacement changes relative to the water-cooled mode, leading to blurring of the imaging results and lowering the accuracy of astronomical detection. This paper compares the effects of displacement produced by two methods, fan cooling and water-circulation cooling, and proposes improvements to minimize the displacement variations in the camera and improve the imaging quality. This study provides a reference basis for the design of astronomical detection instruments and for determining the vibration source of cameras, which helps to promote the further development of astronomical detection.</p>2024-03-15T09:08:50ZComplex Noise-Based Phase Retrieval Using Total Variation and Wavelet Transform RegularizationQin, XingGao, XinYang, XiaoxuXie, Meilinhttp://ir.opt.ac.cn:80/handle/181661/972162024-03-18T02:26:02Z2024-03-15T09:08:48Z题名: Complex Noise-Based Phase Retrieval Using Total Variation and Wavelet Transform Regularization
作者: Qin, Xing; Gao, Xin; Yang, Xiaoxu; Xie, Meilin
摘要: <p>This paper presents a phase retrieval algorithm that incorporates sparsity priors into total variation and framelet regularization. The proposed algorithm exploits the sparsity priors in both the gradient domain and the spatial distribution domain to impose desirable characteristics on the reconstructed image. We utilize structured illuminated patterns in holography, consisting of three light fields. The theoretical and numerical analyses demonstrate that when the illumination pattern parameters are non-integers, the three diffracted data sets are sufficient for image restoration. The proposed model is solved using the alternating direction multiplier method. The numerical experiments confirm the theoretical findings of the lighting mode settings, and the algorithm effectively recovers the object from Gaussian and salt-pepper noise.</p>2024-03-15T09:08:48ZMethodology and Modeling of UAV Push-Broom Hyperspectral BRDF Observation Considering Illumination CorrectionWang, ZhuoLi, HaiweiWang, ShuangSong, LiyaoChen, Junyuhttp://ir.opt.ac.cn:80/handle/181661/972152024-03-19T01:56:19Z2024-03-15T09:08:46Z题名: Methodology and Modeling of UAV Push-Broom Hyperspectral BRDF Observation Considering Illumination Correction
作者: Wang, Zhuo; Li, Haiwei; Wang, Shuang; Song, Liyao; Chen, Junyu
摘要: <p>The Bidirectional Reflectance Distribution Function (BRDF) is a critical spatial distribution parameter in the quantitative research of remote sensing and has a wide range of applications in radiometric correction, elemental inversion, and surface feature estimation. As a new means of BRDF modeling, UAV push-broom hyperspectral imaging is limited by the push-broom imaging method, and the multi-angle information is often difficult to obtain. In addition, the random variation of solar illumination during UAV low-altitude flight makes the irradiance between different push-broom hyperspectral rows and different airstrips inconsistent, which significantly affects the radiometric consistency of BRDF modeling and results in the difficulty of accurately portraying the three-dimensional spatial reflectance distribution in the UAV model. These problems largely impede the application of outdoor BRDF. Based on this, this paper proposes a fast multi-angle information acquisition scheme with a high-accuracy BRDF modeling method considering illumination variations, which mainly involves a lightweight system for BRDF acquisition and three improved BRDF models considering illumination corrections. We adopt multi-rectangular nested flight paths for multi-gray level targets, use multi-mode equipment to acquire spatial illumination changes and multi-angle reflectivity information in real-time, and introduce the illumination correction factor K through data coupling to improve the kernel, Hapke, and RPV models, and, overall, the accuracy of the improved model is increased by 20.83%, 11.11%, and 31.48%, respectively. The results show that our proposed method can acquire multi-angle information quickly and accurately using push-broom hyperspectral imaging, and the improved model eliminates the negative effect of illumination on BRDF modeling. This work is vital for expanding the multi-angle information acquisition pathway and high-efficiency and high-precision outdoor BRDF modeling.</p>2024-03-15T09:08:46ZEffective correction of dissolved organic carbon interference in nitrate detection using ultraviolet spectroscopy combined with the equivalent concentration offset methodDong, JingTang, JunwuWu, GuojunXin, YuLi, RuizhuoLi, Yahuihttp://ir.opt.ac.cn:80/handle/181661/972142024-03-18T02:30:07Z2024-03-15T09:08:44Z题名: Effective correction of dissolved organic carbon interference in nitrate detection using ultraviolet spectroscopy combined with the equivalent concentration offset method
作者: Dong, Jing; Tang, Junwu; Wu, Guojun; Xin, Yu; Li, Ruizhuo; Li, Yahui
摘要: <p>Nitrate contamination in water sources poses a substantial environmental and health risk. However, accurate detection of nitrate in water, particularly in the presence of dissolved organic carbon (DOC) interference, remains a significant analytical challenge. This study investigates a novel approach for the reliable detection of nitrate in water samples with varying levels of DOC interference based on the equivalent concentration offset method. The characteristic wavelengths of DOC were determined based on the first-order derivatives, and a nitrate concentration prediction model based on partial least squares (PLS) was established using the absorption spectra of nitrate solutions. Subsequently, the absorption spectra of the nitrate solutions were subtracted from that of the nitrate-DOC mixed solutions to obtain the difference spectra. These difference spectra were introduced into the nitrate prediction model to calculate the equivalent concentration offset values caused by DOC. Finally, a DOC interference correction model was established based on a binary linear regression between the absorbances at the DOC characteristic wavelengths and the DOC-induced equivalent concentration offset values of nitrate. Additionally, a modeling wavelength selection algorithm based on a sliding window was proposed to ensure the accuracy of the nitrate concentration prediction model and the equivalent concentration offset model. The experimental results demonstrated that by correcting the DOC-induced offsets, the relative error of nitrate prediction was reduced from 94.44% to 3.36%, and the root mean square error of prediction was reduced from 1.6108 mg L-1 to 0.1037 mg L-1, which is a significant correction effect. The proposed method applied to predict nitrate concentrations in samples from two different water sources shows a certain degree of comparability with the standard method. It proves that this method can effectively correct the deviations in nitrate measurements caused by DOC and improve the accuracy of nitrate measurement. A simple and rapid method for DOC interference correction based on an equivalent concentration offset method was proposed to address the challenging issue of DOC interference in nitrate detection in aquatic environments.</p>2024-03-15T09:08:44ZA Snapshot Multi-Spectral Demosaicing Method for Multi-Spectral Filter Array Images Based on Channel Attention NetworkZhang, XuejunDai, YidanZhang, GengZhang, XueminHu, Binglianghttp://ir.opt.ac.cn:80/handle/181661/972132024-03-18T02:31:50Z2024-03-15T09:08:42Z题名: A Snapshot Multi-Spectral Demosaicing Method for Multi-Spectral Filter Array Images Based on Channel Attention Network
作者: Zhang, Xuejun; Dai, Yidan; Zhang, Geng; Zhang, Xuemin; Hu, Bingliang
摘要: <p>Multi-spectral imaging technologies have made great progress in the past few decades. The development of snapshot cameras equipped with a specific multi-spectral filter array (MSFA) allow dynamic scenes to be captured on a miniaturized platform across multiple spectral bands, opening up extensive applications in quantitative and visualized analysis. However, a snapshot camera based on MSFA captures a single band per pixel; thus, the other spectral band components of pixels are all missed. The raw images, which are captured by snapshot multi-spectral imaging systems, require a reconstruction procedure called demosaicing to estimate a fully defined multi-spectral image (MSI). With increasing spectral bands, the challenge of demosaicing becomes more difficult. Furthermore, the existing demosaicing methods will produce adverse artifacts and aliasing because of the adverse effects of spatial interpolation and the inadequacy of the number of layers in the network structure. In this paper, a novel multi-spectral demosaicing method based on a deep convolution neural network (CNN) is proposed for the reconstruction of full-resolution multi-spectral images from raw MSFA-based spectral mosaic images. The CNN is integrated with the channel attention mechanism to protect important channel features. We verify the merits of the proposed method using 5 x 5 raw mosaic images on synthetic as well as real-world data. The experimental results show that the proposed method outperforms the existing demosaicing methods in terms of spatial details and spectral fidelity.</p>2024-03-15T09:08:42ZDesign of Optical System for Ultra-Large Range Line-Sweep Spectral Confocal Displacement SensorYang, WeiguangDu, JianQi, MeijieYan, JiayueCheng, MohanZhang, Zhoufenghttp://ir.opt.ac.cn:80/handle/181661/972122024-03-19T01:52:18Z2024-03-15T09:08:40Z题名: Design of Optical System for Ultra-Large Range Line-Sweep Spectral Confocal Displacement Sensor
作者: Yang, Weiguang; Du, Jian; Qi, Meijie; Yan, Jiayue; Cheng, Mohan; Zhang, Zhoufeng
摘要: <p>The spectrum confocal displacement sensor is an innovative type of photoelectric sensor. The non-contact advantages of this method include the capacity to obtain highly accurate measurements without inflicting any harm as well as the ability to determine the object's surface contour recovery by reconstructing the measurement data. Consequently, it has been widely used in the field of three-dimensional topographic measuring. The spectral confocal displacement sensor consists of a light source, a dispersive objective, and an imaging spectrometer. The scanning mode can be categorized into point scanning and line scanning. Point scanning is inherently present when the scanning efficiency is low, resulting in a slower measurement speed. Further improvements are necessary in the research on the line-scanning type. It is crucial to expand the measurement range of existing studies to overcome the limitations encountered during the detection process. The objective of this study is to overcome the constraints of the existing line-swept spectral confocal displacement sensor's limited measuring range and lack of theoretical foundation for the entire system. This is accomplished by suggesting an appropriate approach for creating the optical design of the dispersive objective lens in the line-swept spectral confocal displacement sensor. Additionally, prism-grating beam splitting is employed to simulate and analyze the imaging spectrometer's back end. The combination of a prism and a grating eliminates the spectral line bending that occurs in the imaging spectrometer. The results indicate that a complete optical pathway for the line-scanning spectral confocal displacement sensor has been built, achieving an axial resolution of 0.8 mu m, a scanning line length of 24 mm, and a dispersion range of 3.9 mm. This sensor significantly expands the range of measurements and fills a previously unaddressed gap in the field of analyzing the current stage of line-scanning spectral confocal displacement sensors. This is a groundbreaking achievement for both the sensor itself and the field it operates in. The line-scanning spectral confocal displacement sensor's design addresses a previously unmet need in systematic analysis by successfully obtaining a wide measuring range. This provides systematic theoretical backing for the advancement of the sensor, which has potential applications in the industrial detection of various ranges and complicated objects.</p>2024-03-15T09:08:40ZInteraction semantic segmentation network via progressive supervised learningZhao, RuiniXie, MeilinFeng, XubinGuo, MinSu, XiuqinZhang, Pinghttp://ir.opt.ac.cn:80/handle/181661/972112024-03-18T03:05:11Z2024-03-15T09:08:39Z题名: Interaction semantic segmentation network via progressive supervised learning
作者: Zhao, Ruini; Xie, Meilin; Feng, Xubin; Guo, Min; Su, Xiuqin; Zhang, Ping
摘要: <p>Semantic segmentation requires both low-level details and high-level semantics, without losing too much detail and ensuring the speed of inference. Most existing segmentation approaches leverage low- and high-level features from pre-trained models. We propose an interaction semantic segmentation network via Progressive Supervised Learning (ISSNet). Unlike a simple fusion of two sets of features, we introduce an information interaction module to embed semantics into image details, they jointly guide the response of features in an interactive way. We develop a simple yet effective boundary refinement module to provide refined boundary features for matching corresponding semantic. We introduce a progressive supervised learning strategy throughout the training level to significantly promote network performance, not architecture level. Our proposed ISSNet shows optimal inference time. We perform extensive experiments on four datasets, including Cityscapes, HazeCityscapes, RainCityscapes and CamVid. In addition to performing better in fine weather, proposed ISSNet also performs well on rainy and foggy days. We also conduct ablation study to demonstrate the role of our proposed component. Code is available at: https://github.com/Ruini94/ISSNet</p>2024-03-15T09:08:39ZA novel texture image pyramid based vote strategy in local binary pattern for texture classificationHu, ShiqiPan, ZhibinRen, Xinchenghttp://ir.opt.ac.cn:80/handle/181661/972102024-03-19T01:36:23Z2024-03-15T09:08:37Z题名: A novel texture image pyramid based vote strategy in local binary pattern for texture classification
作者: Hu, Shiqi; Pan, Zhibin; Ren, Xincheng
摘要: <p>In texture classification field, Local Binary Pattern (LBP) is one of the most attractive method because of its robust texture feature extracting capability and low computational cost. However, there are two main shortages need to be solved. Firstly, original LBP extracts texture features in a fixed circle temple and cannot extract multi-scale texture features. Secondly, the recent researches only combine the feature histograms to utilize the complementary texture features extracted by different LBP-based variants. In this paper, aiming to solve these two main shortages, we propose a novel texture image pyramid based vote (TIPbV) strategy in local binary pattern. There are totally three steps in the TIPbV strategy: the preprocessing step, the vote step and the complementary texture feature extraction step. In the first preprocessing step, we build a multi-scale Gaussian texture image pyramid or multi-scale average texture image pyramid from original texture images in different texture databases. In the second vote step, the unanimous vote strategy or the majority vote strategy is utilized to effectively utilize multi-scale texture features extracted by original LBP. In the third complementary texture feature extraction step, we will utilize LBP-based methods to extract the complementary texture features from original texture images. The final training image which has most similar multi-scale and complementary texture features with the testing image will be selected to determine the classification result.</p>2024-03-15T09:08:37ZCoherence analysis of supercontinuum generation in nitrobenzene liquid-core photonic crystal fiber based on adaptive step-size methodsWen, JinLiang, BozhiSun, WeiHe, ChenyaoXiong, KeyuYu, HuiminZhang, HuiWu, ZhengweiWang, Qianhttp://ir.opt.ac.cn:80/handle/181661/972092024-03-19T01:37:39Z2024-03-15T09:08:35Z题名: Coherence analysis of supercontinuum generation in nitrobenzene liquid-core photonic crystal fiber based on adaptive step-size methods
作者: Wen, Jin; Liang, Bozhi; Sun, Wei; He, Chenyao; Xiong, Keyu; Yu, Huimin; Zhang, Hui; Wu, Zhengwei; Wang, Qian
摘要: <p>Methods for solving the generalized nonlinear Schrodinger equation (GNLSE) with adaptive step-size methods including the local error method (LEM) and conservation quantity error method (CQEM) are described. Supercontinuum generation (SCG) in liquid-core photonic crystal fibers (PCF) is numerically simulated by using LEM and CQEM in the time domain and frequency domain (FD) respectively. According to the numerical simulation results, the advantages and disadvantages of different adaptive step-size methods are compared, and the influence of different adaptive step-size methods on the coherence of SC is analyzed. A supercontinuum (SC) spectrum spanning from approximately 1300-2800 nm with high-coherence properties is numerically generated in the 5 cm fiber with 50 fs and 1000 W pump pulses at 1.55 mu m. The numerical results demonstrate that the performance of the SC generated in FD is also better because the nonlinear operator is more effective in FD. In addition, the pulse evolution process based on LEM is smoother and the coherence is better due to its higher number of iterations and accuracy, so it is adapted to accurately modeling the SCG in PCF. However, the CQEM is more computationally efficient and can minimize the computational effort, so it is suitable for the fast modeling of SCG in PCF. This numerical study helps to optimize the numerical process of SCG and find a new way for the generation of highly coherent SC.</p>2024-03-15T09:08:35Z