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Multi-prior physics-enhanced neural network enables pixel super-resolution and twin-imagefree phase retrieval from single-shot hologram

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Opto-Electronic Advances 2024年第9期7卷 22-38页

作者： Xuan Tian Runze Li Tong Peng Yuge Xue Junwei Min xing Li Chen Bai Baoli Yao State Key Laboratory of Transient optics and Photonics Xi’an Institute of Optics and Precision MechanicsChinese Academy of SciencesXi’an 710119China University of Chinese Academy of Sciences Beijing 100049China.

Digital in-line holographic microscopy(DIHM)is a widely used interference technique for real-time reconstruction of living cells’morphological information with large space-bandwidth product and compact ***,the need for a larger pixel size of detector to improve imaging photosensitivity,field-of-view,and signal-to-noise ratio often leads to the loss of sub-pixel information and limited pixel ***,the twin-image appearing in the reconstruction severely degrades the quality of the reconstructed *** deep learning(DL)approach has emerged as a powerful tool for phase retrieval in DIHM,effectively addressing these ***,most DL-based strategies are datadriven or end-to-end net approaches,suffering from excessive data dependency and limited generalization ***,a novel multi-prior physics-enhanced neural network with pixel super-resolution(MPPN-PSR)for phase retrieval of DIHM is *** encapsulates the physical model prior,sparsity prior and deep image prior in an untrained deep neural *** effectiveness and feasibility of MPPN-PSR are demonstrated by comparing it with other traditional and learning-based phase retrieval *** the capabilities of pixel super-resolution,twin-image elimination and high-throughput jointly from a single-shot intensity measurement,the proposed DIHM approach is expected to be widely adopted in biomedical workflow and industrial measurement.

关键词： optical microscopy quantitative phase imaging digital holographic microscopy deep learning super-resolution

Slicing of large-size single crystals by ultrafast laser with external stress assistance

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Chinese optics Letters 2024年第8期22卷 100-105页

作者： Lifeng Wang Lili Liu Yinan Wang Xun Li Chenchen Li Ming Li State Key Laboratory of Transient optics and Photonics Xi’an Institute of Optics and Precision MechanicsChinese Academy of SciencesXi’an 710119China University of Chinese Academy of Sciences Beijing 100049China

The existing single-crystal slicing techniques result in significant material wastage and elevate the production cost o premium-quality thin slices of *** we report(for the first time,to our knowledge)an approach for vertical slicin of large-size single-crystal gain materials by ultrafast *** employing aberration correction techniques,the optimi zation of the optical field distribution within the high-refractive-index crystal enables the achievement of a continuou laser-modified layer with a thickness of less than 10μm,oriented perpendicular to the direction of the laser direction The compressed focal spot facilitates crack initiation,enabling propagation under external forces,ultimately achievin the successful slicing of aΦ12.mm *** surface roughness of the sliced Yb:YAG is less than 2.5μ*** result illustrate the potential of low-loss slicing strategy for single-crystal fabrication and pave the way for the future develop ment of thin disk lasers.

关键词： single-crystal gain materials ultrafast laser slicing YAG aberration correction

Spectral-interferometry-based diff-iteration for high-precision micro-dispersion measurement

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Photonics Research 2024年第6期12卷 1362-1370页

作者： WEI DU JINGSHENG HUANG YANG WANG MAOZHONG ZHAO JUAN LI JUNTAO HE JINDONG WANG WENFU ZHANG TAO ZHU Key Laboratory of Optoelectronic Technology&System(Ministry of Education) Chongqing UniversityChongqing 400044China State Key Laboratory of Transient optics and Photonics Xi’an Institute of Optics and Precision MechanicsChinese Academy of SciencesXi’an 710119China

Precise measurement of micro-dispersion for optical devices(optical fiber,lenses,etc.)holds paramount significance across domains such as optical fiber communication and dispersion interference ***,due to its complex system,complicated process,and low reliability,the traditional dispersion measurement methods(interference,phase shift,or time delay methods)are not suitable for the accurate measurement of micro-dispersion in a wide spectral ***,we propose a spectral-interferometry-based diff-iteration(SiDi)method for achieving accurate wide-band micro-dispersion *** an optical frequency comb,based on the phase demodulation of the dispersion interference spectrum,we employ the carefully designed SiDi method to solve the dispersion curve at any position and any *** approach is proficient in precisely measuring micro-dispersion across a broadband spectrum,without the need for cumbersome wavelength scanning processes or reliance on complex high-repetition-rate combs,while enabling adjustable *** efficacy of the proposed method is validated through simulations and *** employed a chip-scaled soliton microcomb(SMC)to compute the dispersion curves of a 14 m single-mode fiber(SMF)and a 0.05 m *** to a laser interferometer or the theoretical value given by manufacturers,the average relative error of refractive index measurement for single-mode fiber(SMF)reaches 2.8×10^(-6) and for glass reaches 3.8×10^(-6).The approach ensures high precision,while maintaining a simple system structure,with realizing adjustable resolution,thereby propelling the practical implementation of precise measurement and control-dispersion.

关键词： interferometer dispersion iteration

Multilevel Attention Unet Segmentation Algorithmfor Lung Cancer Based on CT Images

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Computers, Materials & Continua 2024年第2期78卷 1569-1589页

作者： Huan Wang Shi Qiu Benyue Zhang Lixuan xiao xi’an institute of optics and {2. mechanics Chinese Academy of SciencesXi’anChina School of Biomedical Engineering Fourth Military Medical UniversityXi’anChina University of Illinois at Urbana Champion ChampaignUSA

Lung cancer is a malady of the lungs that gravely jeopardizes human ***,early detection and treatment are paramount for the preservation of human *** computed tomography(CT)image sequences can explicitly delineate the pathological condition of the *** meet the imperative for accurate diagnosis by physicians,expeditious segmentation of the region harboring lung cancer is of utmost *** utilize computer-aided methods to emulate the diagnostic process in which physicians concentrate on lung cancer in a sequential manner,erect an interpretable model,and attain segmentation of lung *** specific advancements can be encapsulated as follows:1)Concentration on the lung parenchyma region:Based on 16-bit CT image capturing and the luminance characteristics of lung cancer,we proffer an intercept histogram algorithm.2.Focus on the specific locus of lung malignancy:Utilizing the spatial interrelation of lung cancer,we propose a memory-based Unet architecture and incorporate skip connections.3)Data Imbalance:In accordance with the prevalent situation of an overabundance of negative samples and a paucity of positive samples,we scrutinize the existing loss function and suggest a mixed loss *** results with pre-existing publicly available datasets and assembled datasets demonstrate that the segmentation efficacy,measured as Area Overlap Measure(AOM)is superior to 0.81,which markedly ameliorates in comparison with conventional algorithms,thereby facilitating physicians in diagnosis.

关键词： Lung cancer computed tomography computer-aided diagnosis Unet segmentation

Mural Anomaly Region Detection Algorithm Based on Hyperspectral Multiscale Residual Attention Network

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Computers, Materials and Continua 2024年第1期81卷 1809-1833页

作者： Guo, Bolin Qiu, Shi Zhang, Pengchang Tang, xingjia Key Laboratory of Spectral Imaging Technology cas Xi'an Institute of Optics and Precision Mechanics Chinese Academy of Sciences Xi'an 710119 China School of Optoelectronics University of Chinese Academy of Sciences Beijing 100408 China institute of Culture and Heritage Northwest Polytechnic University Xi'an 710072 China

Mural paintings hold significant historical information and possess substantial artistic and cultural ***, murals are inevitably damaged by natural environmental factors such as wind and sunlight, as well as by human activities. For this reason, the study of damaged areas is crucial formural restoration. These damaged regions differ significantly from undamaged areas and can be considered abnormal targets. Traditional manual visual processing lacks strong characterization capabilities and is prone to omissions and false detections. Hyperspectral imaging can reflect the material properties more effectively than visual characterization methods. Thus, this study employs hyperspectral imaging to obtain mural information and proposes a mural anomaly detection algorithm based on a hyperspectral multi-scale residual attention network (HM-MRANet). The innovations of this paper include: (1) Constructing mural painting hyperspectral datasets. (2. Proposing a multi-scale residual spectral-spatial feature extraction module based on a 3D CNN (Convolutional Neural Networks) network to better capture multiscale information and improve performance on small-sample hyperspectral datasets. (3) Proposing the Enhanced Residual Attention Module (ERAM) to address the feature redundancy problem, enhance the network's feature discrimination ability, and further improve abnormal area detection accuracy. The experimental results show that theAUC(AreaUnderCurve), Specificity, andAccuracy of this paper's algorithmreach 85.42., 88.84%, and 87.65%, respectively, on this dataset. These results represent improvements of 3.07%, 1.11% and 2.68% compared to the SSRN algorithm, demonstrating the effectiveness of this method for mural anomaly detection. © 2.2. The Authors. Published by Tech Science Press.

关键词： Convolutional neural networks

The Active Compensation Technique for Large Reflector Antennas Based on Quadratic Curve Fitting

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Research in Astronomy and Astrophysics 2024年第7期24卷 226-234页

作者： Tian-xiang Zheng Bin-Bin xiang Han-Wei Cui Wei Wang Pei-Yuan Lian Shang-Ming Lin Yang Zhang Jian-Ping Zhou Kai Li School of Mechanical Engineering Xinjiang UniversityUrumqi 830017China School of Mechano-Electronic Engineering Xidian UniversityXi’an 710017China xi’an institute of optics and {2. mechanics Chinese Academy of SciencesXi’an 710119China

Active reflectors are often used to compensate the surface distortion caused by environmental factors that degrade the electromagnetic performance of large high-frequency reflector *** is crucial for maintaining high gain operation in antennas.A distortion compensation method for the active reflector of a large dual-reflector antenna is proposed.A relationship is established between the surface deformation and the optical path difference for the primary reflector by geometric ***,employing finite element analysis,a polynomial fitting approach is used to describe the impact of adjusting points on the reflector surface based on the coordinates of each *** standardizing the positions of various panels on the reflector,the fitting ns can be applied to the reflector panels of similar ***,based on the distribution characteristics of the primary reflector panels,the adjustment equation for the actuators is derived by the influence matrix *** can be used to determine the adjustment amount of actuators to reduce the rms of the optical path ***,the least squares method is employed to resolve the matrix *** example of a 110 m aperture dual-reflector antenna is carried out by finite element analysis and the proposed *** results show that the optical path difference is reduced significantly at various elevation cases,which indicates that the proposed method is effective.

关键词： Methods analytical-Methods numerical-Telescopes

Preparation and improved energy storage capability of nanocomposites utilizing ultrathin 2. HfO_(2.@TiO_(2.nanosheets

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Journal of Advanced Dielectrics 2024年第2期14卷 42-53页

作者： Chao Chen Chen Guo xiaoyong Wei Pengfei Wang xi’an institute of optics and {2. mechanics Chinese Academy of Sciences(cas) Xi’an 710119China Electronic Materials Research Laboratory Key Laboratory of the Ministry of Education and International Center for Dielectric ResearchXi’an Jiaotong University Xi’an 710049China

Polymer-based dielectrics play an important role in electrostatic capacitor by their high energy density(U_(e))and ***,we designed a simple high Ue polymer-based dielectrics by controlling the morphology and surface modification of inorganic *** decrease the difference in dielectric properties between fillers and matrix of the nanocomposites,HfO_(2.acting as the buffer layer with high insulation and appropriate permittivity coated onto the surface of TiO_(2.nanosheets(TiO_(2.Ns)to form a core–shell *** introduction of HfO_(2.@TiO_(2.nanosheets(HfO_(2.@TiO_(2.Ns)makes the nanocomposite with higher dielectric permittivity and lower dielectric loss than poly(vinylidene fluoride-co-hexafluoropropylene)(P(VDF-HFP))*** addition,the HfO_(2.@TiO_(2.Ns can establish an efficient barrier to limit the space charge conduction,hamper the growing electric trees,and the HfO_(2.layer with high insulation could hinder the mobility of charge *** breakdown strength(Eb)of nanocomposite is superior to that of polymer matrix.A small addition of 3 wt.%HfO_(2.@TiO_(2.Ns into P(VDF-HFP)matrix can raise the Eb to 480.7MV/m and present a maximum discharged Ue of 13.9 J/*** work demonstrates that it is an effective strategy to improve the Ue via designing the structure and surface state of inorganic filler simultaneously.

关键词： Nanosheets nanocomposite dielectrics passivation layer breakdown strength energy density

Two-dimensional localized modes in nonlinear systems with linear nonlocality and moiré lattices

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Frontiers of physics 2024年第4期19卷 265-273页

作者： xiuye Liu Jianhua Zeng Center for Attosecond Science and Technology State Key Laboratory of Transient Optics and PhotonicsXi’an Institute of Optics and Precision Mechanics of Chinese Academy of SciencesXi’an 710119China University of Chinese Academy of Sciences Beijing 100049China Collaborative lnnovation Center of Extreme optics Shanxi UniversityTaiyuan 030006China

Periodic structures structured as photonic crystals and optical lattices are fascinating for nonlinear waves engineering in the optics and ultracold atoms ***éphotonic and optical lattices—two-dimensional twisted patterns lie somewhere in between perfect periodic structures and aperiodic ones—are a new emerging investigative tool for studying nonlinear localized waves of diverse ***,a theory of two-dimensional spatial localization in nonlinear periodic systems with fractional-order diffraction(linear nonlocality)and moiréoptical lattices is ***,the flat-band feature is well preserved in shallow moiréoptical lattices which,interact with the defocusing nonlinearity of the media,can support fundamental gap solitons,bound states composed of several fundamental solitons,and topological states(gap vortices)with vortex charge s=1 and 2.all populated inside the finite gaps of the linear Bloch-wave *** the linear-stability analysis and direct perturbed simulations,the stability and instability properties of all the localized gap modes are surveyed,highlighting a wide stability region within the first gap and a limited one(to the central part)for the third *** findings enable insightful studies of highly localized gap modes in linear nonlocality(fractional)physical systems with shallow moirépatterns that exhibit extremely flat bands.

关键词： moiréoptical lattices gap solitons and vortices ultracold atoms Gross-Pitaevskii/nonlinear fractional Schrödinger equation nonlinear fractional systems

PDE Standardization Analysis and Solution of Typicalmechanics Problems

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Computer Modeling in Engineering & Sciences 2024年第10期141卷 171-186页

作者： Ningjie Wang Yihao Wang Yongle Pei Luxian Li State Key Laboratory for Strength and Vibration of Mechanical Structures Shaanxi Key Laboratory of Environment and Control for Flight VehicleSchool of Aerospace EngineeringXi’an Jiaotong UniversityXi’an710049China xi’an institute of optics and {2. mechanics of Chinese Academy of Sciences Xi’an710119China

A numerical approach is an effective means of solving boundary value problems(BVPs).This study focuses on physical problems with general partial differential equations(PDEs).It investigates the solution approach through the standard forms of the PDE module in *** typical mechanics problems are exemplified:The deflection of a thin plate,which can be addressed with the dedicated finite element module,and the stress of a pure bending beamthat cannot be *** procedure for the two problems regarding the three standard forms required by the PDE module is *** results were in good agreement with the literature,indicating that the PDE module provides a promising means to solve complex PDEs,especially for those a dedicated finite element module has yet to be developed.

关键词： Three standard forms expression input PDE module deflection solution stress solution