1 中国科学院上海光学精密机械研究所高功率激光物理联合实验室，上海 201800
2 中国科学院中国工程物理研究院高功率激光物理联合实验室，上海 201800
3 中国科学院重大科技任务局，北京 100864
近些年新出现的层叠相位重建引擎（PIE）是一种能够有效解决相位测量难题的无透镜成像技术，相比于传统的相干衍射成像技术，PIE技术具备更高的重建精度、更好的收敛性。由于理论上具备可无限拓展的视场范围、超高分辨能力和对噪声的强鲁抗性，PIE目前被广泛应用于各种相位成像和相位测量领域。讨论了PIE技术提出的背景和核心原理，同时总结了近些年该类算法的主要技术突破，特别地，讨论了PIE技术在X射线、电子束和可见光波段成像领域的关键节点。此外，还总结了在其他领域中基于PIE技术的变形算法，并对将来可能的技术突破点和所面临的挑战进行了讨论。
相位恢复 层叠相位重建 波前重建 迭代计算 光学检测 波前诊断 超快测量 激光与光电子学进展
2022, 59(22): 2200001
Yingming Xu 1,2,3Xingchen Pan 1,2,4,*Mingying Sun 1,2,5,*Wenfeng Liu 1,2[ ... ]Jianqiang Zhu 1,2
Author Affiliations
Abstract
1 Key Laboratory of High Power Laser and Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
2 National Laboratory on High Power Laser and Physics, China Academy of Engineering Physics, Chinese Academy of Sciences, Shanghai 201800, China
3 University of Chinese Academy of Sciences, Beijing 100049, China
4 e-mail: shizizuo111@163.com
5 e-mail: sunmy@siom.ac.cn
Classic interferometry was commonly adopted to realize ultrafast phase imaging using pulsed lasers; however, the reference beam required makes the optical structure of the imaging system very complex, and high temporal resolution was reached by sacrificing spatial resolution. This study presents a type of single-shot ultrafast multiplexed coherent diffraction imaging technique to realize ultrafast phase imaging with both high spatial and temporal resolutions using a simple optical setup, and temporal resolution of nanosecond to femtosecond scale can be realized using lasers of different pulse durations. This technique applies a multiplexed algorithm to avoid the data division in space domain or frequency domain and greatly improves the spatial resolution. The advantages of this proposed technique on both the simple optical structure and high image quality were demonstrated by imaging the generation and evaluating the laser-induced damage and accompanying phenomenon of laser filament and shock wave at a spatial resolution better than 6.96 μm and a temporal resolution better than 10 ns.
Photonics Research
2022, 10(8): 1937
1 中国科学院上海光学精密机械研究所高功率激光物理联合实验室, 上海 201800
2 中国科学院中国工程物理研究院高功率激光物理联合实验室, 上海 201800
3 中国科学院大学, 北京 100049
激光光束质量因子(M2)是全面表征激光光束质量的一个技术评价指标。提出了一种基于振幅调制的M2测量方法,该方法通过记录单幅激光光斑就可以利用迭代计算重建光束的复振幅;进而根据标量衍射理论,可以得到沿光束传输方向任意截面位置的光束强度分布;最后由二阶矩和双曲线拟合方法计算M2因子。模拟和实验验证了所提方法的有效性,且该实验技术简单、快速,不需要复杂的机械扫描结构,适用于脉冲激光光束质量的测量。
激光技术 相干振幅调制成像 图像重建 二阶矩拟合 M2因子 中国激光
2021, 48(17): 1705003
1 中国科学院高功率激光物理重点实验室, 中国科学院上海光学精密机械研究所, 上海 201800
2 中国科学院中国工程物理研究院高功率激光物理联合实验室, 上海 201800
将相干调制成像(CMI)迭代过程等效为梯度搜索算法,建立了CMI收敛模型,从解方程角度提出为保证重建结果的唯一性需要满足的基本条件,即有调制板时光斑非0点数是无调制板时光斑非0点数的2倍,或有调制板时放大λL(λ为波长, L为衍射距离)倍后的调制板频谱截止宽度与无调制板时光斑截止宽度的比值至少为0.414。通过模拟计算进行了很好的验证。该研究为CMI的进一步优化提供了理论依据。
成像系统 相位恢复 相干衍射成像 相干调制成像 迭代算法 光学学报
2020, 40(18): 1811001
1 中国科学院上海光学精密机械研究所高功率激光物理联合实验室, 上海 201800
2 中国科学院中国工程物理研究院高功率激光物理联合实验室, 上海 201800
3 中国科学院大学, 北京 100049
提出一种大倾角照明条件下的高精度PIE(ptychographic iterative engine)迭代重建算法。该算法用小角度照明的透射光代替大角度照明的透射光,通过修正角谱传递函数,得到适应大角度迭代的光场传输公式。在非傍轴条件下,该算法能够避免样品面上相位分布欠采样的问题,同时精确计算衍射面上的衍射光斑,为单次曝光PIE成像的进一步发展和实际应用解决了最为关键的技术难题。
衍射 相干衍射成像 相位测量 光学传递函数 光学学报
2020, 40(17): 1705001
1 中国科学院上海光学精密机械研究所, 中国科学院高功率激光物理重点实验室, 上海 201800
2 中国科学院中国工程物理研究院高功率激光物理联合实验室, 上海 201800
3 中国科学院上海高等研究院, 上海同步辐射光源, 上海 201204
Ptychography是近些年快速发展起来的一种新型相位恢复技术,通过对待测样品以小于照明光直径的步长扫描后,利用迭代计算可以重建出照明光和样品复振幅分布,是一种理论分辨率为衍射极限的非透镜相位成像技术。虽然其提出初期受限于基本假定条件,但近些年随着相关研究的跟进,人们对Ptychography算法特性的理解逐渐深入,算法也日趋成熟,在可见光、X射线和电子束等领域已被广泛应用于相位成像、波前诊断和光学计量,因此针对影响重建过程和精度的关键因素,如模态多样化、扫描误差、光斑误差、距离误差、样品厚度不可忽略等进行了总结,并讨论了针对上述问题的关键技术进展。
成像系统 相位恢复 相干衍射成像 层叠扫描相干衍射成像 迭代计算
Author Affiliations
Abstract
1 Joint Laboratory on High-Power Laser and Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
2 Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
A three-wavelength coherent-modulation-imaging (CMI) technique is proposed to simultaneously measure the fundamental, second and third harmonics of a laser driver in one snapshot. Laser beams at three wavelengths (1053 nm, 526.5 nm and 351 nm) were simultaneously incident on a random phase plate to generate hybrid diffraction patterns, and a modified CMI algorithm was adopted to reconstruct the complex amplitude of each wavelength from one diffraction intensity frame. The validity of this proposed technique was verified using both numerical simulation and experimental analyses. Compared to commonly used measurement methods, this proposed method has several advantages, including a compact structure, convenient operation and high accuracy.
high-power laser pulses phase retrieval wave diagnosis High Power Laser Science and Engineering
2019, 7(3): 03000e48
Author Affiliations
Abstract
1 Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
2 University of Chinese academy of sciences, Beijing 100049, China
3 Department of Engineering Technology and Science, Higher Colleges of Technology, Fujairah 4114, United Arab Emirates
We propose a lens-free coherent modulation imaging (CMI) method for reconstructing a general complex-valued wave field from a single frame of a diffraction pattern. A numerical Fourier transform is introduced in the iterative reconstruction process to replace the lens or zone plate used in the current CMI technique to adopt the constraint on the Fourier components of the exit wave field of the sample. While the complexity of the experimental setup is remarkably reduced by replacing the zone plate and additional accessories with the numerical processing, the energy fluence loss induced by the undesired diffraction orders of the zone plate can be also avoided. The feasibility of the proposed technique is verified experimentally with visible light.
Collection Of theses on high power laser and plasma physics
2016, 14(1): 071203
Author Affiliations
Abstract
1 Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
2 University of Chinese academy of sciences, Beijing 100049, China
3 Department of Engineering Technology and Science, Higher Colleges of Technology, Fujairah 4114, United Arab Emirates
We propose a lens-free coherent modulation imaging (CMI) method for reconstructing a general complex-valued wave field from a single frame of a diffraction pattern. A numerical Fourier transform is introduced in the iterative reconstruction process to replace the lens or zone plate used in the current CMI technique to adopt the constraint on the Fourier components of the exit wave field of the sample. While the complexity of the experimental setup is remarkably reduced by replacing the zone plate and additional accessories with the numerical processing, the energy fluence loss induced by the undesired diffraction orders of the zone plate can be also avoided. The feasibility of the proposed technique is verified experimentally with visible light.
100.5070 Phase retrieval 050.1970 Diffractive optics 120.5050 Phase measurement 070.0070 Fourier optics and signal processing Collection Of theses on high power laser and plasma physics
2016, 14(1): 071203
Author Affiliations
Abstract
1 中国科学院上海光学精密机械研究所高功率激光物理联合实验室, 上海 201800
2 中国科学院大学, 北京 100049
As a newly developed lensless imaging technique, PIE (ptychographical iterative engine) does not only maintain the simplicity and convenience of the equipment of traditional coherent diffraction imaging (CDI) methods, but also overcomes the drawbacks such as restricted field of view and slow convergence. With the extensible imaging field, better convergence speed and higher immunization capability to noise, PIE is widely researched and used in optical, X-ray and electron beam imaging fields. PIE is a new method which is possible to replace the current phase imaging methods. The background, development, applications, problems and developing trend of the PIE method are introduced.
成像系统 相干衍射成像 迭代算法 相位恢复 imaging systems PIE PIE coherent diffraction imaging iterative algorithm phase retrieval Collection Of theses on high power laser and plasma physics
2016, 14(1): 0609001
