调查和研究了现有IGZO薄膜制备工艺，改善了成膜均一性及稳定性，进一步稳定了阈值电压，提升了器件稳定性。首先，通过调整IGZO成膜设备掩膜版的位置，改善基板边缘IGZO膜厚偏薄的状况，提升整面基板阈值电压的均一性；然后，通过分析磁控溅射成膜中磁铁摆动角度的调整对IGZO成膜均一性的影响，确定最优的成膜方式，有效改善阈值电压分布。最后，针对不同氧分压成膜条件，结合残余气体分析，进一步分析研究成膜过程中气体组分，尤其氧气对阈值电压稳定性的影响。研究发现，改善基板边缘及整面IGZO膜厚的均一性，可有效提升TFT器件阈值电压的均一性；控制IGZO成膜过程中氧分压波动，可提高阈值电压的稳定性。
氧化铟镓锌成膜 阈值电压 均一性 稳定性 IGZO film feedthrough voltage uniformity stability
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 装备发展部某中心，北京 100034
随着能量输出能力的不断提升，高功率激光驱动器运行对光学元件的性能和打靶光束的质量都有了更高要求。传统测量仪器结构复杂、精度有限，难以满足实验需求。朱健强课题组将计算成像技术引入到高功率激光驱动器的参数测量中，精确测量大口径光学元件的形貌、应力分布、热畸变等特征，脉冲光束的时间、空间、近远场分布等参量，以及激光与物质相互作用的过程；进一步发展相干衍射成像（CDI）技术，开发出单次曝光三维PIE（ptychography iterative engine）技术、多模态相干调制成像（CMI）技术、分束编码成像技术等，建立了相干衍射成像技术的解析模型，在数学上分析了CDI技术解的唯一性。本文主要综述了课题组在惯性约束聚变中计算光学成像技术应用方面的研究进展。
计算成像 相位测量 激光束表征 激光放大器 光学学报
2023, 43(22): 2200001
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 中国科学院大学材料与光电研究中心，北京 100049
在迭代重建光学传递函数（OTF）测量法中，采集了多幅图像并进行更新计算，因而其具有抗噪声鲁棒性强和抗混叠等优点。然而，在图像采集过程中，不可避免的振动会引起多幅图像之间存在微小的相对平移，进而导致迭代计算次数增加和调制传递函数（MTF）测量结果准确性下降。该测量方法采集到的图像为随机排布的多个点扩散函数（PSF），多幅图像之间无法应用相位相关法来计算相对平移。鉴于此，提出了一种基于相位传递函数（PTF）的多幅图像相对平移校准方法。将每一幅图像单次计算的PTF分别减去第一幅图像单次计算的PTF，根据该差值校准多幅图像之间的相对平移。数值仿真和实验研究结果表明，所提方法的计算精度与图像相对平移的大小无关，至多能够将迭代次数减少80%，并将MTF测量的均方误差降低1~2个数量级。
测量 光学传递函数 调制传递函数 相位传递函数 相位相关法 光学测量 光学学报
2022, 42(19): 1912002
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 National Laboratory on High Power Laser and Physics, Shanghai 201800, China
2 Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
3 Shanghai Institute of Laser Plasma, Chinese Academy of Engineering and Physics, Shanghai 201800, China
In this paper, we review the status of the multifunctional experimental platform at the National Laboratory of High Power Laser and Physics (NLHPLP). The platform, including the SG-II laser facility, SG-II 9th beam, SG-II upgrade (SG-II UP) facility, and SG-II 5 PW facility, is operational and available for interested scientists studying inertial confinement fusion (ICF) and a broad range of high-energy-density physics. These facilities can provide important experimental capabilities by combining different pulse widths of nanosecond, picosecond, and femtosecond scales. In addition, the SG-II UP facility, consisting of a single petawatt system and an eight-beam nanosecond system, is introduced including several laser technologies that have been developed to ensure the performance of the facility. Recent developments of the SG-II 5 PW facility are also presented.
high-power laser facility inertial confinement fusion solid-state amplifier High Power Laser Science and Engineering
2018, 6(4): 04000e55
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
