极大似然噪声估计的高动态范围叠层衍射成像术  

High-Dynamic-Range Ptychography Using Maximum Likelihood Noise Estimation

作　　者：李文杰[1] 谷洪刚[1,2] 刘力 钟磊[1] 周玉[1] 刘世元[1,2] Li Wenjie;Gu Honggang;Liu Li;Zhong Lei;Zhou Yu;Liu Shiyuan(State Key Laboratory of Intelligent Manufacturing Equipment and Technology,Huazhong University of Science and Technology,Wuhan 430074,Hubei,China;Optics Valley Laboratory,Wuhan 430074,Hubei,China)

机构地区：[1]华中科技大学智能制造装备与技术全国重点实验室,湖北武汉430074 [2]光谷实验室,湖北武汉430074

出　　处：《激光与光电子学进展》2024年第8期165-171,共7页Laser & Optoelectronics Progress

基　　金：国家自然科学基金(52130504);湖北省重点研发计划(2021BAA013)。

摘　　要：衍射场作为叠层衍射成像技术(ptychography)的重要约束,其信息的丰富度和准确性将直接影响重构质量。提出一种基于极大似然噪声估计的高动态范围(ML-HDR)叠层衍射成像方法,即在探测器线性响应假设下,构建复合高斯噪声模型,根据极大似然估计求解最优权重函数,由多张低动态范围衍射场合成高信噪比衍射场。对比了单次曝光、传统HDR和ML-HDR三种方法的重构质量。仿真和实验结果表明:相比单次曝光,ML-HDR能将动态范围拓宽8位,重构分辨率提升至2.83倍;相比传统HDR,ML-HDR能提高重构图像的均匀性和对比度,且无需额外标定硬件参数。As crucial constraints of ptychography,the richness and accuracy of diffraction patterns directly affect the quality of reconstruction images.This paper proposes a highdynamicrange ptychography using maximum likelihood noise estimation(MLHDR).Herein,assuming the linear response of the detector,a compound Gaussian noise model is established;the weight function is optimized according to the ML estimation;and a high signaltonoise ratio diffraction pattern is further synthesized from multiple low dynamic range diffraction patterns.The reconstruction quality of single exposure,conventional HDR,and MLHDR is compared.The simulation and experiment results show that MLHDR can widen the dynamic range by 8 bits and enhance the reconstruction resolution by 2.83 times compared with the single exposure.Moreover,compared with conventional HDR,MLHDR can enhance the contrast and uniformity of the reconstruction image in the absence of additional hardware parameters.

关 键 词：计算成像 叠层衍射成像术 高动态范围 相位恢复 极大似然估计 

分 类 号：O436[机械工程—光学工程]