硬x射线同轴相衬成像的相位恢复

基于角谱的概念，分析了硬x射线同轴相衬成像过程，在传统相位恢复算法GS算法的基础上 ，提出了基于角谱传播的相位恢复算法——迭代角谱法（IASA），并利用数值法模拟研究了 相衬成像和相位恢复过程，从理论上验证了这一相位恢复算法. 关键词： 相位恢复 相位衬度 角谱 硬x射线

Phase retrieval for hard x-ray in-line phase contrast imaging

Since hard x_ray in_line phase_contrast imaging is based on Fresnel diffraction of x_ray, we propose to make phase retrieval calculations between arbitrary plan es interrelated through the Fresnel domain. The calculation of the free space pr opagation is based on the angular spectrum approach, which can be used with Gerc hberg_Saxton algorithm for phase retrieval. We call this method the iterative an gular spectrum approach. The new method is tested on simulated images in the cas e of uniform illumination and is demonstrated to be efficient for phase retrieva l.