部分相干光源微分相衬双图像相位恢复  

Dual-images phase retrieval in differential phase-contrast imaging with partial coherence source

作　　者：刘鑫[1] 郭金川[1] 

机构地区：[1]深圳大学光电工程学院,光电子器件与系统教育部重点实验室,深圳518060

出　　处：《深圳大学学报（理工版）》2014年第2期169-173,共5页Journal of Shenzhen University(Science and Engineering)

基　　金：国家自然科学基金资助项目(61101175);深圳市科技计划资助项目(2008340)~~

摘　　要：基于部分相干光成像理论,结合X射线微分相衬成像特点,给出有限大小焦斑光源物体微分相衬成像干涉条纹强度分布.建立基于吸收光栅微分干涉条纹探测模型,该模型给出可见光探测器探测强度表达式.根据光强分布,提出一种新的相位恢复算法,该算法仅需两幅物体曝光图像,相对旧算法,减少了物体曝光次数,有利于减少物体X射线剂量的吸收.X-ray phase contrast imaging techniques can directly detect the structure of soft tissues in the medicine, biology and material sciences because those methods can provide higher sensitivity than the conventional X-ray radio-graphy. Based on the partial coherence theory, the intensity distribution of X-ray interferogram with the source of fi-nite focus is presented. The detecting model of visible light detector with absorption grating is built and relative in-tensity of signal is given also. A new phase retrieval algorithm, which needs only two X-ray images of sample, is pro-posed according to the detecting model. The new algorithm helps reduce the absorption of X-ray dose. The computer simulation has been performed to verify the feasibility of our proposed algorithm.

关 键 词：干涉成像 相位光栅 吸收光栅 X射线 部分相干光源 相位恢复 微分相衬成像 

分 类 号：O434.19[机械工程—光学工程]