基于高阶强度传输方程改进的相位物体层析重建算法  

An Improved Tomographic Reconstruction of Phase Objects Based on High-Order Transport of Intensity Equation

作　　者：程鸿[1] 张晓龙 刘勇 朱啸天 CHENG Hong;ZHANG Xiaolong;LIU Yong;ZHU Xiaotian(College of Electronic Information Engineering, Anhui University, Hefei 230601, Anhui, China)

机构地区：[1]安徽大学电子信息工程学院,安徽合肥230601

出　　处：《华南理工大学学报（自然科学版）》2022年第4期90-99,共10页Journal of South China University of Technology(Natural Science Edition)

基　　金：安徽省高等学校自然科学研究项目(KJ2020ZD02,KJ2019ZD04)。

摘　　要：经典的层析成像方法通常只考虑物体的强度重建,往往丢失了包含物体更多信息的相位。强度传输方程作为一种经典的相位恢复算法,能够直接从强度反演出相位。文中提出了一种能够层析重建物体相位信息的新算法,该算法在高阶强度传输方程的基础上进行改进,通过将高阶强度传输方程求解得到的初始相位值代入多平面迭代来降低系统误差,恢复出具有更高精度的相位结果,再经过滤波反投影重建物体的三维相位信息,在反投影重建过程中加入了旋转中心校正的步骤以使重建结果更为精确。实验结果表明,该算法在解决由于强度微分近似约束造成的相位精度低问题的同时,可以获得高精度的物体三维相位重建结果。Classical tomography methods usually only consider the intensity reconstruction of the object and lose the phase containing more information of the object.As a classical phase retrieval algorithm,the transport of intensity equation can directly calculate the phase from the known intensity.This paper proposed a new algorithm which can reconstruct the phase information of objects by tomography.The proposed algorithm was improved on the basis of high-order transport of intensity equation.It brings the initial phase value obtained from the solution of high-order transport of intensity equation into multi-plane iteration to reduce the system error and retrieve the phase result with higher accuracy.Then the three-dimensional phase information of object was reconstructed through filtered back projection.In the process of back projection reconstruction,the step of rotation center correction was added to make the reconstruction result more accurate.The experimental results show that the algorithm can obtain high precision three-dimensional phase reconstruction results while solving the low phase accuracy caused by intensity differential approximation constraints.

关 键 词：层析成像 高阶强度传输方程 多平面迭代 相位恢复 强度微分 

分 类 号：O436[机械工程—光学工程]