基于迭代优化的两帧随机相移干涉术  

Two Step Phase-shifting Interferometry by Least Squares Iterative Optimization

作　　者：刘畅 杜虎兵[1] 冯雷洁 严兴旭 张高鹏[2] LIU Chang;DU Hubing;FENG Leijie;YAN Xingxu;ZHANG Gaopeng(School of Mechatronic Engineering,Xi'an Technological University,Xi'an 710021,China;Xi'an Institute of Optics and Precision Mechanics,Chinese Academy of Sciences,Xi'an 710119,China)

机构地区：[1]西安工业大学机电工程学院,西安710021 [2]中国科学院西安光学精密机械研究所,西安710119

出　　处：《光子学报》2023年第2期21-30,共10页Acta Photonica Sinica

基　　金：国家自然科学基金(No.51975448);陕西省重点研发计划(No.2021GY-274);中国科学院青年创新促进会会员项目(No.2022410)。

摘　　要：提出了一种由粗及精的无需预滤波的两帧先进迭代随机相移技术。基于最小化残差背景,首先利用采集条纹图的相关运算,在近似正交条件下估计相移和相位;然后利用这些求解过程中的中间参数在空域由条纹图数据估计相移和背景;最后,迭代上述过程直至收敛到预定义的精度,从而实现相位的精确求解。针对条纹图空域背景和振幅变化问题,利用条纹图子图降低背景空域变化对背景和相移估计的影响,并减小运算量。与现有的方法相比,本文方法由于提供了正确的初值,具有收敛快、计算快的特点。本文方法简单可靠,是一种实用的两帧相移干涉方法。The temporal phase shifting technique is a powerful tool that is used in numerous industrial,research and development applications,such as range acquisition,industrial inspection,reverse engineering,and object recognition.However,the accuracy of temporal phase shifting technique is limited by the phase-shifting uncertainties resulting from the imperfect conditions in the real testing environments,such as the miscalibration.So,there is a strict requirement on the precision of the phase shifter.To remove this requirement,there have been reported works about phase reconstruction with only two frames.Twoshot phase reconstruction,i.e.,the recovery of a complex-valued signal from two intensity patterns that are nearly identical apart from a random and unknown phase shift between them,which can reconstruct the phase without local sign ambiguity using the minimum number of interferograms with higher measurement accuracy than the single-frame algorithm,is especially prevalent in imperfect testing conditions where requires reducing the detrimental effects on the measurements from mechanical vibrations,ambient air turbulence,and temperature changes.In the implementation of the technique,the filtering procedure of the fringe normalization,background removal,or noise reduction must be applied to the two arbitrarily phase shifted patterns before the phase demodulation.However,due to certain experimental imperfections of any physical system that are hard to model accurately,we cannot assume any particular behavior for the intensity pattern in a general case.In this case,the two-shot phase reconstruction technique may have an unsatisfactory filtering effect during the phase demodulation.Recently,much special attention is paid to the algorithm that does not require pre-filtering.In this work,we proposed a novel two-shot phase reconstruction method that can bypass the pre-filtering with the help of the least squares iterative phase shifting algorithm.In our method,a rough estimation of the phase shift is obtained by correlation op

关 键 词：迭代相移算法 两帧相移技术 随机相移 干涉 相位 

分 类 号：O439[机械工程—光学工程]