基于利萨茹椭圆拟合的两步相移轮廓技术  

Two-step phase shifting profilometry based on Lissajous ellipse fitting technique

作　　者：朱进进 吴雨祥 邵晓鹏 Zhu Jin-Jin;Wu Yu-Xiang;Shao Xiao-Peng(School of Physics and Optoelectronic Engineering,Xidian University,Xi’an 710071,China)

机构地区：[1]西安电子科技大学物理与光电工程学院,西安710071

出　　处：《物理学报》2021年第17期65-75,共11页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:61805188);中国博士后科学基金(批准号:2019M653547);陕西省国家自然科学基金(批准号:2019JQ-121);中央高校基本科研业务费(批准号:JB180505)资助的课题.

摘　　要：相移轮廓术(phase shifting profilometry,PSP)至少需要三帧条纹图提取物体的相位信息.在动态测量中,减少条纹数有助于快速测量,并且可以抑制运动物体存在的相移误差.为了克服上述问题,本文提出基于利萨茹椭圆拟合(Lissajous ellipse fitting,LEF)的两步相移轮廓术,针对条纹背景和调制度分布不均匀导致的LEF相位误差,给出了误差抑制方法.实验实现了基于LEF的两步相移动态场景测量,与多帧PSP相比,本文所述方法可以减少条纹帧数并且可抑制物体的运动导致的相移误差.Phase shifting profilometry(PSP)is an effective technique to reconstruct the three-dimensional shape of object.In general,PSP needs three or more fringe patterns with phase-shifting accurately known to extract the phase distribution of objects.Therefore,the scene and the test objects should remain stationary during capturing the fringe patterns.However,the phase shifts may be unknown in an actual PSP measurement system,especially when measuring the moving object,that is,the phase-shift error may be introduced during the obtaining of the phase-shifting fringe patterns of moving object.In the dynamic measurement scenario,the use of fewer fringe patterns can realize the faster measurement speed and suppress the phase shift error introduced by the moving object.In this paper,a two-step PSP algorithm is proposed based on Lissajous ellipse fitting(LEF).The proposed method uses only two fringe patterns to extract the phase distribution of the object and can suppress the phase shift error caused by the moving object.However,in a practical PSP system,the spatiotemporally varying background intensity and modulation also significantly affect the phase accuracy extracted by LEF,and thus three error-suppressing methods are proposed to reduce the phase error caused by the non-uniform background intensity and modulation.In order to verify the effectiveness of the three error-suppressing methods,we analyze and compare their performances of error suppression under different background intensities and modulations.The advantages of three error-suppressing methods can be summarized as follows.1)The mean and modulation correction technique has greater advantage than the other two when the background intensity and modulation vary with time.2)When the background intensity and modulation are relevant to pixel position and the number of fringe patterns,the empirical mode decomposition normalization can more effectively suppress the influence of the non-uniform background intensity and modulation.In experiment,a two-step phase-shifting dy

关 键 词：条纹投影技术 相位重建 相移轮廓术 相移误差 

分 类 号：TP391.41[自动化与计算机技术—计算机应用技术]