基于系统非线性校正与滤波的相位测量  

Phase Measurement Based on Nonlinearity Correction and Filter of System

作　　者：乔闹生 龙永福[2,3] 严波 曹斌芳[3] 黎小琴 QIAO Nao-sheng;LONG Yong-fu;YAN Bo;CAO Bin-fang;LI Xiao-qin(International College of Hunan University of Arts and Science,Changde,Hunan 415000,China;Hunan Province Cooperative Innovation Center for the Construction&Development of Dongting Lake Ecological Economic Zone,Changde,Hunan 415000,China;Mathematics and Physics Science College,Hunan University of Arts and Science,Changde,Hunan 415000,China)

机构地区：[1]湖南文理学院国际学院,湖南常德415000 [2]湖南省洞庭湖生态经济区协同创新中心,湖南常德415000 [3]湖南文理学院数理学院,湖南常德415000

出　　处：《光子学报》2019年第10期94-100,共7页Acta Photonica Sinica

基　　金：国家自然科学基金(Nos.61703157,61475045)~~

摘　　要：相位测量系统中投影仪输出与CCD输入变形条纹光强之间的非线性导致频谱混叠,影响测量精度,为了消除他们之间的非线性关系,提高相位测量精度,分析了系统非线性产生的基本原因,提出了一种基于系统非线性校正与滤波的相位测量方法.首先校正由投影仪中伽马畸变产生的系统非线性,然后采用低通滤波器对校正后输出的频谱进行滤波,只保留频谱中的基频成份,最后采用四步相移法对变形条纹进行相位测量.MATLAB仿真与实际实验结果表明,所提方法的系统非线性校正与滤波效果较好,有助于提高相位测量精度.The nonlinearity between projector output and CCD input deformed fringe intensity in phase measurement system results in spectrum aliasing and affects measurement accuracy.In order to eliminate the nonlinearity relationgship between them and improve phase measurement accuracy,the basic causes of system nonlinearity are analyzed,and a new phase measurement method based on system nonlinearity correction and filtering is proposed.Firstly,the system nonlinearity caused by the gamma distortion in the projector is corrected.Then,the output spectrum is filtered by low-pass filter,only the fundamental frequency component of the spectrum is retained.Finally,the phase measurement of deformed fringes is carried out by four-step phase-shift method.The results of MATLAB simulation and practical experiment show that the proposed method has better effect of system nonlinearity correction and filtering,and is helpful to improve the phase measurement accuracy.

关 键 词：相位测量 非线性校正 低通滤波 四步相移法 条纹投影 

分 类 号：O438.2[机械工程—光学工程]