基于白光干涉测试技术的改进Carré相移算法  

Improved CarréPhase Shifting Algorithm Based on White Light Interferometry

作　　者：李慧鹏[1] 谭朦曦 朱伟伟[1] 郑晓[1] 李皎[1] 

机构地区：[1]北京航空航天大学仪器科学与光电工程学院,北京100191

出　　处：《光子学报》2016年第6期62-67,共6页Acta Photonica Sinica

基　　金：国家重大仪器设备开发专项(No.2013YQ040877)资助~~

摘　　要：为了减小白光相移干涉法测量物体微观形貌时产生的误差,对极值法的搜索路径进行优化后与Carré相移算法相结合,提出一种基于白光干涉测试技术的改进Carré相移算法.该算法减小了光源扰动及电荷耦合元件散粒噪声带来的影响,且对相移器的线性误差不敏感,免去了相位解包裹过程,提高了运算效率.采用单刻线样块对扫描步距进行校准实现了光源中心波长的在线修正,减小了由于光源特性及环境扰动误差带来的影响.采用不同算法对标准粗糙度样块进行三维形貌恢复以及表面粗糙度的重复性测量实验,结果表明:该算法对表面粗糙度的测量结果较传统白光干涉算法准确度提高,测量重复性优于1%.In order to reduce the error produced by using the white light interferometry while calibrating the microcosmic shape,an improved Carréphase shifting algorithm based on white light interferometry was proposed.The search path of traditional extremum algorithm was optimized,and then combined with the Carréphase shifting algorithm to extract the phase.The proposed algorithm can eliminate the random error caused by the shot-noise of CCD,it do not need to limit the step of the phase adjustments by using the central wavelength of white light and the phase unwrapping is no longer needed,and it makes the computation efficiency improved.The central wavelength on line was modified to reduce the error caused by the characteristic of light and environment disturbance.The three-dimensional topography of standard roughness specimens was restored and the surface roughness was mesuresed by different kinds of algorithms.The experimental results show that,compared with other algorithms,the accuracy is improved and repeatability is better than 1% by using the proposed improved algorithm.

关 键 词：白光干涉 中心波长 线性误差 Carré相移算法 相位解包裹 

分 类 号：TH741[机械工程—光学工程] TH744[机械工程—仪器科学与技术]