宽频段振动干扰不敏感的白光干涉测量  

White-light interferometry immune to vibration disturbance over wide frequency region

作　　者：刘乾[1] 密乐 黄小津[1] LIU Qian;MI Le;HUANG Xiaojin(Institute of Machinery Manufacturing Technology,China Academy of Engineering Physics,Mianyang 621999,China)

机构地区：[1]中国工程物理研究院机械制造工艺研究所,四川绵阳621999

出　　处：《光学精密工程》2024年第17期2625-2634,共10页Optics and Precision Engineering

基　　金：国防科工局技术基础科研项目(No.JSZL2022212B001)。

摘　　要：传统白光干涉测量方法对振动干扰非常敏感,振动干扰会引起扫描步长误差,进而降低白光干涉的测量精度。为抑制振动干扰的影响,提出一种三点反正弦的白光干涉测量算法。三点反正弦法将干涉图序列中每相邻三幅分为一组,利用扫描过程中干涉条纹连续移动的特点,从每组干涉图的有效条纹区域计算出相移偏差,进而得到每幅干涉图的实际扫描步长。基于计算的实际扫描步长,构建了非等步长的调制度与相位最小二乘计算方法,并重构表面高度。由于计算步长仅利用三幅干涉图,三点反正弦法频段响应宽,能够探测快变、大幅的扫描步长误差。仿真和实验证实,在振动干扰下三点反正弦法能获得高达0.5%的测量准确性(台阶高度为10μm),并适合多种类构型表面形貌的测量。理论分析和实验表明,三点反正弦法能够抑制多种形式扫描步长误差的影响,适用于宽频段振动干扰下的白光干涉测量。The traditional white-light interferometer is highly sensitive to vibrations,causing scanning step errors and reducing measurement accuracy.To address this,a three-point arcsine(3P-Asin)algorithm is proposed.This method divides WLI interferograms into groups of three adjacent frames,with overlap be⁃tween groups.By analyzing fringe movement,the phase shift deviation and exact scanning step are deter⁃mined.Using this step,a least-squares method calculates phase and modulation for non-equal step scan⁃ning to reconstruct surface height.The 3P-Asin algorithm detects fast and large scanning step errors using only three interferograms,with no approximation.Simulations and experiments show it achieves an accura⁃cy of 0.5%for a 10μm step height and adapts to various surfaces in mechanical machining.Both theoreti⁃cal and experimental results demonstrate that the 3P-Asin algorithm effectively attenuates scanning step errors across a wide frequency range, making it suitable for WLI in vibrating environments.

关 键 词：表面形貌测量 白光干涉测量 粗糙度 振动 

分 类 号：TH742[机械工程—光学工程]