光谱共焦法偏心下径向梯度折射率透镜的厚度测量  

Thickness measurement of radial gradient index lens under eccentricity by spectral confocal method

作　　者：李春艳 李庚鹏 刘继红 罗豆 刘佳奕 LI Chunyan;LI Gengpeng;LIU Jihong;LUO Dou;LIU Jiayi(Institute of Electronic Engineering,Xi’an University of Posts&Telecommunication,Xi'an 710121,China)

机构地区：[1]西安邮电大学电子工程学院,陕西西安710121

出　　处：《光学精密工程》2022年第17期2067-2076,共10页Optics and Precision Engineering

基　　金：国家自然科学基金资助项目(No.61805199);陕西省自然科学基金资助项目(No.2022JM-387);陕西省重点研发计划资助项目(No.2020GY-127);陕西省教育厅专项科研计划资助项目(No.20JK0908);西安市科技计划项目资助项目(No.2020KJRC0112)。

摘　　要：为了实现径向梯度折射率(GRIN)透镜厚度的准确测量,对偏心引起的径向GRIN透镜厚度测量误差进行了研究。介绍了光谱共焦厚度测量系统的工作原理,利用径向GRIN透镜的光线径迹方程,在笛卡尔坐标系下结合光学拉格朗日函数、光线弧微分方程等,建立了径向GRIN透镜的厚度测量模型。然后,对径向GRIN透镜偏心引起的光谱曲线谱峰漂移,进而造成的厚度测量误差进行了理论研究及仿真分析,并通过搭建实验平台,利用精密位移台驱动GRIN透镜来模拟透镜偏心,完成了偏心影响下的厚度测量。实验结果表明:径向GRIN透镜的偏心程度越大,引起的测量误差越大,轴向测量位置的影响可忽略不计,验证了理论分析的正确性;实际厚度为4.0126 mm的GRIN透镜,校正偏心后的厚度测量误差为4.6μm,验证了光谱共焦法能够实现径向GRIN透镜厚度的精密测量。To accurately measure the thickness of the radial GRIN lens,the measurement error caused by eccentricity was studied.First,the working principle of the spectral confocal thickness measurement system was introduced.Then,the thickness measurement model for the radial GRIN lens was established by using the ray trace equation,optical Lagrange function,and ray arc differential equation in the Cartesian coordinate system.The thickness measurement error caused by the eccentricity of the radial GRIN lens was analyzed through theoretical research and simulation,and the experimental platform was built.The thickness measurement was completed by using the precision displacement table to drive the GRIN lens to simulate lens eccentricity.The experimental results show that the thickness measurement error of radial GRIN lens increases with the eccentricity.The influence of axial measurement position on the thickness measurement is negligible.The accuracy of the theoretical analysis is verified.The thickness measurement error of the GRIN lens with an actual thickness of 4.0126 mm is 4.6μm after correcting for eccentricity.This indicates that the spectral confocal method can realize the precise measurement of radial GRIN lens thickness.

关 键 词：光谱共焦法 厚度测量 径向梯度折射率透镜 偏心 峰值漂移 

分 类 号：O433.1[机械工程—光学工程]