基于光谱共焦的碱金属气室壁厚测量传感器的线性色散物镜设计  

Design of linear dispersive objective lens for measuring sensor for wall thickness of alkali metal gas chamber based on spectral confocal

作　　者：孙飞 董祥美[1] SUN Fei;DONG Xiangmei(School of Optical-Electrical and Computer Engineering,University of Shanghai for Science and Technology,Shanghai 200093,China)

机构地区：[1]上海理工大学光电信息与计算机工程学院,上海200093

出　　处：《光学技术》2021年第2期144-148,共5页Optical Technique

基　　金：国家重点研发计划“地球观测与导航”重点专项(2017YFB0503102)。

摘　　要：基于光谱共焦的碱金属气室壁厚测量传感器是通过直接测量光波波长信息来得到透明材料厚度值,是一种非接触式厚度测量传感器。色散物镜是厚度测量传感器的核心部件,色散物镜的线性度和色散范围决定了厚度测量传感器的精度和分辨率。文章介绍了基于光谱共焦的厚度测量传感器的原理,分析了波长信息与轴向色散范围之间的关系,利用ZEMAX光学设计软件对色散物镜进行设计,采用多重结构进行优化。在420~620nm的波长区间内实现0.801mm的轴向色散范围,使用最小二乘法对波长和轴向色散进行线性拟合所得线性度为0.9975。配合0.001nm的高分辨率光谱仪,传感器测量精度可以达到纳米级,满足对碱金属气室壁厚高精度测量的需求。The thickness measurement sensor of alkali metal gas chamber based on spectral confocal is a non-contact thickness measurement sensor,which can obtain the thickness value of transparent material by directly measuring the wavelength information of light wave.The dispersive objective is the core component of the thickness measurement sensor.The linearity and dispersion range of the dispersive objective lens determine the accuracy and resolution of the thickness measurement sensor.The principle of thickness measurement sensor based on spectral confocal is introduced.The relationship between wavelength information and axial dispersion range is analyzed.The dispersive objective lens is designed by using ZEAMX optical design software,and optimizes it with multiple structures.The axial dispersion range of 0.801 mm is achieved in the wavelength range of 420~620 nm.The linear fitting of wavelength and axial dispersion by least square method is 0.9975.With a high resolution spectrometer of 0.001 nm,the measurement accuracy of the sensor can reach nanometer level,which can meet the needs of high-precision measurement of alkali metal gas chamber wall thickness.

关 键 词：光学设计 光谱共焦 色散物镜 线性度 多重结构 

分 类 号：TP394.1[自动化与计算机技术—计算机应用技术] TH691.9[自动化与计算机技术—计算机科学与技术]