应用于梯度折射率测量的长波红外干涉仪  

Long wave infrared interferometer applied to gradient refractive index measurement

作　　者：张祐诚 郑东晖[1] 黄一飞 李晶晶 陈磊[1] ZHANG Youcheng;ZHENG Donghui;HUANG Yifei;LI Jingjing;CHEN Lei(School of Electronic and Optical Engineering,Nanjing University of Science and Technology,Nanjing2100941,China)

机构地区：[1]南京理工大学电子工程与光电技术学院,江苏南京210094

出　　处：《光学技术》2025年第2期169-174,共6页Optical Technique

基　　金：中央高校基本科研业务费专项资金(30923010934);国家自然科学基金(62005122);江苏省自然科学基金(BK20200458)。

摘　　要：红外梯度折射率材料折射率大且折射率变化大,导致干涉条纹密度大且密度变化大。为了精确测量红外梯度折射率材料,研究了一种λ=10.6μm红外马赫-曾德尔干涉仪,设计了一种变焦、定焦同步成像方案,解决了材料大梯度分布情况下条纹过密导致的难以测量难题,通过测量红外梯度折射率材料的透射波前从而得到其折射率分布。利用该干涉仪测量厚度为2mm的轴向梯度折射率样品和厚度为9mm的径向梯度折射率样品,得到两样品折射率变化分别为0.305和0.053。使用该干涉仪测量红外梯度折射率样品,样品折射率变化陡度最大为0.035。为了验证该干涉仪的测量精度,测量厚度为10mm的硅片的透射波前,结果表示折射率测量误差在10^(-5)量级。The infrared gradient refractive index material has a large refractive index and a large refractive index variation, resulting in a high density and density variation of interference fringes. In order to accurately measure the infrared gradient refractive index material, a λ=10.6 μm infrared Mach Zehnder interferometer was studied, and a zoom and fixed focus synchronous imaging scheme was designed to solve the difficult measurement problem caused by dense stripes in the case of large gradient distribution of materials. The refractive index distribution of infrared gradient refractive index materials was obtained by measuring the transmitted wavefront. Using this interferometer, the axial gradient refractive index sample with a thickness of 2mm and the radial gradient refractive index sample with a thickness of 9mm were measured, and the refractive index changes of the two samples were obtained to be 0.305 and 0.053, respectively. Using this interferometer to measure the infrared gradient refractive index sample, the maximum steepness of the sample's refractive index change is 0.035. To verify the measurement accuracy of the interferometer, the transmitted wavefront of a 10mm thick silicon wafer was measured, and the results showed that the refractive index measurement error was in the range of 10^(-5).

关 键 词：干涉测量 红外干涉仪 马赫-曾德尔干涉仪 折射率梯度 

分 类 号：TH744.3[机械工程—光学工程]