中国激光, 2019, 46 (8): 0804004, 网络出版: 2019-08-13
基于短相干技术的光学平板折射率测量方法 下载: 1003次
Measuring Refractive Index of Transparent Plate by Low-Coherent Interference
测量 迈克耳孙干涉 短相干 迭代算法 折射率测量 measurement Michelson interference low-coherent interference iterative algorithm measurement of refractive index
摘要
为测量光学平板玻璃折射率,提出一种改进的基于迈克耳孙原理的折射率测量方法。利用短相干光源的空间相干性,结合距离测量工具,可准确获得光学间隔间的距离。分别测量放入样品前后以及按照一定角度旋转样品后的光学距离,同时利用折射定律,可以计算得到光学平板玻璃的折射率。提出了一种迭代计算方法,不需要直接求解一元四次方程,实现了折射率的快速计算。分析距离和角度测量误差以及样品平行度引入的误差可知,本文方法折射率测量误差优于5×10
-5。与V棱镜折射率测量方法进行比较,结果验证了本文方法的正确性。
Abstract
In order to measure the refractive index of transparent plate, an improved method based on the Michelson principle is proposed. Using the spatial coherence of low-coherent light sources and distance measurement tools, the distance between optical intervals can be accurately obtained. The optical distances before and after placing the sample and after rotating the sample at a certain angle are measured, respectively. Hence, the refractive index of the optical glass plate can be calculated by using the law of refraction. An iterative algorithm is proposed to avoid directly solving the quaternary equation of one variable and realize fast calculation of the refractive index. By analyzing the measurement errors of distance, angle, and parallelism of the sample, it is found that the refractive index measurement error of the proposed method is better than 5×10
-5. The comparison result with the V-prism refractive index measurement method verifies the correctness of the proposed method.
高波, 李强, 刘昂, 柴立群. 基于短相干技术的光学平板折射率测量方法[J]. 中国激光, 2019, 46(8): 0804004. Bo Gao, Qiang Li, Ang Liu, Liqun Chai. Measuring Refractive Index of Transparent Plate by Low-Coherent Interference[J]. Chinese Journal of Lasers, 2019, 46(8): 0804004.