基于白光扫描干涉法的光纤折射率分布的测量  

Measurement of Optical Fiber Refractive Index Distribution Based on White Light Scanning Interferometry

作　　者：李敏 宋五洲 湛位 吴荣耀 邱锦华 LI Min;SONG Wuzhou;ZHAN Wei;WU Rongyao;QIU Jinhua(Center for Joining and Electronic Packaging,School of Materials Science and Engineering,Huazhong University of Science and Technology,Wuhan 430074,China)

机构地区：[1]华中科技大学材料科学与工程学院连接与电子封装中心,武汉430074

出　　处：《光子学报》2021年第4期39-45,共7页Acta Photonica Sinica

基　　金：华中科技大学人才引进基金(No.3004110112)。

摘　　要：提出了一种光纤折射率分布的测量方法,采用白光扫描干涉技术,并在参考镜上构造与光纤样品相同的结构来克服白光相干长度短的限制,优化了光路,提高了干涉条纹间的对比度。采用与白光干涉信号的包络线呈高斯分布的Morlet小波作为小波变换的母小波进行拟合处理,得到光纤与已知折射率的匹配液之间的相对高度。通过计算获得光纤的折射率分布,并对获得的数据采用光纤折射率分布的经典函数进行拟合,得到多模光纤和单模光纤的决定系数分别为0.997 2和0.996 4。最后将实验获得的结果与官方参数进行比较,误差为0.01%,表明该种方法测量的精度较高,完全可以用来测量光纤的折射率。A method for measuring the refractive index distribution of optical fibers is presented,which uses the white light scanning interference technology and builds the same structure on the reference mirror as the optical fiber sample to overcome the limitation of the short white light coherence length,optimizes the optical path and improves the contrast between the interference fringes.For white light interference signals,Morlet wavelet which has Gaussian distribution like envelope of white light interference fringes is used as the mother wavelet of wavelet transform for fitting processing,and the relative height between the fiber and the matching fluid with known refractive index is obtained.The refractive index distribution of optical fiber can be obtained by calculation,and fitting the obtained data with the classical function of the refractive index distribution of the fiber core,the coefficients of determination of the multi-mode fiber and singlemode fiber are 0.9972 and 0.9964 respectively.Finally,the experimental results are compared with the official parameters,and the error is 0.01%,which shows that this method has a high precision and can be used to measure the refractive index of optical fiber.

关 键 词：干涉仪 扫描显微镜 折射率剖面 光纤测量 条纹分析 

分 类 号：TN253[电子电信—物理电子学]