Temperature-independent refractive index measurement based on Fabry-Perot fiber tip sensor modulated by Fresnel reflection  

作　　者：马玥 乔学光 郭团 王若晖 张菁 翁银燕 荣强周 忽满利 冯忠耀 

机构地区：[1]Department of Physics,Northwest University [2]Institute of Photonics Technology,Jinan University,Guangzhou 510632,China

出　　处：《Chinese Optics Letters》2012年第5期19-22,共4页中国光学快报（英文版）

基　　金：supported by the National Natural Science Foundation of China (Nos. 60727004 and 61077060);the National "863" Program of China (Nos.2007AA03Z413 and 2009AA06Z203);the Ministry of Education Project of Science and Technology Innovation(No. Z08119);the Ministry of Science and Technology Project of International Cooperation (No. 2008CR1063);the Shaanxi Province Project of Science and Technology Innovation (Nos. 2009ZKC01-19 and 2008ZDGC-14);the Guangdong Nature Science Foundation (No.S2011010001631);the Fundamental Research Funds for the Central Universities of China (No. 11611601)

摘　　要：A simple fiber tip sensor for refractive index （RI） measurement based on Fabry-Perot （FP） interference modulated by Fresnel reflection is proposed and demonstrated. The sensor head consists of an etching- induced micro air gap near the tip of a single-mode fiber. The microgap and the fiber tip function as two reflectors to form a FP cavity. The external RI can be unambiguously measured by monitoring the fringe contrast of the interference pattern from the reflection spectrum. The experimental results show that the proposed sensor achieves temperature-independent RI measurement with good linear response. The proposed sensor achieves a high RI resolution of up to 3.4× 10^-5 and has advantages of low cost and easy fabrication.A simple fiber tip sensor for refractive index （RI） measurement based on Fabry-Perot （FP） interference modulated by Fresnel reflection is proposed and demonstrated. The sensor head consists of an etching- induced micro air gap near the tip of a single-mode fiber. The microgap and the fiber tip function as two reflectors to form a FP cavity. The external RI can be unambiguously measured by monitoring the fringe contrast of the interference pattern from the reflection spectrum. The experimental results show that the proposed sensor achieves temperature-independent RI measurement with good linear response. The proposed sensor achieves a high RI resolution of up to 3.4× 10^-5 and has advantages of low cost and easy fabrication.

关 键 词：FABRY Perot interferometers Fibers Refractive index Single mode fibers 

分 类 号：TP212[自动化与计算机技术—检测技术与自动化装置]