准分布式光纤表面等离子体波传感器  

Quasi-Distributed Optical Fiber Sensor Based on Surface Plasmon Resonance

作　　者：曾捷[1] 梁大开[1] 杜艳[1] 曾振武[1] 

机构地区：[1]南京航空航天大学智能材料与结构航空科技重点实验室,江苏南京210016

出　　处：《中国激光》2007年第2期243-248,共6页Chinese Journal of Lasers

基　　金：国家自然科学基金(60477031);国家自然科学基金重点项目(60535020);江苏省自然科学基金(BK2004128)资助课题

摘　　要：研究了一种基于波分复用原理的准分布式光纤表面等离子体波传感器。应用光波导理论和多层膜反射理论分析了表面等离子体波效应在同一光纤探头中连续被激励的原理及其传感模型。通过数值模拟和相应实验分别考察了蒸镀调制层对表面等离子体波共振（SPR）效果的影响，并在此基础上给出了设计的一般步骤和原则。实验结果表明，蒸镀不同厚度的Ta2O5薄膜将导致表面等离子体波共振光谱发生偏移，且随着膜厚增加而逐渐发生红移；当液体折射率no处于1．333～1．388之间时，蒸镀有Ta2O5薄膜的光纤表面等离子体波传感器波长灵敏度达到2235nm／RIU（Refractive Index Unit）；通过在一支光纤探头上依次加工两个表面等离子体波传感区域，实现了对光波信号的连续调制。A quasi-distributed optical fiber surface plasmon resonance （SPR） sensor based on wavelength division multiplexing is studied. Theory and sensing model of SPR effect excited continuously in the same optical fiber probe are analyzed with light waveguide theory and multi-layer reflection theory. Influences of thickness and type of modulation layer on resonance effect are analyzed quantitatively by utilizing numerical simulation and experiment, and the design approach and principle are also presented. The experiment shows that the variety of thickness of Ta2O5 film will lead to the change of SPR spectrum. Resonance dip shifts gradually to longer wavelength as the thickness of Ta2O5 film becomes thicker. For the range of liquid refractive index from 1.333 to 1. 388, the measuring sensitivity of optical fiber SPR probe coated TazOs film can up to 2235 nm/RIU （Refractive Index Unit）. Broadband light can be modulated continuously by processing two SPR sensing areas within one optical fiber probe.

关 键 词：光纤光学 表面等离子体波共振传感器 准分布式 Ta2O3薄膜 

分 类 号：TN253[电子电信—物理电子学] TP212.14[自动化与计算机技术—检测技术与自动化装置]