基于梯形介质光栅金属薄膜结构的折射率传感器  

Refractive Index Sensor Based on Trapezoidal Dielectric Grating and Metallic Film Structure

作　　者：刘啸[1] 王正岭[1] Liu Xiao;Wang Zhengling(Faculty of Science,Jiangsu University,Zhenjiang,Jiangsu 212013,China)

机构地区：[1]江苏大学理学院,江苏镇江212013

出　　处：《激光与光电子学进展》2019年第7期264-268,共5页Laser & Optoelectronics Progress

基　　金：江苏省自然科学基金(BK20161342);江苏省"六大人才高峰"高层次人才项目(GDZB-018);江苏省高校自然科学研究重大基金(15KJA140001)

摘　　要：提出了一种基于梯形介质光栅金属薄膜结构的折射率传感器。利用有限元方法,研究了不同光栅厚度、梯形参数以及不同折射率下待分析液体的反射谱线。对传感器结构参数进行优化,得到了传感器的角灵敏度。考虑由反射谱线共振峰的对称移动导致的角灵敏度加倍效应,当待分析液体折射率从1.33变化到1.34时,传感器角灵敏度可达845.23(°)/RIU(RIU为折射率单位);从1.34变化到1.35时,传感器角灵敏度可达1283.14(°)/RIU,并且该传感器具有更宽折射率范围的检测应用。梯形参数对传感器的角灵敏度起着决定性的作用,具有最大灵敏度的传感器结构能形成对比度最大的电场分布驻波结构。A refractive index sensor based on the trapezoidal dielectric grating and the metallic film structure is proposed.The reflectivity of liquid to be analyzed is studied by the finite element method with different grating thicknesses,trapezoidal parameters and refractive indices.The angular sensitivity of the sensor is derived by optimizing the structure parameters.In consideration of the doubling effect of the angular sensitivity caused by the symmetrical movement of reflection resonance peaks,the angular sensitivity can reach 845.23(°)/RIU as the refractive index of liquid to be analyzed is changing from 1.33 to 1.34,and 1283.14(°)/RIU as the refractive index is changing from 1.34 to 1.35.The sensor has detection applications with a wide range of refractive index.The trapezoidal parameter plays a key role in the angular sensitivity of the sensor.A standing wave structure of the electric field distribution with the largest contrast corresponds to the highest sensitivity of the sensor structure.

关 键 词：表面光学 介质光栅 金属薄膜 折射率传感器 加倍效应 驻波结构 

分 类 号：O436[机械工程—光学工程]