基于并联回音壁结构的光纤曲率传感器  

An optical fiber curvature sensor based on the parallel whispering gallery mode structure

作　　者：刘睿洋 康娟 徐婷 汤毅 赵春柳 李裔 LIU Ruiyang;KANG Juan;XU Ting;TANG Yi;ZHAO Chunliu;LI Yi(College of Optical and Electronic Technology,China Jiliang University,Hangzhou 310018,China)

机构地区：[1]中国计量大学光学与电子科技学院,浙江杭州310018

出　　处：《中国计量大学学报》2022年第4期527-532,共6页Journal of China University of Metrology

基　　金：浙江省医疗电子与数字健康重点实验室资助项目(No.MEDH202209);中国计量大学科研标志性发展专项项目(No.2021YW75)。

摘　　要：目的:提出了一种基于并联回音壁结构(parallel whispering gallery mode,PWGM)的光纤传感器用于曲率测量。方法:将单模光纤弯曲成“8”字形得到PWGM结构,再用柔韧性强、耐热特性好的硅酮胶对传感器进行封装。当该PWGM传感器由于弯曲发生形变时,其纤芯与包层的有效折射率差值随之发生变化,导致输出干涉光谱发生漂移。结果:实验选取两个特征波谷作为监测对象分别进行曲率和温度测量,结果表明,在0~1.29 m^(-1)的曲率范围内,PWGM传感器正向弯曲时曲率灵敏度分别为5.73 nm/m^(-1)和6.15 nm/m^(-1),负向弯曲时曲率灵敏度分别为-3.64 nm/m^(-1)和-3.66 nm/m^(-1);在30~55℃的温度范围内,PWGM传感器的温度灵敏度分别为-0.83 nm/℃和-0.92 nm/℃。此外,通过构建曲率和温度的测量矩阵消除了温度的交叉影响。结论:提出的曲率传感器在测量曲率大小的同时还能够对弯曲方向作出判断,这在硅片翘曲、结构变形等领域具有良好的应用前景。Aims:A fiber optic sensor based on the parallel whispering gallery mode(PWGM)was proposed to curvature measurement.Methods:A single-mode optical fiber was bent into an 8-shaped to obtain the PWGM structure.Then the structure was packaged by silicone glue with strong flexibility and good heat resistance.When the PWGM sensor was deformed due to bending,the effective refractive index difference between the core and the cladding changed accordingly,which eventually led to a shift of the output interference spectrum.Results:In the experiment,two characteristic troughs were selected as the monitoring objects in curvature and temperature measurements.Results showed that in the range of 0~1.29 m^(-1),the curvature sensitivities of the troughs were 5.73 nm/m^(-1)and 6.15 nm/m^(-1)when the sensor was bent in the positive direction;and the sensitivities in the negative direction were-3.64 nm/m^(-1)and-3.66 nm/m^(-1).In the range of 30~55℃,the temperature sensitivities of the troughs were-0.83 nm/℃and-0.92 nm/℃.In addition,the cross influence of temperature was eliminated by constructing the curvature and temperature measurement matrix.Conclusions:The proposed curvature sensor can measure the curvature and judge the bending direction.It has a good application prospect of silicon wafer warping,structural deformation and other fields.

关 键 词：光纤传感 曲率传感器 回音壁模式 硅酮胶封装 

分 类 号：TN253[电子电信—物理电子学]