Experimental Study of Fiber-Optic Temperature Sensor Based on Dual FSIs  

作　　者：Xiaotong XU Xuefang ZHOU Guowei YANG Meihua BI Mengmeng XU Yuansheng XU 

机构地区：[1]School of Communication Engineering,Hangzhou Dianzi University,Hangzhou 310018,China [2]Department of Emergency,Affiliated Hangzhou First People’s Hospital,School of Medicine,Westlake University,Hangzhou 310006,China

出　　处：《Photonic Sensors》2025年第2期119-131,共13页光子传感器(英文版)

基　　金：supported by the Primary Research and Development Plan of Zhejiang Province,China(Grant No.2023C03014);the Key Research and Development Program of Zhejiang Province,China(Grant No.2022C03037).

摘　　要：To improve the sensitivity measurement of temperature sensors,a fiber optic temperature sensor structure based on the harmonic Vernier effect with two parallel fiber Sagnac interferometers(FSIs)is designed,and theoretical analysis and experimental testing are conducted.The FSI consisting of two polarization maintaining fibers(PMFs)with lengths of 13.62 m and 15.05 m respectively is used to achieve the basic Vernier effect.Then by changing the length of one PMF to approximately i times that of the others,the FSI composed of two PMFs of 7.1 m and 15.05 m is used to achieve the first-order harmonic Vernier effect.Afterward,temperature sensing tests are conducted to observe the wavelength drift during temperature changes and ultimately achieve high sensitivity.The experimental results show that the temperature sensitivity of the sensor based on the first-order harmonic Vernier effect is-28.89 nm/,which℃is 17.09 times that of a single FSI structure(-1.69 nm/)and 1.84 times that of the sensitivity generated by the structure based on the℃basic Vernier effect(-15.69 nm/).The experimental results℃are consistent with the theoretical analysis.The structure proposed in this paper achieves drift measurement of 0.1℃℃variation based on 1 drift,making the fiber optic temperature sensor applicable to related fields that requir e high precision temperature.The proposed temperature sensor has the simple structure,low production cost,high sensitivity,and broad application prospects.

关 键 词：Fiber optic temperature sensor fiber optic Saganc interferometer harmonic Vernier effect 

分 类 号：TN253[电子电信—物理电子学]