级联式光纤FPI-SPR液体热光系数传感器  

Cascaded Fiber-Optic FPI-SPR Liquid Thermo-Optic Coefficient Sensor

作　　者：金澳博 常建华[1,2] 胡子怡 徐遥 陈鸣 Jin Aobo;Chang Jianhua;Hu Ziyi;Xu Yao;Chen Ming(School of Electronic and Information Engineering,Nanjing University of Information Science&Technology,Nanjing 210044,Jiangsu,China;Collaborative Innovation Center of Atmospheric Environment and Equipment Technology,Nanjing University of Information Science&Technology,Nanjing 210044,Jiangsu,China)

机构地区：[1]南京信息工程大学电子与信息工程学院,江苏南京210044 [2]南京信息工程大学江苏省大气环境与装备技术协同创新中心,江苏南京210044

出　　处：《中国激光》2024年第17期269-277,共9页Chinese Journal of Lasers

基　　金：国家自然科学基金(62175114,62375137)。

摘　　要：设计了一种基于光纤法布里-珀罗干涉(FPI)和表面等离子体共振(SPR)效应的高精度液体热光系数传感器。该传感器利用端面固化了聚二甲基硅氧烷(PDMS)的单模光纤(SMF)和无芯光纤(NCF)在毛细硅管中构造了PDMS-Air-PDMS非本征FPI结构,并在NCF侧面镀银纳米膜构造SPR传感单元,实现了温度和折射率的高灵敏度测量。通过FPI对SPR传感单元进行了温度补偿,消除了交叉干扰。实验结果表明,传感器在1.333~1.371折射率范围内的灵敏度达到2913.68 nm/RIU,在20~80℃温度范围内灵敏度达到597 pm/℃,无水乙醇的热光系数测量误差仅为0.82%。该传感器具有高精确度、制作简单、集成度高、无串扰和无交叉敏感等优点,在生物医学和生物化学领域中有着广阔的应用前景。Objective The refractive index(RI)of a material that varies with temperature is quantified as the thermal-optic coefficient(TOC),which is crucial for characterizing materials and performing chemical and biochemical analyses.The key challenge in TOC measurement is the simultaneous measurement of changes in temperature and RI.Traditional TOC measurement systems involve the separate detection of temperature and RI changes,resulting in inconsistent spatial and temporal data.This leads to measurement errors and low accuracy in the TOC due to nonuniform thermal conduction and convection in materials.Fiber-optic sensors have gained significant attention and research interest owing to their ability to measure multiple parameters,such as corrosion resistance,and their compact size,high sensitivity,and strong immunity to electromagnetic interference.With the increasing applications of fiber optic sensing,various temperature-and RI-sensitive fiber optic sensors have been developed to measure the TOC of liquid materials,including sensors based on surface plasmon resonance(SPR),interference,and fiber Bragg grating.However,achieving high-precision measurements remains challenging because of issues such as crosstalk and cross-sensitivity.A cascaded Fabry-Perot interferometer(FPI)-SPR all-fiber liquid TOC sensor is proposed to address these challenges.This sensor uses a single-mode fiber(SMF)with one end coated with polydimethylsiloxane(PDMS)and a no-core fiber(NCF)embedded in a capillary to construct a PDMS-air-PDMS nonintrinsic FPI structure.In addition,a silver-coated nanofilm on the side of the NCF forms an SPR sensing unit for high-sensitivity temperature and RI measurements.The FPI compensates for the temperature in the SPR sensing unit,eliminating the cross-sensitivity of temperature and RI in SPR.Methods First,two segments of multimode and single-mode optical fibers are prepared.One segment of the multimode fiber is fused with a 15 mm long coreless fiber using a fiber-optic fusion splicer.Subsequently,the SMF and fused c

关 键 词：传感器 光纤传感器 法布里-珀罗干涉仪 表面等离子体共振 折射率 温度 热光系数 

分 类 号：TP212[自动化与计算机技术—检测技术与自动化装置]