飞秒加工珐珀传感器高温传感非线性理论与实验分析  

Nonlinear theory and experimental analysis of high temperature F-P sensor fabricated by femtosecond lasers

作　　者：邵高杰 陈伟民[1] 苏超乾 邵斌 雷小华[1] 刘显明[1] SHAO GaoJie;CHEN WeiMin;SU Chaoqian;SHAO Bin;LEI XiaoHua;LIU Xianming(Key Laboratory of Optoelectronic Technology & Systems Ministry of Education,College of OptoelectronicEngineering,Chongqing University,Chongqing 400044,China)

机构地区：[1]重庆大学光电工程学院光电技术及系统教育部重点实验室

出　　处：《激光杂志》2018年第12期6-9,共4页Laser Journal

基　　金：重庆市科委基金项目(No.cstc2017zdcy-zdyf0334_1495499677641);国家自然科学基金资助(No.61405019)

摘　　要：利用飞秒激光可以直接在光纤上加工形成本征型光纤法布里-珀罗干涉(IFPI)传感器,此类传感器可以用于高温传感。当温度升高时,光纤的材料特性将发生非线性变化,进而引起传感器的非线性响应,并最终到传感精度的下降。针对此问题,从理论上对IFPI温度传感器的非线性响应进行了深入分析,通过探究温度对光纤热光特性和热膨胀特性的影响,推导出了一阶、二阶、三阶及有效温度灵敏度系数模型。同时,采用飞秒激光制作了腔长为200μm的IFPI温度传感器,并进行了温度实验验证,实验结果表明:在低温区(100℃~200℃)及小范围温度变化区,传感器光程差与温度变化线性关系比较好,温度灵敏度达到3.76nm/℃;在高温及大范围温度变化区(100℃~420℃),光程差与温度变化呈与理论分析一致的非线性关系。为此,采用此类传感器进行高精度温度测量时,需要根据测量范围进行相应的非线性修正。The femtosecond laser can be used to directly fabricated an intrinsic fiber Fabry-Perot interference( IFPI) sensor on an optical fiber. Such a sensor can be used for high temperature sensing. When the temperature rises,the material properties of the fiber will change nonlinearly,which will cause the nonlinear response of the sensor and eventually decrease the sensing accuracy. In view of this problem,this paper theoretically analyzes the nonlinear response of IFPI temperature sensor. By exploring the influence of temperature on the thermo-optic characteristics and thermal expansion characteristics of the fiber,the first-order,second-order,third-order and effective temperature sensitivity are derived. Moreover,the IFPI temperature sensor with cavity length of 200 μm was fabricated by femtosecond laser,and the temperature experiment was carried out. The experimental results show that the optical path difference of the sensor is in the low temperature zone( 100 ℃ ~ 200 ℃) and the small temperature change zone. The linear relationship of temperature change is better,the temperature sensitivity reaches 3.76 nm/℃. In the high temperature and wide temperature range( 100 ℃ ~ 420 ℃),the optical path difference and temperature change are in a nonlinear relationship consistent with the theoretical analysis. For this reason,when using this kind of sensor for high-precision temperature measurement,it is necessary to perform corresponding nonlinear correction according to the measurement range.

关 键 词：高温传感 本征型光纤法珀 非线性 温度测量 飞秒加工 

分 类 号：TN29[电子电信—物理电子学] TN209