用单一倾斜光纤光栅实现曲率和温度的同时测量

Simultaneous Measurement of Bending-Curvature and Temperature Using Single Tilted Fiber Bragg Grating

基于单个倾斜光纤光栅(TFBG)提出了一种实现双参量曲率和温度同时测量的方法。研究发现,当弯曲方向与光栅栅面成一定角度时,倾斜光纤光栅的纤芯模谐振波长对弯曲不敏感而随外界温度变化线性漂移;低阶包层模谐振峰透射功率随曲率的增加而线性减小且对温度变化不敏感。由此特性提出了用单个倾斜光纤光栅的纤芯模谐振波长和低阶包层模谐振峰透射功率,分别实现对两个参量温度和曲率进行同时独立测量的传感器设计方案,该方法有望解决光纤光栅在测量中存在的温度和弯曲之间的交叉敏感问题。

A novel application of tilted fiber Bragg gratings （TFBG） for measuring the bending curvature and temperature simultaneously and independently is reported. The coupling-strength variations of the lower cladding modes provide information on the curvature as they are responsive to curvature changes but unresponsive to temperature, whereas the wavelength shifts of the core-mode peaks facilitate measurement of temperature because the core mode is unresponsive to curvature changes but responsive to temperature, Therefore, those features allow using a single TFBG for simultaneous measurements of temperature and bending curvature. The proposed scheme can be used to solve temperature-cross problem in the real applications.