大范围光纤布拉格光栅温度传感器增敏实验研究

The Experimental Study of Large Range Enhanced Temperature Sensitivity Concerning Fiber Bragg Grating Temperature Sensor

简要分析了光纤布拉格光栅的温度响应及增敏原理 ,采用特殊耐高温有机聚合物对光纤光栅进行温度增敏封装 ,并通过改进光纤光栅的聚合物封装固化工艺 ,使用某种有机硅导热胶减小有机聚合物与套管材料的粘合度 ,消除了封装过程中由于聚合物材料不均匀收缩引起的光纤光栅反射谱啁啾化 ,实现 2 0～ 180℃范围内光纤光栅传感器对温度高灵敏度测量。实验结果表明 ,聚合物封装光纤光栅传感器温度响应灵敏度在 2 0～ 130℃为0 .0 5nm/℃ ,在 130～ 180℃达到了 0 .2 2nm/℃ ,并在两个区域保持较好的线性与重复性。此结构传感器封装工艺简单 ,易于实现 ,可用于高温恶劣环境下的温度单参量测量。

The temperature response and sensitivity enhancing technology concerning fiber Bragg grating (FBG) is analyzed. A special kind of heat-resistant polymer is used to coat FBG to enhance the temperature sensitivity of FBG sensor. The polymer coating and solidifying process of FBG is improved. A kind of heat-conducted adhesive is used to reduce the friction between tube and polymer, and eliminate the chirp effect of FBG caused by the asymmetric shrinkage of polymer during the package process. The experimental results show that the FBG sensor can measure temperature from 20 ℃ to 180 ℃. The temperature response sensitivity is 0.05 nm/℃ from 20 ℃ to 130 ℃ and 0.22 nm/℃ from 130 ℃ to 180 ℃, respectively, and the response trend line has good linearity in both areas. This kind of sensor is easy to fabricate and can be used for high temperature measurement.