改善波形并增敏的光纤光栅温度传感技术

选用热膨胀系数较大的聚合物和某种偶联材料,采用特殊工艺用其对裸光纤光栅进行封装,消除了封装过程中所带来的光纤光栅啁啾现象,极大地改善了光纤光栅反射波的波形,提高了封装测试过程的重复性,为波长解调解决了一大难题.在30.6℃~120℃范围内,测量过程中波形很好并几乎不变,温度灵敏度为0.1173 nm/℃,温度分辨率为<0.43℃,比裸光纤光栅增加了11倍;平均灵敏度增敏倍数γ′=10.34,与理论计算灵敏度增敏倍数γ=10.76符合得比较好.聚合物封装光纤光栅的温度响应曲线具有很好的线性.

A Novel Technique of Temperature Sensitivity Enhancement and Reflection Spectrum Improvement of Fiber Bragg Gratings

A novel fiber grating temperature sensing technique and its experimental result is reported,which eliminates the chirped effects of polymer-packaged,improves the reflection spectrum of FBG and the technique of repeated packaged by using a kind of polymer-packaged with biggish thermal expansion coefficient and a special coupling agent. The experimental result indicates that ,within 30.6℃~120℃ ,the temperature sensitivity is 0.1173 nm/℃ and the resolution temperature measurement is <0.43℃,which are 11 times higher than that of the bare FBG and the most important advantage is that the reflection spectrum remains same in the whole test.The average temperature sensitivity multiple of polymer-packaged fiber Bragg gratings is γ′=10.34,which matches the theoretical multiple γ=10.76 well. The linearity of the temperature response curves is 0.9983.