提出了一种能够测量高温的光纤布拉格光栅(FBG)传感器结构。利用线膨胀系数和长度均不同的两种金属细杆和光纤布拉格光栅设计而成的传感头,能够将被测温度转化为光栅的应变,解调由应变引起的光栅波长漂移,即可得知待测的温度。目前在实验室实现了500 ℃的动态范围和1 ℃的温度分辨率,实验结果与理论分析一致。

A simply and low-cost fiber Bragg grating (FBG) high temperature sensor is introduced in this paper. The sensing head is comprised of one fiber Bragg grating and two metal strips with different length and different coefficients of thermal-expansion (CTE). The sensing head can transform the temperature to be measured into the strain of FBG. It can be known the temperature by interrogating the wavelength of the FBG that induced by the strain. A dynamic range of 500 ℃ and a resolution of 1 ℃ have been realized in experiments. The experiment results agree well with the theoretical analysis.