光纤Bragg光栅温度和应变的灵敏度分析及应用探讨

Analysis of sensitivity of optical fiber Bragg gratings and research on its application

本文从Ｂｒａｇｇ 光栅方程出发，推导出了光纤Ｂｒａｇｇ 光栅传感器的温度和应变一阶和二阶灵敏度以及温度－ 应变交叉灵敏度的计算公式，结合实际数据进行了计算，估计了忽略二阶和交叉灵敏度可能带来的误差。并指出改变Ｂｒａｇｇ 光栅的封装形式可以提高其温度灵敏度，用此方法同时测量温度和应变时，可以降低灵敏度矩阵的条件数。

From equation of Bragg gratings,the formula of the first and the second order sensitivities of strain and temperature and the cross sensitivity are obtained.With the experimental date,the errors induced by the second order sensitivities and cross sensitivity are calculated and some conclusions are obtained.By sticking the FBG on aluminum firmly,the temperature sensitivity can be improved.Using this method to measure strain and temperature simultaneously,the condition number of the matrix of sensitivities can be dropped from 161 to 43,so the accuracy of the sensor can be improved.