Theoretical and Experimental Research on Temperature Sensing Characteristics of PANDA Fiber Gratings

The temperature sensing model of PANDA fiber grating is built using the finite element method. The interior stress distributions of PANDA fiber caused by temperature changing are studied, together with the influence of fiber structure on temperature sensing characteristics. Both the theoretical and experimental results show that the temperature sensing coefficients of two reflective peaks and peak separation are linear with the square of the ratio of radius to distance of Stress Applied Zone(SAZ) and the temperature response ability of fast axis is stronger than that of slow axis.