The reflection characteristics of thermal Regenerated fiber Bragg grating

The thermal regenerated grating was prepared from an ordinary single-mode fiber Bragg grating though high temperature annealing process in this paper. And the temperature characteristics and spectral properties of the thermal regenerated grating were investigated. The results show that the erasing temperature of the initial seed gratings of FBG is about 970 degrees C and the regenerating temperature of the FBG is about 990 degrees C. The wavelength of the thermal regenerated gratings (RFBG) exhibit excellent linear relationship with the temperature change, and the temperature sensitivity coefficient of the RFBG can get to 0.01564 nm/ degrees C. The high-temperature sensing experiments indicate that the RFBG has a good repeatability and the optical powers of the reflection spectrum remains stable during the heating and cooling process.