High Temperature Sensor Based on Regenerative Fiber Bragg Grating

In this paper, two kinds of gratings are used to represent seed gratings of different intensities, which are obtained by conventional writing (R ≥ 70%) and saturation writing (R ≥ 99%) on low-cost SMF-28 fibers respectively. After same high-temperature annealing process, the performance of the grating with saturation writing is more stable, and it is suitable for making a high temperature sensor. By means of calibration tests, the wavelength of the regenerative grating drifted by 15.3 nm during the temperature rise to 1100 ℃, and its full-scale temperature resolution was 0.073 ℃/pm. In combination with the engineering needs, the high temperature resistant capillary ceramic tube and corundum tube are used to encapsulate the grating; therefore, the high temperature resistance of the regenerative fiber grating is used to fabricate the ceramic packaged fiber grating high temperature sensor. Sensing targets with the temperature range from 0 to 1000 ℃ and an accuracy of 1 ℃ are implemented ultimately.