Temperature Sensor Based on Fiber Bragg Grating Embedded in SNS Fiber Structure

TN253; A novel fiber temperature sensor based on multimode interference theory is proposed and experimentally demonstrated .The sensing head is formed by a fiber bragg grating (FBG) connected with single-mode-no core-sin-gle-mode fiber(SNS) fiber structure which consists of two sections of single mode fiber and no-core fiber .Using such a structure ,not only the reflective measurement can be realized ,but also the need for a gold-plated film can be avoided at the end of the fiber to enhance the reflected light signal .More importantly ,the sensitivity is in-creased by 4 times as compared with the conventional FBG temperature sensor according to the experimental re-sults ,and it also provides the development space for multi-parameters monitoring .