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

摘要

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-single-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 increased by 4 times as compared with the conventional FBG temperature sensor according to the experimental results,and it also provides the development space for multi-parameters monitoring.