Optical fibre sensor

The utility model relates to an optical fiber temperature sensor, which is a measuring device for measuring various temperatures. The optical fiber temperature sensor adopts a macromolecule temperature sensitive material to coat at the outside of two optical fibers which are welded together, and the light is made to be input the reflecting face from one optical fiber and to be output from the other optical fiber. Because the refractivity of the novel temperature sensitive material changes under the temperature influence, the output light power and the temperature are in functional relation. The optical fiber temperature sensor has the characteristics of simple structure, small volume, light weight, convenient use, high sensitivity, good repeatability, strong anti-interference capability and explosion protection.