Method for controlling temperature sensitivity of the fiber intermodal sensor and its application in the torsion sensor.

Temperature crosstalk has always been a critical problem for fiber intermodal sensors. In this work, we have proposed a novel method based on the special temperature response of photosensitive fiber to control the temperature sensitivity of the fiber intermodal sensor. The control of temperature sensitivity has been realized via adjusting the proportion of photosensitive fiber to single-mode fiber in the sensing part. The temperature sensitivity as high as -192 pm/°C, and as low as -2.6 pm/°C can be obtained, satisfying the demand in both research and application. The torsion sensor is taken as an example to illustrate feasibility of this method, showing no evident interference in the measurement of torsion parameters. The proposed method outstrips the conventional one by simple structure, facile manufacture, multiple use and low cost, which brings great promise for further employment in laboratory and industry.