Reflective Long-period Fiber Grating Bending Sensor

doi:10.3901/JME.2022.08.054

Abstract

Abstract: The loss peak of the long-period fiber grating transmission spectrum is sensitive to basic physical quantities such as temperature, strain and bending, which has been applied in civil engineering, aerospace and other fields. However, since this type of device mainly uses transmission spectroscopy for detection, the sensing system is complex, which limits the broadening of the application field. Aim to the above problems, a long-period fiber grating sensor based on the structure of the fiber end bonded silicon chip is designed, which can realize the detection of the reflection spectrum of the long-period fiber grating. Studies have shown that the device is sensitive to bending, In addition, because the long-period fiber grating is processed by the femtosecond laser point-by-point direct writing method, the laser modulation area is asymmetrical due to the focus of the objective lens and the self-focusing of the fiber. The sense has obvious directionality.

Key words: long period fiber grating, femtosecond laser, bending sensor, reflection spectrum

CLC Number:

TG156

SUN Xiaoyan, ZHANG Wei, LÜ Weiwei, ZHANG Limu, HU Youwang. Reflective Long-period Fiber Grating Bending Sensor[J]. Journal of Mechanical Engineering, 2022, 58(8): 54-62.

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