Bending Vector Sensor Based on the Multimode-2-Core-Multimode Fiber Structure

A novel bending vector sensor formed by splicing 2-core fiber (2CF) between two segments of multimode fibers (MMFs) was proposed and fabricated, in which the MMFs serve as the mode splitting and coupling. Moreover, the 2CF used in the experiment was designed and fabricated in our labs, and the external core with a larger diameter would be provided with a higher bending sensitivity. Besides, the bending responses of the sensor are directionally sensitive due to the asymmetric structure of the 2CF. As a result, along with the implementation of the conformation experiments on the bending and temperature sensor property, and a good agreement has been achieved. The proposed sensor possesses many advantages, such as being inexpensive, compact, and robust.