Experimental investigation of multicore fiber Bragg grating's crosstalk for curvature sensing

摘要

We experimentally investigated the intercore crosstalk of a multicore fiber (MCF) with Bragg grating inscribed in each core. The purpose is to clarify the effect on the three-dimensional curvature measurement based on a multicore fiber Bragg grating (FBG) and two-photon absorption process in a Si-APD that we have been investigating. The experiment was performed by injecting laser light only in the center core of the MCF and measuring the reflected light from the FBGs in the side cores for the cases that the grating section of the fiber is straight or bent. This measurement was also performed for different wavelength. The measurement results confirmed that the crosstalk was small enough to affect the accuracy of the curvature measurement. We also performed curvature sensing based on the proposed method.