Directional bending sensor based on spatially arrayed long period gratings in multicore fiber

摘要

Spatially arrayed long period gratings (LPGs) are inscribed in a multicore fiber by CO₂ laser. The LPGs in the center core and one outer core exhibit different responses to bending and temperature. The directional bending sensor based on the LPGs has large sensitivity even for ultra-low curvature values ranging from 0 to 0.359 m-1.