Temperature-independent bending sensor with tilted fiber Bragg grating interacting with multimode fiber

Abstract: A new type fiber bending sensor based on a tilted fiber Bragg grating (TFBG) interacting with a multimode fiber (MMF) is presented. The sensing head is formed by insertion of a small section of MMF between a single-mode fiber (SMF) and the TFBG. The average reflective power in the cladding modes decreases with the increase of curvature. The measurement range of the curvature from 0 to 2.5m−1 with a measurement sensitivity of −802.4nW/m−1 is achieved. The proposed sensor is also proved as temperature-independent from the experimental investigation. [Copyright &y& Elsevier]