Cladding mode resonance of special optical fiber for bending sensor with temperature insensitivity

Abstract

In this paper, we fabricated and demonstrated a temperature-insensitive fiber bending sensor based on a special optical fiber with cladding mode resonance. The special fiber, with pure silica core and a fluorine-codoped inner cladding, fabricated by using conventional MCVD technique exhibited strong cladding mode resonance. The bend curvature dependence of resonant spectrum was investigated with high sensitivity to be -10.15nm•m^-1 and was found to possess an insensitivity to temperature. The proposed special fiber bending sensor is simple and low cost.