Gain in hydrostatic pressure sensitivity of fiber bragg grating packaged by polymer and metal cylinder

Abstract

A fiber Bragg grating pressure sensor was designed and packaged by polymer and metal cylinder. In order to predict the hydrostatic pressure sensitivity, the relationship among the hydrostatic pressure sensitivity coefficient and the elasto-optic coefficient of bare fiber, Young's modulus, Poisson' ratio of the packaging polymer and geometry parameter was established. The theoretical and experimental pressure sensitivity coefficients are 5.37 times 10-3/MPa and 3.80 times 10 -3/MPa, which are 2781 and 1970 times of that of the bare fiber Bragg grating respectively. The experimental results agree to the calculated values