Performance investigation on pressure sensing from fiber Bragg grating loop ring-down cavity

Abstract

The theoretical description and experimental demonstration for pressure sensing characterized over the spectrum shift of FBG and exponential property are reported, which are investigated through the system of an optical fiber loop ring-down cavity (FLRDC) inserted a fiber Bragg grating (FBG). The mathematical models and simulations of FLRDC-FBG are established to investigate the exponential equation between pulses’ peak intensities and time delays with different pressure perturbations, which agrees well with experimental results. Meanwhile, the experimental performances of pressure applied to the FBG are analyzed by measuring the central wavelength and ring-down time from FLRDC-FBG. The pressure sensing with FLRDC-FBG shows the perfect repeatability, stability and high sensitivity. The measurement sensitivity of the proposed FLRDC-FBG achieves 0.00981/(μs ⋅ kPa) by discussing the relationship between ring-down time and pressure. The relationship between pressure and central wavelength indicates the sensitivity of 0.65 pm/kPa. The experimental results not only exhibit the good performances to the proposed pressure sensing of FLRDC-FBG but also demonstrate its usefulness for pressure measurement.