π-phase-shifted FBG for improving static-strain measurement resolution based on triangle-wave laser tuning technique

摘要

In this paper, π-phase-shifted FBG (π-FBG) is used for high-resolution static-strain sensing. A novel laser tuning technique based on triangle-wave voltage driver is proposed to improve wavelength scanning stability of tunable laser. And a static-strain demodulation algorithm based Gauss curve fitting and peak detection is tested. As the reflectance spectrum of π-FBG have high signal-to-noise ratio, a static-strain resolution of 0.83 nε is obtained in a vacuum environment, which shows that the proposed system have a good application prospect for geophysics applications.