Abstract

Interrogation of fiber Bragg-grating (FBG) structures by laser spectroscopic techniques lias proved in recent years to be very promising for development of highly-sensitive mechanical sensors. In most cases, a strong sensitivity enhancement in strain detection has been obtained relying on laser-frequency modulation techniques to extract wavelength-encoded information on the measurand from the FBG reflection. Particularly, the use of high-finesse fiber-Bragg-grating Fabry- Pérot (FBGFP) cavities as thermo-mechanical gauges lias been demonstrated in a laser-to-cavity lock fashion, achieving a high sensitivity in detecting dynamic strain [1, 2] but also temperature and pressure changes.

© 2007 IEEE