We describe a novel strain sensor based on a fiber Bragg grating (FBG) ring resonator. The spectrum of this resonator consists of equally-spaced resonances, exhibiting a frequency splitting proportional to the reflectivity of the intracavity FBG. A strain applied to the FBG causes a shift of the bragg wavelength, and thus a variation of the resonance splitting. The splitting is insensitive to the thermal/strain noise affecting the fiber in the region outside the FBG. The sensitivity and resolution of the sensor are analyzed in detail, showing that a subpicostrain resolution can be easily achieved with an optimized setup.

Date Published: 2 June 2014
PDF: 4 pages
Proc. SPIE 9157, 23rd International Conference on Optical Fibre Sensors, 915706 (2 June 2014); doi: 10.1117/12.2059641

Published in SPIE Proceedings Vol. 9157:
23rd International Conference on Optical Fibre Sensors
José M. López-Higuera; Julian D. C. Jones; Manuel López-Amo; José Luis Santos, Editor(s)