Radio-frequency interrogation of a fiber Bragg grating sensor in the configuration of a fiber laser with external cavities

• Published in: Optik (Stuttgart) 2010-11, Vol.121 (22), p.2040-2043
• Main Authors: Vázquez-Sánchez, R.A., Kuzin, E.A., García-Lara, C.M., May-Alarcón, M., Camas-Anzueto, J.L., Righini, Giancarlo C., Miridonov, S.V.
• Format: Article
• Language: English
• Subjects: Bragg gratings; Detection; Exact sciences and technology; Fiber Bragg grating; Fiber laser sensor; Fiber lasers; Fiber optics; Fibers; Fundamental areas of phenomenology (including applications); General equipment and techniques; Holes; Instruments, apparatus, components and techniques common to several branches of physics and astronomy; Interrogation; Lasers; Optical fiber sensor; Optics; Other fiber-optical devices; Physics; Sensors; Sensors (chemical, optical, electrical, movement, gas, etc.); remote sensing; Sensors, gyros; Strain
• ISSN: 0030-4026; 1618-1336
• DOI: 10.1016/j.ijleo.2009.06.006

A fiber laser sensor, which consists of two coupled cavities based on three fiber Bragg gratings (two of them acting as sensing elements) and is interrogated via the longitudinal mode beating frequency, is presented. The two resonant cavities have lengths of 4250 m and 4297 m, respectively. Their beating frequency is of the order of 24 kHz, and its shift as a function of the variation of the period of one (or both) of the sensing gratings, induced by strain or temperature changes, can be measured by a radio-frequency analyzer. The system is suitable for long-distance sensing with high spatial resolution and high sensitivity.