Localized strain sensing with fiber Bragg-grating ring cavities
Authors: Campanella C. E., Giorgini A., Avino S., Malara P., Zullo R., Gagliardi G., De Natale P.
Autors Affiliation: Consiglio Nazionale delle Ricerche, Istituto di Tecnologie Industriali e Automazione (ITIA) Via Paolo Lembo 38F – 70124 Bari, Italy; Consiglio Nazionale delle Ricerche, Istituto Nazionale di Ottica (INO), via Campi Flegrei, 34 – Comprensorio A. Olivetti, 80078 Pozzuoli (Naples), Italy
Abstract: We report the theoretical description and the experimental demonstration of an optical resonator formed by inserting a Fiber Bragg Grating (FBG) in a closed fiber loop. The spectral characteristics of such a resonator strongly depend on the reflectivity of the FBG. In the wavelength region where the FBG reflectivity R is negligible, the system behaves like a conventional ring resonator. On the other hand, when R is not vanishing, a split-mode structure can be observed, associated to the degeneracy removal of two counterpropagating resonant modes. The magnitude of the mode splitting can be used to sense small variations of the FBG physical parameters, such as length, temperature or group index. An example of strain sensing with this setup is reported, showing that the mode splitting is sensitive to a mechanical strain applied to the FBG, while it is almost insensitive to a strain applied to any other point of the resonator. This peculiar feature allows to perform cavity-enhanced, local strain measurements with a reduced sensitivity to environmental perturbations, which represents an important improvement in the framework of the fiber-optic sensors. (C)2013 Optical Society of America
Journal/Review: OPTICS EXPRESS
Volume: 21 (24) Pages from: 29435 to: 29441
More Information: This work was funded by Italian Ministry of Education and Research (MIUR) in the framework of PON01_01209 \”BACKOP\” project. We thank G. Notariale for technical assistance.KeyWords: Fibers; Optical resonators; Reflection, Counterpropagating; Environmental perturbations; Experimental demonstrations; Mechanical strain; Physical parameters; Reduced sensitivity; Spectral characteristics; Wavelength regions, Fiber Bragg gratings, algorithm; article; equipment; equipment failure; fiber optics; materials testing; mechanical stress; refractometry; surface plasmon resonance; transducer; Young modulus, Algorithms; Elastic Modulus; Equipment Failure Analysis; Fiber Optic Technology; Materials Testing; Refractometry; Stress, Mechanical; Surface Plasmon Resonance; TransducersDOI: 10.1364/OE.21.029435Citations: 33data from “WEB OF SCIENCE” (of Thomson Reuters) are update at: 2020-11-29References taken from IsiWeb of Knowledge: (subscribers only)Connecting to view paper tab on IsiWeb: Click hereConnecting to view citations from IsiWeb: Click here