
Intracavity interrogation of an array of fiber Bragg gratings
Author(s) -
Walter Margulis,
Robert Lindberg,
Fredrik Laurell,
Gunnar Hedin
Publication year - 2020
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.414094
Subject(s) - fiber bragg grating , optics , materials science , laser linewidth , interrogation , phosfos , grating , optoelectronics , optical amplifier , fiber optic sensor , long period fiber grating , laser , fiber laser , optical fiber , wavelength , dispersion shifted fiber , physics , archaeology , history
In this work, we explore the interrogation of an array of fiber Bragg gratings as part of a laser cavity. A semiconductor optical amplifier in a sigma-shaped fiber cavity provides gain and is gated periodically at a rate that matches the roundtrip time associated with each grating of the array. The interrogator exhibits clear laser properties such as a threshold and linewidth narrowing. Besides improving the signal-to-noise ratio and enabling the re-use of wavelengths, it is found that this interrogation scheme enables monitoring of weak gratings spaced by less than 1 cm. Intracavity grating interrogation studied here is found to be a simple and powerful way to increase the number of sensor points for industrial applications.