Optical fiber interferometer and method for measuring a magnetic field or a current based on an optical fiber interferometer - Patents.com

Abstract

The invention relates to an optical fiber interferometer comprising a light source (20), a differential phase modulator (16), a signal processing system (900) and a detection optical fiber (73) with a Verdet constant capable of inducing a non-reciprocal magneto-optical Faraday effect, the interferometer being capable of detecting a phase difference of an interference beam (300) formed by interference between two polarized waves (111, 112) traveling simultaneously along a closed optical path through the optical fiber (73) and deriving therefrom a value of the magnetic field or a value of the current flowing in the conductor (120) by dividing the phase difference by a scaling factor. According to the invention, the signal processing system (900) is suitable for measuring the variation of the power contrast of a portion of the interference beam and for deriving a measure of the variation of the scaling factor from the variation of the contrast.

Images