Patent ID: 7777890
Filing Date: 2010-08-17
Classification: G01C

Abstract:
1. Optical-fibre measuring device in which the variation of a measured parameter generates a phase difference between two waves, including: a wide-spectrum light source with a light power P, a Sagnac ring interferometer, preferably single-mode, in which propagate two counter-propagating waves, the wave propagation time between the separation and recombination thereof being τ, a detector receiving a light flux from the interferometer and converting it into an electrical signal representing the total phase difference δφ an optical phase modulator generating a phase difference δφ electronic means receiving the electrical signal from the detector and providing a first signal S said first signal function of the measured parameter producing an optical phase modulator first control signal V said electronic means including a demodulator contributing to provide the first signal function of the measured parameter, said electronic means providing a second signal S characterized in that the optical phase modulator generates a disturbance component δφ