The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 13, 1991
Filed:
Sep. 13, 1989
Herve J Arditty, Marly Le Roi, FR;
Philippe Martin, Pontchartrain, FR;
Francois X Desforge, Fontenay Le Fleury, FR;
Phillipe Graindorge, Crimolois, FR;
Herve Lefevre, Paris, FR;
Phononetics, S.A., , FR;
Abstract
The invention relates to an optical fiber measuring device of the type in which variation of a measured parameter causes a difference of progression of light waves in the optical fiber. Such a device permits measurement of speed of rotation, or of current and magnetic field. The device includes an electronic device for digitally processing a signal indicative of phase shift of one light wave relative to another, the light waves propagating through a preferably monomode optical fiber in a SAGNAC ring interferometer, modulated by a phase modulator. The electronic device includes an analog-digital converter 11, a digital processing system 12 for generating a processor signal reduced to a frequency of modulation around the optical fiber, a control loop digital filter 13 for supplying a parameter indication signal, a register 14 for receiving the parameter indication signal and supplying a register signal which is a function of the measured parameter, an accumulator 15 for generating a digital feedback signal which is a function of the measured parameter, and a digital-analog converter 16 for generating an analog feedback signal for controlling the phase modulator.