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:
Dec. 14, 1993
Filed:
May. 13, 1991
Herve Lefevre, Paris, FR;
Philippe Martin, Fresnes, FR;
Pascal Simonpietri, Sanit Brice Sous Foret, FR;
Photonetics, S.A., , FR;
Abstract
The invention relates to a fiber optic measuring device in which the variation in a measured parameter engenders a phase difference between two waves. It comprises a SAGNAC ring interferometer (2) in which two counter-propagating waves propagate; a polarization splitter (6) spatially splits the two polarizations which will propagate in the interferometer (2), interferometer (2) comprises a polarization conserving birefringent fiber (7) having two ends having neutral birefringence axes, each of the ends of the polarization conserving fiber (7) being connected to one of the gates (6b) and (6c) of the polarization splitter (6). It comprises a birefringent component, placed ahead of the polarization splitter (6) and introducing a path difference greater than the coherence length of the source (1) between the two polarized waves.