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:
Jun. 11, 1996
Filed:
Nov. 25, 1994
Yozo Nishiura, Osaka, JP;
Sumitomo Electric Industries, Ltd., Osaka, JP;
Abstract
A source-sensitive gyroscope guides light beams emitted from a light emitting device into both ends of the fiber coil, makes the beams propagate in the coil clockwise and counterclockwise, and retrieves the beams into the light emitting device itself. The phase difference is obtained from the change of the driving current or the change of the driving voltage of the light emitting device, or from the change of a photocurrent of the monitoring photodetector mounted behind the light emitting device in the light source. A birefringent medium having an optical path difference longer than the coherent length of the light is interposed between the light emitting device and the end of the fiber. When the light beams are non-polarized, the birefringent medium is aligned in the orientation in which the anisotropic axis is perpendicular to the beam line. When the light beams are linearly polarized, the birefringent medium is arranged in the orientation in which the anisotropic axis inclines at 45 degrees to the linear polarization. When a polarizer is equipped in the beam line, the birefringent medium is arranged in the orientation in which the anisotropic axis inclines at 45 degrees to the linear polarization. In any case, the single birefringent medium plays the role of a substantial depolarizer.