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:
Oct. 03, 1995
Filed:
Feb. 24, 1994
Yozo Nishiura, Osaka, JP;
Yasuhiko Nishi, Osaka, JP;
Sumitomo Electric Industries, Ltd., Osaka, JP;
Abstract
An AC component of the photodetector includes two quasi-sine waves in a cycle of phase-modulation. T.sub.1 and T.sub.2 are time lengths of the quasi-sine waves. When a fiber coil is rotating, T.sub.1 differs from T.sub.2. The difference between T.sub.1 and T.sub.2 is in proportion to an angular velocity of the fiber coil. This invention obtains the angular velocity by measuring time durations T.sub.1, T.sub.2 or both T.sub.1 and T.sub.2. Zero-crossing detection defines the moments of the beginning and the end of T.sub.1 and T.sub.2. Since this gyroscope depends on the measurement of time lengths, it is fully immune from the fluctuation of light power due to the light source, or the fluctuation of the gain in the electric circuit.