A method for detecting a fault of an optical-fiber gyro, and an apparatus for diagnosing a fault of the same
CA 2135809 C · Owner: Kumagai, Tatsuya · Inventors: Kajioka, Hiroshi; Akiyama, Munehiro; Oho, Shigeru
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A phase-modulated light stream is propagated through an optical-fiber sensing loop, from which a propagated light stream is obtained. The propagated light stream is converted to an electric signal, from which a fundamental-wave component and even-number harmonic-wave components for the phase-modulated signal are detected. In accordance with the changes of the fundamental- and even-number harmonic-wave components a fault, is detected. On the other hand the electric signal may be, integrated to provide an integrated signal. In accordance with the comparison between the integrated signal and a fault reference voltage, the fault may be detected.
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Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed November 15, 1994 and granted January 25, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended November 15, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 15, 2016.
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