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. 26, 1984
Filed:
Apr. 06, 1981
Wilbur A Carrington, Grand Rapids, MI (US);
Ronald J Fredricks, Grand Rapids, MI (US);
Harry L Gubbins, Grand Rapids, MI (US);
Gordon P Eckley, Grand Rapids, MI (US);
Thomas E Perfitt, Wyoming, MI (US);
Jerry L Page, Marlboro, MA (US);
Lear Siegler, Inc., Santa Monica, CA (US);
Abstract
An optical rate sensor (200) is disclosed for use in inertial reference systems to measure rates of angular rotation with substantially high resolution and sensitivity. The sensor (200) comprises a passive ring Sagnac interferometer (201) with a multiturn fiber optic ring (232) through which counter-propagating optical waves are transmitted. A nonreciprocal time variant phase modulation is applied to the waves along with periodic effective transposition of ring ports. The waves are combined to produce a 'zero order' fringe pattern having an intensity varying in accordance with the relative phase between the counter-propagating waves. An intensity signal is derived from the fringe pattern having a phase offset corresponding to the Sagnac induced phase shift which in turn is linearly proportional to the angular rotation rate of the passive ring. Sampling, averaging and estimation circuits detemine the offset by detecting zero-crossing locations of the signal.