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:
May. 27, 1986
Filed:
Nov. 29, 1983
Friedemann Mohr, Renningen, DE;
International Standard Electric Corporation, New York, NY (US);
Abstract
In the rotation rate measuring instrument, two component beams derived from a light beam produced by a laser circulate around a coiled optical waveguide (radius R, length L) in opposite directions. From the phase difference between the two component beams due to the Sagnac effect, the rotation rate is determined. Before entering the optical waveguide, each of the two component beams is modulated in a modulator (5, 6) such that the phase differences (2.nu.+1).pi./2, (2.nu.+5).pi./2, and (2.nu.+3).pi./2 (where .nu. is an arbitrary integer) exist periodically between the two component beams emerging from the optical waveguide. The drive signals for the two modulators, which exhibit periodic frequency changes of 2F, are varied in such a way that the output of an optical-to-electrical transducer (2) to which the two component beams are directed after travelling around the optical waveguide provides a constant signal. To compensate for the Sagnac phase difference, an additional frequency difference of .DELTA.f is required between the two drive signals. The rotation rate .OMEGA. is determined by the equation ##EQU1## where .lambda.=vacuum wavelength of the light, and C=velocity of light in vacuo.