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:
Dec. 11, 2001
Filed:
Mar. 16, 1999
Robert A. Mitchell, Woodland Hills, CA (US);
Stuart A. Mills, West Hills, CA (US);
James Ryan, Van Nuys, CA (US);
Litton Systems, Inc., Agoura Hills, CA (US);
Abstract
An improved optical correlator using a coherent light beam employs a method of adaptive alignment. A test pattern modulates an input spatial light modulator. The modulated beam propagates through passive transforming optical elements to a filter spatial light modulator, which is simultaneously modulated with an independently transformed frequency domain reference. The resulting correlation or coincidence of the optically transformed pattern with the independently transformed reference is processed to yield a feedback signal indicative of any optical misalignment of the optical correlator. The feedback signal drives a beam deflector to compensate by adjusting the path of the coherent beam, thereby improving and maintaining optical alignment of the correlator.