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. 13, 1987
Filed:
Mar. 27, 1985
Robert W Brandstetter, Levittown, NY (US);
Adrian R Doucette, deceased, late of Garden City, NY (US);
Herman Kaplan, Great Neck, NY (US);
Charles E Lindig, Huntington, NY (US);
Nils J Fonneland, Lake Ronkonkoma, NY (US);
Grumman Aerospace Corporation, Bethpage, NY (US);
Abstract
An optical notching filter in which a band of radio frequencies such as the RF input of a radio receiver is an input signal. The input signal modulates a laser beam and the modulated beam is optically Fourier transformed. A programmable optical notching filter spatially filters the electromagnetic interference noise from the transformed beam and the thus filtered beam is optically inverse Fourier transformed. A photo-combining of the filtered beam with a focused laser local oscillator beam down-converts the filtered beam to the original input signal minus electromagnetic interference.