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:
Mar. 05, 1985
Filed:
Oct. 18, 1982
Otis G Zehl, College Park, MD (US);
Michael G Price, Seabrook, MD (US);
Edward H David, Jr, College Park, MD (US);
Litton Systems, Inc., College Park, MD (US);
Abstract
A device for detecting the centroid of a beam of electromagnetic energy is shown including means for focusing the beam into a blur spot upon a focal plane. Photodetectors located at the focal plane detect the centroid of the blur spot on either side of its nominal location. The intensity of the output from each photodetector is then measured and the difference and sum of these measurements obtained. By dividing the difference by the sum of the resultant signals, it is possible to produce an analog signal which represents the location of the blur spot centroid regardless of its amplitude. This arrangement has particular application in acousto-optic devices for measuring the frequency and direction of arrival of an incoming radio frequency wave.