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. 03, 1981
Filed:
Jan. 26, 1978
Kozo Nakahata, Yokohama, JP;
Hitachi, Ltd., , JP;
Abstract
A raster, for example in magenta, generated on a phosphor screen of a color picture tube is picked up by a television camera through an optical filter which allows a magenta component to pass therethrough predominantly. The television camera scans the displayed raster in the horizontal direction on the line base thereby to produce a video signal representing luminances at individual points on the raster lines. A sample and hold circuit is provided to extract paired video signal values at paired points on the raster lines located symmetrically to each other relative to a vertical center line of the display screen. One of the paired video signal values extracted through the timed sampling operation is subtracted from the other at a processing circuit.