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:
Jun. 07, 1994
Filed:
Apr. 16, 1992
Kenji Saito, Tokyo, JP;
Yoshio Nakane, Tokyo, JP;
Fuji Photo Film Company, Limited, Kanagawa, JP;
Abstract
A white balance control device for a video camera is provided to reduce an occurrence percentage and the degree of color failure, improve the quality of reproduced color and prevent flicker from occurring so that a photograph may be taken properly. A first microcomputer detects a brightness of an object and a condition of a divided light measurement judged from an open degree of an iris. The first microcomputer outputs white balance control signals Rcont and Bcont for equalizing the values of color difference signals R-Y and B-Y to reference values. A white balance control circuit changes the amplification degrees of an elementary red signal R and an elementary blue signal B. When a brightness of an object becomes higher than the previous memorized value and a mode of a divided light measurement is changed, values of white balance control signals Rcont and Bcont are changed. At the other times, the values of the white balance control signals Rcont and Bcont are fixed. The determined values are divided to an area for an inside of an house mode and a outside of a house mode. The quality of reproduced colors is improved by controlling the gain and the hue in a matrix circuit. Under a fluorescent lamp, an electric shutter is actuated with a shutter speed of 1/100 second in order to prevent flicker from occurring.