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:
Aug. 22, 2006
Filed:
Apr. 19, 2002
Masahiro Kawashima, Ibaraki, JP;
Hitoshi Noda, Suita, JP;
Takaaki Gyoten, Kobe, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
An APL detection unit detects the APL for each unit field time period of an input video signal, and a light source control data production unit produces, depending on the results of the APL detection, a light source control signal at a minimum level which can stably drive a light source when the APL is 0% up to a predetermined value A1, a light source control signal at a maximum level which can stably drive the light source when the APL is a predetermined value A2 up to 100%, and a light source control signal which dynamically varies depending on the APL when the APL is between the predetermined value A1 and the predetermined value A2, to drive the light source on the basis of the light source control signal. As a result, it is possible to mitigate the lack of a contrast feeling and the occurrence of a floating blackness, as well as to improve the reliability of the light source.