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. 02, 2005
Filed:
Aug. 08, 2000
Masayuki Bannai, Kanagawa-ken, JP;
Masayuki Bannai, Kanagawa-ken, JP;
Fujitsu General Limited, Kawasaki, JP;
Abstract
A contrast adjusting circuit used in a PDP display prevents the image from being whitish by suppressing the rise of the luminance at a low level when the contrast is heightened and optimally adjusts the contrast of the images always varying with time. The circuit contains an average luminance calculating section (), an LUT (), and an output video data calculating section (), wherein the average luminance calculating section () determines the average luminance level APL for n frame images from the input video data X (X>=0) on the X-Y coordinate system, the LUT () determines central value data Xc, Yc from the APL, and the output video data calculating section () determines the output video data Y (Y>=0) collected after the contrast is adjusted according to the calculation formula Y=A·X+Yc−A·Xc where A (A>0) is the slope variably set for contrast adjustment, whereby the rise of the luminance at a low level when A is increased and the contrast is heightened, is suppressed to adjust the contrast corresponding to the APL for frame images.