Method of compensating for pixel data and liquid crystal display

• US 8,890,794 B2
• Filed: 07/26/2010
• Issued: 11/18/2014
• Est. Priority Date: 11/23/2009
• Status: Active Grant

• Current Assignee: LG Display Co., Ltd.
• Original Assignee: LG Display Co., Ltd.
• Inventors: Kim, Dongwoo, Hong, Heejung, Kwon, Kyungjoon, Ahn, Heewon, Cho, Daeho
• Primary Examiner(s): SHERMAN, STEPHEN G
• Application Number:
  US12/843,263
• Publication Number:
  US 20110122170A1
• Time in Patent Office: 1,576 Days
• Field of Search: 345 87-104, 345/204, 345/213, 345690-699
• US Class Current: 345/102
• CPC Class Codes: G09G 2320/0646 Modulation of illumination source brightness and image signal correlated to each other
• CPC Class Codes: G09G 2320/066 for control of contrast
• CPC Class Codes: G09G 3/3406 Control of illumination source illumination devices structurally associated with liquid crystal cells G02F1/1336
• CPC Class Codes: G09G 3/3648 using an active matrix G09G3/367 - G09G3/3696 take precedence

Abstract

A method of compensating for pixel data includes extending a side portion and a corner portion of a real screen to set an virtual screen, setting dimming values of the virtual screen using dimming values of the real screen, calculating an amount of light of each of pixels on the real screen using the dimming values of the virtual screen mapped to a predetermined analysis area, and multiplying the amount of light of each pixel by a gain of each pixel to modulate pixel data.

Claims

1. A method of compensating for pixel data comprising:

extending a side portion and a corner portion of a real screen to set an virtual screen;

setting dimming values of the virtual screen using dimming values of the real screen;

calculating an amount of light of each of pixels on the side portion and the corner portion of the real screen by adding dimming values of blocks belonging to a predetermined analysis area including the real screen and the virtual screen; and

multiplying the amount of light of each pixel by a gain of each pixel to modulate pixel data,

wherein a size of the virtual screen is based on a size of the predetermined analysis area.

2. The method of claim 1, wherein the setting of the dimming values of the virtual screen comprises reproducing the dimming values of the real screen in a side portion and a corner portion of the virtual screen in a mirror-symmetrical manner.

3. The method of claim 1, wherein a width and a height of the size of the virtual screen is greater than a width and a height of the size of the real screen by approximately a width and a height of the size of the predetermined analysis area.

4. A liquid crystal display comprising:

a liquid crystal display panel;

a backlight unit configured to provide light to the liquid crystal display panel;

a light source driver configured to drive light sources of the backlight unit;

a local dimming controller configured to divide the liquid crystal display panel into a plurality of blocks, calculate a dimming value of each block, control the light source driver using the dimming value of each block, and modulate pixel data of the liquid crystal display panel,

wherein the local dimming controller extends a side portion and a corner portion of a real screen to set an virtual screen, sets dimming values of the virtual screen using dimming values of the real screen, calculates an amount of light of each of pixels on the side portion and the corner portion of the real screen by adding dimming values of blocks belonging to a predetermined analysis area including the real screen and the virtual screen, and multiplies the amount of light of each pixel by a gain of each pixel to modulate pixel data,

wherein a size of the virtual screen is based on a size of the predetermined analysis area.

5. The liquid crystal display of claim 4, wherein the local dimming controller reproduces the dimming values of the real screen in a side portion and a corner portion of the virtual screen in a mirror-symmetrical manner.

6. The liquid crystal display of claim 4, wherein a width and a height of the size of the virtual screen is greater than a width and a height of the size of the real screen by approximately a width and a height of the size of the predetermined analysis area.