LIQUID CRYSTAL DISPLAY, AS WELL AS, A BACKLIGHT CONTROLLER AND A METHOD FOR THE SAME

• US 20080117160A1
• Filed: 05/14/2007
• Published: 05/22/2008
• Est. Priority Date: 11/20/2006
• Status: Active Grant

• Current Assignee: Maxell, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Oka, Naoya, Nagashima, Yoshiyuki
• Granted Patent: US 7,825,893 B2
• Time in Patent Office: Days
• US Class Current: 345/102
• CPC Class Codes: G09G 2320/0633 by amplitude modulation of the brightness of the illumination source
• CPC Class Codes: G09G 2360/16 Calculation or use of calculated indices related to luminance levels in display data
• CPC Class Codes: G09G 3/3406 Control of illumination source illumination devices structurally associated with liquid crystal cells G02F1/1336
• CPC Class Codes: G09G 3/36 using liquid crystals

Abstract

A liquid crystal display, comprising: a liquid crystal display portion for inputting a video signal to display an image thereon; a backlight provided on a rear side of the liquid crystal display portion, for illuminating the liquid crystal display portion from a rear surface thereof; a backlight driver portion for driving the backlight, also having a light control function for controlling a light intensity of the illuminating lights from that backlight; a feature detector portion for detecting an averaged brightness of the video signal, and also a histogram of brightness or a color, upon basis of said video signal inputted; and a light intensity control portion for controlling the light intensity of the illuminating lights from the backlight, through the light control function of the backlight driver portion, upon basis of the histogram of brightness or color, as well as, the averaged brightness of the video signal detected by the feature detector portion.

Claims

1. A liquid crystal display, comprising:

a liquid crystal display portion, which is configured to input a video signal to display an image thereon;

a backlight, which is provided on a rear side of said liquid crystal display portion, and is configured to illuminates said liquid crystal display portion from a rear surface thereof;

a backlight driver portion, which is configured to drive said backlight, and also to have a light control function for controlling a light intensity of the illuminating lights from said backlight;

a feature detector portion, which is configured to detect an averaged brightness of said video signal and also a histogram of brightness or a color, upon basis of said video signal inputted; and

a light intensity control portion, which is configured to control the light intensity of the illuminating lights from said backlight, through the light control function of said backlight driver portion, upon basis of said histogram of brightness or color and also said averaged brightness of said video signal detected by said feature detector portion.

2. The liquid crystal display, as described in claim 1, wherein said light intensity control portion controls the light intensity of the illuminating lights from said backlight, upon basis of pattern said histogram of brightness or color and also said averaged brightness of said video signal detected by said feature detector portion.

3. The liquid crystal display, as described in claim 2, wherein said light intensity control portion includes a memory portion, which is configured to memorized the light intensity of the illuminating lights from said backlight, which is determined in advance, upon basis of the pattern said histogram of brightness or color and also said averaged brightness of said video signal detected by said feature detector portion.

4. A backlight controller for controlling an intensity of illumination lights from a backlight for illuminating a liquid crystal display portion from a rear surface thereof, comprising:

a backlight driver portion, which is configured to drive said backlight, and also to have a light control function for controlling a light intensity of the illuminating lights from said backlight;

a feature detector portion, which is configured to detect an averaged brightness of said video signal and also a histogram of brightness or colors, upon basis of said video signal inputted; and

a light intensity control portion, which is configured to control the light intensity of the illuminating lights from said backlight, through the light control function of said backlight driver portion, upon basis of said histogram of brightness or color and also said averaged brightness of said video signal detected by said feature detector portion.

5. The backlight controller, as described in claim 4, wherein said light intensity control portion controls the light intensity of the illuminating lights from said backlight, upon basis of pattern said histogram of brightness or color and also said averaged brightness of said video signal detected by said feature detector portion.

6. The backlight controller, as described in claim 5, wherein said light intensity control portion includes a memory portion, which is configured to memorized the light intensity of the illuminating lights from said backlight, which is determined in advance, upon basis of the pattern said histogram of brightness or color and also said averaged brightness of said video signal detected by said feature detector portion.

7. A backlight controlling method for controlling an intensity of backlight illumination lights for illuminating a liquid crystal display portion, inputting a video signal and displaying an image thereon, from a rear surface thereof, comprising the following steps of:

detecting an averaged brightness of said video signal and also a histogram of brightness or a color, upon basis of said video signal inputted; and

controlling the light intensity of the illuminating lights from said backlight, upon basis of said histogram of brightness or color and also said averaged brightness of said video signal detected.

8. The backlight controlling method, as described in claim 7, wherein the light intensity of the illuminating lights from said backlight is controlled, upon basis of pattern said histogram of brightness or color and also said averaged brightness of said video signal detected by said feature detector portion.

9. The backlight controlling method, as described in claim 8, wherein the light intensity of the illuminating lights from said backlight is determined, in advance, to be memorized, upon basis of the pattern said histogram of brightness or color and also said averaged brightness of said video signal detected by said feature detector portion.