Liquid crystal display apparatus

• US 20060221260A1
• Filed: 03/27/2006
• Published: 10/05/2006
• Est. Priority Date: 03/30/2005
• Status: Abandoned Application

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Fujine, Toshiyuki, Sugino, Michiyuki, Niiyama, Ryuichi, Kohashikawa, Seiji
• Application Number:
  US11/389,170
• Publication Number:
  US 20060221260A1
• Time in Patent Office: Days
• US Class Current: 348/790
• CPC Class Codes: G09G 2320/062 Adjustment of illumination source parameters
• 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 2320/0666 for control of colour parameters, e.g. colour temperature
• CPC Class Codes: G09G 2320/0673 for control of gamma adjustment, e.g. selecting another gamma curve
• CPC Class Codes: G09G 2330/021 Power management, e.g. power saving
• 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 3/3611 Control of matrices with row and column drivers

Abstract

A display apparatus is provided which can achieve suitable screen display luminance depending on video content as well as can reduce power consumption sufficiently. A liquid crystal display apparatus includes a liquid crystal panel that displays video and a light source that illuminates the liquid crystal panel, and the emission luminance of the light source is controlled depending on the genre of the video displayed on the liquid crystal panel. The emission luminance of the light source is adjusted while maintaining approximately constant white chromaticity (white balance).

Claims

1. A liquid crystal display apparatus comprising:

a liquid crystal panel that displays video, and a light source that illuminates the liquid crystal panel,

wherein an emission luminance characteristic of the light source for a feature quantity of an input video signal is changed depending on a genre of video displayed on the liquid crystal panel.

2. The liquid crystal display apparatus of claim 1, wherein by changing the emission luminance characteristic of the light source for the feature quantity of the input video signal, a characteristic changing point is changed, the characteristic changing point being a point where a slope indicating the emission luminance characteristic of the light source for the feature quantity of the input video signal is changed.

3. The liquid crystal display apparatus of claim 1, wherein by changing the emission luminance characteristic of the light source for the-feature quantity of the input video signal, an approximate characteristic changing point is changed, the approximate characteristic changing point indicating an intersecting point when the emission luminance characteristic corresponding to the feature quantity of the input video signal is approximated by lines.

4. The liquid crystal display apparatus of claim 1, wherein by changing the emission luminance characteristic of the light source for the feature quantity of the input video signal, a difference between the maximum value and minimum value of the emission luminance of the light source is changed.

5. The liquid crystal display apparatus of claim 1, wherein the input video signal is extended or compressed and wherein the emission luminance characteristic of the light source for the feature quantity of the input video signal is changed.

6. The liquid crystal display apparatus of claim 1, wherein a gray scale level characteristic of the input video signal is corrected and wherein the emission luminance characteristic of the light source for the feature quantity of the input video signal is changed.

7. The liquid crystal display apparatus of claim 1, wherein a gray scale level transformation characteristic for the input video signal is changed and wherein the emission luminance characteristic of the light source for the feature quantity of the input video signal is changed.

8. The liquid crystal display apparatus of claim 1, wherein the change in the emission luminance of the light source is performed based on a lookup table selected depending on the genre of the video displayed on the liquid crystal panel.

9. The liquid crystal display apparatus of claim 1, wherein the change in the emission luminance of the light source is performed based on a computing equation selected depending on the genre of the video displayed on the liquid crystal panel.

10. The liquid crystal display apparatus of claim 9, wherein the computing equation is a function expression for obtaining the emission luminance of the light source corresponding to the feature quantity of the input video signal.

11. The liquid crystal display apparatus of claim 1, wherein the feature quantity of the input video signal is an average picture level of the input video signal.

12. The liquid crystal display apparatus of claim 1, wherein the genre of the video displayed on the liquid crystal panel is determined by a genre code multiplexed in the input video signal.

13. The liquid crystal display apparatus of claim 1, wherein the genre of the video displayed on the liquid crystal panel is determined based on the past viewing history information.

14. A liquid crystal display apparatus comprising:

a liquid crystal panel that displays video, and a light source that illuminates the liquid crystal panel with white light,

wherein, depending on a genre of the video displayed on the liquid crystal panel, increase and decrease of the emission luminance of the light source are adjusted while maintaining approximately constant chromaticity of the white.

15. The liquid crystal display apparatus of claim 14, wherein the genre of the video displayed on the liquid crystal panel is determined by a genre code multiplexed in the input video signal.

16. The liquid crystal display apparatus of claim 14, wherein the genre of the video displayed on the liquid crystal panel is determined based on the past viewing history information.