Liquid Crystal Display Wall and Method for Controlling the Same

• US 20100328336A1
• Filed: 07/28/2009
• Published: 12/30/2010
• Est. Priority Date: 06/29/2009
• Status: Abandoned Application

• Current Assignee: Infovision Optoelectronics Company Limited (Digital China Information Service Co., Ltd.)
• Original Assignee: Infovision Optoelectronics Company Limited (Digital China Information Service Co., Ltd.)
• Inventors: SI, Bingyu
• Application Number:
  US12/511,064
• Publication Number:
  US 20100328336A1
• Time in Patent Office: Days
• US Class Current: 345/589
• CPC Class Codes: G09G 2300/026 Video wall, i.e. juxtaposition of a plurality of screens to create a display screen of bigger dimensions
• CPC Class Codes: G09G 2320/0626 for control of overall brightness
• CPC Class Codes: G09G 2320/0646 Modulation of illumination source brightness and image signal correlated to each other
• CPC Class Codes: G09G 2360/16 Calculation or use of calculated indices related to luminance levels in display data
• CPC Class Codes: G09G 3/3666 with the matrix divided into sections

Abstract

The present invention relates to liquid crystal display wall and method for controlling the same. An LCD wall according to an embodiment of the invention comprises a display array and a control device, wherein the display array comprises a display panel and a backlight device, and the control device comprises a backlight controller configured to control the backlight device in the display array, and a display controller configured to receive image data and control the display of the image data on the display panel, wherein the display controller is further configured to perform adjustment in grey-scale on the image data corresponding to a backlight brightness of the backlight device. According to the embodiments of the invention, the LCD wall can perform dynamic backlight control, and can output grey-scales with a good uniformity.

Claims

1. An LCD wall comprising a display array and a control device, wherein

the display array comprises a display panel and a backlight device,

the control device comprises:

a backlight controller configured to control the backlight device in the display array, and

display controller configured to receive image data and control the display of the image data on the display panel,

wherein the display controller is further configured to perform adjustment grey-scale on the image data corresponding to a backlight brightness of the backlight device.

2. The LCD wall according to claim 1, wherein the display controller comprises:

a detection unit for receiving the image data and performing a bright/dim determination on the display units contained in the display panel based on image frames contained in the image data to determine whether the display unit corresponding to each of the image frames is a bright unit or a dim unit;

a Gamma adjusting unit for adjusting a Gamma parameter of the image frame in each display unit that has been determined to be a dim unit;

a spatial filter unit for performing a spatial smoothing filtering on the image frame in each display unit that has been determined to be a dim unit;

a temporal filer unit for performing a temporal smoothing filtering on the sequentially displayed image frames in each display unit that has been determined to be a dim unit;

a uniformity adjusting unit for performing a spatial smoothing filtering among the display units; and

a memory unit for storing the data in association with the image frames that have been displayed for the temporal smoothing filtering.

3. The LCD wall according to claim 2, wherein the Gamma adjusting unit is configured to decrease grey-scale values of dim pixels in the image frame while maintain grey-scale values of bright pixels substantially unchanged, the dim pixel being a pixel having a grey-scale value lower than a grey-scale threshold, the bright pixel being a pixel having a grey-scale value not lower than the grey-scale threshold.

4. The LCD wall according to claim 2, wherein the detection unit is configured to perform the bright/dim determination by calculation of statistical distribution of energy based on a grey-scale histogram of the image frame.

5. The LCD wall according to claim 4, wherein the display unit corresponding to the image frame is determined to be a dim unit if a ratio of the pixels having a grey-scale value lower than a grey-scale threshold among the pixels in the image frame is higher or equal to a ratio threshold, and is determined to be a bright unit if a ratio of the pixels having a grey-scale value lower than the grey-scale threshold among the pixels in the image frame is lower than the ratio threshold.

6. The LCD wall according to claim 1, wherein

the display panel comprises a plurality of display units each of which comprises a plurality of display regions;

the backlight device comprises a plurality of backlight regions provided correspondingly to the display regions in a one-to-one correspondence; and

the backlight regions of the backlight device are independently controlled by the backlight controller so as to provide backlighting for the respective display regions independently.

7. The LCD wall according to claim 6, wherein the backlight controller is configured to control the backlight regions of the backlight device by using pulse width modulation.

8. The LCD wall according to claim 6, wherein the backlight controller is configured to control the backlight regions of the backlight device by using analog continuous dimming.

9. The LCD wall according to claim 1, wherein the control device comprises a signal input device integrated therein and used to generate the image data.

10. A method for controlling an LCD wall comprising a display array and a control device, the display array comprising a display panel and a backlight device, the method comprising:

controlling the backlight device in the display array; and

receiving image data and controlling the display of the image data on the display panel,

wherein the controlling the display of the image data on the display panel comprises adjusting grey-scale on the image data corresponding to a backlight brightness of the backlight device.

11. The method according to claim 10, wherein the adjusting grey-scale on the image data comprises:

performing a bright/dim determination on the display units contained in the display panel based on the image frames contained in the image data;

adjusting a Gamma parameter of the image frame;

performing a spatial smoothing filtering on the image of each display unit;

performing a temporal smoothing filtering on the sequentially displayed images of each display unit; and

performing a spatial smoothing filtering among the display units.

12. The method according to claim 11, wherein the adjusting the Gamma parameter of the image frame comprises:

decreasing grey-scale values of dim pixels in the image frame while maintaining grey-scale values of bright pixels substantially unchanged, the dim pixel being a pixel having a grey-scale value lower than a grey-scale threshold, the bright pixel being a pixel having a grey-scale value not lower than the grey-scale threshold.

13. The method according to claim 11, wherein the bright/dim determination is made by calculation of statistical distribution of energy based on a grey-scale histogram of the image frame.

14. The method according to claim 13, wherein the display unit corresponding to the image frame is determined to be a dim unit if a ratio of the pixels having a grey-scale value lower than a grey-scale threshold among the pixels in the image frame is higher or equal to a ratio threshold, and is determined to be a bright unit if a ratio of the pixels having a grey-scale value lower than the grey-scale threshold among the pixels in the image frame is lower than the ratio threshold.

15. The method according to claim 10, wherein

the display array comprises a display panel and a backlight device,

the display panel comprises a plurality of display units each of which comprises a plurality of display regions;

the backlight device comprises a plurality of backlight regions provided correspondingly to the display regions in a one-to-one correspondence; and

the controlling the backlight device in the display array comprises controlling the backlight regions of the backlight device independently so as to provide backlighting for the respective display regions independently.

16. The method according to claim 15, wherein the control on the backlight device is made by using pulse width modulation.

17. The method according to claim 15, wherein the control on the backlight device is made by using analog continuous dimming.