Image display device and image display method of a multi-display type with local and global control

• US 9,368,072 B2
• Filed: 03/22/2012
• Issued: 06/14/2016
• Est. Priority Date: 03/29/2011
• Status: Active Grant

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Otoi, Katsuya, Hashimoto, Katsuteru
• Primary Examiner(s): Crawley, Keith
• Application Number:
  US14/000,262
• Publication Number:
  US 20130321498A1
• Time in Patent Office: 1,545 Days
• Field of Search: 345/1.3, 345/102, 345/690, 345/694
• US Class Current: 1/1
• CPC Class Codes: G02F 1/13336 Combining plural substrates to produce large-area displays, e.g. tiled displays
• CPC Class Codes: G02F 1/133601 for spatial active dimming
• CPC Class Codes: G02F 1/133603 with LEDs
• 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 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 3/3426 the different display panel areas being distributed in two dimensions, e.g. matrix
• CPC Class Codes: G09G 3/3611 Control of matrices with row and column drivers

Abstract

Control sections of displays 11 each determine control information Pi used when area-active driving is performed individually and transmit the control information Pi to a multi-display control section 12. The multi-display control section 12 determines control information Ps for the entire device on the basis of the received pieces of control information Pi and transmits the control information Ps to the control sections of the displays 11. All the displays 11 perform area-active driving on the basis of the same control information Ps. In this way, occurrence of a luminance difference or chromaticity difference among display screens of the displays 11 is prevented and the quality of a displayed image is improved.

Claims

1. An image display device of multi-display type, comprising:

a plurality of image display sections each including a display panel, a backlight, and a local controller configured or programmed to perform area-active driving; and

a global controller configured or programmed to transmit and receive control information to and from the local controllers, wherein;

the local controllers each determine local control information and transmit the local control information to the global controller,

the local control information being control information used when area-active driving is performed individually,

the global controller determines global control information on the basis of the local control information received from the local controllers and transmits the global control information to the local controllers,

the global control information being control information for the entire device,

the local controllers each operate on the basis of the global control information received from the global controller,

the local control information and the global control information each include information related to control of light transmittance of the display panel,

the local control information and the global control information each include information related to control of luminance of the backlight,

the local control information and the global control information each include a lowest emission luminance compensation vane which indicates the lowest luminance of light to be emitted by the backlight,

the local controllers correct luminance of light to be emitted by the backlight on the basis of the lowest emission luminance compensation value received from the global controller, and

the global controller transmits, to the local controllers, the maximum vane among the lowest emission luminance compensation values received from the local controllers.

2. The image display device according to claim 1, wherein

the local controllers each determine, on the basis of an average luminance level of an input image, the lowest emission luminance compensation value to be transmitted to the global controller.

3. The image display device according to claim 1, wherein:

the local control information and the global control information each include a clipping scale value which indicates a degree of clipping that occurs in display data for use in driving of the display panel, and

the local controllers each determine the display data on the basis of the clipping scale value received from the global controller.

4. The image display device according to claim 3, wherein

the global controller transmits, to the local controllers, the maximum value among the clipping scale values received from the local controllers.

5. The image display device according to claim 3, wherein

the local controllers each determine, on the basis of temporary display data based on an input image, the clipping scale value to be transmitted to the global controller.

6. An image display device of multi-display type, comprising:

a plurality of image display sections each including a display panel, a backlight, and a local controller configured or programmed to perform area-active driving; and

a global controller configured or programmed to transmit and receive control information to and from the local controllers, wherein;

the local controllers each determine local control information and transmit the local control information to the global controller,

the local control information is control information used when area-active driving is performed individually,

the global controller determines global control information on the basis of the local control information received from the local controllers and transmits the global control information to the local controllers,

the global control information is control information for the entire device,

the local controllers each operate on the basis of the global control information received from the global controller, and

the global controller transmits, to the local controllers, a maximum value among lowest emission luminance compensation values received from the local controllers.

7. The image display device according to claim 6, wherein

the local control information and the global control information each include information related to control of luminance of the backlight.

8. The image display device according to claim 7, wherein:

the local control information and the global control information each include a lowest emission luminance compensation value which indicates the lowest luminance of light to be emitted by the backlight, and

the local controllers each correct luminance of light to be emitted by the backlight on the basis of the lowest emission luminance compensation value received from the global controller.

9. The image display device according to claim 8, wherein

the local controllers each determine, on the basis of an average luminance level of an input image, the lowest emission luminance compensation value to be transmitted to the global controller.

10. The image display device according to claim 6, wherein

the local control information and the global control information each include information related to control of light transmittance of the display panel.

11. The image display device according to claim 10, wherein:

the local control information and the global control information each include a clipping scale value which indicates a degree of clipping that occurs in display data used in driving of the display panel, and

the local controllers each determine the display data on the basis of the clipping scale value received from the global controller.

12. The image display device according to claim 11, wherein

the global controller transmits, to the local controllers, the maximum value among the clipping scale values received from the local controllers.

13. The image display device according to claim 11, wherein

the local controllers each determine, on the basis of temporary display data based on an input image, the clipping scale value to be transmitted to the global controller.

14. The image display device according to claim 6, wherein

the local control information and the global control information each include both information related to control of luminance of the backlight and information related to control of light transmittance of the display panel.