Display device

• US 8,330,708 B2
• Filed: 06/08/2010
• Issued: 12/11/2012
• Est. Priority Date: 08/27/2009
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Park, Sangtae, Kim, Minchul, Kim, Sungwoo, Jung, Bupsung, Seo, Buwan, Ko, Myounghwa, Bae, Seungchoon, Kwon, Soonhyung
• Primary Examiner(s): OSORIO, RICARDO
• Application Number:
  US12/796,198
• Publication Number:
  US 20110050743A1
• Time in Patent Office: 917 Days
• Field of Search: 345/87, 345/102, 345/103, 345/65
• US Class Current: 345/102
• CPC Class Codes: G02F 1/133601 for spatial active dimming
• CPC Class Codes: G02F 1/133603 with LEDs
• CPC Class Codes: G09G 2320/0261 in the context of movement of objects on the screen or movement of the observer relative to the screen
• CPC Class Codes: G09G 2320/066 for control of contrast
• CPC Class Codes: G09G 3/3426 the different display panel areas being distributed in two dimensions, e.g. matrix
• CPC Class Codes: G09G 3/3666 with the matrix divided into sections

Abstract

The present invention relates to a display device, which includes: a backlight unit that is divided into a plurality of blocks, is driven for each divided block, and includes at least one optical assembly; a display panel disposed on the upper side of the backlight unit; a controller that outputs a local dimming value for each block corresponding to brightness of each block of the backlight unit according to images displayed on the display panel; and a BLU driver that controls the brightness of the blocks of the backlight unit by using the local dimming value for each block, wherein the optical assembly includes a first layer; a plurality of light sources that is formed on the first layer to emit light; a second layer that is disposed on the upper side of the first layer and is formed to cover the plurality of light sources; and a reflective layer that is disposed between the first and second layers, and the BLU driver receives the local dimming value for each block to output the plurality of driving signals, and the blocks of the backlight unit are divided into a plurality of scan groups and is driven in the divided group unit.

Claims

1. A display device, comprising:

a backlight unit that is divided into a plurality of blocks and is driven by the divided blocks, and includes at least one optical assembly;

a display panel positioned over the backlight unit;

a controller that outputs local dimming values corresponding to brightness of the blocks of the backlight unit, in accordance with an image displayed in the display panel; and

a BLU driver that controls the brightness of the blocks of the backlight unit using the local dimming values,

wherein the at least one optical assembly includes;

a first layer;

a plurality of light sources formed on the first layer to emit light, and each light source'"'"'s light emitting surface being vertical to the first layer,

wherein the light sources include at least one first light source and at least one second light source which are arranged in different rows, and a light emitting direction of the at least one first light source and a light emitting direction of the at least one second light source are in opposite directions based on the different rows;

a second layer disposed above the first layer to cover the light sources; and

a reflective layer that is disposed between the first and second layers, and

wherein the BLU driver receives the local dimming values and outputs a plurality of driving signals, and

the blocks of the backlight unit are divided into a plurality of scan groups and are driven by the divided scan groups.

2. The display device according to claim 1, wherein the BLU driver receives information on the local dimming values for each block and a timing when the scan groups are scanned, for at least one block belonging to the scan groups from the controller.

3. The display device according to claim 2, wherein information on a scanning timing is a delay time from a timing when a vertical synchronization signal is input to a timing when the scan groups are scanned.

4. The display device according to claim 2, wherein information on a scanning timing is a scan start signal that represents the timing when the scan groups are scanned.

5. The display device according to claim 1, wherein at least two of the scan groups have different numbers of blocks belonging thereto.

6. The display device according to claim 1, wherein each of the plurality of driving signals output from the BLU driver controls the brightness of at least two of the blocks of the backlight unit.

7. The display device according to claim 1, wherein the display panel is divided into a plurality of regions, and

the controller controls the brightness of the blocks of the backlight unit corresponding to the regions according to a luminance of each of the regions of the display panel.

8. The display device according to claim 1, wherein the BLU driver receives the local dimming values for each block from the controller by using serial peripheral interface (SPI) communication.

9. The display device according to claim 1, wherein the first layer is a substrate on which the light is sources are mounted.

10. The display device according to claim 1, wherein the second layer includes a silicon-based resin or an acrylic-based resin.

11. The display device according to claim 1, wherein the second layer includes a plurality of scattering particles.

12. The display device according to claim 1, further comprising a light-shielding pattern formed on the second layer to correspond to a position of the light sources.

13. The display device according to claim 1, wherein the backlight unit includes a plurality of optical assemblies.

14. The display device according to claim 1, wherein a thickness of the second layer is 0.1 mm to 4.5 mm.

15. The display device according to claim 1, wherein the light sources included in the at least one optical assembly are divided and driven into at least two blocks.

16. A display device comprising:

a backlight unit that is divided into a plurality of blocks and is driven by the divided blocks, and includes at least one optical assembly;

a display panel positioned over the backlight unit;

a controller that outputs local dimming values corresponding to brightness of the blocks of the backlight unit, in accordance with an image displayed in the display panel; and

a BLU driver that controls the brightness of the blocks of the backlight unit using the local dimming values,

wherein the at least one optical assembly includes;

a first layer;

a plurality of light sources formed on the first layer to emit light, and each light source'"'"'s light emitting surface being vertical to the first layer;

wherein the light sources include at least one first light source and at least one second light source which are arranged in different rows, and a light emitting direction of the at least one first light source and a light emitting direction of the at least one second light source are in opposite directions based on the different rows;

a second layer disposed above the first layer to cover the light sources; and

a reflective layer that is disposed between the first and second layers, and wherein the blocks of the backlight unit are divided into a plurality of scan groups and are driven by the divided scan groups,

the BLU driver includes a driving unit, and

the driving unit includes a controller that receives local dimming values from the controller and a plurality of driver ICs outputting driving signals for controlling the brightness of the two or more blocks respectively.

17. The display device according to claim 16, wherein the controller, in parallel, outputs the local dimming values for each block inputted in series and transmits the local dimming values to each of the plurality of driver ICs.

18. The display device according to claim 16, wherein the driver IC supplies driving signals to the light sources included in n blocks by using n channels.

19. The display device according to claim 16, wherein the BLU driver includes a plurality of driving units.

20. The display device according to claim 16, wherein the plurality of light sources included in the at least one optical assembly are divided and driven into at least two blocks.

21. The display device according to claim 16, wherein the backlight unit includes a plurality of optical assemblies.