BACKLIGHT ASSEMBLY AND DISPLAY DEVICE HAVING THE SAME

• US 20090302780A1
• Filed: 05/20/2009
• Published: 12/10/2009
• Est. Priority Date: 06/05/2008
• Status: Active Grant

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: KIM, Chang-Hoi, SHIN, Jin-Soo
• Granted Patent: US 8,052,296 B2
• Time in Patent Office: Days
• US Class Current: 315/294
• CPC Class Codes: G02F 1/133601 for spatial active dimming
• CPC Class Codes: G02F 1/133603 with LEDs
• CPC Class Codes: G02F 1/133605 including specially adapted reflectors
• CPC Class Codes: G02F 1/133612 Electrical details
• CPC Class Codes: H05B 45/325 Pulse-width modulation [PWM]
• CPC Class Codes: H05B 45/35 Balancing circuits

Abstract

A backlight assembly includes a receiving container, a light-generating unit and a reflective sheet. The receiving container includes a bottom plate and a sidewall. The sidewall extends upwardly from an edge portion of the bottom plate to form a receiving space. The light-generating unit includes a light-emitting substrate disposed in the receiving space, light-emitting diodes (LEDs) and a driving circuit. The light-emitting substrate includes a light-emitting region and a peripheral region. The LEDs are disposed in the light-emitting region. The driving circuit disposed in the peripheral region controls the LEDs. The reflective sheet includes a center portion and a cover portion. The center portion is disposed on the light-emitting region. The cover portion is disposed on the peripheral region to cover the driving circuit.

Claims

1. A backlight assembly comprising:

a receiving container comprising a bottom plate and a sidewall upwardly extending from an edge portion of the bottom plate to form a receiving space;

a light-generating unit comprising;

a light-emitting substrate disposed in the receiving space, the light-emitting substrate including a light-emitting region and a peripheral region disposed outside of the light-emitting region;

a plurality of light-emitting diodes (LEDs) disposed in the light-emitting region; and

a driving circuit disposed in the peripheral region, the driving circuit controlling the LEDs; and

a reflective sheet comprising;

a center portion disposed on the light-emitting region, the center portion including a plurality of holes through which the LEDs respectively pass; and

a cover portion disposed on the peripheral region to cover the driving circuit, the cover portion being attached to the sidewall.

2. The backlight assembly of claim 1, wherein the cover portion is outwardly inclined with respect to the bottom plate.

3. The backlight assembly of claim 1, wherein the sidewall comprises:

a side part upwardly extending from the edge portion of the bottom plate; and

an upper part inwardly extending from an edge of the side part with respect to the receiving space,

wherein the cover portion is attached to the upper part.

4. The backlight assembly of claim 3, wherein the upper part covers at least a portion of the driving circuit.

5. The backlight assembly of claim 1, wherein the cover portion is attached to an inner side surface of the sidewall.

6. The backlight assembly of claim 1, wherein the sidewall comprises:

a side part upwardly extending from the edge portion of the bottom plate; and

an upper part outwardly extending from an edge of the side part with respect to the receiving space,

wherein the cover portion is attached to the upper part.

7. The backlight assembly of claim 1, wherein the cover portion extends from an end of the center portion.

8. The backlight assembly of claim 1, wherein the cover portion is separated from the center portion and attached to the upper surface of the light-emitting substrate.

9. The backlight assembly of claim 8, wherein the cover portion comprises a metal to reflect light and has a fixed shape.

10. The backlight assembly of claim 1, wherein the bottom plate has a substantially rectangular plate shape, the sidewall comprises first to fourth sidewalls respectively corresponding to first to fourth sides of the bottom plate, and the cover portion comprises first to fourth cover portions respectively corresponding to the first to fourth sidewalls.

11. The backlight assembly of claim 10, wherein the driving circuit is disposed in the peripheral region adjacent to at least one of the first to fourth sidewalls, and at least one of the first to fourth cover portions corresponding to the at least one of the first to fourth sidewalls is disposed over the peripheral region to cover the driving circuit.

12. The backlight assembly of claim 1, wherein the driving circuit is disposed in the peripheral region and electrically connected to the LEDs, and comprises a current balancer controlling the LEDs to maintain current balance of currents applied to the LEDs.

13. The backlight assembly of claim 12, further comprising a control unit electrically connected to the driving circuit to control the driving circuit.

14. The backlight assembly of claim 13, wherein the driving circuit further comprises an inner connector disposed in the peripheral region and electrically connected to the control unit by a connecting line.

15. The backlight assembly of claim 14, wherein the sidewall comprises a through-hole through which the connecting line passes.

16. A display device comprising:

a display panel displaying an image using light; and

a backlight assembly disposed under the display panel to provide the display panel with the light, the backlight assembly comprising;

a receiving container comprising a bottom plate and a sidewall upwardly extending from an edge portion of the bottom plate to form a receiving space;

a light-generating unit comprising a light-emitting substrate disposed in the receiving space, the light-emitting substrate including a light-emitting region and a peripheral region disposed outside of the light-emitting region, a plurality of LEDs disposed in the light-emitting region and a driving circuit disposed in the peripheral region, the driving circuit controlling the LEDs; and

a reflective sheet comprising a center portion disposed on the light-emitting region, the center portion including a plurality of holes through which the LEDs respectively pass and a cover portion disposed on the peripheral region to cover the driving circuit, the cover portion being attached to the sidewall.

17. The display device of claim 16, further comprising an optical member disposed between the display panel and the backlight assembly to improve optical properties of the light generated by the backlight assembly.

18. The display device of claim 17, wherein the receiving container further comprises at least one fixing protrusion protruding from an upper surface of the sidewall to fix the optical member supported by the upper surface of the sidewall.

19. The display device of claim 16, wherein the cover portion is outwardly inclined with respect to the bottom plate.

20. The display device of claim 19, wherein the sidewall comprises:

a side part upwardly extending from the edge portion of the bottom plate; and

an upper part inwardly extending from an edge of the side part with respect to the receiving space,

wherein the cover portion is attached to the upper part.