Light Unit and Liquid Crystal Display Device Having the Same

• US 20080316750A1
• Filed: 07/31/2007
• Published: 12/25/2008
• Est. Priority Date: 08/11/2006
• Status: Active Grant

• Current Assignee: Suzhou Lekin Semiconductor Company Limited
• Original Assignee: LG Innotek Company Limited (LG Corporation)
• Inventors: Park, Jun Seok
• Granted Patent: US 8,057,057 B2
• Time in Patent Office: Days
• US Class Current: 362/294
• CPC Class Codes: G02F 1/133603 with LEDs
• CPC Class Codes: G02F 1/133609 including means for improving the color mixing, e.g. white
• CPC Class Codes: H05K 1/142 Arrangements of planar printed circuit boards in the same plane, e.g. auxiliary printed circuit insert mounted in a main printed circuit

Abstract

Provided are a light unit and a liquid crystal display (LCD) having the same. The light unit comprises a housing; at least one first printed circuit board (PCB) arranged in the housing in a first direction; at least one second PCB arranged in the housing in a direction opposite to the first direction; and light emitting diodes mounted on the first and second PCBs.

Claims

1. A light unit, comprising:

a housing;

at least one first printed circuit board arranged in the housing in a first direction;

at least one second printed circuit board arranged in the housing in a direction opposite to the first direction; and

light emitting diodes mounted on the first and second printed circuit boards.

2. The light unit according to claim 1, wherein the first and second printed circuit boards are arranged such that they alternate each other in singularity or plurality.

3. The light unit according to claim 1, wherein the first printed circuit board or the second printed circuit board is selectively disposed in a middle region, and upper and lower regions of the housing.

4. The light unit according to claim 1, comprising connectors for external connection, provided on ends of the first and second printed circuit boards.

5. The light unit according to claim 1, wherein the light emitting diode comprises at least one of a red light emitting diode chip, a green light emitting diode chip and a blue light emitting diode chip.

6. The light unit according to claim 1, wherein the light emitting diode mounted on the first printed circuit board is arranged in a direction opposite to the light emitting diode mounted on the second printed circuit board or has a brightness distribution different from the light emitting diode mounted on the second printed circuit board.

7. The light unit according to claim 1, comprising a heatsink member provided on at least one of a base, a rear surface and a side surface of the housing, wherein the heatsink member comprises at least one of a heatsink sheet, a heatsink plate and a heatsink bar.

8. The light unit according to claim 1, wherein the housing has a shape of a rectangular frame, and an outer side of the housing is inclined at a predetermined angle with respect to a base of the housing for reflecting leakage light.

9. The light unit according to claim 1, wherein each of the first and second printed circuit boards comprises a plurality of light emitting diode bars connected in series,

at least one printed circuit board of the plurality of light emitting diode bars being arranged in a first direction or an opposite direction to the first direction.

10. A light unit, comprising:

a housing comprising a heatsink member;

a plurality of printed circuit boards disposed in the housing; and

light emitting diodes mounted on the printed circuit boards.

11. The light unit according to claim 10, wherein at least one of the printed circuit boards is arranged in a direction opposite to another printed circuit board.

12. The light unit according to claim 10, wherein the heatsink member comprises at least one of a heatsink sheet, a heatsink plate and a heatsink bar, which is provided on at least one of a base, a rear surface and a side surface of the housing.

13. The light unit according to claim 10, wherein the printed circuit board comprises a first printed circuit board and a second printed circuit board,

wherein a light emitting diode mounted on the first printed circuit board is arranged in a direction opposite to the light emitting diode mounted on the second printed circuit board or has a bright distribution different from the light emitting diode mounted on the second printed circuit board.

14. The light unit according to claim 12, wherein the heatsink bar is integrally formed with or formed separately and coupled to the housing, the heatsink bar having at least one shape of a stripe type right-angled triangle or a rectangle in a vertical direction.

15. The light unit according to claim 12, wherein a surface of the heatsink bar is anodized.

16. The light unit according to claim 10, comprising a light emitting diode driver and a liquid crystal panel driver disposed on a portion of a rear surface of the housing.

17. A liquid crystal display, comprising:

a liquid crystal panel; and

a light unit provided under the liquid crystal panel, and supplying light,

wherein the light unit comprises;

a housing;

at least one first printed circuit board arranged in the housing in a first direction;

at least one second printed circuit board arranged in the housing in a direction opposite to the first direction; and

light emitting diodes mounted on the first and second printed circuit boards.

18. The liquid crystal display according to claim 17, wherein the light unit comprises a diffusion sheet and a prism sheet disposed on the light emitting diode.

19. The liquid crystal display according to claim 17, wherein the light unit comprises at least one of a heatsink sheet, a heatsink plate, a semiconductor heatsink element, a heatsink fin, and a heatsink bar, which is provided on the housing.

20. The liquid crystal display according to claim 19, wherein the heatsink bar is provided on a rear surface of the housing, and the heatsink bar has a greater area in an upper portion of the housing than a lower portion.