DIRECT-TYPE BACKLIGHT UNIT FOR FLAT PANEL LIQUID CRYSTAL DISPLAYS

• US 20040032725A1
• Filed: 04/22/2003
• Published: 02/19/2004
• Est. Priority Date: 08/16/2002
• Status: Active Grant

• Current Assignee: AU Optronics Corporation
• Original Assignee: AU Optronics Corporation
• Inventors: Yu, Chuan-Pei, Liu, Han-Chou, Hsieh, Chin-Kun
• Granted Patent: US 6,880,947 B2
• Time in Patent Office: Days
• US Class Current: 362/31
• CPC Class Codes: G02F 1/133604 with lamps
• CPC Class Codes: G02F 1/133628 with cooling means
• CPC Class Codes: G02F 2201/36 Airflow channels, e.g. constructional arrangements facilitating the flow of air

Abstract

A direct-type backlight unit for a flat panel liquid crystal display includesat least one lamp installed in a housing, a diffusion plate installed above the lamp, a reflection plate having a reflection surface and a back surface installed under the lamp for reflecting light generated by the lamp from the reflection surface to the diffusion plate, and the reflection plate having at least one aperture thereon, and a heat dissipating plate combined with the back surface of the reflection plate.

Claims

1. A direct-type backlight unit for a flat panel liquid crystal display, comprising:

at least one lamp installed in a housing;

a diffusion plate installed above the lamp;

a reflection plate having a reflection surface and a back surface installed under the lamp for reflecting light generated by the lamp from the reflection surface to the diffusion plate, and the reflection plate having at least one aperture thereon; and

a heat dissipating plate combined with the back surface of the reflection plate.

2. The direct-type backlight unit of claim 1, wherein the lamp is a cold cathode fluorescent lamp (CCFL).

3. The direct-type backlight unit of claim 1, wherein the aperture is located directly below the lamp.

4. The direct-type backlight unit of claim 1, wherein the aperture is a through slot corresponding to the length of the lamp.

5. The direct-type backlight unit of claim 4, wherein the lamp is a cylindrical fluorescent lamp and the through slot has a slot width that is less than half of the diameter of the lamp.

6. The direct-type backlight unit of claim 1, wherein the heat dissipating plate and the back surface of the reflection plate define a chamber communicating the aperture.

7. The direct-type backlight unit of claim 1, wherein the heat dissipating plate is attached to the back surface of the reflection plate.

8. The direct-type backlight unit of claim 1, wherein the heat dissipating plate is combined with the housing and are together pressed into a fin type heat dissipating structure.

9. The direct-type backlight unit of claim 1, wherein the heat dissipating plate is attached to an inner surface of the housing and on an outer surface of the housing there is provided a fin-type heat dissipating film.

10. The direct-type backlight unit of claim 1, wherein the heat dissipating plate is made of copper or aluminum.

11. A direct-type backlight unit for a flat panel liquid crystal display, comprising:

a diffusion plate;

a reflection plate having a bottom surface and inclined side surface, a first convection opening being formed at the bottom surface, and the reflection plate and the diffusion plate defining a first chamber;

at least one lamp installed within the first chamber directly above the first convection opening; and

at least one heat dissipating plate, the heat dissipating plate and the reflection plate defining a second chamber communicating the first convection opening, such that heat generated by the lamp can be transferred to the heat dissipating plate by means of convection occurred in the first chamber and second chamber thereby elongating lifetime of the lamp.

12. The direct-type backlight unit of claim 11, wherein a second convection opening is formed on the inclined side surface of the reflection plate and the second convection opening communicates with the second chamber.

13. The direct-type backlight unit of claim 11, wherein the lamp is a cylindrical cold cathode fluorescent lamp (CCFL).

14. The direct-type backlight unit of claim 11, wherein the first convection opening is a through slot laid on the reflection plate corresponding the length of the lamp.

15. The direct-type backlight unit of claim 14, wherein the through slot has a slot width less than half of the diameter of the lamp.

16. The direct-type backlight unit of claim 11, wherein the heat dissipating plate is combined with a housing and are together pressed into a fin type heat dissipating structure.

17. The direct-type backlight unit of claim 16, wherein the heat dissipating plate is attached to an inner surface of the housing and on an outer surface of the housing there is provided a fin-type heat dissipating film.

18. The direct-type backlight unit of claim 11, wherein the heat dissipating plate is made of copper or aluminum.

19. The direct-type backlight unit of claim 11, further comprising a sealing film blocking the first convection opening and sealing the second chamber which is substantially filled with liquid or solid heat conducting material.