Reflective plate and method for manufacturing the same and backlight unit for liquid crystal display device using the same

• US 20070053205A1
• Filed: 08/30/2006
• Published: 03/08/2007
• Est. Priority Date: 08/30/2005
• Status: Active Grant

• Current Assignee: LG Display Co., Ltd.
• Original Assignee: LG Philips LCD Company Limited (LG Display Co., Ltd.)
• Inventors: Kim, Tae, Kim, Gi, Jang, Myong
• Granted Patent: US 8,480,282 B2
• Time in Patent Office: Days
• US Class Current: 362/609
• CPC Class Codes: F21S 4/10 with light sources attached to loose electric cables, e.g. Christmas tree lights
• CPC Class Codes: F21V 27/00 Cable-stowing arrangements structurally associated with lighting devices, e.g. reels storing lengths of cable in general B65H; the lighting devices being vehicle headlamps F21S41/192; the lighting devices being vehicle lights F21S43/195
• CPC Class Codes: F21W 2121/04 for Christmas trees
• CPC Class Codes: F21Y 2101/00 Point-like light sources
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: G02B 6/0055 Reflecting element, sheet or layer
• CPC Class Codes: G02F 1/133605 including specially adapted reflectors
• CPC Class Codes: Y10T 156/10 Methods of surface bonding and/or assembly therefor

Abstract

A reflective plate includes a high heat conductivity material having a first heat conductivity and a reflective material having a second heat conductivity on the high heat conductivity material, wherein the first heat conductivity of the high heat conductivity material is greater than the second heat conductivity of the reflective material.

Claims

1. A reflective plate, comprising:

a high heat conductivity material having a first heat conductivity; and

a reflective material having a second heat conductivity on the high heat conductivity material, wherein the first heat conductivity of the high heat conductivity material is greater than the second heat conductivity of the reflective material.

2. The reflective plate of claim 1, wherein the high heat conductivity material includes at least one of graphite, aluminum, copper, carbon nano tube, and AlSiC in one of sheet, plate or powder form.

3. The reflective plate of claim 1, wherein the reflective material includes at least one of Ag, Al₂O₃, TiO₂, Al, Polyethylene Terephthalate, and optical fiber.

4. The reflective plate of claim 1, wherein the reflective material is formed by one of plasma vapor deposition, sputtering, laminating, and coating.

5. The reflective plate of claim 1, wherein the high heat conductivity material has a first thickness smaller than a second thickness of the reflective material.

6. The reflective plate of claim 1, further comprising a buffer layer for covering side and back surfaces of the high heat conductivity material.

7. A method for manufacturing a reflective plate, comprising:

providing a heat dissipation plate of high heat conductivity material having a first heat conductivity; and

forming a reflective material having a second heat conductivity on the high heat conductivity material,

wherein the first heat conductivity is greater than the second heat conductivity.

8. The method for manufacturing a reflective plate of claim 7, wherein the reflective material is formed by one of plasma vapor deposition and sputtering.

9. The method for manufacturing a reflective plate of claim 7, wherein the reflective material includes at least one of Ag, Al₂O₃, TiO₂, Al, Polyethylene Terephthalate, and optical fiber.

10. A method for manufacturing a reflective plate, comprising:

providing a heat dissipation base;

placing a heat dissipation plate of high heat conductivity material having a first heat conductivity on the heat dissipation base; and

placing a reflective material having a second heat conductivity on the high heat conductivity material, wherein the first heat conductivity is greater than the second heat conductivity.

11. The method for manufacturing a reflective plate of claim 10, wherein the high heat conductivity material is placed by one of laminating and coating.

12. The method for manufacturing a reflective plate of claim 10, wherein the high heat conductivity material includes at least one of graphite, aluminum, copper, carbon nano tube, and AlSiC in one of sheet, plate and powder form.

13. A backlight unit comprising:

a lamp for emitting light;

a light plate for distributing the light from the lamp into a planar light and directing the planar light to a liquid crystal display panel;

a lamp housing for reflecting the light from the lamp onto a light incident surface at an edge of the light plate;

a reflective plate having a stack of a high heat conductivity material with a first heat conductivity and a reflective material having a second heat conductivity on a back side of the light plate; and

a bottom cover for supporting the lamp housing and the light plate,

wherein the first heat conductivity is greater than the second heat conductivity.

14. The backlight unit of claim 13, further comprising an optical sheet on the light plate.

15. The backlight unit of claim 13, wherein the reflective plate extends to an upper surface of the light plate at an edge of the light plate opposite to the light incident surface of the light plate.

16. The backlight unit of claim 13, wherein the lamp includes one of light emitting diodes and a fluorescent lamp.

17. The backlight unit of claim 13, wherein the reflective material includes at least one of Ag, Al₂O₃, TiO₂, Al, Polyethylene Terephthalate, and optical fiber.

18. The backlight unit of claim 13, wherein the high heat conductivity material includes at least one of graphite, aluminum, copper, carbon nano tube, and AlSiC in one of sheet, plate and powder form.

19. A backlight unit comprising:

a plurality of lamps for emitting light;

a cover bottom for supporting and receiving the plurality of lamps;

an optical sheet for covering an upper surface of the bottom cover and diffusing the light from the plurality of lamps; and

a reflective plate having a stack of a high heat conductivity material with a first heat conductivity and a reflective material with a second heat conductivity on an inside surface of the bottom cover for reflecting the light from the plurality of lamps toward the optical sheet,

wherein the first heat conductivity is greater than the second heat conductivity.

20. A liquid crystal display device comprising:

a liquid crystal display panel for displaying a picture;

a lamp for emitting light;

a light plate for distributing the light from the lamp into a planar light and directing the planar light to a liquid crystal display panel;

a lamp housing for reflecting the light from the lamp onto a light incident surface at an edge of the light plate;

a reflective plate having a stack of high heat conductivity material with a first heat conductivity and a reflective material having a second heat conductivity on a back side of the light plate; and

a bottom cover for supporting the lamp housing and the light plate,

wherein the first heat conductivity is greater than the second heat conductivity.

21. A liquid crystal display device comprising:

a plurality of lamps for emitting light;

a cover bottom for supporting and receiving the plurality of lamps;

an optical sheet for covering an upper surface of the bottom cover and diffusing the light from the plurality of lamps; and

a reflective plate having a stack of a high heat conductivity material with a first heat conductivity and a reflective material with a second heat conductivity on an inside surface of the bottom cover for reflecting the light from the plurality of lamps toward the optical sheet, wherein the first heat conductivity is greater than the second heat conductivity; and

a liquid crystal display panel over the optical sheet for receiving the light through the optical sheet to display a picture.