White light generating unit, backlight assembly having the same and liquid crystal display device having the same

• US 7,360,937 B2
• Filed: 09/30/2005
• Issued: 04/22/2008
• Est. Priority Date: 10/05/2004
• Status: Active Grant

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Han, Byung-Woong, Park, Young-Hee, Lee, Jong-Nam, Chu, Young-Bee, Lee, Sang-Hee, Kim, Kyu-Seok
• Primary Examiner(s): TSO, LAURA K
• Application Number:
  US11/239,819
• Publication Number:
  US 20060072315A1
• Time in Patent Office: 935 Days
• Field of Search: 362/611, 362/612, 362/613, 362/621, 362/608, 362/600, 362/84
• US Class Current: 362/608
• CPC Class Codes: G02B 6/0026 Wavelength selective element, sheet or layer, e.g. filter or grating
• CPC Class Codes: G02B 6/003 Lens or lenticular sheet or layer
• CPC Class Codes: G02B 6/0068 Arrangements of plural sources, e.g. multi-colour light sources
• CPC Class Codes: G02B 6/0073 Light emitting diode [LED]
• CPC Class Codes: G02B 6/009 of the light source in the package G02B6/0021 takes precedence
• CPC Class Codes: G02F 1/133603 with LEDs
• CPC Class Codes: H01L 33/505 characterised by the shape, e.g. plate or foil
• CPC Class Codes: H01L 33/507 the elements being in intimate contact with parts other than the semiconductor body or integrated with parts other than the semiconductor body
• CPC Class Codes: H01L 33/58 Optical field-shaping elements

Abstract

A white light generating unit includes an LED structure and a lens structure. The LED structure generates a light. The lens structure has a convex lens or a concave lens. The lens structure has a fluorescent member that receives the light from the LED structure to emit a white light.

Claims

1. A white light generating unit comprising:

a light emitting diode (LED) structure generating a light; and

a lens structure having a fluorescent member that generates a white light after receiving the light from the LED structure, the lens structure being separably assembled with the LED structure.

2. The white light generating unit of claim 1, wherein the LED structure comprises a blue LED.

3. The white light generating unit of claim 2, wherein the fluorescent member comprises a yellow fluorescent material.

4. The white light generating unit of claim 2, wherein the fluorescent member comprises a red fluorescent material and a green fluorescent material.

5. The white light generating unit of claim 1, wherein the LED structure comprises an ultraviolet (UV) LED.

6. The white light generating unit of claim 5, wherein the fluorescent member comprises a red fluorescent material, a green fluorescent material and a blue fluorescent material.

7. The white light generating unit of claim 1, wherein the lens structure comprises a convex lens.

8. The white light generating unit of claim 1, wherein the lens structure comprises a concave lens.

9. The white light generating unit of claim 1, wherein the lens structure comprises a diffusing agent that diffuses the light generated from the LED structure.

10. The white light generating unit of claim 9, wherein the diffusing agent is in the form of a powder.

11. The white light generating unit of claim 10, wherein the diffusing agent includes at least one of stone powder and an acryl resin.

12. The white light generating unit of claim 1, wherein the fluorescent member is in the form of a powder.

13. The white light generating unit of claim 12, wherein the lens structure comprises a curing agent that hardens the fluorescent member.

14. The white light generating unit of claim 1, further comprising a reflective band disposed on at least one face of the lens structure to reflect a light deviated from the lens structure back to the lens structure.

15. A backlight assembly, comprising:

a light generating unit including an LED structure having at least one LED that generates a light;

a light guiding plate that guides the light emitted from the light generating unit and emits the light;

a lens structure having at least one lens disposed between the light generating unit and the light guiding plate, and the lens structure having a fluorescent member that receives the light from the light generating unit to emit a white light and being separably assembled with the LED structure; and

a receiving container that receives the light generating unit, the light guiding plate, and the lens structure.

16. The backlight assembly of claim 15, wherein the LED structure comprises a blue LED and the fluorescent member comprises a yellow fluorescent material.

17. The backlight assembly of claim 15, wherein the LED structure comprises a blue LED and the fluorescent member comprises a red fluorescent material and a green fluorescent material.

18. The backlight assembly of claim 15, wherein the LED structure comprises a UV LED and the fluorescent member comprises a red fluorescent material, a green fluorescent material and a blue fluorescent material.

19. The backlight assembly of claim 15, wherein the lens structure comprises one of a convex lens and a concave lens.

20. The backlight assembly of claim 15, further comprising a reflective band disposed on at least one face of the lens structure to reflect a light deviated from the lens structure back into the lens structure.

21. The backlight assembly of claim 15, wherein the lens structure comprises a diffusing agent that diffuses the light provided from the light generating unit.

22. The backlight assembly of claim 21, wherein the lens structure further comprises a curing agent that hardens the diffusing agent.

23. The backlight assembly of claim 15, further comprising a receiving groove formed on a side portion of the light guide plate to receive the lens structure.

24. The backlight assembly of claim 23, wherein the receiving groove has a shape corresponding to that of the lens structure.

25. The backlight assembly of claim 24, wherein the lens structure makes contact with the receiving groove.

26. The backlight assembly of claim 23, wherein the lens structure is spaced apart from the receiving groove.

27. A liquid crystal display (LCD) device, comprising:

a backlight assembly comprising;

a light generating unit including an LED structure having at least one LED that generates a light;

a light guiding plate that guides the light emitted from the light generating unit and emits the light;

a lens structure having at least one lens disposed between the light generating unit and the light guiding plate and the lens structure having a fluorescent member that receives the light from the light generating unit to emit a white light and being separably assembled with the LED structure; and

a receiving container that receives the light generating unit, the light guiding plate, and the lens structure; and

an LCD panel that receives the light to display an image.

28. The LCD device of claim 27, wherein the LED structure comprises a blue LED, and the fluorescent member comprises a yellow fluorescent material.

29. The LCD device of claim 27, wherein the LED structure comprises a blue LED, and the fluorescent member comprises a red fluorescent material and a green fluorescent material.

30. The LCD device of claim 27, wherein the LED structure comprises a UV LED, and the fluorescent member comprises a red fluorescent material, a green fluorescent material and a blue fluorescent material.

31. The LCD device of claim 27, wherein the lens structure comprises one of a convex lens and a concave lens.