Liquid crystal display device having improved cooling efficiency

• US 10,162,217 B2
• Filed: 04/15/2014
• Issued: 12/25/2018
• Est. Priority Date: 06/13/2005
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Sung Ki, Kim, Won-nyun, Kim
• Primary Examiner(s): Nguyen, Lauren
• Application Number:
  US14/253,456
• Publication Number:
  US 20140226106A1
• Time in Patent Office: 1,715 Days
• Field of Search: 349 58
• CPC Class Codes: G02B 6/0051 Diffusing sheet or layer
• CPC Class Codes: G02B 6/0053 Prismatic sheet or layer; Brightness enhancement element, sheet or layer
• CPC Class Codes: G02B 6/0055 Reflecting element, sheet or layer
• CPC Class Codes: G02B 6/0085 Means for removing heat created by the light source from the package heat extraction or cooling elements for semiconductor light sources in general H01L33/64
• CPC Class Codes: G02F 1/133382 Heating or cooling of liquid crystal cells other than for activation, e.g. circuits or arrangements for temperature control, stabilisation or uniform distribution over the cell
• CPC Class Codes: G02F 1/133603 with LEDs
• CPC Class Codes: G02F 1/133628 with cooling means

Abstract

A liquid crystal display device includes a liquid crystal display panel, a light guide plate disposed on a lower part of the liquid crystal display panel, an LED circuit substrate disposed along at least one side of the light guide plate to accommodate an LED on a front surface thereof, and a heat transmission member having a first part that faces a lower surface of the light guide plate and a second part that is extendedly bent from the first part and faces the LED circuit substrate.

Claims

1. A liquid crystal display device, comprising:

a liquid crystal display panel;

a plurality of light emitting diodes (LEDs) on a circuit substrate to emit light in a direction toward an end of a light guide plate;

an inner heat transmission member to support the circuit substrate and the light guide plate;

an outer heat transmission member to house the inner heat transmission member;

a bottom reflection element disposed between the light guide plate and the inner heat transmission member to reflect the light toward the liquid crystal display panel through the light guide plate; and

a top reflection element disposed adjacent to the plurality of LEDs and on a portion of a top surface of the light guide plate, the plurality of LEDs being between the top reflection element and the inner heat transmission member,

wherein the inner heat transmission member is configured to distribute heat from the plurality of LEDs,

wherein the top reflection element and the bottom reflection element comprise a same material,

wherein the inner heat transmission member and the top reflection element comprise a different material from each other,

wherein the inner heat transmission member accommodates the bottom reflection element, and

wherein the circuit substrate is disposed between the plurality of LEDs and the inner heat transmission member such that a surface of the inner heat transmission member faces a back surface of the plurality of LEDs, the back surface of the plurality of LEDs being on an opposite side of the direction toward which light emits from the plurality of LEDs.

2. The liquid crystal display device of claim 1, wherein a surface area of the inner heat transmission member faces a surface area of the bottom reflection element.

3. The liquid crystal display device of claim 1, wherein a surface area of the inner heat transmission member directly contacts a surface area of the bottom reflection element.

4. The liquid crystal display device of claim 1, wherein the outer heat transmission member is configured to distribute heat from an inside of the liquid crystal display device and discharge the heat to an outside of the liquid crystal display device.

5. The liquid crystal display device of claim 1, wherein the outer heat transmission member contacts the inner heat transmission member.

6. The liquid crystal display device of claim 1, wherein a size of the light guide plate is substantially the same as a size of the bottom reflection element.

7. The liquid crystal display device of claim 1, wherein the top reflection element is a strip type.

8. The liquid crystal display device of claim 7, wherein a portion of the top reflection element is disposed between the liquid crystal display panel and the light guide plate.

9. The liquid crystal display device of claim 1, wherein the circuit substrate is disposed between the light guide plate and the inner heat transmission member.

10. The liquid crystal display device of claim 1, wherein the heat is transferred away from the circuit substrate to the inner heat transmission member and the outer heat transmission member.

11. The liquid crystal display device of claim 1, wherein the bottom reflection element and the top reflection element are connected via a middle reflection element having a plurality of holes formed therein to accommodate the plurality of LEDs.

12. The liquid crystal display device of claim 1, wherein the circuit substrate comprises heat transmission material.

13. The liquid crystal display device of claim 12, wherein the heat transmission material is metal.

14. The liquid crystal display device of claim 1, wherein the outer heat transmission member is made of graphite.

15. The liquid crystal display device of claim 1, wherein a heat transmission of the outer heat transmission member is larger than a heat transmission of the inner heat transmission member.

16. The liquid crystal display device of claim 1, wherein a surface of the circuit substrate is perpendicular to a bottom surface of the light guide plate.

17. The liquid crystal display device of claim 1, further comprising:

a gap pad disposed between the circuit substrate and the inner heat transmission member.

18. The liquid crystal display device of claim 1, wherein the LEDs and the light guide plate are spaced at a predetermined interval.

20. The liquid crystal display device of claim 1, wherein the outer heat transmission member is configured to distribute heat from an inside of the liquid crystal display device.

23. The liquid crystal display device of claim 1, wherein the outer heat transmission member is made of graphite.

26. The liquid crystal display device of claim 1, wherein the top reflection element and the bottom reflection element are integral with each other.

27. The liquid crystal display device of claim 1, wherein a surface of a surface area of the inner heat transmission member is disposed on a side of the plurality of LEDs opposite the direction.

28. The liquid crystal display device of claim 1, wherein the inner heat transmission member comprises metal.

19. A liquid crystal display device, comprising:

a liquid crystal display panel;

a plurality of light emitting diodes (LEDs) on a circuit substrate to emit light in a direction toward an end of a light guide plate;

an inner heat transmission member configured to support the circuit substrate and the light guide plate;

an outer heat transmission member to house the inner heat transmission member;

a bottom reflection element disposed between the light guide plate and the inner heat transmission member to reflect the light toward the liquid crystal display panel through the light guide plate; and

a top reflection element disposed adjacent to the plurality of LEDs and on a portion of a top surface of the light guide plate to reflect the light from the plurality of LEDs toward the bottom reflection element, the plurality of LEDs being between the top reflection element and the inner heat transmission member,

wherein the top reflection element is a strip type which is provided along with an edge of the top surface of the light guide plate,

wherein the inner heat transmission member is configured to distribute heat from the plurality of LEDs,

wherein the top reflection element and the bottom reflection element comprise a same material,

wherein the inner heat transmission member and the top reflection element comprise a different material from each other,

wherein the inner heat transmission member accommodates the bottom reflection element, and

wherein the circuit substrate is disposed between the plurality of LEDs and the inner heat transmission member such that a surface of the inner heat transmission member faces a back surface of the plurality of LEDs, the back surface of the plurality of LEDs being on an opposite side of the direction toward which light emits from the plurality of LEDs.

21. The liquid crystal display device of claim 19, wherein the bottom reflection element and the top reflection element are connected via a middle reflection element having a plurality of holes formed therein to accommodate the plurality of LEDs.

22. The liquid crystal display device of claim 19, wherein the circuit substrate is made of metal.

24. The liquid crystal display device of claim 19, wherein a surface of the circuit substrate is perpendicular to a bottom surface of the light guide plate.

25. The liquid crystal display device of claim 19, wherein the LEDs and the light guide plate are spaced at a predetermined interval.

29. A liquid crystal display device, comprising:

a liquid crystal display panel;

a plurality of light emitting diodes (LEDs) on a circuit substrate to emit light in a direction toward an end of a light guide plate;

a first member to support the circuit substrate and the light guide plate;

a second member to house the first member;

a bottom reflection element disposed between the light guide plate and the first member to reflect the light toward the liquid crystal display panel through the light guide plate; and

a top reflection element disposed adjacent to the plurality of LEDs and on a portion of a top surface of the light guide plate, the plurality of LEDs being between the top reflection element and the first member,

wherein the first member is configured to transmit heat from the plurality of LEDs,

wherein the second member is configured to transmit heat from the first member,

wherein the top reflection element and the bottom reflection element comprise a same material, and

wherein the first member and the top reflection element comprise a different material from each other,

wherein the first member accommodates the bottom reflection element, and

wherein the circuit substrate is disposed between the plurality of LEDs and the first member such that a surface of the first member faces a back surface of the plurality of LEDs, the back surface of the plurality of LEDs being on an opposite side of the direction toward which light emits from the plurality of LEDs.

30. The liquid crystal display device of claim 29, wherein the second member is configured to transmit the heat from the first member to an outside of the liquid crystal display device.

31. The liquid crystal display device of claim 29, wherein the second member directly contacts the first member.

32. The liquid crystal display device of claim 29, wherein the first member and the second member are configured to transmit heat from the circuit substrate.

33. The liquid crystal display device of claim 29, wherein a heat transmission of the second member is larger than a heat transmission of the first member.

34. The liquid crystal display device of claim 29, wherein the first member comprises metal.

35. The liquid crystal display device of claim 29, wherein the second member comprises graphite.

36. The liquid crystal display device of claim 29, wherein the circuit substrate is disposed between the light guide plate and the first member.

37. The liquid crystal display device of claim 29, wherein a surface of the circuit substrate is perpendicular to a bottom surface of the light guide plate.

38. The liquid crystal display device of claim 29, wherein the circuit substrate comprises metal.

39. The liquid crystal display device of claim 29, wherein a portion of the top reflection element is disposed between the liquid crystal display panel and the light guide plate.

40. The liquid crystal display device of claim 29, wherein the top reflection element is a strip type.

41. The liquid crystal display device of claim 29, wherein the top reflection element and the bottom reflection element are connected via a middle reflection element having a plurality of holes formed therein to accommodate the plurality of LEDs.

42. The liquid crystal display device of claim 29, wherein the top reflection element and the bottom reflection element are integral with each other.

43. The liquid crystal display device of claim 29, wherein a portion of a surface area of the first member is disposed on a side of the plurality of LEDs opposite the direction.

44. The liquid crystal display device of claim 29, wherein a size of the light guide plate is substantially the same as a size of the bottom reflection element.

45. The liquid crystal display device of claim 29, wherein the second member comprises metal.

46. The liquid crystal display device of claim 29, wherein a surface area of the first member is larger than a surface area of the bottom reflection element.

47. The liquid crystal display device of claim 29, wherein the first member is configured to transmit the heat from the plurality of LEDs the circuit substrate.

48. The liquid crystal display device of claim 29, wherein the second member is configured to transmit the heat from the plurality of LEDs through the first member.