Direct type backlight assembly and liquid crystal display device having the same

• US 7,832,893 B2
• Filed: 05/27/2005
• Issued: 11/16/2010
• Est. Priority Date: 05/31/2004
• Status: Active Grant

• Current Assignee: LG Display Co., Ltd.
• Original Assignee: LG Display Co., Ltd.
• Inventors: Moon, Jeong Min
• Primary Examiner(s): Sember; Thomas M
• Application Number:
  US11/138,692
• Publication Number:
  US 20050265045A1
• Time in Patent Office: 1,999 Days
• Field of Search: 362/611, 362/612, 362/613, 362/614, 362/615, 362/561, 362/606, 362/610, 362/255, 362/236, 362/240, 362/560, 362/228, 362/235, 362/294, 362/245, 362 971- 974, 362241-248, 362/27, 362/330, 362326-329, 362600-634, 362223-225, 362/260, 36221708-21709, 349/62, 349/68, 349 61- 65, 385/146
• US Class Current: 362/225
• CPC Class Codes: G02F 1/133604 with lamps
• CPC Class Codes: G02F 1/133606 including a specially adapted diffusing, scattering or light controlling members

Abstract

A backlight assembly for a liquid crystal display device includes a plurality of lamps spaced apart from one another, a bottom cover accommodating the plurality of lamps, a reflection sheet below the plurality of lamps, and an auxiliary optical unit covering the plurality of lamps to adjust a traveling path of light emitted from the plurality of lamps.

Claims

1. A backlight assembly for a liquid crystal display device, comprising:

a plurality of lamps extending along a direction and spaced apart from one another;

a bottom cover accommodating the plurality of lamps;

a reflection sheet below the plurality of lamps;

a plurality of auxiliary optical elements having a long, bar-like shape, each arranged in parallel to cover at least one of the plurality of lamps extending along the direction to adjust a traveling path of light emitted from the at least one lamps, wherein each auxiliary optical element has an upper surface having a recession region corresponding to the at least one lamp at a center area and a round region at the remaining area; and

a diffusion pattern directly on and corresponding to a surface of the recession region of the auxiliary optical element,

wherein each of the auxiliary optical elements is spaced apart from one another,

wherein light from the lamp is diffused toward a front direction by the auxiliary optical element,

wherein the upper surface of the auxiliary optical element has wholly the same height and the recession region is formed of the groove correspond to the lamp, and

wherein the recession region is lower than the height of the upper surface.

2. The backlight assembly according to claim 1, wherein the auxiliary optical element has a lens shape.

3. The backlight assembly according to claim 1, further comprising a diffuser plate and a diffuser sheet on the auxiliary optical element.

4. The backlight assembly according to claim 1, wherein the plurality of lamps include one of a fluorescent lamp and a light emitting diode array.

5. The backlight assembly according to claim 1, wherein the adjusted light path is substantially uniform.

6. The backlight assembly according to claim 1, wherein the backlight assembly is a direct type.

7. The backlight assembly for a liquid crystal display device according to claim 1, wherein each of the plurality of auxiliary optical elements covers at least two of the plurality of lamps.

8. A liquid crystal display device comprising:

a backlight assembly including a plurality of lamps extending along a direction and spaced apart from one another, a bottom cover accommodating the lamps, a reflection sheet below the lamps, and a plurality of auxiliary optical elements having a long, bar-like shape, each arranged in parallel to cover at least one of the lamps extending along the direction to change a traveling path of light emitted from the lamps, wherein each auxiliary optical element has an upper surface having a recession region corresponding to the at least one lamp at a center area and a round region at the remaining area; and

a liquid crystal display panel on the backlight assembly to display an image,

a diffusion pattern directly on and corresponding to a surface of the recession region of the auxiliary optical element,

wherein each of the auxiliary optical elements is spaced apart from one another,

wherein light from the lamp is diffused toward a front direction by the auxiliary optical element,

wherein the upper surface of the auxiliary optical element has wholly the same height and the recession region is formed of the groove correspond to the lamp, and

wherein the recession region is lower than the height of the upper surface.

9. The device according to claim 8, wherein the auxiliary optical element has a lens shape.

10. The device according to claim 8, further comprising a diffuser plate and a diffuser sheet on the auxiliary optical element.

11. The device according to claim 8, wherein the plurality of lamps includes one of a fluorescent lamp and a light emitting diode array.

12. The device according to claim 8, wherein the backlight assembly is a direct type.

13. The device according to claim 8, wherein the changed light path is substantially uniform.

14. The liquid crystal display device according to claim 8, wherein each of the plurality of auxiliary optical elements covers at least two of the plurality of lamps.