BACKLIGHT UNIT AND LIQUID CRYSTAL DISPLAY DEVICE

• US 20110090422A1
• Filed: 11/04/2008
• Published: 04/21/2011
• Est. Priority Date: 03/28/2008
• Status: Active Grant

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Hamada, Tetsuya
• Granted Patent: US 8,368,843 B2
• Time in Patent Office: Days
• US Class Current: 349/62
• CPC Class Codes: G02B 6/0046 Tapered light guide, e.g. wedge-shaped light guide
• 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: G02B 6/0091 of the light source relative to the light guide G02B6/0021 takes precedence
• CPC Class Codes: G02F 1/133308 Support structures for LCD panels, e.g. frames or bezels
• CPC Class Codes: G02F 1/133322 Mechanical guidance or alignment of LCD panel support components
• CPC Class Codes: G02F 1/133615 Edge-illuminating devices, i.e. illuminating from the side

Abstract

A housing (HG) for a backlight unit (49) includes a bottom section (22), a wall section (23) and a side section (VP), and the side section (VP) is at least a part of a first groove (DH1) which sandwiches a mounting substrate (11).

Claims

1. A backlight unit, comprising:

a light emitting block;

a mounting substrate on which the light emitting block is mounted;

a light guide plate that receives light coming from the light emitting block, the light guide plate allowing the light to pass therethrough and guiding the light to an outside thereof;

a housing in which the light emitting block, the mounting substrate, and the light guide plate are housed,

wherein

the housing includes;

a bottom section that supports the light guide plate;

a wall section that rises from the bottom section; and

a protrusion section that is supported by the wall section, protrudes toward the bottom section, and extends in a direction that intersects a direction in which the wall section rises, and

the protrusion section is at least part of a first groove in which the mounting substrate is held.

2. The backlight unit of claim 1,

wherein

one of opposite inner surfaces of the first groove that face each other is formed of the protrusion section, and another one of the opposite inner surfaces of the first groove is formed of the wall section.

3. The backlight unit of claim 1,

wherein

one of the first groove is formed for one of the mounting substrate.

4. The backlight unit of claim 3,

wherein

there exist along a length of the first groove,

a first narrow groove width at which the first groove is in close contact with both a mounting surface and a non-mounting surface of the mounting substrate, and

a first wide groove width that is wider than the first narrow groove width.

5. The backlight unit of claim 4, wherein, portions of the first groove having the first narrow groove width are positioned corresponding at least to a middle portion and two end portions of the mounting substrate along a length of the mounting substrate.

6. The backlight unit of claim 1,

wherein

the first groove has a length shorter than the length of the mounting substrate,

a plurality of first grooves are formed as the first groove with respect to the mounting substrate, and

the plurality of first grooves are positioned corresponding at least to a middle portion and two end portions of the mounting substrate along a length of the mounting substrate.

7. The backlight unit of claim 1,

wherein

the protrusion section includes a reflection surface that reflects light, and

a space is formed to face at least three surfaces of the reflection surface, a light emission surface of the light emitting block, and a light reception surface of the light guide plate.

8. The backlight unit of claim 7,

wherein

an angle formed by the light emission surface of the light emitting block and the reflection surface is an acute angle, and

an angle formed by the light reception surface of the light guide plate and the reflection surface is an obtuse angle.

9. The backlight unit of claim 1,

wherein

an optical sheet that transmits light is placed so as to cover the light guide plate, and the optical sheet is held by the protrusion section.

10. The backlight unit of claim 9,

wherein

a support portion is formed in the protrusion section so as to support a liquid crystal display panel that receives light from the optical sheet.

11. The backlight unit of claim 1,

wherein

the bottom section is at least part of a second groove in which the mounting substrate is held.

12. The backlight unit of claim 11,

wherein

one of opposite inner surfaces of the second groove that face each other is formed of the bottom section, and another one of the opposite inner surfaces of the second groove is formed of the wall section.

13. The backlight unit of claim 11,

wherein

one of the second groove is formed for one of the mounting substrate.

14. The backlight unit of claim 13,

wherein

there exist along a length of the second groove,

a second narrow groove width at which the second groove is in close contact with both the mounting surface and the non-mounting surface of the mounting substrate, and

a second wide groove that is wider than the second narrow groove width.

15. The backlight unit of claim 14,

wherein,

portions of the first groove having the second narrow groove width are positioned corresponding at least to a middle portion and two end portions of the mounting substrate along a length of the mounting substrate.

16. The backlight unit of claim 11,

wherein

the first groove has a length shorter than the length of the mounting substrate,

a plurality of second grooves are formed as the second groove with respect to the mounting substrate, and

the plurality of second grooves are positioned corresponding at least to a middle portion and two end portions of the mounting substrate along a length of the mounting substrate.

17. A liquid crystal display device, comprising:

the backlight unit of claim 1; and

a liquid crystal display panel that receives light from the backlight unit.

18. The liquid crystal display device of claim 17,

wherein

an optical sheet that transmits light is placed so as to cover the light guide plate,

the optical sheet is held by the protrusion section, and

the liquid crystal display panel that receives light from the optical sheet is supported by a support portion formed in the protrusion section.