Backlight device for liquid crystal display and method of fabricating the same

• US 7,460,196 B2
• Filed: 09/24/2003
• Issued: 12/02/2008
• Est. Priority Date: 09/25/2002
• Status: Expired due to Fees

• Current Assignee: LG Display Co., Ltd.
• Original Assignee: LG Display Co., Ltd.
• Inventors: Kim, Jae Bum, Yang, Seung Hoon
• Primary Examiner(s): Nguyen; Dung T.
• Application Number:
  US10/668,151
• Publication Number:
  US 20040061814A1
• Time in Patent Office: 1,896 Days
• Field of Search: 349/58, 349 61- 64, 349/65, 362/600, 362/602
• US Class Current: 349/64
• CPC Class Codes: G02B 6/0028 Light guide, e.g. taper
• CPC Class Codes: G02B 6/0031 Reflecting element, sheet or layer
• CPC Class Codes: G02B 6/0068 Arrangements of plural sources, e.g. multi-colour light sources
• CPC Class Codes: G02B 6/0086 Positioning aspects
• CPC Class Codes: G02F 1/133621 providing coloured light G02F1/133617, G02F1/133533 take precedence

Abstract

A backlight device for a liquid crystal display includes a substrate, and a plurality of white, red, green, and blue light emitting diodes arranged on the substrate.

Claims

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

a light-guiding plate disposed at a rear of a liquid crystal display panel of the liquid crystal display;

a common substrate parallel to the light-guiding plate;

a plurality of white, red, green, and blue light emitting diodes arranged on the common substrate; and

a housing to concentrate white, red, green, and blue lights emitted from the plurality of light emitting diodes along one direction, wherein the common substrate is disposed at a rear of the housing,

wherein the plurality of white, red, green, and blue light emitting diodes are sequentially disposed in an order of white, red, green, and blue, and each of the plurality of light emitting diodes has light-emitting portions disposed inside the housing and body portions disposed outside the housing such that the housing surrounds the light-emitting portions of the plurality of light emitting diodes, and

wherein upper surface and one side surface of the light-emitting portions of the plurality of light emitting diodes are opposite to the housing, and other side surface of the light-emitting portions of the plurality of light emitting diodes is opposite to a light-incidence surface of the light-guiding plate.

2. The device according to claim 1, wherein the white light emitting diodes are disposed between the blue and red light emitting diodes.

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

a light-guiding plate disposed at a rear of a liquid crystal display panel of the liquid crystal display;

a common substrate parallel to the light-guiding plate;

at least one light source disposed along one side of the light-guiding plate on the common substrate, the light source including a plurality of light emitting diodes in order of white, red, green, and blue;

a housing disposed adjacent to the light-guiding plate for concentrating white, red, green, and blue light emitted from the light source along a first light direction, wherein the common substrate is disposed at a rear of the housing; and

a reflecting plate disposed under the light-guiding plate for reflecting light leaking along a side of the liquid crystal display panel opposite to the light-guiding plate,

wherein each of the plurality of light emitting diodes has light-emitting portions disposed inside the housing and body portions disposed outside the housing such that the housing surrounds the light-emitting portions of the plurality of light emitting diodes, and

wherein upper surface and one side surface of the light-emitting portions of the plurality of light emitting diodes are opposite to the housing, and other side surface of the light-emitting portions of the plurality of light emitting diodes is opposite to a light-incidence surface of the light-guiding plate.

4. The device according to claim 3, wherein the light sources are disposed along two opposing sides of the light-guiding plate.

5. The device according to claim 3, wherein the housing includes aluminum.

6. The device according to claim 3, wherein the housing is disposed between the light-emitting portions and the body portions of the plurality of light emitting diodes.

7. A method of fabricating a backlight device for a liquid crystal display, comprising:

forming a light-guiding plate at a rear of a liquid crystal display panel of the liquid crystal display;

forming a common substrate parallel to the light-guiding plate;

forming at least one light source along one side of the light-guiding plate on the common substrate, the light source including a plurality of light emitting diodes in order of white, red, green, and blue;

forming a housing adjacent to the light-guiding plate for concentrating white, red, green, and blue light emitted from the light source along a first light direction, wherein the common substrate is disposed at a rear of the housing; and

forming a reflecting plate under the light-guiding plate for reflecting light leaking along a side of the liquid crystal display panel opposite to the light-guiding plate.

wherein each of the plurality of light emitting diodes has a portion disposed inside the housing and a portion disposed outside the housing,

wherein each of the plurality of light emitting diodes has light-emitting portions disposed inside the housing and body portions disposed outside the housing such that the housing surrounds the light-emitting portions of the plurality of light emitting diodes, and

wherein upper surface and one side surface of the light-emitting portions of the plurality of light emitting diodes are opposite to the housing, and other side surface of the light-emitting portions of the plurality of light emitting diodes is opposite to a light-incidence surface of the light-guiding plate.

8. The method according to claim 7, wherein the forming of at least one light source includes forming a plurality of the light sources along two opposing sides of the light-guiding plate.

9. The method according to claim 7, wherein the housing is disposed between the light-emitting portions and the body portions of the plurality of light emitting diodes.