Backlight unit of liquid crystal display

• US 20050276066A1
• Filed: 08/12/2004
• Published: 12/15/2005
• Est. Priority Date: 05/28/2004
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd. (Samsung Group)
• Original Assignee: Samsung Electro-Mechanics Co., Ltd. (Samsung Group)
• Inventors: Park, Young Sam, Kim, Hyung Suk, Jeong, Young June, Hahm, Hun Joo, Park, Jung Kyu
• Granted Patent: US 7,172,325 B2
• Time in Patent Office: Days
• US Class Current: 362/561
• CPC Class Codes: G02F 1/133603 with LEDs
• CPC Class Codes: G02F 1/133605 including specially adapted reflectors
• CPC Class Codes: Y10S 362/80 Light emitting diode

Abstract

Disclosed herein is a backlight unit of a liquid crystal display. The backlight unit comprises a plurality of light emitting diode packages arranged in a matrix while being spaced a uniform distance apart from each other, each light emitting diode package including one or more light emitting diode chips and structured such that light generated from the light emitting chips is emitted in the horizontal direction, and a reflector consisting of a plurality of reflection cells connected to each other in a matrix. Each of the reflection cells of a unit size has each of the light generating packages positioned at the center thereof, and reflects the light, emitted from the light emitting diode at the center thereof in the horizontal direction, to the perpendicular direction.

Claims

1. A backlight unit of a liquid crystal display, comprising:

a plurality of light emitting diode packages arranged in a matrix while being spaced a uniform distance apart from each other, each light emitting diode package including one or more light emitting diode chips and structured such that light generated from the light emitting chips is emitted in the horizontal direction; and

a reflector consisting of a plurality of reflection cells connected to each other in a matrix, each of the reflection cells having each of the light generating packages positioned at the center of each of the reflection cells, having a unit size, and reflecting the light, emitted from the light emitting diode at the center thereof in the horizontal direction, to the perpendicular direction.

2. The backlight unit as set forth in claim 1, wherein each of the reflection cells of the reflector is formed, at the center thereof, with a hole having a predetermined size, and each of the light emitting diode packages is inserted into the hole.

3. The backlight unit as set forth in claim 1, wherein each of the light emitting diode packages comprises:

a printed circuit board with a conductive pattern for transmitting power formed thereon;

a base located on the printed circuit board and having a heat dissipation function for transmitting heat to the printed circuit board;

one or more light emitting diode chips mounted on the base and electrically connected to the conductive pattern of the printed circuit board; and

a lens formed on the base in order to change path of the light, generated from the plurality of light emitting diode chips, to the horizontal direction.

4. The backlight unit as set forth in claim 1, wherein the plurality of light emitting diode chips consists of white light emitting diodes.

5. The backlight unit as set forth in claim 1, wherein the plurality of light emitting diode chips consists of a combination of light emitting diodes emitting light of complementary colors.

6. The backlight unit as set forth in claim 3, wherein the lens comprises a reflective surface having a spherical surface shape, at an upper portion of the lens in the perpendicular direction above the plurality of light emitting diode chips, and reflecting the light emitted from the light emitting diode chips in the perpendicular direction to the lateral direction.

7. The backlight unit as set forth in claim 6, wherein the reflective surface of the lens is achieved by coating a reflective material on an upper surface of the lens after the upper surface of the lens is defined to have the spherical surface shape.

8. A backlight unit of a liquid crystal display, comprising a plurality of unit backlight cells connected to each other in a matrix, each of the plurality of unit backlight cells integrally comprising:

a printed circuit board having a conductive pattern for transmitting power formed thereon;

one or more light emitting diode chips electrically connected to the conductive pattern on the printed circuit board;

a lens for changing path of light generated from the light emitting diode chips to the horizontal direction; and

a reflector formed to surround the lens and having a unit size for reflecting the light refracted in the horizontal direction through the lens to the perpendicular direction.

9. The backlight unit as set forth in claim 8, wherein the lens comprises a reflective surface having a spherical surface shape, at an upper portion of the lens in the perpendicular direction above the plurality of light emitting diode chips, and reflecting the light emitted from the light emitting diode chips in the perpendicular direction to the lateral direction.

10. The backlight unit as set forth in claim 8, wherein the reflective surface of the lens is achieved by coating a reflective material on an upper surface of the lens after the upper surface of the lens is defined to have the spherical surface shape.

11. The backlight unit as set forth in claim 8, wherein the plurality of light emitting diode chips consists of white light emitting diodes.

12. The backlight unit as set forth in claim 8, wherein the plurality of light emitting diode chips consists of a combination of light emitting diodes emitting light of complementary colors.