Backlight unit using light emitting diode

• US 20070236447A1
• Filed: 04/06/2007
• Published: 10/11/2007
• Est. Priority Date: 04/07/2006
• Status: Abandoned Application

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electro-Mechanics Co., Ltd. (Samsung Group)
• Inventors: Lee, Sang Yun, Kim, Hyung Suk
• Application Number:
  US11/783,130
• Publication Number:
  US 20070236447A1
• Time in Patent Office: Days
• US Class Current: 345/102
• CPC Class Codes: G09G 2320/0233 Improving the luminance or brightness uniformity across the screen
• CPC Class Codes: G09G 2330/021 Power management, e.g. power saving
• CPC Class Codes: G09G 3/3413 Details of control of colour illumination sources
• CPC Class Codes: H05B 45/20 Controlling the colour of the light

Abstract

A backlight unit using LEDs in which a plurality of LEDs of different colors used for a surface light source are connected in an electric connection structure incorporating series and parallel connections so that the LEDs of the same color are driven by a single driving circuit, thereby improving the driving efficiency of LEDs. The backlight unit includes a plurality of LED modules each having a plurality of red LEDs, a plurality of green LEDs, and a plurality of blue LEDs electrically connected, respectively. The backlight unit also includes an LED driver composed of a red LED driving circuit, a green LED driving circuit, and a blue LED driving circuit for driving each color group of the plurality of LEDs provided in the LED modules. The plurality of red LEDs, the plurality of green LEDs, and the plurality of blue LEDs in the respective LED modules are electrically connected, respectively.

Claims

1. A backlight unit using Light Emitting Diodes (LEDs) comprising:

a plurality of LED modules each comprising a plurality of red LEDs electrically connected to each other, a plurality of green LEDs electrically connected to each other, and a plurality of blue LEDs electrically connected to each other;

an LED driver comprising a red LED driving circuit for driving the plurality of red LEDs provided in the plurality of LED modules, a green LED driving circuit for driving the plurality of green LEDs provided in the plurality of LED modules, and a blue LED driving circuit for driving the plurality of blue LEDs provided in the plurality of LED modules,

wherein the plurality of red LEDs in the LED modules are electrically connected with each other, the plurality of green LEDs in the modules are electrically connected with each other, and the plurality of blue LEDs in the LED modules are electrically connected with each other.

2. The backlight unit according to claim 1, wherein each of the LED modules comprises a red LED array including the plurality of red LEDs connected in series, a green LED array including the plurality of green LEDs connected in series, and a blue LED array including the plurality of blue LEDs connected in series.

3. The backlight unit according to claim 2, wherein the red, green and blue LED arrays in one of the LED modules are connected in parallel with the red, green and blue LED arrays in another one of the LED modules, respectively.

4. The backlight unit according to claim 2, wherein each of the red, green and blue LED arrays in one of the LED modules is connected in series with the red, green and blue LED arrays in another one of the LED modules, respectively.

5. The backlight unit according to claim 2, wherein the red, green and blue LED arrays are connected in series, respectively, in at least two of the LED modules to form red, green and blue LED array series-connection structures, and

wherein the red, green and blue LED array series-connection structures are connected in parallel, respectively.

6. The backlight unit according to claim 2, wherein each of the LED modules comprises a red LED array group including the plurality of red LED arrays connected in parallel, a green LED array group including the plurality of green LED arrays connected in parallel, and a blue LED array group including the plurality of blue LED arrays connected in parallel.

7. The backlight unit according to claim 6, wherein the red, green and blue LED array groups in one of the LED modules are connected in parallel with the red, green and blue LED array groups in another one of the LED modules, respectively.

8. The backlight unit according to claim 6, wherein the red, green and blue LED array groups in one of the LED modules are connected in series with the red, green and blue LED array groups in another one of the LED modules, respectively.

9. The backlight unit according to claim 6, wherein the red, green and blue LED array groups are connected in series, respectively, in at least two of the LED modules to form a plurality of red, green and blue LED array group series-connection structures, and

wherein the red, green and blue LED array group series-connection structures are connected in parallel, respectively.