Plane light source and LCD backlight unit having the same

• US 8,488,081 B2
• Filed: 07/20/2010
• Issued: 07/16/2013
• Est. Priority Date: 08/30/2007
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Han, Seong Yeon, Hahm, Hun Joo, Kim, Hyung Suk, Jeong, Young June, Park, Young Sam, Yoo, Chul Hee
• Primary Examiner(s): KIANNI, KAVEH C
• Application Number:
  US12/839,945
• Publication Number:
  US 20100284186A1
• Time in Patent Office: 1,092 Days
• Field of Search: 349/69, 349/64
• US Class Current: 349/69
• CPC Class Codes: G02F 1/133603 with LEDs

Abstract

There are provided a plane light source and an LCD backlight unit having the same. A plane light source including light emitting device matrixes each having a plurality of light emitting devices arranged in rows and columns on a substrate according to an aspect of the invention includes: a first matrix having a plurality of light emitting devices arranged in rows and columns; and a second matrix having a plurality of light emitting devices arranged in rows and columns, the light emitting devices each located within a rectangle formed by four adjacent light emitting devices included in the first matrix, and forming angles θ satisfying the condition of 45°≦θ≦55° therebetween on the basis of a horizontal direction, wherein among pitches between one light emitting devices included in the light emitting device matrixes and another lighting light emitting device adjacent to the light emitting device, a pitch P1 between the light emitting device and the light emitting device diagonally across from the light emitting device satisfies the condition of 25 mm≦P1≦29 mm, and a pitch P2 between the light emitting device and another light emitting device located in a horizontal direction satisfies the condition of 34 mm≦P2≦38 mm.

Claims

1. A plane light source including light emitting device matrixes each having a plurality of light emitting devices arranged in rows and columns on a substrate, the plane light source comprising:

a first matrix having a plurality of light emitting devices arranged in rows and columns;

a second matrix having a plurality of light emitting devices arranged in rows and columns, the light emitting devices each located within a rectangle formed by four adjacent light emitting devices included in the first matrix, and forming angles θ

satisfying the condition of 45°

≦

θ

≦

55°

therebetween on the basis of a horizontal direction;

a side wall located at the edges of an upper surface of the substrate encompassing the plurality of light emitting devices, the side wall having an inclined surface; and

a reflective layer formed on the substrate, the reflective layer reflecting from the plurality of light emitting devices,

wherein among pitches between one light emitting devices included in the light emitting device matrixes and another lighting light emitting device adjacent to the light emitting device, a pitch P1 between the light emitting device and the light emitting device diagonally across from the light emitting device satisfies the condition of 25 mm≦

P1≦

29 mm, and a pitch P2 between the light emitting device and another light emitting device located in a horizontal direction satisfies the condition of 34 mm≦

P2≦

38 mm.

2. The plane light source of claim 1, wherein each of the light emitting devices included in the second matrix is located at the center of the rectangle.

3. The plane light source of claim 1, wherein the light emitting device emits white light.

4. The plane light source of claim 1, further comprising a diffusion sheet disposed along a light emission path of the light emitting devices.

5. The plane light source of claim 1, wherein the light emitting device is a light emitting diode (LED).