Surface light emitting apparatus

• US 7,402,940 B2
• Filed: 01/18/2006
• Issued: 07/22/2008
• Est. Priority Date: 01/19/2005
• Status: Active Grant

• Current Assignee: Nichia Corporation
• Original Assignee: Nichia Corporation
• Inventors: Nakano, Koji, Inuzuka, Tomoaki
• Primary Examiner(s): Patel; Vip
• Application Number:
  US11/333,249
• Publication Number:
  US 20060158080A1
• Time in Patent Office: 916 Days
• Field of Search: 313/498, 313/512
• US Class Current: 313/113
• CPC Class Codes: G02F 1/133603 with LEDs
• CPC Class Codes: G02F 1/133605 including specially adapted reflectors
• CPC Class Codes: G02F 1/133611 including means for improving the brightness uniformity

Abstract

A surface light emitting apparatus that can be made smaller in depth and lighter in weight and has high uniformity in luminance over the light emitting surface is disclosed. The surface light emitting apparatus of the present invention comprising a substrate, a plurality of light sources on the substrate, and a plurality of reflectors on the substrate, each of the reflectors having a first surface that covers the light sources and a second surface that reflects or scatters the irradiated light, wherein the reflectors are disposed so that the second surface is irradiated with a light emitted by the light source by the first surface of the adjacent reflector, and the light reflected or scattered by the second surface is emitted to outside.

Claims

1. A surface light emitting apparatus comprising;

a substrate,

a plurality of light sources on said substrate, and

a plurality of reflectors on said substrate, each of said reflectors having a first surface that covers the light sources and a second surface that reflects or scatters the irradiated light,

wherein said reflectors are disposed so that said first surface of each of said reflectors reflects the light emitted by one or more of said light sources to irradiate the second surface of the adjacent reflector, and the light reflected or scattered by said second surface is emitted outwardly.

2. The surface light emitting apparatus according to claim 1;

wherein said first surface is reflecting surface of a curved surface.

3. The surface light emitting apparatus according to claim 2;

wherein said second surface is a rough surface.

4. The surface light emitting apparatus according to claim 1;

wherein each of said first surface covers said light sources disposed on a straight line and said reflectors are arranged in parallel in a longitudinal direction.

5. The surface light emitting apparatus according to claim 4;

wherein said curved surface comprises a part of a parabolic cylinder surface having a focal axis parallel to said straight line.

6. The surface light emitting apparatus according to claim 5;

wherein said second surface is a rough surface.

7. The surface light emitting apparatus according to claim 4;

wherein said curved surface comprises a part of a hyperbolic cylinder surface having a focal axis parallel to said straight line.

8. The surface light emitting apparatus according to claim 4;

wherein said curved surface comprises a part of an elliptic cylinder surface having a focal axis parallel to said straight line.

9. The surface light emitting apparatus according to claim 4;

wherein said second surface is a rough surface.

10. The surface light emitting apparatus according to claim 1;

wherein said second surface is a rough surface.

11. The surface light emitting apparatus according to claim 10;

wherein said second surface scatters the irradiated light by reflecting.

12. The surface light emitting apparatus according to claim 1;

wherein said light source is a light emitting diode.

13. The surface light emitting apparatus according to claim 12;

wherein a luminescent color of said light emitting diode is white.

14. The surface light emitting apparatus according to claim 13;

wherein said light emitting diode has a light emitting diode chip and a fluorescent material which converts a wavelength of the light from the light emitting diode chip.

15. The surface light emitting apparatus according to claim 13;

wherein said light emitting diode has a plurality of light emitting diode chip of which luminescent colors are different from each other.

16. The surface light emitting apparatus according to claim 1;

further comprising, one or more prism sheets above said second surface.