Light emitting diode package

• US 20050285133A1
• Filed: 06/14/2005
• Published: 12/29/2005
• Est. Priority Date: 06/18/2004
• Status: Active Grant

• Current Assignee: InnoLux Corporation
• Original Assignee: CHI MEI Optoelectronics Corporation
• Inventors: Hung, Chen-Pin
• Granted Patent: US 7,365,370 B2
• Time in Patent Office: Days
• US Class Current: 257/99
• CPC Class Codes: G02B 19/0028 refractive and reflective surfaces, e.g. non-imaging catadioptric systems
• CPC Class Codes: G02B 19/0061 the light source comprising a LED semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission H01L33/00
• CPC Class Codes: G02B 27/0944 Diffractive optical elements, e.g. gratings, holograms gratings per se G02B5/18; holograms used as optical elements per se G02B5/32
• CPC Class Codes: G02B 27/0983 being curved
• CPC Class Codes: H01L 33/54 having a particular shape
• CPC Class Codes: H01L 33/58 Optical field-shaping elements
• CPC Class Codes: H01L 33/60 Reflective elements
• CPC Class Codes: H10K 50/85 Arrangements for extracting light from the devices
• CPC Class Codes: H10K 59/879 comprising refractive means, e.g. lenses

Abstract

A light emitting diode package includes a light emitting diode device and a lens encapsulating the light emitting diode device. The lens includes two reflective surfaces disposed at either side of a central axis, and a plurality of diffractive surfaces disposed between the reflective surfaces and each of the diffractive surfaces has a tilt angle respective to the central axis. Portions of light beams incident to each of the reflective surfaces are reflected to at least one diffractive surface and are diffracted and collected into a convergent angle.

Claims

1. A light emitting diode package comprising:

a light emitting diode device; and

a lens encapsulating said light emitting diode device, wherein said lens further comprises,

two reflective surfaces disposed at either side of a central axis, and

a plurality of diffractive surfaces disposed between said reflective surfaces, each of said diffractive surfaces having a tilt angle respective to said central axis, wherein portions of light beams incident to each of said reflective surfaces are reflected to at least one diffractive surface and then diffracted and collected into a convergent angle.

2. The light emitting diode package of claim 1, wherein said reflective surfaces are disposed symmetrically on both sides of said central axis.

3. The light emitting diode package of claim 1, wherein portions of light beams incident to each of said reflective surfaces are reflected to at least one diffractive surface after each reflective surface generates a total internal reflection.

4. The light emitting diode package of claim 1, wherein at least two diffractive surfaces are disposed symmetrically on both sides of said central axis.

5. The light emitting diode package of claim 1, wherein two of said diffractive surfaces form an acute angle respective to each reflective surface and the remaining diffractive surfaces form a hemispherical surface.

6. The light emitting diode package of claim 1, wherein two of said diffractive surfaces form an acute angle respective to each reflective surface and the remaining diffractive surfaces form a triangular surface.

7. The light emitting diode package of claim 1, wherein the light from said light emitting diode device directly projected to at least a diffractive surface is diffracted by said diffractive surface and collected to said convergent angle.

8. A backlight module comprising:

a light guide plate;

at least one optical film disposed above said light guide plate; and

at least one illuminating device disposed in proximity to the side of said light guide plate, wherein said illuminating device further comprises,

an illuminating semiconductor device, and

a lens disposed above said illuminating semiconductor device, wherein said lens further comprises,

at least one reflective surface, and

at least one diffractive surface disposed in proximity to said reflective surface and said diffractive surface having a tilt angle respective to said central axis of said lens, wherein a first portion of light beams is reflected by said reflective surface to said diffractive surface, diffracted by said diffractive surface, and collected into a convergent angle after the light produced by said illuminating semiconductor device enters said lens.

9. The backlight module of claim 8, wherein a second portion of light beams is projected directly to said diffractive surface, diffracted by said diffractive surface, and collected into a convergent angle after the light produced by said illuminating semiconductor device enters said lens.

10. The backlight module of claim 8, wherein said illuminating semiconductor device is a light emitting diode chip.

11. The backlight module of claim 8, wherein said reflective surfaces are disposed symmetrically on both sides of said central axis.

12. The backlight module of claim 8, wherein said diffractive surfaces are disposed symmetrically on both sides of said central axis.

13. The backlight module of claim 8, wherein said convergent angle forms a ±

25°

angle with respective to said central axis.

14. A flat panel display comprising:

a display panel;

a light guide plate disposed below said display panel;

at least one optical film disposed between said display panel and said light guide plate; and

at least one illuminating device disposed in proximity to the side of said light guide plate, wherein said illuminating device further comprises,

an illuminating semiconductor device, and

a lens disposed above said illuminating semiconductor device, wherein said lens further comprises,

at least one reflective surface; and

at least one diffractive surface disposed in proximity to said reflective surface and said diffractive surface having a tilt angle respective to said central axis of said lens, wherein a first portion of light beams is reflected by said reflective surface to said diffractive surface, diffracted by said diffractive surface, and collected into a convergent angle after the light produced by said illuminating semiconductor device enters said lens.

15. The flat panel display of claim 14, wherein a second portion of light beams is projected directly to said diffractive surface, diffracted by said diffractive surface, and collected into a convergent angle after the light produced by said illuminating semiconductor device enters said lens.

16. The flat panel display of claim 14, wherein said illuminating semiconductor device is a light emitting diode chip.

17. The flat panel display of claim 14, wherein said lens comprises a polycarbonate (PC) lens, a polymethylmethacrylate (PMMA) lens, a resin lens, or a glass lens.

18. The flat panel display of claim 14, wherein said convergent angle forms a ±

25°

angle with said central axis.

19. The flat panel display of claim 14, wherein said optical film is a diffuser plate.

20. The flat panel display of claim 14, wherein said optical film is a prism.