LED-Based Illumination System

• US 20080030974A1
• Filed: 08/02/2007
• Published: 02/07/2008
• Est. Priority Date: 08/02/2006
• Status: Abandoned Application

• Current Assignee: Nayef M. Abu-Ageel
• Original Assignee: Nayef M. Abu-Ageel
• Inventors: Abu-Ageel, Nayef M.
• Application Number:
  US11/833,222
• Publication Number:
  US 20080030974A1
• Time in Patent Office: Days
• US Class Current: 362/19
• CPC Class Codes: F21V 13/04 the elements being reflectors and refractors for vehicle rear lights F21S43/40
• CPC Class Codes: F21V 5/007 Array of lenses or refractors for a cluster of light sources, e.g. for arrangement of multiple light sources in one plane combination of two or more refractors F21V5/008
• CPC Class Codes: F21V 5/008 Combination of two or more successive refractors along an optical axis
• CPC Class Codes: F21V 5/04 of lens shape
• CPC Class Codes: F21V 7/09 with a combination of different curvatures
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• 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 19/0066 in the form of an LED array
• CPC Class Codes: G02B 6/065 with dynamic image improvement
• CPC Class Codes: G02B 6/4298 coupling with non-coherent light sources and/or radiation detectors, e.g. lamps, incandescent bulbs, scintillation chambers
• CPC Class Codes: H01L 33/46 Reflective coating, e.g. dielectric Bragg reflector
• CPC Class Codes: H01L 33/58 Optical field-shaping elements
• CPC Class Codes: H01L 33/60 Reflective elements

Abstract

An illumination system includes one or more extraction optical elements to efficiently extract light from light emitting diodes (LEDs) by reducing light losses within the LED structure. Micro-element optical plates can also be included in the system to provide control over the spatial distribution of light in terms of intensity and angle.

Claims

1. An illumination system, comprising:

a light emitting diode (LED); and

an extraction optical element, mounted to the LED for receiving light emitted from the LED, having a refractive index that matches the refractive index of the LED.

2. The illumination system of claim 1, wherein the refractive index of the extraction optical element ranges between 1.4 and 3.5.

3. The illumination system of claim 1, wherein the extraction optical element is bonded to the LED with an optically transparent adhesive layer.

4. The illumination system of claim 1, further comprising:

a tapered hollow light pipe receiving light output from the extraction optical element.

5. The illumination system of claim 1, further comprising:

a tapered solid light pipe receiving light output from the extraction optical element.

6. The illumination system of claim 1, further comprising a collimating lens.

7. The illumination system of claim 1, further comprising a tapered light tunnel configured to form a cavity around the extraction optical element.

8. The illumination system of claim 1, further comprising a wavelength converting layer formed between the LED and the extraction optical element.

9. The illumination system of claim 1, further comprising a polarization layer formed between the LED and the extraction optical element.

10. The illumination system of claim 1, wherein the extraction optical element includes an optically transmissive square body and an optical micro-element plate in optical communication with the square body.

11. The illumination system of claim 1, wherein the extraction optical element includes:

a diffusive layer;

a lens; and

an optically transmissive body between the lens and the diffusive layer.

12. The illumination system of claim 1, wherein the extraction optical element includes:

a lens; and

a diffusive layer formed on the lens.

13. An illumination system, comprising:

a light emitting diode (LED); and

an extraction optical element configured to received light emitted from the LED; and

a refractive index matching layer formed between the extraction optical element and the LED.

14. The illumination system of claim 13, wherein the refractive index of the refractive index matching layer ranges between 1.4 and 3.5.

15. The illumination system of claim 13, wherein the extraction optical element includes an optically transmissive square body and an optical micro-element plate in optical communication with the square body.

16. The illumination system of claim 13, wherein the extraction optical element includes:

a diffusive layer;

a lens; and

an optically transmissive body between the lens and the diffusive layer.

17. The illumination system of claim 13, wherein the extraction optical element includes:

a lens; and

a diffusive layer formed on the lens.

18. The illumination system of claim 13, further comprising a tapered light tunnel configured to form a cavity around the extraction optical element.

19. The illumination system of claim 13, further comprising a wavelength converting layer formed between the LED and the extraction optical element.

20. The illumination system of claim 13, further comprising a polarization layer formed between the LED and the extraction optical element.