Highly Efficient Light-Emitting Diode

• US 20090050905A1
• Filed: 08/19/2008
• Published: 02/26/2009
• Est. Priority Date: 08/20/2007
• Status: Abandoned Application

• Current Assignee: Nayef M. Abu-Ageel
• Original Assignee: Nayef M. Abu-Ageel
• Inventors: Abu-Ageel, Nayef M.
• Application Number:
  US12/194,535
• Publication Number:
  US 20090050905A1
• Time in Patent Office: Days
• US Class Current: 257/80
• CPC Class Codes: H01L 33/10 with a light reflecting structure, e.g. semiconductor Bragg reflector
• CPC Class Codes: H01L 33/20 with a particular shape, e.g. curved or truncated substrate
• CPC Class Codes: H01L 33/46 Reflective coating, e.g. dielectric Bragg reflector
• CPC Class Codes: H01L 33/58 Optical field-shaping elements

Abstract

A high extraction efficiency light-emitting diode (LED) capable of producing a light beam of selected cross-section and selected spatial distribution of light in terms of intensity and angle is disclosed. The LED utilizes micro and/or nano optical elements in order to extract more light at one or more specified cone angles.

Claims

1. A light-emitting diode (LED), comprising:

an active layer for emitting light; and

an array of optical micro-elements configured to receive light emitted from the active layer.

2. The LED of claim 1, wherein the array of optical elements includes:

at least one convex-shaped light guide.

3. The LED of claim 2, wherein the active layer passes within the convex-shaped light guide.

4. The LED of claim 2, wherein the active layer is located below a lower side of the convex-shaped light guide.

5. The LED of claim 2, wherein the convex-shaped light guide includes a curved sidewall.

6. The LED of claim 2, wherein the convex-shaped light guide includes two sidewall segments, each formed at a different angle relative to a predetermined axis.

7. The LED of claim 2, wherein the convex-shaped light guide includes three sidewall segments, each formed at a different angle relative to a predetermined axis.

8. The LED of claim 2, further comprising a lens having a diameter equivalent to the diameter of the convex-shaped light guide and configured to receive light exiting the convex-shaped light guide.

9. The LED of claim 2, further comprising:

photonic crystals formed at an input aperture of the convex-shaped light guide.

10. The LED of claim 1, further comprising:

an epitaxial layer; and

a plurality of photonic crystals formed in the epitaxial layer.

11. The LED of claim 1, further comprising electrical contacts formed at the entrance aperture of at least one of the optical micro-elements.

12. The LED of claim 1, wherein the array of optical micro-elements includes:

a first layer of photonic crystals configured to receive light from the active layer; and

a second layer of photonic crystals configured to receive light from the first layer of photonic crystals.

13. The LED of claim 12, wherein the array of optical elements further includes:

an array of lens configured to receive light exiting from the second layer of photonic crystals.

14. The LED of claim 12, wherein the array of optical elements further includes:

a third layer of photonic crystals configured to receive light from the second layer of photonic crystals.

15. A light-emitting diode (LED), comprising:

an active layer for emitting light;

an array convex-shaped light guides configured to receive light emitted from the active layer; and

a layer of photonic crystals configured to receive light exiting the array of convex-shaped light guides.

16. The LED of claim 15, further comprising:

an array of lens having a one-to-one correspondence with the convex-shaped light guides, configured to receive light emitted from the layer of photonic crystals.

17. The LED of claim 15, further comprising:

photonic crystals formed at the entrance aperture of each of the convex-shaped light guides.

18. The LED of claim 15, further comprising:

an electrode formed between the convex-shaped light guides.

19. The LED of claim 18, wherein the electrode is formed on an exterior surface of the LED.

20. The LED of claim 15, further comprising:

a first group of photonic crystals formed at an entrance aperture of each convex-shaped light guide; and

a second group of photonic crystals formed at the entrance aperture of each convex-shaped light guide, the second group of photonic crystals configured to receive light from the first group of photonic crystals.