LIGHT EMITTING DIODE DEVICE

• US 20110180824A1
• Filed: 01/26/2010
• Published: 07/28/2011
• Est. Priority Date: 01/26/2010
• Status: Active Grant

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Berryman-Bousquet, Valerie, TAN, Wei-Sin, Zhang, Tong, Heffernan, Jonathan
• Granted Patent: US 8,258,524 B2
• Time in Patent Office: Days
• US Class Current: 257/89
• CPC Class Codes: F21K 9/23 Retrofit light sources for lighting devices with a single fitting for each light source, e.g. for substitution of incandescent lamps with bayonet or threaded fittings
• CPC Class Codes: F21K 9/232 specially adapted for generating an essentially omnidirectional light distribution, e.g. with a glass bulb
• CPC Class Codes: F21K 9/61 using light guides
• CPC Class Codes: F21K 9/64 using wavelength conversion means distinct or spaced from the light-generating element, e.g. a remote phosphor layer
• CPC Class Codes: F21K 9/65 specially adapted for changing the characteristics or the distribution of the light, e.g. by adjustment of parts
• CPC Class Codes: F21V 3/00 Globes; Bowls; Cover glasses with refracting properties F21V5/00; with reflecting properties F21V7/00; characterised by cooling arrangements F21V29/506
• CPC Class Codes: F21Y 2105/10 comprising a two-dimensional array of point-like light-generating elements
• CPC Class Codes: F21Y 2113/13 comprising an assembly of point-like light sources
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: G02B 6/0008 the light being emitted at the end of the fibre

Abstract

A light emitting diode device which includes at least one light emitting diode, a heat-sink chassis having a surface upon which the at least one light emitting diode is mounted, and a waveguide having one end coupled to the at least one light emitting diode for receiving light therefrom. The waveguide has another end which includes a light extraction and redistribution region, and the waveguide is configured to guide light received from the at least one light emitting diode away from the heat-sink chassis and towards the light extraction and redistribution region. The light extraction and redistribution region is configured to extract and redistribute the light from the waveguide.

Claims

1. A light emitting diode device, comprising:

at least one light emitting diode;

a heat-sink chassis having a surface upon which the at least one light emitting diode is mounted; and

a waveguide having one end coupled to the at least one light emitting diode for receiving light therefrom, and another end which includes a light extraction and redistribution region,

wherein the waveguide is configured to guide light received from the at least one light emitting diode away from the heat-sink chassis and towards the light extraction and redistribution region, and the light extraction and redistribution region is configured to extract and redistribute the light from the waveguide.

2. The light emitting diode device according to claim 1, wherein the light extraction and redistribution region is configured to redistribute at least some of the light back towards the heat-sink chassis without the light being shielded by the heat-sink chassis.

3. The light emitting diode device according to claim 1, wherein the light extraction and redistribution region comprises a pocket region on a top section of the waveguide with glass beads located within the pocket.

4. The light emitting diode device according to claim 3, wherein the glass beads are embedded in resin within the pocket region.

5. The light emitting diode device according to claim 1, wherein the light extraction and redistribution region comprises holes formed in the waveguide.

6. The light emitting diode device according to claim 1, wherein the light extraction and redistribution region comprises prism-shaped features formed in the waveguide.

7. The light emitting diode device according to claim 1, wherein the light extraction and redistribution region comprises a partially transmitting mirror.

8. The light emitting diode device according to claim 7, wherein the partially transmitting mirror is configured to redistribute the light in different directions by transmitting a portion and reflecting another portion.

9. The light emitting diode device according to claim 1, wherein the waveguide comprises a lower section adjacent the at least one light emitting diode and an upper section adjacent the light extraction and redistribution region, the lower section having a thermal conductivity which is higher than the thermal conductivity of the upper section, and the light emitting diode device further includes a thermally conductive collar configured to dissipate heat, extracted by the lower section from the at least one light emitting diode, to the heat sink chassis.

10. The light emitting diode device according to claim 9, wherein the lower section comprises aluminum nitride.

11. The light emitting diode device according to claim 9, wherein the lower section comprises optically transparent liquid through which the heat from the at least one light emitting diode is extracted by convection.

12. The light emitting diode device according to claim 1, wherein the waveguide comprises a material which blocks or reduces ultra violet (UV) light exposure to the at least one light emitting diode.

13. The light emitting diode device according to claim 12, wherein the material comprises Poly(methyl methacrylate) (PMMA).

14. The light emitting diode device according to claim 1, comprising a plurality of light emitting diodes mounted to the surface of the heat-sink chassis, and a plurality of waveguides each having one end coupled to a respective at least one of the plurality of light emitting diodes for receiving light therefrom, and another end which includes a light extraction and redistribution region, wherein each of the plurality of waveguides is configured to guide light received from the respective at least one light emitting diode away from the heat-sink chassis and towards the light extraction and redistribution region, and the light extraction and redistribution region is configured to extract and redistribute the light from the waveguide.

15. The light emitting diode device according to claim 14, wherein the light extraction and redistribution region of each of the plurality of waveguides combine to form a common light extraction and redistribution region.

16. The light emitting device according to claim 14, wherein the plurality of light emitting diodes have different temperature or color characteristics.

17. The light emitting device according to claim 1, wherein the light extraction and redistribution region(s) comprise phosphors or nanophosphors.