Solid-state light emitting devices with photoluminescence wavelength conversion

Patent metadata

Field	Value
Publication number	US-8957585-B2
Application number	US-201314141275-A
Country	US
Kind code	B2
Filing date	Dec 26, 2013
Priority date	Oct 5, 2010
Publication date	Feb 17, 2015
Grant date	Feb 17, 2015

Abstract

A solid-state light emitting device comprises a light transmissive thermally conductive circuit board; an array of solid-state light emitters (LEDs) mounted on, and electrically connected to, at least one face of the circuit board; and a photoluminescence wavelength conversion component. The wavelength conversion component comprises a mixture of particles of at least one photoluminescence material (phosphor) and particles of a light reflective material. The emission product of the device comprises the combined light generated by the LEDs and the photoluminescence material. The wavelength conversion component can comprise a layer of the phosphor material and particles of a light reflective material applied directly to the array of LEDs in the form of an encapsulant. Alternatively the photoluminescence component is a separate component and remote to the array of LEDs such as tubular component that surrounds the LEDs.

First claim

What is claimed is:

1. A light emitting device comprising:
a light transmissive circuit board;
a first array of solid-state light emitters mounted on, and electrically connected to, a first face of the light transmissive circuit board, wherein the first array of solid-state light emitters are operable to generate excitation light; and
a photoluminescence wavelength conversion component comprising a mixture of particles of at least one photoluminescence material and particles of a light reflective material, wherein the photoluminescence wavelength conversion component is configured such that in operation a portion of the excitation light generated by the first array solid-state light emitter is emitted through the photoluminescence wavelength conversion component to contribute to a final visible emission product.

2. The light emitting device of claim 1 , further comprising a second array of solid-state light emitters mounted on, and electrically connected to, a second face of the light transmissive circuit board.

3. The light emitting device of claim 1 , wherein the light transmissive circuit board has a transmittance of at least 50% to visible light.

4. The light emitting device of claim 1 , wherein the light transmissive circuit board is thermally conductive.

5. The light emitting device of claim 4 , wherein at least a part of the light transmissive circuit board is selected from the group consisting of: magnesium oxide, sapphire, aluminum oxide, quartz glass, aluminum nitride and diamond.

6. The light emitting device of claim 1 , wherein the photoluminescence component comprises a mixture of the at least one photoluminescence material and particles of the light reflective material applied directly to the, or each, array of solid-state light emitters.

7. The light emitting device of claim 1 , wherein the photoluminescence component is remote to the, or each, array of solid-state light emitters.

8. The light emitting device of claim 7 , wherein a surface of the wavelength conversion component is locatable at a distance of at least 5 mm from the plurality of solid-state light emitters.

9. The light emitting device of claim 7 , wherein the wavelength conversion component comprises a substantially cylindrical tube.

10. The light emitting device of claim 1 , wherein the light reflective material has a particle size in a range selected from the group consisting of: 0.01 μm to 10 μm; 0.01 μm to 1 μm and 0.1 μm to 1 μm.

11. The light emitting device of claim 1 , wherein a weight percent loading of light reflective material to the at least one photoluminescence material is in a range selected from the group consisting of: 0.01% to 10%; 0.01% to 1%; 0.1% to 1% and 0.5% to 1%.

12. The light emitting device of claim 1 , wherein the light reflective material is selected from the group consisting of: magnesium oxide, titanium dioxide, barium sulfate and combinations thereof.

13. The light emitting device of claim 1 , wherein the wavelength conversion component is selected from the group consisting of: a light transmissive substrate on which the mixture of photoluminescence material and light reflective material is provided as at least one layer and a light transmissive substrate having the mixture of photoluminescence material and light reflective material homogeneously distributed throughout its volume.

14. The light emitting device of claim 1 , wherein the particles of the light reflective material corresponds to a particle size such that the particles scatter excitation light generated by the solid-state light emitters relatively more than light generated by the at least one phosphor material.

15. The light emitting device of claim 1 , further comprising a light diffusing layer that is adjacent to the photoluminescence wavelength conversion component.

16. The light emitting device of claim 15 , in which the light diffusing layer comprises particles of light reflective material corresponding to a particle size such that the particles scatter excitation light generated by the solid-state light emitters relatively more than light generated by the at least one photoluminescence material.

17. The light emitting device of claim 16 , wherein the light reflective material has a particle size in a range 100 nm to 150 nm.

Assignees

• Intematix Corp
• Intermatix Corp

Inventors

• Li Yi-Qun
• Melman Jonathan
• Yuan Xianglong
• Dai Bing
• Wang Gang
• Edwards Charles

Classifications

• F21Y2105/10

  comprising a two-dimensional [2D] array of point-like light-generating elements · CPC title

• F21Y2115/10

  Light-emitting diodes [LED] · CPC title

• F21V23/005

  the substrate is supporting also the light source · CPC title

• F21V7/26

  the material comprising photoluminescent substances · CPC title

• H10W74/00

  Encapsulations, e.g. protective coatings · CPC title