Compact light conversion device and light source with high thermal conductivity wavelength conversion material

• US 20080149166A1
• Filed: 12/21/2006
• Published: 06/26/2008
• Est. Priority Date: 12/21/2006
• Status: Abandoned Application

• Current Assignee: Goldeneye, Inc.
• Original Assignee: Goldeneye, Inc.
• Inventors: Livesay, William R., Beeson, Karl W., Zimmerman, Scott M., Ross, Richard L.
• Application Number:
  US11/644,678
• Publication Number:
  US 20080149166A1
• Time in Patent Office: Days
• US Class Current: 136/248
• CPC Class Codes: H01L 2224/73265 Layer and wire connectors
• CPC Class Codes: H01L 24/32 of an individual layer connector
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/12041 LED
• CPC Class Codes: H01L 2924/12044 OLED
• CPC Class Codes: H01L 31/02322 comprising luminescent members, e.g. fluorescent sheets upon the device
• CPC Class Codes: H01L 31/024 Arrangements for cooling, heating, ventilating or temperature compensation for photovoltaic devices H01L31/052
• CPC Class Codes: H01L 31/052 Cooling means directly associated or integrated with the PV cell, e.g. integrated Peltier elements for active cooling or heat sinks directly associated with the PV cells cooling means in combination with the PV module H02S40/42
• CPC Class Codes: H01L 33/501 characterised by the materials, e.g. binder
• CPC Class Codes: H01L 33/507 the elements being in intimate contact with parts other than the semiconductor body or integrated with parts other than the semiconductor body
• CPC Class Codes: H01L 33/644 in intimate contact or integrated with parts of the device other than the semiconductor body
• CPC Class Codes: Y02E 10/50 Photovoltaic [PV] energy

Abstract

A light conversion device and high-intensity, solid-state light source utilize wavelength conversion elements with a thermal conductivity greater than 1 watt per meter per degree Kelvin (W/m-K). Exemplary materials that have high thermal conductivity include monocrystalline solids, polycrystalline solids, substantially densified ceramic solids, amorphous solids or composite solids. The light conversion device and high-intensity, solid-state light source have at least one heat sink that is in direct thermal contact with the wavelength conversion element. The heat sink quickly dissipates heat generated within the wavelength conversion element in order to prevent the wavelength conversion element from overheating and undergoing thermal quenching of the wavelength conversion and light emission.

Claims

1. A light conversion device, comprising:

a wavelength conversion element having a light input surface and a light output surface; and

a heat sink in thermal contact with said wavelength conversion element, said heat sink removing heat generated by said wavelength conversion element;

wherein said wavelength conversion element converts light of a first wavelength range into light of a second wavelength range, said second wavelength range being different from said first wavelength range, and wherein said wavelength conversion element is a thermally conducting solid having a thermal conductivity greater than 1 watt per meter per degree Kelvin.

2. A light conversion device as in claim 1, wherein said thermally conducting solid is a monocrystalline solid, a polycrystalline solid, a substantially densified ceramic solid, an amorphous solid or a composite solid.

3. A light conversion device as in claim 2, further comprising a reflector interposed between said wavelength conversion element and said heat sink, wherein said reflector reflects said light of a first wavelength range and reflects said light of a second wavelength range.

4. A light conversion device as in claim 3, further comprising an electrical interconnection means in said wavelength conversion element.

5. A light conversion device as in claim 4, wherein said electrical interconnection means is an electrical connector fabricated on or embedded in a portion of said light input surface.

6. A light conversion device as in claim 4, wherein said wavelength conversion element is electrically conducting, wherein said electrical interconnection means has an electrically conducting heat sink and an electrical contact positioned on said light input surface, and wherein the electrical current path extends from said heat sink through said electrically conducting wavelength conversion element to said electrical contact.

7. A light conversion device as in claim 3, further comprising a first dichroic mirror formed on said light output surface, wherein said first dichroic mirror transmits said light of said second wavelength range and reflects said light of said first wavelength range back into said wavelength conversion element.

8. A light conversion device as in claim 3, further comprising a second dichroic mirror formed on said light input surface, wherein said second dichroic mirror transmits said light of said first wavelength range and reflects said light of said second wavelength range back into said wavelength conversion element.

9. A light conversion device as in claim 3, further comprising light extraction elements fabricated on said light output surface.

10. A light conversion device as in claim 1, wherein said wavelength conversion element has a thermal conductivity greater than ten watts per meter per degree Kelvin.

11. A light conversion device as in claim 1, wherein said wavelength conversion element has a thermal conductivity greater than fifty watts per meter per degree Kelvin.

12. A light source, comprising:

a wavelength conversion element having a light input surface and a light output surface;

a light emitting diode adjacent to said light input surface, wherein said light emitting diode emits internally generated light in a first wavelength range, said light in said first wavelength range being directed through said light input surface; and

a heat sink in thermal contact with said light emitting diode and in thermal contact with said wavelength conversion element, said heat sink removing heat generated by said light emitting diode and heat generated by said wavelength conversion element;

wherein said wavelength conversion element converts said light of said first wavelength range into light of a second wavelength range, said second wavelength range being different from said first wavelength range and wherein said wavelength conversion element is a thermally conducting solid having a thermal conductivity greater than 1 watt per meter per degree Kelvin.

13. A light source as in claim 12, wherein said thermally conducting solid is a monocrystalline solid, a polycrystalline solid, a substantially densified ceramic solid, an amorphous solid or a composite solid.

14. A light source as in claim 12, wherein said wavelength conversion element has a thermal conductivity greater than ten watts per meter per degree Kelvin.

15. A light source as in claim 12, wherein said wavelength conversion element has a thermal conductivity greater than fifty watts per meter per degree Kelvin.

16. A light source, comprising:

a wavelength conversion element having a light input surface and a light output surface;

a first heat sink in thermal contact with said wavelength conversion element, said heat sink removing heat generated by said wavelength conversion element;

a light emitting diode adjacent to said light input surface, wherein said light emitting diode emits internally generated light in a first wavelength range, said light in said first wavelength range directed through said light input surface; and

a second heat sink in thermal contact with said light emitting diode, said second heat sink removing heat generated by said at least one light emitting diode;

wherein said wavelength conversion element converts said light of said first wavelength range into light of a second wavelength range, said second wavelength range being different from said first wavelength range and wherein said wavelength conversion element is a thermally conducting solid having a thermal conductivity greater than 1 watt per meter per degree Kelvin.

17. A light source as in claim 16, wherein said thermally conducting solid is a monocrystalline solid, a polycrystalline solid, a substantially densified ceramic solid, an amorphous solid or a composite solid.

18. A light source as in claim 17, wherein said wavelength conversion element has a thermal conductivity greater than ten watts per meter per degree Kelvin.

19. A light source as in claim 17, wherein said wavelength conversion element has a thermal conductivity greater than fifty watts per meter per degree Kelvin.

20. A light source as in claim 17, further comprising a reflector interposed between said wavelength conversion element and said first heat sink, wherein said reflector reflects said light of said first wavelength range and reflects said light of said second wavelength range.

21. A light source as in claim 17, further comprising an electrical interconnection means in said wavelength conversion element.

22. A light source as in claim 21, wherein said electrical interconnection means is an electrical connector fabricated on or embedded in a portion of said light input surface

23. A light source as in claim 21, wherein said wavelength conversion element and said first heat sink are electrically conducting, wherein said electrical interconnection means has an electrical contact positioned on said light input surface and wherein the electrical current path extends from said first heat sink, through said electrically conducting wavelength conversion element through said electrical contact.

24. A light source as in claim 17, wherein said light emitting diode reflects externally incident light with a reflectivity greater than 40 percent, wherein a portion of said light of a second wavelength range emitted by said wavelength conversion element is directed to said light emitting diode as externally incident light and wherein said externally incident light is reflected by said light emitting diode and directed through said wavelength conversion element and through said output surface, thereby increasing the light output of said light source.

25. A light source as in claim 17, wherein said light emitting diode emits greater than 0.25 optical watt per square millimeter of said internally generated light.

26. A light source as in claim 25, wherein said light emitting diode emits greater than 0.50 optical watt per square millimeter of said internally generated light.

27. A light source as in claim 17, wherein the light flux density of said light of a first wavelength range inside said wavelength conversion element is greater than 0.5 optical watt per cubic millimeter.

28. A light source as in claim 17, wherein the light output intensity of said light of a first wavelength range and said light of a second wavelength range is greater than 0.25 optical watt per square millimeter.