Light source with secondary emitter conversion element

• US 8,608,328 B2
• Filed: 05/06/2011
• Issued: 12/17/2013
• Est. Priority Date: 05/06/2011
• Status: Active Grant

• Current Assignee: Seoul Semiconductor Co., Ltd.
• Original Assignee: Teledyne Technologies Incorporated
• Inventors: Panagotacos, George W., Pelka, David G.
• Primary Examiner(s): Guharay, Karabi
• Assistant Examiner(s): LEE, NATHANIEL J.
• Application Number:
  US13/102,580
• Publication Number:
  US 20120281389A1
• Time in Patent Office: 956 Days
• Field of Search: 362/84, 362 972- 973, 313/501, 313/506
• US Class Current: 362/84
• CPC Class Codes: A61C 19/003 Apparatus for curing resins by radiation
• CPC Class Codes: A61C 19/066 Bleaching devices; Whitening agent applicators for teeth, e.g. trays or strips
• CPC Class Codes: F21W 2131/202 for dentistry
• CPC Class Codes: G02B 6/4204 the coupling comprising intermediate optical elements, e.g. lenses, holograms encapsulated active devices H01S5/02208, H01L33/52
• CPC Class Codes: G02B 6/4269 with heat sinks or radiation fins
• CPC Class Codes: G02B 6/4298 coupling with non-coherent light sources and/or radiation detectors, e.g. lamps, incandescent bulbs, scintillation chambers

Abstract

A light source is disclosed. The light source includes a primary excitation source configured to emit electromagnetic radiation at a first peak wavelength and a band of wavelengths around the first peak wavelength. A secondary emitter conversion element is optically coupled to the primary excitation source and is configured to absorb at least a portion the electromagnetic radiation at the first peak wavelength from the primary excitation source and emit electromagnetic radiation at a second peak wavelength and a band of wavelengths around the second peak wavelength. The second peak wavelength is longer than the first peak wavelength. A non-imaging optical coupler is optically coupled to the secondary emitter conversion element. An optical system includes the light source optically coupled to a transparent rod.

Claims

1. A light source, comprising:

a primary excitation source configured to emit electromagnetic radiation at a first peak wavelength and a band of wavelengths around the first peak wavelength;

a secondary emitter conversion element optically coupled to the primary excitation source, the secondary emitter conversion element configured to absorb at least a portion the electromagnetic radiation at the first peak wavelength from the primary excitation source and emit electromagnetic radiation at a second peak wavelength and a band of wavelengths around the second peak wavelength, wherein the second peak wavelength is longer than the first peak wavelength;

a non-imaging optical coupler optically coupled to the secondary emitter conversion element; and

a gap between the secondary emitter conversion element and the non-imaging optical coupler;

wherein the gap is in the range of about 250 μ

m to about 500 μ

m.

2. The light source of claim 1, wherein the secondary emitter conversion element comprises a phosphor material.

3. The light source of claim 1, comprising:

a reflective optical cavity configured to receive the secondary emitter conversion element.

4. The light source of claim 3, wherein the reflective optical cavity comprises a seat to receive the secondary emitter conversion element.

5. The light source of claim 3, wherein the reflective optical cavity has a cylindrical shape and the secondary emitter conversion element has a circular shape.

6. The light source of claim 3, wherein an inner surface of the reflective optical cavity has a paraboloidal shape.

7. The light source of claim 3, wherein an inner surface of the reflective optical cavity has an elliptical shape.

8. The light source of claim 3, wherein an inner surface of the reflective optical cavity has a specular reflectivity.

9. The light source of claim 3, wherein an inner surface of the reflective optical cavity has a diffuse reflectivity.

10. The light source of claim 1, comprising:

a substrate to receive the primary excitation source, wherein the substrate comprises a reflective surface; and

a heat transfer element thermally coupled to the substrate.

11. The light source of claim 1, wherein the primary excitation source comprises at least one light-emitting diode (LED).

12. The light source of claim 11, wherein the at least one LED is configured to emit electromagnetic radiation at the first peak wavelength, wherein the first peak wavelength falls in the range of about 365 nm to about 465 nm.

13. The light source of claim 11, wherein the secondary emitter conversion element is configured to emit electromagnetic radiation at the second peak wavelength, wherein the second peak wavelength falls in the range of about 415 nm to about 705 nm.

14. The light source of claim 1, comprising a material disposed in the gap.

15. The light source of claim 14, wherein the material is optical grade Silicone.

16. An optical system, comprising:

a light source; and

a transparent rod optically coupled to the light source;

wherein the light source comprises;

a primary excitation source configured to emit electromagnetic radiation at a first peak wavelength and a band of wavelengths around the first peak wavelength;

a secondary emitter conversion element optically coupled to the primary excitation source, the secondary emitter conversion element configured to absorb at least a portion the electromagnetic radiation at the first peak wavelength from the primary excitation source and emit electromagnetic radiation at a second peak wavelength and a band of wavelengths around the second peak wavelength, wherein the second peak wavelength is longer than the first peak wavelength;

a non-imaging optical coupler optically coupled to the secondary emitter conversion element; and

a gap between the secondary emitter conversion element and the non-imaging optical coupler;

wherein the gap is in the range of about 250 μ

m to about 500 μ

m.

17. The optical system of claim 16, wherein the secondary emitter conversion element comprises a phosphor material.

18. The optical system of claim 16, comprising:

a reflective optical cavity configured to receive the secondary emitter conversion element.

19. A photon engine, comprising:

a primary excitation source configured to emit electromagnetic radiation at a first peak wavelength and a band of wavelengths around the first peak wavelength;

a secondary emitter conversion element optically coupled to the primary excitation source, the secondary emitter conversion element comprising a phosphor material, the secondary emitter conversion element configured to absorb at least a portion the electromagnetic radiation at the first peak wavelength from the primary excitation source and emit electromagnetic radiation at a second peak wavelength and a band of wavelengths around the second peak wavelength, wherein the second peak wavelength is longer than the first peak wavelength;

a reflective optical cavity configured to receive the secondary emitter conversion element;

a heat transfer element thermally coupled to the primary excitation source; and

a non-imaging optical coupler optically coupled to the secondary emitter conversion element; and

a gap between the secondary emitter conversion element and the non-imaging optical coupler;

wherein the gap is in the range of about 250 μ

m to about 500 μ

m.

20. The photon engine of claim 19, wherein the reflective optical cavity comprises a seat to receive the secondary emitter conversion element.

21. The photon engine of claim 19, wherein the reflective optical cavity has a cylindrical shape and the secondary emitter conversion element has a circular shape.

22. The photon engine of claim 19, wherein an inner surface of the reflective optical cavity has a paraboloidal shape.

23. The photon engine of claim 19, wherein an inner surface of the reflective optical cavity has an elliptical shape.

24. The photon engine of claim 19, wherein an inner surface of the reflective optical cavity has a specular reflectivity.

25. The photon engine of claim 19, wherein an inner surface of the reflective optical cavity has a diffuse reflectivity.

26. The photon engine of claim 19, wherein the primary excitation source comprises at least one light-emitting diode (LED).

27. The photon engine of claim 26, wherein the at least one LED is configured to emit electromagnetic radiation at the first peak wavelength, wherein the first peak wavelength falls in the range of about 365 nm to about 465 nm.

28. The photon engine of claim 26, wherein the secondary emitter conversion element is configured to emit electromagnetic radiation at the second peak wavelength, wherein the second peak wavelength falls in the range of about 415 nm to about 705 nm.

29. The photon engine of claim 19, comprising a material disposed in the gap.

30. The photon engine of claim 29, wherein the material is optical grade Silicone.

31. The photon engine of claim 19, comprising a substrate to receive the primary excitation source, wherein the substrate comprises a reflective surface.

32. The photon engine of claim 31, wherein the reflective surface reflects the electromagnetic radiation at the second peak wavelength back into an input surface of the secondary emitter conversion element.

33. A light source, comprising:

a primary excitation source configured to emit electromagnetic radiation at a first peak wavelength and a band of wavelengths around the first peak wavelength;

a secondary emitter conversion element optically coupled to the primary excitation source, the secondary emitter conversion element configured to absorb at least a portion the electromagnetic radiation at the first peak wavelength from the primary excitation source and emit electromagnetic radiation at a second peak wavelength and a band of wavelengths around the second peak wavelength, wherein the second peak wavelength is longer than the first peak wavelength;

a non-imaging optical coupler optically coupled to the secondary emitter conversion element;

a gap between the secondary emitter conversion element and the non-imaging optical coupler; and

a material disposed in the gap.

34. The light source of claim 33, wherein the secondary emitter conversion element comprises a phosphor material.

35. The light source of claim 33, comprising:

a reflective optical cavity configured to receive the secondary emitter conversion element.

36. The light source of claim 35, wherein the reflective optical cavity comprises a seat to receive the secondary emitter conversion element.

37. The light source of claim 35, wherein the reflective optical cavity has a cylindrical shape and the secondary emitter conversion element has a circular shape.

38. The light source of claim 35, wherein an inner surface of the reflective optical cavity has a paraboloidal shape.

39. The light source of claim 35, wherein an inner surface of the reflective optical cavity has an elliptical shape.

40. The light source of claim 35, wherein an inner surface of the reflective optical cavity has a specular reflectivity.

41. The light source of claim 35, wherein an inner surface of the reflective optical cavity has a diffuse reflectivity.

42. The light source of claim 33, comprising:

a substrate to receive the primary excitation source, wherein the substrate comprises a reflective surface; and

a heat transfer element thermally coupled to the substrate.

43. The light source of claim 33, wherein the primary excitation source comprises at least one light-emitting diode (LED).

44. The light source of claim 43, wherein the at least one LED is configured to emit electromagnetic radiation at the first peak wavelength, wherein the first peak wavelength falls in the range of about 365 nm to about 465 nm.

45. The light source of claim 43, wherein the secondary emitter conversion element is configured to emit electromagnetic radiation at the second peak wavelength, wherein the second peak wavelength falls in the range of about 415 nm to about 705 nm.

46. The light source of claim 33, wherein the material is optical grade Silicone.

47. An optical system, comprising:

a light source; and

a transparent rod optically coupled to the light source;

wherein the light source comprises;

a primary excitation source configured to emit electromagnetic radiation at a first peak wavelength and a band of wavelengths around the first peak wavelength;

a secondary emitter conversion element optically coupled to the primary excitation source, the secondary emitter conversion element configured to absorb at least a portion the electromagnetic radiation at the first peak wavelength from the primary excitation source and emit electromagnetic radiation at a second peak wavelength and a band of wavelengths around the second peak wavelength, wherein the second peak wavelength is longer than the first peak wavelength;

a non-imaging optical coupler optically coupled to the secondary emitter conversion element;

a gap between the secondary emitter conversion element and the non-imaging optical coupler; and

a material disposed in the gap.

48. The optical system of claim 47, wherein the secondary emitter conversion element comprises a phosphor material.

49. The optical system of claim 47, comprising:

a reflective optical cavity configured to receive the secondary emitter conversion element.

50. A photon engine, comprising:

a primary excitation source configured to emit electromagnetic radiation at a first peak wavelength and a band of wavelengths around the first peak wavelength;

a secondary emitter conversion element optically coupled to the primary excitation source, the secondary emitter conversion element comprising a phosphor material, the secondary emitter conversion element configured to absorb at least a portion the electromagnetic radiation at the first peak wavelength from the primary excitation source and emit electromagnetic radiation at a second peak wavelength and a band of wavelengths around the second peak wavelength, wherein the second peak wavelength is longer than the first peak wavelength;

a reflective optical cavity configured to receive the secondary emitter conversion element;

a heat transfer element thermally coupled to the primary excitation source;

a non-imaging optical coupler optically coupled to the secondary emitter conversion element;

a gap between the secondary emitter conversion element and the non-imaging optical coupler; and

a material disposed in the gap.

51. The photon engine of claim 50, wherein the reflective optical cavity comprises a seat to receive the secondary emitter conversion element.

52. The photon engine of claim 50, wherein the reflective optical cavity has a cylindrical shape and the secondary emitter conversion element has a circular shape.

53. The photon engine of claim 50, wherein an inner surface of the reflective optical cavity has a paraboloidal shape.

54. The photon engine of claim 50, wherein an inner surface of the reflective optical cavity has an elliptical shape.

55. The photon engine of claim 50, wherein an inner surface of the reflective optical cavity has a specular reflectivity.

56. The photon engine of claim 50, wherein an inner surface of the reflective optical cavity has a diffuse reflectivity.

57. The photon engine of claim 50, wherein the primary excitation source comprises at least one light-emitting diode (LED).

58. The photon engine of claim 57, wherein the at least one LED is configured to emit electromagnetic radiation at the first peak wavelength, wherein the first peak wavelength falls in the range of about 365 nm to about 465 nm.

59. The photon engine of claim 57, wherein the secondary emitter conversion element is configured to emit electromagnetic radiation at the second peak wavelength, wherein the second peak wavelength falls in the range of about 415 nm to about 705 nm.

60. The photon engine of claim 59, wherein the material is optical grade Silicone.

61. The photon engine of claim 50, comprising a substrate to receive the primary excitation source, wherein the substrate comprises a reflective surface.

62. The photon engine of claim 61, wherein the reflective surface reflects the electromagnetic radiation at the second peak wavelength back into an input surface of the secondary emitter conversion element.