Solid state light source emitting warm light with high CRI

• US 8,684,559 B2
• Filed: 06/04/2010
• Issued: 04/01/2014
• Est. Priority Date: 06/04/2010
• Status: Active Grant

• Current Assignee: IDEAL Industries Lighting, LLC (Ideal Industries Incorporated)
• Original Assignee: CREE Incorporated (Wolfspeed, Inc.)
• Inventors: Van De Ven, Antony, Negley, Gerald, Pickard, Paul Kenneth
• Primary Examiner(s): Truong, Bao Q
• Application Number:
  US12/794,491
• Publication Number:
  US 20110299284A1
• Time in Patent Office: 1,397 Days
• Field of Search: 362/293, 362/2, 362/583, 362/510, 362/800, 362/311.02, 313/112, 313/580, 257/98
• US Class Current: 362/293
• CPC Class Codes: F21K 9/233 specially adapted for generating a spot light distribution, e.g. for substitution of reflector lamps
• CPC Class Codes: F21K 9/60 Optical arrangements integrated in the light source, e.g. for improving the colour rendering index or the light extraction
• CPC Class Codes: F21V 11/06 using crossed laminae or strips , e.g. grid-shaped louvers; using lattices or honeycombs
• CPC Class Codes: F21V 13/04 the elements being reflectors and refractors for vehicle rear lights F21S43/40
• CPC Class Codes: F21V 13/08 the elements being filters or photoluminescent elements and reflectors
• CPC Class Codes: F21V 13/14 the elements being filters or photoluminescent elements, reflectors and refractors
• CPC Class Codes: F21V 31/04 Provision of filling media
• CPC Class Codes: F21V 7/0025 Combination of two or more reflectors for a single light source array of reflectors for a cluster of light sources F21V7/0083
• CPC Class Codes: F21V 9/08 for producing coloured light, e.g. monochromatic; for reducing intensity of light with provision for controlling the colour F21V9/40
• CPC Class Codes: F21V 9/20 Dichroic filters, i.e. devices operating on the principle of wave interference to pass specific ranges of wavelengths while cancelling others
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: G02B 5/20 Filters polarising elements G02B5/30
• CPC Class Codes: H05B 45/20 Controlling the colour of the light

Abstract

Solid state light sources, lighting devices and lamps arranged to provide emission with a warm temperature and high CRI. One embodiment of a solid state lighting device according to the present invention comprises a light emitting diode (LED) device capable of emitting light in an emission spectrum. A filter arranged so that at least some light from the LED light source passes through it, with the filter filtering at least some of one or more portions of the light source emission spectrum. The resulting light source light has a different temperature but substantially the same CRI after passing through the filter.

Claims

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

an LED light source capable of emitting light in an emission spectrum; and

a filter arranged so that at least some light from said LED light source passes through said filter, said filter filtering at least some of said light source emission spectrum, said light source light having a different color temperature but substantially the same CRI after passing through said filter.

2. The LED device of claim 1, wherein said filtering comprises filtering at least some of one or more portions of said emission spectrum.

3. The LED device of claim 1, comprising an LED lamp having a lamp housing with an emission opening, said light source emitting out said emission opening.

4. The LED device of claim 3, wherein said filter is at least partially over said emission opening.

5. The LED device of claim 3, wherein in said filter is mounted to the inside of said housing.

6. The LED device of claim 3, further comprising a housing lens, said filter comprising a colorant in said lens.

7. The LED device of claim 1, wherein said filter comprises a dome at least partially covering said light source.

8. The LED device of claim 1, wherein said light source further comprises an encapsulant, said filter comprising a colorant in said encapsulant.

9. The LED device of claim 1, wherein said light source light has a different color temperature of 1700K or higher after passing through said filter.

10. The LED device of claim 9, wherein said CRI of said filtered light is 90% or more of the CRI of said light source light before filtering.

11. The LED device of claim 9, wherein said CRI of said filtered light is 80 or more.

12. The LED device of claim 1, wherein said light source light has a color temperature of 2000K or higher after passing through said filter.

13. The LED device of claim 12, wherein said CRI of said filtered light is 90% or more of the CRI of said light source light before filtering.

14. The LED device of claim 12, wherein said CRI of said filtered light is 80 or more.

15. The LED device of claim 1, wherein a color point of the light emitted from the light source is within 7 MacAdam ellipses of the black body locus and where a color point of the filtered light source light is also within 7 MacAdam ellipses of the black body locus.

16. The LED device of claim 1, wherein a color point of the light emitted from the light source is within 3 MacAdam ellipses of the black body locus and where a color point of the filtered light source light is also within 3 MacAdam ellipses of the black body locus.

17. The LED device of claim 1, wherein the light emitted from the light source has a color temperature of 2700K or higher and wherein the filtered light source light has a color temperature of 2500K or lower.

18. A light emitting diode (LED) lamp, comprising:

an LED light source emitting light in a white light emission spectrum; and

a filter arranged so that at least some light from said LED light source passes through said filter, said filter filtering at least some of a blue portion of said emission spectrum and at least some of a green/yellow portion of said spectrum, said filtered light source light having a lower color temperature but substantially the same CRI after passing through said filter.

19. The LED lamp of claim 18, wherein said filter filters approximately 40% of said blue portion and approximately 20% of said green/yellow portion.

20. The LED lamp of claim 19, wherein said filtered light has a color temperature that is approximately 2400K or greater.

21. The LED lamp of claim 19, wherein said filtered light has a CRI that is 90 or greater.

22. The LED lamp of claim 18, wherein said filter filters approximately 90% of said blue portion and approximately 45% of said green/yellow portion.

23. The LED lamp of claim 22, wherein said filtered light has a color temperature that is approximately 1800K or greater.

24. The LED lamp of claim 22, wherein said filtered light has a CRI that is 89 or greater.

25. The LED lamp of claim 18, wherein both a color point of the light emitted from the LED light source and a color point of the filtered light source light are within 7 MacAdam ellipses of the black body locus.

26. The LED lamp of claim 18, wherein both a color point of the light emitted from the LED light source and a color point of the filtered light source light are within 3 MacAdam ellipses of the black body locus.

27. The LED lamp of claim 25, wherein the light emitted from the light source has a color temperature of 2700K or higher and wherein the filtered light source light has a color temperature of 2500K or lower.

28. A light emitting diode (LED) device, comprising:

an LED light source emitting light with a color temperature and CRI; and

a means for filtering light from said LED light source to produce light with a different color temperature and substantially the same CRI as said light from said LED light source.

29. The LED device of claim 28, wherein said filtering means comprises an absorbing filter.

30. The LED device of claim 28, wherein said filtering means comprises a reflecting filter.

31. The LED device of claim 28, wherein said filtering means comprises a dichroic filter.

32. The LED device of claim 28, wherein LED light source emits light in an emission spectrum, wherein said filtering means filters at least some of one or more portions of said emission spectrum.

33. A method for producing warm color temperature light with a high CRI, comprising:

providing a white light having a white light color temperature and a high CRI; and

filtering a least some of one or more spectral portions from said white light emission spectrum, said filtered light having an emission spectrum with a temperature lower than said white light color temperature and a CRI that is substantially the same as said high CRI.

34. The method of claim 33, wherein filtering further comprises filtering at least some of one or more spectral portions from said white light emission spectrum, said filtered light also comprising a white light emission spectrum.

35. A light emitting diode (LED) device, comprising:

an LED light source capable of emitting light in an emission spectrum and having a first color point that is within 7 MacAdam ellipses of a first nominal value on the black body locus; and

a filter arranged so that at least some light from said LED light source passes through said filter, said filter filtering at least some of one or more portions of said light source emission spectrum, the filtered light source light having a second color point that is within 7 MacAdam ellipses of a second nominal value on the black body locus.

36. The LED device of claim 35, wherein said first color point is within 3 MacAdam ellipses of said first nominal value on the black body locus and said second color point is within 3 MacAdam ellipses of said second nominal value on the black body locus.

37. The LED device of claim 35, wherein less than 50% of the lumens output by the LED light source are filtered by the filter.

38. The LED device of claim 35, wherein less than 25% of the lumens output by the LED light source are filtered by the filter.

39. The LED device of claim 35, wherein light emitted by the LED light source has a color temperature of 2700K or greater and the filtered light source light has a color temperature of 2500K or lower.