HIGH CRI LIGHTING DEVICE WITH ADDED LONG-WAVELENGTH BLUE COLOR

• US 20110221330A1
• Filed: 03/09/2010
• Published: 09/15/2011
• Est. Priority Date: 03/09/2010
• Status: Active Grant

• Current Assignee: Creeled Incorporated
• Original Assignee: CREE Incorporated (Wolfspeed, Inc.)
• Inventors: LeToquin, Ronan P., Keller, Bernd P., Van De Ven, Antony Paul, Negley, Gerald H., Andrews, Peter Scott
• Granted Patent: US 8,508,127 B2
• Time in Patent Office: Days
• US Class Current: 313/501
• 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: F21Y 2113/13 comprising an assembly of point-like light sources
• CPC Class Codes: F21Y 2113/17 forming a single encapsulated light source
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: H01L 25/0753 the devices being arranged next to each other
• 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 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 33/504 Elements with two or more wavelength conversion materials

Abstract

Solid state lighting devcies include least one solid state emitter and multiple lumiphors, arranged to output aggregated emissions comprising at least one short wavelength blue peak, at least one long wavelength blue (LWB) peak, at least one yellow and/or green peak, and at least one red and/or orange peak. Presence of long wavelength blue enhances color rendering. At least one solid state emitter may include a short wavelength blue LED, LWB LED, and/or UV LED. Multiple emitters may be provided. Resulting devices may provide CRI greater than 85, efficiency of greater than 50 lm/watt, and color stability in a range of Δu′v′≦0.008 over a temperature change of 75° C.

Claims

1. A lighting device comprising:

a solid state emitter having a dominant wavelength in a range of from 430 nm to 470 nm;

a first lumiphor having a dominant wavelength in a range of from 471 nm to 510 nm;

a second lumiphor having a dominant wavelength in a range of from 511 nm to 585 nm; and

a third lumiphor having a dominant wavelength in a range of from 600 nm to 650 nm;

wherein spectral output of the lighting device includes in combination at least a portion of emissions from each of the solid state emitter, the first lumiphor, the second lumiphor, and the third lumiphor.

2. The lighting device of claim 1, being devoid of any solid state emitter having a dominant wavelength outside a range of from 430 nm to 470 nm and arranged to contribute to or stimulate spectral output of the lighting device.

3. The lighting device of claim 1, wherein the first solid state emitter has a nitride-based active region, and the lighting device is devoid of any solid state emitter having a phosphide-based, arsenide-based, or silicide-based active region and arranged to contribute to or stimulate spectral output of the lighting device.

4. The lighting device of claim 1, adapted to provide a color rendering index of greater than 85, and efficiency of greater than 50 lumens per watt.

5. The lighting device of claim 4, exhibiting color stability with respect to temperature in a range of Δ

u′

v′

≦

0.008 over a temperature change of 75°

C.

6. The lighting device of claim 1, characterized by at least one of the following:

the solid state emitter comprises a LED; and

any of the first lumiphor, the second lumiphor, and the third lumiphor comprises a phosphor.

7. A method comprising illuminating an object, a space, or an environment utilizing a lighting device according to claim 1.

8. A lighting device comprising:

at least one solid state emitter emitting wavelengths substantially in at least one of the ultraviolet (UV) range and the near ultraviolet (NUV) range;

a first lumiphor having a dominant wavelength in a range of from 430 nm to 470 nm;

a second lumiphor having a dominant wavelength in a range of from 471 nm to 510 nm;

a third lumiphor having a dominant wavelength in a range of from 511 nm to 585 nm; and

a fourth lumiphor having a dominant wavelength in a range of from 600 nm to 650 nm;

wherein each lumiphor is arranged to receive emissions from the at least one solid state emitter, and spectral output of the lighting device includes in combination at least a portion of emissions from each of the first lumiphor, the second lumiphor, the third lumiphor, and the fourth lumiphor.

9. The lighting device of claim 8, being devoid of any additional solid state emitter having emitting wavelengths substantially outside the ultraviolet range and the near ultraviolet range and arranged to contribute to or stimulate spectral output of the lighting device.

10. The lighting device of claim 8, wherein the at least one solid state emitter has a nitride-based active region, and the lighting device is devoid of any solid state emitter having a phosphide-based or arsenide-based active region and arranged to contribute to or stimulate spectral output of the lighting device.

11. The lighting device of claim 8, adapted to provide a color rendering index of greater than 85, and efficiency of greater than 50 lumens per watt.

12. The lighting device of claim 11, exhibiting color stability with respect to temperature in a range of Δ

u′

v′

≦

0.008 over a temperature change of 75°

C.

13. The lighting device of claim 8, characterized by at least one of the following:

the solid state emitter comprises a LED; and

any of the first lumiphor, the second lumiphor, the third lumiphor, and the fourth lumiphor comprises a phosphor.

14. A method comprising illuminating an object, a space, or an environment utilizing a lighting device according to claim 8.

15. A lighting device comprising:

a first solid state emitter having a dominant wavelength in a range of from 430 nm to 470 nm;

a second solid state emitter having a dominant wavelength in a range of from 471 to 484 nm;

a first lumiphor having a dominant wavelength in a range of from 511 nm to 585 nm, and arranged to interact with at least one of the first solid state emitter and the second solid state emitter to responsively output light; and

a second lumiphor having a dominant wavelength in a range of from 600 to 650 nm, and arranged to interact with at least one of the first solid state emitter and the second solid state emitter to responsively output light;

wherein spectral output of the lighting device includes in combination at least a portion of emissions from each of the first solid state emitter, the second solid state emitter, the first lumiphor, and the second lumiphor.

16. The lighting device of claim 15, wherein each of the first solid state emitter and the second solid state emitter has a nitride-based active region, and the lighting device is devoid of any additional solid state emitter having a phosphide-based or arsenide-based active region and arranged to contribute to or stimulate spectral output of the lighting device.

17. The lighting device of claim 15, embodying least one of the following features:

the first solid state emitter and the second solid state emitter are disposed on or over a common submount;

the first solid state emitter and the second solid state emitter are connected to a common leadframe; and

the first solid state emitter and the second solid state emitter are arranged to emit light for reflection by a common reflector.

18. The lighting device of claim 15, wherein any of the first lumiphor and the second lumiphor is disposed relative to the first emitter and the second emitter in a quantity or concentration that differs with respect to the first emitter and the second emitter.

19. The lighting device of claim 15, wherein any of the first lumiphor and the second lumiphor is located remotely from each of the first solid state emitter and the second solid state emitter.

20. The lighting device of claim 15, further comprising a gap or void arranged between the following items (a) and (b):

(a) at least one of the first lumiphor and the second lumiphor; and

(b) each of the first solid state emitter and the second solid state emitter.

21. The lighting device of claim 15, adapted to provide a color rendering index of greater than 85, and efficiency of greater than 50 lumens per watt.

22. The lighting device of claim 21, exhibiting color stability with respect to temperature in a range of Δ

u′

v′

≦

0.008 over a temperature change of 75°

C.

23. The lighting device of claim 15, characterized by at least one of the following:

any of the first solid state emitter and the second solid state emitter comprises a LED; and

any of the first lumiphor and the second lumiphor comprises a phosphor.

24. A method comprising illuminating an object, a space, or an environment utilizing a lighting device according to claim 15.

25. A lighting device comprising:

at least one solid state emitter having a dominant wavelength of less than or equal to 470 nm, and a plurality of lumiphors arranged to receive emissions from the at least one solid state emitter and responsively output light;

wherein the lighting device is arranged to output a first color peak in a wavelength range of from 430 nm to 470 nm, a second color peak in a wavelength range of from 471 nm to 510 nm, a third color peak within a wavelength range of from 511 nm to 585 nm, and a fourth color peak in a wavelength range of from 600 nm to 650 nm; and

wherein the lighting device provides a color rendering index of greater than 85, provides efficiency of greater than 50 lumens per watt, and exhibits color stability with respect to temperature in a range of Δ

u′

v′

≦

0.008 over a temperature change of 75°

C.

26. The lighting device of claim 25, exhibiting color stability with respect to temperature in a range of Δ

u′

v′

≦

0.004 over a temperature change of 75°

C.

27. The lighting device of claim 25, wherein the at least one solid state emitter comprises a solid state emitter having a dominant wavelength in a range of from 430 nm to 470 nm, and wherein the plurality of lumiphors comprises:

a first lumiphor having a dominant wavelength in a range of from 471 nm to 510 nm;

a second lumiphor having a dominant wavelength in a range of from 511 nm to 585 nm; and

a third lumiphor having a dominant wavelength in a range of from 600 nm to 650 nm.

28. The lighting device of claim 27, being devoid of any additional solid state emitter having a dominant wavelength outside a range of from 430 nm to 470 nm and arranged to contribute to or stimulate spectral output of the lighting device.

29. The lighting device of claim 25, wherein:

the at least one solid state emitter comprises a solid state emitter emitting in the ultraviolet range or the near ultraviolet range;

the plurality of lumiphors comprises;

a first lumiphor having a dominant wavelength in a range of from 430 nm to 470 nm;

a second lumiphor having a dominant wavelength in a range of from 471 nm to 510 nm;

a third lumiphor having a dominant wavelength in a range of from 511 nm to 585 nm; and

a fourth lumiphor having a dominant wavelength in a range of from 600 nm to 650 nm;

each lumiphor is arranged to receive emissions from the at least one solid state emitter, and

spectral output of the lighting device includes in combination at least a portion of emissions from each of the first lumiphor, the second lumiphor, the third lumiphor, and the fourth lumiphor.

30. The lighting device of claim 29, being devoid of any additional solid state emitter emitting outside the ultraviolet range and the near ultraviolet range and arranged to contribute to or stimulate spectral output of the lighting device.

31. The lighting device of claim 25, wherein:

the at least one solid state emitter comprises a first solid state emitter having a dominant wavelength in a range of from 430 nm to 470 nm, and a second solid state emitter having a dominant wavelength in a range of from 471 nm to 510 nm;

the plurality of lumiphors comprises a first lumiphor having a dominant wavelength in a range of from 511 nm to 585 nm, and arranged to interact with at least one of the first solid state emitter and the second solid state emitter to responsively output light; and

the plurality of lumiphors comprises a second lumiphor having a dominant wavelength in a range of from 600 to 650 nm, and arranged to interact with at least one of the first solid state emitter and the second solid state emitter to responsively output light.

32. The lighting device of claim 31, wherein the second solid state emitter has a dominant wavelength in a range of from 471 nm to 484 nm.

33. The lighting device of claim 31, wherein each of the first solid state emitter and the second solid state emitter has a nitride-based active region, and the lighting device is devoid of any additional solid state emitter having a phosphide-based or arsenide-based active region and arranged to contribute to or stimulate spectral output of the lighting device.

34. A method comprising illuminating an object, a space, or an environment utilizing a lighting device according to claim 25.

35. A lighting device comprising:

a plurality of first solid state emitters having a dominant wavelength in a range of from 430 nm to 470 nm;

at least one second solid state emitter having a dominant wavelength in a range of from 471 nm to 510 nm;

a first lumiphor having a dominant wavelength in a range of from 511 nm to 585 nm, and arranged to interact with any of (a) at least one first solid state emitter of the plurality of first solid state emitters and (b) the second solid state emitter, to responsively output light; and

a second lumiphor having a dominant wavelength in a range of from 600 nm to 650 nm, and arranged to interact with any of (a) at least one first solid state emitter of the plurality of solid state emitters and (b) the second solid state emitter, to responsively output light;

wherein radiant flux of the at least one second solid state emitter is in range of less than or equal to about 15% of total radiant flux of the lighting device.

36. The lighting device of claim 35, wherein the at least one second solid state emitter has a dominant wavelength in a range of from 471 nm to 484 nm.

37. The lighting device of claim 35, wherein radiant flux of the at least one second solid state emitter is in range of less than or equal to about 10% of total radiant flux of the lighting device.

38. The lighting device of claim 35, wherein radiant flux of the at least one second solid state emitter is in range of less than or equal to about 6% of total radiant flux of the lighting device.

39. The lighting device of claim 35, wherein each emitter of the plurality of first solid state emitters and the at least one second solid state emitter has a nitride-based active region, and the lighting device is devoid of any additional solid state emitter having a phosphide-based, arsenide-based, or silicide-based active region and arranged to contribute to or stimulate spectral output of the lighting device.

40. The lighting device of claim 35, adapted to provide a color rendering index of greater than 85, and efficiency of greater than 50 lumens per watt.

41. The lighting device of claim 40, exhibiting color stability with respect to temperature in a range of Δ

u′

v′

≦

0.008 over a temperature change of 75°

C.

42. The lighting device of claim 35, characterized by at least one of the following:

the solid state emitter comprises a LED; and

any of the first lumiphor, the second lumiphor, and the third lumiphor comprises a phosphor.

43. A method comprising illuminating an object, a space, or an environment utilizing a lighting device according to claim 35.