High CRI lighting device with added long-wavelength blue color

• US 8,508,117 B2
• Filed: 02/18/2011
• Issued: 08/13/2013
• Est. Priority Date: 03/09/2010
• Status: Active Grant

• Current Assignee: Creeled Incorporated
• Original Assignee: CREE Incorporated (Wolfspeed, Inc.)
• Inventors: Negley, Gerald H., van de Ven, Antony Paul, Keller, Bernd P., LeToquin, Ronan P., Andrews, Peter Scott
• Primary Examiner(s): Williams, Joseph L
• Application Number:
  US13/030,421
• Publication Number:
  US 20110222277A1
• Time in Patent Office: 907 Days
• Field of Search: 313498-512, 313483-486, 362/231
• 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 devices 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:

at least one electrically activated first solid state emitter having a first dominant wavelength in a range of from 430 nm to 470 nm;

at least one electrically activated second solid state emitter having a second dominant wavelength in a range of from 471 nm to 493 nm;

at least one electrically activated third solid state emitter having a third dominant wavelength in a range of from 600 nm to 650 nm; and

at least one lumiphor overlying, located remotely from, and arranged to receive emissions from any of the at least one first solid state emitter and the at least one second solid state emitter, and to responsively emit light having a fourth dominant wavelength that differs from the first, second, and third dominant wavelength;

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

2. The lighting device of claim 1, wherein the at least one second solid state emitter has a second dominant wavelength in a range of from 471 nm to 484 nm.

3. The lighting device of claim 1, wherein the at least one lumiphor has a fourth dominant wavelength in a range of from 511 nm to 585 nm.

4. The lighting device of claim 1, wherein the at least one lumiphor has a fourth dominant wavelength in a range of from 555 nm to 585 nm.

5. The lighting device of claim 1, wherein the at least one lumiphor has a fourth dominant wavelength in a range of from 471 nm to 510 nm.

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

7. The lighting device of claim 1, wherein each solid state emitter comprises a LED, and the at least one lumiphor comprises a phosphor.

8. The lighting device of claim 1, wherein the at least one first solid state emitter, the at least one second solid state emitter, and the at least one third solid state emitter are disposed on or over a common submount.

9. The lighting device of claim 1, wherein the at least one first solid state emitter, the at least one second solid state emitter, and the at least one third solid state emitter are connected to a common leadframe.

10. The lighting device of claim 1, wherein the at least one first solid state emitter, the at least one second solid state emitter, and the at least one third solid state emitter are arranged to emit light for reflection by a common reflector.

11. The lighting device of claim 1, wherein the at least one lumiphor comprises a first lumiphor and a second lumiphor, and any of the first lumiphor and the second lumiphor is disposed relative to the at least one first solid state emitter and the at least one second solid state emitter in a quantity or concentration that differs with respect to the at least one first solid state emitter and the at least one second solid state emitter.

12. The lighting device of claim 1, 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.

13. The lighting device of claim 1, 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.

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

15. The lighting device of claim 1, wherein the at least one first solid state emitter comprises a plurality of first solid state emitters.

16. The lighting device of claim 1, wherein the at least one second solid state emitter comprises a plurality of second solid state emitters.

17. The lighting device of claim 1, wherein the at least one lumiphor comprises a first lumiphor and a second lumiphor, and wherein the first lumiphor comprises a peak wavelength that differs from a peak wavelength of the second lumiphor.

18. The lighting device of claim 17, wherein the first lumiphor is arranged in a first discrete layer, and the second lumiphor is arranged in a second discrete layer.

19. The lighting device of claim 1, wherein the at least one lumiphor is spatially separated from each of the at least one first solid state emitter, the at least one second solid state emitter, and the at least one third solid state emitter by a distance of at least 0.5 mm.

20. The lighting device of claim 1, further comprising an encapsulant material arranged between the at least one lumiphor and any of the at least one first solid state emitter, the at least one second solid state emitter, and the at least one third solid state emitter.