High color-saturation lighting devices with enhanced long wavelength illumination

• US 9,530,944 B2
• Filed: 05/01/2015
• Issued: 12/27/2016
• Est. Priority Date: 01/27/2015
• Status: Active Grant

• Current Assignee: IDEAL Industries Lighting, LLC (Ideal Industries Incorporated)
• Original Assignee: CREE Incorporated (Wolfspeed, Inc.)
• Inventors: Jacobson, Benjamin A., Leung, Michael, van de Ven, Antony Paul
• Primary Examiner(s): Dickey, Thomas L
• Application Number:
  US14/702,564
• Publication Number:
  US 20160218254A1
• Time in Patent Office: 606 Days
• US Class Current: 1/1
• CPC Class Codes: F21K 9/232 specially adapted for generating an essentially omnidirectional light distribution, e.g. with a glass bulb
• 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 2115/30 Semiconductor lasers
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/73265 Layer and wire connectors
• CPC Class Codes: H01L 2224/8592 Applying permanent coating, e.g. protective coating
• CPC Class Codes: H01L 25/0753 the devices being arranged next to each other
• CPC Class Codes: H01L 2924/00012 Relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/181 Encapsulation
• CPC Class Codes: H01L 33/504 Elements with two or more wavelength conversion materials

Abstract

A lighting device including a blue solid state emitter, at least one yellow-green or green lumiphoric material, and at least one red or red-orange solid state emitter provides high color saturation, preferably in combination with a high R9-prime (modified R9) color rendering value, with such condition(s) being obtainable with at least one of (i) a red emitter peak wavelength of at least 630 nm, (ii) a green lumiphoric material having a narrow peak wavelength, and (iii) a blue shifted green color point within a specified region of a 1931 CIE chromaticity diagram, and obtainable without requiring a notch filtering material. Aggregate emissions may have a CCT in a range of from 2000K to 5000K.

Claims

1. A lighting device comprising:

at least one first electrically activated solid state emitter arranged to generate first emissions comprising a dominant wavelength in a blue range;

at least one lumiphoric material arranged to receive at least a portion of the first emissions and produce lumiphor emissions comprising a dominant wavelength in a green or yellow-green range; and

at least one second electrically activated solid state emitter arranged to generate second emissions comprising a dominant wavelength in a red or red-orange range;

wherein aggregate emissions of the lighting device include at least a portion of the first emissions, at least a portion of the lumiphor emissions, and at least a portion of the second emissions;

wherein said aggregate emissions comprise a correlated color temperature (CCT) value, and said aggregate emissions comprise a relative gamut area (Qg) value of at least the value obtained by the equation 121 minus the product of 0.003 times the CCT value; and

wherein the lighting device comprises at least one of the following features (a) to (c);

(a) a combination of (A) the lumiphor emissions and (B) an unabsorbed portion of the first emissions transmitted through or past the at least one lumiphoric material would, in the absence of any additional light, produce a mixture of light having a color point on a 1931 CIE Chromaticity Diagram including x, y coordinates that define a point on or within a closed shape bounded by a first line having x, y endpoint coordinates of (0.040, 0.329) and (0.257, 0.345), a second line having x, y endpoint coordinates of (0.257, 0.345) and (0.332, 0.551), a third line having x, y endpoint coordinates of (0.332, 0.551) and (0.020, 0.770), and a curve corresponding to a portion of the spectrum locus having x, y endpoint coordinates of (0.020, 0.770) and (0.040, 0.329);

(b) said aggregate emissions comprise a R9-prime color rendering value that is greater than 110;

or

(c) said aggregate emissions comprise a R9-prime color rendering value that is at least the value obtained by the equation (9 times the Qg value) minus 873, wherein the R9-prime color rendering value is also greater than 100.

2. The lighting device of claim 1, wherein said aggregate emissions comprise a relative gamut area (Qg) value of at least the value obtained by the equation 121 minus the product of 0.003 times the CCT value prior to passage through any optionally present notch filtering element arranged to at least partially inhibit transmission of said aggregate emissions.

3. The lighting device of claim 1, wherein the at least one second electrically activated solid state emitter comprises a peak wavelength of at least 630 nm.

4. The lighting device of claim 1, wherein the at least one lumiphoric material comprises a lumiphor arranged to produce lumiphor emissions having a peak wavelength in a range of from 510 nm to 570 nm and having a full width-half maximum intensity of less than 90 nm.

5. The lighting device of claim 1, wherein the at least one lumiphoric material comprises a lumiphor arranged to produce lumiphor emissions having a peak wavelength in a range of from 510 nm to 544 nm and having a full width-half maximum intensity of less than 80 nm.

6. The lighting device of claim 1, wherein a combination of (A) the lumiphor emissions and (B) an unabsorbed portion of the first emissions transmitted through or past the at least one lumiphoric material would, in the absence of any additional light, produce a mixture of light having a color point on a 1931 CIE Chromaticity Diagram including x, y coordinates that define a point on or within a closed shape bounded by a first line having x, y endpoint coordinates of (0.040, 0.329) and (0.257, 0.345), a second line having x, y endpoint coordinates of (0.257, 0.345) and (0.332, 0.551), a third line having x, y endpoint coordinates of (0.332, 0.551) and (0.020, 0.770), and a curve corresponding to a portion of the spectrum locus having x, y endpoint coordinates of (0.020, 0.770) and (0.040, 0.329).

7. The lighting device of claim 1, wherein said aggregate emissions comprise a R9-prime color rendering value that is greater than 110.

8. The lighting device of claim 1, wherein said aggregate emissions comprise a R9-prime color rendering value that is at least the value obtained by the equation (9 times the Qg value) minus 873, wherein the R9-prime color rendering value is also greater than 100.

9. The lighting device of claim 1, wherein said lighting device is devoid of a notch filtering element arranged to at least partially inhibit transmission of said aggregate emissions.

10. The lighting device of claim 1, wherein said aggregate emissions comprise a correlated color temperature (CCT) value in a range of from 2000K to 6500K.

11. The lighting device of claim 1, wherein said aggregate emissions comprise a Qg value of at least 115.

12. The lighting device of claim 1, wherein said aggregate emissions comprise a R9-prime color rendering value of at least 125.

13. The lighting device of claim 12, wherein said R9-prime color rendering value is at least 175.

14. The lighting device of claim 12, wherein said Qg value is at least 115, and said R9-prime color rendering value is at least 150.

15. The lighting device of claim 1, wherein said aggregate emissions comprise a color point within a 5-step MacAdam ellipse of the blackbody locus on a 1931 CIE Chromaticity Diagram.

16. The lighting device of claim 1, wherein said first emissions comprise a peak wavelength not exceeding 465 nm.

17. The lighting device of claim 1, wherein said second emissions comprise a peak wavelength in a range of from 510 nm to 544 nm.

18. The lighting device of claim 1, wherein said aggregate emissions comprise a CRI Ra value in a range of from 70 to 85.

19. The lighting device of claim 1, wherein said aggregate emissions comprise a CRI Ra value of less than or equal to 80.

20. The lighting device of claim 1, wherein said aggregate emissions of the lighting device comprise a luminous efficacy of at least 80 lumens per watt.

21. The lighting device of claim 1, wherein said aggregate emissions of the lighting device comprise a luminous efficacy of at least 95 lumens per watt.

22. The lighting device of claim 1, wherein:

said at least one lumiphoric material comprises a first lumiphoric material including at least one of lutetium aluminum garnet (LuAG) and green aluminate (GAL) material; and

said at least one lumiphoric material comprises a second lumiphoric material including cerium(III)-doped yttrium aluminum garnet (Ce;

YAG) material;

wherein a proportion of the first lumiphoric material to the second lumiphoric material is at least 1;

1.

23. The lighting device of claim 22, wherein a proportion of the first lumiphoric material to the second lumiphoric material is at least 1.5:

1.

24. The lighting device of claim 22, wherein a proportion of the first lumiphoric material to the second lumiphoric material is at least 2:

1.

25. The lighting device of claim 1, further comprising a first power line, wherein each of the at least one first electrically activated solid state emitter and the at least one second electrically activated solid state emitter is electrically connected to the first power line.

26. The lighting device of claim 1, comprising at least one of the following features:

a single leadframe arranged to conduct electrical power to the at least one first electrically activated solid state emitter and the at least one second electrically activated solid state emitter;

a single reflector arranged to reflect at least a portion of light emanating from each of the at least one first electrically activated solid state emitter and the at least one second electrically activated solid state emitter;

a single submount or mounting element supporting the at least one first electrically activated solid state emitter and the at least one second electrically activated solid state emitter;

a single lens arranged to transmit at least a portion of light emanating from each of the at least one first electrically activated solid state emitter and the at least one second electrically activated solid state emitter;

or

a single diffuser arranged to diffuse at least a portion of light emanating from each of the at least one first electrically activated solid state emitter and the at least one second electrically activated solid state emitter.

27. The lighting device of claim 1, wherein the at least one first electrically activated solid state emitter comprises a plurality of first electrically activated solid state emitters, and the at least one second electrically activated solid state emitter comprises a plurality of second electrically activated solid state emitters.

28. The lighting device of claim 27, comprising a plurality of clusters of solid state emitters, wherein each cluster of the plurality of clusters includes at least one electrically activated solid state emitter of the plurality of first electrically activated solid state emitters and at least one electrically activated solid state emitter of the plurality of second electrically activated solid state emitters.

29. The lighting device of claim 1, being devoid of any electrically activated solid state emitter arranged to generate emissions (i) having a dominant wavelength in a range of from 430 nm to 480 nm and (ii) exiting the lighting device without passage through a layer or region comprising a lumiphoric material.

30. The lighting device of claim 1, being devoid of any incandescent light emitting element.

31. A light bulb or light fixture comprising the lighting device of claim 1.

32. A lighting device comprising:

at least one first electrically activated solid state emitter arranged to generate first emissions comprising a dominant wavelength in a blue range;

at least one lumiphoric material arranged to receive at least a portion of the first emissions and produce lumiphor emissions comprising a dominant wavelength in a green or yellow range; and

at least one second electrically activated solid state emitter arranged to generate second emissions comprising a dominant wavelength in a red or red-orange range;

wherein aggregate emissions of the lighting device include at least a portion of the first emissions, at least a portion of the lumiphor emissions, and at least a portion of the second emissions;

wherein said lighting device is devoid of a notch filtering element arranged to at least partially inhibit transmission of said aggregate emissions; and

wherein said aggregate emissions comprise a correlated color temperature (CCT) value, and said aggregate emissions comprise a relative gamut area (Qg) value of at least the value obtained by the equation 121 minus the product of 0.003 times the CCT value; and

wherein the lighting device comprises at least one of the following features (a) to (c);

(a) a combination of (A) the lumiphor emissions and (B) an unabsorbed portion of the first emissions transmitted through or past the at least one lumiphoric material would, in the absence of any additional light, produce a mixture of light having a color point on a 1931 CIE Chromaticity Diagram including x, y coordinates that define a point on or within a closed shape bounded by a first line having x, y endpoint coordinates of (0.040, 0.329) and (0.257, 0.345), a second line having x, y endpoint coordinates of (0.257, 0.345) and (0.332, 0.551), a third line having x, y endpoint coordinates of (0.332, 0.551) and (0.020, 0.770), and a curve corresponding to a portion of the spectrum locus having x, y endpoint coordinates of (0.020, 0.770) and (0.040, 0.329);

(b) said aggregate emissions comprise a R9-prime color rendering value that is greater than 110;

or

(c) said aggregate emissions comprise a R9-prime color rendering value that is at least the value obtained by the equation (9 times the Qg value) minus 873, wherein the R9-prime color rendering value is also greater than 100.

33. A lighting device comprising:

at least one first electrically activated solid state emitter arranged to generate first emissions comprising a dominant wavelength in a blue range;

at least one first lumiphoric material arranged to receive at least a portion of the first emissions and produce first lumiphor emissions comprising a dominant wavelength in a green or yellow-green range; and

at least one second lumiphoric material arranged to receive at least a portion of the first emissions and produce second lumiphor emissions comprising a dominant wavelength in a red range;

wherein aggregate emissions of the lighting device include at least a portion of the first emissions, at least a portion of the first lumiphor emissions, and at least a portion of the second lumiphor emissions;

wherein said aggregate emissions comprise a correlated color temperature (CCT) value; and

wherein the lighting device comprises one of the following features (i) and (ii);

(i) the at least one second lumiphoric material comprises a phosphor arranged to produce lumiphor emissions having at least one peak wavelength in a range of from 620 nm to 650 nm and a full width-half maximum intensity value of less than 60 nm, and said aggregate emissions comprise a relative gamut area (Qg) value of at least the value obtained by the equation 127.35 minus the product of 0.0058 times the CCT value prior to passage through an optionally present notch filtering element arranged to at least partially inhibit transmission of said aggregate emissions;

or

(ii) the at least one second lumiphoric material comprises a red quantum dot material arranged to produce lumiphor emissions having a peak wavelength in a range of from 620 nm to 650 nm, and said aggregate emissions comprise a relative gamut area (Qg) value of at least 110 prior to passage through an optionally present notch filtering element arranged to at least partially inhibit transmission of said aggregate emissions.

34. The lighting device of claim 33, wherein the at least one second lumiphoric material is arranged to produce lumiphor emissions having a peak wavelength in a range of from 625 nm to 645 nm.

35. The lighting device of claim 33, comprising feature (i).

36. The lighting device of claim 35, wherein the phosphor is arranged to produce emissions including multiple peak wavelengths in a range of from 620 nm to 650 nm, wherein each peak wavelength of the multiple peak wavelengths includes a full width-half maximum intensity value of less than 20 nm.

37. The lighting device of claim 33, comprising feature (ii).

38. The lighting device of claim 37, wherein said aggregate emissions comprise a relative gamut area (Qg) value of at least the value obtained by the equation 129.35 minus the product of 0.0058 times the CCT value.

39. The lighting device of claim 33, wherein said aggregate emissions embody a color rendering index value of at least 80.

40. A light bulb comprising:

a lighting device according to claim 33, embodied in an emitter package including the at least one first electrically activated solid state emitter, the at least one first lumiphoric material, and the at least one second lumiphoric material; and

a light-transmissive optical enclosure bounded by a light-transmissive lens or globe and containing the lighting device.