Lighting device providing improved color rendering
View Patent ↗The present disclosure relates to lighting device configurations that render colors well and provide high quality white light.
1. A lighting device comprising:
a first plurality of solid-state light emitters wherein each of the first plurality of solid-state light emitters is associated with a wavelength conversion material;
a second plurality of solid-state light emitters; and
current control circuitry adapted to provide current to the first and second pluralities of solid-state light emitters such that:
a peak wavelength of excitation light emitted by the first plurality of solid-state light emitters is from 410 nm to 490 nm;
a dominant wavelength of light emitted by the wavelength conversion material is from 535 nm to 590 nm when excited by the excitation light emitted by the first plurality of solid-state light emitters; and
a dominant wavelength of light emitted by the second plurality of solid-state light emitters is from 631 nm to 700 nm, wherein a combination of light emitted by the first and second pluralities of solid-state light emitters and the wavelength conversion material produces white light at a color point on a 1931 CIE chromaticity diagram within ten MacAdam ellipses of a black body locus.
2. The lighting device of claim 1 wherein the wavelength conversion material is a yellow phosphor that emits yellowish light when excited by the excitation light and each of the first plurality of solid-state light emitters is a blue-shifted yellow (BSY) light emitting diode (LED) comprising a blue LED chip that emits bluish light and is associated with the yellow phosphor.
3. The lighting device of claim 2 wherein the combination of light emitted by the first plurality of solid-state light emitters and the wavelength conversion material produces light having a color point on the 1931 CIE chromaticity diagram that falls within a color space defined by a set of points with x, y coordinates: (0.29, 0.36), (0.38, 0.53), (0.44,0.49), (0.41, 0.43), and (0.32, 0.35).
4. The lighting device of claim 2 wherein the combination of light emitted by the first plurality of solid-state light emitters and the wavelength conversion material produces light having a color point on the 1931 CIE chromaticity diagram that falls within a color space defined by a set of points with x, y coordinates: (0.32, 0.40), (0.36, 0.48), (0.43,0.45), (0.42, 0.42), and (0.36, 0.38).
5. The lighting device of claim 2 wherein the dominant wavelength of light emitted by the second plurality of solid-state light emitters is from 641 nm to 700 nm.
6. The lighting device of claim 2 wherein the dominant wavelength of light emitted by the second plurality of solid-state light emitters is from 641 nm to 680 nm.
7. The lighting device of claim 2 wherein the dominant wavelength of light emitted by the wavelength conversion material is from 566 nm to 585 nm when excited by the excitation light emitted by the first plurality of solid-state light emitters and the dominant wavelength of light emitted by the second plurality of solid-state light emitters is from 631 nm to 680 nm.
8. The lighting device of claim 2 wherein the dominant wavelength of light emitted by the wavelength conversion material is from 566 nm to 585 nm when excited by the excitation light emitted by the first plurality of solid-state light emitters and the dominant wavelength of light emitted by the second plurality of solid-state light emitters is from 641 nm to 680 nm.
9. The lighting device of claim 2 wherein the peak wavelength of excitation light emitted by the first plurality of solid-state light emitters is from 430 nm to 480 nm; the dominant wavelength of light emitted by the wavelength conversion material is from 566 nm to 585 nm when excited by the excitation light emitted by the first plurality of solid-state light emitters; and the dominant wavelength of light emitted by the second plurality of solid-state light emitters is from 641 nm to 680 nm.
10. The lighting device of claim 1 wherein the wavelength conversion material is a green phosphor that emits greenish light when excited by the excitation light and each of the first plurality of solid-state light emitters is a blue-shifted green (BSG) light emitting diode (LED) comprising a blue LED chip that emits bluish light and is associated with the green phosphor.
11. The lighting device of claim 10 wherein the combination of light emitted by the first plurality of solid-state light emitters and the wavelength conversion material produces light having a color point on the 1931 CIE chromaticity diagram that falls within a color space defined by a set of points with x, y coordinates: (0.13, 0.26), (0.35, 0.48), (0.26,0.50), and (0.15, 0.20).
12. The lighting device of claim 10 wherein the combination of light emitted by the first plurality of solid-state light emitters and the wavelength conversion material produces light having a color point on the 1931 CIE chromaticity diagram that falls within a color space defined by a set of points with x, y coordinates: (0.21, 0.28), (0.28, 0.44), (0.32,0.42), and (0.26, 0.28).
13. The lighting device of claim 1 wherein the white light has a color quality scale measurement equal to or greater than 90.
14. The lighting device of claim 1 wherein the white light has a color quality scale measurement equal to or greater than 90 and a color rendering index Ra equal to or greater than 90.
15. The lighting device of claim 1 wherein the white light has a color quality scale measurement equal to or greater than 85.
16. The lighting device of claim 1 wherein the white light has a color quality scale measurement equal to or greater than 85 and a color rendering index Ra equal to or greater than 85.
17. The lighting device of claim 1 wherein the white light has a color quality scale measurement equal to or greater than 90 and a color rendering index Ra less than 90.
18. The lighting device of claim 1 wherein the white light has a color quality scale measurement equal to or greater than 85 and a color rendering index Ra less than 85.
19. A lighting device comprising:
a first plurality of solid-state light emitters wherein each of the first plurality of solid-state light emitters is associated with a wavelength conversion material;
a second plurality of solid-state light emitters; and
current control circuitry adapted to provide current to the first and second pluralities of solid-state light emitters such that a combination of light emitted by the first and second pluralities of solid-state light emitters and the wavelength conversion material produces white light at a color point on a 1931 CIE chromaticity diagram within ten MacAdam ellipses of a black body locus and having a color quality scale measurement equal to or greater than 85.
20. The lighting device of claim 19 wherein:
a peak wavelength of excitation light emitted by the first plurality of solid-state light emitters is from 410 nm to 490 nm;
a dominant wavelength of light emitted by the wavelength conversion material is from 535 nm to 590 nm when excited by the excitation light emitted by the first plurality of solid-state light emitters; and
a dominant wavelength of light emitted by the second plurality of solid-state light emitters is from is 590 nm to 700 nm.
21. The lighting device of claim 20 wherein the peak wavelength of excitation light emitted by the first plurality of solid-state light emitters is from 445 nm to 470 nm; the dominant wavelength of light emitted by the wavelength conversion material is from 566 nm to 575 nm when excited by the excitation light emitted by the first plurality of solid-state light emitters; and the dominant wavelength of light emitted by the second plurality of solid-state light emitters is from 605 nm to 650 nm.
22. The lighting device of claim 21 wherein the white light has a color quality scale measurement equal to or greater than 90.
23. The lighting device of claim 22 wherein the white light has a color temperature between about 2700K and 4000K.
24. The lighting device of claim 20 wherein the peak wavelength of excitation light emitted by the first plurality of solid-state light emitters is from 448 nm to 468 nm; the dominant wavelength of light emitted by the wavelength conversion material is from 568 nm to 573 nm when excited by the excitation light emitted by the first plurality of solid-state light emitters; and the dominant wavelength of light emitted by the second plurality of solid-state light emitters is from 615 nm to 645 nm.
25. The lighting device of claim 24 wherein the white light has a color quality scale measurement equal to or greater than 90.
26. The lighting device of claim 25 wherein the white light has a color temperature between about 2700K and 4000K.
27. The lighting device of claim 20 wherein the peak wavelength of excitation light emitted by the first plurality of solid-state light emitters is from 430 nm to 480 nm; the dominant wavelength of light emitted by the wavelength conversion material is from 560 nm to 580 nm when excited by the excitation light emitted by the first plurality of solid-state light emitters; and the dominant wavelength of light emitted by the second plurality of solid-state light emitters is from 605 nm to 660 nm.
28. The lighting device of claim 27 wherein the white light has a color temperature between about 2700K and 4000K.
29. The lighting device of claim 20 wherein the peak wavelength of excitation light emitted by the first plurality of solid-state light emitters is from 430 nm to 480 nm; the dominant wavelength of light emitted by the wavelength conversion material is from 540 nm to 560 nm when excited by the excitation light emitted by the first plurality of solid-state light emitters; and the dominant wavelength of light emitted by the second plurality of solid-state light emitters is from 605 nm to 640 nm.
30. The lighting device of claim 29 wherein the white light has a color temperature between about 4000K and 6500K.
31. The lighting device of claim 30 wherein the white light has a color quality scale measurement equal to or greater than 90.
32. The lighting device of claim 20 wherein the peak wavelength of excitation light emitted by the first plurality of solid-state light emitters is from 430 nm to 470 nm; the dominant wavelength of light emitted by the wavelength conversion material is from 540 nm to 560 nm when excited by the excitation light emitted by the first plurality of solid-state light emitters; and the dominant wavelength of light emitted by the second plurality of solid-state light emitters is from 609 nm to 630 nm.
33. The lighting device of claim 32 wherein the white light has a color temperature between about 4000K and 6500K.
34. The lighting device of claim 33 wherein the white light has a color quality scale measurement equal to or greater than 90.
35. The lighting device of claim 20 wherein the peak wavelength of excitation light emitted by the first plurality of solid-state light emitters is from 420 nm to 480 nm; the dominant wavelength of light emitted by the wavelength conversion material is from 540 nm to 560 nm when excited by the excitation light emitted by the first plurality of solid-state light emitters; and the dominant wavelength of light emitted by the second plurality of solid-state light emitters is from 590 nm to 660 nm.
36. The lighting device of claim 35 wherein the white light has a color temperature between about 4000K and 6500K.
37. The lighting device of claim 20 wherein the white light has a color quality scale measurement equal to or greater than 90 and a color rendering index Ra equal to or greater than 90.
38. The lighting device of claim 20 wherein the white light has a color rendering index Ra equal to or greater than 85.
39. The lighting device of claim 20 wherein the white light has a color quality scale measurement equal to or greater than 90 and a color rendering index Ra less than 20.
40. The lighting device of claim 20 wherein the white light has a color quality scale measurement equal to or greater than 85 and a color rendering index Ra less than 85.
41. The lighting device of claim 20 wherein the white light has a color quality scale measurement equal to or greater than 90.
42. The lighting device of claim 41 wherein the wavelength conversion material is a green phosphor that emits greenish light when excited by the excitation light and each of the first plurality of solid-state light emitters is a blue-shifted green (BSG) light emitting diode (LED) comprising a blue LED chip that emits bluish light and is associated with the green phosphor.
43. The lighting device of claim 42 wherein the combination of light emitted by the first plurality of solid-state light emitters and the wavelength conversion material produces light having a color point on the 1931 CIE chromaticity diagram that falls within a color space defined by a set of points with x, y coordinates: (0.13, 0.26), (0.35, 0.48), (0.26,0.50), and (0.15, 0.20).
44. The lighting device of claim 42 wherein the combination of light emitted by the first plurality of solid-state light emitters and the wavelength conversion material produces light having a color point on the 1931 CIE chromaticity diagram that falls within a color space defined by a set of points with x, y coordinates: (0.21, 0.28), (0.28, 0.44), (0.32,0.42), and (0.26, 0.28).
45. The lighting device of claim 41 wherein the wavelength conversion material is a yellow phosphor that emits yellowish light when excited by the excitation light and each of the first plurality of solid-state light emitters is a blue-shifted yellow (BSY) light emitting diode (LED) comprising a blue LED chip that emits bluish light and is associated with the yellow phosphor.
46. The lighting device of claim 45 wherein the combination of light emitted by the first plurality of solid-state light emitters and the wavelength conversion material produces light having a color point on the 1931 CIE chromaticity diagram that falls within a color space defined by a set of points with x, y coordinates: (0.29, 0.36), (0.38, 0.53), (0.44,0.49), (0.41, 0.43), and (0.32, 0.35).
47. The lighting device of claim 45 wherein the combination of light emitted by the first plurality of solid-state light emitters and the wavelength conversion material produces light having a color point on the 1931 CIE chromaticity diagram that falls within a color space defined by a set of points with x, y coordinates: (0.32, 0.40), (0.36, 0.48), (0.43,0.45), (0.42, 0.42), and (0.36, 0.38).
48. The lighting device of claim 19 wherein the combination of light emitted by the first plurality of solid-state light emitters and the wavelength conversion material produces light having a color point on the 1931 CIE chromaticity diagram that falls within a color space defined by a set of points with x, y coordinates: (0.59, 0.24) (0.40, 0.50) (0.24, 0.53) (0.17, 0.25) and (0.30, 0.12).
49. The lighting device of claim 19 wherein the combination of light emitted by the first plurality of solid-state light emitters and the wavelength conversion material produces light having a color point on the 1931 CIE chromaticity diagram that falls within a color space defined by a set of points with x, y coordinates: (0.41, 0.45) (0.37, 0.47) (0.25, 0.27) and (0.29, 0.24).