SOLID STATE ILLUMINATION SYSTEM WITH IMPROVED COLOR QUALITY

• US 20090122530A1
• Filed: 12/30/2008
• Published: 05/14/2009
• Est. Priority Date: 10/17/2007
• Status: Active Grant

• Current Assignee: Savant Technologies, LLC (Savant Systems, LLC)
• Original Assignee: General Electric Company
• Inventors: BEERS, William Winder, Allen, Gary Robert
• Granted Patent: US 8,247,959 B2
• Time in Patent Office: Days
• US Class Current: 362/230
• CPC Class Codes: F21K 9/00 Light sources using semiconductor devices as light-generating elements, e.g. using light-emitting diodes [LED] or lasers

Abstract

Disclosed herein are solid state illumination systems which provide improved color quality and/or color contrast. The systems provide total light having delta chroma values for each of the fifteen color samples of the color quality scale that are preselected to provide enhanced color contrast relative to an incandescent or blackbody light source, in accordance with specified values which depend on color temperature. Illumination systems provided herein may comprise one or more organic electroluminescent element, or they may comprise a plurality of inorganic light emitting diodes, wherein at least two inorganic light emitting diodes have different color emission bands. Methods for the manufacture of illumination systems having improved color quality and/or color contrast are also provided.

Claims

1. An illumination system which, when energized, exhibits a correlated color temperature (CCT) in the range of between about 2000 K and about 20000 K, the system comprising:

one or more organic electroluminescent element;

wherein said system is configured to provide a total light that appears white when energized, said total light having delta chroma values for each of the fifteen color samples of the color quality scale (CQS) that are preselected to provide enhanced color contrast relative to an incandescent or blackbody light source, in accordance with the following;

(A) for a system having a CCT in the range of between about 2000 K and about 3000 K, the delta chroma values are as follows;

at least two color samples of the CQS are within the parameters

−

2 to 7 for VS1;

−

3 to 7 for VS2;

−

7 to 7 for VS3;

at least one color sample of the CQS is within the parameters

−

2 to 8 for VS4;

−

2 to 15 for VS5;

at least two color samples of the CQS are within the parameters

1 to 25 for VS6;

4 to 26 for VS7;

−

1 to 15 for VS8;

at least two color samples of the CQS are within the parameters

−

6 to 7 for VS9;

−

4 to 6 for VS10;

−

2 to 8 for VS1;

at least one color sample of the CQS is within the parameters

1 to 8 for VS12;

−

1 to 13 for VS13; and

at least one color sample of the CQS is within the parameters

−

7 to 13 for VS14;

−

9 to 12 for VS15;

(B) for a system having a CCT in the range of between about 3000 K and about 4500 K, the delta chroma values are as follows;

at least two color samples of the CQS are within the parameters

−

5 to 7 for VS1;

−

3 to 7 for VS2;

−

7 to 7 for VS3;

at least one color sample of the CQS is within the parameters

−

3 to 8 for VS4;

−

2 to 15 for VS5;

at least two color samples of the CQS are within the parameters

0 to 22 for VS6;

3 to 26 for VS7;

−

1 to 15 for VS8;

at least two color samples of the CQS are within the parameters

−

6 to 7 for VS9;

−

4 to 6 for VS10;

−

4 to 6 for VS11;

at least one color sample of the CQS is within the parameters

−

1 to 8 for VS12;

−

1 to 13 for VS13; and

at least one color sample of the CQS is within the parameters

−

7 to 15 for VS14;

−

7 to 12 for VS15;

(C) for a system having a CCT in the range of between about 4500 K and about 7500 K, the delta chroma values are as follows;

at least two color samples of the CQS are within the parameters

−

5 to 7 for VS1;

−

3 to 7 for VS2;

−

5 to 7 for VS3;

at least one color sample of the CQS is within the parameters

−

3 to 7 for VS4;

−

2 to 15 for VS5;

at least two color samples of the CQS are within the parameters

0 to 22 for VS6;

1 to 26 for VS7;

−

1 to 15 for VS8;

at least two color samples of the CQS are within the parameters

−

6 to 7 for VS9;

−

5 to 6 for VS10;

−

4 to 6 for VS11;

at least one color sample of the CQS is within the parameters

−

2 to 8 for VS12;

−

1 to 16 for VS13; and

at least one color sample of the CQS is within the parameters

−

5 to 22 for VS14;

−

6 to 15 for VS15,

(D) for a system having a CCT in the range of between about 7500 K and about 20000 K, the delta chroma values are as follows;

at least two color samples of the CQS are within the parameters

−

3 to 7 for VS1;

−

3 to 7 for VS2;

−

5 to 8 for VS3;

at least one color sample of the CQS is within the parameters

−

3 to 6 for VS4;

−

3 to 15 for VS5;

at least two color samples of the CQS are within the parameters

0 to 22 for VS6;

0 to 25 for VS7;

−

1 to 15 for VS8;

at least two color samples of the CQS are within the parameters

−

5 to 7 for VS9;

−

5 to 6 for VS10;

−

4 to 6 for VS1;

at least one color sample of the CQS is within the parameters

−

3 to 8 for VS12;

−

1 to 16 for VS13; and

at least one color sample of the CQS is within the parameters

−

3 to 24 for VS14;

−

4 to 15 for VS15;

wherein all delta chroma values are measured in the CIE LAB space.

2. The illumination system in accordance with claim 1, wherein the delta chroma values are preselected in accordance with the following:

(A) for a system having a CCT in the range of between about 2000 K and about 3000 K, the delta chroma values are as follows;

at least two color samples of the CQS are within the parameters

0 to 5 for VS1;

−

1 to 5 for VS2;

−

5 to 5 for VS3;

at least one color sample of the CQS is within the parameters

0 to 7 for VS4;

0 to 14 for VS5;

at least two color samples of the CQS are within the parameters

3 to 20 for VS6;

5 to 25 for VS7;

2 to 10 for VS8;

at least two color samples of the CQS are within the parameters

−

2.5 to 5 for VS9;

−

2.5 to 5 for VS10;

0 to 5 for VS1;

at least one color sample of the CQS is within the parameters

0 to 6 for VS12;

2 to 10 for VS13; and

at least one color sample of the CQS is within the parameters

2 to 10 for VS14;

2 to 10 for VS15;

(B) for a system having a CCT in the range of between about 3000 K and about 4500 K, the delta chroma values are as follows;

at least two color samples of the CQS are within the parameters

0 to 5 for VS1;

−

1 to 5 for VS2;

−

5 to −

5 for VS3;

at least one color sample of the CQS is within the parameters

0 to 7 for VS4;

0 to 14 for VS5;

at least two color samples of the CQS are within the parameters

3 to 20 for VS6;

5 to 25 for VS7;

2 to 11 for VS8;

at least two color samples of the CQS are within the parameters

2.5 to 5 for VS9;

−

2.5 to 5 for VS10;

0 to 5 for VS1;

at least one color sample of the CQS is within the parameters

0 to 6 for VS12;

2 to 10 for VS13; and

at least one color sample of the CQS is within the parameters

2 to 12 for VS14;

2 to 11 for VS15;

(C) for a system having a CCT in the range of between about 4500 K and about 7500 K, the delta chroma values are as follows;

at least two color samples of the CQS are within the parameters

0 to 5 for VS1;

−

1 to 5 for VS2;

−

3 to 5 for VS3;

at least one color sample of the CQS is within the parameters

−

1 to 5 for VS4;

0 to 10 for VS5;

at least two color samples of the CQS are within the parameters

3 to 15 for VS6;

5 to 18 for VS7;

2 to 12 for VS8;

at least two color samples of the CQS are within the parameters

−

2.5 to 5 for VS9;

−

2.5 to 5 for VS10;

−

2 to 5 for VS11;

at least one color sample of the CQS is within the parameters

0 to 6 for VS12;

2 to 10 for VS13; and

at least one color sample of the CQS is within the parameters

2 to 12 for VS14;

0 to 11 for VS15;

(D) for a system having a CCT in the range of between about 7500 K and about 20000 K, the delta chroma values are as follows;

at least two color samples of the CQS are within the parameters

0 to 5 for VS1;

−

1 to 5 for VS2;

−

2 to 7 for VS3;

at least one color sample of the CQS is within the parameters

−

1 to 4 for VS4;

0 to 10 for VS5;

at least two color samples of the CQS are within the parameters

3 to 15 for VS6;

5 to 16 for VS7;

2 to 12 for VS8;

at least two color samples of the CQS are within the parameters

0 to 5 for VS9;

−

2 to 5 for VS10;

−

3 to 5 for VS11;

at least one color sample of the CQS is within the parameters

0 to 6 for VS12;

1 to 10 for VS13; and

at least one color sample of the CQS is within the parameters

2 to 11 for VS14;

0 to 11 for VS15.

3. The illumination system of claim 1, further comprising a substrate for supporting said one or more organic electroluminescent element.

4. The illumination system of claim 3, wherein said substrate comprises a heat dissipating element capable of dissipating heat from said system.

5. The illumination system of claim 1, wherein said system further includes leads for providing electric current to the one or more organic electroluminescent element.

6. The illumination system of claim 1, said system further including at least one controller and at least one processor, wherein said at least one processor is configured to receive a signal from said controller to control intensity of emission from said one or more organic electroluminescent element.

7. The illumination system of claim 6, wherein said at least one controller is in communication with a sensor receptive to one or more of total light emission and temperature of said one or more organic electroluminescent element.

8. The illumination system of claim 6, wherein said at least one processor controls electric current to said one or more organic electroluminescent element.

9. The illumination system of claim 1, wherein said one or more organic electroluminescent element is at least partially enclosed by a transparent or translucent envelope.

10. The illumination system of claim 1, said system further comprising an optical facility configured to perform at least one light-affecting operation upon light emitted from said one or more organic electroluminescent element, said operation selected from the group consisting of mixing, scattering, attenuating, guiding, extracting, controlling, reflecting, refracting, diffracting, polarizing, and beam-shaping.

11. The illumination system of claim 10, wherein said optical facility includes a scattering element or optical diffuser to mix light.

12. The illumination system of claim 11, wherein said scattering element or optical diffuser is selected from at least one of film, particle, diffuser, prism, and mixing plate.

13. The illumination system of claim 10, wherein said optical facility includes a light guiding or shaping element selected from lens, filter, iris, and collimator.

14. The illumination system of claim 10, wherein said optical facility includes an encapsulant for said one or more organic electroluminescent element, configured to scatter or diffuse light.

15. The illumination system of claim 10, wherein said optical facility includes a reflector, or a refractive or total-internal-reflective light guide.

16. The illumination system of claim 1, wherein said one or more organic electroluminescent element comprises an electroluminescent organic molecule or an electroluminescent polymer.

17. The illumination system of claim 16, wherein said one or more organic electroluminescent element is arranged in a device comprising an active layer sandwiched between electrodes.

18. The illumination system of claim 1, comprising a plurality of active layers of said one or more organic electroluminescent element, said plurality arranged in a stacked or overlaid configuration.

19. The illumination system of claim 1, wherein said system comprises at least one filter for modifying the combined light.

20. The illumination system of claim 1, wherein said system comprises at least one photoluminescent material selected from phosphor, quantum dot, and combinations thereof, for converting light from said one or more organic electroluminescent element to a different wavelength.

21. The illumination system of claim 1, wherein said system comprises at least one inorganic light emitting diode.

22. An illumination system which, when energized, exhibits a correlated color temperature (CCT) in the range of between about 2000 K and about 20000 K, the system comprising:

a plurality of inorganic light emitting diodes, wherein at least two inorganic light emitting diodes have different color emission bands;

wherein said system is configured to provide a total light that appears white when energized, said total light having delta chroma values for each of the fifteen color samples of the color quality scale (CQS) that are preselected to provide enhanced color contrast relative to an incandescent or blackbody light source, in accordance with the following;

(A) for a system having a CCT in the range of between about 2000 K and about 3000 K, the delta chroma values are as follows;

at least two color samples of the CQS are within the parameters

−

2 to 7 for VS1;

−

3 to 7 for VS2;

−

7 to 7 for VS3;

at least one color sample of the CQS is within the parameters

−

2 to 8 for VS4;

−

2 to 15 for VS5;

at least two color samples of the CQS are within the parameters

1 to 25 for VS6;

4 to 26 for VS7;

−

1 to 15 for VS8;

at least two color samples of the CQS are within the parameters

−

6 to 7 for VS9;

−

4 to 6 for VS10;

−

2 to 8 for VS11;

at least one color sample of the CQS is within the parameters

−

1 to 8 for VS12;

−

1 to 13 for VS13; and

at least one color sample of the CQS is within the parameters

−

7 to 13 for VS14;

−

9 to 12 for VS15;

(B) for a system having a CCT in the range of between about 3000 K and about 4500 K, the delta chroma values are as follows;

at least two color samples of the CQS are within the parameters

−

5 to 7 for VS1;

−

3 to 7 for VS2;

−

7 to 7 for VS3;

at least one color sample of the CQS is within the parameters

−

3 to 8 for VS4;

−

2 to 15 for VS5;

at least two color samples of the CQS are within the parameters

0 to 22 for VS6;

3 to 26 for VS7;

−

1 to 15 for VS8;

at least two color samples of the CQS are within the parameters

−

6 to 7 for VS9;

−

4 to 6 for VS10;

−

4 to 6 for VS11;

at least one color sample of the CQS is within the parameters

−

1 to 8 for VS12;

−

1 to 13 for VS13; and

at least one color sample of the CQS is within the parameters

−

7 to 15 for VS14;

−

7 to 12 for VS15;

(C) for a system having a CCT in the range of between about 4500 K and about 7500 K, the delta chroma values are as follows;

at least two color samples of the CQS are within the parameters

−

5 to 7 for VS1;

−

3 to 7 for VS2;

−

5 to 7 for VS3;

at least one color sample of the CQS is within the parameters

−

3 to 7 for VS4;

−

2 to 15 for VS5;

at least two color samples of the CQS are within the parameters

0 to 22 for VS6;

1 to 26 for VS7;

−

1 to 15 for VS8;

at least two color samples of the CQS are within the parameters

−

6 to 7 for VS9;

−

5 to 6 for VS10;

4 to 6 for VS11;

at least one color sample of the CQS is within the parameters

−

2 to 8 for VS12;

−

1 to 16 for VS13; and

at least one color sample of the CQS is within the parameters

−

5 to 22 for VS14;

−

6 to 15 for VS15,

(D) for a system having a CCT in the range of between about 7500 K and about 20000 K, the delta chroma values are as follows;

at least two color samples of the CQS are within the parameters

−

3 to 7 for VS1;

−

3 to 7 for VS2;

−

5 to 8 for VS3;

at least one color sample of the CQS is within the parameters

−

3 to 6 for VS4;

−

3 to 15 for VS5;

at least two color samples of the CQS are within the parameters

0 to 22 for VS6;

0 to 25 for VS7;

−

1 to 15 for VS8;

at least two color samples of the CQS are within the parameters

−

5 to 7 for VS9;

−

5 to 6 for VS10;

−

4 to 6 for VS11;

at least one color sample of the CQS is within the parameters

−

3 to 8 for VS12;

−

1 to 16 for VS13; and

at least one color sample of the CQS is within the parameters

−

3 to 24 for VS14;

−

4 to 15 for VS15;

wherein all delta chroma values are measured in the CIE LAB space.

23. The illumination system in accordance with claim 22, wherein the delta chroma values are preselected in accordance with the following:

(A) for a system having a CCT in the range of between about 2000 K and about 3000 K, the delta chroma values are as follows;

at least two color samples of the CQS are within the parameters

0 to 5 for VS1;

−

1 to 5 for VS2;

−

5 to 5 for VS3;

at least one color sample of the CQS is within the parameters

0 to 7 for VS4;

0 to 14 for VS5;

at least two color samples of the CQS are within the parameters

3 to 20 for VS6;

5 to 25 for VS7;

2 to 10 for VS8;

at least two color samples of the CQS are within the parameters

−

2.5 to 5 for VS9;

−

2.5 to 5 for VS10;

0 to 5 for VS1;

at least one color sample of the CQS is within the parameters

0 to 6 for VS12;

2 to 10 for VS13; and

at least one color sample of the CQS is within the parameters

2 to 10 for VS14;

2 to 10 for VS15;

(B) for a system having a CCT in the range of between about 3000 K and about 4500 K, the delta chroma values are as follows;

at least two color samples of the CQS are within the parameters

0 to 5 for VS1;

−

1 to 5 for VS2;

−

5 to −

5 for VS3;

at least one color sample of the CQS is within the parameters

0 to 7 for VS4;

0 to 14 for VS5;

at least two color samples of the CQS are within the parameters

3 to 20 for VS6;

5 to 25 for VS7;

2 to 11 for VS8;

at least two color samples of the CQS are within the parameters

−

2.5 to 5 for VS9;

−

2.5 to 5 for VS10;

0 to 5 for VS1;

at least one color sample of the CQS is within the parameters

0 to 6 for VS12;

2 to 10 for VS13; and

at least one color sample of the CQS is within the parameters

2 to 12 for VS14;

2 to 11 for VS15;

(C) for a system having a CCT in the range of between about 4500 K and about 7500 K, the delta chroma values are as follows;

at least two color samples of the CQS are within the parameters

0 to 5 for VS1;

−

1 to 5 for VS2;

−

3 to 5 for VS3;

at least one color sample of the CQS is within the parameters

−

1 to 5 for VS4;

0 to 10 for VS5;

at least two color samples of the CQS are within the parameters

3 to 15 for VS6;

5 to 18 for VS7;

2 to 12 for VS8;

at least two color samples of the CQS are within the parameters

−

2.5 to 5 for VS9;

−

2.5 to 5 for VS10;

−

2 to 5 for VS11;

at least one color sample of the CQS is within the parameters

0 to 6 for VS12;

2 to 10 for VS13; and

at least one color sample of the CQS is within the parameters

2 to 12 for VS14;

0 to 11 for VS15;

(D) for a system having a CCT in the range of between about 7500 K and about 20000 K, the delta chroma values are as follows;

at least two color samples of the CQS are within the parameters

0 to 5 for VS1;

−

1 to 5 for VS2;

−

2 to 7 for VS3;

at least one color sample of the CQS is within the parameters

−

1 to 4 for VS4;

0 to 10 for VS5;

at least two color samples of the CQS are within the parameters

3 to 15 for VS6;

5 to 16 for VS7;

2 to 12 for VS8;

at least two color samples of the CQS are within the parameters

0 to 5 for VS9;

−

2 to 5 for VS10;

−

3 to 5 for VS11;

at least one color sample of the CQS is within the parameters

0 to 6 for VS12;

1 to 10 for VS13; and

at least one color sample of the CQS is within the parameters

2 to 11 for VS14;

0 to 11 for VS15.

24. The illumination system of claim 22, wherein said plurality of inorganic light emitting diodes are arranged in a grid, a close packed configuration, or other regular pattern.

25. The illumination system of claim 22, further comprising a substrate for supporting said plurality of inorganic light emitting diodes.

26. The illumination system of claim 25, wherein said substrate comprises a heat dissipating element capable of dissipating heat from said system.

27. The illumination system of claim 22, wherein said system further includes leads for providing electric current to said plurality of inorganic light emitting diodes.

28. The illumination system of claim 22, said system further including at least one controller and at least one processor, wherein said at least one processor is configured to receive a signal from said controller to control intensity of one or more of said plurality of inorganic light emitting diodes.

29. The illumination system of claim 28, wherein said at least one controller is in communication with a sensor receptive to one or more of total light emission and temperature of one or more of said plurality of inorganic light emitting diodes.

30. The illumination system of claim 28, wherein said at least one processor controls electric current to one or more of said plurality of inorganic light emitting diodes.

31. The illumination system of claim 22, wherein said plurality of inorganic light emitting diodes are at least partially enclosed by a transparent or translucent envelope.

32. The illumination system of claim 22, said system further comprising an optical facility configured to perform at least one light-affecting operation upon light emitted from at least one of said plurality of inorganic light emitting diodes, said operation selected from the group consisting of mixing, scattering, attenuating, guiding, extracting, controlling, reflecting, refracting, diffracting, polarizing, and beam-shaping.

33. The illumination system of claim 32, wherein said optical facility includes a scattering element or optical diffuser to mix light.

34. The illumination system of claim 33, wherein said scattering element or optical diffuser is selected from at least one of film, particle, diffuser, prism, and mixing plate.

35. The illumination system of claim 32 wherein said optical facility includes a light guiding or shaping element selected from lens, filter, iris, and collimator.

36. The illumination system of claim 32, wherein said optical facility includes an encapsulant for at least one of said plurality of inorganic light emitting diodes, configured to scatter or diffuse light.

37. The illumination system of claim 32, wherein said optical facility includes a reflector, or a refractive or total-internal-reflective light guide.

38. The illumination system of claim 22, wherein at least one of said plurality of inorganic light emitting diodes comprises an inorganic nitride, carbide, or phosphide.

39. The illumination system of claim 22 wherein said system comprises at least one filter for modifying the combined light.

40. The illumination system of claim 22, wherein said system comprises at least one photoluminescent material selected from phosphor, quantum dot, and combinations thereof, for converting light from at least one of said plurality of inorganic light emitting diodes to a different wavelength.

41. The illumination system of claim 22, wherein said system comprises at least one organic electroluminescent element.

42. A method of manufacturing an illumination system comprising one or more solid state light-emitting elements having a total white light with a desired color appeal, the method comprising the steps of:

(a) providing said illumination system with total light having a given CCT value and given color point;

(b) measuring chroma values of the total light for a plurality of the Munsell color samples of the Color Quality System;

(c) calculating delta chroma values for each of the measured Munsell color samples of the Color Quality System; and

(d) comparing the calculated delta chroma values to a reference set of delta chroma values for each of said measured Munsell color samples.

43. The method of claim 42, wherein the method further comprises:

(e) adjusting spectral components of the illumination system to provide an illumination system with an adjusted total light at said given CCT value and given color point; and

(f) measuring chroma values of the adjusted total light for said plurality of the Munsell color samples of the Color Quality System.

44. The method of claim 42, wherein said reference set of delta chroma values are derived from the measurement of chroma values from blackbody radiation.

45. The method of claim 42, wherein step (b) comprises measuring chroma values of the total light for all fifteen Munsell color samples of the Color Quality System.

46. The method of claim 43, wherein the method further comprises more than one iteration of adjustment step (e) and measurement step (f).