LED LAMPS WITH IMPROVED QUALITY OF LIGHT

• US 20140301062A1
• Filed: 06/20/2014
• Published: 10/09/2014
• Est. Priority Date: 09/18/2009
• Status: Active Grant

• Current Assignee: Korrus Incorporated (MKD Electric, Inc.)
• Original Assignee: Soraa, Inc.
• Inventors: David, Aurelien J.F., Trottier, Troy A., Krames, Michael R.
• Granted Patent: US 8,933,644 B2
• Time in Patent Office: Days
• US Class Current: 362/84
• CPC Class Codes: F21K 9/23 Retrofit light sources for lighting devices with a single fitting for each light source, e.g. for substitution of incandescent lamps with bayonet or threaded fittings
• 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 9/233 specially adapted for generating a spot light distribution, e.g. for substitution of reflector lamps
• CPC Class Codes: F21K 9/62 using mixing chambers, e.g. housings with reflective walls
• 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: F21V 13/08 the elements being filters or photoluminescent elements and reflectors
• CPC Class Codes: F21V 13/14 the elements being filters or photoluminescent elements, reflectors and refractors
• CPC Class Codes: F21V 23/02 the elements being transformers, impedances or power supply units, e.g. a transformer with a rectifier
• CPC Class Codes: F21V 23/04 the elements being switches safety devices F21V25/00
• CPC Class Codes: F21V 29/70 characterised by passive heat-dissipating elements, e.g. heat-sinks
• CPC Class Codes: F21V 3/00 Globes; Bowls; Cover glasses with refracting properties F21V5/00; with reflecting properties F21V7/00; characterised by cooling arrangements F21V29/506
• CPC Class Codes: F21V 7/04 Optical design
• CPC Class Codes: F21V 9/38 Combination of two or more photoluminescent elements of different materials
• CPC Class Codes: F21Y 2113/13 comprising an assembly of point-like light sources
• 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 27/153 in a repetitive configuration, e.g. LED bars
• 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 33/20 with a particular shape, e.g. curved or truncated substrate
• CPC Class Codes: H01L 33/32 : containing nitrogen
• CPC Class Codes: H01L 33/483 : Containers
• CPC Class Codes: H01L 33/502 : Wavelength conversion materials
• CPC Class Codes: H01L 33/504 : Elements with two or more wavelength conversion materials
• CPC Class Codes: H01L 33/505 : characterised by the shape, e.g. plate or foil
• CPC Class Codes: H01L 33/60 : Reflective elements

Abstract

LED lamp systems having improved light quality are disclosed. The lamps emit more than 500 lm and more than 2% of the power in the spectral power distribution is emitted within a wavelength range from about 390 nm to about 430 nm.

Claims

1. An illumination system comprising:

at least one LED device configured in a housing structure, wherein the at least one LED device comprises an n-type region, a light-emitting active region, and a p-type region;

a wavelength conversion material optically coupled to the at least one LED device; and

a power source electrically coupled to the at least one LED device;

wherein,

the at least one LED device is characterized by an external quantum efficiency greater than 45% measured at an ambient temperature of 25°

C. and at a current density of 40 A/cm²; and

light emitted by an interaction of electromagnetic radiation emitted from the at least one LED device and from the wavelength conversion material is characterized by a spectral power distribution (SPD) in which from 1% to 4% of the power in the SPD is emitted within a short-wavelength range from about 390 nm to about 430 nm.

2. The illumination system of claim 1, wherein the LED device comprises a gallium and nitride-containing substrate.

3. The illumination system of claim 1, wherein the at least one LED is configured to emit electromagnetic radiation within the short-wavelength range from about 390 nm to about 430 nm.

4. The illumination system of claim 1, wherein,

the wavelength conversion material comprises a blue phosphor and a green phosphor;

and

the green phosphor is configured to absorb electromagnetic radiation emitted by the blue phosphor.

5. The illumination system of claim 1, comprising a second LED device, wherein the second LED device is configured to emit electromagnetic radiation within a blue wavelength range, within a green wavelength range, or within a red wavelength range.

6. The illumination system of claim 1, comprising one or more luminaires and at least one lamp selected from a MR16 lamp, a PAR30 lamp, a AR111 lamp, an A-lamp, and a combination of any of the foregoing.

7. The illumination system of claim 1, wherein,

the SPD is configured to render a color or a white object comprising an optical brightening agent (OBA) to be substantially equal to a color of the white object under illumination by a reference illuminant;

and

the SPD and the reference illuminant are characterized by the same correlated color temperature (CCT).

8. The illumination system of claim 1, wherein,

the SPD is configured to render a color of a white object comprising an OBA to provide a first color difference and a second color difference;

the first color difference is the difference between a chromaticity of the object under illumination by the SPD and a chromaticity of the SPD;

the second color difference is the difference between a chromaticity of the object under illumination by a reference illuminant characterized by a CCT as the SPD, and a chromaticity of the reference illuminant;

the SPD and the reference illuminant are characterized by substantially the same CCT; and

the first color difference and the second color difference are within a predetermined range and are substantially equal in direction and magnitude in color space.

9. The illumination system of claim 8, wherein,

the white object is a high whiteness reference object;

each of the first color difference and the second color differences is a Du′

v′

color difference; and

the predetermined range is ±

3 Du′

v′

points.

10. The illumination system of claim 1, wherein the SPD is characterized by a correlated color temperature in the range from 2000K to 10000K and by a color rendering index of at least 90.

11. The illumination system of claim 1, wherein the SPD is configured to have a color quality scale gamut metric Qg of at least 1.05.

12. The illumination system of claim 1, wherein from 2% to 4% of the power in the SPD is emitted within a short-wavelength range from about 390 nm to about 430 nm.

13. The illumination system of claim 1, wherein the wavelength conversion material is configured to provide a CRI of at least 90.

14. The illumination system of claim 1, wherein the illumination system is characterized by a SPD violet fraction less than 25% and a short wavelength SPD discrepancy less than 0.5.

15. An illumination system comprising:

at least one LED device configured in a housing structure, wherein the at least one LED device comprises an n-type region, a light-emitting active region, and a p-type region;

a wavelength conversion material optically coupled to the at least one LED device; and

a power source electrically coupled to the at least one LED device;

wherein,

light emitted by the at least one LED is characterized by a spectral power distribution (SPD) configured to render a white object comprising an OBA to provide a first color difference and a second color difference;

the first color difference is the difference between a chromaticity of the object under illumination by the SPD and the chromaticity of the SPD;

the second color is the difference between a chromaticity under illumination by a reference illuminant and a chromaticity of the reference illuminant;

the SPD and the reference illuminant are characterized by substantially the same CCT; and

the first color difference and the second color difference are within a predetermined range and are substantially equal in direction and magnitude in color space.

16. The illumination system of claim 15, wherein,

the white object is a high whiteness reference object;

each of the first color difference and the second color difference is a Du′

v′

color difference; and

the predetermined range is ±

3 Du′

v′

points.

17. The illumination system of claim 15, wherein,

the white object is a high whiteness reference object;

each of the first color difference and the second color difference is a CCT-Corrected Whiteness difference; and

the predetermined range is ±

15 whiteness points.

18. The illumination system of claim 15,

wherein the at least one LED is configured to emit electromagnetic radiation within the short-wavelength range from about 390 nm to about 430 nm;

and

the illumination system comprises a second LED device, wherein the second LED device is configured to emit electromagnetic radiation within a blue wavelength range, within a green wavelength range, or within a red wavelength range.

19. The illumination system of claim 15, wherein from 1% to 4% of the power in the SPD is emitted within a short-wavelength range from about 390 nm to about 430 nm.

20. The illumination system of claim 15, wherein the wavelength conversion material is configured to provide a CRI of at least 90.

21. The illumination system of claim 15, wherein the illumination system is characterized by a SPD violet fraction less than 25% and a short wavelength SPD discrepancy less than 0.5.

22. An illumination system comprising:

at least one LED device configured in a housing structure, wherein the at least one LED device comprises an n-type region, a light-emitting active region, and a p-type region;

a wavelength conversion material optically coupled to the at least one LED device; and

a power source electrically coupled to the at least one LED device;

wherein

the at least one LED device is characterized by an external quantum efficiency greater than 45% measured at an ambient temperature of 25°

C. and at a current density of 40 A/cm²;

a light emitted by an interaction of electromagnetic radiation emitted from the at least one LED device and from the wavelength conversion material is characterized by a spectral power distribution (SPD) having a short-wavelength spectra discrepancy (SWSD) less than 0.5.

23. The illumination system of claim 22 wherein,

the SPD is configured to render a color of a white object comprising an OBA to be substantially equal to a color of the white object under illumination by a reference illuminant;

and

the SPD and the reference illuminant are characterized by substantially the same CCT.

24. The illumination system of claim 22, wherein,

the SPD is configured to render a white object containing an OBA to provide a first color difference and a second color difference;

the first color difference is the difference between a chromaticity of the object under illumination by the SPD and a chromaticity of the SPD;

the second color difference is the difference between a chromaticity of the object under illumination by a reference illuminant and a chromaticity of the illuminant;

the SPD and the CCT are characterized by substantially the same CCT; and

the first color difference and the second color difference are within a predetermined range and are substantially equal in direction and magnitude.

25. The illumination system of claim 24, wherein,

the white object is a high whiteness reference object;

each of the first color difference and the second color differences is a Du′

v′

color difference; and

the predetermined range is ±

3 Du′

v′

points.

27. The illumination system of claim 22, wherein from 2% to 4% of the power in the SPD is emitted within a short-wavelength range from about 390 nm to about 430 nm.

28. The illumination system of claim 22, wherein the wavelength conversion material is configured to provide a CRI of at least 90.

29. The illumination system of claim 22, wherein the illumination system is characterized by a SPD violet fraction less than 25% and a short wavelength SPD discrepancy less than 0.5.

30. An illumination system comprising:

at least one LED device configured in a housing structure, wherein the at least one LED device comprises an n-type region, a light-emitting active region, and a p-type region;

a wavelength conversion material optically coupled to the at least one LED device; and

a power source electrically coupled to the at least one LED device;

wherein

the at least one LED device is characterized by an external quantum efficiency greater than 45% measured at an ambient temperature of 25°

C. and at a current density of 40 A/cm²;

the wavelength conversion material is configured such that from 2% to 4% of the power in the SPD is emitted within a short-wavelength range from about 390 nm to about 430 nm;

the wavelength conversion material is configured to provide a CRI of at least 90; and

the illumination system is characterized by a SPD violet fraction less than 25% and a short wavelength SPD discrepancy less than 0.5.