LED lamps with improved quality of light

• US 9,046,227 B2
• Filed: 10/30/2014
• Issued: 06/02/2015
• 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.
• Primary Examiner(s): VU, JIMMY T
• Application Number:
  US14/528,876
• Publication Number:
  US 20150049460A1
• Time in Patent Office: 215 Days
• Field of Search: 315/291, 315/307, 315/308, 315/312, 257/79, 257/98, 257/E33
• US Class Current: 1/1
• 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;

light is emitted by an interaction of electromagnetic radiation emitted from the at least one LED device and the wavelength conversion material; and

light emitted by the illumination system is characterized by a spectral power distribution (SPD) in which the fraction of the SPD in the range from about 390 nm to about 430 nm is between 2% and 25%.

2. The illumination system of claim 1, wherein the at least one 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 a 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, wherein the at least one LED is mounted in the at least one lamp.

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 the SPD is configured to provide a CRI of at least 90.

13. The illumination system of claim 1, wherein the illumination system is characterized by a short wavelength SPD discrepancy less than 0.5.

14. The illumination system of claim 1, wherein the illumination system is configured to have a color quality scale gamut metric of at least 1.05 and a CRI of at least 90.

15. The illumination system of claim 1, further comprising at least one second LED device.

16. 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 the illumination system is characterized by a spectral power distribution (SPD) in which the fraction of the SPD in the range from about 390 nm to about 430 nm is between 2% and 15%.

17. The illumination system of claim 16, wherein the at least one LED device comprises a gallium and nitride-containing substrate.

18. The illumination system of claim 16, wherein the at least one LED is configured to emit electromagnetic radiation within a short-wavelength range from about 390 nm to about 430 nm.

19. The illumination system of claim 16, 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.

20. The illumination system of claim 16, 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.

21. The illumination system of claim 16, 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, wherein the at least one LED is mounted in the at least one lamp.

22. The illumination system of claim 16, 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).

23. The illumination system of claim 16, 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.

24. The illumination system of claim 23, 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.

25. The illumination system of claim 16, 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.

26. The illumination system of claim 16, wherein the SPD is configured to have a color quality scale gamut metric Qg of at least 1.05.

27. The illumination system of claim 16, wherein the SPD is configured to provide a CRI of at least 90.

28. The illumination system of claim 16, wherein the illumination system is characterized by a short wavelength SPD discrepancy less than 0.5.

29. The illumination system of claim 16, wherein the illumination system is configured to have a color quality scale gamut metric of at least 1.05 and a CRI of at least 90.

30. The illumination system of claim 16, further comprising at least one second LED device.