Methods of producing melanopic emission spectra with high visual quality

Abstract

A light emitting diode (LED) with a melanopic emission spectrum can comprise a primary light source and a phosphor. The primary light source can comprise an emission spectrum comprising a first peak centered at a wavelength from 480 nm to 500 nm. The phosphor, when excited, can comprise an emission spectrum with a second peak centered at a wavelength from 640 nm to 750 nm, and the intensity of the first peak is greater than the intensity of the second peak. A light emitting apparatus can comprise a first LED with a traditional white light emission spectrum, and a second LED with a melanopic emission spectrum. The light emitted from the apparatus can comprise chromaticity coordinates, in the CIE 1931 color space diagram using the 1964 10° Supplementary Standard Observer, that are within a one-step MacAdam ellipse from the black body locus with chromaticity coordinate x from 0.34 to 0.45.

What is claimed is: 
     
         1 . A method, comprising:
 providing a first light emitting diode (LED) with an emission spectrum comprising a first color on the International Commission on Illumination (CIE) 1931 color space diagram within the American National Standards Institute (ANSI) 3500 K Bin; and   providing a second LED with a melanopic emission spectrum comprising:
 a second color on the CIE 1931 Color Space diagram that is below the black body locus using the CIE 1931 2-degree observer and above the black body locus using the CIE 1967 10-degree observer; 
 a first peak emitted from a primary light source of the second LED centered at a wavelength from 480 nm to 500 nm; 
 a second peak emitted from a phosphor of the second LED centered at a wavelength from 640 nm to 750 nm; and 
 a first maximum power density in a wavelength range from 480 nm to 500 nm greater than a second maximum power density in a wavelength range from 400 nm to 480 nm; and 
   combining light from the first and second LEDs in a human circadian regulation lighting system with an intensity ratio such that a spectrum of combined light from the first and the second LEDs comprises:
 a third maximum power density in a wavelength range from 480 nm to 500 nm greater than a fourth maximum power density in a wavelength range from 400 nm to 480 nm; and 
 a third color on the CIE 1931 Color space diagram inside of the ANSI 4000 K Bin using the CIE 1967 10-degree observer. 
   
     
     
         2 . The method of  claim 1 , wherein the first maximum power density in the wavelength range from 480 nm to 500 nm of the melanopic emission spectrum of the second light emitting diode (LED) is at least 80% of a fifth maximum power density in the wavelength range from 500 nm to 700 nm of the melanopic emission spectrum of the second light emitting diode (LED). 
     
     
         3 . The method of  claim 1 , wherein the melanopic emission spectrum of the second light emitting diode (LED) further comprises a first intensity of the first peak that is greater than a second intensity of the second peak. 
     
     
         4 . The method of  claim 1 , wherein the primary light source of the second light emitting diode (LED) comprises InGaN and the first peak is centered at a wavelength of 490 nm. 
     
     
         5 . The method of  claim 1 , wherein the phosphor of the second light emitting diode (LED) comprises CaAlSiN 3 :Eu 2   + . 
     
     
         6 . The method of  claim 1 , wherein chromaticity coordinates (x,y) of the melanopic emission spectrum of the second light emitting diode (LED), in the International Commission on Illumination (CIE) 1931 color space diagram, shift in a negative x direction and a positive y direction from chromaticity coordinates using the 1931 2° Standard Observer to chromaticity coordinates using the 1964 10° Supplementary Standard Observer. 
     
     
         7 . The method of  claim 1 , wherein the combined light from the first and second light emitting diodes (LEDs) has a color rendering index (CRI) greater than 80. 
     
     
         8 . A method, comprising:
 providing a first light emitting diode (LED) with an emission spectrum comprising a first color on the International Commission on Illumination (CIE) 1931 color space diagram within the American National Standards Institute (ANSI) 3000 K Bin; and   providing a second LED with a melanopic emission spectrum comprising:
 a second color on the CIE 1931 Color Space diagram that is below the black body locus using the CIE 1931 2-degree observer and above the black body locus using the CIE 1967 10-degree observer; 
 a first peak emitted from a primary light source of the second LED centered at a wavelength from 480 nm to 500 nm; 
 a second peak emitted from a phosphor of the second LED centered at a wavelength from 640 nm to 750 nm; and 
 a first maximum power density in a wavelength range from 480 nm to 500 nm greater than a second maximum power density in a wavelength range from 400 nm to 480 nm; and 
   combining light from the first and second LEDs in a human circadian regulation lighting system with an intensity ratio such that a spectrum of combined light from the first and the second LEDs comprises:
 a third maximum power density in a wavelength range from 480 nm to 500 nm greater than a fourth maximum power density in a wavelength range from 400 nm to 480 nm; and 
 a third color on the CIE 1931 Color space diagram inside of the ANSI 3500 K Bin using the CIE 1967 10-degree observer. 
   
     
     
         9 . The method of  claim 8 , wherein the first maximum power density in the wavelength range from 480 nm to 500 nm of the melanopic emission spectrum of the second light emitting diode (LED) is at least 80% of a fifth maximum power density in the wavelength range from 500 nm to 700 nm of the melanopic emission spectrum of the second light emitting diode (LED). 
     
     
         10 . The method of  claim 8 , wherein the melanopic emission spectrum of the second light emitting diode (LED) further comprises a first intensity of the first peak that is greater than a second intensity of the second peak. 
     
     
         11 . The method of  claim 8 , wherein the primary light source of the second light emitting diode (LED) comprises InGaN and the first peak is centered at a wavelength of 490 nm. 
     
     
         12 . The method of  claim 8 , wherein the phosphor of the second light emitting diode (LED) comprises CaAlSiN 3 :Eu 2   + . 
     
     
         13 . The method of  claim 8 , wherein chromaticity coordinates (x,y) of the melanopic emission spectrum of the second light emitting diode (LED), in the International Commission on Illumination (CIE) 1931 color space diagram, shift in a negative x direction and a positive y direction from chromaticity coordinates using the 1931 2° Standard Observer to chromaticity coordinates using the 1964 10° Supplementary Standard Observer. 
     
     
         14 . A method, comprising:
 providing a first light emitting diode (LED) with an emission spectrum comprising a first color on the International Commission on Illumination (CIE) 1931 color space diagram within the American National Standards Institute (ANSI) 2700 K Bin; and   providing a second LED with a melanopic emission spectrum comprising:
 a second color on the CIE 1931 Color Space diagram that is below the black body locus using the CIE 1931 2-degree observer and above the black body locus using the CIE 1967 10-degree observer; 
 a first peak emitted from a primary light source of the second LED centered at a wavelength from 480 nm to 500 nm; 
 a second peak emitted from a phosphor of the second LED centered at a wavelength from 640 nm to 750 nm; and 
 a first maximum power density in a wavelength range from 480 nm to 500 nm greater than a second maximum power density in a wavelength range from 400 nm to 480 nm; and 
   combining light from the first and second LEDs in a human circadian regulation lighting system with an intensity ratio such that a spectrum of combined light from the first and the second LEDs comprises:
 a third maximum power density in a wavelength range from 480 nm to 500 nm greater than a fourth maximum power density in a wavelength range from 400 nm to 480 nm; and 
 a third color on the CIE 1931 Color space diagram inside of the ANSI 3000 K Bin using the CIE 1967 10-degree observer. 
   
     
     
         15 . The method of  claim 14 , wherein the first maximum power density in the wavelength range from 480 nm to 500 nm of the melanopic emission spectrum of the second light emitting diode (LED) is at least 80% of a fifth maximum power density in the wavelength range from 500 nm to 700 nm of the melanopic emission spectrum of the second light emitting diode (LED). 
     
     
         16 . The method of  claim 14 , wherein the melanopic emission spectrum of the second light emitting diode (LED) further comprises a first intensity of the first peak that is greater than a second intensity of the second peak. 
     
     
         17 . The method of  claim 14 , wherein the primary light source of the second light emitting diode (LED) comprises InGaN and the first peak is centered at a wavelength of 490 nm. 
     
     
         18 . The method of  claim 14 , wherein the phosphor of the second light emitting diode (LED) comprises CaAlSiN 3 :Eu 2   + . 
     
     
         19 . The method of  claim 14 , wherein chromaticity coordinates (x,y) of the melanopic emission spectrum of the second light emitting diode (LED), in the International Commission on Illumination (CIE) 1931 color space diagram, shift in a negative x direction and a positive y direction from chromaticity coordinates using the 1931 2° Standard Observer to chromaticity coordinates using the 1964 10° Supplementary Standard Observer.