US Patent No. 10,512,133

METHODS OF PROVIDING TUNABLE WARM WHITE LIGHT


Patent No. 10,512,133
Issue Date December 17, 2019
Title Methods Of Providing Tunable Warm White Light
Inventorship Raghuram L. V Petluri, Los Angeles, CA (US)
Paul Kenneth Pickard, Los Angeles, CA (US)
Assignee Ecosense Lighting Inc., Los Angeles, CA (US)

Claim of US Patent No. 10,512,133

1. A method of generating white light, the method comprising:producing light from a first light emitting diode (“LED”) string that comprises a blue LED with a peak wavelength of between about 405 nm and about 470 nm;
producing light from a second light emitting diode (“LED”) string that comprises a blue LED with a peak wavelength of between about 405 nm and about 470 nm;
producing light from a third light emitting diode (“LED”) string that comprises a blue LED with a peak wavelength of between about 405 nm and about 470 nm;
passing the light produced by each of the first, second, and third LED strings through one of a plurality of respective luminophoric mediums to produce a first unsaturated light, a second unsaturated light, and a third unsaturated light, respectively; and
combining the first unsaturated light, the second unsaturated light, and the third unsaturated light together into a fourth unsaturated light;
wherein the first unsaturated light has a first color point within a white color range defined by a polygonal region on the 1931 CIE Chromaticity Diagram defined by the following ccx, ccy color coordinates: (0.4006, 0.4044), (0.3736, 0.3874), (0.3670, 0.3578), (0.3898, 0.3716);
wherein the second unsaturated light has a second color point within a red color range on the 1931 CIE Chromaticity Diagram defined by a spectral locus between the constant CCT line of 1600K and a line of purples, the line of purples, a line connecting the ccx, ccy color coordinates (0.61, 0.21) and (0.47, 0.28), and the constant CCT line of 1600K;
wherein the third unsaturated light has a third color point within a yellow/green color range on the 1931 CIE Chromaticity Diagram defined by the constant CCT line of 4600K, the Planckian locus between 4600K and 550K, the spectral locus, and a line connecting the ccx, ccy color coordinates (0.445, 0.555) and (0.38, 0.505); and
wherein the fourth unsaturated light corresponds to at least one of a plurality of points along a predefined path near a black body locus in the 1931 CIE Chromaticity Diagram within a 7-step MacAdam ellipse around any point on the black body locus having a correlated color temperature between about 1800K and about 3200K;
wherein the second unsaturated light has a spectral power distribution having relative spectral power intensities of between 0% and 14.8% for wavelengths between 380-420 nm, between 2.1% and 157.8% for wavelengths between 421-460 nm, between 2.0% and 6.7% for wavelengths between 461-500 nm, between 1.4% and 12.2% for wavelengths between 501-540 nm, between 8.7% and 24.7% for wavelengths between 541-580 nm, between 48.5% and 102.8% for wavelengths between 581-620 nm, between 1.8% and 74.3% for wavelengths between 661-700 nm, between 0.5% and 29.5% for wavelengths between 701-740 nm, and between 0.3% and 9% for wavelengths between 741-780 nm, relative to the normalized range for wavelengths between 621-660 nm with a value of 100.0%.