US Patent No. 9,839,091

SYSTEMS FOR PROVIDING TUNABLE WHITE LIGHT WITH HIGH COLOR RENDERING


Patent No. 9,839,091
Issue Date December 05, 2017
Title Systems For Providing Tunable White Light With High Color Rendering
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. 9,839,091

1. A semiconductor light emitting device, comprising:
a solid state emitter package comprising:
a first solid state emitter that excites a first luminescent material;
a second solid state emitter that excites a second luminescent material;
a third solid state emitter that excites a third luminescent material; and
a fourth solid state emitter that excites a fourth luminescent material; and
a control circuit configured to independently apply an on-state drive current to each of the first, second, third, and fourth
solid state emitters;

wherein the first solid state emitter and the first luminescent material together emit a first unsaturated light having a
first color point within a blue color range defined by a line connecting the ccx, ccy color coordinates of the infinity point
of the Planckian locus (0.242, 0.24) and (0.12, 0.068), the Planckian locus from 4000K and infinite CCT, the constant CCT
line of 4000K, the line of purples, and the spectral locus;

wherein the second solid state emitter and the second luminescent material together emit a second unsaturated light having
a second color point within a red color range defined by the spectral locus between the constant CCT line of 1600K and the
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 solid state emitter and the third luminescent material together emit a third unsaturated light having a
third color point within a yellow/green color range 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);

wherein the fourth solid state emitter and the fourth luminescent material together emit a fourth unsaturated light having
a fourth color point within a cyan color range defined by a line connecting the ccx, ccy color coordinates (0.18, 0.55) and
(0.27, 0.72), the constant CCT line of 9000K, the Planckian locus between 9000K and 4600K, the constant CCT line of 4600K,
and the spectral locus; and

wherein the control circuit is configured to adjust a fifth color point of a fifth unsaturated light that results from a combination
of the first, second, third, and fourth unsaturated light.