Systems For Providing Tunable White Light with High Color Rendering

Abstract

The present disclosure provides systems for generating tunable white light. The systems include a plurality of LED strings that generate light with color points that fall within blue, yellow/green, red, and cyan color ranges, with each LED string being driven with a separately controllable drive current in order to tune the generated light output.

What is claimed is: 
     
         1 . A method of forming a light emitting apparatus, the method comprising:
 providing a substrate,   mounting a first LED, a second LED, a third LED, and a fourth LED on the substrate,   providing first, second, third, and fourth luminophoric mediums in illuminative communication with the first, second, third, and fourth LEDs, respectively, and   adjusting the relative values of unsaturated light emitted from the first, second, third, and fourth LEDs and the first, second, third, and fourth luminophoric mediums 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,   wherein the first LED and first luminophoric medium together emit a first unsaturated light having a first spectral power distribution having spectral power distribution intensity of between 3.3 and 17.4 for the wavelength range of 380 nm to 500 nm, between 8.9 and 24.8 for the wavelength range of 501 nm to 600 nm, and between 1.1 and 18.1 for the wavelength range of 701 nm to 780 nm, relative to a value of 100.0 for the wavelength range of 601 nm to 700 nm.   
     
     
         2 - 24 . (canceled)