LED Color History:
In 1963, Nick Holonyak, Jr. produced the first diode that emitted light. This light-emitting diode, (LED), was red. Since then the science of mixing atoms from different metals to create crystal wafers has grown to produce more metal substrates - giving us more colors. From 1963 to 1993, Yellow, Yellow-Green, Orange, Red-Orange and Amber were developed using mixtures predominantly composed of Aluminum, Indium, Gallium and Phosphide, (AlInGaP).

The first blue LED:
In 1993, Dr. Shuji Nakamura developed a Blue LED using Indium, Gallium and Nitride, (InGaN). This was a major breakthrough, because scientists knew that white light could be made possible by using Blue LEDs.

Making white light:
Since white light is a mixture of all wavelengths of light, it is not possible to create pure white LEDs, as LEDs are monochromatic light sources with peak wavelengths that measure to the specific nanometer. There are two ways white light can be created: Red, Green and Blue color mixing, or by using blue LEDs with a yellow Phosphor coating. The mixture of Red, Green and Blue LEDs to create white light is currently very expensive and has poor color rendering capabilities. The upside of the RGB color mix approach is that millions of different colors can be created simply by adjusting the intensity of each device. The entertainment and signage industries have celebrated and employed this technology since the early 90’s.

White light quality:
Since the first [Blue LED + Phosphor] white LEDs were created in 1996, chromaticity has improved from an extremely cool light to a warm white light, (8500K to 3200K), and color rendering is now measuring in the low 80s. Blue LED + Phosphor, (and variations on this theme), is the recommended approach if static white light is desired.