This is my idea. It would already have been developped if I were rich! It pisses me off. Fortunately, the dumb-ass designer doesn't seem to have taken it as far as I did. I would alternate Red, Green, and Blue LEDS to create any color you want.
I also invented the self-vacuuming robot a decade ago.
I need a team of scientists at my disposal.
http://www.livescience.com/technology/051214_electronic_walls.html