Research (time and resource limited)
This is an entire object or entire surface coating, not segmented like pixels. Color will be changeable at will.
The coating will consist of 7 layers on the surface of said object. This could possibly be done with 5 coatings and a base coat of paint that doesn't change. The top, bottom, and 2 intermediate layers will be electrically conductive, but all will be transparent. The dyes (either RGB or RYB) will be in the other three layers, one color to a layer.
The dyes will be electrically charged, so that voltage across any two of the adjacent conductive layers will cause a color change in the intermediate layer. I was thinking one polarity to make the color show and the reverse to make it disappear with varying voltage related to varying color intensity. Once the color is set, voltage no longer need be applied. Color change circuitry would be built into the object.
Theoretically, any composite color could be created given that you can choose any voltage value across the conductive layers. The time required for a change would be acceptable at anywhere from 1 second to 1 hour.
Applications (restricted to smooth surfaces only)
- Vehicles - Transition times of less than 10 seconds on vehicles would most likely be outlawed due to the ability to confuse the crap out of cops.
- Child toys
- lots more
Electrodyes as I call them are more commonly known as electrochromic polymers. People have apparently been looking into this type of technology for quite a while. It seems that what I describe here is almost exactly how these coatings are being created. The dyes themselves are transparent when in their natural state, but change color when oxidized. This is the one crucial piece of information that I had not come up with so far. Commonly used polymers are poly(3,4-ethylenedioxythiophene) (PEDOT), poly(1-methyl pyyrole) (PN-MeP), polyaniline (PAni), and poly(bis[2-(5,2'-dithienyl)]dimethylsilane) (PBTDMS). The viologen class of materials also serve as a good electrochromic polymer.