Objects can now change colors like a chameleon

The color-changing capabilities of chameleons have long bewildered willing observers. The philosopher Aristotle himself was long mystified by these adaptive creatures. But while humans can't yet camouflage much beyond a green outfit to match grass, inanimate objects are another story. A team from MIT's Computer Science and Artificial Intelligence Laboratory (CSAIL) has brought us closer to this chameleon reality, by way of a new system that uses reprogrammable ink to let objects change colors when exposed to ultraviolet (UV) and visible light sources. Dubbed "PhotoChromeleon," the system uses a mix of photochromic dyes that can be sprayed or painted onto the surface of any object to change its color -- a fully reversible process that can be repeated infinitely.