The ability of many cephalopods (cuttlefish, squid and octopus) to change their surface color and texture has long fascinated engineers. "It's a fantastic quality, and one unprecedented in human engineering," lead author and MIT mechanical engineering professor Xuanhe Zhao says.
Zhao's material mimics the ability of a cephalopod to flex its muscles, exposing different spots of pigment to make them more or less prominent. In doing this, they also change their texture from smooth to bumpy. The new material uses a stretchy polymer that reacts to an external electric voltage. As electricity switches it on and off, it changes from a smooth, nearly colorless surface to a bumpy, dark blue, fluorescent one. For now, the color and texture change go hand in hand. But by adding multiple layers of the polymer, Zhao says, they might be able to control color and texture independently.
Because the material used is so stretchy, the display is quite flexible. Flexible displays could be used for wearable computing devices and more durable electronics, but Zhao has high hopes for his display's use in military camouflage.
"The military spends millions of dollars developing new camouflage patterns, but they're all static right now...they don't change," Zhao says. "If you put a pattern designed for the forest into the desert, it's not going to function as camouflage, and it might even make you more conspicuous than no camouflage at all."
Dynamic camouflage would allow soldiers and military vehicles to adapt to their surroundings instantly. Zhao's display is in its early stages, but one thing is almost certain: If scientists develop quick-changing camouflage materials, we'll have cephalopods to thank.