The biomimetic lens are made of stretchy polymer films that respond to the electric signals generated by your eyes when they make a movement, such as blinking. Known as electrooculographic signals, humans are even capable of emitting the electric impulses when they’re sleeping. “Even if your eye cannot see anything, many people can still move their eyeball and generate this electro-oculographic signal,” said lead researcher Shengqiang Cai to New Scientist.