Combining regular lens technology with nanoparticles, researchers have created prototypes of contact lenses that allow people to see in the dark — and through their eyelids.

A team in China has woven tiny, light-converting particles into soft contact lenses, granting wearers the power to perceive infrared light both in the dark and, surprisingly, with their eyes closed. The “seeing with your eyes shut” part arises because near-infrared light penetrates the eyelid more effectively than visible light.