PopSci:

"Babak Parviz and his team made a lens that displays a single pixel that can be turned on and off wirelessly. An integrated circuit stores the energy, and a light-emitting diode shoots light toward the eye, but the optics are tricky. You can’t focus on something that’s that close. To correct this, they put a series of tiny lenses between the LED and the eye—imagine holding your finger too close to your eye so it’s blurry; you could bring it into focus by putting a magnifying glass between your eye and your finger." (Gadgets, Hi-tech)