How do these glasses automatically adjust their focus?

Progressive lenses on eyewear could soon be a thing of the past. IXI, a startup based in Finland, has developed glasses that can automatically adjust the focus of the lens based on what you’re looking at. While they may not be the first to the idea, the result is probably the most fashionable option yet.

IXI’s glasses look just like a regular pair of spectacles, and they weigh about the same too at 22 grams. Their innovation is in the lenses — a layer of liquid crystals between the optical elements of the lenses. Liquid crystals are common in gadgets with screens like smartphones and LCD TVs, and they are particularly useful in this case due to their low energy use.

Sensors in the frames track the wearer’s eye movement to determine when you are looking at a nearby object. Then the frames apply a small voltage to liquid crystals in the lenses, causing them to rearrange in a way that alters the focus. When the wearer’s eyes return to looking at something further away, this “near-focus” mode deactivates and the lenses return to their normal state for distance viewing. The glasses only have small onboard batteries for this, so they need to be charged daily. IXI has yet to release details on a launch date or pricing.