Liquid lenses flex to adjust focus on the fly
Engineers funded by the National Institute of Biomedical Imaging and Bioengineering (NIBIB) have developed glasses with liquid-based lenses that “flex” to refocus on whatever the wearer is viewing.
“The glasses incorporate an impressive array of electrical, mechanical, optical, sensor, and computer technologies with the goal of developing a one-size-fits-all approach to vision correction,” said Andrew Weitz, Ph.D., NIBIB program director, whose expertise includes bioelectronic vision technologies.
Standard glasses compensate for the bend our ageing eyes can no longer achieve to focus. This becomes more complicated if we are unable to focus at multiple distances, which necessitates glasses with multiple lenses for different distances, such as bifocals, trifocals or progressive lenses, which must be regularly replaced as our eyesight changes.
The combination of the user’s prescription information and the distance information is used by the algorithm to instantly adjust the shape of the liquid lenses to allow the user to focus on what they are viewing. Remarkably, if the user looks elsewhere, the change in lens shape needed to focus at the new distance is made in a staggering 14 milliseconds—25 times faster than an eye blink.
“Theoretically, these would be the only glasses a person would ever have to buy because they can correct the majority of focusing problems,” says Mastrangelo. “Users just have to input their new prescription as their eyesight changes.”
Because they house a lot of technology, including a rechargeable battery, the current prototype is on the bulky side. However, the research team is constantly improving the design to make them smaller and lighter. A startup company, Sharpeyes, has been created to move toward commercialization with the aim of making the glasses available on the market in about three years.
This work was supported by the National Institute of Biomedical Imaging and Bioengineering through grant # U01EB023048.