By age 45, most of us will need glasses at least for reading. That’s because our eyes’ ability to accommodate—to change focus to see objects at different distances—degrades with age. In young eyes, the eyeball’s crystalline lens changes shape easily, allowing this accommodation. But as we get older, this lens stiffens. Objects in close range suddenly look blurry. Hence the “readers” most middle-aged adults begin wearing on a chain or tucking in a handbag, or the bifocals worn by those who already had vision problems.
But the days of popping reading glasses on and off or constantly shifting your gaze through bifocals may be numbered. Researchers at the University of Utah have developed “smart glasses” with liquid lenses that can automatically adjust their focus.
Regular prescription glasses, Mastrangelo explains, don’t fix the eyes’ accommodation problems. They simply shift the range of what’s in focus rather than expanding it. So if you put on a pair of reading glasses, the once-blurry page a foot from your eyes will be clear, but objects on the other side of the room will suddenly be blurry. The reverse is true of people who need glasses only for seeing far distances.
Though the glasses have not yet been formally tested, Mastrangelo and other members of his lab have tried them out. The current prototype is, to put it gently, bulky (think a clear version of Doc’s goggles in Back to the Future). Formal wearer tests are in the works.
Some adjustments will need to be made before the glasses could be ready for the market, Mastrangelo says. They need to reduce the weight and thickness of the eyepieces and make the electronic subsystems smaller. They also need “much improved” styling. Mastrangelo expects to overcome these issues and have a product on shelves within two to three years.
