Our vision changes with age. Even if we have perfect vision in our youth and young adulthood, by 45 the aging process typically starts to gradually degrade our eyes’ ability to focus accurately. The degradation is a gradual process which means there are two variables when we want to see something clearly: the object’s distance from the eye lenses and our age. Once diagnosed with poor vision, many people require a new prescription — and thus new glasses — every 18 to 24 months. As someone who started wearing bifocals at age 12, I have had plenty of experience with various types of multi-focus lenses: bifocals, progressive lenses, and now multifocal intraocular lenses (IOLs) following cataract surgery. Over the course of 58 years, that’s a lot of different prescriptions for glasses, contact lenses, and now lens implants.
But what if we could have one pair of glasses that lasted our entire lives? Scientists at the University of Utah‘s Utah Science Technology and Research (USTAR) economic development initiative have developed smart glasses that adjust the focus of lenses made of glycerin enclosed by flexible rubber-like membranes. A distance meter in the middle of glasses’ frame judges the distance to the object of interest and three mechanical actuators adjust the curvature of the liquid lens so you can see clearly. The glasses’ frame holds the 24-hour rechargeable battery to power the autofocusing system based on distance and a vision corrective prescription stored in nonvolatile memory. A Bluetooth connection with a smartphone enables prescription changes so theoretically you’d never need new glasses.
More detail on the Utah team’s autofocusing glasses is available in a paper published by OSA The Optical Society. The current prototype’s frames are a bulky anti-fashion statement, but style aside, the future potential is wonderful for a single set of glasses that can last a lifetime, barring other human lens or other optic issues such as cataracts, glaucoma, or macular degeneration.