A new paper published in the journal Optics Express unveiled research to create ‘smart glasses’ that use liquid lenses to adjust their focus, potentially replacing bifocals and the need for reading glasses. The research was led by Carlos Mastrangelo, an electrical engineering professor at the University of Utah, and doctoral student Nazmul Hasan, published in a special edition of the journal last week.
“Most people who get reading glasses have to put them on and take them off all the time. You don’t have to do that anymore. You put these on, and it’s always clear,” said Mastrangelo.
As people age, their eyes often lose the ability to adjust focal depth based on the distance of what they are looking at. This can result in nearsightedness or farsightedness, and the need for reading glasses or bifocals to see close objects, and regular eyeglasses to see more distant objects.
The researchers developed a lense made from glycerin, a colorless liquid. Enclosed by flexible membranes in the front and back.
“The focal length of the glasses depends on the shape of the lens, so to change the optical power we actually have to change the membrane shape,” Mastrangelo said.
The lenses are placed in special powered frames designed by the researchers, that a batter to power the actuators. A distance meter is built into the bridge of the frames that uses pulses of infrared light to measure the distance to an object and controls the actuators which curve the lenses. If the wearer then sets their signs on a closer object, the distance reader tells the actuators to reshape the lenses to address farsightedness. According to Hasan, the lenses can change focus from one object to another in just 14 seconds.
The frames uses a rechargeable battery that can hold 24 hours worth of charge.
Before wearing the glasses for the first time, users will be able to input their eyeglass prescription into a smartphone app that is connected to the glasses. The app will calibrate the lenses using a Bluetooth connection. Users will only need to go through that process once, unless their prescription changes over time. In theory, the wearer could never need to purchase new eyeglasses again, with these automatically adjusting to any changes in their eyesight.
So far, the researchers have constructed only a rudimentary prototype, which was unveiled at the Consumer Electronics Show in Las Vegas last month. However, smaller and lighter designs are expected to replace the bulky prototype. The researchers created a startup company for the classes, called Sharpeyes LLC – expected to offer a new, more attractive version of the glasses in as soon as three years.