Engineers develop 'smart glasses' that automatically focus on what wearer sees

January 25, 2017, University of Utah
Early prototype of 'smart glasses' with liquid-based lenses that can automatically adjust the focus on what a person is seeing, whether it is far away or close up. The lenses are placed in battery-powered frames that can automatically adjust the focal length of the lenses based on what the wearer is looking at. Researchers expect to have smaller, lighter frames with the technology in as early as three years. Credit: Dan Hixson/University of Utah College of Engineering

The days of wearing bifocals or constantly swapping out reading glasses might soon come to an end.

A team led by University of Utah electrical and computer engineering professor Carlos Mastrangelo and doctoral student Nazmul Hasan has created "" with liquid-based lenses that can automatically adjust the focus on what a person is seeing, whether it is far away or close up. Research on the adaptive lenses was published this week in a special edition of the journal, Optics Express. The paper was co-authored by U electrical and computer engineering associate professor Hanseup Kim and graduate researcher Aishwaryadev Banerjee.

"Most people who get have to put them on and take them off all the time," says Mastrangelo, who also is a professor for USTAR, the Utah Science Technology and Research economic development initiative. "You don't have to do that anymore. You put these on, and it's always clear."

The human eye has a lens inside that adjusts the focal depth depending on what you look at. But as people age, the lens loses its ability to change focus, which is why many people ultimately require reading glasses or bifocals to see objects up close and regular eyeglasses to see far away, also known as farsightedness and nearsightedness, respectively.

University of Utah electrical and computer engineering professor Carlos Mastrangelo, right, and doctoral student Nazmul Hasan have created 'smart glasses' with liquid-based lenses that can automatically adjust the focus on what a person is seeing, whether it is far away or close up. Credit: Dan Hixon/University of Utah College of Engineering

So Mastrangelo and Hasan have created eyeglass lenses made of glycerin, a thick colorless liquid enclosed by flexible rubber-like membranes in the front and back. The rear membrane in each lens is connected to a series of three mechanical actuators that push the membrane back and forth like a transparent piston, changing the curvature of the liquid lens and therefore the focal length between the lens and the eye.

"The 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 says.

The lenses are placed in special eyeglass frames also invented by Mastrangelo, Hasan and other members of the research group with electronics and a battery to control and power the actuators. In the bridge of the glasses is a distance meter that measures the distance from the glasses to an object via pulses of infrared light. When the wearer looks at an object, the meter instantly measures the distance and tells the actuators how to curve the lenses. If the user then sees another object that's closer, the distance meter readjusts and tells the actuators to reshape the for farsightedness. Hasan says the lenses can change focus from one object to another in 14 milliseconds. A rechargeable battery in the frames could last more than 24 hours per charge, Mastrangelo says.

Video of a liquid-based lens adjusting and readjusting its focal length. University of Utah engineers have created 'smart glasses' with liquid-based lenses that can automatically adjust the focus on what a person is seeing, whether it is far away or close up. Credit: Carlos Mastrangelo

Before putting them on for the first time, all users have to do is input their eyeglasses prescription into an accompanying smartphone app, which then calibrates the automatically via a Bluetooth connection. Users only needs to do that once except for when their prescription changes over time, and theoretically, eyeglass wearers will never have to buy another pair again since these glasses would constantly adjust to their eyesight.

Currently, the team has constructed a bulky working prototype that they put on display at last month's Consumer Electronics Show in Las Vegas, but expect to constantly improve the design to make them smaller and lighter. Mastrangelo said a lighter, more attractive pair could hit the marketplace in as early as three years and that a startup company, Sharpeyes LLC, has been created to commercialize the glasses.

Closeup of a liquid-based lenses that can automatically adjust the focus on what a person is seeing. Credit: Carlos Mastrangelo

Explore further: New eyeglasses allow you to adjust prescription yourself

More information: Nazmul Hasan et al, Tunable-focus lens for adaptive eyeglasses, Optics Express (2017). DOI: 10.1364/OE.25.001221

Related Stories

New eyeglasses allow you to adjust prescription yourself

May 31, 2012

(Phys.org) -- A new kind of eyeglasses is now available from a British company that allows the wearer to adjust the prescription anytime, anywhere, via small thumb-dials on the sides. Called, Eyejusters, the glasses make ...

A glimpse at the future? A smartphone in your glasses

October 1, 2012

(Phys.org)—No need to turn to your smartphone to check the time, look at your agenda or the weather forecast, read a text message or map a route in an unfamiliar city. All this information, and much more, will soon be displayed ...

Electronic spectacles coming to market soon

June 23, 2010

(PhysOrg.com) -- US company PixelOptics has invented electronic spectacles that can automatically change focus as you lower your head to read a book, and could spell the end of the bifocal.

Innovative device simulates cataract replacement experience

August 18, 2016

Today, patients with cataracts can choose from several types of artificial lenses, which are surgically implanted in the eye to replace cloudy lenses that obstruct vision. A new vision simulator could help these patients ...

Is the end in sight for reading glasses?

October 16, 2015

A University of Leeds researcher is developing a new eye lens, made from the same material found in smartphone and TV screens, which could restore long-sightedness in older people.

Recommended for you

How community structure affects the resilience of a network

June 22, 2018

Network theory is a method for analyzing the connections between nodes in a system. One of the most compelling aspects of network theory is that discoveries related to one field, such as cellular biology, can be abstracted ...

The pho­to­elec­tric ef­fect in stereo

June 22, 2018

In the photoelectric effect, a photon ejects an electron from a material. Researchers at ETH have now used attosecond laser pulses to measure the time evolution of this effect in molecules. From their results they can deduce ...

Water can be very dead, electrically speaking

June 21, 2018

In a study published in Science this week, the researchers describe the dielectric properties of water that is only a few molecules thick. Such water was previously predicted to exhibit a reduced electric response but it ...

9 comments

Adjust slider to filter visible comments by rank

Display comments: newest first

antialias_physorg
3.7 / 5 (3) Jan 25, 2017
Seems to not correct for astigmatism, though.
Eikka
5 / 5 (2) Jan 25, 2017
Seems to not correct for astigmatism, though.


Most people with age related eyesight problems don't have astigmatism, which is why you can get reading glasses for a dollar at the gas station, while people with nearsightedness usually have to get prescription glasses fitted.

It would be interesting if eyewear were sold like they used to in the olden days when a travelling lens grinder would come around and you'd pick up glasses from his box until you found one that suits your eye.
DonGateley
3.7 / 5 (3) Jan 25, 2017
Eikka, what you say about people with astigmatism not becoming myopic isn't true. Those getting them for a dollar at the gas station are just living with the residual astigmatism.
Guy_Underbridge
not rated yet Jan 26, 2017
Most people with age related eyesight problems don't have astigmatism
Only if most people don't have astigmatism. The two are not exclusive.
Eikka
not rated yet Jan 26, 2017
Most people with age related eyesight problems don't have astigmatism
Only if most people don't have astigmatism. The two are not exclusive.


Let's put it this way: most people don't have astigmatism bad enough that it would bother them, ergo as they get older they simply get farsighted and only need simple positive diopter glasses to see close up, which are easy and cheap enough to manufacture in bulk.

People with nearsightedness have a born-in fault in the way the eyes grow, which typically results in other issues such as astigmatism at the same time, and they need to be wearing the lenses all the time to see, so they have to be made better and for their specific lens geometry or it would result in poor vision and migranes.
Guy_Underbridge
not rated yet Jan 26, 2017
Sorry E, but they're different issues IMO. Far/Nearsightedness is the curvature of the cornea in relation to the length of the eye, causing blurriness beyond or before a given distance; whereas astigmatism is a sphericity (elliptical) defect of the cornea, causing blurriness at all distances.

Either way, I don't think it would be a far stretch to have these type of glasses correct for astigmatism anymore than they would need to correct for near- or farsightedness.

I think the bigger issue would be when the IR sensor locks on something that isn't desired (fog, dirty window, etc).

TheGhostofOtto1923
1 / 5 (1) Jan 26, 2017
Cool. Dr Robato. Ever notice how an autofocus camera wanders about selecting focal lengths? I see chronic headaches.
antialias_physorg
not rated yet Jan 26, 2017
Either way, I don't think it would be a far stretch to have these type of glasses correct for astigmatism

The way I see the thing working (looking at the image) it looks like the change is only radial. I could see a setup where astigmatism is taken into account but that would either require a lens gemetry that is manufactured to the particular user's aberration (and would have to be remanufactured with every change) - or a vastly more complicated electrode setup.

Neither of which is a knock-out criterium, mind. With a bit more development I'm sure it's possible.
Claudius
not rated yet Feb 01, 2017
It would be a simple matter to install a fixed-focus lens to correct the astigmatism, since it will not change significantly with accomodation.

The reason why over the counter readers don't work for many people is that the eyes are not always in balance, that is the right eye correction differs from the left significantly. Large amounts of astigmatism are another factor. Plus the generally poor quality of the lenses and frames, and the "one size fits all" pupillary distance.

It would be interesting if these lenses could be aspheric.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.