Purchasing new hardware? Read our latest product comparisons

TruFocals eyeglasses feature adjustable focus


October 12, 2010

TruFocals can be instantly focused by the user, thanks to flexible lenses

TruFocals can be instantly focused by the user, thanks to flexible lenses

Image Gallery (6 images)

If you wear bifocal or even trifocal eyeglasses, then you will know what a hassle it can be having to tilt your head up to see things that are nearby. The areas of image softness or distortion can also be distracting, and even cause nausea or headaches in some users. Using multiple pairs of single-vision glasses gets you around these problems, but introduces the problem of... well, of carrying around and using multiple pairs of glasses. TruFocals, however, allow users to wear one pair of glasses for near-, distance- and mid-vision, without having different focal areas within the same lens at the same time. Instead, users actually focus the glasses by hand, not unlike a pair of binoculars.

TruFocals have three optical surfaces for each eye. On the front is a rigid lens, in the user’s distance prescription. Behind that is a flexible lens, and behind that (closest to the eye) is a rigid, optically-neutral lens. In the space between the flexible and neutral lenses is an optically-clear fluid. By moving a slider on the bridge of the glasses, users change the shape of the flexible lens, by pumping fluid in or out of the space behind it. This allows them to instantly refocus the glasses on the fly, as the situation warrants.

The technology is much like that which retired physics professor Joshua Silver is using in his Adspecs eyeglasses for people in developing nations, in which flexible lenses are bowed out or sucked in by the injection or withdrawal of clear fluid behind them. In the case of Silver’s glasses, however, the lens distortion is set once for each client, then sealed in place – recipients can’t change the shape of the lenses back and forth, depending on whether they want reading, distance, or mid-range glasses.

TruFocals are said to work from temperatures of -4C (25F) to 52C (125F), so their adjustability outdoors in cold winter climates is certainly limited. Some potential users might also wonder about the bother of having to reach up and move the focus slider. While the company claims that it becomes second nature, there could certainly be situations – such as where a user’s hands are occupied or dirty – in which it wouldn’t be possible.

The glasses are also only available in the one style, so if you don’t like it, you're stuck. They are said to be similar in weight to regular glasses with conventional frames.

You can buy TruFocals through the company website, for the eyebrow-raising price of US$898.

Via InventorSpot.

About the Author
Ben Coxworth An experienced freelance writer, videographer and television producer, Ben's interest in all forms of innovation is particularly fanatical when it comes to human-powered transportation, film-making gear, environmentally-friendly technologies and anything that's designed to go underwater. He lives in Edmonton, Alberta, where he spends a lot of time going over the handlebars of his mountain bike, hanging out in off-leash parks, and wishing the Pacific Ocean wasn't so far away. All articles by Ben Coxworth

eyebrow raising price, no sheet, nice idea though

Bill Bennett

If the frames are going to be that ugly, they\'ll be a hard sell. Did they fashion them out of old pop can bottoms?

Carol Wilkerson

Because of the nature of the adjustable-diopter lens, the lens must be perfectly round and the center of each lens must be exactly in front of the appropriate pupil. This limits the styling to round lenses and limits the lens sizes available.

Because the lens center-to-lens center metric must match the PD (pupillary distance) the frames must either come in a very wide variety of sizes or be custom-made for each wearer- thus the very proud price. On the other hand, I\'ve paid over $400 for bifocals, so the price isn\'t that far out of whack.

But I\'ll stick to buying my eyeglasses from online vendors- for as little as $25 plus postage I can get prescription bifocals delivered to my house, usually within 2 weeks.

William Lanteigne

How well do the glasses handle astigmatism?


Add Autofocus driven by where your eye is looking at and something like those ultrasonic silent motors in canon lenses. Gives you true automatic, always in focus eyewear!

Your frame could be the polymer battery, and the glass surface (or the fluid inside) can provide photovoltaic power to keep it charged.

Maybe I should patent the idea!


I came up with a variable lens technology and made it auto focus some 8 years ago, unfortunately one thing after another, I was unable to get it patented. I am glad someone else has come up with the same idea, it just needs a one component upgrade and it will be auto adjusting! The invention I want to patent now is a true 3d Active Holographic Projection system ( though in its current form is a bit limited in size and distance) It would be like a desktop screen except its 3d and you can wave your hand through it. It wouldn\'t be all that hard to also develop a 3d sensing system so you can interact with the hologram.

Oliver Seet

@ guptad42

Maybe you should


I want one, as soon as the price drops, but it got me to wondering why is it that I can\'t adjust the focus on my computer to be able to read it without wearing glasses?

Post a Comment

Login with your Gizmag account:

Related Articles
Looking for something? Search our articles