More than 153 million people around the world with poor or no eyesight either don't have access to or can't afford vision correction, according to the World Health Organization (WHO). Ninety percent live in low- or middle-income countries, WHO reports, where optometrists are harder to come by and individually crafted lenses cost too much for many.
A British physicist wants to solve that problem. He has his sights set on the lofty goal of distributing one billion pairs of glasses, at $1 a pair, by 2020. Why so many? Josh Silver, a physics professor at the University of Oxford in England and the man behind the mission, isn't stopping at the WHO's definition of those who need vision correction. He's also including much of the world's vast age 45–plus population, who are subject to presbyopia: natural age-related vision deterioration.
"The story now is how you get there," Silver says of his goal.
The glasses, developed by Silver and offered by his company, Oxford-based Adaptive Eyecare, Ltd., are round plastic frames with lenses made of clear sacs of silicon oil (the sort most commonly found in vacuum pumps that also happens to have a high refractive index) sandwiched between two clear plastic circles. They're not un-Harry Potter–like in appearance, but their effectiveness lies in a simple fundamental concept.
They work on the same principle that the human eye and traditional glasses do; as the curve of the lens changes, so does its power. The two fluid-filled membranes between the lenses hold a little less than 0.6 cubic inch (10 cubic centimeters) of oil and are each connected to a tube and small syringe, which can be adjusted by turning the dials on each side.
As a wearer adjusts the dials he or she can control how much liquid is loaded into each sac (thereby custom forming each membrane's curvature); this fine-tunes the glasses to an individual's prescription. After the world comes into focus, the sacs are sealed off permanently with a small valve, and the adjusting mechanisms are removed. The glasses weigh about 1.7 ounces (48 grams) and each lens is about 1.5 inches (four centimeters) in diameter.
"If you look through a lens that can be simply adjusted," Silver says, "this allows you to correct your own eyesight."
The idea for the glasses was born in the 1980s, when Silver, who spent most of his professional career looking into quantum mechanics and quantum electrodynamics, became interested in optics and began toying with the idea of adjustable-strength lenses. He first tried the technology on himself to correct his myopic eyesight. Another Englishman, Martin Wright, attempted to commercialize a similar kind of adjustable liquid-filled specs in the 1970s, but Silver says Wright had problems with leaks and was never able to sell more than about a dozen specs. Silver has employed many of the same concepts that Wright used, but has appeared to make a pair that are sturdy enough for daily use.
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16 Comments
Add CommentHoly pants. That's thinking. Aesthetics can be tackled later. That's brilliant.
Reply | Report Abuse | Link to thisTechnical challenges are still present but I suppose it's better than nothing. Once they solve what to do about changes in shape due to temperature extremes (and the resultant change in prescription strength) this has the potential of becoming a very useful product for third world countries.
Reply | Report Abuse | Link to thisThat is really cool. I mean they're a bit ugly, but this is helping people who really don't have to money to be that picky about something that will help them see better. Plus I bet a few designs down the road and they'll look nicer.
Reply | Report Abuse | Link to thisflippin genius.
@Eyecare: There should be little or no change due to temperature. The silicon oil is insensitive to temperature changes - it's essentially the same fluid as that used in auto brake systems. The sac that contains the fluid and the clear plastic holding it in place are either too thin or thermally stable as well. I sense no change in my vision regardless of the temperature extremes I expose my prescription lenses to.
Reply | Report Abuse | Link to thisi could see this taking over the eyeglqss industry once the technology increases. i could also see them making bifocals, and other such adaptions to the lense, obsolete by putting a small moter and computer device in them to program the settings that are perfect for you. imagine if you are reading something and you have to look up at something far away and just pushing a button or switch on the frame and having it get clear within 1-2 sec.
Reply | Report Abuse | Link to thisI had another idea years ago. Maybe call it McGlasses or Supermarket Optometrist. The client uses a machine to do a self-test to select the settings that are best for them, one for diopters, one for angle and intensity of stigmatisms to be corrected. The machine selects two circular lenses (solid in this case) for each eye, with one of several standard curvatures on one side so they can be cemented together. With a drop of maybe epoxy and the proper angle for the stigmatic lens, the two lenses are snapped and glued into circular frames.
Reply | Report Abuse | Link to thisBut then this would be too efficient. We're supposed to be creating jobs instead of eliminating them.
It sounds good! But it maybe takes many years to come true.
Reply | Report Abuse | Link to thisThat is just amazing. As someone who comes from generations of eye problems I don't care what the frames look like. I would love the power to adjust my own eyeglasses in such a way. I thank the inventor for existing.
Reply | Report Abuse | Link to thisdibetic conditions can cause perscription of eyes to alter at times these selfadjusting glasses could be helpfull
Reply | Report Abuse | Link to thisdibetic conditions can cause perscription of eyes to alter at times these selfadjusting glasses could be helpfull
Reply | Report Abuse | Link to thisJust to note Dr Martin Wright's variable power eyeglasses were very clever at their time - the leak problem could have been solved I believe but what I was told was that disagreements between those taking the initiative forward meant that Dr Wright found it hard to continue. Wright's actual technology was rather different from mine however in that he used deflected plates rather than membranes. This tends to limit the range of power.
Reply | Report Abuse | Link to thisHow can I buy a box full of these? I am a Mennonite pastor (and a faithful reader of Scientific American) and I would love to raise the money in our Sunday school program to send to pastors and teacher in poor Mennonite communities in Africa and Asia. $20 bucks a pair is cheap and they could be shared in a family since they are adjustable. These glasses could change so much for the good.
Reply | Report Abuse | Link to thisGod bless this scientist, he is a genius who will some day be remembered with the ranks of Louis Pasture!
Good Idea
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Good Idea
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You know... If you offered a pair of these glasses for a monetary donation your cause would thus be greatly increased... Think about it. I would donate/buy a pair...
Reply | Report Abuse | Link to thisThanks for this informative post! It reminded me of my sister's place where she was able to get some good <a href="http://markdowneyewear.com">discounted eyewear in New York NY</a> and it was pretty cool!
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