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Science Technology

User-Adjustable Glasses 43

Posted by timothy from the would-like-to-test-these dept.
DrLudicrous writes "An Oxford University professor has come up with a way to manufacture adjustable glasses. The lens is made up of silicone oil, which when added or removed changes the curvature, and thus the strength of the lens. Apparently, these are inexpensive enough to distribute to the poor people's of rural Ghana, who do not have the opportunity to see a doctor, let alone afford conventional glasses."
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User-Adjustable Glasses More

User-Adjustable Glasses

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  • cool (Score:2, Insightful)

    by redshift-systems ( 622407 )
    I'd like to get a pair of those, that way you can share them between family members, or swap between drivers on long trips. What ever happened to the prescription windscreen anyeway?

  • Donate. (Score:5, Informative)

    by Trusty Penfold ( 615679 ) <jon_edwards@spanners4us.com> on Monday December 09, 2002 @11:44PM (#4851320) Journal
    Don't forget to donate [peneyecare.com] your old glasses to charity as well!
    • You know, I would, but (1) I tend to break my glasses (or, rather, my kids do) and (2) I'm not much shortsighted but have a strong astigmastism. That's where you have a distortion at a specific orientation, different for every person and every eye. If that orientation is off by a little, say your overly-round lenses turn, oh what a headache. But the orientation is not generally user-adjustable.

      So I'm hesitant to donate, while also thinking of the plight of astigmatic folks in developing countries. My vision is no less deficient than that of someone classically short/farsighted, but significantly harder to fix. Perhaps this could help? No, pity ("The glasses do not correct astigmatism.")

      Well, cool invention all the same. Now who will fund it?

      • Re:Donate. (Score:3, Informative)

        by stefanlasiewski ( 63134 )
        The eyeglass donation places will be able to make good use of your frames.

        The lenses are often discarded , since few people have the exact same vision.
        • Good point, thanks. Unfortunately my frames at the bitter end are usually held together by tape and glue....

          At least not as many people in developing nations are ruining their eyes with books, televisions, and monitors. I wonder about the problem noted in the article, that if anything a larger fraction of these individuals may have more serious disorders such as glaucoma that need treatment....

    • Re:Donate. (Score:1, Funny)

      by Anonymous Coward

      I could donate my current glasses. The threads are stripped on the screw that holds the right lens in. It's now held in by a strand of wire stripped from a CAT5 cable. These third world nations could be supplied with our used glasses but to maintain them they would also require advanced technology such as needlenosed pliers, computers and a reason to have CAT5 cable such as the internet. However, once they get all those then they will be too busy to get around to getting a decent pair of glasses.

    • I can't, I got new glasses because my old ones got destroyed (car accidents, commando games in the woods). Now I have glasses with an all-titanium frame...whatever breaks those will also break me!

  • Thats funny... (Score:3, Informative)

    by Izanagi ( 466436 ) on Monday December 09, 2002 @11:59PM (#4851442) Journal
    I swear I saw these 6 years ago.
    hmmm...

    "Silver started his own company, called Adaptive Eyecare in 1996 to manufacture and market the glasses."
    -Seeing Is Believing [go.com]

  • Eye problems (Score:2, Insightful)

    by Bob MacSlack ( 623914 )
    I'm just going to admit I don't know what im talking about, but isn't it possible to cause actual harm to your vision by wearing glasses that are too strong a perscription? That and headaches and other things that you could potentially cause to yourself.

    • Re:Eye problems (Score:3, Informative)

      by JSCarr ( 312656 )
      Yes, it's very possible to cause harm to your vision by wearing glasses that are either too strong or too weak. Any optometrist will tell you that the drugstore rack reading glasses should be banned. Another less obvious hazard is the quality of the materials often used to make these glasses. The cheap ones really do not have shatter-proof lenses. Not a good thing.

      • Re:Eye problems (Score:3, Insightful)

        by Simon Field ( 563434 )


        Just what mechanism are you proposing for this damage?

        If what you say were true, then bifocal lenses would also damage your eyesight. Or simply taking off your glasses would damage your eyesight.

        Don't be silly. There is no harm in the drugstore reading glasses, any more than there is in using a magnifying glass to read. All they do is make the image you see appear as if the object were closer to you. If that can damage your eyesight, then don't ever look at things too closely.

        As for shatter-proof reading glasses, while they might be a good idea, I generally don't engage in the kind of activity that would shatter my glasses while I am reading.

        • Eyestrain can definately occur from wearing glasses that are too strong. Anyone who has ever worn glasses knows this; when you first put on a new prescripton, your eye muscles get sore from the sudden dramatic adjustment. Or, you can get the same effect by reading a computer screen from a foot away (if you're nearsighted) with your correct prescription glasses. That's why I use my old, weaker prescription glasses when I'm working at my computer. It's easier on the eye muscles.

          • Re:Eye problems (Score:3, Interesting)

            by Simon Field ( 563434 )


            You are talking about eyestrain.
            The thread was talking about eye damage, which is an entirely different thing.

            People who need reading glasses are mostly those of use whose natural lens is no longer flexible enough to refocus well, due to age. Without any reading glasses, we would be under eyestrain conditions all the time, since we would be trying to focus the natural lens by muscle power, and it can't flex enough.

            With reading glasses, I can focus on something close up, and I can take them off to see far away. People with bifocals do this by lifting their head, and yet I don't see people arguing that bifocals cause eye damage.

            Reading glasses don't cause eyestrain. They prevent it.

            Your point about glasses that are too strong is right on the mark, and argues my case that people should be able to adjust their lenses without a doctor visit. If you bought the wrong reading glasses at the drug store, return them for the right ones.

            Or just turn the screw on the adjustable version.

        • Or simply taking off your glasses would damage your eyesight.


          Doesn't it? I'm sure I was told that as a kid. I wish I'd listened too.

          - Chris
        • Here's the mechanism:

          When an out of focus image is presented to the retina it stimulates growth of that part of the eye resulting in a change in eyeball shape. This is the normal mechanism by which the lens-retina system forms and maintains a system that can focus in an organism over its lifetime. However it's not a perfect mechanism and using the wrong lenses can seriously mess it up.

          This, incidentally, is one of the reasons for myopia in our modern society. The eye is adjusting to long periods of close up work to which it is not well adapted. This causes the eye to grow into a maladapted shape.

          • When an out of focus image is presented to the retina it stimulates growth of that part of the eye resulting in a change in eyeball shape. This is the normal mechanism by which the lens-retina system forms and maintains a system that can focus in an organism over its lifetime[...]

            This, incidentally, is one of the reasons for myopia in our modern society. The eye is adjusting to long periods of close up work to which it is not well adapted. This causes the eye to grow into a maladapted shape.

            That's interesting, intriguing, and could quite possibly even be correct. Do you have any links to further evidence?

            And does this theory have anything to say about the causes of astigmatism?

            • It was a book on evolution and human health that I no longer have and no longer have a reference to. However, if you do a web search on myopia and evolution you'll find quite a few references which you can then chase up to find a trustworthy source. There's quite a bit of unreliable material on this subject so definitely don't trust just web sites!
  • When my mother picked up a pair of those reading glasses (read: wearable magnifying glasses) a time back, she found her eyesight without them was getting progressively worse, to sum it up briefly. If this can happen, what is there to state that these glasses would be a Good Thing? Like another poster stated, the wrong prescription can screw up your eyes, so wouldn't putting simply increased magnification over the eyes cause more problems?
  • Previously, it was a delicate corneal inversion procedure... a multi-opti-pupil-optomy [imdb.com].

    Ain't no man going to take that route with me!

  • What the... (Score:2, Informative)

    by edgecrusher ( 533227 )
    Hmm, I seem to remember seeing these on "Tommorrow's World" some years ago; exact same invention, and probably the same inventor.. I don't recall.

  • I love this idea! (Score:3, Insightful)

    by Simon Field ( 563434 ) on Tuesday December 10, 2002 @01:55AM (#4852064) Homepage


    First, I love the idea of giving glasses to people who can't afford them. Often the reason they can't afford them is that without good eyesight they can't make a better living.

    I also love the idea of adjustable eyesight. This is what the eye is designed to do naturally. The lens in your eye is adjustable until you reach my age. Just not adjustable enough.

    I love the idea of letting people fix problems themselves without expensive professionals. The idiot in the article who complained that the people need to see an optometrist in case there is something worse wrong with the guy is being atrociously patronizing. When I cut my finger I don't go to a doctor in case I might also have cancer.

    Being in charge of the adjustment means that if I get it wrong, I can fix it right away. How many of us have had to go back to the optometrist to get new glasses because they got the prescription wrong the first time? Or how many of us just put up with bad correction and only discovered the problem when the next pair of glasses fixed it?

    But I also love the idea because of the other things we can do with these glasses once they become widely available. Get two pair, and have adjustable binoculars (just separate the two by a few inches). Or have cheap adjustable focus for small telescopes or microscopes. Or lightweight autofocus cameras.

    Suppose the adjustment was really fast and easy. Now your regular glasses can be reading glasses with a touch to your temple.

    I love this idea.

    • As someone who has various eye problems in his family, I must disagree. Seeing an eye doctor on a regular basis can save your eyesight. Often, diseases of the eye, if caught soon enough can be cured. If left until symptoms become obvious, it's often too late to restore, or even save vision. This is probably even more of a problem in the third wolrd, where access to the latest hi-tech surgery techniques may be lacking.


      I really like the idea of these glasses, though. I see them as a force-multiplier. A single optometrist could examine and correct a whole villiage in a few days, without having to wait for prescriptions to be filled in some optical lab somewhere. The benefits to the population would be immediately felt, and those who need additional care could be helped in the time that is saved from all the rest.


      • You missed the point.

        Of course regular visits for checkups can help find all kinds of problems.

        But we don't force you to get an engine checkup every time you fill the tank. We don't require a doctor visit for a bandaid. We don't even require an optometrist visit to buy the reading glasses at the drug store. Why would we keep poor people from improving their eyesight by forcing them to travel miles to an expensive optometrist to get something they can adjust by themselves?

        Give the poor people the same choices you have. Let them decide whether the money goes into checking for glaucoma or into feeding the baby.

    • How much of a focal-point change can be realized, and how controllable is the shape of the lens? Moving on past simple focal devices on binoculars and cameras, I can see this being used to make multipurpose devices --- assuming that the curvature can be adjusted with great enough detail. Assuming a deformable enough lens, it could be possible (with a light-amplification method, as the aperture requirements vary greatly between these devices) to create a gadget that combined the functionality of a low-power microscope and monocular into one portable tube. It has to be easier to alter the focal specifications of a liquid-based lens regardless --- autofocus could be taken to a completely different level with some work.
  • The thing I worry about is how delicate the glasses look. I imagine the people who get these will probably take better care of them then I do of my glasses, but accidents are bound to happen and how durable is that thin polyesther membrane going to be? Judging from the picture provided the whole apparatus looks like it would last about six months of normal wear and tear.

  • Several Misgivings (Score:4, Interesting)

    by Tsar ( 536185 ) on Tuesday December 10, 2002 @06:54AM (#4853184) Homepage Journal
    I agree with these gentlemen:

    But not everyone embraces the idea. "They will prevent some people from coming to the hospital, where we might discover more serious problems," said Dr. Samuel Asiedu, general secretary of the Ghana Optometrists Association. Dr. Ababio-Danso, the ophthalmologist in Agogo, also notes that many Ghanaians are unfamiliar with glasses and do not know how to care for them or clean them.

    Also, I was dumbfounded by this quote:

    Nor is it clear how durable the glasses will be, or how long they will retain their prescriptive power, since the oils or the shape may deteriorate over time.

    Reading from the company's website [adaptive-eyecare.com]: "The company was founded by Oxford physics professor Joshua Silver in 1996 and is based in Oxford and London. The company has developed prototype adaptive spectacles that can correct both far-sighted and near-sighted people, and these spectacles have been trialled in several countries in Africa and Asia."

    In six years of operation, and after testing in several countries, how would they still be unsure of their products' durability or focus-holding ability?
  • I saw this on tomorrow's world (BBC TV) years ago, it must have been the early 90's...
    They were demonstrated on people in africa too, so this story is really really old.
  • I've just been re-reading Dune and didn't quite know what they meant by "oil lens binoculars." Now I do. I know Herbert wasn't the first person to think of them, but it's interesting to see another science fiction gadget appear in the real world.
    • Oil-lens binoculars? I've heard of oil lens microscope (drop of oil on the slide cover, move the lowest lens in to touch the drop) but not binocular. How and why?

    • Aren't Luky Skywalker's binocs supposed to be oil lens models in the original Star Wars: A New Hope (episode 3). IIRC, this was mentioned in the old novelization.
      • [geek]ANH is episode 4!!!!!, and electrobinoculars [starwars.com] are electronic image enhancers, they have nothng to do with oil. fun fact: electrobinoculars were never used in the movie, but were in a cut scene, luke originally watched the battle between the Tantive IV and Devastator above tatooine, that scene should be in the ultimate edition dvd. [/geek]But i havn't read the old novelization :p
  • Before you can't.

    http://www.newscientist.com/news/news.jsp?id=ns9 99 93082

    Excerpts:
    As a result, the team reports in a paper that will appear in Vision Research, on average the vision of the 47 children with undercorrected myopia deteriorated more rapidly than those given full correction (see graph). Yet full correction has long been out of fashion. "I had to go back to 1938 to find someone in the literature saying a full correction should be made," O'Leary says.

    O'Leary's message to doctors, patients and parents is unequivocal. "No glasses is the worst option of all," he says. "But don't undercorrect. Go for full correction."

    ---
    (I'd dare say overcorrection will screw your eyes as well).

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