Cheap "Liquid Glasses" Bring Clear Vision to the Poor

By Nina Bai | January 5, 2009 7:41 pm

glassesA retired physics professor is trying to bring clear vision to a billion of the world’s poor.  His strategy: eyeglasses with easily adjustable, fluid-filled lenses that cost just $1 a pair.  His goal: distributing one billion pairs by 2020.  The glasses would help schoolchildren learn how to read, fishermen to mend their nets, and women to weave clothing, he says.

According to the WHO, there are about one billion people in the world who would benefit from vision correction, most of them living in developing countries.  However, in places like sub-Saharan Africa, where people make less than $1 a day and there is roughly one optometrist per one million people, glasses are an impossible luxury.

Josh Silver came up with the idea of fluid-filled lenses over 20 years ago while he was still a professor of physics at Oxford University.  The glasses contain a clear sac in each lens that can be filled with silicone oil.  Adjusting the power of each lens is as simple as changing the amount of silicone oil in the sacs, which can be done with a syringe through the arm of the spectacles (a process reminiscent of adjustable breast implants).  Adjustments can be made by the wearers themselves and the power can range from -6.00 to +6.00 dioptre. The shape-changing lenses actually operate similarly to the natural lens of the eye, although in the eye, the shape of the lenses is controlled by muscles.

Silver has been perfecting the technology, trying to bring costs down, and has started a company called Adaptive Eyecare to develop and distribute the glasses.  Already, 30,000 pairs have been distributed in 15 countries.  He is forming partnerships with humanitarian programs and governments to ramp up distribution to 100 million pairs annually within the next few years.   Meanwhile, he’s also tackling another concern: how to make the clunky glasses look less geek and more chic.

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Image: flickr / kaex0r

MORE ABOUT: eyeglasses
  • Samsam

    An article in Popular Science in the 1970s or 80s described a very similar invention, except there was a thumb-wheel on each earpiece that moved a piston in and out (along the length of the earpiece) alowing the user to change focus. As a 48-year old with natural lenses that no longer adjust, this would be a wonderful product.

  • Uncle Al

    Water refractive index = 1.3333, PDMS silicone oil is 1.406, Nujol mineral oil is 1.477, DC 550 silicone oil is 1.4935, soda lime glass is 1.518, diphenyl ether (commercial heat exchange fluid when biphenyl is added) is 1.579. Santovac polyphenyl ether fluids run 1.62-1.67 and higher (Santovac 5 at 1.630, pour point = 4 C). The eyeglasses need not be chunky. Add a radial tensioner for astigmatism correction.

    Silicone oils reptate through polymer membranes, constitutng a slow virtual leak.

  • M Yellen

    If all the frames were designed to hold snap in round plastic lenses you could most likely produce the same quality vision correction with existing technology for about $1.00. Pupillary distance would be a problem in the higher corrections but compared to no correction at all it would not be a bad compromise.

  • cheap glasses

    I think so if you really can offer such good glasses, you will have good chances to make good money.

  • bn

    These glasses would also be beneficial to poor people in our country as well.

  • joe resciniti

    where can i purchase some of these, igo to the amazon monthly some one is selling these same glasses for over 800.00 dollars

  • Jan Bradley

    Retired LT Gen John A. Bradley and Mrs. Bradley airlift humanitarian aid to Afghanistanthrough Denton USAID and will be building schools in remote villages.
    Have never seen but three or four people in Afghnanistan with glasses.
    There is a huge need for them there.
    How can we get them?

    Thank you
    Jan Bradley

  • Pingback: Techs for Planet - E-focals: Electric Eyeglasses Are the New Bifocals | Discoblog()


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