Posted on 06/21/2010 12:16:31 AM PDT by LibWhacker
Traditional bifocals could become a thing of the past with the invention of electronic glasses that automatically adjust to let their wearer view objects at different distances.
The spectacles, which are due to be launched in the US this year and the UK next year, use lenses that change their strength when a small electrical current passes through them.
A layer of liquid crystal sandwiched inside each lens alters its refractive properties according to the current applied, adapting the focal length according to where the wearer is looking.
Traditional bifocals, which use two lenses of different strengths in front of each eye, have been used by people who are struggle to focus on both near and far objects ever since they were believed to have been invented by Benjamin Franklin, the American statesman, in the 1780s.
But some users complain of headaches and dizziness while the small field of view forces them to move their heads while reading.
The electronic glasses, which have been developed by US firm PixelOptics, can be adjusted manually to view objects at different distances by pressing a button on the side of the frames.
Unlike traditional bifocals, which only allow the wearer to focus "near" or "far", the electronic lenses have a range of in-between settings.
(Excerpt) Read more at telegraph.co.uk ...
Makes me want a quiet spot, a candle, and an old dusty tome.
I’m reminded of the first LED digital watches of the 70’s. You needed two hands to do what you used to do with one.
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