If you for some reason don’t have reading glasses that you need and your arm isn’t long enough to read your watch, it’s time you got this thin, snap-on, variable lens.

The lens is a liquid-filled, flexible, plastic disc surrounded by a metal strap similar to a hose clamp. When mounted, the watch with lens appears conventional, but by pinching on the tabs, one compresses the lens perimeter, causing its surfaces to become convex and enabling you to read the time.
-- FarmerJohn, Nov 10 2002

How To Build A Time Machine, Scientific American,9/02 http://www.sciam.co...4A-90FB809EC5880000
...a whimsical gift of a link to FarmerJohn... [hollajam, Oct 05 2004, last modified Oct 21 2004]

Large Digital Watch for Vision Impaired http://www.sightcon...m/iclarnumdigw.html
...and I've seen bigger ones than this. [mr2560, Oct 05 2004]

I believe Bausch & Lomb (optical suppliers) are developing an intra-ocular lens implant that works using a similar principle...that way, when people have their cataracts extracted, they get back the use of their eyes' accommodation system. Obviously, you don't squeeze the IOLs with your fingers, instead the eye's ciliary muscle does the job.
-- vigilante, Oct 06 2004



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