For eyeglasses, special lenses which are a sandwich of stiff yet flexible clear plastic. Between the discs is a thin gap filled with clear fluid. Injecting fluid into the gap causes the lenses to bulge slightly, making them more convex. Conversely, withdrawing fluid makes them more concave. An IR rangefinder (like in cameras) in the temple senses the distance to objects, and controls a micropump to transfer the right amount of fluid from a reservoir. Thus, the correction can be optimized for objects at a particular distance.-- rmutt, May 10 2000 Glance Direction Specs http://www.halfbake...Specs#963574831-2-1How to "measure the angle". [egnor, May 10 2000, last modified Oct 04 2004] TED: Josh Silver: adjustable liquid-filled lenses (2009) http://www.ted.com/...led_eyeglasses.htmlWithout the autofocus / high-tech stuff - in fact, Silver's design comes out of trying to get vision to people without an optometrics infrastructure. [jutta, Jun 15 2010] Superfocus http://superfocus.com/home2/Adjustable refractive power eyeglasses [whlanteigne, Apr 11 2013] An interesting idea, but I think it'd give one headaches pretty quickly. Your eyes are always changing focus, a little at a time. If the glasses tried to match, they'd always be a bit out of step, and if they had a built in lag, they'd still be incorrect for what you wanted. At least that's what it seems like to me...-- StarChaser, Aug 04 2001 Worse still, you get to enjoy being totally out of focus when you are driving and the range finder is detecting and focusing for the windshield only a foot in front of your face.-- eyeguy, Jan 23 2004 Can't see the point. Your eyes already do that...hopefuly (-).-- PauloSargaco, Mar 18 2004 No help for us astygmatics still...-- goatfaceKilla, Jul 06 2006 Baked, bigsleep? Naw, rmutt beat them by years. There ought to be an HB award for ideas that get shamelessly stolen by college professors. A golden goose egg, maybe.-- ldischler, Jul 07 2006 Now baked as a consumer product: Superfocus glasses. See link.-- whlanteigne, Apr 11 2013 random, halfbakery