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Old 08-19-2010, 06:15 PM
 
Location: Canada
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Thanks anon chick. No I have no vanity issues with it.
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Old 08-20-2010, 10:15 AM
 
Location: Victoria TX
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There is a lens inside your eye, similar to a convex magnifying glass. It is soft and pliable, and the muscles of your eye can press around the edges of it, to change its shape. That's what is happening when you stop reading and look out the window. Those muscles relax, allow the lens shape to revert to normal, and your focal distance to set on infinity.

When you are looking at something less than about 20 feet, your eye muscles compress the edges of that soft lens, like focusing binoculars for varying distance. But as you get older, that lens becomes more and more rigid, and your eye muscles can no longer apply enough force to it to significantly reform its shape, so you cant focus on nearby objects any more. Then you need reading glasses, to make the optical adjustment that your eyes can no longer make.

Eventually, cararacts are likely to form on your lenses. Your ophthalmic surgeon will take your lenses out and throw them away, since they are now becoming opaque, as well as hard. He'll replace them with a hard lens, which will always have the same optical properties, and the eye muscles responsible for changing the shape of the lens no longer do anything at all. The replacement lens will probably be designed for distance vision, and you will likely see nearly 20/20 at a distance, without glasses. But you will need glasses for reading, and probably also a different Rx for TV watching.
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