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Power of Sun Glass

  1. Jul 15, 2012 #1
    Please someone tell me why sun glasses have no power,though they are curved.......
     
  2. jcsd
  3. Jul 15, 2012 #2

    CWatters

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    They do very slightly distort light but because both surfaces are curved and parallel and the material thin the effect is minimal. Like looking through a window.
     
  4. Jul 15, 2012 #3

    Vanadium 50

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    You can get prescription sunglasses, which do have 'power'.
     
  5. Jul 16, 2012 #4

    sophiecentaur

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    A lens works because of a difference in curvature between the sides. A curved sheet of glass with parallel sides is neither concave nor convex and does not act as a lens. This statement only really applies for relatively thin glass that isn't 'very' curved. Extremely thick / curved glass sheets will distort images, although they don't behave like simple lenses either.
     
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