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A puzzle on light diffraction

  1. Dec 13, 2009 #1
    Hello!
    Recently, I'm always thinking about why diffraction effects are generally most pronounced for the size of the diffracting objectsis that is on the order of the wavelength. How about a relatively bigger object?

    I try to find it everywhere I can but failed. So anyone can help? Thanks!
     
  2. jcsd
  3. Dec 13, 2009 #2
    Can you explain a bit more? what kind of objects are you talking about?
     
  4. Dec 13, 2009 #3
    such as bending of waves around small obstacles and the spreading out of waves past small openings.
    A famous example:single-slit diffraction. If the slit is pretty large, then I guess there is no abvious diffaction.
     
  5. Dec 13, 2009 #4

    jtbell

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  6. Dec 13, 2009 #5

    Andy Resnick

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    The wave propagation of light is parameterized in terms of a specific length scale (the wavelength). That means the problem is in terms of ratios: wavelength/distance, for example. If wavelength/distance <<1, the appropriate diffraction term is small, while if wavelength/distance >>1, it's large. Note that 'distance' can be propagation distance, the size of a scattering object, or aperture diameter...

    Does that help?
     
  7. Dec 14, 2009 #6
    I think you are right, thank you very much!
     
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