Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Question about optics (diffraction)

  1. Dec 6, 2005 #1


    User Avatar

    I was working out a practice test on optics and was a little confused about how to tackle this problem:

    If you illuminate a hole and project the resulting pattern on a screen- as you decrease the hole size, the screen pattern gets smaller initially and then ultimately begins to grow larger. Why is this? Derive a formula for the screen pattern diameter as a function of the hole size, distance between screen and hole and the wavelength.

    I know the effect is diffraction, but deriving the mentioned relation is giving me trouble. I was thinking of using the kirchoff integral theorem, and then perhaps carrying out an integral over a rectangular aperature; but maybe that is overkill. Is their an easier way to start thinking about this?
  2. jcsd
  3. Dec 6, 2005 #2


    User Avatar
    Science Advisor
    Homework Helper

    Is this considered introductory physics nowadays? :eek: I must be getting old.

    Maybe this will help a bit:
  4. Dec 6, 2005 #3


    User Avatar

    Lol, yeah this was probably a mispost; i got a chance to check the other posts in this section and realized it at that point. Thanks for the reference though galileo.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook