1. PF Contest - Win "Conquering the Physics GRE" book! Click Here to Enter
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Gaussian beam passing through a circular aperture

  1. Feb 14, 2010 #1
    Hi all,

    when I have a Gaussian beam passing through a circular aperture:
    What should be the far field (Fraunhoffer's) distribution?

    Thanks in advance,
  2. jcsd
  3. Feb 14, 2010 #2

    Andy Resnick

    User Avatar
    Science Advisor
    Education Advisor

    The far-field diffraction pattern is the Fourier transform of the field at the aperture. So, it depends on how over- or under-filled the aperture is by the beam. If the beam size is much larger than the aperture, the far-field pattern is close to an Airy function. If the beam severely underfills the aperture, the far-field pattern is nearly a Gaussian. Intermediate cases will present intermediate results- the transform of circ(r/D)*Gaus(ar) = Somb(D*u) # Gaus(u/a), where '#' is the convolution operator, etc.
  4. Feb 14, 2010 #3
    Thank you!

Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Similar Threads - Gaussian beam passing Date
A Multi Gaussian beams explanation Dec 29, 2016
I Gaussian beam interference May 13, 2016
A Multi Gaussian beams? Apr 13, 2016
I Divergence and transversal extension integral definitions Apr 6, 2016
Cubic phase modulation of a gaussian beam Nov 23, 2014