Abstract
A Gaussian beam weakly diffracted by a circular aperture can be approximated in the far field by another Gaussian beam with slightly different characteristics. Equations giving the intensity, the divergence, and the radius of the modified beam are derived in simple practical form for experimentalists. These approximated formulas show that, even in the case of negligible power losses through the aperture, the diffracted beam characteristics may appreciably differ from those of the incident beam. In a first approximation, diffraction effects may be ignored only if the ratio a/r0 of the aperture radius a to the 1/e intensity beam radius r0 in the aperture plane is larger than 3.
© 1982 Optical Society of America
Full Article | PDF ArticleMore Like This
Guoquan Zhou
Opt. Express 17(10) 8417-8422 (2009)
J. P. Crenn
Appl. Opt. 21(24) 4533-4541 (1982)
Kazumasa Tanaka, Nobuhiro Saga, and Hiromu Mizokami
Appl. Opt. 24(8) 1102-1106 (1985)