In the mode-expansion method for modeling propagation of a diffracted beam, the beam at the aperture can be expanded as a weighted set of orthogonal modes. The parameters of the expansion modes are chosen to maximize the weighting coefficient of the lowest-order mode. As the beam propagates, its field distribution can be reconstructed from the set of weighting coefficients and the Gouy phase of the lowest-order mode. We have developed a simple procedure to implement the mode-expansion method for propagation through an arbitrary ABCD matrix, and we have demonstrated that it is accurate in comparison with direct calculations of diffraction integrals and much faster.
© 2007 Optical Society of America
Original Manuscript: January 31, 2007
Revised Manuscript: April 26, 2007
Manuscript Accepted: May 18, 2007
Published: July 9, 2007
James J. Snyder, "Modeling laser beam diffraction and propagation by the mode-expansion method," Appl. Opt. 46, 5056-5061 (2007)