Modeling laser beam diffraction and propagation by the mode-expansion method.
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.
University of North Carolina at Charlotte, Center for Precision Metrology, 9201 University City Boulevard, Charlotte, North Carolina 28223, USA. jjsnyder@uncc.edu
James J
JJ
Snyder