The physical-realizability issues of scalar focus wave modes that are solutions of the homogeneous wave equation with the boundary data exp(−r2w0−2) given on a characteristic are addressed. The Gaussian beams are solutions of the paraxial equation with the same boundary data in a fixed plane. A comparison of these two situations suggests that the focus wave modes can be approximated by giving the exponential exp(−r2w0−2) on some moving plane. This suggestion is implemented.
© 1992 Optical Society of America
Original Manuscript: May 23, 1990
Revised Manuscript: August 5, 1991
Manuscript Accepted: August 18, 1991
Published: January 1, 1992
Pierre Hillion, "Approximation of the scalar focus wave modes," J. Opt. Soc. Am. A 9, 137-141 (1992)