The goal of this paper is to show the usefulness of various asymptotic formulae in numerical evaluation of the field distribution of divergent spherical wave at the aperture. An example of calculations illustrating the use of these formulae is quoted. The due illustrations are given for the observation point positions, where the respective formulae are valid.
Grazyna Mulak, Grazyna Mulak,
"Evaluation of the field distribution in the Fresnel diffraction region", Proc. SPIE 2169, Nonconventional Optical Imaging Elements, (12 October 1994); doi: 10.1117/12.190235; https://doi.org/10.1117/12.190235