title: Fresnel diffraction and fractal patterns from polygonal apertures.
abstract: Two compact analytical descriptions of Fresnel diffraction patterns from polygonal apertures under uniform illumination are detailed. In particular, a simple expression for the diffracted field from constituent edges is derived. These results have fundamental importance as well as specific applications, and they promise new physical insights into diffraction-related phenomena. The usefulness of the formulations is illuminated in the context of a virtual source theory that accounts for two transverse dimensions. This application permits calculation of fractal unstable-resonator modes of arbitrary order and unprecedented accuracy.
authors.affiliation: Joule Physics Laboratory, Institute for Materials Research, School of Computing, Science and Engineering, University of Salford, Salford M5 4WT, UK.
authors.forename: J G
authors.initials: JG
authors.lastname: Huang
authors.forename: J M
authors.initials: JM
authors.lastname: Christian
authors.forename: G S
authors.initials: GS
authors.lastname: McDonald