Boundary conditions for field distribution in the aperture plane and their effect on diffraction patterns

Abstract

This study shows the effect of different assumptions of the field in the aperture plane on diffraction patterns. The assumptions include (1) Kirchhoff's black screen, (2) screen with finite conductivity, (3) screen with reflection at the edges of the aperture and (4) screen with combined effects as described in (2) and (3). It is shown numerically and experimentally that change of the description for boundary conditions without change aperture dimensions and the wavelength of incident radiation does not affect the results noticeably if diffraction fields are observed not too close to the aperture.