The impact of curvature on surface current near the rounded corners of a scatterer.

When a perfectly electrically conducting two-dimensional scatterer, which is smooth except at finitely many sharp corner points, is illuminated by an E-polarised electromagnetic plane wave, the surface current density exhibits singularities at those corner points, whilst in the H-polarised case the surface density exhibits singularities in its derivative at those points. Once the corners are rounded, the surface density becomes non-singular. It is of interest to examine the impact of this rounding upon the surface current and other observed physical quantities such as the far-field, as the rounding becomes more pronounced.