Electromagnetic Scattering by Thin Conducting Plates at Glancing Incidence

The signal scattered back from rectangular and triangular plates illuminated edge-on in an electromagnetic field is found to be large when the incident magnetic vector is normal to the plates. Explanations are sought in terms of edge diffraction, and experimental measurements indicate that the currents in the plates are predominant near to edges. The extension of rigorous theoretical results on infinite edges to the derivation of currents in finite edges is discussed; and it is shown what type of modification appears necessary to account for the experimental observations. A method of testing a hypothetical current distribution for the boundary conditions is propounded.