Theory of a reflection grating with narrow grooves

Abstract

The scattering of a plane H-polarized wave from a grating composed of narrow grooves in a perfectly conducting surface is investigated theoretically using conformal transformation techniques. The theory is exact in the limit a/d --• 0, where a is the slot width and d is the grating period, and remains valid for practical values of a/d. A necessary condition is derived for the elimination of the specularly reflected wave. When only the -1 and 0 order space waves are present, this condition becomes just the well-known Bragg condition. Phys., 9, 1509-1515. Tseng, D. Y. (1967), Guiding and scattering of electromagnetic fields by corrugated surfaces, Ph.D. thesis, Polytechnic Instit. of Brooklyn, New York. Tseng, D. Y., A. Hessel, and A. A. Oliner (1969), Scattering by a multimode corrugated structure with application to P-type Wood anomalies, Alta Freq., 38, 82-88. Verbitskiy, I. L. (1976), The diffraction of a plane wave by dense comb, Radio Eng. Electron. Phys., 21, 41-46.