General Dynamics Corporation, Electronics Division

Thomas W Kornbau

Robert A Sievers

A method of forming metallic patterns on a dielectric surface such as a radome surface that has a compound curve which includes the steps of coating the radome with a metal and then with a photoresist. An electrical pattern is formed on the photographic emulsion of a thin membrane that is used as a photo mask. A water soluble adhesive, which is non degradable to the exposure and development of the photoresist and the etching of the conductive surface is applied to the metallic surface and the photo mask is pressed into position on the adhesive to conform to the curvature of the radome. The photo mask is removed and the electrical pattern is provided on the surface by conventional developing and etching techniques to provide a clear, well defined pattern even in arrays wherein the pattern segments are of small dimension.

Method of forming metallic patterns on curved surfaces

An angle filter for electromagnetic radiation having a predetermined wavelength .lambda.. The angle filter includes a planar-parallel pair of perforated conductive plates having arrays of periodic perforations. The perforations are spaced apart for creating grating lobes between the plates at the predetermined wavelength .lambda. at incidence angles greater than .theta..sub.G. All of the perforations in both plates are identical. The spacing between the perforations in both plates is identical. The plates are staggered so that the perforations in at least one dimension of one plate are aligned between the perforations in the corresponding dimension of the other plate for minimizing coupling between the plates at incidence angles somewhat greater than .theta..sub.G in a plane corresponding to the one dimension. The center-to-center spacing between perforations in the one dimension is equal to .lambda. divided by 2 sin .theta., wherein .theta. is an incidence angle greater than .theta..sub.G. In an embodiment in which the plates contain the periodic perforations in two normal dimension, which define E and H-planes, the plates are staggered so that the perforations in both dimensions of one plate are aligned between the perforations in the corresponding dimensions of the other plate for minimizing coupling between the plates over a range of incidence angles in both the E and H-planes.

Growing community of inventors

Poway, CA, United States of America

Thomas W Kornbau