The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 19, 1980
Filed:
Aug. 25, 1978
Leland H Hemming, Poway, CA (US);
Plessey, Incorporated, New York, NY (US);
Abstract
Various aspects of electro-magnetic testing are facilitated by inserting a foamed plastic dielectric lens at a particular position between a particular radiating source and the test aperture. The lens is constructed according to electro-optic formulae and the radiation wavelength to produce a plane wave of uniform phase. To control extraneous energy contributed by reflections from the flat face of the lens, this surface is provided with two layers of high-performance absorber material. The amplitude characteristics in the test region are controlled by appropriate selection of the source antenna. Radiation-absorbent material is also provided to eliminate amplitude distortion. This makes possible testing under far-field conditions in test cells of modest size, which has heretofore been possible only with elaborate parabolic reflectors. Weather restrictions on use of free-space ranges, the sheer size of such ranges, and security problems attendant on their use, are all thus avoided. The lens can be manufactured from any plastic having a suitable dielectric constant, by either blowing the plastic in a suitable mold, or by machining from a preformed foam block. The absorber layers are loaded with conductive carbon to provide desired insertion loss and attached to the flat face.