A fresnel lens designed using a perforated dielectric

A phase-compensating Fresnel lens was designed and fabricated using a flat perforated dielectric material. The perforations in the dielectric material were designed to create the zones of different dielectric constants needed to obtain proper phase compensation for the Fresnel lens. A prototype lens designed to operate at 30 GHz was fabricated, consisting of zones with four different synthesized values of dielectric constant. The lens, designed with a diameter of 15 cm, had a peak gain of 28 dB, with a 1 dB gain bandwidth of 14%.