Dielectric lens and electromagnetic device with same

A dielectric lens, includes: a three-dimensional, 3D, body of dielectric material having a spatially varying dielectric constant, Dk; the 3D body having at least three regions R(i) with local maxima of dielectric constant values Dk(i) relative to surrounding regions of respective ones of the at least three regions R(i), locations of the at least three regions R(i) being defined by local coordinates of: azimuth angle(i), zenith angle(i), and radial distance(i), relative to a particular common point of origin associated with the 3D body, where (i) is an index that ranges from 1 to at least 3; wherein the spatially varying Dk of the 3D body is configured to vary as a function of the zenith angle between a first region R(1) and a second region R(2) at a given azimuth angle and a given radial distance.