Research on an artificial dielectric material for millimeter-wave imaging application

Material made of artificial molecules fabricated from cage-shaped granules of conductor (CGC) is introduced and its electrical and magnetic characteristics are presented. Its refractive index, calculated using complex relative permittivity and complex relative permeability, is 1.504 at 35 GHz. A two-element lens, consisting of a pair of spherical plano-convex lenses, was designed and fabricated by embedding CGC in poly(methyl methacrylate). The active millimeter-wave imaging system was constructed with the two-element lens by having the curved surfaces face each other. Millimeter-wave (MMW) images of a right trapezoid and twin bars were obtained. The image quality was acceptable, proving that the CGC material has the ability to refract MMWs in MMW imaging and that the ability contrasts with that of some traditional high polymer material.