A Systematic Approach for the design of Metallic Delay Lenses

A major disadvantage of natural dielectric lenses is the excessive physical weight of the dielectric material. Artificial dielectric lenses are proposed to replace the actual dielectric and overcome this disadvantage. In this paper, we introduce a systematic and comprehensive method for the design of metallic delay lenses. Previous approaches suggest analytical formulas based on effective medium theories for the evaluation of the effective electromagnetic properties of artificial dielectrics. The method presented in this paper goes beyond the applicability of the theoretical methods, since it is applicable for periodic structures with larger metallic elements that are desired in practice. To validate this method, a metallic delay lens comprising of copper spheres is used as a proof of concept demonstrator and favorably compared with the solid lenses.