Imaging the near field

In an earlier paper we introduced the concept of the perfect lens which focuses both near and far electromagnetic fields, hence attaining perfect resolution. Here we consider refinements of the original prescription designed to overcome the limitations of imperfect materials. In particular we show that a multilayer stack of positive- and negative-refractive-index media is less sensitive to imperfections. It has the novel property of behaving like a fibre-optic bundle but one that acts on the near field, and not just the radiative component. The effects of retardation are included and minimized by making the slabs thinner. Absorption then dominates image resolution in the near field. The deleterious effects of absorption in the metal are reduced for thinner layers.