In plane focus

Imaging systems, electronics and digital computers could benefit from a new generation of ‘near-perfect’ lenses, predicted by engineers at the University of Edinburgh and Pennsylvania State University.

Such lenses have been the subject of much research over the past decade, but have depended on expensive and complex devices. But Tom Mackay of Edinburgh and Akhlesh Lakhtakia of Penn State say the same properties could be obtainable with cheap materials and simple production processes.

Lenses and their properties, plus their drawbacks, have been known for centuries — the effectiveness of the lens depends on how well you can grind it. The theory of perfect lenses goes back to 1904, said Lakhtakia, and depends on how materials transmit the electrical and magnetic components of electrical and magnetic energy. This depends on properties called the dielectric and magnetic permittivity and, in theory, a material showing a certain combination of these properties will allow materials to refract light in the opposite direction from that seen with normal materials.