An interesting read
See: "Tranformation Optics and Subwavelength Control of Light", J. B. Pendry, A. Aurby, D. R. Smith, S. A. Maier; Science, volume 337 pages 549 to 552, 3 August 2012 www.sciencemag.org
"Our intuitive understand of light has it foundations in the ray approximation and is intimately connected with our vision. As far as our eyes are concerned, light behaves like a steam of particles. We look inside the wavelength and study the properties of plasmoic structures with dimensions of just a few nanometers, where at a tenth or even a hundredth of the wavelength of visible light the ray picture fails. We review the concept of transformation optics that manipulates electric and magnetic field lines, rather than rays; can provide an equally intuitive understanding of subwavelength phenomena; and at the same time can be an exact discription at the leverl of Maxwell's equations"