From Nature
http://www.nature.com/doifinder/10.1038/447266a"At the heart of the hyperlens concept4, 5 lies a nanostructured ‘metamaterial’ whose dielectric constant — a measure of a material’s response to the electric field of the incident light — has opposite signs in two orthogonal directions. The effect of this anisotropy is to do away with the lower limit on the wavelength of a propagating field that is characteristic of a conventional, isotropic medium. With no lower limit on the propagating light’s wavelength, there is no diffraction limit — and so, theoretically, unbounded image resolution.
As soon as waves of very small wavelength emerge from this ‘optical hyperspace’ into air, however, they can no longer propagate, and again become evanescent. To deliver the sub-wavelength information carried by such waves into the far field, one must first increase their wavelength to the point when propagation in air is possible. The cylinder (or half-cylinder) geometry of the hyperlens is specifically designed to achieve this, by slowly increasing the wavelength as the field spreads away from the centre of the device (Fig. 1).
In their experimental realizations of the hyperlens, Liu et al.1, of the University of California, Berkeley, and Smolyaninov et al.2, of the University of Maryland, Baltimore, use a half-cylinder1 and a cylinder2 of layered metamaterials whose dielectric constant is strongly isotropic in the radial and tangential directions. The objects to be imaged are placed in the hollow middle and illuminated from the outside — in Smolyaninov and colleagues’ case, from the top of the cylinder, and for Liu and colleagues from the side of the half-cylinder."
I haven't had to read scientific papers since I graduated from college in the mid 90s--it's hard to see that writing style never makes it big with a general audience! :silly:
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