Monday, May 16, 2011

US Patent 7940477 - Solid immersion lens with nanowire focusing

In order to increase the physical resolution limit of optical microscopes one technique is to immerse the optics in a high index refractive liquid to increase the maximum numerical aperture. This patent teaches an additional technique in which a nanowire structure is used at the optical focal point to generate near field effects. Claim 1 reads:

1. A solid immersion lens for optical applications,

which comprises a spherical sector bounded by a plane surface,

wherein a wire or tube of cylindrical shape made of a semiconductor material, the generatrices of which are perpendicular to the plane surface and at least one dimension of which is of nanoscale, is placed on the plane surface at the focal point of said solid immersion lens.