Near-field focusing and magnification through self-assembled nanoscale spherical lenses

Nanolenses beat the barrier The performance of a light microscope is intrinsically constrained by the Abbe diffraction limit. No matter how close to optical perfection it is, an imaging system cannot resolve two objects that are beyond this natural limit, which is dependent on the wavelength of the observed light and its angular distribution. Several methods have been devised to beat the diffraction limit, but these have generally required esoteric excitation schemes, so remain impractical. Lee et al. are working on a new way of beating the limit, using nanoscale spherical lenses that self-assemble by bottom-up integration of cup-shaped organic molecules called calixarenes. Lenses produced in this way have very short focal lengths that can generate near-field magnification beyond the diffraction limit, enabling the resolution of features of the order of 200 nm. The lenses can be placed at will on a surface and, among other things, can be used to reduce the size of deep-ultraviolet lithography features.