Implementation of a superresolution far-field spot-generator with 1/5 the diffraction limit

Diffractive optical elements with point spread functions that exhibit diameters smaller than the wavelength-dependent diffraction limit are considered superresolution filters. A superresolving spot generator with a center-lobe of 1/5th the diameter of the diffraction-limited Airy function was designed using the theory of super-oscillations. The fundamental aspects of the design algorithm, the fabrication process, as well as the experimental verification of the diffraction pattern are described in detail.