Super-resolution of active spatial frequency heterodyning using holographic approach

This paper describes a technique of super-resolution that is based on holographic imaging in which three holograms corresponding to one orientation of the fringes are recorded. To recover the two-dimensional object spatial frequency, we take four orientations of the fringes with 45 degrees steps. For each orientation of the fringes, the hologram recording scheme will remain the same. The orientation of the reference beam is fixed throughout the measurements. Once the three holograms are recorded for each orientation of the fringes with a fixed amplitude of the reference beam, an algorithm is applied for each orientation. The algorithm processes the three holograms to construct a synthesized spectrum in a particular orientation; taking the inverse Fourier transform of this synthesized spectrum will give the synthesized image in that particular orientation. Different synthesized spectra are combined to obtain an overall synthesized spectrum and a super-resolved image is formed.