Scanning holographic microscopy with resolution exceeding the Rayleigh limit of the objective by superposition of off-axis holograms.

Department of Physics, Virginia Tech, Blacksburg, Virginia 24061-0435, USA.
Applied Optics (Impact Factor: 1.69). 03/2007; 46(6):993-1000. DOI: 10.1364/AO.46.000993
Source: PubMed

ABSTRACT We present what we believe to be a new application of scanning holographic microscopy to superresolution. Spatial resolution exceeding the Rayleigh limit of the objective is obtained by digital coherent addition of the reconstructions of several off-axis Fresnel holograms. Superresolution by holographic superposition and synthetic aperture has a long history, which is briefly reviewed. The method is demonstrated experimentally by combining three off-axis holograms of fluorescent beads showing a transverse resolution gain of nearly a factor of 2.

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