Aperture synthesis in phase retrieval using a volume-speckle field

Universität Stuttgart, Stuttgart, Baden-Württemberg, Germany
Optics Letters (Impact Factor: 3.29). 05/2007; 32(7):733-5. DOI: 10.1364/OL.32.000733
Source: PubMed


The resolution of the reconstructed wave by a phase-retrieval method using a volume-speckle field depends on the aperture defined by the size of the CCD array. The use of a larger aperture is introduced by measuring the speckle field at two different positions in the transverse plane and stitching the measurements together. Improvements in the quality of reconstructions are demonstrated experimentally and by computer simulations. Undesirable effects of camera tilt on the quality of reconstructions from synthetic aperture intensity measurements are experimentally observed and corrected.

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    • "Instead of the regular diffraction patterns used in [14], speckle intensity measurements were input into the iterative phase retrieval algorithm [15]. Sub-pixel scanning [15] to enhance the speckle measurements and aperture synthesis [16] to increase the effective numerical aperture, were also demonstrated. The multiple intensity approach [14] [15] has also been adapted to reconstruct smooth or low-curvature wavefronts. "
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