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Ghost imaging schemes: fast and broadband

M. Bache·E. Brambilla·A. Gatti·L. A. Lugiato
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Abstract

In ghost imaging schemes information about an object is extracted by measuring the correlation between a beam that passed the object and a reference beam. We present a spatial averaging technique that substantially improves the imaging bandwidth of such schemes, which implies that information about high-frequency Fourier components can be observed in the reconstructed diffraction pattern. In the many-photon regime the averaging can be done in parallel and we show that this leads to a much faster convergence of the correlations. We also consider the reconstruction of the object image, and discuss the differences between a pixel-like detector and a bucket detector in the object arm. Finally, it is shown how to non-locally make spatial filtering of a reconstructed image. The results are presented using entangled beams created by parametric down-conversion, but they are general and can be extended also to the important case of using classically correlated thermal-like beams.

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M. Bache, E. Brambilla, A. Gatti, L. A. Lugiato. 2004-12-07. Ghost imaging schemes: fast and broadband. https://doi.org/10.1364/opex.12.006067

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