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Coherent imaging of a pure phase object with classical incoherent light

M. Bache·D. Magatti·A. Gatti·E. Brambilla·F. Ferri·L. A. Lugiato
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Abstract

By using the ghost imaging technique, we experimentally demonstrate the reconstruction of the diffraction pattern of a {\em pure phase} object by using the classical correlation of incoherent thermal light split on a beam splitter. The results once again underline that entanglement is not a necessary feature of ghost imaging. The light we use is spatially highly incoherent with respect to the object ($\approx 2 μ$m speckle size) and is produced by a pseudo-thermal source relying on the principle of near-field scattering. We show that in these conditions no information on the phase object can be retrieved by only measuring the light that passed through it, neither in a direct measurement nor in a Hanbury Brown-Twiss (HBT) scheme. In general, we show a remarkable complementarity between ghost imaging and the HBT scheme when dealing with a phase object.

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M. Bache, D. Magatti, A. Gatti, E. Brambilla, F. Ferri, L. A. Lugiato. 2006-07-06. Coherent imaging of a pure phase object with classical incoherent light. https://doi.org/10.1103/physreva.73.053802

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