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arXiv · 1705.03993

Incoherent lensless imaging via coherency back-propagation

Ahmed El-Halawany·Andre Beckus·H. Esat Kondakci·Morgan Monroe·Nafiseh Mohammadian·George K. Atia·Ayman F. Abouraddy
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Abstract

The two-point complex coherence function constitutes a complete representation for scalar quasi-monochromatic optical fields. Exploiting dynamically reconfigurable slits implemented with a digital micromirror device, we report on measurements of the complex two-point coherence function for partially coherent light scattering from a `scene' comprising one or two objects at different transverse and axial positions with respect to the source. Although the intensity shows no discernible shadows in absence of a lens, numerically back-propagating the measured complex coherence function allows estimating the objects' sizes and locations -- and thus the reconstruction of the scene.

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Ahmed El-Halawany, Andre Beckus, H. Esat Kondakci, Morgan Monroe, Nafiseh Mohammadian, George K. Atia, Ayman F. Abouraddy. 2017-05-11. Incoherent lensless imaging via coherency back-propagation. https://doi.org/10.1364/ol.42.003089

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