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arXiv · 1212.5040

Digital in-line holography in thick optical systems: application to visualization in pipes

Nicolas Verrier·Coëtmellec Sébastien·Brunel Marc·Lebrun Denis
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Abstract

In this paper we apply digital in-line holography to image opaque objects through a thick plano-concave pipe. Opaque fibers and opaque particles are considered}. Analytical expression of the intensity distribution in the CCD sensor plane is derived using generalized Fresnel transform. \textbf{The proposed model has the ability to deal with various pipe shape and thickness and compensates for the lack of versatility of classical DIH models. Holograms obtained with a 12 mm thick plano-concave pipe are then reconstructed using fractional Fourier transform (FRFT).} This method allows us to get rid of astigmatism. Numerical and experimental results are presented.

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Nicolas Verrier, Coëtmellec Sébastien, Brunel Marc, Lebrun Denis. 2012-12-20. Digital in-line holography in thick optical systems: application to visualization in pipes. https://doi.org/10.1364/ao.47.004147

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