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arXiv · 0711.1219

Adaptive Speckle Imaging Interferometry: a new technique for the analysis of microstructure dynamics, drying processes and coating formation

Laurent Brunel·Alice Brun·Patrik Snabre·Luca Cipelletti
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Abstract

We describe an extension of multi-speckle diffusing wave spectroscopy adapted to follow the non-stationary microscopic dynamics in drying films and coatings in a very reactive way and with a high dynamic range. We call this technique "Adaptive Speckle Imaging Interferometry". We introduce an efficient tool, the inter-image distance, to evaluate the speckle dynamics, and the concept of "speckle rate" (SR, in Hz) to quantify this dynamics. The adaptive algorithm plots a simple kinetics, the time evolution of the SR, providing a non-invasive characterization of drying phenomena. A new commercial instrument, called HORUS(R), based on ASII and specialized in the analysis of film formation and drying processes is presented.

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Laurent Brunel, Alice Brun, Patrik Snabre, Luca Cipelletti. 2007-11-08. Adaptive Speckle Imaging Interferometry: a new technique for the analysis of microstructure dynamics, drying processes and coating formation. https://doi.org/10.1364/oe.15.015250

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