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arXiv · 1704.08766

Z-scan confocal method for indirect focusing location

P. Castro-Marín·G. Castro-Olvera·C. Ruíz·J. Garduño-Mejía·M. Rosete-Aguilar·N. C. Bruce
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Abstract

We present a new technique that we have defined as the z-scan confocal method to determine the absolute location and size of the focal spot in a tight focused ultrashort laser pulse. The method permits to accurately position a target in the focal spot with a fast response. The technique is designed to help to automatize the location of an overdense target in focus in a laser plasma experiment. The method allows for a fast localization of the focal position and the relative motion of the target with respect to it. As an example of the capacities we measure the defocusing of a fast rotating disc in several radius to reconstruct the motion of the disc at focus.

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P. Castro-Marín, G. Castro-Olvera, C. Ruíz, J. Garduño-Mejía, M. Rosete-Aguilar, N. C. Bruce. 2017-04-26. Z-scan confocal method for indirect focusing location. https://arxiv.org/abs/1704.08766

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