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arXiv · 1506.06370

Sun-tracking optical element realized using thermally activated transparency-switching material

Harry Apostoleris·Marco Stefancich·Samuele Lilliu·Matteo Chiesa
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Abstract

We present a proof of concept demonstration of a novel optical element: a light-responsive aperture that can track a moving light beam. The element is created using a thermally-activated transparency-switching material composed of paraffin wax and polydimethylsiloxane (PDMS). Illumination of the material with a focused beam causes the formation of a localized transparency at the focal spot location, due to local heating caused by absorption of a portion of the incident light. An application is proposed in a new design for a self-tracking solar collector.

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Harry Apostoleris, Marco Stefancich, Samuele Lilliu, Matteo Chiesa. 2015-06-21. Sun-tracking optical element realized using thermally activated transparency-switching material. https://doi.org/10.1364/oe.23.00a930

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