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Ultra-Thin Floating Mirrors

Ermanno F. Borra·Anna Ritcey·Etienne Artigau
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Abstract

We discuss a new technology that promises large inexpensive mirrors. We argue that it should be possible to tilt a rotating viscous liquid by perhaps as much as a few tens of degrees. The tilted liquid parabolic surface is used as the support for a thin reflecting metallic film. We demonstrate two critical steps: that a viscous liquid mirror can be tilted and that an optical quality metallic film can be deposited on a liquid. The advent of astronomically useful tilted floating mirror telescopes is contingent on the development of high-viscosity high-reflectivity liquids. It is a good omen that we already have identified two classes of such liquids; however there remain technical challenges to overcome before such liquids can be used in viable telescopes.

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Ermanno F. Borra, Anna Ritcey, Etienne Artigau. 1999-01-19. Ultra-Thin Floating Mirrors. https://arxiv.org/abs/astro-ph/9901255

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