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arXiv · 1805.12036

Theoretical compensation of static deformations of freeform multi mirror substrates

Johannes Hartung·Henrik von Lukowicz·Jan Kinast
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Abstract

Varying temperatures influence the figure errors of freeform metal mirrors by thermal expansion. Furthermore, different materials lead to thermo-elastic bending effects. The article presents a derivation of a compensation approach for general static loads. Utilizing perturbation theory this approach works for shape compensation of substrates which operate in various temperature environments. Verification is made using a finite element analysis which is further used to produce manufacturable CAD models. The remaining low spatial frequency errors are deterministically correctable using diamond turning or polishing techniques.

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Johannes Hartung, Henrik von Lukowicz, Jan Kinast. 2018-05-30. Theoretical compensation of static deformations of freeform multi mirror substrates. https://doi.org/10.1364/ao.57.004020

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