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arXiv · 1402.1743

Sub-nanometer flattening of a 45-cm long, 45-actuator x-ray deformable mirror

L. A. Poyneer·T. McCarville·T. Pardini·D. Palmer·A. Brooks·M. J. Pivovaroff·B. Macintosh
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Abstract

We have built a 45-cm long x-ray deformable mirror of super-polished single-crystal silicon that has 45 actuators along the tangential axis. After assembly the surface height error was 19 nm rms. With use of high-precision visible-light metrology and precise control algorithms, we have actuated the x-ray deformable mirror and flattened its entire surface to 0.7 nm rms controllable figure error. This is, to our knowledge, the first sub-nanometer active flattening of a substrate longer than 15 cm.

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L. A. Poyneer, T. McCarville, T. Pardini, D. Palmer, A. Brooks, M. J. Pivovaroff, B. Macintosh. 2014-02-07. Sub-nanometer flattening of a 45-cm long, 45-actuator x-ray deformable mirror. https://doi.org/10.1364/ao.53.003404

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