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arXiv · 1807.04370

Characterization of deformable mirrors for the MagAO-X project

Kyle Van Gorkom·Kelsey L. Miller·Jared R. Males·Olivier Guyon·Alexander T. Rodack·Jennifer Lumbres·Justin M. Knight
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Abstract

The MagAO-X instrument is an upgrade of the Magellan AO system that will introduce extreme adaptive optics capabilities for high-contrast imaging at visible and near-infrared wavelengths. A central component of this system is a 2040-actuator microelectromechanical (MEMS) deformable mirror (DM) from Boston Micromachines Corp. (BMC) that will operate at 3.63 kHz for high-order wavefront control. Two additional DMs from ALPAO will perform low-order and non-common-path science-arm wavefront correction. The accuracy of the wavefront correction is limited by our ability to command these DMs to a desired shape, which requires a careful characterization of each DM surface. We have developed a characterization pipeline that uses a Zygo Verifire Interferometer to measure the surface response and a Karhunen-Lo\`eve transform to remove noise from our measurements. We present our progress in the characterization process and the results of our pipeline applied to an ALPAO DM97 and a BMC Kilo-DM, demonstrating the ability to drive the DMs to a flat of $\lesssim$ 2nm and $\lesssim$ 4nm RMS in our beam footprint on the University of Arizona Wavefront Control (UAWFC) testbed.

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Kyle Van Gorkom, Kelsey L. Miller, Jared R. Males, Olivier Guyon, Alexander T. Rodack, Jennifer Lumbres, Justin M. Knight. 2018-07-11. Characterization of deformable mirrors for the MagAO-X project. https://arxiv.org/abs/1807.04370

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