TY - JOUR
T1 - Characterizing deformable mirrors for the MagAO-X instrument
AU - Van Gorkom, Kyle
AU - Males, Jared R.
AU - Close, Laird M.
AU - Lumbres, Jennifer
AU - Hedglen, Alex
AU - Long, Joseph D.
AU - Haffert, Sebastiaan Y.
AU - Guyon, Olivier
AU - Kautz, Maggie
AU - Schatz, Lauren
AU - Miller, Kelsey
AU - Rodack, Alexander T.
AU - Knight, Justin M.
AU - Morzinski, Katie M.
N1 - Funding Information:
We are grateful for the support of NSF MRI Award #1625441 Development of a Visible Wavelength Extreme Adaptive Optics Coronagraphic Imager for the 6.5 meter Magellan Telescope. The authors have no conflicts of interest to declare.
Publisher Copyright:
© 2021 Society of Photo-Optical Instrumentation Engineers (SPIE).
PY - 2021/7/1
Y1 - 2021/7/1
N2 - The MagAO-X instrument is an extreme adaptive optics system for high-contrast imaging at visible- and near-infrared wavelengths on the Magellan Clay Telescope. A central component of this system is a 2040-actuator microelectromechanical deformable mirror (DM) from Boston Micromachines Corp. that operates at 3.63 kHz for high-order wavefront control (the tweeter). Two additional DMs from ALPAO perform the low-order (the woofer) and non-common-path science-arm wavefront correction (the NCPC DM). Prior to integration with the instrument, we characterized these devices using a Zygo Verifire Interferometer to measure each DM surface. We present the results of the characterization effort here, demonstrating the ability to drive the tweeter to a flat of 6.9 nm root-mean-square (RMS) surface (and 0.56 nm RMS surface within its control bandwidth), the woofer to 2.2-nm RMS surface, and the NCPC DM to 2.1-nm RMS surface over the MagAO-X beam footprint on each device. Using focus-diversity phase retrieval on the MagAO-X science cameras to estimate the internal instrument wavefront error, we further show that the integrated DMs correct the instrument WFE to 18.7 nm RMS, which, combined with a 11.7% pupil amplitude RMS, produces a Strehl ratio of 0.94 at Hα.
AB - The MagAO-X instrument is an extreme adaptive optics system for high-contrast imaging at visible- and near-infrared wavelengths on the Magellan Clay Telescope. A central component of this system is a 2040-actuator microelectromechanical deformable mirror (DM) from Boston Micromachines Corp. that operates at 3.63 kHz for high-order wavefront control (the tweeter). Two additional DMs from ALPAO perform the low-order (the woofer) and non-common-path science-arm wavefront correction (the NCPC DM). Prior to integration with the instrument, we characterized these devices using a Zygo Verifire Interferometer to measure each DM surface. We present the results of the characterization effort here, demonstrating the ability to drive the tweeter to a flat of 6.9 nm root-mean-square (RMS) surface (and 0.56 nm RMS surface within its control bandwidth), the woofer to 2.2-nm RMS surface, and the NCPC DM to 2.1-nm RMS surface over the MagAO-X beam footprint on each device. Using focus-diversity phase retrieval on the MagAO-X science cameras to estimate the internal instrument wavefront error, we further show that the integrated DMs correct the instrument WFE to 18.7 nm RMS, which, combined with a 11.7% pupil amplitude RMS, produces a Strehl ratio of 0.94 at Hα.
KW - adaptive optics
KW - deformable mirrors
KW - high-contrast imaging
KW - phase retrieval
KW - wavefront control
UR - https://www.scopus.com/pages/publications/85116311737
UR - https://www.scopus.com/pages/publications/85116311737#tab=citedBy
U2 - 10.1117/1.JATIS.7.3.039001
DO - 10.1117/1.JATIS.7.3.039001
M3 - Article
AN - SCOPUS:85116311737
SN - 2329-4124
VL - 7
JO - Journal of Astronomical Telescopes, Instruments, and Systems
JF - Journal of Astronomical Telescopes, Instruments, and Systems
IS - 3
M1 - 039001
ER -