Calibration of a deformable mirror and Strehl ratio measurements by use of phase diversity.
Calibration experiments with a bimorph mirror are presented. Phase-diversity wave-front sensing is used for measuring the control matrix, nulling wave-front errors in the optical setup, including the mirror, and measuring Strehl ratios and residual higher-order aberrations. The Strehl ratio of the calibrated system is measured to be 0.975, corresponding to 1/40 wave rms in the residual wave front. The conclusion is that a phase-diversity wave-front sensor is easier to install and use than interferometers and can replace them in optical setups for testing adaptive optics systems.
Löfdahl
M G
MG
Royal Swedish Academy of Sciences, Stockholm Observatory, SE-133 36 Saltsjöbaden, Sweden. mats@astro.su.se
Scharmer
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GB
Wei
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