Phase contrast techniques for wavefront sensing and calibration in adaptive optics

Eric E. Bloemhof, J. Kent Wallace, Robert K. Tyson, Michael Lloyd-Hart
2003 Astronomical Adaptive Optics Systems and Applications  
The wavefront sensor is the most critical component of an adaptive optics (AO) system. Most astronomical systems use one of a small number of alternatives, notably the Shack-Hartmann or the curvature sensor; these are sensitive to the first and second derivative of the wavefront phase, respectively. In this paper, we explore a novel adaptation of the phase-contrast techmque developed for microscopy by Zemke to measure phase directly, and show that it is potentially useful in astronomical
more » ... e optics, both for closed-loop wavefront sensing and for off-line calibration of the system PSF. The phase-contrast WFS should enjoy an advantage in lower read noise, as well as a natural match to the pistontype deformable mirror actuators commonly in use with most current Shack-Hartmann systems, and favorable error propagation during wavefront reconstruction. It appears that it might be possible to implement versions with the reasonably broad spectral bandwidth desired for astronomical applications, and to integrate them with relatively minor modifications to existing A 0 system architectures.
doi:10.1117/12.507245 fatcat:mcavoh6urfcoxmlpp64aw2r744