A Digital Prism Wavefront Sensor for Ground-Based Astronomical Image Correction

The pyramid wavefront sensor is used in astronomical imaging systems to estimate the wavefront induced by the time-varying atmosphere. We have demonstrated that a spatial light modulator can be used to digitally generate a prism (pyramid) WFS and for the first time, we have created the digital 3-sided and digital cone wavefront sensors (WFS). The digital prism WFS is built in the University of Canterbury Electrical and Computer Engineering Optics lab. The 3-sided and cone WFS are first designed in simulation and then converted to a format suitable for the digital WFS. We show the resulting WFS images captured for the digitally generated WFS agree well with the simulated images for a planar and defocused wavefront. We have shown that using a spatial light modulator it is feasible to implement a digital 3-sided and cone WFS.

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