High-Resolution Phase Reconstruction in Ground-based Astronomy

Raymond Chan (City U of Hong Kong)

Mar 18. 2021, 13:00 — 13:45

Adaptive optics is a commonly used technique to correct the phase distortions caused by the Earth's atmosphere to improve the image quality of the ground-based imaging systems. However, the observed images still suffer from the blur caused by the adaptive optics residual wavefront. We propose a model for reconstructing the residual phase in high-resolution from a sequence of low-resolution deformable mirror data. Our model is based on the turbulence statistics and the Taylor frozen flow hypothesis. A tomography problem for the phase distortions from different altitudes is solved to get a high-quality phase reconstruction. The associated joint optimization problem was solved by an alternating minimization method which results in a high-resolution reconstruction algorithm with adaptive wind velocities. Numerical simulations are carried out to show the effectiveness of our approach.

Joint work with Rihuan Ke (University of Cambridge), Roland Wagner (RICAM), and Ronny Ramlau (RICAM).

Further Information
Venue:
Erwin Schrödinger Institute - virtual
Associated Event:
Tomographic Reconstructions and their Startling Applications (Online Workshop)
Organizer(s):
Wolfgang Drexler (Med U Vienna)
Peter Elbau (U of Vienna)
Ronny Ramlau (RICAM, Linz)
Monika Ritsch-Marte (Med Uni Innsbruck)
Otmar Scherzer (U of Vienna)
Gerhard Schütz (TU Vienna)