Phase retrieval techniques are utilized to correct low order wavefront aberrations originating from misalignments of the optical system in space based telescope concepts. Traditional phase retrieval involves observation of the Point Spread Function (PSF) and a diversity measurement, usually focus diversity although other measures are possible, to reconstruct the incident wavefront at the science detector. We consider a Machine Learning model trained originally on simulated data, and then augmented with real focus diversity data from the Tiny Observatory for Telescope Optimization (TOTO) testbed at the University of Arizona. We then compare the wavefront sensing performance of the Machine Learning model with known truth values of the generated dataset. The model predictions for low order Zernikes on TOTO data after training and validation show a reasonable agreement with the true Zernike coefficients.
By combining a physical optics model with a flexible machine learning model, this work can avoid introducing unphysical features in the resulting PSF estimate and explores the temporal coherence of structures in telemetry and the limitations of learning this relationship from data sampled on such different timescales.
Joseph D. Long, S. Haffert, J. Males et al.· Astronomical Telescopes + In...· 1 citation
Wavefront sensing is an integral part of all adaptive optics systems as it allows for the phase of the incoming light to be measured and corrected. In strong scintillation conditions, such as during daytime, or horizontal propagation, traditional, slope-based wavefront sensing techniques have a large decrease in perfor...
IMACT (Image-based Mirror Phasing and Alignment using Convolutional neTworks) measures point spread functions (PSFs) on a secondary mirror detector separated from the main science camera by applying a deep machine learning algorithm.
Daniel Martin, Andrew P. Reeves, Cyril Bourgenot et al.· Aerospace· 0 citations
Efficient operation of a large optical telescope requires the telescope, the active optics, and the adaptive optics to begin each acquisition close to their physically correct state in order to reduce setup time. At the Large Binocular Telescope (LBT), the acquisition sequence must place the guide star on the active-op...
J. C. Guerra, S. Ragland, B. Mechtley· Astronomical Telescopes + In...· 0 citations
Atmospheric turbulence severely degrades the imaging performance of ground-based solar telescopes, while wavefront sensing for extended solar targets remains challenging because target structures are strongly entangled with turbulence-induced aberrations. To address this problem, this work establishes a robust, target-...
Xin-Lan Ge, Ao Li, Li-Cheng Zhu et al.· Astrophysical Journal Supple...· 0 citations
We use cookies to run the site and, with your consent, for analytics and to show ads.
See our Cookie Policy.
