Performance limits of adaptive-optics/high-contrast imagers with pyramid wave-front sensors

Abstract

Advanced AO systems will likely utilise Pyramid wave-front sensors (PWFS) over the traditional Shack-Hartmann sensor in the quest for increased sensitivity, peak performance and ultimate contrast. Here, we wish to bring knowledge and quantify the PWFS theoretical limits as a means to highlight its properties and use cases. We explore forward models for the PWFS in the spatial-frequency domain for they prove quite useful since a) they emanate directly from physical-optics (Fourier) diffraction theory; b) provide a straightforward path to meaningful error breakdowns, c) allow for reconstruction algorithms with $O(nlog(n))$ complexity for large-scale systems and d) tie in seamlessly with decoupled (distributed) optimal predictive dynamic control for performance and contrast optimisation. All these aspects are dealt with here. We focus on recent analytical PWFS developments and demonstrate the performance using both analytic and end-to-end simulations. We anchor our estimates with observed on-sky contrast on existing systems and then show very good agreement between analytical and Monte-Carlo estimates for the PWFS. For a potential upgrade of existing high-contrast imagers on 10\,m-class telescopes with visible or near-infrared PWFS, we show under median conditions at Paranal a contrast improvement (limited by chromatic and scintillation effects) of 2x-5x by replacing the wave-front sensor alone at large separations close to the AO control radius where aliasing dominates, and factors in excess of 10x by coupling distributed control with the PWFS over most of the AO control region, from small separations starting with the Inner Working Angle of typically 1-2 $\lambda /D$ to the AO correction edge (here 20 $\lambda /D$).

arXiv comment12 pages, 13 figures

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Cited by in corpus (12)

• Closed Loop Predictive Control of Adaptive Optics Systems with Convolutional Neural Networks
• Pyramid wavefront sensor optical gains compensation using a convolutional model
• Towards on-sky adaptive optics control using reinforcement learning
• Kernel formalism applied to Fourier based wave front sensing in presence of residual phases
• The Visible Integral-field Spectrograph eXtreme (VIS-X): high-resolution spectroscopy with MagAO-X
• Adaptive optics performance of a simulated coronagraph instrument on a large, segmented space telescope in steady state
• Information-theoretical Limits of Recursive Estimation and Closed-loop Control in High-contrast Imaging
• The Bi-O-edge wavefront sensor: How Foucault-knife-edge variants can boost eXtreme Adaptive Optics
• Advances in control of a Pyramid Single Conjugate Adaptive Optics system
• RISTRETTO: a comparative performance analysis of the unmodulated Pyramid wavefront sensor and the Zernike wavefront sensor
• LUVOIR-ECLIPS closed-loop adaptive optics performance and contrast predictions
• The Three-Sided PyramidWavefront Sensor. I. Simulations and Analysis for Astronomical Adaptive Optics