Anti-aliasing wave-front reconstruction with Shack-Hartmann sensors

• Type: Article in International Conference Proceedings Book
• Date: 2015

Authors

Bond C.Z. (Author) Other; Correia C. (Author) Other; Teixeira J. (Author) Other; Sauvage J.F. (Author) Other; Véran J.P. (Author) Other; Fusco T. (Author) Other

Conference proceedings International

Title: Adaptive Optics for Extremely Large Telescopes 4 - Conference Proceedings

4th Adaptive Optics for Extremely Large Telescopes, AO4ELT 2015

26 October 2015 through 30 October 2015

Indexing

Scopus - 2 Citations

Other information

Authenticus ID: P-014-ZDD

DOI: 10.20353/k3t4cp1131555

Abstract (EN): The discrete sampling of a wave-front using a Shack-Hartmann sensor limits the maximum spatial frequency we can measure and impacts sensitivity to frequencies at the high end of the correction band due to aliasing. Here we present Wiener filters for wave-front reconstruction in the spatial-frequency domain, ideally suited for systems with a high number of degrees of freedom. We develop a theoretical anti-aliasing (AA) Wiener filter that optimally takes into account high-order wave-front terms folded in-band during the sensing (i.e., discrete sampling) process. We present Monte-Carlo simulation results for residual wave-fronts and propagated noise and compare to standard reconstruction techniques (in the spatial domain). To cope with finite telescope aperture we've developed and optimised a Gerchberg-Saxton like iterative-algorithm that provides superior performance.

Language: English

Type (Professor's evaluation): Scientific