Paper
16 September 2011 Image plane phase-shifting wavefront sensor for giant telescope active and adaptive optics
François Hénault
Author Affiliations +
Abstract
Since the realization of the twin Keck telescopes of 10-meter diameter built atop the Mauna Kea in Hawaii, the technology of segmented mirrors has become a cornerstone for on-going projects of Extremely Large Telescopes (ELT). Here the individual mirror segments should actually be phased together (i.e. reconstruct the surface of an ideal continuous, giant mirror) within accuracies typically better than one tenth of the operating wavelength. This could be achieved using existing Wavefront Sensors (WFS), but may also involve the development of alternative methods: in this communication is described a new generation WFS operating in the image plane and able to sense differential piston errors of the segments with residual uncertainties inferior to 25 nm by means of a phase-shifting technique. We describe the principle of the method in both monochromatic and polychromatic light and present its achievable performance in terms of limiting magnitude of the guide star in presence of various noise sources. It is emphasized that the technique is also applicable for co-phasing sparse aperture interferometers, or more generally to any Adaptive Optics (AO) system making use of image plane WFS evaluating telescope wavefront errors (WFE) in real time.
© (2011) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
François Hénault "Image plane phase-shifting wavefront sensor for giant telescope active and adaptive optics", Proc. SPIE 8149, Astronomical Adaptive Optics Systems and Applications IV, 81490A (16 September 2011); https://doi.org/10.1117/12.892752
Lens.org Logo
CITATIONS
Cited by 1 scholarly publication.
Advertisement
Advertisement
RIGHTS & PERMISSIONS
Get copyright permission  Get copyright permission on Copyright Marketplace
KEYWORDS
Telescopes

Point spread functions

Image segmentation

Mirrors

Space telescopes

Phase shifts

Adaptive optics

Back to Top