Disentangling between low order telescope aberrations and segmentation errors using a Shack-Hartmann sensor

R. Mazzoleni; N. Yaitskova; L. Noethe

doi:10.1117/12.789254

17 July 2008 Disentangling between low order telescope aberrations and segmentation errors using a Shack-Hartmann sensor

R. Mazzoleni, N. Yaitskova, L. Noethe

Author Affiliations +

Proceedings Volume 7012, Ground-based and Airborne Telescopes II; 701216 (2008) https://doi.org/10.1117/12.789254
Event: SPIE Astronomical Telescopes + Instrumentation, 2008, Marseille, France

Abstract

The shape correction of the mirrors is a crucial operation to obtain diffraction limited images in actively controlled telescopes. If the mirror is not monolithic, the segmentation errors introduced by piston, tip and tilt of the segments are superimposed on the continuous aberrations. In the case of a sensor based on the measurement of the wave front slopes, like the Shack-Hartmann wave front sensor, an algorithm which allows separating the different contributions is necessary for a proper correction. In the framework of the Active Phasing Experiment (APE) carried out at ESO, we have developed a simple algorithm which can be applied to compute the aberrations and the tip-tilt coefficients using the information obtained with a Shack-Hartmann sensor. It is based on the construction of an orthogonal base in the space of the wave front slope functions. The description of the algorithm and its performance in the cases of low-order aberrations superimposed on tip-tilt misalignment of the segments are reported. A particular application of this technique in the case of the European Extremely Large Telescope (E-ELT) is discussed and the expected upper limits for the residual errors after correction are estimated.

Citation Download Citation

R. Mazzoleni, N. Yaitskova, and L. Noethe "Disentangling between low order telescope aberrations and segmentation errors using a Shack-Hartmann sensor", Proc. SPIE 7012, Ground-based and Airborne Telescopes II, 701216 (17 July 2008); https://doi.org/10.1117/12.789254

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available