The secondary mirror concept for the European Extremely Large Telescope

Michael Mueller; Marc Cayrel; Henri Bonnet; Emanuela Ciattaglia; Michael Esselborn; Franz Koch; Herve Kurlandczyk; Lorenzo Pettazzi; Andrew Rakich; Babak Sedghi

doi:10.1117/12.2055109

22 July 2014 The secondary mirror concept for the European Extremely Large Telescope

Michael Mueller, Marc Cayrel, Henri Bonnet, Emanuela Ciattaglia, Michael Esselborn, Franz Koch, Herve Kurlandczyk, Lorenzo Pettazzi, Andrew Rakich, Babak Sedghi

Author Affiliations +

Proceedings Volume 9145, Ground-based and Airborne Telescopes V; 91451I (2014) https://doi.org/10.1117/12.2055109
Event: SPIE Astronomical Telescopes + Instrumentation, 2014, Montréal, Quebec, Canada

Abstract

The E-ELT is an active and adaptive 39-m telescope, with an anastigmat optical solution (5 mirrors including two flats), currently being developed by the European Southern Observatory (ESO). The convex 4-metre-class secondary mirror (M2) is a thin Zerodur meniscus passively supported by an 18 point axial whiffletree. A warping harness system allows to correct low order deformations of the M2 Mirror. Laterally the mirror is supported on 12 points along the periphery by pneumatic jacks. Due to its high optical sensitivity and the telescope gravity deflections, the M2 unit needs to allow repositioning the mirror during observation. Considering its exposed position 30m above the primary, the M2 unit has to provide good wind rejection. The M2 concept is described and major performance characteristics are presented.

Citation Download Citation

Michael Mueller, Marc Cayrel, Henri Bonnet, Emanuela Ciattaglia, Michael Esselborn, Franz Koch, Herve Kurlandczyk, Lorenzo Pettazzi, Andrew Rakich, and Babak Sedghi "The secondary mirror concept for the European Extremely Large Telescope", Proc. SPIE 9145, Ground-based and Airborne Telescopes V, 91451I (22 July 2014); https://doi.org/10.1117/12.2055109

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