
Proceedings Paper
Ion figuring of large prototype mirror segments for the E-ELTFormat | Member Price | Non-Member Price |
---|---|---|
$17.00 | $21.00 |
Paper Abstract
At INAF-Astronomical Observatory of Brera a study is under way to explore the problems related to the ion beam
figuring of full scale Zerodur hexagonal mirrors of M1 for the European Extremely Large Telescope (E-ELT), having
size of 1.4 m corner to corner. During this study it is initially foreseen the figuring of a scaled down version mirror of the
same material having size of 1 m corner to corner to assess the relevant figuring problems and issues. This specific
mirror has a radius of curvature of 3 m, which allows for easy interferometric measurement. A mechanical support was
designed to minimize its deformations due to the gravity. The Ion Beam Figuring Facility used for this study has been
recently completed in the Brera Observatory and has a figuring area of 140 cm x 170 cm. It employs a Kaufman ion
source having 50 mm grids mounted on three axis. This system has been designed and developed to be autonomous and
self-monitoring during the figuring process. The software and the mathematical tools used to compute the dwell time
solution have been developed at INAF-OAB as well. Aim of this study is the estimation and optimization of the time
requested to correct the surface adopting strategies to mitigate the well-known thermal problems related to the Zerodur
material. In this paper, the results obtained figuring the 1 m corner-to-corner test segment are reported.
Paper Details
Date Published: 28 July 2014
PDF: 12 pages
Proc. SPIE 9151, Advances in Optical and Mechanical Technologies for Telescopes and Instrumentation, 91510Q (28 July 2014); doi: 10.1117/12.2056769
Published in SPIE Proceedings Vol. 9151:
Advances in Optical and Mechanical Technologies for Telescopes and Instrumentation
Ramón Navarro; Colin R. Cunningham; Allison A. Barto, Editor(s)
PDF: 12 pages
Proc. SPIE 9151, Advances in Optical and Mechanical Technologies for Telescopes and Instrumentation, 91510Q (28 July 2014); doi: 10.1117/12.2056769
Show Author Affiliations
M. Ghigo, INAF - Osservatorio Astronomico di Brera (Italy)
G. Vecchi, INAF - Osservatorio Astronomico di Brera (Italy)
S. Basso, INAF - Osservatorio Astronomico di Brera (Italy)
O. Citterio, INAF - Osservatorio Astronomico di Brera (Italy)
G. Vecchi, INAF - Osservatorio Astronomico di Brera (Italy)
S. Basso, INAF - Osservatorio Astronomico di Brera (Italy)
O. Citterio, INAF - Osservatorio Astronomico di Brera (Italy)
M. Civitani, INAF - Osservatorio Astronomico di Brera (Italy)
E. Mattaini, INAF - Osservatorio Astronomico di Brera (Italy)
G. Pareschi, INAF - Osservatorio Astronomico di Brera (Italy)
G. Sironi, INAF - Osservatorio Astronomico di Brera (Italy)
E. Mattaini, INAF - Osservatorio Astronomico di Brera (Italy)
G. Pareschi, INAF - Osservatorio Astronomico di Brera (Italy)
G. Sironi, INAF - Osservatorio Astronomico di Brera (Italy)
Published in SPIE Proceedings Vol. 9151:
Advances in Optical and Mechanical Technologies for Telescopes and Instrumentation
Ramón Navarro; Colin R. Cunningham; Allison A. Barto, Editor(s)
© SPIE. Terms of Use
