Share Email Print

Proceedings Paper

Optical quality and stability of 1.8-m aluminum mirrors
Author(s): Philippe Dierickx
Format Member Price Non-Member Price
PDF $14.40 $18.00
cover GOOD NEWS! Your organization subscribes to the SPIE Digital Library. You may be able to download this paper for free. Check Access

Paper Abstract

Within the framework of the NTT 3.5-m and VLT 8-m telescopes' projects, ESO has been trying to assess the potential interest of Aluminum as a substrate for large astronomical mirrors. After a series of test on 500-mm diameter Aluminum mirrors two 1.8-m diameter Aluminum blanks were ordered and produced according to totally different manufacturing processes. Both blanks were figured within specifications, and successfully underwent a series of thermal cycles aimed at verifying their long-term stability towards relaxation of internal stresses. While in the 8-m range the baseline solution selected by ESO, partly for schedule reasons, was the glass-ceramics substrate, the results obtained so far with Aluminum have been undoubtedly positive. Aluminum is considered as a potentially cost and performance- effective substrate for active telescopes, at least in the four- meter range. Further tests are however still required to validate the technology.

Paper Details

Date Published: 15 October 1993
PDF: 7 pages
Proc. SPIE 1931, Metal Mirrors, (15 October 1993); doi: 10.1117/12.158746
Show Author Affiliations
Philippe Dierickx, European Southern Observatory (Germany)

Published in SPIE Proceedings Vol. 1931:
Metal Mirrors
Richard G. Bingham; David D. Walker, Editor(s)

© SPIE. Terms of Use
Back to Top