Share Email Print
cover

Proceedings Paper

Fabrication of mirrors for the Magellan telescopes and the Large Binocular Telescope
Author(s): Hubert M. Martin; Richard G. Allen; James H. Burge; Lee R. Dettmann; Dean A. Ketelsen; Stephen M. Miller; Jose M. Sasian
Format Member Price Non-Member Price
PDF $14.40 $18.00

Paper Abstract

We describe the fabrication and testing of the 6.5 m f/1.25 primary mirrors for the Magellan telescopes and the 8.4 m f/1.14 primary mirrors for the Large Binocular Telescope (LBT). These mirrors, along with the 6.5 m MMT primary, are the fastest and most aspheric large mirrors made. Steward Observatory developed special methods to polish and measure these and other fast mirrors. We use a stressed-lap polishing tool to fit the aspheric surface while providing strong passive smoothing, and computer-generated holograms to verify the measurement of up to 1.4 mm peak-to-valley asphericity to an accuracy of 0.01%. The Magellan mirrors are diffraction-limited at visible wavelengths, with surface accuracies of about 20 nm rms on active supports. We are currently polishing the first LBT primary mirror and preparing to make the thin shells for the LBT adaptive secondary mirrors.

Paper Details

Date Published: 4 February 2003
PDF: 10 pages
Proc. SPIE 4837, Large Ground-based Telescopes, (4 February 2003); doi: 10.1117/12.458606
Show Author Affiliations
Hubert M. Martin, Steward Observatory/Univ. of Arizona (United States)
Richard G. Allen, Steward Observatory/Univ. of Arizona (United States)
James H. Burge, Optical Sciences Ctr./Univ. of Arizona (United States)
Lee R. Dettmann, Steward Observatory/Univ. of Arizona (United States)
Dean A. Ketelsen, Steward Observatory/Univ. of Arizona (United States)
Stephen M. Miller, Steward Observatory/Univ. of Arizona (United States)
Jose M. Sasian, Optical Sciences Ctr./Univ. of Arizona (United States)


Published in SPIE Proceedings Vol. 4837:
Large Ground-based Telescopes
Jacobus M. Oschmann; Larry M. Stepp, Editor(s)

© SPIE. Terms of Use
Back to Top