Share Email Print
cover

Proceedings Paper

Design and manufacture of 8.4 m primary mirror segments and supports for the GMT
Author(s): H. M. Martin; J. R. P. Angel; J. H. Burge; B. Cuerden; W. B. Davison; M. Johns; J. S. Kingsley; L. B. Kot; R. D. Lutz; S. M. Miller; S. A. Shectman; P. A. Strittmatter; C. Zhao
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

The design, manufacture and support of the primary mirror segments for the GMT build on the successful primary mirror systems of the MMT, Magellan and Large Binocular telescopes. The mirror segment and its support system are based on a proven design, and the experience gained in the existing telescopes has led to significant refinements that will provide even better performance in the GMT. The first 8.4 m segment has been cast at the Steward Observatory Mirror Lab, and optical processing is underway. Measurement of the off-axis surface is the greatest challenge in the manufacture of the segments. A set of tests that meets the requirements has been defined and the concepts have been developed in some detail. The most critical parts of the tests have been demonstrated in the measurement of a 1.7 m off-axis prototype. The principal optical test is a full-aperture, high-resolution null test in which a hybrid reflective-diffractive null corrector compensates for the 14 mm aspheric departure of the off-axis segment. The mirror support uses the same synthetic floatation principle as the MMT, Magellan, and LBT mirrors. Refinements for GMT include 3-axis actuators to accommodate the varying orientations of segments in the telescope.

Paper Details

Date Published: 6 July 2006
PDF: 12 pages
Proc. SPIE 6273, Optomechanical Technologies for Astronomy, 62730E (6 July 2006); doi: 10.1117/12.672149
Show Author Affiliations
H. M. Martin, Steward Observatory, Univ. of Arizona (United States)
J. R. P. Angel, Steward Observatory, Univ. of Arizona (United States)
J. H. Burge, Steward Observatory, Univ. of Arizona (United States)
College of Optical Sciences, Univ. of Arizona (United States)
B. Cuerden, Steward Observatory, Univ. of Arizona (United States)
W. B. Davison, Steward Observatory, Univ. of Arizona (United States)
M. Johns, Carnegie Observatories (United States)
J. S. Kingsley, Steward Observatory, Univ. of Arizona (United States)
L. B. Kot, Steward Observatory, Univ. of Arizona (United States)
R. D. Lutz, Steward Observatory, Univ. of Arizona (United States)
S. M. Miller, Steward Observatory, Univ. of Arizona (United States)
S. A. Shectman, Carnegie Observatories (United States)
P. A. Strittmatter, Steward Observatory, Univ. of Arizona (United States)
C. Zhao, College of Optical Sciences, Univ. of Arizona (United States)


Published in SPIE Proceedings Vol. 6273:
Optomechanical Technologies for Astronomy
Eli Atad-Ettedgui; Joseph Antebi; Dietrich Lemke, Editor(s)

© SPIE. Terms of Use
Back to Top