Share Email Print
cover

Proceedings Paper

Investigation of primary mirror segment's residual errors for the Thirty Meter Telescope
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 primary mirror segment aberrations after shape corrections with warping harness have been identified as the single largest error term in the Thirty Meter Telescope (TMT) image quality error budget. In order to better understand the likely errors and how they will impact the telescope performance we have performed detailed simulations. We first generated unwarped primary mirror segment surface shapes that met TMT specifications. Then we used the predicted warping harness influence functions and a Shack-Hartmann wavefront sensor model to determine estimates for the 492 corrected segment surfaces that make up the TMT primary mirror. Surface and control parameters, as well as the number of subapertures were varied to explore the parameter space. The corrected segment shapes were then passed to an optical TMT model built using the Jet Propulsion Laboratory (JPL) developed Modeling and Analysis for Controlled Optical Systems (MACOS) ray-trace simulator. The generated exit pupil wavefront error maps provided RMS wavefront error and image-plane characteristics like the Normalized Point Source Sensitivity (PSSN). The results have been used to optimize the segment shape correction and wavefront sensor designs as well as provide input to the TMT systems engineering error budgets.

Paper Details

Date Published: 1 October 2009
PDF: 10 pages
Proc. SPIE 7427, Optical Modeling and Performance Predictions IV, 74270F (1 October 2009); doi: 10.1117/12.828046
Show Author Affiliations
Byoung-Joon Seo, Jet Propulsion Lab. (United States)
California Institute of Technology (United States)
Carl Nissly, Jet Propulsion Lab. (United States)
California Institute of Technology (United States)
George Angeli, Thirty Meter Telescope Project (United States)
Doug MacMynowski, Thirty Meter Telescope Project (United States)
Norbert Sigrist, Jet Propulsion Lab. (United States)
California Institute of Technology (United States)
Mitchell Troy, Jet Propulsion Lab. (United States)
California Institute of Technology (United States)
Eric Williams, Thirty Meter Telescope Observatory (United States)


Published in SPIE Proceedings Vol. 7427:
Optical Modeling and Performance Predictions IV
Mark A. Kahan, Editor(s)

© SPIE. Terms of Use
Back to Top