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Investigation of Primary Mirror Segment's Residual Errors for the Thirty Meter TelescopeThe 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.
Document ID
20150008450
Document Type
Conference Paper
External Source(s)
Authors
Seo, Byoung-Joon (Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Nissly, Carl (Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Angeli, George (California Inst. of Tech. Pasadena, CA, United States)
MacMynowski, Doug (California Inst. of Tech. Pasadena, CA, United States)
Sigrist, Norbert (Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Troy, Mitchell (Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Williams, Eric (California Inst. of Tech. Pasadena, CA, United States)
Date Acquired
May 19, 2015
Publication Date
August 2, 2009
Subject Category
Numerical Analysis
Optics
Meeting Information
SPIE Optics and Photonics(San Diego, CA)
Distribution Limits
Public
Copyright
Other
Keywords
warping harness