The Telescope Primary Mirror Isostatic Mount Bonding Position Analysis

Abstract:

The telescope primary mirror Isostatic Mount (ISM) design is an important issue for optical performance. The ISM bonding position will affect the telescope performance. The primary mirror reflection surface is parallel with gravity force during telescope alignment process. Thus, the distance between ISM geometry center and primary mirror center of gravity will lead mirror surface deformation. The ISM mounting mainly aberration is astigmatism at mirror surface. This study is applied Finite Element (FEM) simulate mirror surface deformation and using Zernike polynomial fitting the mirror surface aberration. The simulation result show the ISM bonding at mirror neutral plane the aberration will minimum at 1G gravity. The ISM bonding position errors also affect aberration distribution.

• Periodical: Applied Mechanics and Materials (Volumes 284-287)
• Pages: 2812-2815
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.284-287.2812
• Online since: January 2013
• Authors: Ming Ying Hsu, W.C. Lin, Chia Yen Chan, C. F. Ho, S.T. Chang, Ting Ming Huang
• Keywords: Aberration, Astigmatism, Finite Element Method (FEM), ISM, Zernike Polynomial

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