Applications of Multi-Point Mirror Supporting

Abstract:

Primary mirror (PM) supporting system design is one of the key components to the design of a telescope. This paper presents applications of extended multi-point supporting structures that are employed in ground based theodolites, 3 points positioning-9 points supporting system and 18 points supporting system. A number of theoretical studies have been performed using Finite Element Analysis (FEA) on each supporting system, in which the extended multi-point supporting system to 0.6-m and 1-m diameter primary mirror is particularly focused. Analyzing Zerodur major mirrors with a diameter to thickness ratio less than 7.3, deformation due to supporting gives an RMS value less than 6-nm which is 24% of the design requirement of 60-nm. Series of experiments have also been conducted using 4-D interferometer. The deformation due to supporting of major mirror has been predominantly suppressed mainly by deformation during the fabrication process. This indicates that the above supporting systems perform an excellent task under given conditions.

• Periodical: Applied Mechanics and Materials (Volumes 475-476)
• Pages: 1555-1558
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.475-476.1555
• Online since: December 2013
• Authors: Ren Shan Zhuo, Dong Ge Zhang
• Keywords: Interference Measurement, Mirror Supporting, Primary Mirror

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