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http://dx.doi.org/10.3807/KJOP.2021.32.6.266

A Study on the Method of Evaluating Optical-system Performance and an Athermal Structure through Thermal Analysis of the Korsch Telescope  

Kim, Kyu-Ho (Department of Nano & Semiconductor Engineering, Korea Polytechnic University)
Park, Seong-Woo (Department of Nano & Semiconductor Engineering, Korea Polytechnic University)
Park, Seung-Han (Department of Optics and Photonics, Yonsei University)
Lee, Kyoung-Mook (Satellite System 2 Team, Hanwha Systems)
Jung, Mee-Suk (Department of Nano & Semiconductor Engineering, Korea Polytechnic University)
Publication Information
Korean Journal of Optics and Photonics / v.32, no.6, 2021 , pp. 266-275 More about this Journal
Abstract
In this paper, a method for evaluating optical-system performance and an athermal structure through thermal analysis of the Korsch telescope was studied. In the case of an optical system having a complex asymmetrical structure, there is a limit to implementing the satellite structure by applying the coefficient of thermal expansion (CTE) in the optical-design software, so it is difficult to evaluate the performance of the optical system against temperature changes. To solve this problem, using mechanical design software all length changes were implemented in all structures that affect the optical system according to temperature, and the value of the change in distance between optical components due to temperature change was organized. Also, the values of changes in shape and thickness of the optical components against temperature changes are organized in the optical-design software. All changes derived from both software packages were applied in the optical software to evaluate the performance of the optical system. As a result, it was found that the MTF for a spatial resolution of 71.4 cycles/mm was maintained at more than 25% in the range from 9 ℃ to 33 ℃. In addition, the performance of the optical system applying the improved structure was evaluated, by finding the structure that had the most influence on the optical system's performance change, and deriving an athermal structure to reduce the effect. As a result, it was found that the MTF for a resolution of 71.4 cycles/mm was maintained at over 67% in the range from 9 ℃ to 33 ℃.
Keywords
Athermal design; Satellite; Structure; Telescope; Thermal analysis;
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Times Cited By KSCI : 2  (Citation Analysis)
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