Current Optics and Photonics

  • 제7권4호
  • /
  • Pages.435-442
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  • 2023
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  • 2508-7266(pISSN)
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  • 2508-7274(eISSN)
한국광학회 (Optical Society of Korea)
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Optimal Design of a Coudé Mirror Assembly for a 1-m Class Ground Telescope

  • Jaehyun Lee (Korea Research Institute of Standards and Science (KRISS)) ;
  • Hyug-Gyo Rhee (Korea Research Institute of Standards and Science (KRISS)) ;
  • Eui Seung Son (Defense Rapid Acquisition Technology Research Institute) ;
  • Jeon Geon Kang (Defense Rapid Acquisition Technology Research Institute) ;
  • Ji-Young Jeong (Hanwha Systems) ;
  • Pilseong Kang (Korea Research Institute of Standards and Science (KRISS))
  • 투고 : 2023.04.06
  • 심사 : 2023.06.14
  • 발행 : 2023.08.25
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초록

These days, the size of a reflective telescope has been increasing for astronomical observation. An additional optical system usually assists a large ground telescope for image analysis or the compensation of air turbulence. To guide collimated light to the external optical system through a designated path, a coudé mirror is usually adopted. Including a collimator, a coudé mirror of a ground telescope is affected by gravity, depending on the telescope's pointing direction. The mirror surface is deformed by the weight of the mirror itself and its mount, which deteriorates the optical performance. In this research, we propose an optimization method for the coudé mirror assembly for a 1-m class ground telescope that minimizes the gravitational surface error (SFE). Here the mirror support positions and the sizes of the mount structure are optimized using finite element analysis and the response surface optimization method in both the horizontal and vertical directions, considering the telescope's altitude angle. Throughout the whole design process, the coefficients of the Zernike polynomials are calculated and their amplitude changes are monitored to determine the optimal design parameters. At the same time, the design budgets for the thermal SFE and the mass and size of the mount are reflected in the study.

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과제정보

This work was supported by the Defense Rapid Acquisition Technology Research Institute (DRATRI) - Grant funded by Defense Acquisition Program Administration (DAPA) (UC200012D).

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