Journal of The Korean Astronomical Society (천문학회지)

The Korean Astronomical Society (한국천문학회)
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DEVELOPMENT OF LIGHTWEIGHT OPTICAL TELESCOPE KIT USING ALUMINUM PROFILE AND ISOGRID STRUCTURE

  • Park, Woojin (Korea Astronomy and Space Science Institute) ;
  • Lee, Sunwoo (Division of Scientific Instrumentation and Management, Korea Basic Science Institute) ;
  • Han, Jimin (School of Space Research and Institute of Natural Sciences, Kyung Hee University) ;
  • Ahn, Hojae (School of Space Research and Institute of Natural Sciences, Kyung Hee University) ;
  • Ji, Tae-Geun (School of Space Research and Institute of Natural Sciences, Kyung Hee University) ;
  • Kim, Changgon (School of Space Research and Institute of Natural Sciences, Kyung Hee University) ;
  • Kim, Dohoon (Department of Astronomy & Space Science, Kyung Hee University) ;
  • Lee, Sumin (Department of Astronomy & Space Science, Kyung Hee University) ;
  • Kim, Young-Jae (Graduate School of Analytical Science and Technology (GRAST), Chungnam National University) ;
  • Kim, Geon-Hee (Graduate School of Analytical Science and Technology (GRAST), Chungnam National University) ;
  • Kim, Junghyun (SLLAB, INC.) ;
  • Kim, Ilhoon (SLLAB, INC.) ;
  • Pak, Soojong (School of Space Research and Institute of Natural Sciences, Kyung Hee University)
  • Received : 2021.03.16
  • Accepted : 2022.01.04
  • Published : 2022.02.28
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Abstract

We introduce the Transformable Reflective Telescope (TRT) kit that applies an aluminum profile as a base plate for precise, stable, and lightweight optical system. It has been utilized for optical surface measurements, developing alignment and baffle systems, observing celestial objects, and various educational purposes through Research & Education projects. We upgraded the TRT kit using the aluminum profile and truss and isogrid structures for a high-end optical test device that can be used for prototyping of precision telescopes or satellite optical systems. Thanks to the substantial aluminum profile and lightweight design, mechanical deformation by self-weight is reduced to maximum 67.5 ㎛, which is an acceptable misalignment error compared to its tolerance limits. From the analysis results of non-linear vibration simulations, we have verified that the kit survives in harsh vibration environments. The primary mirror and secondary mirror modules are precisely aligned within 50 ㎛ positioning error using the high accuracy surface finished aluminum profile and optomechanical parts. The cross laser module helps to align the secondary mirror to fine-tune the optical system. The TRT kit with the precision aluminum mirror guarantees high quality optical performance of 5.53 ㎛ Full Width at Half Maximum (FWHM) at the field center.

Keywords

Acknowledgement

This research was supported by the Kyung Hee University Leaders in Industry-University Cooperation granted by the Ministry of Education (LINK+ Project No. 1345323331), and by the National Research Council of Science & Technology (NST) grant by the Korea government (MSIT) (No. CAP-19-01-KASI).

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