Korean Journal of Optics and Photonics (한국광학회지)

Optical Society of Korea (한국광학회)
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Focus-adjustment Method for a High-magnification Zoom-lens System

고배율 줌 광학계의 상면 오차 보정 방법

  • Jae Myung Ryu (Department of Optical Engineering, Kumoh National Institute of Technology)
  • 유재명 (국립금오공과대학교 광시스템공학과)
  • Received : 2023.02.23
  • Accepted : 2023.03.15
  • Published : 2023.04.25
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Abstract

Zoom lenses are now starting to be applied to mobile-phone cameras as well. A zoom lens applied to a mobile-phone camera is mainly used to capture images in the telephoto range. Such an optical system has a long focal length, similar to that of a high-magnification zoom optical system, so the position of the imaging device also shifts significantly, due to manufacturing errors of the lenses and mechanical parts. In the past, the positional shift of the imaging device was corrected by moving the first lens group and the total optical system, but this paper confirms that the position of the imaging device can be corrected by selecting any two moving lens groups. However, it is found that more distance must be secured in the front and rear of a moving lens group for this purpose.

줌 렌즈는 이제 휴대폰에도 적용되기 시작했다. 휴대폰에 적용되는 줌 렌즈는 주로 망원 영역을 촬영하기 위해 적용되고 있으며, 이러한 광학계는 고배율 줌 광학계와 유사하게 초점거리가 길어서 부품의 제작 오차에 의한 촬상 소자의 위치도 크게 변한다. 이를 보정하기 위해 기존에는 렌즈군 1군과 광학계 전체를 이동해서 촬상 소자의 위치 변화를 보정했으나, 본 논문에서는 이동하는 렌즈군 2개를 임의로 선택해서 촬상 소자의 위치를 보정할 수 있음을 확인했다. 다만, 이를 위해서는 이동하는 렌즈군 앞쪽과 뒤쪽으로 간격을 더 확보해야 함을 알 수 있었다.

Keywords

Acknowledgement

이 논문은 2020년도 정부(교육부)의 재원으로 한국연구재단의 지원을 받아 수행된 지역우수과학자지원사업임(과제번호: NRF-2020R1I1A3052712).

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