중공 미소 유리구를 이용한 LED 스크린 모아레 억제

Suppression of Moiré Fringes Using Hollow Glass Microspheres for LED Screen

  • 홍송은 (한국기술교육대학교 전기.전자.통신공학부) ;
  • 나정필 (한국기술교육대학교 전기.전자.통신공학부) ;
  • 정모세 (한국기술교육대학교 전기.전자.통신공학부) ;
  • 김기은 (한국기술교육대학교 전기.전자.통신공학부) ;
  • 박종운 (한국기술교육대학교 전기.전자.통신공학부)
  • Songeun Hong (School of Electrical & Electronic & Communication Engineering, Korea University of Technology and Education) ;
  • Jeongpil Na (School of Electrical & Electronic & Communication Engineering, Korea University of Technology and Education) ;
  • Mose Jung (School of Electrical & Electronic & Communication Engineering, Korea University of Technology and Education) ;
  • Gieun Kim (School of Electrical & Electronic & Communication Engineering, Korea University of Technology and Education) ;
  • Jongwoon Park (School of Electrical & Electronic & Communication Engineering, Korea University of Technology and Education)
  • 투고 : 2023.07.12
  • 심사 : 2023.09.11
  • 발행 : 2023.09.30

초록

Moiré patterns emerge due to the interference between the non-emission area of the LED screen and the grid line in an image sensor of a video recording device when taking a video in the presence of the LED screen. To reduce the moiré intensity, we have fabricated an anti-moiré filter using hollow glass microspheres (HGMs) by slot-die coating. The LED screen has a large non-emission area because of a large pitch (distance between LED chips), causing more severe moiré phenomenon, compared with a display panel having a very narrow black matrix (BM). It is shown that HGMs diffuse light in such a way that the periodicity of the screen is broken and thus the moiré intensity weakens. To quantitatively analyze its moiré suppression capability, we have calculated the spatial frequencies of the moiré fringes using fast Fourier transform. It is addressed that the moiré phenomenon is suppressed and thus the amplitude of each discrete spatial frequency term is reduced as the HGM concentration is increased. Using the filter with the HGM concentration of 9 wt%, the moiré fringes appeared depending sensitively on the distance between the LED screen and the camera are almost completely removed and the visibility of a nature image is enhanced at a sacrifice of luminance.

키워드

과제정보

This research was supported by "Regional Innovation Strategy (RIS)" through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (MOE) (2021RIS-004).

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