Fabrication of Anti-Moiré Filter Using Multi-Array Needle Coating for LED Screens

다중 배열 니들 코팅을 이용한 LED 스크린용 Anti-Moiré 필터 제작

  • Jeon, Kyungjun (School of Electrical & Electronic & Communication Engineering, Korea University of Technology and Education) ;
  • Lee, Jinyoung (Interdisciplinary Program in Creative Engineering, Korea University of Technology and Education) ;
  • Park, Jongwoon (School of Electrical & Electronic & Communication Engineering, Korea University of Technology and Education)
  • 전경준 (한국기술교육대학교 전기.전자.통신공학부) ;
  • 이진영 (한국기술교육대학교 창의융합공학협동과정) ;
  • 박종운 (한국기술교육대학교 전기.전자.통신공학부)
  • Received : 2021.03.10
  • Accepted : 2021.03.18
  • Published : 2021.03.31

Abstract

Using a multi-array needle module developed for coating of high-density cylindrical microlens array (C-MLA), we have fabricated an anti-Moiré filter for LED screens. The Moiré phenomenon appears due to the interference between the array pattern of image sensors in a camera and the non-emission area (grid pattern) of a LED screen. To suppress it, we have employed poly(methyl methacrylate) (PMMA) and coated it on a glass substrate in the form of a grid and non-grid (parallel lines). We have rotated the needle module in order to increase the number of C-MLAs. With this scheme, we have fabricated the 150 mm × 150 mm anti-Moiré filters where 836 microlens lines are formed. They show the average width of 255.4 ㎛, the average distance between CMLs of 94.6 ㎛, and C-MLA width non-uniformity of 4.7%. We have shown that the Moiré patterns still appear in the presence of the parallel (non-grid)-type filter, whereas they disappeared completely by the grid-type filter. It is due to the fact that the Moiré patterns are diffused more effectively by the grid-type C-MLA.

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