Journal of IKEEE (전기전자학회논문지)

Institute of Korean Electrical and Electronics Engineers (한국전기전자학회)
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A study on vertical alignment liquid crystal devices for electrically polarization controlled camera

전기적 편광 조절형 카메라를 위한 수직 배향형 액정 소자 연구

  • Na-Kyung Lee (Department of Electronic Engineering, Hanbat National University) ;
  • Hyeon-Sik Ahn (Department of Electronic Engineering, Hanbat National University) ;
  • Sung-Min Kim (Department of Electronic Engineering, Hanbat National University) ;
  • Min-Sang Kim (Department of Electronic Engineering, Hanbat National University) ;
  • Seungseo Park (SA-i Technologies) ;
  • Yoonseuk Choi (Department of Electronic Engineering, Hanbat National University)
  • Received : 2023.12.12
  • Accepted : 2023.12.20
  • Published : 2023.12.31
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Abstract

In this study, we propose a liquid crystal-based polarization control technology that can control polarization by adjusting the voltage applied to the liquid crystal, and apply it to a Closed-circuit Television (CCTV) to transmit only the desired angle of polarized light. CCTV with conventional polarizing films cannot control polarization because they focus on backlight compensation, so light reflected from the water surface or highlights reflected from vehicles interfere with subject identification. However, the Vertical Alignment mode allows the polarization to be adjusted electrically, so that only the polarized light at the user's desired angle is transmitted, eliminating reflected highlights. The images obtained using this technique are optimized by computer software. Liquid crystal polarization panels, which can electrically control the polarization angle, transmittance, and polarization rate, have been applied to polarized image monitoring device to improve subject identification in conventional CCTV.

본 연구에서는 액정에 인가되는 전압을 조절하여 편광을 조절할 수 있는 액정 기반 편광 조절 기술을 폐쇄회로 텔레비전(CCTV)에 적용하여 사용자가 원하는 각도의 편광만을 투과시킬 수 있는 시스템을 제안한다. 기존의 편광필름이 적용된 CCTV는 역광 보정 기능에 치중되어 있기 때문에 편광을 제어할 수 없어 수면에서 반사된 빛이나 차량에서 반사된 하이라이트가 피사체 식별을 방해한다. 그러나 Vertical Alignment 모드를 사용하면 전기적으로 편광을 조절할 수 있기 때문에 사용자가 원하는 각도의 편광만 투과시켜 반사되는 하이라이트를 제거할 수 있다. 이 기술을 사용하여 얻은 이미지들은 컴퓨터 소프트웨어에 의해 최적의 이미지로 도출하였다. 편광 각도와 투과율, 편광 속도를 전기적으로 제어할 수 있는 액정 편광 패널을 편광 폐쇄회로 텔레비전에 적용하여 기존 CCTV에서의 피사체 식별을 개선하였다.

Keywords

Acknowledgement

This work was supported by the Basic Science Research Program through the NRF funded by the Ministry of Education (No.2018R1A6A1A03026005) and NRF grant funded by the Korea government (MSIT) (2021R1A2C2011560).

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