Journal of Satellite, Information and Communications (한국위성정보통신학회논문지)

Korea Society of Satellite Technology (한국위성정보통신학회)
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Optical Design for High Brightness Direct Type Backlight Unit Using Medical LCD Application

의료용 초고휘도 LCD 소자를 위한 직하형 Backlight의 최적설계

  • Received : 2016.07.29
  • Accepted : 2016.08.30
  • Published : 2016.09.30
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Abstract

In this study, it was investigated about optical simulation in highg brightness and high uniformity direct-type backlight design for medical application. Direct-type backlight has been used high-brightness backlight such as Medical LCD application. The key parameter in designing direct-type backlight was consists of three geometrical dimension such as the distance of two lamps, the gap of lamp and reflection plate and the number of lamps. It has many of variations in optical design and it causes the different properties in backlight system. It shows the best values of above parameters; 26mm of the distance of two lamps, 4.5mm of the gap of lamp and reflection plate and 16 lamps. And we produced the specimen as above condition, and acquired good result in backlight such as the value of the brightness is 6423 nit in center of emission area and less than 5% in brightness uniformity. It shows the effective ways of designing backlight system using optical simulation method for medical LCD application.

본 연구에서는 최근 의료용으로 많이 사용되고 있는 고휘도, 고균일도의 직하광원구조를 가지는 백라이트 유닛에 대한 설계 시뮬레이션을 실시하였다. 직하형 백라이트 시스템은 기존의 Edge-Lighr 방식에 비해서 고휘도 및 고균일도를 달성할 수 있어 의료용 판독이 요구되는 고품질의 디스플레이에 사용되고 있으며, 흑백이미지를 바탕으로 진단을 실시하는 경우가 많기 때문에 휘도 및 휘도 균일도에 대한 높은 성능이 요구되는 분야이다. 본 연구에서는 복수 개의 램프를 수평으로 배열한 경우에 각 램프간의 거리 및 반사판과의 거리, 상측 확산판과의 거리에 대한 최적설계를 실시하고, 이 결과를 바탕으로 실물과 유사한 조건에서 시뮬레이션을 실시하였다. 연구 결과, Parameter 에 의존하는 변수를 최적화 할 수 있었으며, 4.5mm 의 램프와 반사판 거리 및 26mm 의 램프간 거리를 바탕으로 16개의 램프를 배치하여, 32인치 크기의 화면에서 6423nit 의 중심휘도를 갖는 고품위의 우수한 광원의 설계가 가능함을 확인할 수 있었다.

Keywords

References

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