• Proceedings of the Korean Information Science Society Conference
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• 2003.04a
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• pp.139-141
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• 2003

최근의 휴대용 시스템에서는 디스플레이로 투과형 LCD를 주로 채택하고 있다. 투과형 LCD는 후면조명이 광원이 되는데, 후면조명(Backlight)의 소비전력이 시스템 전체 소비 전력에서 큰 비중을 차지한다. 우리는 화질의 큰 저하 없이 후면조명의 소비 전력을 줄이는 방법인 DLS를 소개한다. 본 논문에서는 DLS 구현과 구현한 플랫폼에서의 실험결과를 간단히 언급한다.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2009.10a
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• pp.69-72
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• 2009

Recently, LED(Light Emitting Diode) TV has attracted greate attention due to its super-slim form factore as well as low power consumption. LED TV is actually an LCD(Liquid Crystal Display) TV in which edge-lit LED backlight is adopted. In the presente study, we report on the comparison of optical characteristics 55-inch edge-lit LED backlight and CCFL(Cold Cathode Fluorescent Lam)backlight. The angular distribution of the luminance and the on-axis luminance gain on each optical component were investigated and compared. The effect of the backlight structure on the performance of the optical films was studied and discussed.

• Proceedings of the Korean Information Science Society Conference
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• 2003.04a
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• pp.812-814
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• 2003

LCD(Liquid Crystal Display)는 표시장치로 실용화된 후 많은 상품에 적용되고 있다 그러나 LCD는 자체 발광 능력이 없으므로 그 후면에서 LCD 화면을 밝혀주는 BLU(Backlight Unit)를 필요로 한다. BLU는 내부 광원으로 밝기가 균일한 평면광을 만들어 LCD 화면을 균일하게 면조사하는 역할을 한다. LCD의 표시 품질을 향상시키기 위해, 균일한 평면광을 만들어내는 BLU를 제작하기 위한 다양한 방법이 개발되고 있다. 본 논문에서는 이러한 BLU를 제작하는 툴(Tool)과 제작린 BLU가 생성하는 평면광의 휘도 분포를 예측하는 시뮬레이터를 제안함으로써 BLU 개발에 소요되는 시간 및 비용을 단축할 수 있도록 한다.

• Journal of Information Display
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• v.11 no.2
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• pp.76-83
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• 2010

This paper presents the multi-user autostereoscopic 3D display system constructed and operated by the authors using the time-multiplexing approach. This prototype has three main advantages over the previous versions developed by the authors: its hardware was simplified as only one optical array is used to create viewing regions in space, a lenticular multiplexing screen is not necessary as images can be produced sequentially on a fast 120Hz LCD with full resolution, and the holographic projector was replaced with a high-frame-rate digital micromirror device (DMD) projector. The whole system in this prototype consists of four major parts: a 120Hz high-frame-rate DMD projector, a 49-element optical array, a 120Hz screen assembly, and a multi-user head tracker. The display images for the left/right eyes are produced alternatively on a 120Hz direct-view LCD and are synchronized with the output of the projector, which acts as a backlight of the LCD. The novel steering optics controlled by the multiuser head tracker system directs the projector output to regions referred to as exit pupils, which are located in the viewers’eyes. The display can be developed in the "hang-on-the-wall"form.

• The Transactions of the Korean Institute of Power Electronics
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• v.13 no.5
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• pp.376-382
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• 2008

In this paper, scanning backlight unit which can reduce motion blur was designed and fabricated using flat fluorescent lamp. The FFL(flat fluorescent lamp) is in the limelight as a new illuminant of next generation BLU(backlight unit), because of simple assembly and reduction of driving components. In order to control lamp brightness, lamp on-time was controlled. In this experiment, it was confirmed that lamp brightness can be dimmed linealy and in a wide range.

• Journal of the Optical Society of Korea
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• v.12 no.3
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• pp.174-177
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• 2008

The luminance properties of FFL(Flat Fluorescent Lamp) backlights have been investigated in detail for the first time. The on-axis luminance gain as well as viewing-angle characteristics on various combinations of optical films were obtained from FFL backlight and compared to the results of conventional CCFL(cold-cathode fluorescent lamps) backlights. It was found that the on-axis luminance gains achieved by using optical films in the FFL backlight were lower than those in the CCFL backlight indicating that the recycling processes occurring between optical films and light sources/reflection sheet are not so effective in the FFL backlight due to the much larger area of, and thus higher absorption probability of the FFL. This result suggests that new optical films should be developed for FFL backlight and other flat-lamp backlight technologies.

• Proceedings of the Korean Information Science Society Conference
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• 2004.10a
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• pp.673-675
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• 2004

컴퓨터 시스템의 구성 요소인 디스플레이 시스템은 가장 많은 전력을 소모하는 장치이다. 디스플레이 시스템의 전력을 효과적으로 줄이기 위하여 이미지 제어, 주파수 제어 등이 있지만 가장 효과적인 것은 LCD 패널부와 백라이트(backlight)를 제어하는 것이다. 본 논문에서는 디스플레이 시스템에서 DDC(Display Data Channel)를 이용하여 패널과 백 라이트 전압 레벨을 조절하여 저전력을 구현하였다. 호스트(PC)에서 동작하는 응용프로그램의 작성과 호스트의 영령을 받아 처리할 수 있는 디스플레이부를 구현하였다. 데스크탑 컴퓨터와 15, 17인치 LCD(Liquid Crystal Display) 모니터에서 소비 전력을 측정하였으며, 2-86%정도의 소비 전력을 줄이는 결과를 확인하였다.

• Proceedings of the Korean Information Science Society Conference
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• 2003.10a
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• pp.514-516
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• 2003

LCD(Liquid Crystal Display)는 자체 발광능력이 없으므로 그 후면에서 LCD 화면을 밝혀주는 BLU(Backlight Unit)를 필요로 한다. BLU의 핵심부품으로써 광원으로부터 나온 빛을 LCD의 패널 방향으로 이끌어내는 역할을 담당하고 있는 부분이 바로 도광판이고, 빛을 패널 방향으로 고르게 분포시키기 위해 도광판 하부에 점 모양의 확산물질을 인쇄한다. 이 인쇄패턴은 광원으로부터의 거리에 따라서 그 크기를 다르게 함으로써 패널 부분으로 균일한 평면광을 생성하도록 한다. 따라서 보다 균일한 평면광을 생성하는 BLU를 개발하기 위해서는 주어진 조건에서 패널 부분으로 균일한 평면광을 생성하도록 설계된 인쇄패턴을 찾는 것이 관건이다. 이러한 인쇄패턴을 Simplex Search 알고리즘을 사용하여 자동으로 찾게 함으로써 수작업으로 찾는 것보다 빠른 시간 내에 더욱 효율적인 인쇄패턴을 찾도록 한다.

• Journal of Information Display
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• v.5 no.1
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• pp.7-15
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• 2004

A highly simplified backlight unit mainly composed of diffractive grating in sub-micron order imprinted light-guide plate (LGP) is proposed for edge-lit backlight unit. Optical characteristics of the imprinted LGP are examined by RCWA and the performance is verified through Monte Carlo simulation. Results show that the diffraction efficiency, luminous flux and its uniformity over the area are significantly affected by the angle of incident ray. Consequently couples of design considerations are additionally proposed to enhance luminous flux. In terms of peak luminance and out-coupling luminous flux, the experimental results are agreed well with the performance simulation. Finally, compared with optical characteristics of conventional backlight unit, we could conclude that the proposed simplified backlight unit made of diffractive grating imprinted light-guide plate is a good substitute for the conventional backlight unit.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.940-941
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• 2015

LCD (liquid crystal display) industry is needed to goods of high reliability and is interested in products without harmful material. In this experiment, we made the LED backlight unit for Automotive-navigation. And for making this backlight unit we used to eight side emitting type white LEDs with 1W high power of the lumileds company. We could know that this backlight unit releases to 6500 nit in 14W power consumption and start up voltage time is under the15ms in the ambient temperature $-20^{\circ}C$.