• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권2호
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• pp.1515-1518
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• 2007

We demonstrate a high color gamut liquid crystal display (LCD) system (>100 %) by using a precompensated tri-chromatic LED-backlight module over a temperature range of (25 to $70^{\circ}C$), whose pre-compensated optical characteristic balances the spectral redshift and intensity decrease due to the temperature rising during operation.

• 반도체디스플레이기술학회지
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• 제7권2호
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• pp.29-33
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• 2008

LCD panels are increasingly used to show moving image material, for example in LCD television sets. However, moving images become blurred on LCD panels. One of the causes of motion blur is the slow reaction of LC(liquid crystal) cell to change in the pixel value. Another cause of motion blur is the hold-type characteristic of the LCD panel, during the frame time the image is shown continuously. This type of motion blur can be reduced with a scanning backlight. We have designed and fabricated a scanning backlight system that solves the hold-type characteristic problem in a way that Flat fluorescent lamp divided 6 blocks was scanned 60Hz.

• Journal of Information Display
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• 제9권1호
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• pp.1-5
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• 2008

Two new impulsive driving technologies for 120Hz liquid crystal display (LCD) panels are proposed to improve moving picture quality. One technology generates the dark frame using an adder and a shifter simply without using any look up tables (LUTs). It results in a cost effective impulsive scheme with motion picture quality comparable to that of high speed driving. The other is a backlight flashing method designed to avoid ghost images. The issue of ghost images caused by the slow response time of liquid crystal (LC) is solved by means of 120Hz overdriving and 120Hz backlight flashing. Using the perceived blur edge time (PBET) metric, measured moving picture response time (MPRT) values were 10.8ms and 4.4ms, respectively, while that of 120Hz high speed driving was 10.1ms.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
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• pp.1153-1156
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• 2005

A backlight for large-area LCD (Liquid Crystal Display)-TVs has been developed using Light Emitting Diodes (LEDs). Performances of the backlight and the methods driving the LEDs are introduced in this research. A spectral relationship between the LEDs and the color filters of a panel were investigated as well. In order to realize a CRT like dynamic effect, the area-focused luminance control (AFLC) technology was adopted in developing the backlight. Thus, a possibility of applying the LEDs to the backlight for large-area LCD-TVs was systematically proved.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2001년도 가을 학술발표논문집 Vol.28 No.2 (2)
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• pp.538-540
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• 2001

현재 사용하는 LCD(Liquid Crystal Display) 장치는 비발광형 LCD장치를 사용하므로 외부광원이 필요하다. 투과형 LCD의 경우는 Panel의 뒷면이나 측면에 전용광원(Backlight unit)을 사용하여 빛을 투과시킴으로서 발광할 수 있도록 하는 방법을 사용한다. 현재는 이러한 투과명을 사용하는 것이 일반화되는 추세로 광원을 LCD전면으로 효율적으로 반사하는 Panel의 뒷면을 설계하는 다양한 방법이 개발되고 있다. 본 논문에서는 최적화된 설계를 위한 모델링 도구(Modeling Tool)와 주어진 광원으로부터 LCD 전면으로 출력되는 광량의 분포를 예측하는 시뮬레이터(Simulator)를 제안한다.

• 전력전자학회논문지
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• 제14권1호
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• pp.8-14
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• 2009

현재 사용하고 있는 LCD(Liquid Crystal Display) Backlight용 램프는 주로 CCFL(Cold Cathod Fluorescent Lamp)과 EEFL(External Electrode Fluorescent Lamp)이 사용되고 있다. 하지만 이 램프는 수은을 사용하여 RoHS(the Restriction of e use of certain Hazardous Substances in electrical and electronic equipment)규제가 점점 강화되면서 사용이 제한되고 있으며, 이에 따라 수은을 사용하지 않는 램프의 제작이 불가피해지고 있다. 또한 LCD TV는 CRT와 PDP와는 다른 LCD만의 Hold-type 특성과 LC(Liquid Crystal)의 응답속도로 인하여 Motion Blur현상이 나타나는 단점이 있다. 본 논문에서는 RoHS 규제를 만족시키는 무수은 면광원 램프를 구동하기 위한 인버터를 제안한다. 제안한 인버터는 포워드 방식을 사용하여 반도체 소자 및 자기 소자의 수를 줄여서 구동회로가 간단하다. 또한 면광원 램프를 세로방향으로 6블록으로 나누어 스캔구동을 하여 Motion Blur현상을 저감 시켰다. 끝으로 실험을 통하여 제안한 인버터의 유용성을 입증하였다.

• Journal of Information Display
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• 제11권2호
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• pp.45-48
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• 2010

A direct-lit liquid crystal display that does not use color filters is proposed. A backlight unit that employs compartmentalized RGB LED and lenticular-lens arrays is used instead of color filters to direct the RGB LED lights into the RGB subpixels. The color-filterless LED backlight design, simulation, and experiment results are presented.

• Journal of the Optical Society of Korea
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• 제13권1호
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• pp.152-157
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• 2009

The structure of the prism sheet and the reflective polarizer sheet in the direct - illumination liquid crystal display (LCD) backlight is optimized and fabricated. The apex angle of the prism sheet was changed from 90 degree to 96.5 and 101.5 degree and the angular spread of the diffuser films attached on the reflective polarizer sheet was changed from 7 to 1.5 degrees. The measured view angle, the normal luminance, and the contrast ratio from the optimized backlight unit showed improved optical performances.

• 전기학회논문지P
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• 제58권4호
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• pp.495-498
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• 2009

To improve the efficiency of the high voltage cable for BLU(backlight unit) of TFT-LCD(Thin Film Transistor-Liquid Crystal Display), the analysis for the trial products(UL3239, UL3633) is conducted by using SEM(scanning electron microscope) and EDX(Energy Dispersive X-ray Spectroscopy). The result that it is possible to accumulate the know-how to about stranding pitch through effective improvement of stranding process. The troubles which are the badness of withstanding voltage and tensile strength etc. are solved by development of excellent material. Furthermore, phenomenon of conductor unfasten in the harness work is solved by improvement of the stranding wire process.

• Journal of Information Display
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• 제13권4호
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• pp.167-177
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• 2012

Cold cathode fluorescent lamps (CCFLs) are used to provide lighting for liquid crystal displays (LCDs). This paper presents a set of guidelines for measurement characterization and design to reduce the power consumption of CCFL LCD backlight inverters and panel electronics. The proposed methods aim to reduce the backlight power consumption by fine-tuning a back-light inverter for a specific LCD, using several methods. First, the authors describe their power measurement methodology; and next, they identify different areas for tuning a backlight inverter for a given display. The experiment results showed that power savings can range from 50 to 200mW if the backlight inverter is properly tuned. This paper also proposes an optimized configuration for light-emitting device (LED) panels to reduce power loss by selecting a LED with a specific input voltage and number of cells to help minimize power loss.