• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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• pp.1045-1048
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• 2007

We mainly report recent progress in backlight unit (BLU) for liquid crystal display (LCD) using printed carbon nanotubes (CNTs) including top-gate and lateral gate structures. Lighting performances of CNTBLU and longevity of printed CNT emitters are intensively discussed. Selected issues related with field emission display (FED) using the same emitters also are presented.

• 전기학회논문지
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• 제56권7호
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• pp.1275-1281
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• 2007

The discharge phenomena in a flat fluorescent lamp for the backlight unit of liquid crystal displays are simulated by sung a two-dimensional fluid model. The numerical methods for the calculation of plasma dynamics and the radiation transport are introduced for the discharge simulation and for the transmission of the vacuum ultraviolet lights. The simulation results are presented to compare the luminance and the luminance efficacy with the variation of gas pressure, gas mixture ratio, driving voltage, and frequency.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
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• pp.1507-1509
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• 2005

LCD(Liquid Crystal Display) products is needed to have high reliability and are produced without harmful material. Because Substitution for CCFL of Light source used to Conventional backlight unit, research is going about product with LED of light source at present. In this experiment, We made the LED backlight unit with high quality for automotivenavigation. This backlight unit has center luminance of 6500 nit at15W power consumption. We adjusted chromaticity by using ten Blue LED and eight side emitting type White LEDs with high power LED from Lumileds company.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.1440-1443
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• 2009

We have devised a methodology based on the concept of foveal (or parafoveal) vision to investigate viewing angle related mura of a backlight unit (BLU). Three different cases of mura phenomenon in BLUs are studied with optical simulation software ASAP in this work. Simulation results, illuminance comparisons between emitting light from BLUs without and with "angle sorting" as well as experimental results are presented. They show good agreement between simulations and experimental observations that demonstrates the method's validation and robustness.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.229-230
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• 2009

This paper proposes a new design of ultra-slim color mixing lens (CML) for backlight unit (BLU), and presents simulated performance of the design. The novel color mixing structure has a shorter mixing length (< 1cm) than the existing color mixing structure, and achieves high efficiency and uniformity.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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• pp.150-155
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• 2006

Carbon nanotubes backlight unit (CNT-BLU) that lightened by field emission was developed into practicability. According to our novel structure, AC mode circuit design and simple printing process, CNT-BLU could achieve 85% of uniformity, 8000 nits of brightness and low material and fabrication cost. Based on these performances, this new planar backlight technology has chances to proceed to mass production and has the potential to replace traditional backlight technology because of its good properties, like the simple processes, easy to large scale, low surface temperature, low power consumption, optical film-free and Hg-free, etc.

• 한국산학기술학회논문지
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• 제21권12호
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• pp.702-708
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• 2020

최근 LED 디스플레이 시스템의 대형화에 따라서 시스템의 효과적인 전력 제어 방법에 대한 연구가 진행 중이다. 그 중에서 본 논문에서는 BLU(Backlight unit)시스템의 채널 별 LED 특성차에 기인한 전력 손실을 최소화하기 위한 전력 제어 방법을 제안하였다. 제안된 전력 제어 기능을 갖는 LED 드라이버 IC는 전 채널의 정전류 동작이 가능한 최소 headroom 전압을 검출 후 DC-DC 컨버터 출력을 선형적으로 제어하여, 불필요한 추가 전압에 따른 전력 소모를 최소화 할 수 있도록 하였다. 또한 채널 별 전압 감지 비교기와 기준 전압 생성 회로가 필요하지 않아서 집적 회로 구현시 칩사이즈 감소 및 안정화 측면에서 큰 장점을 갖는다. 제안된 전력 제어 기능 동작을 검증하기 위해서, DC-DC 내장형 전력제어 LED driver IC를 Cadence 및 Synopsys사의 Design Tool을 사용하여 설계하였으며, Magnachip 0.35um 5V/40V CMOS 공정을 사용하여 제작하였다. 제작된 IC실험을 통해서 제안된 전력 제어 방법이 BLU시스템의 최소 필요 전압을 정상적으로 제어함을 확인하였다.

• 한국광학회지
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• 제21권6호
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• pp.247-253
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• 2010

본 논문에서는 에지 방식의 BLU(Backlight unit)에 사용되는 도광판의 구조를 최적화하여 광학시트를 줄이면서 휘도와 균일도 및 시야각을 유지하기 위한 이중구조의 도광판을 설계하고 시뮬레이션을 통해 휘도와 균일도를 알아보았다. 여기에 사용된 복합 도광판은 이중구조의 도광판으로 상부에는 곡률 R을 갖는 프리즘패턴을 형성하고 곡률 R에 따른 휘도와 균일도를 시뮬레이션하였다. 하부에는 V groove 패턴을 회전시켜 상부패턴과 $90^{\circ}$를 이루게 하여 균일도를 확보하였다. 특히, 하부 패턴에서는 외곽의 피치 간격과 중심의 피치간격의 비(최대:최소), 패턴의 개수와 패턴의 분산을 정의할 수 있는 프로그램을 설계하여 V groove 사이의 간격을 결정하였다. 복합 도광판(dual-layer light guide plate, DLGP)의 최적화를 위해 다시 하부 패턴의 개수를 변화시켜 균일도를 알아보았다. 시뮬레이션 결과 복합 도광판을 이용한 BLU는 균일도 90.6%, 시야각 $145^{\circ}$인 특성을 갖는 것을 확인하였다.

• Journal of Information Display
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• 제11권2호
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• pp.39-44
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• 2010

The time dependences of the luminance properties of 55-inch CCFL and LED backlights and 32-inch FFL backlights with LCD panels were investigated during the warm-up time from the cold start. The long-term luminance maintenance curve of a standard CCFL was examined in a time window up to 5000 hours. These two time dependences are important characteristics from the viewpoint of initial picture quality and lifetime reliability, respectively. Empirical equations were suggested for the analysis of the time dependence of these luminance data. These approaches are expected to be helpful in predicting the luminance properties of backlights based on the luminance data obtained in a limited time window.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 하계학술대회 논문집 Vol.7
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• pp.414-415
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• 2006

At present, Characteristic of high color reproduction for LCD products needed in Display market. Therefore, The improving methods of high color reproduction are alteration of color Filter or Red, Green, Blue phosphor alteration of CCFL. But High color reproduction phosphor is short life time as compared with conventional phosphor. In this experiment, by using split the Red, Green, Blue CCFL with high color reproduction phosphor instead of conventional high color reproduction CCFL. We knew that the high color reproduction RGB split CCFL BLU has same spectrum data and chromaticity, but has long life time as manufacturing RGB split CCFL and reduce chromaticity shift following long time discharge as compared with conventional high color reproduction CCFL.