• 소성∙가공
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• 제19권8호
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• pp.474-479
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• 2010

Newly suggested hybrid LED package can reduce the number of LED processes and enhance light efficacy in virtue of its integrated optical patterns. Square-type pyramid pattern was chosen for the integrated optical pattern in this study, and it was proved that the pattern enhances illuminance about three times and luminance about two and half times by optical simulation. Square-type pyramid patterns of 0.02mm height and 0.04mm pitch were successively machined on a copper mold which is necessary for imprinting the integrated pattern. Hybrid LED package with integrated optical pattern will be manufactured with ultra-fine machined mold in future study.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 2009년도 IWAIT
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• pp.476-481
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• 2009

In this paper, we propose a visible light road-to-vehicle communication system at intersection as one of ITS technique. In this system, the communication between vehicle and a LED traffic light is approached using LED traffic light as the transmitter, and on-vehicle high-speed camera as the receiver. The LEDs in the transmitter are emitted with 500Hz and those emitting LEDs are captured by a high-speed camera for making communication. The images from the high-speed camera are processed to get luminance value of each LED in the transmitter. For this purpose, first transmitter should be found, then it should be tracked for each frame, and the luminance value of each LED in the transmitter should be captured. In our previous work, transmitter was found by getting the subtraction of two consecutive frames. In this paper, we mainly introduce an algorithm to detect the found transmitter in consecutive frames. Experimental results using appropriate images showed the effectiveness of the proposal

• 한국수산과학회지
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• 제41권6호
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• pp.511-517
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• 2008

The radiation characteristics and economic efficiency of high - luminance light - emitting diodes (LEDs), a metal halide lamp, and a halogen lamp were studied to evaluate their potential as an energy-saving light source for fishing lamps. The wavelengths at which irradiance was maximum were 709, 613, 473, 501, 525, 465, 578, and 973 nm for red, orange, blue, peacock blue, green, and white LEDs, the metal halide lamp, and the halogen lamp, respectively. If the irradiance characteristics at 300-1,100 nm wavelengths are set as 100%, the irradiance rates at 381-780 nm were 99-78%, 82%, and 24% for the LEDs, metal halide lamp, and halogen lamp, respectively. The economic efficiency was superior in the order metal halide lamp, halogen lamp, peacock blue LED, and blue LED at 381-780 nm and metal halide lamp, peacock blue LED, blue LED, and halogen lamp at 480-520 nm. Based on the radiation characteristics and economic efficiency evaluated at 480-520 nm, the blue and peacock blue LED light sources can be used as energy-saving light sources for fishing lamps.

• 반도체디스플레이기술학회지
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• 제17권4호
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• pp.37-41
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• 2018

$Y_3A_{l5}O_{12}:Ce^{3+},Pr^{3+}$ single crystal phosphor was prepared by floating zone method. single crystal was confirmed to have a Ia-3d (230) space group of cubic structure and showed regular morphology. The optical properties, single crystal exhibited a emission band from green, yellow wide wavelength and 610nm, 640nm red wavelength vicinity. The luminance maintenance rate was decreased by phonon with increasing temperature, but high luminance is maintained more than powder phosphor. In addition, $Y_3A_{l5}O_{12}:Ce^{3+},Pr^{3+}$ single crystal phosphor was applied to a high power blue laser diode, we implemented high power white laser lightings. and it was confirmed that thermal properties over time, due to the effective heat transfer of complete crystal structure. We confirmed that excellent radiant heat properties than powder phosphor was applied to a high power white laser diode.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2009년도 제38회 동계학술대회 초록집
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• pp.92-92
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• 2010

Replacing the existing illumination with solid-state lighting devices, such as light-emitting diodes (LEDs) are expected to reduce energy consumption and environmental pollution as they provide better efficiency and longer lifetimes. Currently, white light emitting diodes are composed of UV or blue LED with down-converting materials such as highly luminescent phosphors White light-emitting diodes (LED) were fabricated with multi-shell nanocrystal quantum dots for enhanced luminance and improved stability over time. Multi-shell quantum dots (QDs) were synthesized through one pot process by using the Successive Ionic Layer Adsorption and Reaction (SILAR) method. As prepared, the multi-shell QD has cubic lattice of zinc-blend structure with semi-spherical shape with quantum yield of higher than 60 % in solution. Further, highly fluorescent multi-shell QD was deposited on the blue LED, which resulted in QD-based white LED with high luminance with excellent color rendering properties.

• 한국산학기술학회논문지
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• 제16권11호
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• pp.7256-7261
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• 2015

본 논문은 식물 재배시스템을 제작하고 LED 광원은 단색광 3개(적색, 청색, 백색), 혼합광 3개(적색1+청색1, 적색2+청색1, 적색1+청색2)를 제작하여 사용하였다. 제작한 식물 재배시스템을 이용하여 LED 광원별 광 특성, 광량의 변화에 따른 조도 및 PPFD의 특성과 식물성장을 분석하였다. 분석결과 LED 광원의 광 효율은 백색 광원이 125 lm/W로 높으며 적색1+청색2 광원은 9.9 lm/W로 낮았다. 이러한 결과로 단색광이 혼합광 보다 광효율이 좋은 것을 확인 할 수 있었다. LED의 파장별 PPFD ($25{\mu}mol$, $50{\mu}mol$, $100{\mu}mol$) 조도값 크기는 백색 LED가 높으며 청색 LED가 낮았다. 따라서 LED 광원의 다양한 단색 혼합광 파장대역 조합에 따라 식물성장에 적합한 효율적인 LED 조명 시스템을 구성할 수 있다.

• 전자공학회논문지 IE
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• 제48권4호
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• pp.25-29
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• 2011

유기 EL소자는 제작이 쉽고 휘도가 높아 CRT와 LED 대신 평판 디스플레이 패널의 광원으로써 많이 연구되어 지고 있으며, OLED 소자중 청색 OLED는 풀컬러 적용 어플리케이션에 적용할 수 있기 때문에 이에 대한 연구가 이루어 지고 있다. 본 연구에서는, 발광 소재로 PBD, Alq3를 사용하여 유기 EL 디바이스의 전기 발광 특성을 측정하였으며, 전류와 휘도는 전압과의 관계에서 알 수 있었고 휘도와 전류의 관계를 제시하였다.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2010년도 추계학술대회
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• pp.757-758
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• 2010

진료 및 수술 집도 시 조명용 광원으로 할로겐램프와 플라즈마램프가 주로 사용되고 있다. 두 광원은 램프의 수명 및 과도한 발열로 인한 다양한 문제점을 야기할 뿐 아니라 냉각기로 인하여 부피 또한 매우 크다는 단점이 있다. 따라서 본 연구에서는 의료용 신조명 부품으로 주목받고 있는 고휘도 LED를 사용하여 진료실 및 수술실에서 환자의 환부에 대한 국소 무영 촬영이 가능하도록 링라이트를 설계 개발하였다. 개발에 적용한 LED는 환부 근접 무영 촬영시 피사체 고유의 Tone에 대한 섬세한 표현력과 강한 하이라이트, 간결한 쉐도우, 그리고 입체감을 부각시키기 위하여 다양한 색상 구현과 광량 조절이 가능하고 백색광을 얻을 수 있는 FULL COLOR용 고휘도 3색 LED를 사용하였다.

• 한국수산과학회지
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• 제42권6호
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• pp.703-710
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• 2009

The spectral irradiance and underwater transmission characteristics of a combined high-luminance light-emitting diode (LED) lights have been studied to evaluate suitable light sources for fishing lamps of the next generation. The wavelengths at which the irradiance was maximum were changed from 473, 501, 525, and 465 nm for blue, peacock blue, green, and white LED light to 475, 504 and 528 nm for [$F_{WB}$], [$F_{PB}$] and [$F_{GB}$] combined LED lights, respectively. If the irradiance characteristics at 400-700 nm wavelengths are set as 100%, the irradiance rates at 450-499 nm and 500-549 nm were decreased from 82.4% and 56% for blue, peacock blue LED light to 60.0%, 38.5% for [$F_{WB}$], [$F_{WP}$] combined LED lights. The underwater transmission characteristics of the combined LED lights were superior in the order [$F_{WB}$], [$F_{BP}$], [$F_{GB}$] in optical water type I; [$F_{WB}$], [$F_{PB}$], [$F_{GP}$] in optical water type II-III; and [$F_{GP}$], [$F_{WP}$], [$F_{PB}$] in optical water type 1. Setting the 10m depth underwater transmission characteristics of the combined LED lights in optical water type I at 100%, the transmission of water types II, III and 1 drops to 29.5%, 8.0% and 2.2%. Based on the distribution of spectral irradiance and underwater transmission characteristics calculated in optical water types II-III, where was the jigging ground for fishing lamps, the [$F_{WB}]$ and [$F_{GP}$] combined LED lights can be used as a suitable light sources for fishing lamps of the next generation.

• 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.