• Transactions on Electrical and Electronic Materials
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• 제8권2호
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• pp.93-96
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• 2007

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 1 W high power of the lumileds company. We could know that this backlight unit releases to 6500 nit in 14 W power consumption and start up voltage time is under the 15ms in the ambient temperature $-20\;^{\circ}C$.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2007년도 하계학술대회 논문집
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• pp.244-246
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• 2007

The LCD backlight technique using light-emitting diode(LED) has been studied in the recent backlight market. The white light is need for LCD backlight and it is generally implemented by combining the RGB-LEDs to obtain the high brightness. However, RGB-LEDs have different color characteristics for the current and temperature variations, which results in the color shift problem. The color shift characteristics of RGB-LEDs for the current and temperature variations are investigated in this paper. This result can be used to control the color of backlight system using RGB-LEDs.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 추계학술대회 논문집
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• pp.377-378
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• 2007

In this paper, we were confirmed the optical characteristics of LED module by changing ambient temperature and driving current. When we supplied same driving current, the brightness quality drops due to an increased ambient temperature. The difference of brightness properties came out more large according to an increased driving current. Moreover, peak wavelength become shifted by long wavelength and declined output power by increasing driving current.

• 한국세라믹학회지
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• 제49권1호
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• pp.105-110
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• 2012

In this paper, a yellow phosphor $Sr_3SiO_5:Eu^{2+}$ that emits efficiently at the 450 nm excitation for warm white LED is studied. In addition, the effects of various flux $BaF_2$, $NH_4Cl$ on the emission spectra were investigated. The samples were synthesized through conventional solid state reaction under reducing atmosphere of 95% $N_2$-5% $H_2$ mixture at the high temperature. All phosphors showed a excitation band from 450 nm and broad band emission peaking at region of 580 nm. The optimal concentration of $BaF_2$ flux is 3 wt% for $Sr_3SiO_5$ with doping 0.05mol Eu phosphors fired in a reductive atmosphere. The phosphor showed highest emission peaking at 582 nm.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2002년도 International Meeting on Information Display
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• pp.736-739
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• 2002

We report on white light emission from a light emitting diode(LED) prepared by blending a red emitting copolymer, m-SiPh PPV-co-MEH PPV, and a blue emitting polyvinylcarbazole (PVK). White light emission was realized when the weight ratio of the m-SiPh PPV-co-MEH PPV : PVK equals to 1 : 30, in which the commission Internationale de L'Eclairage coordinates were x=0.3266 and y=0.3438.

• 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.

• Journal of Microbiology and Biotechnology
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• 제29권12호
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• pp.1957-1968
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• 2019

Tetraselmis is a green algal genus, some of whose species are important in aquaculture as well as biotechnology. In algal culture, fluorescent lamps, traditional light source for culturing algae, are now being replaced by a cost-effective light-emitting diodes (LEDs). In this study, we investigated the effect of LED light of different wavelengths (white, red, yellow, and blue) on the growth of Tetraselmis suecica and its associated microbial community structures using the next-generation sequencing (NGS). The fastest growth rate of T. suecica was shown in the red light, whereas the slowest was in yellow. The highest OTUs (3426) were identified on day 0, whereas the lowest ones (308) were found on day 15 under red light. The top 100 OTUs associated with day 0 and day 5 cultures of T. suecica under the red and yellow LED were compared. Only 26 OTUs were commonly identified among four samples. The highest numbers of unique OTUs were identified at day 0, indicating the high degree of initial microbial diversity of the T. suecica inoculum. The red light-unique OTUs occupied 34.98%, whereas the yellow-specific OTUs accounted for only 2.2%. This result suggested a higher degree of interaction in T. suecica culture under the red light, where stronger photosynthesis occurs. Apparently, the microbial community associated with T. suecica related to the oxygen produced by algal photosynthesis. This result may expand our knowledge about the algae-bacteria consortia, which would be useful for various biotechnological applications including wastewater treatment, bioremediation, and sustainable aquaculture.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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• pp.368-369
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• 2003

The recent development of InGaN-based white light emitting diodes (LEDs) has expanded their potential applications in areas such as white electric home appliances, backlight for mobile phone or notebook PC, and indoor lightings. In this lecture, recent researches related to the phosphors for LEDs applications and their luminescent properties were reviewed. PDPs are considered as the most potential flat panel displays with a large-screen size. Phosphors in PDPs directly affect the brightness and lifetime. So, many researchers have tried to improve the luminescence characteristics of the phosphors especially under vacuum ultraviolet (VUV) excitation. We overviewed recent research trends and conclusive achievements for the PDP phosphors.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.1216-1219
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• 2009

Recently,electroluminescence devices based on organic semiconductors have made considerable progress. Displays based on organic light emitting diodes (OLED) are commercially available. To gain broader acceptance, the performance of OLED devices has to be further improved, in particular for lighting. This article discusses the possibility to use controlled electrical doping for improving the properties of devices and new approaches for highly efficient white OLED.

• 원예과학기술지
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• 제30권6호
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• pp.673-679
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• 2012

본 실험은 밀폐형 식물생산시스템에서 인공광원과 광조사 시간에 따른 잎상추 '선홍적축면' 품종의 적정 생육 조건을 구명하고자 수행하였다. 상추 유묘를 3종류의 인공광원인 형광등과 에프씨 포이베(사)와 헤파스(사)의 백색 LED 아래에서 재배하였고, 광조사 시간을 각각 12/12, 18/6, 24/0(명기/암기)으로 처리하였다. 광파장대를 측정한 결과 형광등은 400-700nm 범위에서 다양한 피크를 나타냈지만, 2종류의 백색 LED에서는 450nm와 550nm의 파장대역에서만 피크를 나타냈다. 초장, 생체중 및 건물중은 광조사 시간을 24/0(명기/암기)으로 처리하였을 때 가장 우수했다. 또한 엽면적도 광조사 시간 24/0(명기/암기) 처리구에서 좋았다. 형광등 처리가 2종류의 백색 LED와 비교하여 최대근장, 엽수, 생체중 및 총 안토시아닌 함량이 우수하였다. 엽록소 형광값은 형광등을 사용하여 광조사 시간을 12/12(명기/암기)로 처리하였을 때 가장 높았다. 형광등 광원에서 광 에너지 사용 효율은 LED 등이 형광등과 비교하여 약 35-46% 더 높았다. 본 결과는 식물공장 시스템에서 상추 재배를 위한 형광등의 대체 광원으로써 LED의 이용가능성을 보여 주었다.