• 한국전자파학회논문지
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• 제21권3호
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• pp.285-291
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• 2010

본 논문에서는 조명용 LED와 솔라 셀을 사용하여 실내 무선광 통신이 가능함을 보인다. 조명용 LED를 광원으로 사용하면 조명과 신호의 송신을 겸할 수 있으며, 솔라 셀을 수광 소자로 이용하면 조명광을 수신하여 에너지를 축적하는 동시에 신호를 검출할 수 있기 때문에 별도의 통신 시설을 설치하지 않고 전송이 가능하여 매우 편리하다. 실험에서는 조명용 LED와 솔라 셀을 사용하여 9.6 kbps 속도로 무선광 데이터 전송을 실시하였다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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• pp.557-560
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• 2008

The main goal of this work is to fabricate light emitting diode (LED) module and apply it to mobile handset. We first fabricated the blue-color LED based on the AlInGaN cell structure with size of $200\;{\mu}m\;{\times}\;200\;{\mu}m$. Also we proposed a new $1.0\;mm\;{\times}\;0.5\;mm$ (1005size) packaging procedure for the LED cell. Thus the overall dimension of our LED cell was as small as $1.0\;mm\;{\times}\;0.5\;mm\;{\times}\;0.4\;mm$ ($W\;{\times}\;L\;{\times}\;T$). As far as we knew it was the first time that this small LED cell dimension had been fabricated and operated.

• 한국산학기술학회논문지
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• 제21권11호
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• pp.70-77
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• 2020

미세조류는 광합성을 수행하는 독립영양생물로 배양 환경을 변화시켜 미세조류 유래 유용물질의 축적을 증대시킬 수 있다. 본 연구에서는 미세조류 S. obliquus의 세포 성장에 주요 인자인 배지와 광원의 영향을 평가하기 위해 MBBM, Neo 배지와 7가지의 광원을 사용하여 39일 동안 배양하여 세포 성장을 측정하였다. 그 결과 MBBM과 Neo 배지에서 성장한 S. obliquus의 경우, Fluorescent light 광원과 Red2 LED (R660) 광원에서 세포 성장이 가장 높게 관찰되었고, Infra Red LED (R741) 광원에서는 세포 성장이 가장 낮게 관찰되었다. 평균 세포 성장률은 MBBM 배지에서 17.7 %, Neo 배지에서 15.4 %의 성장률을 확인하였다. MBBM과 수생식물 생산용 영양소를 포함한 Neo 배지의 건조세포무게(dry cell weight)를 비교하였을 때, Blue LED (B450)를 제외한 LED 광원에서 Neo보다 많은 세포 성장이 높은 것이 확인되었다. 이는, MBBM 배지가 Neo 배지보다 미세조류 세포량 증대에 보다 적합함이 증명되어 향후 미세조류 대량배양을 통한 유용물질 생산에 있어 광원 선정이 중요하다는 것이 확인되었다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제33권1호
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• pp.1-10
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• 2007

To verify the inhibitory or protective effects of light-emitting diode(LED) irradiation on apoptotic cell death induced by $CoCl_2$, human SH-SY5Y cells were treated with $CoCl_2$ and LED were used to irradiate the cells. In the cell viability assay, cells were died slowly from $50{\mu}M$ to $250{\mu}M$ and about 50% of cells died after 12 hours at $400{\mu}M$ of $CoCl_2$. The Diff-Quik staining revealed that cells showed condensation of DNA and blebbing of the cell membrane. The DNA fragmentation assay revealed the DNA fragmentation, which is another apoptosis marker, occurred in cells treated with $400{\mu}M$ $CoCl_2$ for 16 hours. In the western blot for HIF-$1{\alpha}$, HIF-$1{\alpha}$ was expressed after 3 hours from induction and peaked maximally at 16 hours. In the cell viability assay of the effects of LED irradiation (at 590 nm for 1 hour 20 minutes), the cells showed more proliferation (about 20%) than the control group. The RPA assay of various apoptosis-related molecules showed that pro-apoptosis molecules such as Bax, Bak, and Bid were upregulated in the $CoCl_2$ treatment group. This means that the apoptotic cell population was increased. However there was some significant changes in LED irradiated cells. In the $CoCl_2$-treated LED irradiation group, those molecules were down-regulated more than in the only $CoCl_2$-treated group. These results have shown that $CoCl_2$ may induce apoptotic cell death in human SH-SY5Y neuroblastoma cells. And LED irradiation has a positive effect on apoptotic cells by down-regulation of pro-apoptotic molecules.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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• pp.512-513
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• 2008

The study examined what effects 100kHz PWM LED light irradiation causes to bone marrow cells of SD-Rat when LED characterized cheap and safe is used onto the light therapy by replacing the low 1evel laser. We developed the equipment palpating cell proliferation using a high brightness LED. This equipment was fabricated using a micro-controller and a high brightness LED, and designed to enable us to control light irradiation time, intensity, frequency and so on. Especially, to control the light irradiation frequency, FPGA was used, and to control the change of output value, TLC5941 was used. Consequent1y, the current value could be controlled by the change of 1eve1 in Continue Wave(CW) and Pulse Width Modulation(PWM), and the output of a high brightness LED could be controlled stage by stage. MTT assay method was chosen to verify the cell increase of two groups and the effect of irradiation on cell proliferation was examined by measuring 590nm transmittance of ELISA reader. As a result, the cell increase of Rat bone marrow cells was verified in 100kHz PWM LED light irradiation group as compared to non-irradiation group.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2008년도 춘계학술대회 논문집
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• pp.107-112
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• 2008

Solar Cell을 이용한 15W 휴대용 조명 시스템을 개발하기 위하여, 휴대용에 적합한 solar cell을 선정하고, Solar Cell을 충전하기 위한 태양광 궤적 변화에 대한 Simulation을 행하였으며, 1W 백색 LED 6EA를 사용하여 휴대용 LED Lighting System을 개발하였다. LED Lighting System은 solar cell 충방전 회로 및 LED SMPS 구동회로 설계, 글레어차단을 위한 리플렉터 설계, 방열 설계 및 기구 구조 설계를 통하여 개발되었으며, 직접 시제품을 제작하고 그 성능을 측정하였다.

• 신재생에너지
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• 제5권4호
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• pp.34-37
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• 2009

Using six SMD(surface mount device) type AlGaAs/GaAs single junction solar cells connected in series, a power source was fabricated for a white GaN LED. The electrical properties of the power source was measured and analyzed under one sun (100mW/$cm^2$) and various indoor light (300 - 900 lux) conditions. Under 600 lux indoor light condition, output power was 17.06 ${\mu}W$ and it was 30.75 ${\mu}W$ under 900 lux indoor light condition. Using the fabricated solar cell power supply, we have turned on the white GaN LED. It was worked well under 15 ${\mu}W$(at 480 lux) power supplied from solar cell array. This kind of solar cell power supply can be used as a power source for ubiquitous sensor network (USN).

• 한국전기전자재료학회논문지
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• 제19권12호
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• pp.1149-1153
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• 2006

We developed the equipment palpating cell proliferation using a high brightness LED. This equipment was fabricated using a micro-controller and a high brightness LED, and designed to enable us to control light irradiation time, intensity, frequency and so on. Especially, to control the light irradiation frequency, FPGA was used, and to control the change of output value, TLC5941 was used. Control stage is divided into 30 levels by program. Consequently, the current value could be controlled by the change of level in Continue Wave(CW) and Pulse Width Modulation(PWM), and the output of a high brightness LED could be controlled stage by stage.

• 대한임상검사과학회지
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• 제49권2호
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• pp.150-160
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• 2017

아토피피부염은 만성 염증성 피부질환으로 습진성병변, 피부건조 및 가려움증의 특징적 증상을 보이는 질환이다. 현재 사용되고 있는 아토피피부염 치료약제들은 오래 사용시 여러 부작용이 있어서 이를 대신할 새로운 대체 치료법의 개발이 요구되고 있다. Curcumin은 항염, 항알러지와 같은 효과를 나타내는 천연 폴리페놀(polyphenol)이며, 발광다이오드(light emitting diode, LED) 광치료는 아토피피부염과 상처치유에 효과가 있는 것으로 알려져 있다. 본 연구는 DNCB로 유도한BALB/c 마우스의 아토피피부염에서 curcumin 투여와 630 nm LED 조사를 병용하여 그 치료 효과를 높일 수 있는가를 조사하기 위해 시도하였다. 아토피피부염의 치료 효과를 조사하기 위해 modified SCORAD 지수, 조직병리학적 분석, 면역조직화학염색 및 TUNEL 검사를 사용하였다. 그 결과 curcumin 투여와 630 nm LED 조사가 각각 SCORAD 지수, 비만세포 및 탈과립세포의 수, 호산구 수, 표피세포의 증식능 및 자멸세포의 수를 의미 있게 감소시키고, 비만세포의 탈과립을 억제하여 섬유모세포에 의한 콜라겐 생성을 의미 있게 감소시켰으며, curcumin 투여와 LED 조사를 병용하였을 경우 단일 처리군에 비해 이들 수치가 의미 있게 감소하는 것을 확인하였다. 이러한 결과는 아토피피부염 치료에 curcumin 투여와 LED 조사가 각각 효과가 있음을 의미하며, 병용 치료 시 그 효과가 좀 더 향상된다는 것을 의미하는 것으로, 아토피피부염의 대체치료 전략으로 curcumin 투여와 630 nm 조사의 병용 치료를 제안한다.

• 센서학회지
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• 제24권4호
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• pp.232-238
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• 2015

In this paper, we introduce a passive transponder in which an LED is used for both a light transmitter and a receiver, and a solar cell is used for supplying power to the all devices in the transponder. The LED in the transponder operates as a photodetector in the receiving mode, and acts as a light source in the transmitting mode. The current responsivity of the LED detector was measured to be in the order of $10^{-4}A/W$, and the receiving bandwidth with a load resistance of $10k{\Omega}$ was about 10 to 30 kHz. Using the LED for an optical transceiver in a VLID transponder, the detection range was about 70 cm when the transponder was illuminated by the visible light from a $3{\times}3$ LED array in a reader.