• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.1347-1348
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• 2008

The efficacy and its degradation of light emitting diode(LED) are related to its PN junction's temperature(Tj). Currently efficacy in certain temperature and thermo-resistant are defined for the depending. However, the definitions are quite inconvenient for lighting application. The paper focuses on the issue and presents a method to evaluate the thermal characteristics of LED efficay.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.779-780
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• 2009

New inverted architecture of a hybrid inorganic-organic light-emitting diode, utilizing ZrO2 electron-injecting layer, is presented. The thickness of the ZrO2, as well as the annealing of the light-emitting polymer, is found critical to obtain good performance. A range of light-emitting polymers is shown to operate efficiently in the proposed architecture.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.5
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• pp.571-574
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• 2013

To determine an efficient growth system for algal cultivation and to develop adequate culture system utilizing LED light, we investigated the effects of fluorescent and light emitting diode (LED) light source on the growth of Ulva pertusa. U. pertusa was cultured at $17^{\circ}C$ under a light intensity of 35 ${\mu}mol$ photons $m^{-2}s^{-1}$ and a 10L:14D photoperiod using either fluorescent or LED lamps. After 1 week of incubation under the same environmental condition, the length and width of Ulva pertusa grown under LED light were 1.5- and 1.9-fold greater, respectively, than the length and width of algae grown under fluorescent light. After two weeks, length and width were 2.6- and 2.0-fold greater, respectively, in algae grown under LED light. Total length and width of Ulva pertusa after three weeks of incubation were 1.7- and 1.2-fold greater in algae grown under LED light than those grown under fluorescent light. Therefore, the LED light induced significantly higher growth of Ulva pertusa than fluorescent light.

• 제어로봇시스템학회:학술대회논문집
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• 1991.10b
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• pp.1956-1960
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• 1991

This paper describes the measured results upon monochromatic light, compound light, and light emanated from light emitting diodes by a simplified wavemeter with a semiconductor color sensor. Since a single unit element of a semiconductor color sensor with two PN junction photodiodes has been developed, the author has fabricated the simplified wave detector by using the element. The simplified wive detector has been measured results upon monochromatic light, compound light, and light emanated from light emitting diodes. Since luminescent color of each diode locates in luminosity region, comparison of measured values of PD-150 and PD-151 resulted no remarkable difference in averaged wave length. As for monochromatic light, PD-151 showed very cross value to the color filter peak value rather than PD-150. As for compound light, PD-150 has shown such influence of long wave length light which reaches to near infrared ray with respect to PD-151.

• Medical Lasers
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• v.8 no.2
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• pp.94-96
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• 2019

Burns are one of the most extensive injuries of soft tissues as well as skin, occasionally resulting in extensive, deep wounds and death. Burn wounds can lead to severe physical and psychological distress because of excessive scarring and skin contractures. Treatment of burn wounds has always been a challenging problem and many different methods have been used to treat such injuries. We report here on treating a patient with a burn wound using 830-nm light emitting diode (LED) phototherapy combined with epidermal growth factor (EGF) solution. After five daily sessions of LED with EGF solution treatment, the patient demonstrated nearly complete improvement with no remarkable side effects. We suggest that LED phototherapy combined with EGF solution could be an effective and safe treatment option for treating burn wounds.

• Journal of Applied Biological Chemistry
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• v.57 no.3
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• pp.255-257
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• 2014

This study was conducted to determine the attractive effects of Plutella xylostella adults to light emitting diode (LED) trap in greenhouse and compared with those of no light trap and black-light which is typically used in commercial luring lamp. The green LED trap captured more P. xylostella when compared with black-light trap, whereas the no light trap was a little attractive to P. xylostella adults. These results indicated that the green LED traps could be used for environmental insect pest control.

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.762-765
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• 2002

The bilayer organic light-emitting diode using Al (DBM) $_3$ (DBM=Dibenzoylmethane) as an emitting material and poly (N-vinylcarbazole) (PVK) as hole-transport material, emitted bright blue-green light instead of blue light. The blue-green emission is attributed to exciplex formation at the solid interface between Al (DBM) $_3$ and the hole-transport material. The exciplex formation was evidenced by the measurement of the photoluminescence spectra and lifetimes of Al (DBM) $_3$, PVK and an equimolar amount of mixture of Al (DBM) $_3$ and PVK.

• Journal of Satellite, Information and Communications
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• v.8 no.1
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• pp.71-76
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• 2013

In this paper, a transceiver of VLC (Visible Light Communication) using LED white lighting has been implemented. The transmitted waveforms of LED and PD (Photo Diode) of the received signal are analyze to restore VLC data. Audio signal was successfully transmitted to demonstrate possibility and potential of optical wireless communication systems. Various modulation formats are considered to evaluate and compare performance in diverse channel conditions.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.9
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• pp.630-636
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• 2012

The purpose of this study was to determine optimum wavelength, light intensity, aeration rate, and temperature for the cultivation of Dunaliella salina illuminated by various types of light emitting diode. Growth rates of Dunaliella salina were faster at higher temperature than the growth rate at lower temperature. Among the culturing temperatures, $22^{\circ}C$ was the optimum temperature for the growth of Dunaliella salina. White LED was the most efficient light source and lower light intensity (3,000 Lux) resulted in better biomass production (1.30 g/L). The value of aeration varied between 0 and 2.4 vvm at the illumination of 3,000 Lux of white light emitting diode. Highest specific growth rate of $1.12day^{-1}$ was obtained at no-aeration and lower specific growth rates were obtained for other aeration tests, which indicated that aeration could be harmful for the cultivation of Dunaliella salina.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.1148-1151
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• 2009

A self-designed, written in labview, Organic Light-Emitting Diode junction temperature measuring program was used to calculate the internal junction temperature for devices during operation, and an infrared thermometer was used to measure the backside temperature of the device substrate, to discuss the effects of the junction and substrate temperature difference to the characteristics of the device.