• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.703-706
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• 2009

The external electrode fluorescent lamp(EEFL) has recently been applied to backlight of LCD TV as a new light source. The dependence of the electro-optic characteristics of the EEFL used in direct-lit backlights on the glass thickness was examined in detail, and the ultraviolet(UV)-light efficiency was estimated. It was found that the lamp efficiency became larger as the glass thickness decreased if other conditions were the same.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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• pp.578-581
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• 2007

Microplasma modes generated in a display cell with an auxiliary electrode were investigated in accordance with various coplanar-gaps and plategaps. At plate-gaps shorter than the coplanar-gap, the mode transition voltage of the auxiliary pulse increased with an increase in the coplanar-gap. At longer plate-gaps, the mode transition voltage of the auxiliary pulse decreased with an increase in the coplanar-gap.

• 전자공학회논문지B
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• 제29B권1호
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• pp.67-75
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• 1992

A new method of driving the PDP(Plasma Display Panel) was proposed and its characteristics were investigated. Applying high frequency non-discharge pulses to an auxiliary anode resulted an increased region of stable operation, decreased delay time and increased light intensity. It is suggested that PDP with DPM (Double Pulse Memory) drive technique improves the delay time, luminance, region of stable operation and luminous efficacy compared to PDP with PPM(Planar Pulse Memory) drive technique developed by NHK Lab. in Japan.

• 세라미스트
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• 제21권1호
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• pp.80-97
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• 2018

To realize a high luminous efficacy and a high emission color purity for the white-LEDs, the understanding for luminescence properties of the phosphors is significantly important because the performance of white-LEDs is directly affected by the luminescence properties of the phosphors. In this paper, therefore, we reviewed some commercially available $Eu^{2+}$- and $Ce^{3+}$- activated phosphors and discussed for the luminescence properties of these phosphors.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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• pp.7-12
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• 2006

The high efficacy concept, featuring in this study an auxiliary electrode and a 200 ${\mu}m$ coplanar gap, is applied to AC-PDPs with a stripe - type and a closed - type barrier rib, respectively. The roles of the pulses applied to the auxiliary electrode create additional excitation during the sustain period and reduce a discharge current that flows into the display cells. The efficacy of the proposed panel with the closed barrier rib has maximum values when the auxiliary pulse voltage is 50 volts and 80 volts for the Ne+4%Xe and Ne+20%Xe gas-mixtures, respectively. The maximum luminous efficacy is more than 10 lm/W in terms of the measurement of the discharges in VGA resolution ($540{\mu}m{\times}720{\mu}m$) and the green cells.

• 전기학회논문지
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• 제61권9호
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• pp.1314-1318
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• 2012

Recently, applications of plasma display to the large public display and transparent display gain much attention. With this background, we report characteristics of opposite electrodes discharge cell with long electrode gap in comparison with conventional co-planar surface discharge. The cell size of test panel is $2950{\mu}m{\times}840{\mu}m$, which corresponds to that of the display having diagonal size of 130" with XGA resolution. Electrode gap of co-planar and opposite electrode structure are $240{\mu}m$ and $500{\mu}m$ respectively. These gap dimensions provide similar driving voltage windows. Experimental results show that opposite discharge provides approximately four fold higher luminous efficacy compared with that of the surface discharge. Resulting efficacy is found to be higher than 19 lm/W in green phosphor with 10 KHz continuous pulse operation.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.1517-1522
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• 2011

Recently, application of LED luminaires has been issued for energy saving plan. In this paper, we carried out a study to replace a low efficacy sealed-beam lamp for headlight of railroad vehicles with LED luminaire. Electrical and optical characteristics of the sealed-beam lamp were analyzed and a LED headlight was designed and fabricated. Total luminous efficacy and rated power of the prototype LED headlight were 82 lm/W ; about 5 times higher, and 40W ; about 4 times lower than the sealed-beam lamp, respectively. Especially, lifetime of the sealed-beam lamp is short as 1,000 hours due to the evaporation and vibration of filament, but that of LED headlight is over 30,000 hours long.

• 전기학회논문지
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• 제61권2호
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• pp.237-242
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• 2012

In this paper, we investigated effects of ITO electrode geometry and dielectric layer thickness on the discharge Characteristic of AC PDP. As the dielectric thickness is decreased ($30{\sim}12{\mu}m$), firing and sustain voltage is decreased. Luminance and discharge power increase with decreasing dielectric layer thickness because of increasing capacitance between plasma and electrodes. Reactive power decreases with dielectric thickness due to reduced capacitance between sustain electrodes. For the high Xe test panel with small ITO electrode, luminous efficacy as well as luminance increase with decreasing dielectric layer thickness. This result suggest that high power density and small plasma volume is beneficial for high efficacy discharge.

• 전기학회논문지
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• 제58권3호
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• pp.586-590
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• 2009

Recently, an AC Plasma Display Panels(PDP) with the metal sustain electrodes have been reported in order to reduce the manufacturing cost of the AC PDP. However, the luminance and efficacy of the AC PDP with metal electrodes are worse than those of the AC PDP with ITO electrodes. In this paper, various ${\prod}$type metal electrodes are suggested, in order to improve the electro-optical characteristics of the AC PDP with metal electrodes. Among the suggested electrode types, luminance of Hump electrode structure is higher by $40\;cd/m^2$ and discharge current of Asymmetry electrode structure is lower by 5% than those of Pi electrode structure, respectively. Moreover, $T_1$ of Hump electrode structure is reduced to 10% as compared with Pi electrode structure in address period for ADS driving scheme. In all aspects, the characteristics of Hump and Asymmetry electrode structure show best performance.

• 전기학회논문지
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• 제56권7호
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• pp.1261-1267
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• 2007

Although LEDs have been used in various applications with improving the brightness and luminous efficacy, the electrical and optical characteristics of high power LED varies at different temperature and starting time. In this paper, optimal heat sink and apparatus design were conducted using IR camera and ICEPAK on the LED bulb consisting with fourteen LED array. The temperatures of heat sink and LED device of the designed LED bulb without cooling pan were $74^{\circ}C\;and\;96.8^{\circ}C$, respectively, showing in good themal characteristics. For high efficiency driving circuit of LED array adopted optimal heat sink design, driving circuits of constant voltage and current circuits were suggested and fabricated. As a result the efficacy of all driving circuits showed more than 20 lm/W. Also, the constant current circuits are suitable for signal lamp, hallway lamp, and flash lamp having short operating time(about 30 min). On the other hand, a reading light and indoor lamp having long operating time can be controlled by constant voltage circuit.