• 한국광학회:학술대회논문집
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• 한국광학회 2002년도 제13회 정기총회 및 2002년도 동계학술발표회
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• pp.170-171
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• 2002

• 한국광학회:학술대회논문집
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• 한국광학회 2002년도 제13회 정기총회 및 2002년도 동계학술발표회
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• pp.138-139
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• 2002

• 한국광학회:학술대회논문집
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• 한국광학회 2002년도 제13회 정기총회 및 2002년도 동계학술발표회
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• pp.180-181
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• 2002

• 한국광학회:학술대회논문집
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• 한국광학회 2002년도 제13회 정기총회 및 2002년도 동계학술발표회
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• pp.44-45
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• 2002

• 한국전기전자재료학회논문지
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• 제23권8호
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• pp.638-644
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• 2010

We have carry out numerical simulation of the electric-optical characteristics of organic light emitting diodes with gradient-doped emitting layer which were reported to be effective in improving luminous efficiency and lifetime. In this paper, the basic structure is comprised of ITO/NPB/$Alq_3$:C545T[%]/$Alq_3$/LiF/Al, six devices by separating the emitting layer of $Alq_3$:C545T[%] were studied. As the result, the uniformly-doped devices exhibited superior luminous efficiency-current density characteristics over conventional undoped device. In the case of gradient-doped devices, electric-optical characteristics were improved similar to uniformed-doped devices, unusually the distribution of traped-charge density in the OLED devices was shown as the staircase.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 하계학술대회 논문집
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• pp.369-372
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• 2001

We studied the electro-optical (EO) performance in the vertical-alignment (VA) - l/4$\pi$ cell photoaligned with polarized UV exposure on a homeotropic photopolymer surfaces. Excellent voltage-transmittance curve in the VA - l/4$\pi$ cell photoaligned with polarized UV exposure for 3 min on the photopolymer containing cholesterol group of 8% can be achieved. The V-T characteristics in the VA-l/4$\pi$ cell photoaligned on the photopolymer surface can be improved by increasing cholesteryl group. For response time measurement, the transmittance characteristics of the VA-l/4$\pi$ cell photoaligned on the photopolymer surface was better than that of the VA-l/4$\pi$ cell rubbingaligned on a polyimide(Pl) surface.

• 보존과학회지
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• 제5권1호
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• pp.11-19
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• 1996

This research carried out on characteristics of degradation for the handmade Japanese paper(Washi) and handmade Korean paper(Hanji), which are not studied clearly at present, made an experiment on the physical and the optical tests to the temperature and humidity, The results are as follows ;The handmade Korean paper showed worse results of physical and optical tests than those of Washi. Above all, that low durability was the most characteristics. The handmade paper demands preservation, and therefore, the fiber selection of compositive materials is important. For the handmade Korean paper showed this time, put waste pulps off, and adjust the mixing maintaining appropriate basis weight, and then it must be improved durability.

• 한국전기전자재료학회논문지
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• 제14권8호
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• pp.670-674
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• 2001

The electro-optical (EO) performance in the vertical-alignment (VA) - 1/4$\pi$ cell photoaligned with polarized UV exposure on a homeotropic photopolymer surfaces was investigated. Excellent voltage-transmittance curve in the VA - 1/4$\pi$ cell photoaligned with polarized UV exposure for 3 min on the photopolymer containing cholesteryl group of 8% can be achieved. The V-T characteristics in the VA-1/4$\pi$ cell photoaligned on the photopolymer surface can be improved by increasing cholesteryl group. For response time measurement, the transmittance characteristics of the VA-1/4$\pi$ cell photopolymer surface was better than that of the VA-1/4$\pi$ cell rubbingaligned on a polyimide(PI) surface.

• Journal of the Optical Society of Korea
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• 제10권2호
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• pp.86-90
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• 2006

The external feedback effect on the relative intensity noise (RIN) characteristics of blue InAlGaN laser diode has been analyzed taking into account the spontaneous emission noise and the injection current for the high frequency modulation. A Langevin diffusion model was exploited to characterize its relative intensity noise. The simulation parameters were quantitatively evaluated from the optical gain properties of the InAlGaN multiple quantum well active regions by using the multiband Hamiltonian for the strained wurtzite crystals. The extracted parameters were then applied to the rate equations taking into account the external feedback and the high frequency modulation current. The RIN characteristics were investigated to optimize the low frequency laser diode noise characteristics.

• 한국정보전자통신기술학회논문지
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• 제10권6호
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• pp.477-486
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• 2017

무전극 램프의 광학적 특성 분석을 위한 연구에서는 램프 표면의 온도를 모두 동일하게 취급해 왔었다. 그러나 이러한 방법에 의해 광학적 특성을 해석하는 것은 정확도를 고려할 때 충분하지 않은 문제점을 가지고 있었다. 본 논문에서는 이러한 문제를 극복하고자 벌브 내부를 열점과 냉점의 두 부분으로 나누어 서로 다른 온도에 의한 수은의 밀도차이를 분석하였다. 여기서는 온도와 밀도의 분포가 선형적임을 가정하였다. 열점과 냉점의 밀도의 재분배를 통한 광 특성의 영향을 분석하였다. 또한, 재분배된 방전기체 간의 밀도의 비가 광 특성의 포화에 지대한 영향을 미치고 있음도 확인하였다. 따라서 가정을 통한 설계 방법이 실제의 설계에서 매우 유용함을 입증하였으며, 또한 광 특성이 안정되는 시간을 단축하는 방법에 대한 성과도 확보하였다. 이러한 결과를 토대로 원통형 무전극 방전램프의 효율적인 설계의 한 방안을 제시하였다.