• 한국군사과학기술학회지
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• 제17권1호
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• pp.82-89
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• 2014

The damage in germanium (Ge) optical window irradiated by a near-infrared continuous wave (CW) laser was studied. Laser-induced heating and melting process were surveyed, and the specific laser power and the irradiance time to melt were estimated by numerical simulation. The experiments were also carried out to investigate the macro and micro structure change on Ge window. Results showed that the surface deformation was formed by melting and resolidification process, the damaged surface had a polycrystalline phase, and the transmittance as an optical performance factor in mid-infrared region was decreased. We confirmed that an abnormal polycrystalline phase and surface deformation effect such as hillock formation and roughness increase reduced the transmittance of Ge window and were the damage mechanism of CW laser induced damage on Ge window.

• 한국안광학회지
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• 제16권3호
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• pp.219-228
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• 2011

목적: 안경원의 쇼윈도 디스플레이 유형에 따른 소비자 집단의 감성 의미를 객관적으로 분석하여 마케팅에 적합한 디스플레이 유형을 도출하는 것을 목적으로 하였다. 대상 및 방법: 서울지역 안경광학과 재학생 집단을 대상으로 연구를 실시하였다. 국내 안경원의 쇼윈도 디스플레이 예제들을 수집하여 대표적 유형을 도출하였다. 의미분별 척도법을 이용하여 감성 의미를 추출한 후에, 설문조사와 통계처리를 통하여 각각의 디스플레이 유형별로 해당되는 감성 의미를 결정하였다. 결과: 설문응답자들은 개방형, 소량형, 대량형 및 광고형의 4가지 대표적 쇼윈도 디스플레이 유형별로 각각 깨끗하고 심플함, 고급스럽고 심플함, 서민적이고 실용적이라는 감성 의미를 주로 선택하였다. 결론: 도출된 감성 의미들과 응답자들의 선호도를 분석했을 때, 대학생 집단에게 가장 적합한 디스플레이 유형은 소량형인 것으로 여겨진다.

• 한국광학회:학술대회논문집
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• 한국광학회 2008년도 하계학술발표회 논문집
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• pp.353-354
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• 2008

in the environment with high temperature and humidity, surface temperature of the display window should be increased more than the temperature of water-vapor in order to get rid of fog. In this study, we manufacture anti-fog window device which has better transparence and gets high temperature by using ITO.

• 한국소음진동공학회논문집
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• 제17권6호
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• pp.477-483
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• 2007

Major noise source in high speed rotating optical disk drives (CD and DVD-ROM) arises due to the high-speed airflow produced from the upper and lower surfaces on the rotating disk. The present paper deals with the experimental approach how to identify the noise source based on the fundamental principles of aeroacoustics and to propose a reduction method of the noise source. The CD-ROM device is composed of disk, window tray, motors at the bottom place and electronic circuit plate also located below the window plate. The window is cut in the tray to read the disk information using the optical device located below the tray and moving linearly from the center of the disk through the end of the disk. All components are possible noise generators. Experimental studies were carried out in the anechoic room with various design modifications, such as tray geometry, window size and hole location on tray, to identify the major aerodynamic noise source and significant reductions of the aerodynamic noise were obtained.

• Journal of the Optical Society of Korea
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• 제15권3호
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• pp.272-277
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• 2011

The effect of the M-window color mixing bar on the characteristics of color mixing and hot spots in the edge-lit backlight employing red (R), green (G), blue (G) light emitting diodes (LED) were studied in terms of the structure of the M-window color mixing bar. The rays from RGB LEDs entering the M-window bar were mixed by internal reflection and scattering inside the M-window bar so that the hot spots and color separation were minimized. The M-window bar was designed and fabricated and the simulation results are matched quite well to experimental data.

• Journal of the Optical Society of Korea
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• 제15권3호
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• pp.278-282
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• 2011

We discuss two possible optical noise sources in an electro-optic camera loaded on a low earth orbit satellite. The first noise source was a reflection at the window for signal rays incident upon the window which is placed before the FPA plane. The second noise source came from a reflection at the surface of the FPA cell when the signal flux is not entirely absorbed. We investigate the noise generation processes for two optical noise sources, and a parametric solution is used to estimate the optical noise effects.

• Journal of the Optical Society of Korea
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• 제14권1호
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• pp.28-32
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• 2010

We demonstrate binary spectral phase coded waveform discrimination at 10 GHz for narrow band optical code-division multiple-access (NB-OCDMA) via direct electrical detection without using any optical hard-limiter. Only 9 phase-locked, 10 GHz spaced, spectral lines within a 100 GHz spectral window are used for the phase coding. Considerably high contrast ratio of 5 between signal and multiuser access interference noise can be achieved for $4{\times}10\;G\;pulse/sec$ timing coordinated OCDMA at a simple electrical receiver with 50 GHz bandwidth.

• 한국광학회:학술대회논문집
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• 한국광학회 2004년도 제15회 정기총회 및 동계학술발표회
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• pp.244-245
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• 2004

• 한국광학회:학술대회논문집
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• 한국광학회 1998년도 제15회 광학 및 양자전자 학술발표회 논문집
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• pp.102-103
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• 1998

• 한국광학회:학술대회논문집
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• 한국광학회 2001년도 하계학술발표회
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• pp.54-55
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• 2001