• 제목/요약/키워드: Diffraction efficiency

검색결과 575건 처리시간 0.032초

Ag 두께의 변화에 따른 chalcogenide layer의 회절효율 특성

  • 남기현;정홍배
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2009년도 추계학술대회 논문집
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    • pp.197-197
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    • 2009
  • We have investigated the holographic grating formation on Ag-doped amorphous chalcogenide AsGeSeS thin films with Ag thickness. Holographic gratings have been formed using Diode Pumped Solid State laser (DPSS, 532.0nm) under [P:P] polarized the intensity polarization holography. The diffraction efficiency was obtained by +1st order intensity.

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Effect of Nano-sized Silicas in HPDLC Based on PUA

  • Kim, Eun-Hee;Woo, Ju-Yeon;Kim, Byung-Kyu
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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    • pp.1212-1215
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    • 2004
  • Diffraction modes of holographic grating were fabricated with polyurethane acrylates(PUA). Two types of silica (AEROSIL 200 and AEROSIL R812) were added to reduce the shrinkage of polymer matrix. It was founded that shrinkage of PUA composite film was reduced with the addition of silica. HPDLC based PUA/silica composite also showed high diffraction efficiency. The morphology of the resultant gratings was analyzed by using scanning electron microscopy(SEM) and Tg of the polymer matrix by dynamic mechanical thermal analysis(DMTA).

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충격식 코로나 방전 플라즈마를 이용한 배연가스로부터 먼지제거에 대한 특성 (The Characteristics of Dust Removal in Flue Gas by the Plasma of Impulse Streamer Corona)

  • 김은호
    • 한국환경과학회지
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    • 제12권12호
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    • pp.1261-1267
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    • 2003
  • On the basis of the distribution of particle size measured by laser diffraction spectrometers, this research was carried out to investigate the characteristics of mist removal with the change of operating condition in the plasma reactor of impulse streamer corona. The operating parameters in this experiment were power of impulse streamer corona, gas velocity, impulse generation time, gas temperature, and SOx/NOx concentration. The collection efficiency T(d) was estimated by the distribution of particle size in the collection zone through the advanced model.

비정질 As2Se3 박막의 Ag 의존적 홀로그래픽 격자 형성 특성 분석

  • 남기현;김장한;정홍배
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2011년도 제40회 동계학술대회 초록집
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    • pp.275-276
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    • 2011
  • We have investigated the holographic grating formation on Ag-doped amorphous chalcogenide As2Se3 thin films with Ag layer. The basic optical parameter which is a refractive index and extinction coefficent was taken by n&k analyzer. The source of laser was selected based on these parameter. Holographic gratings have been formed using He-Ne laser (wavelength: 632.8 nm) Diode Pumped Solid State laser (DPSS, wavelength: 532.0 nm) under [P:P] polarized the intensity polarization holography. The diffraction efficiency was obtained by +1st order intensity.

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Holographic femtosecond laser processing

  • Hayasaki, Yoshio
    • 한국광학회:학술대회논문집
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    • 한국광학회 2008년도 하계학술발표회 논문집
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    • pp.61-63
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    • 2008
  • Parallel femtosecond laser processing using a computer-generated hologram (CGH) displayed on a liquid crystal spatial light modulator (LCSLM) is demonstrated. The use of the LCSLM enables to perform an arbitrary and variable patterning. This holographic femtosecond laser processing has advantages of high throughput and high light-use efficiency. A critical issue is to precisely control the intensities of the diffraction peaks of the CGH. We demonstrate some methods for the control of the diffraction peaks. We also demonstrate the laser processing with two-dimensional and three-dimensional parallelism.

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RBAO 세라믹스 공정에서 어트리터 효율에 미치는 볼 크기의 영향 (The Effects of Ball Size on Attritor Efficiency in the Processing of RBAO Ceramics)

  • 김일수;강민수;박정현
    • 한국세라믹학회지
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    • 제35권4호
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    • pp.406-412
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    • 1998
  • The reaction bonded alumina ceramics was prepared through the addition of each SiC and ZrO2 powder to the mixture of Al metal powder and Al2O3 The mono sized (3mm) and biodal sized (3mm+5mm) balls were used in attrition milling of Al and starting powders. The milling efficiency of both cases was compared by the analysis of particle size and X-ray diffraction. After the forming and sintering of each powder batchs the weight gains dimensional changes and densities were determined. The specimens were investigated by X-ray diffraction analysis and scanning electron microscope. Bimodal sized balls had better milling effect than single ball size in the milling of Al powder. However in the milling which ceramic powders mono sized the green body during the reaction sintering at 1$600^{\circ}C$ for 5 hour was about 10% The densities attained the values of 92-98% theoretical. The SiC added specimen that was milled with 3mm ball media had 96% theoretical density and dense microstructure.

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Ag/As-Ge-Se-S 다층박막에서 편광상태에 따른 홀로그래피 격장 형성 특성 (Characteristics of the Polarization-Dependent Holographic grating formation on Ag/As-Ge-Se-S Multi-Layer)

  • 나선웅;이정태;여철호;이영종;정홍배
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2002년도 춘계학술대회 논문집 디스플레이 광소자 분야
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    • pp.85-88
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    • 2002
  • We have carried out two-beam interference experiments to form holographic gratings on chalcogenide $Ag/As_{40}Se_{15}S_{35}Ge_{10}$ multi-layer. In this study, holographic gratings have been formed using He-Ne laser(632.8nm) under different polarization combinations(intensity polarization holography, phase polarization holography). The diffraction efficiency was obtained by +1st order intensity and formed grating structure was investigated using atomic force microscopy.

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방음벽 성능 예측을 위한 시간영역 수치해석의 개발 (Development of Time Domain Numerical Computation for Predicting Noise Barrier Efficiency)

  • 임창우;정철웅;이수갑
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2001년도 춘계학술대회논문집
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    • pp.757-761
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    • 2001
  • In order to study noise barriers of complex shapes and to assess their efficiency, precise prediction model is required. For instance, geometrical approaches cannot deal with complex diffraction effects. So that in this paper, the time domain numerical computation method(Computational Aeroacoustics method) is applied to estimate noise reduction by diffraction and finite impedance condition. The CAA method can be used to calculate exactly the pressure of complex barrier shape with different impedance condition, such as T-shape, cylindrical edge and multi-edge noise barriers.

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비정길 칼코게나이드 As-Ge-Se-S 박막에서 편광기록 재생 (Polarization recording and reconstruction in the chalcogenide As-Ge-Se-S thin films)

  • 장선주;박종화;손철호;정홍배
    • 한국전기전자재료학회논문지
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    • 제13권9호
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    • pp.781-785
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    • 2000
  • Chalcogenide glasses are suggested as a candidate for optical recording. In this study, we have investigated the holography recording and reconstruction of the polarization state in chalcogenide As$_{40}$ Ge$_{10}$Se$_{15}$ S$_{35}$ thin films. We have used a He-Ne laser light(633nm) to probe and record of the grating. Also the polarization state of object beam was modulated with a λ/4 wave plate. The polarization state of the +1st order diffracted beam was generated by readout of the grating with a linearly polarized reference beam. It was the same-handed polarization state as the polarization state of the recording beam. The result is shown that the diffraction efficiency of circularly polarized recording represents higher than other polarization state.ate.e.

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The Elimination Characteristics by Impressed Voltage of Holography Grating in Chacogenide Thin Film

  • Lee Ki-Nam;Yeo Cheol-Ho;Yang Sung-Jun;Chung Hong-Bay
    • Transactions on Electrical and Electronic Materials
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    • 제5권6호
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    • pp.219-222
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    • 2004
  • This paper discovers that there are some peculiar properties that can remove holography grating, which was made in chacogenide thin film by impressed voltage. The thin films were used are $As_{40}Ge_{10}Se_{15}S_{35}$, and we use He-Ne laser in order to form thin films. I-V curved line in a thin film before a lattice was made has the critical point, about 3.7 V. Moreover, the I-V curved line increased current intensity at over 4 V after it made thin film. In addition, while holography grating is being made, and when it has the highest diffraction efficiency, a lattice can be deleted if put more voltage into it.