• 제목/요약/키워드: Diffraction efficiency

검색결과 573건 처리시간 0.026초

DPSS laser를 이용한 비정질 칼코게나이드 박막의 회절격자 형성

  • 남기현;정원국;정홍배
    • 한국진공학회:학술대회논문집
    • /
    • 한국진공학회 2009년도 제38회 동계학술대회 초록집
    • /
    • pp.246-246
    • /
    • 2010
  • In this paper, we investigated the diffraction grating efficiency on AsSeS and Ag-doped amorphous chalcogenide Ag/AsSeS thin film for used to volume hologram. The Chalcogenide film thickness was 0.5um and Ag thin film was varied from 10nm and 20nm. Diffraction efficiency was obtained from (P:P) polarized Diode Pumped Solid State laser(DPSS, 532.0nm: 200mW) beam on AsSeS and Ag/AsSeS thin films. As a results, diffraction grating was not formed at AsSeS thin film but at Ag-doped AsSeS thin film, diffraction grating was formed well compare with the former.

  • PDF

TiO2 나노 입자를 첨가한 광고분자 필름의 회절효율 값에 대한 연구 (Study of Diffraction Efficiency Values for Photopolymer Films Added TiO2 Nanoparticles)

  • 허기영;김대흠
    • 한국광학회지
    • /
    • 제20권2호
    • /
    • pp.123-127
    • /
    • 2009
  • 본 연구에서는 광고분자의 광특성을 향상시키기 위하여, $TiO_2$를 첨가시킨 광고분자를 제조하고, 그 광학 특성을 연구하였다. 광고 분자는 PVA를 바인더로, AA를 모노머로, TEOA를 개시제로, Eosin Y를 광감각제로 사용하여 제조하였다. 균일한 두께의 광고분자 필름을 얻기 위하여, 스핀 쿼터를 이용하여 일정양의 광고분자 용액을 슬라이드 글라스에 펼쳐 제조하였다. 건조 조건은 $25^{\circ}C$, 습도 60%, 72시간을 유지하였고, 이렇게 제작된 광고분자 필름을 $20{\sim}70$도 범위의 다양한 입사각에서 회절효율을 측정하였다. 그 결과, $TiO_2$가 첨가된 광고분자 필름은 무첨가 필름보다 5% 정도 높은 회절효율 값을 나타내었다. 뿐만 아니라, $TiO_2$의 첨가는 넓은 입사각 범위에서도 높은 효율을 나타내는데 효과적이었다.

Photopolymer Composed of a Photosensitive Polymer Binder Bearing a Chalcone Moiety in the Repeating Unit

  • Cho, Min-Ju;Yoon, Hyuk;Feng, Dejun;Yoon, Han-na;Choi, Dong-Hoon
    • Journal of Information Display
    • /
    • 제7권2호
    • /
    • pp.6-11
    • /
    • 2006
  • New photopolymers were designed and prepared using the photosensitive polymer binders. Holographic gratings were successfully fabricated in these photopolymer samples by a conventional optical interference method. We also investigated the effect of photocrosslink in the polymer binder on the diffraction behavior of a new photopolymer. The dynamic behavior of the grating formation was monitored by changing exposure intensity in terms of the diffraction efficiency. Particularly, we focused our efforts in observing the variation of diffraction efficiency during a post UV curing process. The surface topographical change of photopolymer layer before and after Vis/UV light exposure was observed by atomic force microscope (AFM). We inscribed the gratings of the glass diffuser on the surface of the photopolymer and investigated their diffusing properties. The diffusers with photopolymer with the main chain polymer binder showed relatively good viewing angle of around ${\pm}30{\circ}$. Two kinds of photopolymer showed similar uniformity of around 47-54%.

Diffraction Behaviors of New Photopolymers and their Diffuser Properties

  • Yoon, Hyuk;Kim, Jae-Hong;Lee, Seung-Hwan;Paek, Sang-Hyon;Choi, Dong-Hoon
    • Journal of Information Display
    • /
    • 제5권1호
    • /
    • pp.22-27
    • /
    • 2004
  • Photopolymers are quite promising candidates for holographic data storage and diffusers because of their high sensitivity and high refractive index modulation. New photopolymers were prepared using the cellulose ester binder bearing different kinds of monomer. The holographic gratings were elaborated successfully in these photopolymer samples by conventional optical interference method. We investigated the dynamic behavior of the diffraction efficiency and the effect of the functionality of the monomer doped into the polymer binder. Triacrylate monomer doped photopolymer showed the highest diffraction efficiency of around 80-90 %, even under low intensity of writing beam (I=2 mW/$cm^2$). We inscribed the gratings of the glass diffuser on the surface of the photopolymer and investigated their diffusion properties.

SBC 시스템 구성을 위한 단순한 구조를 가지는 고효율 무편광 유전체 다층박막 회절격자 설계 (Design of a Simply Structured High-efficiency Polarization-independent Multilayer Dielectric Grating for Spectral Beam Combining)

  • 조현주;김관하;김동환;이용수;김상인;조준용;김현태;곽영섭
    • 한국광학회지
    • /
    • 제31권4호
    • /
    • pp.169-175
    • /
    • 2020
  • 격자의 구조가 간단하고 격자의 대조비가 낮은 SBC 시스템 구성을 위한 무편광 유전체 다층박막 회절격자를 설계하였다. SBC 방법으로 결합한 빔의 빔 품질을 높게 유지하기 위하여 회절격자의 파면 왜곡이 최소화되는 구조를 제안하였으며, 오염에 의한 흡수가 발생하지 않고 회절격자를 제작할 수 있는 구조로 회절격자를 최적화 설계하였다. 설계된 회절격자는 1055 nm 중심파장에서 Littrow 각도로 입사하는 경우 무편광 -1차 회절 효율이 99.36%이었으며, 96% 이상의 무편광 회절 효율을 나타내는 공정 여분이 확보되어 있음을 확인하였다.

기록빔의 편광상태에 따른 $AS_{40}Se_{15}S_{35}Ge_{10}$ 박막에서 홀로그래피 회절격자형성 특성 (Characteristics of Holographic Diffraction Grating Formation on $AS_{40}Se_{15}S_{35}Ge_{10}$ Thin Film with the Polarization State of Recording Beam)

  • 박정일;정홍배
    • 대한전기학회논문지:전기물성ㆍ응용부문C
    • /
    • 제55권9호
    • /
    • pp.423-428
    • /
    • 2006
  • We have been carried out the two-beam interference method to form the diffraction grating on chalcogenide $AS_{40}Se_{15}S_{35}Ge_{10}$ thin films for Holography Data Storage (HDS). In the present work, we have been formed holographic diffraction gratings using He-Ne laser (632.8nm) under different Polarization state combinations (intensity polarization holography, phase polarization holography). It was obtained the diffraction grating efficiency by 11st order intensity and investigated the formed grating structure using Atomic Force Microscopy (AFM). As the results, it is shown that the diffraction efficiency of (P: P) polarized recording was maximum 2.4% and we found that its value was rather higher than that of other-polarized recordings. From the results, it is confirmed that the efficient holographic grating formation on amorphous chalcogenide $AS_{40}Se_{15}S_{35}Ge_{10}$ films depend on both the spatial variation of intensity and the polarization state of the incident field pattern.

홀로그래픽 광학소자 제작을 위한 dichromated gelatin 연구 (A Study on Dichromated Gelatin for Recording of HOE)

  • Man Ho Jeong
    • 한국광학회:학술대회논문집
    • /
    • 한국광학회 1990년도 제5회 파동 및 레이저 학술발표회 5th Conference on Waves and lasers 논문집 - 한국광학회
    • /
    • pp.112-114
    • /
    • 1990
  • A method for fabrication of holographic optical elements (HOE) using dichromated gelatin (DGG) as a recording material is presented. we describe the holographic properties of the DGG and the processing techniques. Holographic characteristics of the DGG including exposure characteristics, diffraction efficiency and angular sensitivity are also discussed. The diffraction efficiency of the obtained holographic grating is about 84%.

  • PDF

저온플라즈마에 의한 배연 가스내의 미스트 처리기술 (The Technology of Mist Removal in Flue Gas by the Plasma of Impulse Streamer Corona)

  • 하상안;김일배;강신묵
    • 환경위생공학
    • /
    • 제14권4호
    • /
    • pp.69-76
    • /
    • 1999
  • This research was carried but to investigate the characteristics of mist removal with the change of operating conditions in the plasma reactor of impulse streamer corona based on the distribution of particle size measured by laser diffraction spectrometers. The operating conditions in this experiment were power of impulse streamer corona, gas velocity, collection time, and SOx/NOx concentration. The collection efficiency T(d) was estimated by distribution of particle size in the collection zone through the advanced model.

  • PDF

Design and Analysis of Color Separation Grating by Using Fresnel Diffraction Theory

  • Chen, Chien-Hung;Lin, Hoang-Yan
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
    • /
    • pp.1505-1509
    • /
    • 2006
  • We use the color separation grating (CSG) to split colored light into the sub-pixel of LCD to enhance the optical efficiency as compared with that of using color filter. Based on the Fresenl diffraction theory, the theoretical optical efficiency can reach 66-81%, ranging almost from 2 to 2.5 times of that using color filters.

  • PDF

반도체가 첨가된 유리의 암색화에 따른 포화흡수 변화와 영구 회절격자의 회절효율 연구 (The Absorption Saturation and Diffraction Efficiency of the Permanent Gratings Due to the Photodarkening in Semiconductor Doped Glasses)

  • 백성현;신상훈;김상천;최문구;박승한;김웅
    • 한국광학회지
    • /
    • 제6권4호
    • /
    • pp.331-336
    • /
    • 1995
  • 미세 반도체가 첨가된 유리에 암색화에 따른 정상상태 포화흡수 변화를 조사하였고 축퇴 4광파 혼합 실험으로 영구 회절격자를 형성시켜 회절 효율을 연구하였다. 사용된 레이저는 Q-switch된 Nd:YAG레이저의 제2조화파로 펼스폭은 15ns이었다. 시료가 암색화된에 따라 포화 흡수세기 $I_s$는 증가하였고, 축퇴 4광파 혼합 실험 장치로부터 전방 펌프빔과 조사빔에 의한 큰 간격의 영구 회절격자를 형성하여 후방 펌프빔의 세기에 따라 회절 되어 나오는 빛의 세기를 측정하였다. 영구 회절격자는 암색화 현상에 의한 것으로 회절효율은 회절 되는 후방 펌프빔의 세기가 크지 않을 때 그 세기에 비례하는데, 이는 암색화에 의해 형성된 회절격자 사이의 흡수 차이에 의한 것임을 알 수 있었다.

  • PDF