• 제목/요약/키워드: optical transparency

검색결과 310건 처리시간 0.024초

$TiO_2-SiO_2$ 이성분계 Aerogel의 광학적 투명성과 미세구조 (Optical Transparency and Microstructure of $TiO_2-SiO_2$ Binary Aerogels)

  • 이종혁;최수영;김창은;김구대;이해욱
    • 한국세라믹학회지
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    • 제32권3호
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    • pp.321-330
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    • 1995
  • Homogeneous and monolithic TiO2-SiO2 binary aerogels were prepared by supercritical drying. Optical transparency was increased with adding acid catalyst during two step hydrolysis and with decreasing water content. These differences in optical transparency were related to microstructures of gel network formed through polycondensation reaction during supercritical drying process, rather than the final composition of aerogel.

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Investigation of thermal annealing effects on the optical transparency and luminescent characteristics of Eu-doped Y2O3 thin films

  • Chung, Myun Hwa;Kim, Joo Han
    • Journal of Ceramic Processing Research
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    • 제20권4호
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    • pp.431-435
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    • 2019
  • The thermal annealing effects on the optical transparency and luminescent characteristics of the Eu-doped Y2O3 thin films have been investigated. The as-deposited Y2O3:Eu films exhibited an optical band gap of 5.78 eV with a transparency of 89 % at a wavelength of 550 nm. As the annealing temperature increased from 1000 to 1300 ℃, the optical band gap and transparency of the films decreased from 5.77 to 4.91 eV and from 86.8 to 64.5 % at 550 nm, respectively. The crystalline quality of the films was improved with increasing annealing temperature. The annealed Y2O3:Eu films emitted a red-color photoluminescence (PL) with the highest emission peak near 612 nm. The PL intensity was increased with increasing annealing temperature to 1200 ℃, resulting from the improvement in the crystalline quality of the films. The PL intensity was decreased with further increasing temperature above 1200 ℃ due to the formation of Y2SiO5 phase by the reaction of the film with the quartz substrate.

화학증착법에 의해 제조된 Sb-doped $SnO_2$ 박막의 전기적 및 광학적 특성 (Electrical and Optical Properties of Sb-doped SnO2 Films Prepared by Chemical Vapor Deposition)

  • 이수원;김광호
    • 한국세라믹학회지
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    • 제29권4호
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    • pp.319-327
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    • 1992
  • Sb-doped SnO2 films were formed on Corning glass 7059 substrate by chemical vapor deposition using simulataneous hydrolysis of SnCl4 and SbCl5. Fairly good transparent conducting film with a low resistivity of ~6$\times$10-4{{{{ OMEGA }}cm and high average optical transparency above ~85% in the range of visible light was obtained at the deposition condition of 50$0^{\circ}C$ and input-gas ratio, [Psbcl5/Psncl4] of 0.05. Film conductivity was improved without loosing optical transparency at light doping of Sb and found to be due to the increase of electron concentration. However, high doping of Sb into SnO2 film largely deteriorated conductivity, optical transparency and crystallinity of the film.

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화학증착법에 의한 $SnO_2$ Film의 전기적 및 광학적 성질 (Electrical and Optical Properties of $SnO_2$ Thin Films by Chemical Vapor Deposition)

  • 김광호;김태옥;천성순
    • 한국세라믹학회지
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    • 제23권5호
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    • pp.81-85
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    • 1986
  • $SnO_2$ thin films have been prepared by chemical vapor deposition technique. Electrical and optical properties of the films have been investigated. It is found that the electrical condictivity and optical transparency of the films are most affected by deposition temperature and more affected by $SnCl_4$ partial pressure than by $O_2$ partial pressure. Experimental results show that the conductivity increases with high optical transparency as deposition temperature increases up to 50$0^{\circ}C$ but the conductivity decreases with the loss of transparency as deposition temperature increases above $600^{\circ}C$.

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DOT-3 브레이크액에서 오염에 따른 광학적 특성 연구 (A study of the Optical Characteristics for Contaminated Brake Fluid, DOT-3)

  • 지인근;김여환
    • 한국정보전자통신기술학회논문지
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    • 제8권5호
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    • pp.354-358
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    • 2015
  • DOT-3 규격의 자동차 브레이크액에 대하여 수분 함유량과 시스템 마찰로 인한 오염도를 전기저항과 광학 투과율을 측정하여 비교하였다. 기존의 저항측정법은 수분 함유량을 주로 측정하는 반면에 광학 투과율 방식은 제동장치 내부의 마찰에 의하여 발생된 입자의 오염을 포함하여 측정할 수 있어서 저항변화 측정보다는 광학 투과율 방법이 더 선형적이고 효율적이었다.

스텔스 전투기 캐노피를 위한 투명 전자파 흡수구조 설계 (Design of Transparent Electromagnetic Absorbing Structure for Stealth Aircraft Canopy)

  • 홍익표
    • 한국군사과학기술학회지
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    • 제18권4호
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    • pp.369-375
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    • 2015
  • In this paper, transparent circuit analog radar absorbing structure with angular stability for stealth aircraft canopy was proposed and designed. To obtain wideband electromagnetic absorption, optical transparency and smaller thickness, we proposed the novel FSS(Frequency Selective Surface) for X-band and implemented the resistive FSS and PEC(Perfect Electric Conductor) plane using ITO(Indium Thin Oxide) coating with optical transmissivity of 90 %. Reflection loss characteristics for different incident angles of both TE(Transverse Electric) and TM(Transverse Magnetic) polarizations are presented through simulations. We then fabricated the proposed structure to verify the simulation results. The comparisons between the simulation and measured results show good agreements. The results also show that the proposed radar absorbing structure can provide better frequency stability for different incidence angles and polarizations as well as optical transparency. We can apply this proposed structure to the canopy of stealth aircraft and other stealth applications for visible transparency.

Metal Grid Mesh 인쇄를 이용한 투명 전파 흡수구조 설계 (Design of Transparent Electromagnetic Absorbing Structure using Metal Grid Mesh Printing)

  • 윤선홍;이준상;이인곤;홍익표
    • 한국군사과학기술학회지
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    • 제19권3호
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    • pp.294-301
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    • 2016
  • In this paper, we designed the transparent circuit analog radar absorbing structure using printed metal grid mesh for enhanced optical transmittance. To obtain wideband electromagnetic absorption and enhanced optical transparency at X-band, we proposed the resistive FSS(Frequency Selective Surface) using printed metal mesh pattern on transparent glass with PEC(Perfect Electric Conductor) plane using ITO(Indium Thin Oxide) coating. We then fabricated the proposed structure to verify the simulation results obtained from commercial EM simulator. The comparisons between the simulation and measured results show good agreements. The results also show that the proposed radar absorbing structure can provide wideband reflection as well as better optical transparency. We can apply this proposed structure to the canopy of stealth aircraft and other stealth and security applications for visible transparency.

콜린 로우(Colin Rowe) '투명성(transparency) 이론'의 비판적 고찰 - 투명성에 내재된 시간 개념의 분석을 중심으로 - (A Critical Study on Colin Rowe's 'Transparency' - Focusing on the Analysis of the meaning of 'Time and Simultaneity' implicated in 'Transparency' -)

  • 권태일
    • 건축역사연구
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    • 제15권2호
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    • pp.115-136
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    • 2006
  • Colin Rowe's 'Transparency' is one of core ideas applied to 20th Modern Architecture. It implies not only an optical characteristic, the perfectly clear, but also a broader spacial order, a simultaneous perception of different spacial locations. The former connected with physical attribute itself, and the latter deeply with the metaphorical idea of time, 'Simultaneity', embodying a new spacial quality. However, If we analyze the meaning of "Simultaneity" implicated in "Transparency" with the perspective of Henry Bergson's "Duration", there would be only little possibility as a solution to the problem of embodying a new spacial quality in architecture. As such a question emerging, this paper attempts to point out the problem of Colin Rowe's idea, "Simultaneity", and suggest a new architectural design method to overcome its inconsistency by interpretation and application of Bergson's "Image and Rhythm".

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