• 제목/요약/키워드: Polarization Response

검색결과 140건 처리시간 0.028초

INTERPRETATION OF POLARIZATION RESPONSES OF URBAN AREA

  • Kang Moon-Kyung;Yoon Wang-Jung;Kim Kwang-Eun;Choi Hyun-Seok
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
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    • pp.534-537
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    • 2005
  • Polarization of the radar wave refers to the ellipticity angle and orientation angle of the polarization ellipse. An evaluation of the polarization response can help understand the scattering mechanisms involved for a particular area of interest or provide information for image classification and algorithm section. C- and L-band polarization responses measured at urban area show the results that the polarization behavior for dihedral comer reflector or short, thin cylinder reflector appears at located in city streets or buildings site which are lined up and the polarization behavior for a large conducting sphere appears at parts of test site particularly river, flat, and vegetated areas. Also, the co- and cross-polarized response graphs and polarimetric parameters are discussed.

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A Fast Response Smectic LCD using Induced Polarization

  • Mochizuki, Akihiro
    • Journal of Information Display
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    • 제6권3호
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    • pp.6-11
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    • 2005
  • In this paper, a general performance of the PSS-LCD or Polarization Shielded Smectic Liquid Crystal Display is discussed. This smectic base LCD does not use any spontaneous polarization, but uses induced polarization just sa me with current nematic base LCDs. Specific initial molecular alignment as well as specific cell design realizes ext remely fast optical response speed with native wide viewing angle. Moreover, this performance is provided by full compatible electronics for current conventional LCDs. A general performance of the PSS-LCD is introduced herein.

응답 속도 200ms 이하의 편광모드분산 보상기 개발 (Development of Polarization Mode Dispersion Compensator with a response time less than 200ms)

  • 서재은;김상인;정기태
    • 한국정보통신설비학회:학술대회논문집
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    • 한국정보통신설비학회 2003년도 하계학술대회
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    • pp.47-48
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    • 2003
  • A polarization mode dispersion(PMD) compensator with a reponse time less than 200ms has been developed. In our PMD compensator, a reset-free $LiNbO_3$ polarization controller was used in order to reduce the response time, and the compensation algorithm was based on maximization of degree of polarizaiton(DOP).

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InP-Based Polarization-Insensitive Planar Waveguide Concave Grating Demultiplexer with Flattened Spectral Response

  • Kwon, Oh-Kee;Lee, Chul-Wook;Lee, Dong-Hun;Sim, Eun-Deok;Kim, Jong-Hoi;Baek, Yong-Soon
    • ETRI Journal
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    • 제31권2호
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    • pp.228-230
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    • 2009
  • InP-based planar waveguide 48-channel concave grating demultiplexers with a channel spacing of 0.8 nm (100 GHz) are described and demonstrated. Polarization insensitivity and flattened spectral response are successfully achieved by the introduction of a polarization compensator and a two-focus grating, respectively. The fabricated device shows a polarization-dependent wavelength shift of less than 20 pm and a -3 dB spectral width of about 0.55 nm (68.75 GHz) over all channels.

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The Electrorheological and Dielectric Behaviors of Conducting Polymer-coated Poly(ethyl methacrylate) Suspensions

  • Kim, Young-Dae;Park, Dong-Hyup;Nam, Suk-Woo;Park, Tae-Jin
    • Macromolecular Research
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    • 제10권4호
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    • pp.215-220
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    • 2002
  • The electrorheological (ER) and dielectric behaviors of the polypyrrole(PPy)-coated poly(ethyl methacrylate)(PEMA) suspensions in mineral oil were investigated. PPy was coated on PEMA particles to enhance the particle polarization, which would lead to the enhanced ER response. Various PPy-coated PEMA particles were synthesized by controlling the oxidant amount during the pyrrole polymerization, and the ER responses of their suspensions were investigated. The ER response initially increases with the oxidant amount, passes through a maximum, and then decreases with the oxidant amount. The initial increase in the ER response with oxidant amounts is due to the enhanced particle polarization with the increased particle surface conductivity. The dielectric properties of the corresponding suspensions support that the ER enhancement arises from the enhanced particle polarization. The decrease in the ER response at large oxidant amounts seems to arise from the increased conduction between the PPy-coated PEMA particles.

Theory of polarization grating formation induced by the photosensitivity in birefringent optical fibers

  • An, Sunghyuck
    • 한국광학회지
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    • 제5권4호
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    • pp.487-492
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    • 1994
  • The two-photon bleaching model is generalized to derive the dynamical equations which describe the polarization grating formation induced by the photosensitivity in birefringent optical fibers. The frequency response of the induced polarization grating is studied numerically and its relation to the material parameter is investigated.

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PFM을 이용한 AlN 박막의 압전특성 분석에 관한 연구 (A study for piezoelectric properties analysis of the AlN thin film by using PFM)

  • 이종택;김세영;신현창;송준태
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2009년도 하계학술대회 논문집
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    • pp.224-225
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    • 2009
  • Aluminium nitride thin film was deposited on Au electrode and Si substrate by radio frequency sputtering system. X-ray diffraction (XRD) was utilized to identify the AlN phase, and Atomic Force Microscope (AFM) was used to obtain the images of surface morphology and roughness value of AlN thin film. The result of XRD and AFM measurement showed that the AlN thin film has strong c-axs orientation and smooth surface. In order to investigate piezoelectric response and polarization properties along to the direction of electric field, PFM (Piezoresponse Force Microscope) system was used, and the images of piezoelectric response due to switching of polarization was observed by PFM.

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Polarization Insensitive CWDM Optical Demultiplexer Based on Polarization Splitter-rotator and Delayed Interferometric Optical Filter

  • Seok-Hwan Jeong;Heuk Park;Joon Ki Lee
    • Current Optics and Photonics
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    • 제7권2호
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    • pp.166-175
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    • 2023
  • We theoretically analyze and experimentally demonstrate a polarization-diversified four-channel optical demultiplexer (DeMUX) comprising a hybrid mode conversion-type polarization splitter rotator (PSR) and delayed Mach-Zehnder interferometer optical DeMUX for use in coarse wavelength division multiplexing (CWDM)-based optical interconnect applications. The Si wire-based device fabricated by a complementary metal-oxide semiconductor-compatible process exhibited nearly the same filter spectral response irrespective of the input polarization state under the PSR. The device had an extremely low insertion loss of <1.0 dB, polarization-dependent loss of <1.0 dB, and interchannel imbalance of <0.5 dB, suppressing unwanted wavelength and polarization crosstalk from neighboring channels of <-20 dB at each peak transmission channel grid.

격자 사각 루프 형태를 갖는 주파수 선택 반사기 (Frequency selective surface with gridded square-loop elements)

  • 고지환;음만석
    • 전자공학회논문지D
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    • 제34D권9호
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    • pp.7-14
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    • 1997
  • A rigorous analysis method of electromagentic scattering from frequency selective surface with gridded square loop elements in case of oblique incident and arbitrary polarization is presented, which uses the roof-top subdomain basis function. The frequency response and polarization characteristics of the reflected wave and the transmitted wave for various widths of the grid and the conductor square loop, and for the various gaps between the grid and the conductor square loop, and for the various gaps between the grid and square loop is investigated. To confirm the validity of presented method, frequency selective surfaces with gridded square loop elements are fabricated with honeycomb structures, calculate dvalues for the frequency response of the reflected wave and the transmitted wave for arbitrary incident angle and polarization are compared with measured values.

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배향막의 극성에 따른 a-TN-LCD의 전기광학특성에 관한 연구 (A Study on Electro-optical Characteristics of a-TN-LCD with Polarization of Orientation Film)

  • 서대식;이창훈
    • E2M - 전기 전자와 첨단 소재
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    • 제10권10호
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    • pp.1011-1015
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    • 1997
  • In this paper we investigated the electro-optical characteristics of amorphous (a)- twisted nematic (TN)-liquid crystal display(LCD) on polymide (PI) surfaces with different molecular structure. It was found that the domaine size of a-TN-LCD on PI with high polarization is small compared to a-TN-LCD on PI with medium polarization. It is considered that the response time of a-TN-LCd contributes to surface effect between the substrate surfaces and the LC molecules. Finally we obtained that the viewing angle of a-TN-LCD on PI surfaces increases with decreasing the domain size.

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