• Title/Summary/Keyword: light wavelength

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식용작물재배 LED 등기구 모듈개발

  • Song, Yong-Jong;Choe, Hyeon-Ho;Lee, Mun-Ho;Kim, Yeong-Pyo;Lee, Ho-Sik;Song, Min-Jong;Kim, Tae-Wan
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2009.11a
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    • pp.284-284
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    • 2009
  • The LED of cultivation edible plants was compliance the variable of the photo-receptor pigment with the red light source and ultra red light source from long wave region. The mechanism of cultivation edible plants for each part was necessary the wavelength unit which is appropriate, the illuminant source, motor control and lens design of LED light source about plant. The photo-receptor pigment induces for a long daytime recognition, seed germination and anthesis etc, induction years exists in the state which is an inactivity within the cells and in compliance with the red light source to be converted in active

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Spectral Resolution Enhancement of Acousto-Optic Tunable Filter(AOTF) using Incident Angle Variation (음향광학변조필터의 입사각 변화를 이용한 분해능 향상 방법)

  • You, Jang-Woo;Ahn, Jeong-Ho;Kim, Dae-suk;Kwak, Yoon-Keun;Kim, Soo-Hyun;Lee, Yun-Woo;Whang, In-Duk
    • Proceedings of the KSME Conference
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    • 2004.11a
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    • pp.607-612
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    • 2004
  • Spectral resolution enhancement method of Acousto-Optic Tunable Filter (AOTF) using incident light angle variation is described. AOTF is a small, mechanically rigid, high speed and spectral resolution light tunable filter. The basic theory of AOTF and its experimental verification is described. AOTF can generate two opposite polarized light simultaneously which wavelength can be changed by incident angle variation. We focused on the common region of two filtered light at the specific incident angle. This region can be used to enhance the spectral resolution of AOTF.

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A Study on Electron Emission Characteristics of Photocathode Formed Under Condition in N2 Atmosphere (상압에서 제조한 포토캐소드의 전자방출 특성에 관한 연구)

  • Jeong, Hyo-Soo
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.27 no.5
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    • pp.312-316
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    • 2014
  • Photoemission is a process in which photons are converted into free electrons. Photocathodes are the typical materials for the process. They emit electrons when a light is irradiated upon. The traditional method of manufacturing photocathodes is complicated, requires specialized equipment, and is limited very small sized samples. $Cs_3Sb$ photocathode was formed on a substrate in $N_2$ atmospheric conditions. The photocathode formation was a gas phase reaction with the substrate. Vacuum devices were made to test electron emission characteristics of the formed photocathode. Visible light of wavelength 475 nm was used for the primary light source. The results showed high current density and long term stability of the photoelectron emission.

The Development of wavelenth of light 7Color dispersion using GPU (GPU를 이용한 빛의 파장에 따른 7색 분산 연구)

  • Gwak, yong-sik;Ryoo, seung-taek
    • Proceedings of the Korea Contents Association Conference
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    • 2009.05a
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    • pp.66-69
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    • 2009
  • Dispersion depending on the wavelength of light that is divided, composed of multiple wavelengths of light.Prism and the rainbow is a visible example of the principle of distributed phenomena. RGB 3 Color Dispersion is can't be expressed in detail. 7 kinds of colors of the Visible light area was distributed, this research to solve the problem of how to distribute these to RGB.The spectral representation for 3 Color Dispersion.

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Enhanced Photodetection with Hot Electrons in Graphene-mediated Plasmonic Nanostructure

  • Kim, Jeong Hyeon;Yeo, Jong-Souk
    • Proceedings of the Korean Vacuum Society Conference
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    • 2014.02a
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    • pp.408-408
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    • 2014
  • Graphene has received attention with its high electron mobility and visual transparency as a promising material for optoelectronic and photonic applications. Combination of graphene and conducting nanostructures i.e. plasmonic structures has recently been researched for enhancing light-matter interaction and overcoming diffraction limit of light. Here we show enhanced photodetection of incoherent visible light with graphene-mediated plasmonics. Gold nanoparticles fabricated by focused ion beam was used as an active element of photodetection and graphene was utilized as an interfacing material between nanostructures and electrodes. Hot electrons generated upon plasmon decay within nanoparticles pass over the potential barrier between nanostructure and graphene and give rise to a photocurrent with built-in electric field. We report 76.7% enhancement of photocurrent under resonant irradiation of fiber-coupled halogen lamp compared to the case without light illumination. We showed wavelength-dependent current response arisen from plasmonic nanostructure, providing a good agreement with theoretical calculation.

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Photoresponsive Behavior of Liquid-Crystalline Networks

  • Yu, Yanlei;Ikeda, Tomiki;Nakano, Makoto
    • 한국정보디스플레이학회:학술대회논문집
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    • 2002.08a
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    • pp.34-37
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    • 2002
  • Freestanding azobenzene-containing liquidcrystalline network (LCN) films. with macroscopic uniaxial molecular alignment were prepared by insitu photopolymerization. By polarizing microscopy, fiber-like structures aligned in one direction were observed. Furthermore, with a confocal laser scanning microscope (CLSM), it was confirmed that the fiber-like structures were formed even in the bulk of the LCNs. Upon UV light irradiation to cause trans-cis photoisomerization of the azobenzene molecules, the LCNfilms underwent a significant and anisotropic bending toward the irradiation direction of UV light. When the bent LCNfilms were exposed to Vis light, unbending of the LCN films immediately took place and the initial flat LCN films were restored. This bending and unbending behavior of the LCN films could be repeated just by changing the wavelength of the irradiation light. It was suggested that the bending was induced by an absorption gradient which produced a volume difference between the front surface area and the bulk of the network films.

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Effect of photosensitizer aganist anti-red tide substances from korea seaweed extracts

  • Jin, Hyung-joo;Jin, Long-Guo;Hong, Sung-Youl;Hong, Yong-Ki
    • Proceedings of the Korean Society of Fisheries Technology Conference
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    • 2000.05a
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    • pp.153-154
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    • 2000
  • Many bioactive photosensitizers have been isolated from plants and some of theses possess antiviral activities which, depend on UVA(320-400nm) and visible light. Many complex quinonoids have been isolated from plants and recently some of them, such as hypericin and hypocrellin, have been shown to possess light-dependent antiviral activities. these compounds only exert their desired biological activities in the presence of long wavelength ultra-violet UVA but these activities are also strongly influenced b chemical structure(Hudson et al, 1995). the importance of light in the use of certain medicinal plant extracts has been appreciated, if not understood, for centuries. Also, many seaweed extracts will effect photo(UVA, visible light) for algicidal activity. (omitted)

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