• Title/Summary/Keyword: Optical spectrum

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THE RED COLOR OF MARS FROM OPTICAL SPECTRA

  • LEE, SEUNG-A;LEE, DONG-EUN;JO, YEUNG-HUN;SONG, IN-OK
    • Publications of The Korean Astronomical Society
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    • v.30 no.2
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    • pp.761-763
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    • 2015
  • Colors have been derived from the observed optical spectrum of Mars and Jupiter. It is known that the planets and the Moon emit reflected sunlight and thus their spectra are similar to the spectrum of solar radiation. The question was then why is the color of Mars different from that of other planets, i.e. red, although it would share the same spectrum of reflected sunlight. Can one derive color from the spectrum? Therefore, we observed the optical spectra of the scattered sunlight in day time for the Moon and Mars using a 1-D array spectrograph on the 12-inch reflecting telescope in the Korea Science Academy of KAIST in Busan, Korea. We adopted the International Commission on Illumination (CIE) in 1931 of three spectral sensitivity peaks for the human eye in short, medium and long wavelengths in visible light. The observed spectra were imposed on CIE sensitivities and the color detected by the human eye was derived. The Mars spectrum represents red color and the Moon white. It is a similar color to that which a human would see. This result means that color is easily derived from astronomical spectra. The appearance of the planets surface can be determined for Mars, which is the result of iron oxide.

Dielectric Function Analysis of Cubic CdSe Using Parametric Semiconductor Model (변수화 반도체 모델을 이용한 Cubic Zinc-blonde CdSe의 유전함수 분석)

  • Jung, Y.W.;Ghong, T.H.;Lee, S.Y.;Kim, Y.D.
    • Journal of the Korean Vacuum Society
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    • v.16 no.1
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    • pp.40-45
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    • 2007
  • ZnCdSe alloy semiconductor was widely used for the optoelectronic device. And CdSe is the end-point in this material. In this work, we measured the dielectric function spectrum of cubic CdSe with Vacuum Ultra Violet spectroscopic ellipsometry and analysed this data with parametric model. As a result, we observed some of transition energy point over 6 eV and obtained the database for dielectric function spectrum, which could be used for temperature or alloy composition dependence study on optical property of CdSe.

Layout of Long-pass-edge Filter Correspond with the Optical Transmission in Crystalline (수정체 광투과에 대응하는 LPE Filter 설계)

  • Kim, YongGeun
    • Journal of Korean Ophthalmic Optics Society
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    • v.4 no.2
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    • pp.57-63
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    • 1999
  • The optical absorption and transmittance of cow' crystalline were measured by spectrophotometer in the 200~800nm wavelength regions. The optical absorptions of crystalline composed of a high absorption band in the UV-A, UV-B, and appeared the light transmittance edge in the 400nm wavelength region, and completely transmitted without the absorption in the high wavelength regions than 400nm. Also, the optical absorption and transmittance had no temperature dependence. The optical transmittance spectrum of crystalline concord with the thin film structure of $n_0/(0.5H)L(LH)^6(0.5H)/n_s$ and $n_0{\mid}(0.5LH0.5L)^kL/1.25{\mid}4.0$ of long-pass edge filter form. In the artificial crystalline and inter lens layout, long-pass edge filter layout can UV cut off.

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Research on Far-Infrared Optical Spectra of Blood Substances using FTIR-spectrometer (FTIR Spectrometer를 이용한 혈중성분의 원적외선 분광 스펙트럼에 관한 연구)

  • 김건식;최우석;박승한;전계진;윤길원
    • Proceedings of the Optical Society of Korea Conference
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    • 2000.08a
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    • pp.122-123
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    • 2000
  • 혈중 성분, 또는 생체 시료와 빛의 상호작용에 관한 연구는 비침습적 정량분석, 또는 생체 조직의 상태 분석의 가능성을 의미하므로 많은 분야에서 연구가 진행되고 있다. 최근에는 원적외선 검출소자가 급속히 개발됨에 따라 원적외선(8~15$mu extrm{m}$)영역에서의 생체 시료 및 성분들의 정량적인 분석과 영상에 관한 연구가 큰 주목을 받고 있다. 그중 혈중 Glucose 성분의 정량분석에 관한 연구는 여러가지 분광법-특히 NIR 영역에서 흡수, 투과, ATR, NMR 등-으로 활발히 연구되고 있으며$^{1)}$ , 최근에는 FIR 영역에서 혈중 성분들이 특정한 흡수 봉우리를 가지고 있음이 확인되어 이 영역에서의 분광법과 정량 분석에 대한 관심이 고조되고 있다. 본 연구에서는 혈중 성분들의 원적외선 영역에서 빛과의 상호작용인 흡수 spectrum을 측정하여 정량분석에 대한 가능성을 확인하였다. 생체를 이루는 가장 기본인 물에 대한 흡수 spectrum의 연구를 먼저 수행하였고, 혈중 성분중 Glucose, Hb, Albumin 등의 수용액을 농도별로 흡수 spectrum측정을 하였다. (중략)

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Angular Spectrum of the Spontaneous Emission from Dye Molecules Near a Boundary

  • Choi, Hyun-Ho;Kim, Hyoung-Joo;Noh, Jae-Woo;Park, Dae-Yoon;Jhe, Won-Ho
    • Journal of the Optical Society of Korea
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    • v.6 no.1
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    • pp.1-4
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    • 2002
  • We studied experimentally the angular spectrum of the light emitted from dye Molecules near a plane boundary. It is confirmed that the molecules near the boundary can emit light into the evanescent wave mode, and the light emission with the angle greater than the critical angle is detected with good accuracy. The angular spectrum of the spontaneous radiation is measured, and the spectrum shows contributions from the molecules both near and far away from the boundary. The polarization dependence and the pumping angle dependence are also measured. The experimental results are in good agreement with quantum theory.

The Effect of Front Facet Reflections on the Reflectivity Spectrum of Bragg Reflector structures (단면 반사율이 Bragg Reflector 구조의 전체 반사율 스펙트럼에 미치는 효과)

  • 김부근
    • Proceedings of the Optical Society of Korea Conference
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    • 1991.06a
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    • pp.203-208
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    • 1991
  • We present an analytic equation for the reflectivity spectrum of a Bragg reflector in terms of the front mirror reflectivity, due to the refractive index difference between the refractive index of outside medium and the average refractive index of Bragg reflector structures, and the reflectivity of a Bragg reflector calculated by the coupled wave method. We show that even Fresnel reflection causes the reflectivity spectrum of a bragg reflector to be very different from that of Bragg reflectors calculated by the coupled wave method. The reflectivity spectrum of a Bragg reflector is dramatically changed because the interference effect between the reflected wave from the front facet and that from the Bragg reflector is changed due to the difference of a phase change from a Bragg reflector when the sequence of layers in a Bragg reflector is changed.

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Identification and Determination of Oil Pollutants Based on 3-D Fluorescence Spectrum Combined with Self-weighted Alternating Trilinear Decomposition Algorithm

  • Cheng, Pengfei;Wang, Yutian;Chen, Zhikun;Yang, Zhe
    • Journal of the Optical Society of Korea
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    • v.20 no.1
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    • pp.204-211
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    • 2016
  • Oil pollution seriously endangers the biological environment and human health. Due to the diversity of oils and the complexity of oil composition, it is of great significance to identify the oil contaminants. The 3-D fluorescence spectrum combined with a second order correction algorithm was adopted to measure an oil mixture with overlapped fluorescence spectra. The self-weighted alternating trilinear decomposition (SWATLD) is a kind of second order correction, which has developed rapidly in recent years. Micellar solutions of #0 diesel, #93 gasoline and ordinary kerosene in different concentrations were made up. The 3-D fluorescence spectra of the mixed oil solutions were measured by a FLS920 fluorescence spectrometer. The SWATLD algorithm was applied to decompose the spectrum data. The predict concentration and recovery rate obtained by the experiment show that the SWATLD algorithm has advantages of insensitivity to component number and high resolution for mixed oils.