• 제목/요약/키워드: Electro-optical properties

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Laser Beam Scattering Analysis in Aqueous Environments (액상유체 환경하에서 레이저빔의 산란 해석)

  • Choi, Hae Woon
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.18 no.2
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    • pp.91-95
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    • 2019
  • A new experimental approach is proposed to detect a specific polymer dissolved in a liquid. Distinctive optical properties were found using a laser scattering technique when there is a polymer compound with almost no difference in optical properties (index of refraction) in a liquid phase. The index of refraction, which determines the refraction of light, is obtained by dissolving PCL and PLA. The used samples are biodegradable materials with similar properties and dissolved in a mixture of Chloroform 7: Methanol 3. To predict the optical properties, a 632-nm diode laser was used as the light source of the device, and an integrating sphere was used as the light receiver. Although PCL and PLA had a similar index of refraction of 1.46-1.48, the dissolved PCL showed a relative transmittance of 43%, and the dissolved PLA had a relative transmittance of 34%. The difference in optical properties of the pure polymer compound in the solid state or liquid state is not significantly different, and the difference in the dissolved state in the specific solvent is remarkable because the solubility differs in a specific solution and is randomly distributed.

Influence of Surface Texturing on the Electrical and Optical Properties of Aluminum Doped Zinc Oxide Thin Films

  • Lee, Jaeh-Yeong;Shim, Joong-Pyo;Jung, Hak-Kee
    • Journal of information and communication convergence engineering
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    • v.9 no.4
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    • pp.461-465
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    • 2011
  • An aluminum doped zinc oxide (AZO) film for front contacts of thin film solar cells, in this work, were deposited by r.f. magnetron sputtering, and then etched in diluted hydrochloric acid solution for different times. Effects of surface texturing on the electro-optical properties of AZO films were investigated. Also, to clarify the light trapping of textured AZO film, amorphous silicon thin film solar cells were fabricated on the textured AZO/glass substrate and the performance of solar cells were studied. After texturing, the spectral haze at the visible range of 400 ~750 nm increased substantially with the etching time, without a change in the resistivity. The conversion efficiency of amorphous Si solar cells with textured AZO film as a front electrode was improved by the increase of short-circuit current density ($J_{sc}$), compared to cell with flat AZO films.

Growth and Properties of Co-doped Ce,Mn:LiTaO3 Single Crystals

  • Gang, Bong-Hoon;Rhee, Bum-Ku;Lim, Ki-Soo;Bae, Sung-Ho;Joo, Gi-Tae
    • Journal of the Korean Ceramic Society
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    • v.39 no.8
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    • pp.711-714
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    • 2002
  • The Ce, Mn: $LiTaO_3$ crystals were grown by Czochralski method in congruent ${\varphi}$3" $LiTaO_3$ single crystal growing conditions. Concentrations of Ce and Mn in melt were respectively 0.1 mole%. As-grown crystals were red, transparent and the grown crystals were tested with oxidation/reduction treatment for clor and other properties. Influence of Ce and Mn dopants on $LiTaO_3$ crystal properties was discussed. And the nonlinear optical properties of the Ce, Mn: $LiTaO_3$ crystal are being studied.

Structure and Thermal Properties of SnO2-(1-x)P2O5-xB2O3 Glasses (SnO2-(1-x)P2O5-xB2O3 유리의 열적, 구조적 특성)

  • An, Yong-Tae;Choi, Byung-Hyun;Ji, Mi-Jung;Chang, Woo-Suk;Bae, Hyun;Hwang, Hae-Jin
    • Journal of the Korean Ceramic Society
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    • v.47 no.2
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    • pp.117-121
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    • 2010
  • $SnO_2-(1-x)P_2O_5-xB_2O_3$ glass system were prepared by melt-quenching technique in the compositional series containing 50, 55 and 60 mol% of $SnO_2$. Local structure of the glasses was investigated by Raman and FT-IR measurements. A large glass-forming region was found at the phosphate side of the ternary system with homogeneous glasses containing up to 5~25 mol% of $B_2O_3$. According as content of $B_2O_3$ increases, theraml expansion coefficient of glass decreased but transition temperature and softening temperature increased. Because these phenomenon changed local structure of glass. According as content of $B_2O_3$ increases, quantity of bridging oxygen increased. Also, according as content of $SnO_2$ increases, confirmed that quantity of non-bridging oxygen increases.

Effect of Melting Atmospheres on the Structure and Properties of P2O5-SnO2 Glass Systems (P2O5-SnO2계 유리에서 용융분위기에 따른 구조와 물성에 미치는 영향)

  • An, Yong-Tae;Choi, Byung-Hyun;Ji, Mi-Jung;Kwon, Yong-Jin;Bae, Hyun;Hwang, Hae-Jin
    • Journal of the Korean Ceramic Society
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    • v.49 no.2
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    • pp.191-196
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    • 2012
  • In this study, tin phosphate glass system($SnO_2-(1-x)P_2O_5-xB_2O_3$) that occur during the melting of the metal oxide inhibition of the oxidation reaction, and to reduce oxides of high melting temperature in the following three methods were melting. The first is the general way in the atmosphere, and the second by injecting $N_2$ gas under a neutral atmosphere, and finally in the air were melted by the addition of a reducing agent Melt in the atmosphere when the oxidation of the metal oxide is inhibited by low temperatures were melting. In addition, the deposition of crystals within glassy or inhibit devitrification phenomenon is also improved over 80% transmittance. This phenomenon, when the melting of glass, many of $Sn^{4+}$ ions are reduced to the $Sn^{2+}$ was forming oxides SnO, because it acts as a modifier oxide.

Haze Removal of Electro-Optical Sensor using Super Pixel (슈퍼픽셀을 활용한 전자광학센서의 안개 제거 기법 연구)

  • Noh, Sang-Woo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.6
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    • pp.634-638
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    • 2018
  • Haze is a factor that degrades the performance of various image processing algorithms, such as those for detection, tracking, and recognition using an electro-optical sensor. For robust operation of an electro-optical sensor-based unmanned system used outdoors, an algorithm capable of effectively removing haze is needed. As a haze removal method using a single electro-optical sensor, the dark channel prior using statistical properties of the electro-optical sensor is most widely known. Previous methods used a square filter in the process of obtaining a transmission using the dark channel prior. When a square filter is used, the effect of removing haze becomes smaller as the size of the filter becomes larger. When the size of the filter becomes excessively small, over-saturation occurs, and color information in the image is lost. Since the size of the filter greatly affects the performance of the algorithm, a relatively large filter is generally used, or a small filter is used so that no over-saturation occurs, depending on the image. In this paper, we propose an improved haze removal method using color image segmentation. The parameters of the color image segmentation are automatically set according to the information complexity of the image, and the over-saturation phenomenon does not occur by estimating the amount of transmission based on the parameters.

Phase Separated Structure and Electro-optical Properties of the (Polymer/Liquid Crystal) Composite Films ((고분자/액정) 복합막의 상분리구조와 전기광학 특성)

  • Park, K.S.;Noh, C.H.;SaKong, D.S.;Nam, K.D.;Kajiyama, T.
    • Journal of the Korean Applied Science and Technology
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    • v.12 no.2
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    • pp.29-39
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    • 1995
  • The phase separated structure and the electro-optical properties of the (polymer/liquid) crystal : LC) composite film strongly depended on the weight fraction of LC in it. The continuous LC phase was formed in a three-dimensional polymer network when the LC weight fraction was above 40wt%. The aggregation structure of the composite film could be controlled by controlling the solvent evaporation velocity during the film preparation process. The smaller LC domains or channels were formed in the case of the faster solvent evaporation velocity. The composite film exhibited reversible light scattering-light transmission switching upon electric field -OFF and -ON states, respectiverly. The light scattering properties of the composite film strongly depended on the spatial distortion of the nematic directors as well as the mismatch in refractive indices between matrix polymer and LC.

Non-linear Optical Properties of the Langmuir-Blodgett Films Measured by the Differential Attenuated Total Reflection Method (미분 변조 전반사 감쇠법에 의해 측정된 Langmuir-Blodgett 박막의 비선형 광학적 성질)

  • 정미윤
    • Proceedings of the Optical Society of Korea Conference
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    • 1991.06a
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    • pp.94-97
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    • 1991
  • We have deposited the three kinds of the Langmuir-Blodgett films (Phenylhy drazone, O-stilbazene, N-stilbazene) which have optically nonlinear effect. To study the electro-optic characteristics of these LB films, we performed the differential attenuated total reflection experiment in which the optical properties of the LB films modulated by the electric field(νE = 1KHz). The surface non-linear susceptibilities $\chi$(2) of these LB films obtained, are 1.17$\times$10-10 (m/V), 36.3$\times$10-10 (m/V), and 1.62$\times$10-10 (m/V) for Phenylhydrazone, O-stilbazene, and N-stilbazene, respectively.

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Electrooptic Laser Modulator (전기광학적 레이저 변조기)

  • 이문기
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.12 no.3
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    • pp.13-19
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    • 1975
  • A detailed analysis has been carried out of a zigzag traveling wave electro-optic laser modulator usin3 CuCl, KDP Crystal. The inclusion of such practical factors as M/W and optical loss results in an optimum design in which modulator dimensions and bandwidth limitation are uniquely determined by optical and M/W dielectic properties of modulating crystal. The main conclusion of the analysis are: (1) CuCl, KDP may be used to produce 50% modulation over bandwidth of 10(GHz) with less than (watt) of modulating power. (2) The upper modulation frequency limit is set by a cutoff frequency which arises from finite width of optical beam.

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Second-order Nonlinear Optical Properties of Amorphous Molecules Based on 5-(4-Diethylamino-benzylidene)-1,3-dimethyl-pyrimidine-2,4,6-trione

  • Lee, Seung-Mook;Rhee, Bum-Ku;Lee, Sang-Ho;Lee, Chul-Joo;Park, Ki-Hong
    • Journal of Photoscience
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    • v.10 no.2
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    • pp.203-208
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    • 2003
  • Two coupled molecules were successfully synthesized by condensation of amine-donor-substituted barbituric acid derivativies as nonlinear optical chromophores. A flexible spacer of the alkyl chain with different lengths of carbon chains (5 and 6 carbons) was introduced between two chromophores, which prevented crystallization and aggregation of molecules. Two coupled molecules (B-Cn-B, n=5, 6) had glass-transition temperatures on a second heating around 81 and 76$^{\circ}C$ without melting points, respectively. To explore the linear optical properties, thin-films were prepared and examined by a photometry method using Nd:YVO$_4$ CW laser. Also, microscopic and macroscopic nonlinear optical properties were measured by Hyper-Rayleigh Scattering (HRS) and the Maker Fringes method using Nd:YAG ps pulse laser, respectively. In spite of the moderate hyperpolarizabilities of coupled molecules, the second order NLO coefficient (d$\_$33/) was larger than the conventional Disperse Red 1 doped PMMA polymeric system.

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