• Title/Summary/Keyword: blue phosphor

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Electrical and Optical Property of Powder Electroluminescent device at Dielectric variety (절연체 종류에 따른 후막 전계 발광소자의 광학 및 전기적 특성)

  • Oh, Joo-Youl;Lee, Jong-Chan;Park, Dae-Hee
    • Proceedings of the KIEE Conference
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    • 1999.07d
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    • pp.1800-1802
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    • 1999
  • Electroluminescence is occurred when phosphor is located in electric field. In this paper, we made powder electroluminescent device (PELD) with structured ITO film/phosphor/Insulator/silver paste. The transparent electrode was ITO film and green(2704-01) and orange(2702-02) and blue-green(2703-01) were used as phosphor. The insulator was $BaTiO_3$ and $Y_2O_3$, back electrode was silver paste. To investigate electrical and optical properties of PELDs, EL spectrum, Brightness, Transferred charge density using Sawyer-Towers circuit was measured.

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Combinatorial Synthesis and Screening of the $Eu^{2+}$-activated Phosphors for LED in the System CaO-$Al_2O_3-SiO_2$

  • Park, Seung-Hyok;Yoon, Ho-Shin;Kim, Chang-Hae;Jang, Ho-Gyeom
    • 한국정보디스플레이학회:학술대회논문집
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    • 2004.08a
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    • pp.647-649
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    • 2004
  • We have synthesized phosphor in the system CaO-$Al_2O_3-SiO_2$ by combinatorial polymerized-complex method. The application of combinatorial synthesis and characterization of luminescent materials has been enlarged to identification and optimization in interesting new phosphor. In this study, we investigated luminescent properties of above-mentioned materials by excitation and emission spectra. In $Eu^{2+}$ activated $Ca_1Al_2Si_2O_8$ phosphor emit the blue light.

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A Study on the Phosphorescent Characteristics of Blue $\textrm{Ca}\textrm({Al}_{0.97}\textrm{B}_{0.03})_2\textrm{O}_4$: $\textrm{Eu}^{+2},\;\textrm{Nd}^{+3}$ Phosphor (청색 $\textrm{Ca}\textrm({Al}_{0.97}\textrm{B}_{0.03})_2\textrm{O}_4$: $\textrm{Eu}^{+2},\;\textrm{Nd}^{+3}$ 형광체의 잔광 특성에 관한 연구)

  • Kim, Dae-Su;Lee, Im-Ryeol
    • Korean Journal of Materials Research
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    • v.9 no.1
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    • pp.3-7
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    • 1999
  • The change of phosphorescent property with chemical modification and co-doping of Nd as an auxiliary activator in CaAl$_2$$O_4$: Eu\ulcorner, Nd\ulcorner phosphor, employing Nd\ulcornerion(0.6%) and an co-activator maintained its afterglow for 4.5 hours. And also the initial persistent brightness and phosphorescent property were further improved both by substituting Al by B atoms and incorporation of Nd\ulcorner ion. It was found that the persistent time was 30 hours for&Ca(Al_{0.97}\;B_{0.03}) $_2$$O_4$:EU\ulcorner(0.3%), Nd\ulcorner(0.6%) phosphor.

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Studies on Eu doping effect on $CaAl_2O_4:\;Eu^{2+}$ phosphor material

  • Bartwal, Kunwar Singh;Ryu, Ho-Jin
    • Proceedings of the Korean Society Of Semiconductor Equipment Technology
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    • 2007.06a
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    • pp.188-192
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    • 2007
  • High brightness and long persistent luminescence phosphor $CaAl_2O_4:Eu^{2+}$ was prepared with varying $Eu^{2+}$ concentration by solid state reaction technique. Synthesized materials were investigated by powder X-ray diffractometer (XRD), SEM, TEM, photoluminescence excitation and emission spectra. Broad band UV excited luminescence of the $CaAl_2O_4:Eu^{2+}$ was observed in the blue region (${\lambda}_{max}\;=\;440\;nm$) due to transitions from the $4f^65d^1$ to the $4f^7$ configuration of the $Eu^{2+}$ ion. The decay time of the persistence indicated that the persistent luminescence phosphor has bright phosphorescence and maintains a long duration. These materials have great potential for outdoor night time displays.

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Luminescence properties of Eu- and Mn-activated $BaMgP_2O_7$ as a potential red phosphor for white emission

  • Kim, Yong-Kwang;Choi, Sung-Ho;Jung, Ha-Kyun
    • 한국정보디스플레이학회:학술대회논문집
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    • 2008.10a
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    • pp.581-584
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    • 2008
  • $BaMgP_2O_7$:Eu,Mn phosphors for white emission were synthesized and their luminescent properties were investigated under UV excitation. The phosphor emits two colors: a blue band by $Eu^{2+}$ and a red band by $Mn^{2+}$. Due to the efficient energy transfer from $Eu^{2+}$ to $Mn^{2+}$, the red emission positioned at 615 nm is greatly enhanced with increasing $Mn^{2+}$ content up to 17.5 mol%.

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Synthesis and Characterization of $Eu^{2+}$ Doped $BaAl_2S_4$ Phosphor by Vacuum Heat Treatment

  • Cho, Yang-Hwi;Park, Do-Hyung;Ahn, Byung-Tae
    • 한국정보디스플레이학회:학술대회논문집
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    • 2006.08a
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    • pp.39-42
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    • 2006
  • A $Eu^{2+}$ doped $BaAl_2S_4$ phosphor was synthesized from BaS, EuS, Al and S powder by vacuum heat treatment. The synthesized powder at $850^{\circ}C$ was composed of only $BaAl_2S_4$ phase. The photoluminescence of $Eu^{2+}$ doped $BaAl_2S_4$ phosphor showed the blue emission centered at 470nm and CIE color coordinate at x=0.12, y=0.11.

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Mechanism of Energy Transfer and Improvement Moist Stability of BaMg$Al_{10}O_{17}$:$Eu^{2+}$, $Mn^{2+}$ Phosphor

  • Liu, Ru-Shi;Ke, Wei-Chih
    • 한국정보디스플레이학회:학술대회논문집
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    • 2009.10a
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    • pp.235-238
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    • 2009
  • BaMg$Al_{10}O_{17}$ (BAM) co-doped with $Eu^{2+}$ and $Mn^{2+}$ was synthesized in a solid-state reaction and their luminescence properties were investigated as functions of the concentrations of the sensitizer and activator. BAM:$Eu^{2+}$ had a broad blue emission band at 450 nm and BAM:$Mn^{2+}$ exhibited green emission at 514 nm. The energy transfer from $Eu^{2+}$ to $Mn^{2+}$ was mainly of the resonance-type via an electric dipole-quadrupole interaction. Additionally, the addition of various fluxes such as $AlF_3$ and $BaF_2$ in the synthesis improves the moist and thermal stability. This is particularly important for the phosphor in white light emitting diodes (LEDs).

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Remote Phosphor with Array of Blue Light-emitting Diodes on Board Used in Liquid-crystal Backlight Module

  • Huang, Hsin-Tao;Tsai, Chuang-Chuang;Huang, Yi-Pai;Lin, Jeremy;Chang, Wen-Chi
    • 한국정보디스플레이학회:학술대회논문집
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    • 2009.10a
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    • pp.79-82
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    • 2009
  • This work presents a novel lighting technology based on a YAG:$Ce^{3+}$ phosphor converter with micro line lenticular structure, to accompany an array of bare LED chips on a board. This technology is especially effective in TFT-LCD backlight applications as it offers the advantages of high light radiation efficiency, low color deviation, uniform luminance distribution and compact backlight thickness. Additionally, the proposed configuration is low-cost, can be manufactured quickly, and can be mass-produced economically.

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Transferred charge density and Optical Property on Powder Electroluminescent device (후막 EL 소자의 광학 및 이동전하밀도 특성)

  • 오주열;이종찬;박대희
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1999.05a
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    • pp.286-290
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    • 1999
  • Electroluminescence is occurred when phosphor is located in electric field. In this paper, we made powder electroluminescent device (PELD) with structured ITO film/Phosphor/Insulator/Silver paste. The transparent electrode was ITO film and green(2704-01), orange(2702-02) and blue-green(2703-01) were used as phosphor. The insulator was BaTiO$_3$ and $Y_2$O$_3$, back electrode was silver paste. To investigate electrical and optical properties of PELDs, EL spectrum, Brightness, Transferred charge density using Sawyer-Tower\`s circuit was measured.

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Properties of Powder Electroluminescent Device with $Y_2O_3 and BaTiO_3$ (유전체 종류에 따른 후막 전계발광(EL) 소자의 특성)

  • 이종찬;박춘배;박대희
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1999.11a
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    • pp.582-585
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    • 1999
  • Electroluminescence is occurred when phosphor is located in electric field. In this paper, we made powder electroluminescent device (PELD) with structured ITO film/Phosphor/Insulator/Silver paste. The transparent electrode was ITO film and green(2704-01) and orange(2702-02) and blue-preen(2703-01) were used as phosphor. The insulator was BaTiO$_3$ and $Y_2$O$_3$, bark electrode was silver paste. To investigate electrical and optical properties of PELDs, EL spectrum, Brightness . Transferred charge density using Sawyer-Towers circuit was measured.

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