• Title/Summary/Keyword: Phosphor layer

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Luminescence Properties of Phosphor Layer with Discharge Conditions in AC PDP (교류형 플라즈마 디스플레이 패널의 방전 조건변화에 따른 형광막의 발광특성)

  • Jang, Sang-Hun;Tae, Heung-Sik;Choe, Gyeong-Cheol
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.48 no.10
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    • pp.704-709
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    • 1999
  • The optical properties such as luminance and color coordinates for phosphor layer were studied with applied voltage and gas pressure, Xe mixing ratio, frequency using He and Xe mixing gas in chamber like AC PDP. The luminance of red phosphor layer at constant pressure(300Toor) is increased with increasing voltage, but color purity is not varied. The luminance of red phosphor layer at constant voltage(280V)is decreased with increasing pressure, but the color purity is not varied. But the luminance is increased with increasing Xe mixing ratio at constant pressure(200Toor). And also the color purity is improved by this process. The luminance is increased up to 40kHz, but the color purity with frequency is not varied.

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Effects of Phosphor Layer Morphology on Discharge Characteristics of Red, Green, and Blue Cells in AC-PDP

  • Lee, Jae-Jin;Jang, Sang-Hun;Tae, Heung-Sik;Choi, Kyung-Cheol
    • Journal of Information Display
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    • v.2 no.4
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    • pp.52-56
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    • 2001
  • This paper presents the effects of the phosphor layer morphology related to the discharge volume on the discharge and radiation characteristics of the Red, Green, and Blue cells in an AC-PDP. As the thickness of the phosphor layer increases and the corresponding discharge volume in the cells decreases, the voltage margin decreases due to an increase in the sustain voltage. In contrast, the IR(Infrared) emission, discharge current, and luminance characteristics remain almost unchanged, regardless of any changes in the phosphor layer morphology.

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Bi-layers Red-emitting Sr2Si5N8:Eu2+ Phosphor and Yellow-emitting YAG:Ce Phosphor: A New Approach for Improving the Color Rendering Index of the Remote Phosphor Packaging WLEDs

  • Nhan, Nguyen Huu Khanh;Minh, Tran Hoang Quang;Nguyen, Tan N.;Voznak, Miroslav
    • Current Optics and Photonics
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    • v.1 no.6
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    • pp.613-617
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    • 2017
  • Due to optimal advances such as chromatic performance, durability, low power consumption, high efficiency, long-lifetime, and excellent environmental friendliness, white LEDs (WLEDs) are widely used in vehicle front lighting, backlighting, decorative lighting, street lighting, and even general lighting. In this paper, the remote packaging WLEDs (RP-WLEDs) with bi-layer red-emitting $Sr_2Si_5N_8:Eu^{2+}$ and yellow-emitting YAG:Ce phosphor was proposed and investigated. The simulation results based on the MATLAB software and the commercial software Light Tools indicated that the color rendering index (CRI) of bi-layer phosphor RP-WLEDs had a significant increase. The CRI had a considerable increase from 72 to 94. In conclusion, the results showed that bi-layer red-emitting $Sr_2Si_5N_8:Eu^{2+}$ and yellow-emitting YAG:Ce phosphor could be a prospective approach for manufacturing RP-WLEDs with enhanced optical properties.

Development of yellow and blue phosphor and their emission properties

  • Park Soo-Gil;Cho Seong-Ryoul;Son Won-Ken;Lim Kee-Joe;Lee Ju-Seong
    • Journal of the Korean Electrochemical Society
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    • v.1 no.1
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    • pp.24-27
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    • 1998
  • Electroluminescence (EL) comes from the light emission obtained by the electrical excitation energy passing through a phosphor layer undo. an applied high electrical field $(10^6 V/cm)$. The preparation of white and blue phosphors and characterizations of light emitting alternating current powder electroluminescent devices (ACPELDs) were investigated. In this work, we fabricated two kinds of ELDs, that is, yellow electroluminescent device (B-ELD), blue electroluminescent device (B-ELD). The basic st.uctures of Y-ELD and B-ELD are ITO (Indium Tin Oxide)/phosphor layer/Insulator layer/Carbon electrode and ITO/Phosphor layer/Insulating layer/carbon electrode, respectively. Another structures of ITO/Phosphor and Insulator mixture layer/Backelectrode are introduced. EL spectra and luminance of two types of ELDs were measured by changing voltage at fixed frequency 0.4kHz, 1.5kHz. Blue and yellow phosphors prepared in this work show $50cd/m^2\;and\;30cd/m^2$ of luminance at 400Hz, 150V.

Developments of Transparent ac-PDPs

  • Choi, Hak-Nyun;Lee, Seog-Young;Kim, Yong-Seog
    • 한국정보디스플레이학회:학술대회논문집
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    • 2008.10a
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    • pp.1621-1624
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    • 2008
  • Transparent ac-PDP test panel was prepared via a combination of materials including ITO sustaining electrodes, thin film dielectric layer and nano-sized phosphor powders. The thin film dielectric layer was prepared by E-beam evaporation process and phosphor layer was deposited on metal mesh pattern by electrophoretic deposition process. The optical transmittance and luminance of the panel indicated that full color transparent ac-PDP is feasible with the approach.

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Emission Properties of P-ELD by Thickness of Phosphor and Insulating layer (절연층 두께 변화에 따른 분산형 ELD의 발광특성)

  • 박수길;조성렬
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1999.11a
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    • pp.520-524
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    • 1999
  • Light-emitting diode(LEDs), diode arrays, and phosphor display panels are finding increased use in a variety of commercial applications. Present and anticipated application of these devices include solid state indicator and display systems. In this work, Phosphor based on ZnS:Cu are used. Relation by luminance with the thickness of insulating layer and phosphor layer are discussed. Increased thickness of insulating layer are stable on voltage to 300V. By considering thickness and voltage, optimal structure and thickness are investigated. In order to maximize even surface emission, various sieving processes are introduced. 150cd/m$^2$ luminance by various wave intensity are investigated in stable voltage and frequency.

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The Development of ITO Paste for VPT Phosphor Screen Manufacture (VPT 형광막 제조용 ITO Paste의 개발)

  • Lee, Mi-Young;Woo, Jin-Ho;Kim, Young-Bea;Nam, Su-Yong;Lee, Sang-Nam;Moon, Myung-Jun
    • Journal of the Korean Graphic Arts Communication Society
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    • v.22 no.2
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    • pp.73-82
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    • 2004
  • A thermal transfer method was developed novel method to form the phosphor screen for monochrom VPT. This method have advantages of simple process, clean environment, saving raw material and running-cost. But now applying phosphor screen for thermal transfer method has been formed three layers (phosphor layer, ITO layer and thermal adhesive layer) on the PET film as substrate. This is complex process, consumption of raw-material and require of high cost. Also ITO paste at present has been imported from Japan. To improve these problems, we have developed ITO paste as conductive paste by using ITO sol and binder resin (AA3003). Ito paste as developed in this study has both conductive and excellent thermal transfer abilities. Thus we could manufacture phosphor screen formed two layers (phosphor layer and ITO layer).

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Nano-Sized Phosphor by Reverse Emulsion Process and Precision Nozzle Phosphor Patterning

  • Park, Lee-Soon;Yoon, Hae-Sang;Han, Yoon-Soo;Im, Moo-Sik;Kwon, Young-Hwan
    • 한국정보디스플레이학회:학술대회논문집
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    • 2004.08a
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    • pp.536-539
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    • 2004
  • A novel ink-jet printing method was investigated for fine patterning of phosphor layer in PDP using a precision nozzle printing. A reverse emulsion method was developed for the synthesis of nano-sized phosphor powder that could be formulated in the phosphor ink. The composition of the phosphor ink including charge controlling agents, solvent, dispersant and nano-sized phosphor powder was optimized for the fine patterning of phosphor layer for high resolution PDP.

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Preparation of dense $BaMgAl_{10}O_{17}:Eu^{2+}$ particles and their surface treatment

  • Lee, Dae-Won;Boo, Jin-Hyo;Jung, Ha-Kyun
    • 한국정보디스플레이학회:학술대회논문집
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    • 2005.07b
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    • pp.1499-1502
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    • 2005
  • Dense $BaMgAl_{10}O_{17}:Eu^{2+}$ phosphor particles with a spherical shape have been synthesized through spray pyrolysis method using basic aluminum nitrate precursor as a spray solution. This $BaMgAl_{10}O_{17}:Eu^{2+}$ particles prepared by the spray pyrolysis have shown the stronger emission intensity compared to the commercially-available $BaMgAl_{10}O_{17}:Eu^{2+}$. However, thermal stability of the BAM:Eu b lue phosphor is very poor due to changing from $Eu^{2+}$ to $Eu^{3+}$ at the thermal process, so brightness of the phosphor decreases. To improve the thermal stability of the dense BAM:Eu phosphor, the spherical BAM:Eu particles were coated with pure $BaMgAl_{10}O_{17}$ layer using the hydrolysis reaction in a solution system. The synthesized powders were characterized by XRD, SEM and PL. On the other hand, the emission properties of the BAM:Eu phosphors coated with $BaMgAl_{10}O_{17}$ layer before and after thermal treatment at $500^{\circ}C$ for 30 min were estimated under VUV excitation. The brightness of the coated phosphor was higher than that of the uncoated phosphor. Also, the coating thickness of BAM layer in the BAM:Eu particles was optimized.

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The dark-current and X -ray sensitivity measurement of hybrid digital X-ray detector having dielectric layer structure (a-Se 기반의 혼합형 X-선 검출기에서 유전층의 누설전류 저감효과)

  • Seok, Dae-Woo;Park, Ji-Koon;Joh, Jin-Wook;Lee, Dong-Gil;Moon, Chi-Woong;Nam, Sang-Hee
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.05b
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    • pp.31-34
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    • 2002
  • In this paper, the electric properties of amophous selenium multilayer samples has been investigated. In order to develop the hybrid flat-panel digital· X-ray image detector, we measured and analyzed their performance parameters such as the X -ray sensitivity and dark-current for a amophous selenium multilayers X-ray detector with a phosphor layer, The hybrid digital X-ray image detector can be constructed by integrating a phosphor layer (or a scintillative layer) that convert X-ray to a light on a-Se photoconduction mulilayers that convert a light to electrical signal. As results, the dielectric materials such as parylene between the phosphor layer and the top electrode may reduce the dark-current of the samples. Amorphous selenium multilayers having dielectric layer(parylene) has characteristics of low dark-current, high X-ray sensitivity. So we can acquired a enhanced signal to noise ratio. In this paper offer the method can reduce the dark-current in the hybrid X-ray detector.

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