• Title/Summary/Keyword: Phosphors

Search Result 602, Processing Time 0.028 seconds

Composition-tunable emission colors of nitride phosphors

  • Xie, Rong-Jun;Hirosaki, Naoto;Takeda, Takashi
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2009.10a
    • /
    • pp.50-51
    • /
    • 2009
  • Nitride Phosphors have recently been considered as a novel class of luminescent materials for white LEDs due to their promising luminescent properties. It is of great importance to tailor the emission color in order to meet the requirements for practical applications. The paper presents the results of tuning the emission colors of sialon phosphors through compositional tailoring.

  • PDF

Synthesis of Sulfide-based Phosphors by Multiply Combined Methods Based Upon Inorganic Chemistry

  • Kakihana, Masato;Petrykin, Valery
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2009.10a
    • /
    • pp.121-124
    • /
    • 2009
  • We developed a panel of innovative solution-based approaches for synthesis of multicomponent sulfide phosphor materials. The application of these synthesis strategies allowed for preparation of high-purity and high-brightness $BaAl_2S_4:Eu$ and $Ba_2SiS_4:Eu$ phosphors and led to the discovery of new phosphors suitable for application in the LED-based lighting including $Sr_2ZnS_3:Eu$, $CaBaSiS_4:Eu$ and $(Ba,Sr)_2ZnS_3:Eu$.

  • PDF

Recent Progress in the Development of Organometallic Complexes, Inorganic Phosphors and Quantum Dots for White Light Emitting Devices

  • Raja, Inam ul Haq;Lee, So-Ha
    • Journal of the Korean Applied Science and Technology
    • /
    • v.25 no.2
    • /
    • pp.175-195
    • /
    • 2008
  • Recent years have brought remarkable developments in white light emitting devices (WLEDs) and white organic light-emitting devices (WOLEDs). However, their efficiency, CIE values, CRI and lifetime are still not ideal. This review covers detailed discussion about syntheses of organometallic complexes, inorganic phosphors and quantum dots used in WLEDs, WOLEDs and their electroluminescent properties until December 2007.

Highly Reliable White LEDs Using Nitride Phosphors

  • Xie, Rong-Jun;Hirosaki, Naoto;Takeda, Takashi
    • Journal of the Korean Ceramic Society
    • /
    • v.49 no.4
    • /
    • pp.375-379
    • /
    • 2012
  • Nitride phosphors are now attracting significant attention of material scientists and phosphor engineers, because they promise red-shifted photoluminescence spectra, small Stokes shift, high quantum efficiency and low thermal degradation. A number of interesting nitride phosphors have been developed and practiced for producing white light with LED chips. In this paper, the applications of nitride phosphors in highly reliable wLEDs will be overviewed.

Photo- and Cathod-luminesent Properties of $YNbO_4$ : Bi Phosphors ($YNbO_4에\;Bi^{3+}$가 도핑된 형광체의 빛발광 및 저전압 음극선발광 특성)

  • 한정화;김현정;박희동
    • Journal of the Korean Ceramic Society
    • /
    • v.35 no.3
    • /
    • pp.245-250
    • /
    • 1998
  • Field emission display (FED) is currently being explored as a potential flat panel display technology. The need of new materials for low voltage blue phosphors for FED focused our attention on the $Y_2O_3-Nb_2O_5$ sys-tem. Yttrium niobate doped with $Bi^{3+}$ was prepared by solid state reaction technique and the optimization of the luminescent properties with a control of $Bi^{3+}$ amounts and Y/Nb ratio was studied. Under 254 nm and low voltage electron excitations $Bi^{3+}-activated$ YNbO4 phosphors showed a strong and relatively narrow blue em-ission band with a range of 420 to 450 nm, Especially 0.4wt% $Bi^{3+}\;doped\;YNbO_4$ phosphors with Y/Nb ratio of 1/1 showed the maximum emission intensity. Under low voltage electron excitation maximum emission in-tensity appeared at the Y/Nb ratio of 0.495/0.505.

  • PDF

Nano phosphors for PDP RGB and their PL characteristics

  • Yang, Choong-Jin;Choi, S.D.;Park, E.B.;Park, J.I.;Lee, Y.J.
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2007.08b
    • /
    • pp.1646-1649
    • /
    • 2007
  • RF plasma and aerosol nano process were developedfor a volume production of nanoscale phosphors. R, G, and B PDP phosphors were synthesized and the characteristics were optimized through the proprietary power treatments. PL intensities were confirmed to be enhanced up to 70% of that of present commercial phosphors.

  • PDF

Field emission lamp for LCD backlight based on RGB phosphors and vertically-aligned CNTs

  • Park, Boo-Won;Choi, Nam-Sik;Kim, Sung-Hoon;Jeong, Yun-Tae;Kim, Jong-Su
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2007.08b
    • /
    • pp.1545-1546
    • /
    • 2007
  • Zinc gallate-based RGB phosphors and vertically aligned carbon nanotube emitters are prepared for flat field-emission lamp. The blend phosphors of blue $ZnGa_2O_4$, green $ZnGa_2O_4:Mn^{2+}$ and red $ZnGa_2O_4:Cr^{3+}$ are coated on the front glass, and the carbon nanotubes are chemically bonded on the rear ITO glass as a cathode.

  • PDF

Preparation and Luminescent Properties of SrTiO3 : Al, Pr Red Phosphors for the FED (FED용 Al 및 Pr 첨가 SrTiO3 적색 형광체의 제조와 발광특성)

  • Park, Chang-sub;Lee, Jeng-Un;Yu, Il
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.18 no.9
    • /
    • pp.846-850
    • /
    • 2005
  • [ $SrTiO_3$ ]:Al, Pr red phosphors for FED were synthesized by solid state reaction method. The dependence of their luminescent properties on Sr and Al concentration was investigated. The $SrTiO_3$: Al, Pr phosphors showed the characteristic X-ray diffraction patterns of the perovskite structure. Photoluminescence intensity and lattice constant in $SrTiO_3$: Al, Pr phosphors changed in quite a similar manner with Sr concentration. Photoluminescence intensity increased with increasing lattice constant, and the decrease of photoluminescence intensity and lattice constant occurred in the vicinity of 1 mol Sr concentration.

A Study on the Preparation of $MgB_4O_7$ Thermoluminescent Phosphors and X-ray Dosimetry ($MgB_4O_7$ 열형광체의 제작과 X선의 선량측정에 관한 연구)

  • Song, Jea-Heung;Noh, Kyung-Suk;Lee, Deog-Kyu;Koo, Hyo-Geun
    • Journal of radiological science and technology
    • /
    • v.21 no.2
    • /
    • pp.47-52
    • /
    • 1998
  • Tissue-equivalent $MgB_4O_7$ TL phosphors were prepared and the effects of Lantanides series activators on TLD properties of the phosphors were studied. The glow curve of TLD increased TL intensity and the peak temperature is low that is, the heating rate is $10^{\circ}C/sec$. The activation energy of the main peak estimated by the peak shape method. By these methods, the estimated activation energies were $0.76{\sim}1.55eV$ respectively. The TL phosphors prepared in this work may be utilized to radiation sensor elements because of this high sensitivity to X-ray.

  • PDF

Study on the Rare-earth Phosphors Intensifying Screen (희토류계(稀土類系) 증감지(增感紙)에 관(關)한 연구(硏究))

  • Huh, Joon;Kim, Chang-Kyun
    • Journal of radiological science and technology
    • /
    • v.1 no.1
    • /
    • pp.15-24
    • /
    • 1978
  • The characteristics of the rare earth phosphors intensifying screen (LM-6, Grenex-8) as compared with $CaWO_4$ intensifying screen had been studied utilizing several common x-ray films, and found the following results. 1. Compared with the conventional CaWO4 intensifying screen, the rare earth phosphors intensifying screen was found to be more sensitive over to 1.26-3.47 times. So the radiation exposure could be reduced to 1/1.26 -1/3.47. 2. Sharpness as well as the film speed were both increased. So the motion blurring and geometrical unsharpness could be decreased. 3. In spite of that the film speed was increased, photographic contrast was kept up. Therefore, the more ideal film of greater latitude could be obtained. 4. The effects of the rare earth phosphors intensifying screen would be much increased as using with orthochromatic x-ray films.

  • PDF