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Your search keyword '"Cheong, Hee Woon"' showing total 29 results
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29 results on '"Cheong, Hee Woon"'

9. Mechanism of high luminous efficacy in plasma display panel with high secondary electron emission coefficient cathode material analyzed through three-dimensional fluid model simulation.

Author

Kwon, Ohyung, Bae, Hyun Sook, Jung, Hae-Yoon, Lee, Tae-Ho, Cheong, Hee-Woon, and Whang, Ki-Woong

Subjects
CATHODES, ELECTRON emission research, ELECTROMAGNETIC fields, MAGNETIC fields, FIELD theory (Physics)
Abstract

The mechanism to realize high luminous efficacy in a plasma display panel fabricated with a cathode material possessing a high secondary electron emission coefficient (γ) for Ne and Xe ions was studied via three-dimensional numerical simulation. When a high γ cathode material is used, the increased electron heating efficacy is responsible for increasing vacuum ultraviolet (VUV) efficacy with 10% Xe content gas. However, the continued availability of sufficient secondary electrons during the dynamic moving phase of the cathode sheath in which the electric field remains weakened causes increasing VUV efficacy with 30% Xe content gas. It was found that the improvement of the luminous efficacy of the plasma display panel with a high γ cathode material is maximized under the condition of high Xe content gas because of the simultaneous increase of the electron heating efficacy and Xe excitation efficacy. [ABSTRACT FROM AUTHOR]

Published
2011
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17. The role of a diffusion barrier in plasma display panel with the high gamma cathode layer

Author

Lee, Tae-Hoo, Cheong, Hee-Woon, Kwon, Ohyung, Whang, Ki-Woong, Steinmuller, Sven Ole, Janek, Jürgen, and Justus Liebig University Giessen

Subjects
SiO(2) diffusion barrier, Plasma display panel (PDP), blocking diffusion of impurities, ddc:540, MgO-SrO double cathode layer, high Xe gases
Abstract

Plasma display panel (PDP) with MgO-SrO double cathode layer and SiO(2) diffusion barrier is proposed to make the SrO layer free of contaminations. Time of flight-secondary ion mass spectrometry (TOF-SIMS) analysis shows the diffusion of impurities, like Na and K, can be effectively blocked while a new SrO layer is formed on top of the MgO layer. This structure shows that high Xe gases can be used to improve the luminous efficacy 2.3 times and decrease the voltage margin more than 10 V compared to the conventional PDP using Ne-Xe 15%. The aging time was also significantly decreased to 3-4 h.

Published
2011
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29. Fast-Addressing Waveform with Negative-Going Ramp for High-Xe PDP with High-Gamma Cathode Materials.

Author

Whang, Ki-Woong, Cheong, Hee-Woon, and Kwon, Ohyung

Subjects
CATHODE rays, DIFFUSION barriers, SEMICONDUCTOR thin films, ENGINEERING design, PLASMA displays, PLASMA engineering
Abstract

In this paper, the address discharge characteristics of high-Xe PDPs with high-gamma cathode materials were investigated. It will be shown that the address discharge characteristics such as the dynamic voltage margin and the address discharge time lag of high-Xe PDP with MgO-SrO double cathode layer and one with MgCaO single cathode layer can be improved by inducing stable, continuous weak discharges during the reset period with a newly designed waveform. The deposition of pure MgO powder on high gamma cathode material has also proved to be effective in reducing the address discharge time lag of high-Xe PDP. [ABSTRACT FROM AUTHOR]

Published
2012
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