Yang Lanlan

Investigation of Anode Striation in 34" VGA Shadow Mask PDP

A macro-cell was used to study the phenomenon of anode striation on a 34 VGA Shadow Mask Plasma Display Panel (SMPDP). The breakdown process in the sustaining period of the macro-cell was taken by an Intensified Charge Coupled Device(ICCD) with narrow band filters. The mechanism of formation and evolution of the anode striation on SMPDP were investigated. The influence of the width of the electrode, the sustaining voltage, sustaining frequency and the voltage of the shadow mask on the anode striation was also studied. The results showed that the width of the electrodes, the sustaining voltage and frequency had a strong influence on the anode striation. The voltage of the shadow mask, however, hardly affected the anode striation, the firing voltage or the sustaining voltage.

Mechanisms of Streamer Propagation Affected by Driven Voltage Polarity in a Cold Atmospheric Pressure Plasma Jet

A two-dimensional self-consistent fluid model is used to investigate the effects of DC-voltage polarity in plasma initiation and propagation of helium plasma jet. The simulation results indicate that the difference in initial breakdown for the positive jet and negative jet leads to a difference in the electron density of about 4 orders of magnitude, even with the same initial electric field, which also influences the subsequent propagation. In the propagation process of negative jets, the ionization process exists in a longer gas channel behind the streamer head. In addition, the drift process to the infinite grounded electrode driven by the electric field results in higher energy consumption in the ionization process. However, in the positive jet, the ionization process mainly exists in the streamer head. Therefore, the differences in the initial breakdown and propagation process make the electric field intensity and the ionization weaker in the streamer head of the negative jet, which explains the weaker and shorter appearance of the negative jet compared to the positive jet. Our model can adequately reproduce the experimental results, viz. a bullet-like propagation in the positive jet and a continuous plasma plume in the negative jet. Furthermore, it also indicates that the streamer velocity shows the same variations as the electron drift velocity for both positive and negative jets.

Study of An Unsymmetrical Shadow Mask PDP with High Luminous Efficacy

A new shadow mask plasma display panel (SMPDP) is presented in this article. The unsymmetrical geometry structure of the discharge cell is its main feature. A macro-cell with a ratio of 40:1 was designed and fabricated. The geometrical parameters and electrodes structure of the discharge cell of the unsymmetrical SMPDP were optimized. Compared with current SMPDP, its luminous efficiency was obviously improved. Then a 32-inch wide video graphics array (WVGA) unsymmetrical SMPDP with a luminous efficacy of 1.8 Lm/W was produced.