Measurement of excited Xe atoms density in alternating current plasma display panel by means of laser absorption spectroscopy

The exited Xe atoms in the 1s₅ metastable state and the 1s₄ resonance state across the two sustaining electrode have been monitored in a micro-discharge cell of alternating current plasma display panels (PDPs) by laser absorption spectroscopy. In this study, it is found that the maximum excited xenon density is 5.4×10¹² cm^-3 in the 1s₅ metastable state and 1.2×10¹² cm^-3 in the 1s₄ resonance state for the PDP cell with gap distance of 150μm and width of 350μm under the fixed gas pressure of 350 torr and a mixture of Xe content ratio of 10% with Ne under driving frequency of 35 kHz. It is also observed that the exited Xe atom density and the plasma ion density are strongly correlated with one another in this experiment. It is noted that the plasma ion density reaches a minimum at the center of electrode gap and a maximum of 9.0×10¹¹ cm^-3 in a region located 200 μm away from this center under the filling pressure of 350 torr, which corresponds to the strongest discharge in alternating current plasma display panel (ac-PDP). When increasing PDP driving frequency from 35 kHz, 50 kHz up to 100 kHz, it is found that density of excited Xe atom in the 1s₅ metastable state increase from 6.5×10¹² cm^-3 up to 1.39×10¹³ cm^-3.