Effect of gas pressure on permanent dark image sticking on a bright screen in AC plasma-display panels

The permanent dark-image-sticking phenomenon on a bright screen was examined under various gas pressures in a 42-in. ACPDP with an He(35%)-Xe(11%)-Ne gas composition. Infraredemission observations reveal that the discharge characteristics related to the MgO surface are almost the same in both the discharge and non-discharge cells, whereas luminance observations show a deterioration in the visible-conversion characteristics related to the phosphor layer in both the discharge and non-discharge cells. Consequently, the permanent dark-image-sticking phenomenon on a bright screen is found to be strongly related to the deposition on the phosphor layer to theMg species sputtered from the MgO surface due to a repetitive strong sustain discharge. For a decrease in gas pressure, the permanent dark image sticking on a bright screen became wore due to a severe degradation of the visible-conversion characteristics of the phosphor layer caused by the deposition of higher amounts of sputtered Mg species on the phosphor layer, as confirmed by various measurements, such as V^t closed curves, time-of-flight secondary-ion mass spectrometry, photoluminescence, and atomic-force-microscope analyses.