Each of the red, green and blue column electrodes has widened portions each having a row-direction width larger than that of the other portions. Each of the widened portions faces a head portion of each of the transparent electrodes of a pair of row electrodes constituting each row electrode pair. The widened portion of the green column electrode facing the green discharge cell provided with the green phosphor layer is located in a different position in the column direction from a position of each of the widened portions of the red and blue column electrodes respectively facing the red and blue discharge cells respectively provided with the red and blue phosphor layers.