Panel including a transparent front plate and a rear plate that leave between them discharge spaces, the walls of which are at least partly coated with a layer of a phosphor capable of emitting green, blue or red light; the green phosphor is formed from a mixture of two aluminates having a spinel structure, one A doped with manganese and the other B doped with cerium and with terbium; preferably, the blue phosphor is based on an aluminate of the same structure. The static charges of the various phosphors are homogenized and the risks of phosphor performance degradation during manufacture of the panel are limited.