An image display device in which each pixel has a thin-film electron
source composed of a lower electrode (which is a signal wire), an
electron accelerating layer (which is formed by anodizing the surface of
said signal wire), and an upper electrode (which covers said electron
accelerating layer and releases electrons), in which the anodized film
constituting said electron accelerating layer contains hydrated alumina
component and anhydrous alumina component such that their ratio in the
side close to the upper electrode is greater than that in the side close
to the lower electrode. This structure prevents said thin-film electron
source from being deteriorated in diode characteristics by said electron
accelerating layer, thereby enhancing the reliability of said image
display device.