An electron emitter includes an emitter layer formed of a dielectric
material, an upper electrode, and a lower electrode. A drive voltage is
applied between the upper electrode and the lower electrode, for emitting
electrons. The upper electrode is formed of scale-like conductive
particles on the upper surface of the emitter layer and has a plurality
of opening portions. The surfaces of overhanging portions of the opening
portions that face the emitter layer are apart from the emitter layer.
The overhanging portions each have such a cross-sectional shape as to be
acutely pointed toward the inner edge of the opening portion, or the tip
end of the overhanging portion, so that lines of electric force
concentrate at the inner edge.