To provide an electron-emitting apparatus which has a simple power supply and is capable of avoiding unnecessary power consumption thereof.
An electron-emitting element 10 has; an electron emission unit EP including a lower electrode 12, an emitter section 13 composed of a dielectric material, and an upper electrodes 14 having a plurality of micro through holes; and a power supply 30 for applying a power supply voltage to the electron emission unit. During the period between the point at which emission of electrons accumulated in the emitter section is started and the point at which the electron emission is completed, the power supply generates a first power supply voltage AC 210(V) as power supply voltage, whose absolute value changes with forming a sinusoidal wave so that the potential of the upper electrode is higher than the potential of the lower electrode. During the period between the point at which the electron accumulation in the emitter section is started and the point at which the electron accumulation is completed, the power supply generates a second power supply voltage AC 50(V) as power supply voltage whose absolute value increases with forming a sinusoidal wave so that the potential of the lower electrode is higher than the potential of the upper electrode.
AKAO TAKAYOSHI
KAMECHI TETSUJI
NAKAMURA HIROKAZU
