Electron beam-generating device, and image-forming apparatus and recording apparatus employing the same

An electron beam-generating device comprising a plurality of electron-emitting units, each electron emitting unit including an electron-emitting element and a modulation electrode for modulating an electron beam emitted from the electron-emitting element,

• the electron-emitting elements and the modulation electrodes of the electron emitting units being arranged on a same surface of a substrate, or the modulation electrodes being placed on a reverse surface of the substrate to the surface bearing the electron-emitting elements,
• wherein the electron-emitting element of each electron emitting unit comprises an electron emitting portion, a higher potential electrode on one side of the electron emitting portion and a lower potential electrode on a side of the electron emitting portion opposite the one side, wherein the lower potential electrode extends further than the higher potential electrode;
• and
• the modulation electrode of each electron emitting unit is placed only on the one side of the higher potential electrode of the electron emitting unit.

An electron beam-generating device comprising:

• an electron-emitting element and a modulation electrode for modulating an electron beam emitted from the electron-emitting element,
• the modulation electrode being provided on a reverse surface of a substrate to a surface bearing the electron-emitting element and formed integrally with the electron-emitting element,
• the distance between the surface of the modulation electrode and the surface of the substrate bearing the electron-emitting element being different between a region under the electron-emitting element and another region;
• and
• the device further comprising means for applying a voltage for converging or diverging a spot diameter of the electron beam concurrently with applying a voltage for modulating the electron beam to the modulation electrode.