Klystron device

A klystron device comprising:

• a klystron body having an electron gun section that generates an electron beam, a collector section that captures the electron beam, a plurality of cavity resonators arranged between the electron gun section and the collector section, and a plurality of drift tubes that connect the plurality of cavity resonators in an axial direction;
• and a focusing magnetic field device to focus the electron beam,
• wherein
• the cavity resonators have nose sections that face each other in the axial direction and form a gap section that is connected to the drift tubes,
• at least one of the cavity resonators has an electric field correction section in a part of the nose section that makes a space of the gap section different with respect to a space between the nose sections, and
• the electric field correction section
• protrudes from the nose section in a radial direction of the cavity resonator and reduces the space of the gap section,
• is recessed from the nose section in a circumferential direction of the cavity resonator and increases the space of the gap section, or
• protrudes from the nose section in the radial direction of the cavity resonator to reduce the space of the gap section, and is recessed from the nose section in the circumferential direction of the cavity resonator to increase the space of the gap section.