MAGNETIC PERIODIC FOCUSING SYSTEM Russian patent published in 2023 - IPC H01J23/87 

FIELD: vacuum microwave devices.

SUBSTANCE: invention relates to magnetic periodic focusing systems (MPFS). In a magnetic focusing periodic system consisting of alternating axially magnetized magnets, pole pieces with hubs and magnetic screens made of ferromagnetic material, the end wall of the magnetic screen on the side of the electron gun is made of non-magnetic material, and in the axial direction the end wall is connected to a hollow cylinder made of ferromagnetic material located on the side of the periodic system and having a length l_sh≥l_m, where l_m is the longitudinal dimension of the first magnet located between the pole pieces behind the end wall of the magnetic screen of the electron gun. Pole pieces with the same outer diameter, located on both sides of the first magnet in the area of the electron gun, are made in the form of stepped bodies of revolution from two cylindrical parts. The pole piece located in front of the first magnet does not have a hub and is fixed on one side in the end wall of the magnetic screen of one of the cylindrical parts, and the pole piece located after the first magnet has a one-sided hub oriented towards the center of the periodic system.

EFFECT: improvement in the current flow of the electron flow, a decrease in the thermal load on the slow-wave structure and an increase in the output power level of the microwave device while maintaining the dimensions.

1 cl, 2 dwg