Patent ID: 6388379
Filing Date: 2002-05-14
Classification: H01J

Abstract:
A magnetron comprising a hollow cylindrical anode, and a cathode assembly co-axially surrounded by the anode, said cathode assembly comprising:a cylindrical secondary-electron emitter co-axial with the anode; at least one field-electron emitter provided with a respective sharpened working end-face; and a pair of focusing shields located on end-faces of the cathode assembly and defining, together with the anode and the secondary-electron emitter, an evacuated resonant cavity; at least one of said focusing shields being electrically isolated from the secondary-electron emitter, and said at least one field-electron emitter being located on an inner surface of said at least one focusing shield within the evacuated resonant cavity with said respective sharpened working end-face adjacent to and spaced from an outer surface of the secondary-electron emitter.