Magnetron device having magnetic means for generating a uniform interaction field

A magnetron device for generating a substantially uniform magnetic field which comprises a cathode electrode and an anode electrode disposed concentrically with said cathode electrode so as to jointly constitute a cylindrical electrode assembly;

• a plurality of vanes inwardly projected from the inner surface of said anode electrode;
• a resonance cavity circuit defined by a portion of said anode and vanes and for oscillating electric waves when supplied with the energy of electrons emitted from the cathode electrode;
• an output circuit for drawing out an oscillated output from said resonance cavity circuit;
• and a magnetizing device wherein the mutually facing surfaces of a paired permanent magnets disposed on the opposite sides of the interaction space formed between the cathode and anode are all or partially covered with a soft magnetic member, thereby controlling the orbit through which electrons emitted from the cathode electrode revolve about the axis of said cathode electrode, and at least one of the mutually facing magnetic pole surfaces of said paired permanent magnets is fitted with an annular magnetic member, the inner peripheral wall of which has its inner surface shaped concave.

A magnetron device for generating a substantially uniform magnetic field which comprises a cathode electrode and an anode electrode disposed concentrically with said cathode electrode so as to jointly constitute a cylindrical electrode assembly;

• a plurality of vanes inwardly projected from the inner surface of said anode electrode;
• a resonance cavity circuit defined by a portion of said anode and vanes and for oscillating electric waves when supplied with the energy of electrons emitted from the cathode electrode;
• an output circuit for drawing out an oscillated output from said resonance cavity circuit;
• and a magnetizing device wherein the mutually facing surfaces of a paired permanent magnets disposed on the opposite sides of the interaction space formed between the cathode and anode are covered with materials which present a progressively smaller magnetic permeability as they approach the center of the magnetic pole surface, thereby controlling the orbit through which electrons emitted from the cathode electrode revolve about the axis of said cathode electrode.