FIELD EMISSION COLD CATHODE ELECTRON GUN AND MICROWAVE TUBE USING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a field emission cold cathode electron gun which prevents an electron beam from expanding radially and maintains a sufficient electron beam transmittance, while achieving a high DC-RF conversion efficiency. ;SOLUTION: A field emission cold cathode electron gun 100 comprises a field emission emitter array cathode 1 formed by arraying plural field emission cathodes each containing an electron emitting needle and a gate electrode having an opening near the tip of the electron emitting needle, an anode 4 for focusing and accelerating electrons emitted out of each field emission cathode and a magnetic field device 9 composed of the field emission emitter array cathode 1, of magnets 7 generating magnetic fields in parallel with a central axis passing through the centers of acceleration anode 4 and pole pieces 8, where whole or part of a cathode support member 2, holding and fixing the field emission emitter array cathode 1, is made of ferromagnet.;COPYRIGHT: (C)2000,JPO