METAL CATHODE FOR ELECTRON TUBE AND HEAT RADIATION TYPE CATHODE STRUCTURE WITH THE SAME

摘要

PURPOSE: A metal cathode for an electron tube and a heat radiation type cathode structure with the same are provided , which has a high capacity of emitting electronics and a long life, so is can be used in a large electron tube and high definition electron tube. CONSTITUTION: The metal cathode is composed Pt group elements of 80-95wt% such as Pt, Pd, Ir, and Ba of 5-20wt%. Further, the metal cathode may further comprise at least one rare earth element. The heat radiation type cathode structure comprises such metal cathode. It is preferable that the metal cathode(11) is welded to an upper part of a sleeve(15) having a heater(13) embedded to be used as hot electron emission material.