CATHODE FOR ELECTRON TUBE AND METHOD FOR MANUFACTURING THE SAME

摘要

A cathode for an electron tube is described that has little deterioration of emission current after long operation, is used as a long-li fe oxide cathode even with high current density in a CRT, and is economical. An emissive material is adhered onto a substrate that is positioned at o ne opening of a cylindrical sleeve having a built-in heater coil and that includes nickel as a main component by thermally decomposing carbonate including an alkaline earth metal oxide and at least one element selected from the group consisting of titanium, nickel, zirconium, vanadium, niobium and tantalum.