Indirectly heated filamentary cathode

摘要

An indirectly heated filamentary cathode capable of significantly reducing its resistance, uniformly emitting electrons therefrom and effectively elminating its insulation failure. In the filamentary cathode, a cathode substrate is constituted by a metal conductive layer of a cylindrical shape arranged so as to be contacted with and electrically insulating layer and a fine metal wire wound which are closely contacted together, so that an electron emitting layer may be deposited through the metal conductive layer on the electrically insulating layer.