Impregnated cathode

摘要

An impregnated cathode having a complex porous body of one-body construction which is mounted in a metal sleeve and in which a partition layer made of a porous material having a porosity less than 17% is arranged in close contact with an impregnated layer made of a porous material containing an electron emissive material. The aforementioned porous partition layer takes the place of the conventional partition plate of refractory metal. The impregnated cathode according to the present invention can not only have its size reduced without any difficulty but also enjoy a high emission current density with a remarkably small dispersion.