IMPREGNATED FILAMENTARY CATHODE Russian patent published in 2007 - IPC H01J19/08 

FIELD: electronic engineering, filamentary cathodes for electron devices.

SUBSTANCE: proposed impregnated filamentary cathode has heater and emitter directly mounted on the latter and made of porous tungsten layer impregnated with thermionic material. Heater working medium is wire (rod) made of one of following high-melting materials W, No, or those alloyed with Re; mentioned wire or rod is cut along its axis across diameter or segment; emitter material is applied to flat surface of wire formed on its longitudinal cut. Filamentary cathode can be made in the form of Archimedean or cylindrical spiral, or in the form of T- or U-shaped curves, or else in the form of straight line or circle.

EFFECT: enhanced reliability of emitter material adhesion to heater surface and enhanced operating capacity of emitter at relatively low heating temperatures.

2 cl, 3 dwg