Directly heated cathode structure

Directly heated cathode structure

Directly heated cathodes

Directly heated meshed cathode for electronic tubes and method o

Directly heated oxide cathode

Directly heated oxide cathode and production thereof

Directly heated thermionic flat emitter

Directly heated type oxide cathode

Directly-heated cathode structure

Directly-heated cathodes

Directly-heated oxide cathode and fluorescent display tube...

Discharge device having cathode with micro hollow array

Discharge electrode for use in an electrostatic precipitator...

Discharge electrode structure

Discharge lamp and method of making same

Discharge lamp having an electrode body with a hermetically...

Dispenser cathode

Dispenser cathode

Dispenser cathode

Dispenser cathode