CPC Subgroup
H01J 1/34 Photo-emissive cathodes (H01J1/35 takes precedence)
Full Title
Details of electrodes, of magnetic control means, of screens, or of the mounting or spacing thereof, common to two or more basic types of discharge tubes or lamps (details of electron-optical or ion-optical arrangements H01J3/00) > Main electrodes > Photo-emissive cathodes (H01J1/35 takes precedence)