DIFF Subgroup
H01J 1/3042 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 > Cold cathodes, e.g. field-emissive cathode > Field-emissive cathodes
Of 2 combined children, 0 exist in both systems.
2 codes are CPC-only extensions.