DIFF Subgroup
H01J 21/36 Tubes with flat electrodes, e.g. disc electrode
Introduced: September 1968
Full Title
Full titles differ between systems:
IPC:
Vacuum tubes > Tubes with flat electrodes, e.g. disc electrode
CPC:
Vacuum tubes (H01J25/00, H01J31/00 - H01J40/00, H01J43/00, H01J47/00, H01J49/00 take precedence; details of vacuum tubes H01J19/00) > Tubes with flat electrodes, e.g. disc electrode
No child classifications to compare. This is a leaf node in both IPC and CPC.