DIFF Subgroup Additional Only
H01J 2237/182 Obtaining or maintaining desired pressure
Full Title
Discharge tubes exposing object to beam, e.g. for analysis treatment, etching, imaging > Vacuum control means > Obtaining or maintaining desired pressure
Of 1 combined children, 0 exist in both systems.
1 codes are CPC-only extensions.
Note: 1 CPC extensions are marked as secondary classification only.