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Publication of NL132318CpublicationCriticalpatent/NL132318C/xx
H01J41/00—Discharge tubes for measuring pressure of introduced gas or for detecting presence of gas; Discharge tubes for evacuation by diffusion of ions
H01J41/12—Discharge tubes for evacuating by diffusion of ions, e.g. ion pumps, getter ion pumps
H01J41/18—Discharge tubes for evacuating by diffusion of ions, e.g. ion pumps, getter ion pumps with ionisation by means of cold cathodes
H01J41/20—Discharge tubes for evacuating by diffusion of ions, e.g. ion pumps, getter ion pumps with ionisation by means of cold cathodes using gettering substances