Patent ID: 9679755
Date: 2017-06-13
CPC Classifications: H01J

Claim:
1. An ionization apparatus for ionizing predetermined sample molecules or atoms, the ionization apparatus comprising: a) an ionization chamber having: an electron introduction port for introducing thermal electrons to an internal space of the ionization chamber; an electron discharge port for discharging thermal electrons that have passed through the internal space; and an ion emission port for emitting sample-derived ions produced in the internal space to an outside; b) a thermal electron source for producing the thermal electrons, the thermal electron source being arranged on an outer side of the electron introduction port; c) an electron trapping unit for trapping the thermal electrons discharged through the electron discharge port, the electron trapping unit being arranged on an outer side of the electron discharge port; d) a repeller electrode for forming, in the ionization chamber, a repelling electric field that repels the sample-derived ions produced in the ionization chamber toward the ion emission port, the repeller electrode being arranged inside of the ionization chamber so as to be opposed to the ion emission port; and e) an ion focusing electrode for forming, in the ionization chamber, a focusing electric field that focuses the sample-derived ions produced in the ionization chamber around a central axis of an ion flow formed by repelling the sample-derived ions by the repelling electric field, the ion focusing electrode being arranged any one or both of between the thermal electron source and the electron introduction port and between the electron discharge port and the electron trapping unit.