Patent ID: 8829913
Filing Date: 2014-09-09
Classification: G01N

Abstract:
1. A discharge ionization current detector for ionizing and detecting a sample component in a sample gas where the sample gas is ionized using plasma created by discharge, comprising: a) a plasma generation means for generating a dielectric barrier discharge by a low-frequency AC electric field within a gas passage in which a plasma gas flows, so as to create plasma from the plasma gas by the dielectric barrier discharge; b) a sample-gas introduction passage for introducing a sample gas into the gas passage; c) an ion-collecting electrode located within the gas passage, for, detecting an ion current originating from a sample component in the sample gas ionized by an action of light emitted from the plasma created by the plasma generation means; d) a dummy electrode located within the gas passage at such a position where the light emitted from the plasma reaches while neither the sample gas nor a component in the sample gas passes by; and e) a differential detection means for determining a differential signal between a detection signal obtained with the ion-collecting electrode and a detection signal obtained with the dummy electrode.