Patent ID: 8759759
Filing Date: 2014-06-24
Classification: H01J

Abstract:
1. A linear ion trap analyzer, comprising, an ion trapping volume surrounded by multiple columnar electrodes, wherein a generatrix of the multiple columnar electrodes is parallel to a central axis of the ion trapping volume; a high frequency voltage applied to at least a part of the multiple columnar electrodes to form a trapping electric field in the ion trapping volume; an ejection slot configured to pass ions resonantly ejected from the ion trapping volume perpendicular to the central axis; and a field adjusting electrode opposite the ejection slot and configured to assist ejection of selected ions from the ion trapping volume, wherein, the field adjusting electrode is placed between two of the multiple columnar electrodes or inside the slot in one of the multiple columnar electrodes, and a potential applied to the field adjusting electrode is set as the sum of a portion of the high frequency voltage applied to an adjacent columnar electrode and an adjustable DC voltage offset.