Patent ID: 8263932
Filing Date: 2012-09-11
Classification: H01J

Abstract:
1. A mass-analyzing method using a multi-turn time-of-flight mass spectrometer having: an ion source; a loop orbit along which a variety of ions departing from the ion source are made to fly once or repeatedly plural times; an ion selector for selecting ions from the ions flying along the loop orbit by allowing a passage of ions along the loop orbit only within a predetermined time range; a dissociation means for dissociating ions deviated from the loop orbit; and a mass analyzing means for mass analyzing product ions generated by the dissociation, the mass-analyzing method comprising: a) a setting step for setting a plurality of masses of ions to be measured; b) an ion selection step for obtaining the predetermined time range for each of the plurality of masses set in the setting step and for operating the ion selector so as to allow the passage of ions only within the predetermined time range and thereby select, on the loop orbit, each of the ions having the set plurality of masses; c) a deviation timing determination step for obtaining deviation timings at which different kinds of ions are not mixed when the ions having the set plurality of masses are deviated from the loop orbit, time intervals of the deviation timings being determined so that a mixture of product ions will not occur while the deviated ions are dissociated and mass analyzed; and d) an analysis step for sequentially deviating ions having each of the plurality of masses left on the loop orbit in accordance with the determined deviation timings, for dissociating the deviated ions by the dissociation means to generate product ions, and for analyzing the product ions by the mass analyzing means.