Patent ID: 9318310
Filing Date: 2016-04-19
CPC Classification: H01J

Claim Text:
1. A method for operating a mass spectrometer for a plurality of selected mass-to-charge ranges, the mass spectrometer having an ion trap, the plurality of selected mass-to-charge ranges constituting an overall mass-to-charge range, for each of the plurality of selected mass-to-charge ranges the method comprising: filling the ion trap with fragmented ions of the selected mass-to-charge ranges; cooling the fragmented ions trapped in the ion trap for a first cooling period; applying an RF voltage and a resolving direct current voltage to the ion trap for eliminating any remaining fragmented ions outside the selected ion mass-to-charge range and retaining ions within the selected ion mass-to-charge range; cooling the retained ions in the ion trap for a second cooling period; and scanning the retained ions out of the ion trap and detecting the ions released therefrom.