Mass spectrometer

摘要

A mass analyzer is provided comprising a plurality of electrodes having apertures through which ions are transmitted. A plurality of pseudo-potential corrugations are created along the axis of the mass analyzer. The amplitude or depth of the pseudo-potential corrugations is inversely proportional to the mass to charge ratio of an ion. Transient DC voltages are applied to the electrodes in order to urge ions along the length of the mass analyzer. The amplitude of the transient DC voltages applied to the electrodes is increased with time and ions are caused to be emitted from the mass analyzer in reverse order of their mass to charge ratio. Two AC or RF voltages are applied to the electrodes. The first AC or RF voltage is arranged to provide optimal pseudo-potential corrugations while the second AC or RF voltage is arranged to provide optimal radial confinement of ions within the mass analyzer.

主权项

1. A mass analyzer comprising:
an ion guide including a plurality of electrodes; a first voltage source for creating one or more axial time averaged or pseudo-potential barriers, corrugations or wells created along at least a portion of an axial length of said ion guide; and a second voltage source forming an electric field, voltage, or waveform along at least a portion of the guide so that in a mode of operation ions having mass to charge ratios within a first range exit said ion guide axially while ions having mass to charge ratios within a second range are axially confined within said ion guide.