Focusing mass spectrometer ion guide, spectrometer and methods

摘要

Ion guide includes a plurality of stages. Electric field in each stage leads to the ions along the guide shaft. Within each stage, amplitude and frequency and decomposition potential of the electric field may vary independently. The geometry of the rod, the electric field of similar shape from stage to stage is maintained, which allows efficient induction of ions along the axis. In particular, each rod segment of the i-th stage, cross-sectional radius r _i and, having a central axis located a distance R _i + r _i from the guide shaft. The ratio _r i / R i is substantially constant along the guide shaft, whereby the shape of the electric field is maintained.