| 摘要 |
A mass spectrometer is disclosed comprising a time of flight mass analyser 7. The time of flight mass analyser 7 comprises a ring stack ion guide comprising a plurality of apertured electrodes 1 which are interconnected by a series of resistors 2 forming a potential divider. Ions are confined radially within the ion guide by the application of a two-phase RF voltage 6 to the electrodes 1. A single phase additional time-varying inhomogeneous RF voltage is applied across the potential divider so that an inhomogeneous pseudo-potential force is maintained along the length of the ion guide. |
