| 摘要 |
A mass analyser is disclosed comprising an annular ion guide having a longitudinal axis, said ion guide being formed from axially segmented inner and outer cylindrical electrode arrangements. Ions are introduced into a first annular ion guide section so that the ions form substantially stable circular orbits therein about the longitudinal axis, before they are orthogonally accelerated from the first annular ion guide section into the second annular ion guide section. One or more parabolic DC potentials are maintained along a portion of the second annular ion guide section so that ions undergo simple harmonic motion therein, an inductive ion detector being arranged at an isochronous plane within the second annular ion guide section so as to detect ions as they oscillate within the device. |
