Patent ID: 7999223
Filing Date: 2011-08-16
Classification: H01J

Abstract:
1. A multi-reflection or closed orbit ion trap assembly, comprising: an ion trap; an electrode arrangement including an ion gate, the ion gate being switchable between a first gating state wherein ions, when following a path within the ion trap, are directed along a first ion path, and a second gating state wherein ions, when following a path within the ion trap, are directed along a second ion path; and a system controller arranged to permit identification, from within a plurality of species of charged particles introduced into, or formed within the ion trap, a plurality n(≧2) of ion species of interest each of which n identified ion species undergoes substantially isochronous oscillations or orbits along the path within the ion trap, the oscillations or orbits having period characteristic of the respective mass to charge ratio m/z whereby the ions of those species identified to be of interest are separated from those ions not so identified.