Patent ID: 7550717

Claim:
An apparatus for transmitting ions in the gas phase, the apparatus selectably switchable between a first operating mode for transmitting ions with separation according to the FAIMS principle and a second operating mode for transmitting ions using the principle of an rf-only ion guide device, the apparatus comprising: an analyzer assembly comprising an analytical gap defined by a space that is bounded by at least four flat-plate electrodes, the at least four flat-plate electrodes arranged around a longitudinal axis that extends along a first direction through the analytical gap, the at least four flat-plate electrodes comprising: a first flat-plate electrode and a second flat-plate electrode, the second flat-plate electrode facing the first flat-plate electrode and spaced-apart therefrom along a second direction that is normal to the first direction; and, a third flat-plate electrode and a fourth flat-plate electrode, the fourth flat-plate electrode facing the third flat-plate electrode and spaced-apart therefrom along a third direction that is substantially normal to both the first direction and the second direction; a plurality of lateral segment electrodes, including a first lateral segment electrode and a second lateral segment electrode disposed one each laterally adjacent opposite edges of the first flat-plate electrode and extending along the first direction, and a third lateral segment electrode and a fourth lateral segment electrode disposed one each laterally adjacent opposite edges of the second flat-plate electrode and extending along the first direction; and, at least an electrical controller in communication with the analyzer assembly for establishing a first electric field within the analytical gap for separating ions according to the FAIMS principle when operating in the first operating mode and for establishing a second electrical field within the analytical gap for transmitting ions using the principle of an rf-only ion guide device when operating in the second operating mode, the electrical controller being further configured to apply DC potentials to the plurality of lateral segment electrodes to generate a DC field that laterally focuses ions to the longitudinal axis.