Ion Beam Focusing

Abstract

An ion focusing device comprising an ion collection element comprising a plurality of N curved electrodes extending around an axis of the ion collection element and an aperture on an axis of the ion collection element. A multipole ion guide adjacent the ion collection element and having a plurality of N elongate electrodes extending parallel to and around an axis of the multipole ion guide, wherein the axis of the multipole ion guide coincides with the axis of the ion collection element, wherein each of the N curved electrodes of the ion collection element are configured to receive a radio frequency, RF, signal having the same phase as an RF signal configured to be applied to at least one elongate electrode of the plurality of elongate electrodes of the multipole ion guide, and further wherein at least two of the N electrodes of the ion collection element are configured to receive RF signals of a different phase.

Dependencies are inferred from the claim text.