Patent ID: 9177776
Filing Date: 2015-11-03
Classification: H01J

Abstract:
1. An ion guide comprising: a plurality of electrodes; a first device arranged and adapted to apply a first RF voltage to at least some of said electrodes; and a second device arranged and adapted to apply one or more DC voltages to one or more electrodes in order to maintain one or more axial DC voltage barriers at one or more positions along the ion guide so as to confine at least some ions axially within said ion guide; wherein said ion guide further comprises: a third device arranged and adapted to apply a second RF voltage to at least some of said electrodes, wherein two or more axially adjacent electrodes are maintained at a same first RF phase of said second RF voltage and two or more subsequent axially adjacent electrodes are maintained at a same second RF phase of said second RF voltage, said first RF phase of said second RF voltage being different from or opposite to said second RF phase of said second RF voltage; and a fourth device arranged and adapted to progressively increase, linearly increase, or increase in a stepped or other manner an amplitude, height or depth or frequency of either said first RF voltage or said second RF voltage such that at least some of said ions overcome said one or more axial DC voltage barriers and emerge axially from said ion guide.