LINEAR ION TRAP AND METHOD OF CONTROLLING MOVEMENT OF IONS USING ASYMMETRICAL CONFINEMENT FIELD Russian patent published in 2009 - IPC H01J49/42 

FIELD: physics.

SUBSTANCE: linear ion trap has four electrodes and uses an asymmetrical confinement field, the centre of which is displaced from the geometric centre of the trap. The asymmetrical confinement field can include main alternating potential, which provides for the quadrupole component, and an additional alternating potential. The main alternating potential is applied across oppositely lying pairs of electrodes, and the additional alternating potential is applied across one electrode pair. The additional alternating potential can carry a dipole component to give the confinement field an asymmetric property. The additional alternating potential can also carry a hexapole component, used for generating non-linear resonance. Auxiliary alternating potential can also be applied across the same electrode pair, where the auxiliary alternating potential is used as additional alternating potential which amplifies resonance activation. The working point for ion extraction can be chosen such that, there is possibility of using a pure (independent) resonance condition to increase amplitude of oscillation of the ion preferably in one direction. Ions trapped by the combined field can be extracted with mass selection in a single direction through an opening in one of the electrodes.

EFFECT: stability and reliability of the system.

20 cl, 26 dwg