Patent ID: 10600631

Abstract:
An ion trap having a segmented electrode structure having a plurality of segments consecutively positioned along an axis, wherein each segment of the segmented electrode structure includes a plurality of electrodes arranged around the axis. A first voltage supply is configured to operate in a radially confining mode in which at least some electrodes belonging to each segment are supplied with at least one AC voltage waveform so as to provide a confining electric field for radially confining ions within the segment. A second voltage supply is configured to operate in a trapping mode in which at least some of the electrodes belonging to the segments are supplied with different DC voltages so as to provide a trapping electric field that has an axially varying profile for urging ions towards and trapping ions in a target segment of the plurality of segments. A first chamber is configured to receive ions from an ion source, wherein a first subset of the segments are located within the first chamber. A second chamber is configured to receive ions from the first chamber, wherein a second subset of the segments are located within the second chamber, and wherein the target segment is one of the second subset of segments. A gas pump is configured to pump gas out from the second chamber so as to provide the second chamber with a lower gas pressure than the first chamber. A gas flow restricting section is located between the first chamber and second chamber, wherein the gas flow restricting section is configured to allow ions to pass from the first chamber to the second chamber whilst restricting gas flow from the first chamber to the second chamber.