Ion detection

摘要

A mass analyzer in which ions form packets that oscillate with a period has an ion detector comprising: a detection arrangement; and compensation circuitry. The detection arrangement may comprise: a plurality of detection electrodes detecting image current signals from ions in the mass analyzer; and a preamplifier, providing an output based on the image current signals. The compensation circuitry provides a compensation signal to a respective compensatory part of the detection arrangement, based on one or more of the image current signals. A capacitance between each of the compensatory parts of the detection arrangement and a signal-carrying part of the detection arrangement affects the signal-to-noise ratio of the preamplifier output. A generator may provide a trapping field defining an ion trapping volume and a shielding conductor may be positioned between two detection electrodes, with a controller applying a voltage to the shielding conductor based on a detected image current.

主权项

1. An electrostatic ion trapping device comprising:
a trapping field generator, configured to provide a trapping field defining an ion trapping volume, in which ions are confined; a detection arrangement, configured to detect an image current from ions trapped in the ion trapping volume, using a plurality of detection electrodes; a shielding conductor, positioned between a first detection electrode and a second detection electrode from the plurality of detection electrodes; and a controller, configured to apply a voltage to the shielding conductor based on an image current detected by at least one of the plurality of detection electrodes.