Curved ion guide with varying ion deflecting field and related methods
AssigneeAgilent Technologies, Inc.
InventorFelician Muntean
Life of this patent
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Abstract
An ion guide includes a plurality of curved electrodes and an ion deflecting device. The electrodes are arranged about and radially spaced from a central curved axis, and circumscribe a curved ion guide region from an ion entrance to an ion exit. The ion deflecting device may include a device for applying a DC electric field to one or more electrodes in a radial direction. The magnitude of the DC electric field, and thus the ion deflecting force, varies along the curved axis. The ion guide may for example operate as a collision cell or like instrument.
Claims20
An ion guide comprising:
- a plurality of curved electrodes arranged about a curved central axis, the curved central axis being co-extensive with an arc of a circular section having a radius of curvature, each electrode being radially spaced from the curved central axis, wherein the plurality of electrodes circumscribe a curved ion guide region arranged about the curved central axis, the ion guide region beginning at an ion entrance and ending at an ion exit;
- and
- an ion deflecting device configured for applying a radial DC electric field across the ion guide region at a magnitude that varies along the curved central axis, wherein the magnitude is at a maximum at the ion entrance and decreases along the curved central axis toward the ion exit.
A method for guiding an ion through an ion guide comprising:
- transmitting the ion into a curved ion guide region of the ion guide, the ion guide region being circumscribed by a plurality of curved electrodes arranged about a central curved axis, the curved central axis running through the ion guide region co-extensively with an arc of a circular section having a radius of curvature, each electrode being radially spaced from the curved central axis, wherein the curved ion guide region is arranged about the curved central axis, the ion guide region beginning at an ion entrance and ending at an ion exit;
- generating a RF electric field across the ion guide region to focus the ion to motions generally along the curved central axis;
- and
- generating a radial DC electric field across the ion guide region at a magnitude that varies along the central curved axis to provide an axially varying, radially directed ion deflecting force, wherein the magnitude is at a maximum at the ion entrance and decreases along the curved central axis toward the ion exit.
Dependencies are inferred from the claim text.