An ion guide (40) is disclosed that comprises an ion confinement region having a first cross-sectional profile with a first cross-sectional area A1 in a plane orthogonal to a direction of ion transmission. An attenuation device ejects or deflects ions having spatial positions which fall outside of a second cross-sectional profile having a second cross-sectional area A2, wherein A2<A1.

A mass spectrometry method comprises: receiving a stream of ions at an inlet end of an ion transport device; accumulating a first portion of the ion stream at a first electrical potential well at a first position within the ion transport device between the inlet and outlet ends; creating a generally descending potential profile within the ion transport apparatus between a second position and the outlet end and, simultaneously, creating a second potential well at a third position within the ion transport apparatus, the second position disposed between the first position and the inlet end, the third position disposed between the second position and the inlet end; and transporting the accumulated first portion of the ion stream from the first position to the outlet end under the impetus of the generally descending potential profile and, simultaneously, accumulating a second portion of the ion stream at the second potential well.

An ion guide device includes a plurality of ring electrodes disposed in parallel, wherein each ring electrode includes at least 4 electrode units separated from each other, a channel for ion transmission is formed inside the plurality of ring electrodes, and an arrangement direction of the plurality of ring electrodes defines an axial direction of ion transmission; an radio-frequency voltage source, for applying out-of-phase radio-frequency voltages on the neighboring electrode units belonging to the same ring electrode, and applying in-phase radio frequency voltages on a neighboring electrode units along the axial direction, thereby forming an radio-frequency multipole field that confine ions in the ion guide device; and a direct-current voltage source, wherein the ions are transmitted off-axis and focused to a position closer to an inner surface of the ring electrode under a combined action of the radio-frequency voltage and the direct-current voltage.

An ELIT includes voltage sources (1101), switches (1102), a first set of electrode plates (1110) aligned along a central axis, and a second set of electrode plates (1120) aligned along the central axis with the first set. A first group of plates (310, 320; 810, 820) of the first set and the second set is positioned to trap ions within a first path length (340, 940). A second group of plates (410, 420) of the first set and the second set is positioned to trap ions within a shorter second path length (440, 1040). The switches select the first path length by applying voltages from the voltage sources to the first set and the second set that cause the first group of plates to trap ions within the first path length. Alternatively, the switches can select the second path length by applying voltages that cause the second group of plates to trap ions within the second path length.

A system for separating ions includes first and second surfaces extending along first and second perpendicular directions, an ion channel defined between the surfaces and configured to receive a stream of ions, first and second electrode arrays each including a plurality of electrodes extending in a third direction and respectively associated with the first and second surfaces, means for causing gas to flow across the ion channel in a fourth direction substantially opposite the first direction, and a controller configured to apply a DC voltage gradient to the electrode arrays. The electrode arrays are configured to generate an electric field based on the DC voltage gradient. The electric field and the flow of gas are configured to direct ions having mobilities in a first mobility range along a first path and ions having mobilities in a second mobility range along a second path.

An ion trap apparatus is provided. The ion trap apparatus comprises two or more radio frequency (RF) rails formed with substantially parallel longitudinal axes and with substantially coplanar upper surfaces; and two or more sequences of trapping and/or transport (TT) electrodes with each sequence formed to extend substantially parallel to the substantially parallel longitudinal axes of the RF rails. The two or more RF rails and the two or more sequences of TT electrodes define an ion trap. The two or more sequences of TT electrodes are arranged into a number of zones. Each zone comprises wide matched groups of TT electrodes and at least one narrow matched group of TT electrodes. A wide TT electrode is longer and/or wider in a direction substantially parallel to the substantially parallel longitudinal axes of the RF rails than a narrow TT electrode.

There is provided a method of guiding ions, comprising providing an ion guide comprising a plurality of electrodes, confining ions radially within said ion guide by applying one or more voltages to said plurality of electrodes, applying an orthogonal DC field along at least a portion of said ion guide in order to control the temperature of ions as they travel through said ion guide, and applying an electrostatic driving potential to said plurality of electrodes to urge ions along the axial length of the ion guide, wherein said electrostatic driving potential is applied in the form of a DC travelling wave potential or other transient DC potential.

A miniature electrode apparatus is disclosed for trapping charged particles, the apparatus includes, along a longitudinal direction, a first end cap electrode, a central electrode having an aperture, and a second end cap electrode. The aperture is elongated in the lateral plane and extends through the central electrode along the longitudinal direction and the central electrode surrounds the aperture in a lateral plane perpendicular to the longitudinal direction to define a transverse cavity for trapping charged particles. Electric fields can be applied in a y-direction of the lateral plane across one or more planes perpendicular to the longitudinal axis to translocate and/or manipulate ion trajectories.

An ion guide electrode assembly (10) for an ion-mobility spectrometer is described. The electrode assembly (10) comprises a first sheet (100), having first and second surfaces (110, 120) comprising a plurality of corresponding regions (111, 112, 121, 122). The first sheet (100) comprises a set of N electrodes (130, 140), including a first electrode (130) and a second electrode (140), provided as tracks mutually spaced apart on the first surface (110) thereof. The electrode assembly (10) is arrangeable in a planar configuration and preferably in a tubular configuration. In the tubular configuration, a first part (131) of the first electrode (130), provided in a first region 111 of the first surface (110), overlays a second region (122) of the second surface (120). In the tubular configuration, the first part (131) of the first electrode (130) overlaps a second part (132) of the first electrode (130) and/or a second part (142) of the second electrode (140), provided in a second region (112) of the first surface (110).

The invention relates to an ion transport device which is designed to transport ions by means of an electric field. The ion transport device has an ion transport channel in which an ion transport chamber is formed. In order to generate the electric field, the ion transport device has a plurality of field generating electrodes which are arranged one behind the other along the length of the ion transport channel in order to move ions through the ion transport chamber in a transport direction. The invention additionally relates to an ion mobility spectrometer and to a mass spectrometer.