Abstract: A method of analyzing ions comprising generating ions from a sample in an ion source, delivering them into a vacuum region of a vacuum enclosure comprising an ion mobility analyser having an ion drift region formed between opposing electrodes defining an analytical gap. The ions emerge from the ion inlet as a supersonic jet of a buffer gas within which the ions are entrained to enter the drift region and, e.g., prior to mass spectral analysis of the ions in a downstream vacuum region, conducting differential ion mobility analysis of the ions in the first vacuum region. Prior to conducting differential ion mobility analysis (e.g.

Abstract: An apparatus for nulling a magnetic field within a nulling region in an external ambient magnetic field comprising a plurality of separate magnetic field generating elements 102 are located at separate respective locations surrounding the nulling region for generating respective nulling magnetic fields extending into the nulling region. A plurality of magnetic field sensing elements 103 are positioned at a plurality of respective separate locations within the nulling region for sensing respective values of the magnetic field within the nulling region.

Abstract: A device for performing field asymmetric waveform ion mobility spectrometry, “FAIMS”, including a power supply that applies voltage waveforms to first and second segmented planar electrodes to produce an asymmetric time dependent electric field in an analytical gap for FAIMS analysis of ions . The voltage waveforms are configured such that the asymmetric time dependent electric field has curved contours of equal field strength when viewed in a plane perpendicular to the analytical axis so as to focus ions having different differential mobilities towards different spatial domains, each spatial domain extending along a respective curved contour of equal field strength when viewed in a plane perpendicular to the analytical axis. A focus controller is configured to allow a user to change the curvature of the contours of equal field strength so as to change the strength of focussing provided by the asymmetric time dependent electric field.

Abstract: A device for performing field asymmetric waveform ion mobility spectrometry, “FAIMS” including first and second segmented planar electrodes, each electrode including three or more segments and extending in a direction parallel to an analytical axis of the device, the first and second segmented electrodes are separated from each other to provide an analytical gap therebetween; and propelling means for propelling ions through the analytical gap in a direction parallel to the analytical axis. The device is configured to operate in: a FAIMS mode in which a power supply applies voltage waveforms to the segments to produce an asymmetric time dependent electric field in the analytical gap for FAIMS analysis of ions propelled through the analytical gap; and a transparent mode in which the power supply applies voltage waveforms to the to produce a confining electric field in the analytical gap for focussing ions towards the longitudinal axis.

Abstract: A device for performing field asymmetric waveform ion mobility spectrometry, “FAIMS,” including first and second segmented planar electrodes, each electrode including three or more segments and extending in a direction parallel to an analytical axis of the device, wherein the first and second segmented electrodes are separated from each other to provide an analytical gap therebetween; and propelling means for propelling ions through the analytical gap in a direction parallel to the analytical axis. The device is configured to operate in a FAIMS mode in which a power supply applies voltage waveforms to the segments to produce an asymmetric time dependent electric field in the analytical gap for FAIMS analysis of ions propelled through the analytical gap. The asymmetric time dependent electric field has substantially straight contours of equal field strength in a plane perpendicular to the analytical axis to focus ions having different differential mobilities towards different spatial domains.

Abstract: A device for performing field asymmetric waveform ion mobility spectrometry, “FAIMS” including first and second segmented planar electrodes, each electrode including three or more segments and extending in a direction parallel to an analytical axis of the device, the first and second segmented electrodes are separated from each other to provide an analytical gap therebetween; and propelling means for propelling ions through the analytical gap in a direction parallel to the analytical axis. The device is configured to operate in: a FAIMS mode in which a power supply applies voltage waveforms to the segments to produce an asymmetric time dependent electric field in the analytical gap for FAIMS analysis of ions propelled through the analytical gap; and a transparent mode in which the power supply applies voltage waveforms to the to produce a confining electric field in the analytical gap for focussing ions towards the longitudinal axis.

Abstract: A device for performing field asymmetric waveform ion mobility spectrometry, “FAIMS,” including first and second segmented planar electrodes, each electrode including three or more segments and extending in a direction parallel to an analytical axis of the device, wherein the first and second segmented electrodes are separated from each other to provide an analytical gap therebetween; and propelling means for propelling ions through the analytical gap in a direction parallel to the analytical axis. The device is configured to operate in a FAIMS mode in which a power supply applies voltage waveforms to the segments to produce an asymmetric time dependent electric field in the analytical gap for FAIMS analysis of ions propelled through the analytical gap. The asymmetric time dependent electric field has substantially straight contours of equal field strength in a plane perpendicular to the analytical axis to focus ions having different differential mobilities towards different spatial domains.

Abstract: A device for performing field asymmetric waveform ion mobility spectrometry, “FAIMS”, including a power supply that applies voltage waveforms to first and second segmented planar electrodes to produce an asymmetric time dependent electric field in an analytical gap for FAIMS analysis of ions. The voltage waveforms are configured such that the asymmetric time dependent electric field has curved contours of equal field strength when viewed in a plane perpendicular to the analytical axis so as to focus ions having different differential mobilities towards different spatial domains, each spatial domain extending along a respective curved contour of equal field strength when viewed in a plane perpendicular to the analytical axis. A focus controller is configured to allow a user to change the curvature of the contours of equal field strength so as to change the strength of focussing provided by the asymmetric time dependent electric field.

Abstract: An electromagnet assembly suitable for mass spectrometer comprising one yoke; and two pole pieces; the pole pieces being comprised in a vacuum chamber and being separated from each other by a pole piece gap defining a passage for the charged particles to be deflected; the yoke forming a bridge over the two pole pieces thus defining a magnetic circuit. The electromagnet assembly further comprises one electrical circuit for generating a magnetic flux in the magnetic circuit, the electrical circuit being included in the yoke. The electromagnet assembly is remarkable in that the pole pieces are electrically insulated from the electrical circuit and from the yoke by first electrical insulating means and are electrically insulated from the vacuum chamber.

Abstract: An electromagnet assembly suitable for mass spectrometer comprising one yoke; and two pole pieces; the pole pieces being comprised in a vacuum chamber and being separated from each other by a pole piece gap defining a passage for the charged particles to be deflected; the yoke forming a bridge over the two pole pieces thus defining a magnetic circuit. The electromagnet assembly further comprises one electrical circuit for generating a magnetic flux in the magnetic circuit, the electrical circuit being included in the yoke. The electromagnet assembly is remarkable in that the pole pieces are electrically insulated from the electrical circuit and from the yoke by first electrical insulating means and are electrically insulated from the vacuum chamber.