Abstract: An ion cell having an axis includes a sheath of individual electrodes that extends along the axis and defines an internal volume. Adjacent individual electrodes are electrically insulated from each other. The individual electrodes each receive a DC potential and RF voltage. At least some of the individual electrodes have a width that varies in the axial direction such that an electrical effect on an axis potential varies along the axis of the ion cell.

Abstract: In a linear ion trap ions of both positive and negative polarities are stored simultaneously for fragmentation reactions caused by electron transfer dissociation (ETD). The ion trap comprises a plurality of parallel pole rods or stacked rings and the ions are stored by applying two phases of a first RF voltage to the pole rods or stacked rings in alternation, thereby radially confining both positive and negative ions. A second, single-phase RF voltage is applied to all the pole rods or stacked rings in common and creates a pseudopotential barrier at the ends of the linear ion trap that acts axially on ions of both polarities in order to maintain the ions in the trap.

Abstract: The invention relates to RF voltage-operated ion guides based on stacked apertured diaphragms. The invention provides ion guides consisting of diaphragm stacks that permit the ion beam to be shaped in cross-section so that it corresponds to the acceptance profile of the subsequent section of the device, therefore yielding optimal ion transmission. For this purpose, at least some of the diaphragms in the diaphragm stacks do not have circular openings, but instead have openings which shape the cross section of the emerging ion beam in the desired manner. It is possible, for instance, to obtain elliptical beam cross sections, divided beams or beams focused to the shape of a fine thread at the output of the diaphragm stacks.

Abstract: The invention relates to time-of-flight mass spectrometers, equipped with ion reflector and ion detector, with orthogonal ion injection and outpulsing of a segment of the ion beam perpendicular to the direction of injection in a pulser. The invention is directed to a time-of-flight mass spectrometer in which a reflector and an ion detector each have an angular offset about an axis that is perpendicular to the respective directions of injection and deflection. This allows a large distance to be used between the pulser and detector with the highest possible utilization of ions.

Abstract: In a tandem mass spectrometer ions are created only once and stored in an ion reservoir. A particular ion species to be analyzed is then exported from the reservoir through a mass selective ion gate without damaging the other ion species remaining in the reservoir. All subsequent analyses are conducted on these stored ions, without adding further ions so that no changes in the concentrations of the stored ion species occur. The exported ions are fragmented, and a fragment ion mass spectrum is measured in a mass analyzer, preferably in a time-of-flight mass analyzer with orthogonal ion injection. The processes of exporting a selected ion species with subsequent fragmentation and the acquisition of the fragment ion spectrum can be repeated for any number of ion species stored in the reservoir.

Abstract: The invention relates to two-dimensional quadrupole systems along whose axis an axial DC field is superimposed. The invention involves coating the hyperbolic or cylindrical surfaces of quadrupole systems with thin insulating layers and metal films thereupon and generating axial potential gradients or saddle ramps using appropriate electrical supply of DC potentials and superimposed RF voltages to the metal films. Systems of this type can be used in a plurality of ways, ranging from mass filters with high transmission to fragmentation cells with extremely low ion losses.

Abstract: The invention relates to RF voltage-operated ion guides based on stacked apertured diaphragms. The invention provides ion guides consisting of diaphragm stacks that permit the ion beam to be shaped in cross-section so that it corresponds to the acceptance profile of the subsequent section of the device, therefore yielding optimal ion transmission. For this purpose, at least some of the diaphragms in the diaphragm stacks do not have circular openings, but instead have openings which shape the cross section of the emerging ion beam in the desired manner. It is possible, for instance, to obtain elliptical beam cross sections, divided beams or beams focused to the shape of a fine thread at the output of the diaphragm stacks.

Abstract: The invention relates to the construction and operation of a slit diaphragm pulser for a time-of-flight mass spectrometer with orthogonal injection of the ions to be examined. The invention includes switching three diaphragm potentials during a transition from a filling phase to an acceleration phase in order to maintain a potential along the axis of the injected ion beam at a constant level, to prevent any penetration by the accelerating fields during the filling phase and to obtain extremely high mass resolution in the acceleration phase through a lens effect.

Abstract: The invention relates to the construction and operation of a slit diaphragm pulser for a time-of-flight mass spectrometer with orthogonal injection of the ions to be examined. The invention includes switching three diaphragm potentials during a transition from a filling phase to an acceleration phase in order to maintain a potential along the axis of the injected ion beam at a constant level, to prevent any penetration by the accelerating fields during the filling phase and to obtain extremely high mass resolution in the acceleration phase through a lens effect.

Abstract: The invention relates to time-of-flight mass spectrometers, equipped with ion reflector and ion detector, with orthogonal ion injection and outpulsing of a segment of the ion beam perpendicular to the direction of injection in a pulser. The invention is directed to a time-of-flight mass spectrometer in which a reflector and an ion detector each have an angular offset about an axis that is perpendicular to the respective directions of injection and deflection. This allows a large distance to be used between the pulser and detector with the highest possible utilization of ions.