Abstract: An ion mobility spectrometer is described having an ion filter in the form of multiple parallel ion channels defined by conductive layers separated by non-conductive layers. A time-varying electric potential applied to the conductive layers allows the filter to selectively admit ion species. The device may be used without a drift gas flow. Microfabrication techniques are described for producing microscale spectrometers, as are various uses of the spectrometer.

Abstract: An ion trap mass analyzer includes an elongated tunnel that has a wall, a longitudinal axis and an inner space. The wall includes a substrate and conductor trace patterns. There is also a variable electric potential means for providing electric potentials which is connected to the conductor trace patterns. The conductor trace patterns and the variable electric potential means provide a variable electric field within the inner space of the tunnel for transferring, storing, and analyzing ions.

Abstract: The present invention provides a radio frequency (RF) power supply in a mass spectrometer. The power supply provides an RF signal to electrodes of a storage device to create a trapping field. Such ion storage devices are often used to store ions prior to ejection to a subsequent mass analyzer. The RF field is usually collapsed prior to ion ejection. The present invention provides a RF power supply comprising: a RF signal supply, a coil arranged to receive the signal provided by the RF signal supply and to provide an output RF signal for supply to electrodes of an ion storage device, and a shunt including a switch operative to switch between a first open position and a second closed position in which the shunt including a switch operative to switch between a first open position and a second closed position in which the shunt shorts the coil output.

Abstract: There is provided a linear ion trap having an ion guide and a method of operating same. The ion guide has a first end and a second end. The method involves a) providing a first group of ions within the ion guide; b) providing a second group of ions within the ion guide, the second group of ions being opposite in polarity to the first group of ions; c) providing an RF drive voltage to the ion guide to radially confine the first group of ions and the second group of ions in the ion guide; d) providing a gas flow of an inert gas in a first axial direction away from the first end of the ion guide and toward a middle of the ion guide to repel both the first group of ions and the second group of ions from the first end of the ion guide; and, e) providing a trapping region barrier for repelling both the first group of ions and the second group of ions away from the second end of the ion guide.

Abstract: The invention provides an apparatus for producing an image of a global surface of an ion source sample plate that is exterior to an ion source. In general terms, the apparatus contains a sample plate for an ion source, an imaging device (e.g., a CCD or CMOS camera) and an illumination device that is configured to produce a light beam that contacts the sample plate surface to define a grazing angle between the light beam and the sample plate surface. The apparatus may be present at a location that is remote to the ion source.

Abstract: In a three-dimensional Paul RF ion trap at least one of the ring electrode and end cap electrodes is structured to produce a high capture efficiency for analyte ions introduced into the trap. The electrode structuring may be produced by an electrode surface profile having edges or protrusions, resulting in a scattering reflection of the introduced ions. Alternatively, at least one electrode may be formed by physically separate electrode components. In one embodiment, the trap can be switched between operating as a linear ion trap with good capture efficiency and operating as a three-dimensional ion trap with good ion reaction conditions.

Abstract: A method of generating a mass spectrum from an FTMS is disclosed. A first quantity of ions from a source, having a first m/z range, is captured and detected in the FTMS measurement cell to produce a first output. A second quantity of ions, having a second m/z range which at least partially does not overlap with the first m/z range, is then captured and detected so as to produce a second output. The two outputs are then combined using a processor so as to “stitch” together the outputs, which may be FTMS transients or may first be Fourier Transformed into the frequency mass domain, into a composite output from which a composite mass spectrum covering the full range of m/z ratios included by the first and second ranges can be produced.

Abstract: Systems and methods for optimizing the analysis of co-eluting compounds during a cycle of a tandem mass spectrometer system are provided. The tandem mass spectrometer system switches fast from analyzing one compound ion to analyzing another compound ion and from one collision cell energy to another. The fast switching allows complex sampling patterns that improve coverage of the ionic signal of the co-eluting compounds while allowing different collision cell energies to be analyzed.

Abstract: A detector system for detecting trace molecules. The detector includes an ion trap that is coupled to an ionizer and a detector. The system also includes a controller that can generate voltage potentials within the ion trap. The controller can generate a voltage waveform to isolate one or more ions within the ion trap. The controller can then generate a voltage to dissociate the isolated ion(s). The controller can vary the dissociating voltage to dissociate and detect different ions. For example, the controller may vary the amplitude of the voltage to dissociate a target ion. Other techniques are described which generally improve the speed of detecting different target ions.

Abstract: A FAIMS cell has an elongated inner electrode with a longitudinal axis extending along a first direction. The inner electrode has a curved outer surface that defines a circle when viewed in a cross section that is taken in a plane normal to the longitudinal axis, which itself passes through the center of the circle so defined. An outer electrode having an inner surface is disposed in a spaced-apart facing relationship relative to the outer surface of the inner electrode so as to define an analytical gap therebetween. A first ion inlet orifice is defined through a first portion of the outer electrode, and an ion outlet orifice is defined through a second portion of the outer electrode. In particular, the first ion inlet orifice has a first ion injection axis that does not pass through the center of the circle. Furthermore, the second electrode does not have defined through any portion thereof an ion inlet orifice having an ion injection axis that passes through the center of the circle.

Abstract: Systems and methods of the invention include a branched radio frequency multipole configured to act, for example, as an ion guide. The branched radio frequency multipole comprises multiple ion channels through which ions can be alternatively directed. The branched radio frequency multipole is configured to control which of the multiple ion channels ions are directed, through the application of appropriate potentials.

Abstract: A FAIMS cell including one of side-to-side cylindrical geometry electrodes and stacked-plate electrodes is adapted with a medial surface feature for focusing ions along a lateral direction within an ion separation region of the FAIMS cell. The medial surface feature is provided as one of a recessed channel within an electrode surface and a protruding ridge extending from an electrode surface. The medial surface feature is aligned with a defined aggregate direction of ion travel within the ion separation region for focusing ions along the lateral direction in opposition to the tendency of ions to spread out as a result of space charge repulsion, ion-ion repulsive forces, diffusion and gas flows. The electrical field and fluid dynamic effects produced by the medial surface feature beneficially affect ion transmission efficiency through the FAIMS cell.

Abstract: A switchable branched ion guide is disclosed. The switchable branched ion guide includes a trunk section, first and second branch sections, a junction connecting the trunk section to the branch sections, and a movable valve member located at the junction. The valve member may be moved between a first position in which ion travel is permitted between the trunk section and first branch section and is inhibited between the trunk section and the second branch section, and a second position in which ion travel is permitted between the trunk section and the second branch section and is inhibited between the trunk section and the first branch section. The branched ion guide may be utilized, for example, to controllably switch an ion stream between two destinations such as mass analyzers.

Abstract: A method and apparatus are provided for operating a linear ion trap. A linear ion trap configuration is provided that allows for increased versatility in functions compared to a conventional three-sectioned linear ion trap. In operation, the linear ion trap provides multiple segments, the segments spatially portioning an initial population of ions into at least a first and a second ion population. Each segment is effectively independent and ions corresponding to the first ion population are able to be manipulated independently from ions corresponding to ions corresponding to the second ion population; the ions having been generated by an ion source under the same conditions. The ions can then be expelled from the ion trap.

Abstract: A method and apparatus are provided for operating a linear ion trap. A linear ion trap configuration is provided that allows for increased versatility in functions compared to a conventional three-sectioned linear ion trap. In operation, the linear ion trap provides multiple segments, the segments spatially partitioning an initial ion population into at least a first and a second ion population, and enabling the ions corresponding to the first ion population to be expelled from the linear ion trap substantially simultaneously with the ions corresponding to the second ion population. Each segment is effectively independent and ions corresponding to the first ion population are able to be manipulated independently from ions corresponding to ions corresponding to the second ion population; the ions having been generated by an ion source under the same conditions.

Abstract: The invention relates to the acquisition of mass spectra of complex protein mixtures, often called protein profiles, for example to search for biomarkers which indicate stress situations, or to identify microbes. Up to now protein profiles have been acquired using ionization by matrix-assisted laser desorption with high detection sensitivity in linear time-of-flight mass spectrometers, but these display very poor mass resolution and a very poor reproducibility of the mass values. The invention provides methods which produce surprisingly similar mass spectra, but with far higher mass resolution and mass accuracy. Ionization takes place outside the vacuum at ambient pressure, preferably by means of laser desorption and CI post-ionization. Analysis of the ions takes place in a high-resolution mass spectrometer, for example a reflector time-of-flight mass spectrometer with orthogonal ion injection.

Abstract: A Q-pole type mass spectrometer can be used under a high-pressure atmosphere of more than 0.1 Pa. The Q-pole type mass spectrometer can analyze the mass of gas molecules continuously, and can separate mass properly even if an ion is injected at high speed in order to reduce the influence of an end electric field near an end face (fringing) of the Q-pole. The motion of the ions to be measured in the diameter direction is independent of the motion of ions in the axial direction within the Q-pole region of the Q-pole type mass spectrometer. In the Q-pole type mass spectrometer installed in a reduced pressure atmosphere, the motion of ions to be measured in the axial direction advancing from an ion source toward a collector, is controlled within the Q-pole region so as to separate the mass of the ions to be measured by Coulomb force generated by a quadrupole high-frequency electric field in the diameter direction.

Abstract: The mobility of mass-selected ions in gases is measured at pressures of a few hectopascal by selecting the ions under investigation in a quadrupole filter according to their mass-to-charge ratio m/z, measuring their mobility in a drift region at a pressure of a few hundred Pascal under the influence of a DC electric field and then filtering the measured ions by means of a quadrupole field in order to eliminate, or detect changes in, the mass-to-charge ratio. Several embodiments for the drift region are disclosed, in which the ions are kept in the axis of the drift region by RF fields. As these drift regions can also be utilized for a collision-induced decomposition of the ions, the device can additionally be used as a so-called triple quadrupole mass spectrometer.

Abstract: In this invention the technology is provided for rod shaped conductor member fabrication in situ, in position, in the mass filter spatial configuration by growth through vertically repeated conduit mold formations, filling the conduit increments with to be rod material, and coalescing the growth increments as the rod length is achieved.

Abstract: The invention provides a mass spectrometry system ion source containing a sample plate and an illumination device that is configured to produce a light beam that contacts the sample plate surface to define a grazing angle between the light beam and the sample plate surface. The ion source may also contain an imaging device, e.g., a CCD or CMOS camera or the like, for viewing the area. In one embodiment, the imaging device may be connected to a display, e.g., a video monitor. Methods and mass spectrometry systems empliying the ion source are also provided.

Abstract: A micromechanical field asymmetric ion mobility filter for a detection system includes a pair of spaced substrates defining between them a flow path between a sample inlet and an outlet; an ion filter disposed in the path and including a pair of spaced filter electrodes, one electrode associated with each substrate; and an electrical controller for applying a bias voltage and an asymmetric periodic voltage across the ion filter electrodes for controlling the paths of ions through the filter.

Abstract: A medical synchrotron which cycles rapidly in order to accelerate particles for delivery in a beam therapy system. The synchrotron generally includes a radiofrequency (RF) cavity for accelerating the particles as a beam and a plurality of combined function magnets arranged in a ring. Each of the combined function magnets performs two functions. The first function of the combined function magnet is to bend the particle beam along an orbital path around the ring. The second function of the combined function magnet is to focus or defocus the particle beam as it travels around the path. The radiofrequency (RF) cavity is a ferrite loaded cavity adapted for high speed frequency swings for rapid cycling acceleration of the particles.

Abstract: A SIFT or SIFDT apparatus in which the upstream quadrupole and the downstream quadrupole are housed within a single evacuated chamber with the upstream quadrupole being connected to the downstream quadrupole by a curved flow tube. In a preferred form the interior of the chamber is divided into sections by an electrostatic shield which shields the upstream quadrupole and source connection from the downstream quadrupole and detector.

Abstract: A mass spectrometer 10 comprises an ion source 12 which generates nebulized ions which enter an ion cooler 20 via an ion source block 16. Ions within a window of m/z of interest are extracted via a quadrupole mass filter 24 and passed to a linear trap 30. Ions are trapped in a potential well in the linear trap 30 and are bunched at the bottom of the potential well adjacent an exit segment 50. Ions are gated out of the linear trap 30 into an electrostatic ion trap 130 and are detected by a secondary electron multiplier 10. By bunching the ions in the linear trap 30 prior to ejection, and by focussing the ions in time of flight (TOF) upon the entrance of the electrostatic trap 130, the ions arrive at the electrostatic trap 130 as a convolution of short, energetic packets of similar m/z. Such packets are particularly suited to an electrostatic trap because the FWHM of each packet's TOF distribution is less than the period of oscillation of those ions in the electrostatic trap.

Abstract: A synchrocyclotron comprises a resonant circuit that includes electrodes having a gap therebetween across the magnetic field. An oscillating voltage input, having a variable amplitude and frequency determined by a programmable digital waveform generator generates an oscillating electric field across the gap. The synchrocyclotron can include a variable capacitor in circuit with the electrodes to vary the resonant frequency. The synchrocyclotron can further include an injection electrode and an extraction electrode having voltages controlled by the programmable digital waveform generator. The synchrocyclotron can further include a beam monitor. The synchrocyclotron can detect resonant conditions in the resonant circuit by measuring the voltage and or current in the resonant circuit, driven by the input voltage, and adjust the capacitance of the variable capacitor or the frequency of the input voltage to maintain the resonant conditions.

Abstract: In a method for exciting a precursor ion in an ion trap, the ion is trapped in a nonlinear trapping field that includes a quadrupolar field and a multipole field. The quadrupolar field is generated by applying a radio-frequency (RF) trapping voltage to the ion trap at a trapping amplitude and trapping frequency. A supplemental alternating-current (AC) voltage is applied to the ion trap at a supplemental amplitude and supplemental frequency. The supplemental amplitude is low enough to prevent ejection of the ion from the ion trap, and the supplemental frequency differs from the secular frequency of the ion by an offset amount. One or more operating parameters of the ion trap are adjusted, such that the ion absorbs energy from the supplemental field sufficient to undergo collision-induced dissociation (CID) without being in resonance with the supplemental field.

Abstract: Systems and methods of the invention include a branched radio frequency multipole configured to act, for example, as an ion guide. The branched radio frequency multipole comprises multiple ion channels through which ions can be alternatively directed. The branched radio frequency multipole is configured to control which of the multiple ion channels ions are directed, through the application of appropriate potentials. Thus, ions can alternatively be directed down different ion channels without the use of a mechanical valve.

Abstract: A micrometer-scale ion trap, fabricated on a monolithic chip using semiconductor micro-electromechanical systems (MEMS) technology. A single 111Cd+ ion is confined, laser cooled, and the heating measured in an integrated radiofrequency trap etched from a doped gallium arsenide (GaAs) heterostructure. Single 111Cd+ qubit ions are confined in a radiofrequency linear ion trap on a semiconductor chip by applying a combination of static and oscillating electric potentials to integrated electrodes. The electrodes are lithographically patterned from a monolithic semiconductor substrate, eliminating the need for manual assembly and alignment of individual electrodes. The scaling of this structure to hundreds or thousands of electrodes is possible with existing semiconductor fabrication technology.

Abstract: An atmospheric pressure ionization mass spectrometry system has an atmospheric pressure ionization chamber for ionizing a sample, an evacuated intermediate evacuation chamber into which generated ions are introduced through a capillary tube, and a vacuum chamber further downstream therefrom into which ions are introduced for mass separation. A partition wall separating the atmospheric pressure ionization chamber from the intermediate evacuation chamber includes a small orifice having a diameter corresponding to an internal channel diameter of the capillary tube. The capillary tube is detachably installed on the partition wall so that an outlet end of the capillary tube abuts on the small orifice. The internal channel of the capillary tube is in communication with the small orifice. The capillary tube can be installed and removed from the system without breaching the vacuum.

Abstract: An ion detection device, method and computer readable medium storing instructions for applying voltages to shutter elements of the detection device to compress ions in a volume defined by the shutter elements and to output the compressed ions to a collector. The ion detection device has a chamber having an inlet and receives ions through the inlet, a shutter provided in the chamber opposite the inlet and configured to allow or prevent the ions to pass the shutter, the shutter having first and second shutter elements, a collector provided in the chamber opposite the shutter and configured to collect ions passed through the shutter, and a processing unit electrically connected to the first and second shutter elements.

Abstract: Methods for applying an RF field in a two-dimensional electrode structure include applying RF voltages to one or more main electrodes and compensation electrodes. The voltages on the one or more compensation electrodes may be adjusted to be proportional to the voltages on the main electrodes. The adjustment(s) may be done to optimize the RF field for different modes of operation such as ion ejection and ion dissociation. For dissociation and other procedures involving ion excitation, the voltages applied to the one or more compensation electrodes may be different from the voltages applied to the one or more main electrodes. Electrode structures may include main trapping electrodes, one or more compensation electrodes, one or more ion exit apertures, and a device or circuitry for applying the various desired voltages.

Abstract: Methods for applying an RF field in a two-dimensional electrode structure include applying RF voltages to main electrodes and to compensation electrodes. The voltages on the compensation electrodes may be proportional to the voltages on the main electrodes so as to optimize the RF field for processes involving ion excitation, including collision-induced dissociation. Electrode structures may include main trapping electrodes, one or more compensation electrodes, one or more ion exit apertures, and a device or circuitry for applying the various desired voltages.

Abstract: A time of flight mass spectrometer according to the present invention includes: a) an ion source at which an ion starts flying; b) an energizer for giving a predetermined amount of energy to the ion to let the ion start flying from the ion source; c) an ion guide for forming a time-focusing flight path on which the ion flies once or repeatedly; d) a detector for detecting the ion after flying the flight path; e) an analysis controller for giving different amounts of energy to ions of the same kind using the energizer, and for measuring the values of the flight time of the ions from the ion source to the detector for the amount of energy; and f) a mass calculator for calculating or estimating the mass to charge ratio of the ion based on the difference in the values of the flight time of the ions.

Abstract: The invention provides, in various embodiments, systems and methods relating to enhancing the filtering and detection capability of ion mobility based systems by various techniques to counteract a charge buildup in the ion mobility based system.

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 provides an interface assembly for delivering an ionized analyte from an ionization apparatus into an ion mobility spectrometer. This allows analysis of biological and non-biological samples, even non-volatile solids, via differential mobility spectrometry, without fragmentation of molecules. The invention also provides portable sample analysis systems that operate at ambient pressure. Systems of the invention may be used for high molecular weight species detection, for example, drinking water contaminants, pathogenic biological agents, bio-organic substances, non-biological material, peptides, proteins, oligonucleotides, polymers, bacteria, and hydrocarbons.

Abstract: A method and apparatus for multiplexed data acquisition for gas-phase ion mobility coupled with mass spectrometry is described. Ion packets are injected into an ion mobility drift chamber at a rate faster than the ion mobility separation arrival time distribution. The convoluted arrival time distributions thus generated are deconvoluted by a mass spectrometer and post-processing algorithms.

Abstract: An improved rotating electric field ion mass spectrometer (REFIMS) provides for a smooth transition of the input ion beam from zero rotation to the desired level of field rotation. The REFIMS grid shape is changed from a fixed-diameter tunnel to that of a horn. The horn shape has a flare end with a larger entrance width that reduces the grid electric field strength to near zero and causes no abrupt deflection of the beam at the entrance, and tapers along the longitudinal z axis to a narrower width so that the field strength applied to the beam increases gradually until the correct field strength is obtained at its exit end for the desired rotation of the beam. Preferably, the horn shape in cross-section is hyperbolic, and the increase in field strength is approximately linear with distance along the z axis. The horn shaped device can provide a 2D spectral readout in which the ions are imaged on the target plane at radial positions increasing linearly with decreasing atomic mass units (amu).

Abstract: A system and method are disclosed for effectively compensating for non-linear field components created by a field distortion feature in a quadrupolar ion trap, compensation provided by a geometric surface shaping which reduces the non-linear field components and creates a minimal centerline radio-frequency potential in the ion trap. The ion trap includes a centerline that passes longitudinally through a trapping volume inside of the ion trap, a pair of Y electrodes with inner Y electrode surfaces that are approximately parallel to the centerline, and a pair of X electrodes with inner X electrode surfaces that are approximately parallel to the centerline. The X electrodes have one or more ejection slots through which trapped ions are ejected from said ion trap. The inner Y electrode surfaces each have a Y radius of curvature, and the inner X electrode surfaces each have an X radius of curvature. The X radius of curvature is selected to be smaller than the Y radius of curvature.

Abstract: A desired ion is isolated in an ion trapping volume by applying an ion isolation signal to a plurality of ions in the ion trapping volume, including the desired ion to be retained in the ion trapping volume and an undesired ion to be ejected from the ion trapping volume. The ion isolation signal includes a plurality of signal components spanning a frequency range. The plurality of signal components includes a first component having a frequency near a secular frequency of the desired ion, and an adjacent component having a frequency adjacent to the frequency of the first component. The first component has an amplitude greater than the amplitude of the adjacent component.

Abstract: Disclosed is an apparatus for separating ions including a plurality of first electrode portions, each first electrode portion of the plurality of first electrode portions having a first length and an outer surface that is at least partially curved in a direction transverse to the first length. The apparatus also includes a plurality of second electrode portions arranged in an alternating sequence with the plurality of first electrode portions, each second electrode portion of the plurality of second electrode portions having a second length and an outer surface that is curved in a direction transverse to the second length, a space between the outer surface of a first electrode portion and the outer surface of an adjacent second electrode portion defining a portion of an analytical gap for separating ions.

Abstract: A virtual ion trap that uses electric focusing fields instead of machined metal electrodes that normally surround the trapping volume, wherein two opposing surfaces include a plurality of uniquely designed and coated electrodes, and wherein the electrodes can be disposed on the two opposing surfaces using plating techniques that enable much higher tolerances to be met than existing machining techniques.

Abstract: A method of separating ions is disclosed. The method includes a step of providing a FAIMS analyzer region for separating ions, the FAIMS analyzer region including at least one region of segmentation. The segmentation permits ion trapping, and a combination trapping and gating that permits high efficiency of ions collection from continuous ion sources. The ions are separated in segmented FAIMS, according to their high-field mobility properties, and by using the method described herein according to their low-field mobility. The ions are separated by low field mobility using stationary potential gradients formed by voltages applied to the segments, and by traveling potential gradients of various shapes. The ions are separated along the longitudinal direction in cylindrical FAIMS, and may be detected in a time-of-arrival fashion as the ions leave the ion outlet of FAIMS or optionally the ions other than selected are caused to collide with the electrodes and only the selected ions transmitted.

Abstract: Apparatus and methods are provided for trapping, manipulation and transferring ions along RF and DC potential surfaces and through RF ion guides. Potential wells are formed near RF-field generating surfaces due to the overlap of the radio-frequency (RF) fields and electrostatic fields created by static potentials applied to surrounding electrodes. Ions can be constrained and accumulated over time in such wells. During confinement, ions may be subjected to various processes, such as accumulation, fragmentation, collisional cooling, focusing, mass-to-charge filtering, spatial separation ion mobility and chemical interactions, leading to improved performance in subsequent processing and analysis steps, such as mass analysis. Alternatively, the motion of ions may be better manipulated during confinement to improve the efficiency of their transport to specific locations, such as an entrance aperture into vacuum from atmospheric pressure or into a subsequent vacuum stage.

Abstract: A method and apparatus for trapping or guiding ions is provided. The ion trap or ion guide includes a first set of electrodes and a second set of electrodes, the first set of electrodes defining a first portion of an ion channel to trap or guide the introduced ions. In operation, periodic voltages are applied to electrodes in the first set of electrodes to generate a first oscillating electric potential that radially confines the ions in the ion channel, while periodic voltages are applied to electrodes in the second set of electrodes to generate a second oscillating electric potential that axially confines the ions in the ion channel.

Abstract: A system and method are disclosed for effectively compensating for an unbalanced or non-zero centerline radio-frequency potential in a quadrupolar ion trap, the unbalanced centerline potential created by a compensation feature that minimizes non-linear field components created by one or more ejection slots in the ion trap. The ion trap includes a centerline that passes longitudinally through a trapping volume inside of the ion trap, a pair of Y electrodes with inner Y electrode surfaces that are approximately parallel to the centerline, and a pair of X electrodes with inner X electrode surfaces that are approximately parallel to the centerline. The X electrodes have ejection slots through which trapped ions are ejected from the ion trap. A Y signal with a Y signal amplitude is coupled to both of the Y electrodes. An X signal with an X signal amplitude is coupled to both of the X electrodes.

Abstract: A method to increase low-energy beam current according to this invention is applied to an irradiation system with ion beam comprising a beam generation source, a mass analysis device, a beam transformer, a deflector for scanning, a beam parallelizing device, an acceleration/deceleration device, and an energy filtering device. The beam transformer comprises a vertically focusing DC quadrupole electromagnet QD and a longitudinally focusing DC quadrupole electromagnet QF. The beam transformer transforms a beam having a circular cross-section or an elliptical or oval cross-section to the beam has an elliptical or oval cross-section that is long in the scan direction in all the region of a beam line after deflection for scanning.

Abstract: A method and apparatus for multiplexing plural ion beams to a mass spectrometer. At least two ion sources are provided with means of transporting the ions from the ion sources to separate two-dimensional ion traps. Each ion trap is used for storage and transmission of the ions and operates between the ion sources and the mass analyzer. Each ion trap has a set of equally spaced, parallel multipole rods, as well as entrance and exit sections into which and from which ions enter and exit the trap, respectively. For each ion trap, the entrance section is placed in a region where background gas pressure is at viscous flow. The pressure at the exit section drops to molecular flow pressure regimes without a break in the structure of the ion trap. Each trap alternately stores and transmits ions by way of a fast voltage switch applied to the ion trap exit lens.

Abstract: An improved ion funnel design is disclosed that decreases the axial RF (parasite) fields at the ion funnel exit. This is achieved by addition of one or more compensation electrodes after the conductance limit electrode. Various RF voltage profiles may be applied to the various electrodes minimizing the parasite axial potential wells. The smallest RF aperture that serves as the conductance limiting electrode is further reduced over standard designs. Overall, the ion funnel improves transmission ranges of both low m/z and high m/z ions, reducing RF activation of ions and decreasing the gas load to subsequent differential pumping stages.

Abstract: This invention relates to a measuring cell for an Ion Cyclotron Resonance (ICR) spectrometer. The present invention provides a measurement cell for an FTMS spectrometer, comprising an excitation electrode arrangement positioned about a longitudinal axis which extends in a direction generally parallel to the field direction of an applied homogeneous magnetic field; and a trapping electrode arrangement, also positioned about the said longitudinal axis, for trapping ions longitudinally in the cell within a trapping region defined by the trapping electrode arrangement; wherein at least a part of the excitation electrode arrangement extends axially outwardly of the trapping region defined by the trapping electrode arrangement.