Micromass UK Limited

Leco Corporation

Mikhail Yavor

Anatoly Verenchikov

Keith George Richardson

John Brian Hoyes

Anatoli N Verentchikov

Anatoly N Verenchikov

Jason Lee Wildgoose

Viatcheslav Artaev

Joel C Mitchell

Timofey V Pomozov

Viatcheslav Arteav

Improved ion mirrors(FIG.) are proposed for multi-reflecting TOF MS and electrostatic traps. Minor and controlled variation by means of arranging a localized wedge field structureat the ion retarding region was found to produce major tilt of ion packets time fronts. Combining wedge reflecting fields with compensated deflectors is proposed for electrically controlled compensation of local and global misalignments, for improved ion injection and for reversing ion motion in the drift direction. Fine ion optical properties of methods and embodiments are verified in ion optical simulations.

Ion mirror for multi-reflecting mass spectrometers

Improved pulsed ion sources and pulsed converters are proposed for multi-pass time-of-flight mass spectrometer, either multi-reflecting (MR) or multi-turn (MT) TOF. A wedge electrostatic field () is arranged within a region of small ion energy for electronically controlled tilting of ion packets () time front. Tilt angle &#x3b3; of time front () is strongly amplified by a post-acceleration in a flat field (). Electrostatic deflector () downstream of the post-acceleration () allows denser folding of ion trajectories, whereas the injection mechanism allows for electronically adjustable mutual compensation of the time front tilt angle, i.e. &#x3b3;=0 for ion packet in location (), for curvature of ion packets, and for the angular energy dispersion. The arrangement helps bypassing accelerator () rims, adjusting ion packets inclination angles &#x3b1;and what is most important, compensating for mechanical misalignments of the optical components.

Accelerator for multi-pass mass spectrometers

Improved ion mirrors () (FIG.) are proposed for multi-reflecting TOF MS and electrostatic traps. Minor and controlled variation by means of arranging a localized wedge field structure () at the ion retarding region was found to produce major tilt of ion packets time fronts (). Combining wedge reflecting fields with compensated deflectors is proposed for electrically controlled compensation of local and global misalignments, for improved ion injection and for reversing ion motion in the drift direction. Fine ion optical properties of methods and embodiments are verified in ion optical simulations.

A multi-reflecting time-of-flight mass spectrometer MR TOF with an orthogonal accelerator () is improved with at least one deflector () and/or (R) in combination with at least one wedge field () for denser folding of ion rays (). Systematic mechanical misalignments () of ion mirrors () may be compensated by electrical tuning of the instrument, as shown by resolution improvements between simulated peaks for non compensated case () and compensated one (), and/or by an electronically controlled global electrostatic wedge/arc field within ion mirror ().

Fields for multi-reflecting TOF MS

A time-of-flight or electrostatic trap mass analyzer is disclosed comprising: an ion flight region comprising a plurality of ion-optical elements (-) for guiding ions through the flight region in a deflection (x-y) plane. The ion-optical elements are arranged so as to define a plurality of identical ion-optical cells, wherein the ion-optical elements in each ion-optical cell are arranged and configured so as to generate electric fields for either focusing ions travelling in parallel at an ion entrance location of the cell to a point at an ion exit location of the cell, or for focusing ions diverging from a point at the ion entrance location to travel parallel at the ion exit location. Each ion-optical cell comprises a plurality of electrostatic sectors having different deflection radii for bending the flight path of the ions in the deflection (x-y) plane. The ion-optical elements in each cell are configured to generate electric fields that either (i) have mirror symmetry in the deflection plane about a line in the deflection plane that is perpendicular to a mean ion path through the cell at a point half way along the mean ion path through the cell, or (ii) have point symmetry in the deflection plane about a point in the deflection plane that is half way along the mean ion path through the cell. The ion-optical elements are arranged and configured such that, in the frame of reference of the ions, the ions are guided through the deflection plane in the ion-optical cells along mean flight paths that are of the same shape and length in each ion-optical cell.

Mass analyser having extended flight path

A method of time-of-flight mass spectrometry is disclosed comprising: providing two ion mirrors () that are spaced apart in a first dimension (X-dimension) and that are each elongated in a second dimension (Z-dimension) orthogonal to the first dimension; introducing packets of ions () into the space between the mirrors using an ion introduction mechanism () such that the ions repeatedly oscillate in the first dimension (X-dimension) between the mirrors () as they drift through said space in the second dimension (Z-dimension); oscillating the ions in a third dimension (Y-dimension) orthogonal to both the first and second dimensions as the ions drift through said space in the second dimension (Z-dimension); and receiving the ions in or on an ion receiving mechanism () after the ions have oscillated multiple times in the first dimension (X-dimension); wherein at least part of the ion introduction mechanism () and/or at least part of the ion receiving mechanism () is arranged between the mirrors ().

Multi-reflecting TOF mass spectrometer

An ion mirror is disclosed comprising an ion entrance electrode section () at the ion entrance to the ion mirror, an energy focussing electrode section () for reflecting ions back along a longitudinal axis towards said ion entrance, and a spatial focussing electrode section () arranged between the ion entrance electrode section () and the energy focussing electrode section () for spatially focussing the ions. One or more DC voltage supply is provided to apply a DC potential to the ion entrance electrode section () that is intermediate the DC potential applied to the spatial focussing electrode section () and the DC potential applied to the energy focussing electrode section (). The ion mirror further comprises: (i) at least one first transition electrode () arranged between said ion entrance electrode section () and said spatial focussing electrode section (), wherein said one or more DC voltage supply is configured to apply a DC potential to said at least one first transition electrode that is intermediate the DC potential applied to the ion entrance electrode section () and the DC potential applied to the spatial focussing electrode section (); and (ii) at least one second transition electrode () arranged between said energy focussing electrode section () and said spatial focussing electrode section (), wherein said one or more DC voltage supply is configured to apply a DC potential to said at least one second transition electrode () that is intermediate the DC potential applied to the spatial focussing electrode section () and the DC potential applied to the ion entrance electrode section ().

Ion mirror and ion-optical lens for imaging

A time-of-flight mass spectrometer is disclosed comprising ion optics that map an array of ions at an ion source array () to a corresponding array of positions on a position sensitive ion detector (). The ion optics include at least one gridless ion mirror () for reflecting ions, which may compensate for various aberrations and allows the spectrometer to have relatively high mass and spatial resolutions.

Imaging mass spectrometer

A time-of-flight mass spectrometer is disclosed comprising: an ion deflector () configured to deflect ions to different positions in a first array of positions at different times; a position sensitive ion detector (); and ion optics () arranged and configured to guide ions from the first array of positions to the position sensitive detector () so as to map ions from the first array of positions to a second array of positions on the position sensitive detector (); wherein the ion optics includes at least one ion mirror for reflecting the ions.

A multi-reflecting time-of-flight mass spectrometer comprises a pair of parallel aligned ion mirrors and a set of periodic lenses for confining ion packets along the drift z-direction. To compensate for time-of-flight spherical aberrations T|zz created by the periodic lenses, at least one set of electrodes are disposed within the apparatus, forming an accelerating or reflecting electrostatic fields which are curved in the z-direction in order to form local negative T|zz aberration. The structure may be formed within an accelerator, within flinging fields or intentionally and locally curved fields of ion mirrors, within electrostatic sector interface, or at curved surface of ion to electron converter at the detector.

Multi-reflecting time-of-flight analyzer

A multi-reflecting, time-of-flight (MR-TOF) mass spectrometer including two quasi-planar electrostatic ion mirrors extended along drill direction (Z) and formed of parallel electrodes, separated by a field free region. The MR-TOF includes a pulsed ion source to release ion packets at a small angle to X-direction which is orthogonal to the drill direction Z. Ion packets are reflected between ion mirrors and drill along the drift direction. The mirrors are arranged to provide time-of-flight focusing ion packets on the receiver. The MR-TOF mirrors provide spatial focusing M the Y-direction orthogonal to both drift direction Z and on injection direction X. In a preferred embodiment, at least one mirror has a feature providing periodic spatial focusing of ion packets in the drift Z-direction.

Quasi-planar multi-reflecting time-of-flight mass spectrometer

To improve spatial and energy acceptance of multi-reflecting time-of-flight, open traps, and electrostatic trap analyzers, a novel ion mirror is disclosed. Incorporation of immersion lens between ion mirrors allows reaching the fifth order time per energy focusing simultaneously with the third order time per spatial focusing including energy-spatial cross terms. Preferably the analyzer has hollow cylindrical geometry for extended flight path. The time-of-flight analyzer preferably incorporates spatially modulated ion mirror field for isochronous ion focusing in the tangential direction.

Multi-reflecting mass spectrometer

A multi-reflecting time-of-flight (MR-TOF) mass spectrometer, which includes two quasi-planar electrostatic ion mirrors extended along drift direction (Z) and is formed of parallel electrodes, separated by a field-free region. The MR-TOF includes a pulsed ion source to release ion packets at a small angle to X-direction which is orthogonal to the drift direction Z. Ion packets are reflected between ion mirrors and drift along the drift direction. The mirrors are arranged to provide time-of-flight focusing ion packets on the receiver. The MR-TOF mirrors provide spatial focusing in the Y-direction orthogonal to both drift direction Z and ion injection direction X. In a preferred embodiment, at least one mirror has a feature providing periodic spatial focusing of ion packets in the drift Z-direction.

An electrostatic ion mirror is disclosed providing fifth order time-per-energy focusing. The improved ion mirror has up to 18% energy acceptance at resolving power above 100,000. Multiple sets of ion mirror parameters (shape, length, and voltage of electrodes) are disclosed. Highly isochronous fields are formed with improved (above 10%) potential penetration from at least three electrodes into a region of ion turning. Cross-term spatial-energy time-of-flight aberrations of such mirrors are further improved by elongation of electrode with attracting potential or by adding a second electrode with an attracting potential.

Growing community of inventors

St. Petersburg, Russia

Mikhail Yavor