Patent classifications
H01J49/403
ION TRAP
An ion trap having a segmented electrode structure having a plurality of segments consecutively positioned along an axis, wherein each segment of the segmented electrode structure includes a plurality of electrodes arranged around the axis. A first voltage supply is configured to operate in a radially confining mode in which at least some electrodes belonging to each segment are supplied with at least one AC voltage waveform so as to provide a confining electric field for radially confining ions within the segment. A second voltage supply is configured to operate in a trapping mode in which at least some of the electrodes belonging to the segments are supplied with different DC voltages so as to provide a trapping electric field that has an axially varying profile for urging ions towards and trapping ions in a target segment of the plurality of segments. A first chamber is configured to receive ions from an ion source, wherein a first subset of the segments are located within the first chamber. A second chamber is configured to receive ions from the first chamber, wherein a second subset of the segments are located within the second chamber, and wherein the target segment is one of the second subset of segments. A gas pump is configured to pump gas out from the second chamber so as to provide the second chamber with a lower gas pressure than the first chamber. A gas flow restricting section is located between the first chamber and second chamber, wherein the gas flow restricting section is configured to allow ions to pass from the first chamber to the second chamber whilst restricting gas flow from the first chamber to the second chamber.
Time of flight mass spectrometer
A time of flight mass spectrometer that includes a first electrode; and a second electrode that is spaced apart from the first electrode. The ion source is configured to apply voltages to the first and second electrodes to produce an electric field in a region between the first and second electrodes so as to influence ions present in the region between the first and second electrodes when the mass spectrometer is in use. A shield is formed on the first electrode and/or second electrode. The shield is configured to inhibit an electric field formed between edges of the first and second electrodes from penetrating into the region between the first and second electrodes when the mass spectrometer is in use.
WIDE-RANGE HIGH MASS RESOLUTION IN REFLECTOR TIME-OF-FLIGHT MASS SPECTROMETERS
The invention relates to the operation of an energy-focusing and solid-angle-focusing reflector for time-of-flight mass spectrometers with pulsed ion acceleration into a flight tube, e.g. from an ion source with ionization by matrix-assisted laser desorption (MALDI). The objective of the invention is to generate high mass resolution in wide mass ranges up to high masses above eight kilodaltons by varying at least one operating voltage on one of the diaphragms of the reflector which can be varied according to a suitable time function during the spectrum acquisition. It may also be advantageous to adapt the operation of the accelerating voltages in the starting region of the ions accordingly. These measures make it possible to achieve a mass resolution much higher than R=100,000 in a wide mass range extending up to and above eight kilodaltons.
TIME-OF-FLIGHT MASS SPECTROMETER AND TIME-OF-FLIGHT MASS SPECTROMETRY METHOD
A TOFMS includes flight space formation electrodes, an ion detection unit, voltage switching units to switch a voltage to be applied to the flight space formation electrode from a first voltage for flying ions of a first polarity to a second voltage for flying ions of a second polarity, ion information acquisition units to obtain a time of flight or a m/z of the ions based on a detection result of the ions of the second polarity after the voltage has been switched, a correction information storage unit to store correction information related to a deviation in time of flight or a m/z associated with an elapsed time from the switching timing, and a correction unit to correct the flight time or the m/z according to an elapsed time from the switching timing when the detection result of the ion is obtained using the correction information.
APPARATUS FOR TRAPPING IONS
Apparatuses for trapping ions comprise an array of electrodes extending along a surface and one or more further electrodes that are distinct from the array of electrodes. A trapping region for receiving the ions is defined by the array of electrodes and the one or more further electrodes. A control circuit is configured to apply a set of oscillatory voltages to the array of electrodes to repel the ions, wherein each electrode in the array has a different phase to each adjacent electrode. A trapping voltage is applied to at least one of the one or more further electrodes to force the ions towards the array of electrodes, the set of oscillatory voltages and the trapping voltage thereby trapping the ions within the trapping region, wherein the trapping voltage is a time-varying direct current, DC, voltage that increases in magnitude over time.
ION OPTICAL DEVICE
An ion optical device includes one or more pairs of confinement electrode units arranged at two sides of a first direction; a power supply device for applying opposite radio-frequency voltages to the paired confinement electrode units respectively and forming thereon DC potentials distributed in a second direction orthogonal to the first direction to form a potential barrier herein over a length portion of the first direction; one first area and one second area positioned at two sides of the potential barrier in the second direction; and a control device connected with the power supply device for controlling an output to change the potential barrier to manipulate the ions transported/stored in the first area being transferred to the second area through the potential barrier in ways based on the mass to charge ratio or mobility of the ions and continue being transported along the first direction.
ORTHOGONAL ACCELERATION TIME-OF-FLIGHT MASS SPECTROMETRY
A multipole ion guide (30) including a plurality of rod electrodes arranged at an angle to the central axis (C) is placed within a collision cell (13) located in the previous stage of an orthogonal accelerator (16). Radio-frequency voltages with opposite phases are applied to the rod electrodes of the ion guide (30) so that any two rod electrodes neighboring each other in the circumferential direction have opposite phases of the voltage. A depth gradient of the pseudopotential is thereby formed from the entrance end toward the exit end within the space surrounded by the rod electrodes, and ions are accelerated by this gradient. During an ion-accumulating process, a direct voltage having the same polarity as the ions is applied to the exit lens electrode (132) to form a potential barrier for accumulating ions. Among the ions repelled by the potential barrier, ions having smaller m/z return closer to the entrance end. Therefore, when the potential barrier is removed and ions are discharged, ions having smaller m/z are discharged at later points in time than those having larger m/z. Therefore, a wide m/z range of ions can be simultaneously accelerated and ejected by an orthogonal accelerator (16).
MASS SPECTROMETER WITH A LASER DESORPTION ION SOURCE, AND LASER SYSTEM WITH A LONG SERVICE LIFE
The invention relates to a mass spectrometer with laser-desorption ion source, particularly for MALDI. A laser system with optical laser spot control is proposed in which the laser spot shift brought about by means of a temporally variable angular deflection at a mirror system is performed on the laser beam before or during the energy multiplication. The laser beam, which is deflected through a small angle by the mirror system, is converted by a suitable flat-field optical system into a parallel-shifted laser beam, which then passes through a multiplier crystal. After exiting the multiplier crystal system, the parallel-shifted beam is converted back into a slightly angled beam by a flat-field optical system, this latter beam then bringing about the spot shift on the sample. The multiplier crystal is conserved by the continuously temporally changed parallel shift of the laser beam in the multiplier crystal, thus prolonging its service life.
MASS SPECTROMETER AND METHOD FOR TIME-OF-FLIGHT MASS SPECTROMETRY
A mass spectrometer comprising: a pulsed ion source for generating pulses of ions having a range of masses; a time-of-flight mass analyzer for receiving and mass analyzing the pulses of ions from the ion source; and an energy controlling electrode assembly located between the pulsed ion source and the time-of-flight mass analyzer configured to receive the pulses of ions from the pulsed ion source and apply a time-dependent potential to the ions thereby to control the energy of the ions depending on their m/z before they reach the time-of-flight mass analyzer. Mass dependent differences in average energy of ions can be reduced for injection into a time-of-flight mass analyzer, which can improve ion transmission and/or instrument resolving power.
MALDI-TOF MASS SPECTROMETERS WITH DELAY TIME VARIATIONS AND RELATED METHODS
MALDI-TOF MS systems have solid state lasers and successive and varied delay times between ionization and acceleration (e.g. extraction) to change focus masses during a single sample signal acquisition without requiring tuning of the MS by a user. The (successive) different delay times can change by 1 ns to about 500 ns, and can be in a range that is between 1-2500 nanoseconds.