A lead-in electrode, of an orthogonal acceleration time-of-flight mass spectrometer, includes: a main body having an ion passing part and a first member including a main-body accommodating part that is a through-hole. One surface of the first member includes an extension part to define a position of one surface of the main body. A second member is attached to the first member. A through-hole is provided at a position of the second member. One surface of the second member includes a first area in contact with a surface opposite to the one surface of the first member and a second area located inside with respect to the first area. The second area is formed lower than a surface, of the first area, in contact with the surface opposite to the one surface. A lead-in electrode elastic member is disposed, in the second area, between the first member and second members.

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).

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.

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.

An analytical device includes: a first acceleration unit including a first acceleration electrode to which a pulse voltage for accelerating ions is applied; a flight tube; a second acceleration unit that is arranged between the first acceleration unit and the flight tube, and includes a second acceleration electrode to which a voltage for accelerating the ions is applied; an ion detector that detects the ions; and a capacitance adjustment unit that causes adjustment of a capacitance between at least one set of electrodes among a plurality of electrodes arranged in the first acceleration unit, the second acceleration unit, and a flight tube.

A drive unit for driving an acceleration electrode of amass spectrometer is disclosed. The drive unit includes a power converter comprising a switching element and pulsing circuitry that can form output pulses suitable for driving an acceleration electrode of amass spectrometer. The drive unit also includes a controller that is configured to synchronise operation of the switching element with the pulsing circuitry.

An analytical device includes: a first electrode to which a pulse voltage for accelerating ions is applied; at least one switching element that controls application of the pulse voltage to the first electrode; a second electrode that defines a space in which the ions fly; an ion detector that detects the ions; and a vacuum vessel that has the second electrode inside, wherein: the switching element is in contact with an insulator, and the insulator is in contact with the vacuum vessel.

The disclosure features methods and systems that include directing an ion beam to a region of a sample to liberate charged particles from the region of the sample, where the directed ion beam is pulsed at a first repetition rate, deflecting a first subset of the liberated charged particles from a first path to a second path different from the first path in response to a gate signal synchronized with the repetition rate of the pulsed ion beam, and detecting the first subset of the liberated charged particles in a time-of-flight (TOF) mass spectrometer to determine information about the sample, where the gate signal sets a common reference time for the TOF mass spectrometer for the first subset of charged particles liberated by each pulse of the ion beam.

An orthogonal acceleration time-of-flight mass spectrometer (1) includes: an ion ejector (123) which ejects measurement-target ions in a predetermined direction; an orthogonal accelerator (132) which accelerates ions in a direction orthogonal to the direction in which the ions are ejected; a ring electrode (131) located between the ion ejector and the orthogonal accelerator, the ring electrode having an opening for allowing ions to pass through and arranged so that the central axis (C2) of the opening is shifted from the central axis (C1) of the ion ejector in a direction along the axis of the acceleration of the ions by the orthogonal accelerator; a reflectron electrode (134) which creates a repelling electric field for reversing the direction of the ions accelerated by the orthogonal accelerator; and an ion detector (135) which detects ions after the direction of flight of the ions is reversed by the reflectron electrode.

Methods for confirming charged-particle generation in an instrument are provided. A method to confirm charged-particle generation in an instrument includes providing electrical connections to a charged-particle optics system of the instrument while the charged-particle optics system is in a chamber. The method includes coupling an electrical component having an impedance to charged-particle current generated in the chamber. Moreover, the method includes measuring an electrical response by the electrical component to the charged-particle current. Related instruments are also provided.