A constructed unit is fixed to a base by means of a plurality of support posts while being spaced from the base. The constructed unit includes an orthogonal acceleration unit. An incidence regulator unit is fixed to the base by a pair of support posts while being spaced from the base and the constructed unit. The incidence regulator unit includes, among others, a pair of blades that define a slit, and heaters for heating the pair of blades.

Apparatus comprise an electrode arrangement comprising a plurality of electrodes defining a volume, an ion entrance, and an ion exit, and a voltage source coupled to the plurality of electrodes and configured to apply a nonlinear DC voltage sequence to the electrodes between the ion entrance and the ion exit that directs ions through the volume with the volume at a pressure of at least 1 Torr. Ions can be focused using nonlinear DC voltage sequences, including at atmospheric pressure. Related methods are also disclosed.

A MALDI ion source for tandem mass spectrometers includes a pulsed energy source that generates a pulse of ions from a sample on a sample plate. An ion accelerator includes an input that receives the pulse of ions from the pulsed energy source and generates an electric field that accelerates the pulse of ions. An ion decelerator that generates an electric field that is a mirror image of the electric field generated by the ion accelerator that accelerates the pulse of ions so that the ion decelerator decelerates the accelerated pulse of ions and transmits the decelerated pulse of ions through an exit aperture.

A Time of Flight analyser comprising a flight tube (160) and a reflectron (170), wherein the reflectron comprises a stack of electrodes (172) that are compressed against the flight tube such that they remain parallel to each other under compression.

A mass spectrometer comprising: a multi-reflecting time of flight (MRTOF) mass analyser or mass separator having two gridless ion mirrors 2 that are elongated in a first dimension (Z-dimension) and configured to reflect ions multiple times in a second orthogonal dimension (X-dimension) as the ions travel in the first dimension; the spectrometer configured to operate in: (i) a first mode for ions having a first rate of interaction with background gas molecules in the mass analyser or separator, such that the ions are reflected a first number of times between the ion mirrors 2; and (ii) a second mode for ions having a second, higher rate of interaction with background gas molecules in the mass analyser or separator, such that ions are reflected a second, lower number of times between the ion mirrors 2.

An acceleration voltage generator (7) generates a high-voltage pulse to be applied to an electrode in an orthogonal accelerator by turning on/off a high DC voltage generated by a high-voltage power source through MOSFETs (741) in a switch circuit (74). A controller (6) sends driving pulse signals to the switch circuit (74) through a primary-side driver section (71), transformer (72) and secondary driver section (73). An adjustment circuit (742) formed by a gate resistor (742a) and gate capacitor (742b) is provided between the secondary-side driver section (73) and the MOSFET (741). The resistance value of the resistor (742a) and the capacitance value of the capacitor (742b) are determined so as to suppress an overshoot of the gate voltage due to the resonance while preventing a decrease in steepness of the waveform in its rising and falling phases.

A time-of-flight (ToF) mass spectrometer, comprising: a pulsed ion injector for forming an ion beam that travels along an ion path; a detector for detecting ions in the ion beam that arrive at the detector at times according to their m/z values; an ion focusing arrangement located between the ion injector and the detector for focusing the ion beam in at least one direction orthogonal to the ion path; and a variable voltage supply for supplying the ion focusing arrangement with at least one variable voltage that is dependent on a charge state and/or an amount of ions of at least one species of ions in the ion beam. A corresponding method of mass spectrometry is provided. The charge state and/or an amount of ions may be acquired from a pre-scan, or predicted. Tuning of the spectrometer based on a charge state and/or an amount of ions of at least one species of ions in the ion beam may be performed on the fly.

The invention provides a method for acquiring as many fragment mass spectra of selected substances, e.g. proteins, of complex mixtures, as possible using a hybrid mass spectrometric system which comprises an ion source, an ion mobility separator, a mass filter, a fragmentation cell, and a mass analyzer. The fragment mass spectra are used for identifying the substances by their fragment mass spectra. The invention proposes to control the dwell time of the mass filter and to adapt the dwell time to the length of the ion mobility signal in a mass-mobility map.

An ion detection system is disclosed that comprises one or more first devices (11) configured to produce secondary electrons in response to incident ions. The one or more first devices (11) comprise a first ion collection region and a second ion collection region and are configured to produce first secondary electrons in response to one or more ions incident at the first ion collection region and to produce second secondary electrons in response to one or more ions incident at the second ion collection region. The ion detection system also comprises a first output device (14) configured to output a first signal in response to first secondary electrons produced by the one or more first devices (11) and a second output device (15) configured to output a second signal in response to second secondary electrons produced by the one or more first devices (11).

A drive unit for driving an acceleration electrode of a mass 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 a mass spectrometer. The drive unit also includes a controller that is configured to synchronise operation of the switching element with the pulsing circuitry.