A method of spectrometric analysis comprises obtaining one or more sample spectra for an aerosol, smoke or vapour sample. The one or more sample spectra are subjected to pre-processing and then multivariate and/or library based analysis so as to classify the aerosol, smoke or vapour sample. The results of the analysis are used for various surgical or non-surgical applications.

A method for determining a compensation factor parameter, c, for controlling an amount of ions ionised that are injected from an ion storage unit into mass analyser, where c is an adjustment factor that is applied to optimized injection times that are based on an optimized visible charge of a reference sample, the method comprising: detecting at least one mass spectrum for at least one amount of injected ions; determining from the at least one detected mass spectrum, a slope, s(sample), of a linear correlation of a relative m/z shift with visible total charge Q.sub.v of detected mass spectra; determining the compensation factor c as c=s(reference)/s(sample) where s(reference) is the slope of a linear correlation between reference-sample relative m/z shift values and reference-sample visible charge values determined from a plurality of mass spectra detected from a plurality of respective pre-selected amounts of a clean reference sample.

A CDMS may include an ELIT having a charge detection cylinder (CD), a charge generator for generating a high frequency charge (HFC), a charge sensitive preamplifier (CP) having an input coupled to the CD and an output configured to produce a charge detection signal (CHD) in response to a charge induced on the CD, and a processor configured to (a) control the charge generator to induce an HFC on the CD, (b) control operation of the ELIT to cause a trapped ion to oscillate back and forth through the CD each time inducing a charge thereon, and (c) process CHD to (i) determine a gain factor as a function of the HFC induced on the CD, and (ii) modify a magnitude of the portion of CHD resulting from the charge induced on the CD by the trapped ion passing therethrough as a function of the gain factor.

An ion analyzer includes an ion optical element having four rod electrodes around an optical axis, for transferring ions from their surrounding space to the subsequent stage while converging the ions. To create an RF electric field within this space, a voltage supplier applies RF voltages of opposite polarities to two pairs of electrodes facing each other across the axis. The cross-sectional shape of each electrode in a plane orthogonal to the axis has a first side having width w facing the axis and is tangent to a circle of radius r.sub.0 around the axis, and two adjacent sides connected to the ends of the first side at an angle determined so that an RF field created by the adjacent sides exerts no influence within the space. The ratio w/r.sub.0 is determined so that the amount of dodecapole field component becomes a predetermined value or does not exceed it.

A method of gain calibration for an ion detector operating at a detector voltage is described. The method includes steps of: generating single ions; determining a parameter of a first relationship between a detector output of an ion detector and a number of ions for a first detector voltage; detecting an ion peak at the ion detector using the first detector voltage; adjusting the detector voltage; and determining a parameter of a second relationship between the detector output and the number of ions for the second detector voltage. A system including a mass spectrometer arrangement and a controller configured to operate the mass spectrometer arrangement in accordance with this method is also described.

An ion detector according to this embodiment has a structure for reducing influences of signal reflection or the like on an output signal. The ion detector comprises an electron multiplier, a signal output unit, a signal output terminal, and an AC coupler. The AC coupler is disposed on a signal line between the signal output unit and the signal output terminal, including a resin sheet and a pair of conductive sections facing each other with the resin sheet interposed therebetween. One conductive section is electrically connected to an output terminal of the signal output unit, and the other conductive section is electrically connected to the signal output terminal.

The disclosure features mass spectrometry systems and methods that include an ion source, an ion trap, a detector subsystem featuring first and second detector elements, and a controller electrically connected to the ion source, the ion trap, and the detector subsystem and configured so that during operation of the system, the controller: applies an electrical signal to the ion source to generate positively and negatively charged particles from sample particles in the system; applies an electrical signal to the ion trap to eject a plurality of particles from the ion trap through a common aperture of the ion trap, and determines information about the sample particles based on first and second electrical signals generated by the ejected particles.

An ion detection system comprising an upper plate configured for propagation of ions therethrough, a lower plate comprising a converter configured for converting ions impinging thereon to secondary electrons, a secondary electron multiplication assembly configured for receiving the secondary electrons and comprising at least one or optionally a series of oppositely facing pairs of dynodes, wherein in the optional series of oppositely facing pairs of dynodes, each pair is spaced apart from an adjacent pair, and wherein a first electric field is created in between the oppositely facing pair of dynodes. A magnetic system is provided for generating a magnetic field.