Disclosed is a spectrometry method including: for at least one ionizing-radiation energy E.sub.i, obtaining, for each energy E.sub.i, a curve of the number of photons detected, during a measurement interval, as a function of time, by spectrometer; b) for each curve, computing a ratio of the number of photons detected defined and separate time periods to obtain, for each ionizing-radiation energy E.sub.i, a number a.sub.i, or for each curve, acquiring one or more fitting parameters PAJ.sub.i by making a fit to the corresponding curve with a fitting function; and comparing each number a.sub.i or each fitting parameter or set of fitting parameters PAJ.sub.i with reference constants a.sub.i or, respectively, with reference fitting parameters PAJ.sub.i associated with reference energies E.sub.i to determine, for each number a.sub.i or each fitting parameter or set of fitting parameters PAJ.sub.i, reference energy E.sub.i of the ionizing radiation for which the corresponding curve was measured.

Disclosed is a spectrometry method including: for at least one ionizing-radiation energy E.sub.i, obtaining, for each energy E.sub.i, a curve of the number of photons detected, during a measurement interval, as a function of time, by spectrometer; b) for each curve, computing a ratio of the number of photons detected defined and separate time periods to obtain, for each ionizing-radiation energy E.sub.i, a number a.sub.i, or for each curve, acquiring one or more fitting parameters PAJ.sub.i by making a fit to the corresponding curve with a fitting function; and comparing each number a.sub.i or each fitting parameter or set of fitting parameters PAJ.sub.i with reference constants a.sub.i or, respectively, with reference fitting parameters PAJ.sub.i associated with reference energies E.sub.i to determine, for each number a.sub.i or each fitting parameter or set of fitting parameters PAJ.sub.i, reference energy E.sub.i of the ionizing radiation for which the corresponding curve was measured.

A method of using a Transmission Charged Particle Microscope comprising: A specimen holder, for holding a specimen; A source, for producing a beam of charged particles; An illuminator, for directing said beam so as to irradiate the specimen; An imaging system, for receiving a flux of charged particles transmitted through the specimen and directing it onto a sensing device; A controller, for controlling at least some operational aspects of the microscope,
in which method the sensing device is chosen to be an EELS/EFTEM module comprising: An entrance plane; An image plane, where in EELS mode an EELS spectrum is formed and in EFTEM mode an EFTEM image is formed; A slit plane between said entrance plane and image plane, where in EFTEM mode an energy dispersed focus is formed; A dispersing device, between said entrance plane and slit plane, for dispersing an incoming beam into an energy-dispersed beam with an associated dispersion direction; A first series of quadrupoles between said dispersing device and slit plane; A second series of quadrupoles between said slit plane and image plane,
which dispersing device and quadrupoles are arranged along an optical axis,
whereby, for a Cartesian coordinate system (X,Y,Z) in which said optical axis is disposed along Z, said dispersion direction is defined as being parallel to X,
comprising the following steps: In said first quadrupole series, exciting one or more quadrupoles so as to deflect an off-axis non-dispersive YZ ray leaving said dispersing device onto a path paraxial to said optical axis from said slit plane to said image plane; In said second quadrupole series, exciting either: (a) A single quadrupole; or (b) A pair of adjacent quadrupoles, so as to focus said energy-dispersed beam onto said image plane.

A method of using a Transmission Charged Particle Microscope comprising: A specimen holder, for holding a specimen; A source, for producing a beam of charged particles; An illuminator, for directing said beam so as to irradiate the specimen; An imaging system, for receiving a flux of charged particles transmitted through the specimen and directing it onto a sensing device; A controller, for controlling at least some operational aspects of the microscope,
in which method the sensing device is chosen to be an EELS/EFTEM module comprising: An entrance plane; An image plane, where in EELS mode an EELS spectrum is formed and in EFTEM mode an EFTEM image is formed; A slit plane between said entrance plane and image plane, where in EFTEM mode an energy dispersed focus is formed; A dispersing device, between said entrance plane and slit plane, for dispersing an incoming beam into an energy-dispersed beam with an associated dispersion direction; A first series of quadrupoles between said dispersing device and slit plane; A second series of quadrupoles between said slit plane and image plane,
which dispersing device and quadrupoles are arranged along an optical axis,
whereby, for a Cartesian coordinate system (X,Y,Z) in which said optical axis is disposed along Z, said dispersion direction is defined as being parallel to X,
comprising the following steps: In said first quadrupole series, exciting one or more quadrupoles so as to deflect an off-axis non-dispersive YZ ray leaving said dispersing device onto a path paraxial to said optical axis from said slit plane to said image plane; In said second quadrupole series, exciting either: (a) A single quadrupole; or (b) A pair of adjacent quadrupoles, so as to focus said energy-dispersed beam onto said image plane.

A hybrid ion mobility spectrometer includes a single-pass drift tube having an ion inlet and an ion outlet, a multiple-pass drift tube having an ion inlet and an ion outlet each coupled to the single pass drift tube between the ion inlet and the ion outlet thereof, and at least one ion steering channel controllable to selectively pass ions traveling through the single-pass drift tube into the multiple-pass drift tube via the ion inlet of the multiple-pass drift tube and to selectively pass ions traveling through the multiple-pass drift tube into the single-pass drift tube via the ion outlet of the multiple-pass drift tube. The single-pass drift tube separates in time ions traveling therethrough according to a first function of ion mobility, and the multiple-pass drift tube separates in time ions traveling one or more times therethrough according to the first or a second function of ion mobility.

A method of performing Electron Energy-Loss Spectroscopy (EELS) in an electron microscope, comprising: Producing a beam of electrons from a source; Using an illuminator to direct said beam so as to irradiate the specimen; Using an imaging system to receive a flux of electrons transmitted through the specimen and direct it onto a spectroscopic apparatus comprising: A dispersion device, for dispersing said flux in a dispersion direction so as to form an EELS spectrum; and A detector, comprising a detection surface that is sub-divided into a plurality of detection zones,

specifically comprising: Using at least a first detection zone, a second detection zone and a third detection zone to register a plurality of EELS spectral entities; and Reading out said first and said second detection zones whilst said third detection zone is registering one of said plurality of EELS spectral entities.

A method of performing Electron Energy-Loss Spectroscopy (EELS) in an electron microscope, comprising: Producing a beam of electrons from a source; Using an illuminator to direct said beam so as to irradiate the specimen; Using an imaging system to receive a flux of electrons transmitted through the specimen and direct it onto a spectroscopic apparatus comprising: A dispersion device, for dispersing said flux in a dispersion direction so as to form an EELS spectrum; and A detector, comprising a detection surface that is sub-divided into a plurality of detection zones,

specifically comprising: Using at least a first detection zone, a second detection zone and a third detection zone to register a plurality of EELS spectral entities; and Reading out said first and said second detection zones whilst said third detection zone is registering one of said plurality of EELS spectral entities.

Each of one or more unknown compounds are separated from a sample over a separation time period. Separated compounds are ionized, producing one or more compound precursor ions for each of the unknown compounds and a plurality of background precursor ions. A precursor ion mass spectrum is measured for the combined compound and background precursor ions at each time step of a plurality of time steps spread across the separation time period, producing a plurality of precursor ion mass spectra. One or more background precursor ions are selected from the plurality of precursor ion mass spectra that have a resolving power in a range below a threshold expected resolving power. A separation time is detected for an unknown compound when a decrease in an intensity measurement of the selected background precursor ions over a time period exceeds a threshold decrease in intensity with respect to time.

A method of using a Transmission Charged Particle Microscope comprising:

A specimen holder, for holding a specimen;

A source, for producing a beam of charged particles;

An illuminator, for directing said beam so as to irradiate the specimen;

An imaging system, for receiving a flux of charged particles transmitted through the specimen and directing it onto a sensing device;

A controller, for controlling at least some operational aspects of the microscope, in which method the sensing device is chosen to be an EELS/EFTEM module comprising:

An entrance plane;

An image plane, where in EELS mode an EELS spectrum is formed and in EFTEM mode an EFTEM image is formed;

A slit plane between said entrance plane and image plane, where in EFTEM mode an energy dispersed focus is formed;

A dispersing device, between said entrance plane and slit plane, for dispersing an incoming beam into an energy-dispersed beam with an associated dispersion direction;

A first series of quadrupoles between said dispersing device and slit plane;

A second series of quadrupoles between said slit plane and image plane, which dispersing device and quadrupoles are arranged along an optical axis, whereby, for a Cartesian coordinate system (X,Y,Z) in which said optical axis is disposed along Z, said dispersion direction is defined as being parallel to X,

comprising the following steps:

In said first quadrupole series, exciting one or more quadrupoles so as to deflect an off-axis non-dispersive YZ ray leaving said dispersing device onto a path paraxial to said optical axis from said slit plane to said image plane;

In said second quadrupole series, exciting either: (a) A single quadrupole; or (b) A pair of adjacent quadrupoles, so as to focus said energy-dispersed beam onto said image plane.

A method of using a Transmission Charged Particle Microscope comprising:

A specimen holder, for holding a specimen;

A source, for producing a beam of charged particles;

An illuminator, for directing said beam so as to irradiate the specimen;

An imaging system, for receiving a flux of charged particles transmitted through the specimen and directing it onto a sensing device;

A controller, for controlling at least some operational aspects of the microscope, in which method the sensing device is chosen to be an EELS/EFTEM module comprising:

An entrance plane;

An image plane, where in EELS mode an EELS spectrum is formed and in EFTEM mode an EFTEM image is formed;

A slit plane between said entrance plane and image plane, where in EFTEM mode an energy dispersed focus is formed;

A dispersing device, between said entrance plane and slit plane, for dispersing an incoming beam into an energy-dispersed beam with an associated dispersion direction;

A first series of quadrupoles between said dispersing device and slit plane;

A second series of quadrupoles between said slit plane and image plane, which dispersing device and quadrupoles are arranged along an optical axis, whereby, for a Cartesian coordinate system (X,Y,Z) in which said optical axis is disposed along Z, said dispersion direction is defined as being parallel to X,

comprising the following steps:

In said first quadrupole series, exciting one or more quadrupoles so as to deflect an off-axis non-dispersive YZ ray leaving said dispersing device onto a path paraxial to said optical axis from said slit plane to said image plane;

In said second quadrupole series, exciting either: (a) A single quadrupole; or (b) A pair of adjacent quadrupoles, so as to focus said energy-dispersed beam onto said image plane.