Abstract: A method of determining a peak intensity in an optical spectrum is described. The method includes producing a two-dimensional array of spectrum values by imaging the optical spectrum onto a detector array. An offset using an actual location and an expected location of a peak of an interpolated subarray is used to adjust an expected location of another peak that is within another two-dimensional subarray. Interpolated spectrum values are then used to produce a peak intensity value of the second peak.

Abstract: A multipass cell (300) comprising: a first reflector arrangement (305A, 305B); and a second reflector arrangement (307), the first (305A, 305B) and second (307) reflector arrangements defining an optical cavity (315) therebetween and the cell; wherein the first reflector arrangement (305A, 305B) is configured such that light incident on the first reflector arrangement (305A, 305B) is at least partially retroreflected towards the second reflector arrangement (307), wherein the second reflector (307) arrangement comprises a concave surface that is reflective, wherein at least one of the first (305A, 305B) and second (307) reflector arrangements comprises an aperture (306) for allowing light to enter and/or exit the optical cavity (315).

Abstract: A method for compositional analysis, in particular laser-induced breakdown spectroscopy (LIBS), includes providing a sample having a surface, moving an ablation point to a plurality of positions on the surface along an arc path defined by a plurality of arcs, wherein the plurality of arcs extend from an edge of the area to another edge of the area, wherein the arc path follows adjacent arcs of the plurality of arcs, pulsing an energy source to provide an electromagnetic energy beam to ablate material at the ablation point, collecting an emission spectrum in response to pulsing the energy source, and analyzing the emission spectrum to determine a composition at the surface.

Abstract: A method for compositional analysis includes providing a sample having a surface, moving an ablation point to a plurality of positions on the surface along a fractal path, pulsing an energy source to provide an electromagnetic energy beam to ablate material at the ablation point, collecting an emission spectrum in response to pulsing the energy source, and analyzing the emission spectrum to determine a composition at the surface.

Abstract: A method for compositional analysis includes providing a sample having a surface and determining with a controller a plurality of equidistant positions along an oscillatory path along the surface. The oscillatory path is sinusoid in at least one orthogonal dimension within a plane approximately parallel to the surface. The method further includes, for each equidistant position of the plurality of equidistant position, moving an ablation point along the oscillatory path to the each equidistant position, pulsing an energy source to provide an electromagnetic energy beam to ablate material at the ablation point, and collecting an emission spectrum with a spectrographic instrument in response to pulsing the energy source. The method also includes analyzing the emission spectrum to determine a composition at the surface.

Abstract: A controller (316) and method for establishing safe operation of an atomic emission spectrometer (AES) to analyze a sample (100) arranged on a sample holder (102) of the AES. The controller (316) is configured to receive a measurement of at least one test parameter indicative of the arrangement of the sample (100) on the sample holder (102). The at least one test parameter is then compared to a range of target values for that test parameter to determine if the sample (100) is arranged correctly on the sample holder (102). The test parameters may include an electrical parameter dependant on a current between a first and a second terminal at the sample holder (102), gas pressure in a gas chamber housing an electrode of the AES, or displacement of a portion of the sample holder.

Abstract: A spark optical emission spectrometer comprising: a spark source for causing spark induced emission of light from a sample; a single entrance slit; a toroidal mirror for directing the light through the single entrance slit; a plurality of diffraction gratings for diffracting light that has been directed through the entrance slit by the mirror, whereby the plurality of diffraction gratings are simultaneously illuminated; and at least one array detector for detecting the diffracted light from the plurality of diffraction gratings, wherein the minor is for directing the light through the entrance slit such that light from different regions in the spark source is spatially separated in an image of the light at the gratings whereby a first diffraction grating is preferentially illuminated with light from a first region of the spark source and simultaneously a second diffraction grating is preferentially illuminated with light from a second region of the spark source.

Abstract: A spark chamber for an optical emission analyser, comprising: a gas inlet located on a first side of the spark chamber for supplying a gas into the spark chamber; and a gas outlet located on a second side of the spark chamber arranged to convey the gas from the spark chamber; wherein an elongated electrode having an electrode axis generally along the direction of elongation is located within the spark chamber; and wherein: the first and second sides of the spark chamber lie at either side of the elongated electrode in directions generally perpendicular to the electrode axis; there is a gas flow axis through the spark chamber between the gas inlet and the gas outlet; and on passing along the gas flow axis from the gas inlet to the gas outlet the unobstructed internal cross sectional area of the spark chamber perpendicular to the gas flow axis remains constant to within a factor A, wherein A lies between 1.0 and 2.

Abstract: The invention provides an apparatus and a method of performing X-ray diffraction (XRD) and/or X-ray fluorescence (XRF) analysis of a sample, comprising: irradiating a sample with X-rays from an X-ray source; providing a combined XRD and XRF detection arrangement comprising a scanning wavelength selector and at least one X-ray detector for detecting X-rays selected by the wavelength selector; and performing XRD analysis of the sample by selecting at least one fixed wavelength of X-rays diffracted by the sample using the scanning wavelength selector and detecting X-rays of the selected fixed wavelength(s) at one or more values of the diffraction angle ? at the sample using the X-ray detector(s); and/or performing XRF analysis of the sample by scanning wavelengths of X-rays emitted by the sample using the scanning wavelength selector and detecting X-rays of the scanned wavelengths using the X-ray detector(s).

Abstract: The invention provides a spark generator for generating a spark for optical emission spectroscopy (OES), wherein the spark has a current waveform comprising a first modulated portion which comprises a plurality of relatively high current and high gradient peaks of variable amplitude and/or inter-peak duration and a second modulated portion of relatively low current and low gradient which is substantially without modulated peaks. The spark is preferably generated from two or more programmable current sources. The invention also provides an optical emission spectrometer comprising the spark generator and a method of optical emission spectroscopy using the spark generator.

Abstract: The invention provides a method of performing X-ray diffraction (XRD) and/or X-ray fluorescence (XRF) analysis of a sample, comprising: irradiating a sample with X-rays from an X-ray source; providing a combined XRD and XRF detection arrangement comprising a scanning wavelength selector and at least one X-ray detector for detecting X-rays selected by the wavelength selector; and performing XRD analysis of the sample by selecting at least one fixed wavelength of X-rays diffracted by the sample using the scanning wavelength selector and detecting X-rays of the selected fixed wavelength(s) at one or more values of the diffraction angle cp at the sample using the X-ray detector(s); and/or performing XRF analysis of the sample by scanning wavelengths of X-rays emitted by the sample using the scanning wavelength selector and detecting X-rays of the scanned wavelengths using the X-ray detector(s).