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- Zeitschriftenartikel (2) (entfernen)
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- Spatial heterodyne spectroscopy (2) (entfernen)
Organisationseinheit der BAM
Die räumlich aufgelöste Heterodyn-Spektroskopie (SHS) kombiniert dispersive und interferometrische Techniken zur Gewinnung spektroskopischer Informationen und kann in einem anpassbaren Instrument realisiert werden. SHS wird für die chemische Analyse von verschiedenen Materialien mit Hilfe der Laser-induzierten Plasmaspektroskopie (LIBS) und der Raman-Spektroskopie eingesetzt.
A spatial heterodyne spectrometer (SHS) is tested for the first time in combination with laser-induced breakdown spectroscopy (LIBS). The spectrometer is a modified version of the Michelson interferometer in which mirrors are replaced by diffraction gratings. The SHS contains no moving parts and the gratings are fixed at equal distances from the beam splitter. The main advantage is high throughput, about 200 times higher than that of dispersive spectrometers used in LIBS. This makes LIBS-SHS a promising technique for low-light standoff applications. The output signal of the SHS is an interferogram that is Fourier-transformed to retrieve the original plasma spectrum. In this proof-of-principle study, we investigate the potential of LIBS-SHS for material classification and quantitative analysis. Brass standards with broadly varying concentrations of Cu and Zn were tested. Classification via principal component analysis (PCA) shows distinct groupings of materials according to their origin. The quantification via partial least squares regression (PLS) shows good precision (relative standard deviation , 10%) and accuracy (within 6 5% of nominal concentrations). It is possible that LIBS-SHS can be developed into a portable, inexpensive, rugged instrument for field applications.