Grating throughput

TR measurements for correspondingly increased rejection of Rayleigh scattering. The addition of each grating typically introduces a throughput efficiency factor of roughly 30%, however, so that the overall efficiency of a... 

The second fundamental advantage of an FT spectrometer over a grating spectrometer is often called Jacquinot s advantage and derives from the increased optical throughput of an interferometer compared to a grating monochrometer. 

This fact puts the interferometer at a disadvantage compared with a dispersive spectrometer for which the gratings can be changed during measurement to allow increased throughput and efficiency for longer wavelength radiation. 

The tail of the plasma formed at the tip of the torch is the spectroscopic source, where the analyte atoms and their ions are thermally ionized and produce emission spectra. The spectra of various elements are detected either sequentially or simultaneously. The optical system of a sequential instrument consists of a single grating spectrometer with a scanning monochromator that provides the sequential detection of the emission spectra lines. Simultaneous optical systems use multichannel detectors and diode arrays that allow the monitoring of multiple emission lines. Sequential instruments have a greater wavelength selection, while simultaneous ones have a better sample throughput. The intensities of each element s characteristic spectral lines, which are proportional to the number of element s atoms, are recorded, and the concentrations are calculated with reference to a calibration standard. 

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