Monochromators:

The fluorescence emission from the excited atomic species is commonly dispersed through monochromators.  As you know, the monochromators are devices in which select a given emission line and isolate it from other lines because of molecular band emissions and all nonabsorbed lines. Most commercial instruments use diffraction gratings for the reasons. These grating instruments could manage a high resolution over a range of wavelengths. Within laser induced ionisation spectrometry no spectral isolation is needs at all. Within some cases, the detection could be performed without requires for spectral dispersion, e.g., through using only filters.