4. Applications

Optical emission spectrometry (OES) in the visible and ultraviolet ranges has a very broad field of application, both in terms of the elements that can be analyzed and the variety of metallic matrices involved. Elements analyzable by OES represent 80% of the periodic table. Halogens with excitation and ionization energies above 15 eV are not measured. Other elements, such as arsenic and tellurium, have very moderate detection limits (50 to 100 ppm). Analysis of N ₂ and O ₂ gases requires extensive vacuums and high-performance optics. At 149.2 nm, atomic nitrogen is dosable above 20 ppm on some instruments. Oxygen becomes accessible at 130.3 nm at higher levels (from 20 to 30 ppm).

The high sensitivity of spark-source SEO limits the range of measurable concentrations for...