Glow discharge optical emission spectrometer (1984)

In this apparatus, a plasma erodes the surface of a solid sample and simultaneously excites the eroded species, allowing the chemical concentration of the elements to be determined as a function of depth. The first radio frequency sources for this device, which extended the scope beyond the metallurgy sector, was developed in collaboration with Ken Marcus of Clemson University in South Carolina, USA and Richard Passetemps of the state-owned Renault company.