Laser-induced shock wave plasma spectrometry using a small chamber designed for in situ analysis

Direct spectrochemical analyses on large bulk samples such as metal plates have been performed by using a small vacuum chamber, which was attached dir ectly to the sample surface through ano-ring. This technique allowed the in situ generation of laser plasma and hence overcome to a good extent the in convenient and sometime clumsy sample preparation procedure required in Las er-Induced Shock Wave Plasma Spectrometry. Additionally, the presence of th e o-ring near the target surface effectively shielded off the surrounding a rea from the undesirable continuum emission from the primary plasma, and th ereby enhanced the detection sensitivity of this technique. Using zinc plat e and Pb glass as samples, it was further demonstrated in this experiment t hat even the time-integrated spectra, obtained by employing an OMA system, still exhibited a lower background than those obtained by ordinary time-res olved Laser-Induced Breakdown Spectroscopy. (C) 2000 Elsevier Science B.V. All rights reserved.