Sensing system for multiple measurements of trace elements using laser-induced breakdown spectroscopy

The setup, micro-droplet sampling system combined with a gas-flow system for measurement using laser-induced breakdown spectroscopy (LIBS) is introduced. This setup was designed for high sensitive quantitative analysis using ink-jet technology and gas-flow assistance. The setup presented here allowed precise detection of a uniform volume of 30-μm micro-droplet location for guiding it into a 53.2-μm beam spot area, under the effects of any ambient gas. In this paper, experimental results with the use of two kind of ambient gasses; air and argon gas, were compared in order to find proper time-delay values for time-resolving spectroscopy. From time-gated spectroscopy analysis of these experiments, different relaxation time spectral data were obtained. This result indicates that in the case of using argon ambient for assistance, broader range of time-gate setting is required as compared with the case of using air ambient. Sensitive LIBS measurement for trace elements was shown by using the proper gate-setting value. © 2009 The Institute of Electrical Engineers of Japan.