A Laser Microprobe System for Controlled Atmosphere Time and Spatially Resolved Fluorescence Studies of Analytical Laser Plumes

Abstract

A laser microprobe system has been developed that provides for time and spatially resolved studies of the interaction between the material ejected by a laser from a sample surface and the gaseous species in a controlled-atmosphere chamber. A microsecond flashlamp pumped dye laser atomizes the sample, and a narrow band, accurately tunable flashlamp pumped dye laser is the light source for absorption and fluorescence measurements of atomic and molecular species. A sample wheel rotates and translates to provide a new surface for hundreds of shots before resurfacing is required. Stepper motors allow the laser plume to be positioned in three dimensions by manual or computer control. Examples are given of the types of measurements that are possible under computer control. In an observation region comprising 0.05% of the plume, 109 atoms of Li are detectable.