Measurement Methods for Atomic Fluorescence and Laser-Enhanced Ionization Spectrometries with a Copper-Vapor Pumped Dye Laser

Abstract

Several correction methods for several types of spectral and electrical interferences with a copper-vapor pumped dye laser system are presented. A tunable pulsed dye laser pumped with a copper vapor laser was used to excite the atomic fluorescence of Li, Na, In, and Fe and the atomic ionization of Li, In, and Fe. Correction methods used involved either modulation of the pulsed laser output and subsequent subtraction of noise or electrical bandwidth limitation of the signals to enhance the signal to high-frequency laser noise ratio. These methods are shown to provide a significant reduction in high-frequency interference, a major noise source with this type of pump laser. These three correction methods are shown to provide a significant improvement in the detection power of both laser-enhanced ionization and fluorescence methods. Limits of detection are presented for each correction method.