Optimization of Pulsing Conditions for Hollow Cathode Lamps for Atomic Fluorescence Spectrometry

Abstract

The effect of pulsing conditions on hollow cathode lamp output, on the intensity of atomic fluorescence excited, and on atomic fluorescence detection limits has been examined for a number of commercial sealed lamps. Optimization must be carried out on an individual lamp basis. Maximum integrated intensity is obtained by minimizing the dc current through the lamp and making the duty factor as large as possible within the limit set by the maximum allowed average current through the lamp. Integrated intensity is largely independent of pulse width and depends only to a small extent on peak current. For the range of operating conditions considered in this study, the effect on atomic fluorescence of line broadening due to pulsing at high peak currents was small.