Abstract

Atomic absorption spectroscopy has traditionally been used to give moderately sensitive detection of trace atomic species aspirated from a test solution into a flame. Laser absorption methods have recently been used to detect major molecular species such as OH radicals.¹ Such methods generally require a minimum of 5-10% absorption. We report here on the application of frequency modulation (FM) spectroscopy² to improve significantly the sensitivity of laser absorption measurements in a flame environment.

© 1983 Optical Society of America