Wavelength Modulation Spectroscopy of Oxygen A Band Transitions for Non-Intrusive Concentration Measurements

Abstract

The technique of Frequency Modulation (FM) and Wavelength Modulation Spectroscopy has been used [1] very successfully recently to perform several different types of measurements, with the applications of this technique growing as advances in semiconductor technology result in the availability of reliable, tunable single-mode semiconductor diode lasers in parts of the electromagnetic spectrum which were previously inaccessible this way.