Current Status of Calibration-Free Tunable Diode Laser Spectroscopy Techniques for Industrial Gas Monitoring

Industrial gas monitoring applications have greatly benefited from recent developments in tunable diode laser spectroscopy which is the industry standard in non-invasive, real-time measurement. Calibration-free wavelength modulation spectroscopy (WMS) techniques have obviated the need for signal calibration. This paper presents a comparison of some of the significant recent developments in this field.