A TDLS analyzer is a gas analyzer that uses Tunable Diode Laser Absorption Spectroscopy to measure the concentration of a specific gas by detecting how that gas absorbs laser light at a selected wavelength. It is commonly used for continuous, real-time monitoring of gases such as NH₃, HCl, HF, CH₄, CO, CO₂, O₂, and H₂O in industrial process control and environmental emission monitoring.ESEGAS TDL laser gas analyzers are based on TDLAS technology and are designed for rapid, non-contact, continuous online measurement of target gases.