A SELF-CALIBRATION APPROACH FOR TUNABLE LASER SPECTRAL ABSORPTION SENSORS

摘要

An on-line self-calibrating system where prior calibration information is updated by combining prior stored calibration information with current sensor reading information to simulate the introduction of a known calibrating sample and to generate new calibration information. A preferred embodiment of the present invention is in a laser spectral absorption system for determining the concentration of a particular gas in a gaseous sample by sensing a characteristic narrow spectral pulse in the absorption characteristics of the sample, the area or spectral integration of the pulse being proportional to the concentration of the particular gas. The disclosed technique effects on-line recalibration of the system based on current operating parameters of the system to compensate for time or usage induced degradation in system accuracy without introducing a sample of a known concentration of the gas into the system.