Gas detection by correlation spectroscopy employing a multimode diode laser

作者:Lou Xiutao; Somesfalean Gabriel; Zhang Zhiguo*
来源:Applied Optics, 2008, 47(13): 2392-2398.
DOI:10.1364/AO.47.002392

摘要

A gas sensor based on the gas-correlation technique has been developed using a multimode diode laser (MDL) in a dual-beam detection scheme. Measurement of CO2 mixed with CO as an interfering gas is successfully demonstrated using a 1570 run tunable MDL. Despite overlapping absorption spectra and occasional mode hops, the interfering signals can be effectively excluded by a statistical procedure including correlation analysis and outlier identification. The gas concentration is retrieved from several pair-correlated signals by a linear-regression scheme, yielding a reliable and accurate measurement. This demonstrates the utility of the unsophisticated MDLs as novel light sources for gas detection applications.