Remote spectroscopic analysis of ppm‐level air pollutants by Raman spectroscopy

The design and performance of a remote Raman spectrometer are described. The unit has been tested at ranges from several hundred yards to a half‐mile in full daylight under both clear atmosphere and fog conditions. Good S/N ratios were obtained for the detection of atmospheric H2O and CO2 as well as SO2 (300 ppm m) and hydrocarbon vapors (17 ppm m) in controlled sources, with a range resolution of 10 m. This is more than two orders of magnitude better than the best published results to date.