A CONCEPT FOR OPEN-PATH AIR-POLLUTION MONITORING

This monitoring concept combines an acousto-optic tunable fitter for e mission spectroscopy (3.5 to 14 mum) with a mid-IR (4.6 to 5.4 mum) an d a far-IR laser (9.2 to 10.9 mum) for absorption spectroscopy in an i nstrument for the optical remote measurement of ppb-ppm concentration of air pollutants. It utilizes commercially available components, is f ast (approximately 2 minutes for 120 gases), covers a large area (appr oximately 6 km path lengths), measures the distance to any reflecting object and takes measurements along any line-of-sight.