12 Optical spectroscopy related to analytical techniques have attracted much interest in recent years and became a central part of versatile instruments used for trace gas monitoring. Optical methods are based on different interactions between radiation and matter (absorption, emission and scattering) and use different sources of radiation such as conventional lamps, lasers, the sun, etc. Differential Optical Absorption Spectroscopy is a good example of these kind of techniques where commercial instruments are available today. Typically, it consists of a collimated broadband radiation source that shines a beam of light through an open atmospheric path several hundred meters long; at the other end, a receiving telescope is located which focus the beam on a medium resolution spectrometer-photodetector system that analyzes the wavelength spectrum of the incoming light within a certain range. The absorption bands of a specific gas component failing in this range are thus detected. For multicomponent analysis, the spectrometer must be scanned across different wavelength ranges introducing potential error sources.

Date Published: 14 February 2001
PDF: 9 pages
Proc. SPIE 4199, Water, Ground, and Air Pollution Monitoring and Remediation, (14 February 2001);

Published in SPIE Proceedings Vol. 4199:
Water, Ground, and Air Pollution Monitoring and Remediation
Tuan Vo-Dinh; Robert L. Spellicy, Editor(s)