Laser spectrometers for atmospheric analysis

This chapter will deal with practical application a practical applications of spectroscopy techniques. We can speak of a practical application when a scientific discovery has been found suitable to carry out a specific task, either better, or at a lower cost (or both) than existing devices.Since many years [1-4] absorption spectroscopy has proven to be a powerful tool for themeasurement of the concentrations of gaseous species. Yet, nowadays only very few peoplehave seen commercial gas analyzers at work.This means that either the principle of the technique is not good, or that the technologicaldevelopment is insufficient, or the benefit/cost ratio is lower than that of already existingFour methods will be described. For each of them the advantages and drawbacks will behighlighted, in order to understand for which kind of measurement they are most suitable. Thefour methods are Mass Spectrometry, Gas Chromatography, Chemical Methods and Solid StateSensors. The available space is not sufficient to enter all details of the described techniques anddevices. To overcome this, an extensive bibliography will be provided.