Tunable Infrared Laser Sources: From Laboratory into Space

The development of promising new gas sensors based on diode and quantum cascade lasers and some of their environmental and industrial applications to trace species detection in the Earth’s atmosphere will be discussed. Ultra-sensitive, highly selective and real-time concen-tration measurements of many trace gases in the mid-infrared spectral region, where most mole-cules possess characteristic absorption spectra, have been demonstrated. Some of the recent advances in photonics and computer technology have been employed in various compact gas sensor architectures to achieve minimum detec-table concentrations down to the parts per billion level. Real world applications of these sensors can range from chemical analysis to assessing the air quality in spacecraft habitats and the presence of CO₂ and water vapor on Mars in 2003.