Atmospheric gas monitoring using tuneable diode laser absorption spectroscopy

Atmospheric gas monitoring using tuneable diode laser absorption spectroscopy 

Since its first inception, absorption spectroscopy exploiting wavelengths in the mid-IR has evolved to become a powerful analytical tool in many scientific and technical applications. However, the majority of commercially available lasers exhibit emission wavelengths in the UV, visible and near-IR ranges, but much less so in the mid-IR. 

All organic compounds, and many inorganic compounds, exhibit strong absorption in the mid-IR spectral region (2.5-15 pm see Figme 28.1) due to resonance with the rotation-vibrational modes of the 

The problem of unwieldy lead-salt lasers is now diminishing, with the rapid advance of room-temperature near-IR lasers (emerging Irom telecommunication laser technology), and even more so with the advent of the the quantum cascade laser (QCL). 

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