A MODEL FOR OPTICAL SATURATION THERMAL LENS SPECTROMETRY

A model for thermal lens spectrometry (TLS) in partial optical saturation conditions is developed. The model predicts that optical saturation is approached to a significant degree in many TLS experiments, and that it can be reached to a high degree with the currently available laser and optical technologies. When optical saturation is approached, the sensitivity decreases and the signal depends on the rate constant of the slowest step of the decay process. Important consequences for the future development of photothermal spectrometric techniques can be derived.