Limited Absorption and Fluorescence Spectroscopy with Lasers

After the discussion of the Doppler-limited spectroscopy . Chap.10 gives an extensive treatment of various techniques which allow sub-Doppler spectroscopy.  

In classical absorption spectroscopy, radiation sources with a broad emission continuum are preferred (e.g., high-pressure Hg arcs, Xe flash lamps, etc.). The radiation is collimated by a lens and passes through the absorption cell. Behind a dispersing instrument for wavelength selection (spectrometer or interferometer) the intensity Ij(x) of the transmitted light is measured as a function of the wavelength x (Fig.8.la). By comparison with a 

The spectral veeolution is generally limited by the resolving power of the 

Contrary to radiation sources with broad emission continua used in conventional spectroscopy, tunable lasers offer radiation sources in the spectral range from the uv to the ir with extremely narrow bandwidths and with spectral power densities which may exceed those of incoherent light sources by many orders of magnitude (see Chap.7). 

In several regards laser absorption spectroscopy corresponds to microwave spectroscopy where clystrons or carcinotrons instead of lasers represent tun- 

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Doppler-Limited Absorption and Fluorescence Spectroscopy with Lasers... 

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