Microspectroscopy sampling depth

A third class of sampling geometries involves Raman microscopy and closely related Raman imaging techniques. Combination of a Raman spectrometer with a modified optical microscope permits spectra to be obtained from very small sample regions, down to less than 1 pm laterally and a few microns in depth (Fig. 6.3). Raman microspectroscopy is a term generally used to describe this spatially resolved technique in which spectra are obtained... 

Several modes of operation are available in state-of-the-art confocal Raman microspectroscopy, including the measurement of samples with a spatial resolution of less than 1 pm, depth profiling, and line mapping. LaPlant and Ben-Amotz have given a detailed description of the design and construction of a confocal Raman microspectrometer [34] and a number of instruments are available commercially. 

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