Evanescent wave Raman spectroscopy with

Raman Spectroscopy with the Evanescent Wave - Experiments... 

Figure 10. Experimental set-up for Raman spectroscopy with the evanescent wave. For excitation, an argon ion laser was used ( 488 nm, output power 1.5 W cw). The material of the reflection plate is fused silica or super dense flint glass. Monochromator Ebert mount Jarrell-Ash 30 cm focal length diffraction gratings 150 or 600 g/mm.

This article shows how the evanescent wave can be used with advantage for spectroscopic purposes in the field of biomedical engineering. Three types of spectroscopy can be done with the evanescent wave in the UV-VIS range of the spectrum (a) attenuated total reflection (ATR) spectroscopy, which is well known in the infrared (b) the excitation of Raman scattering with the evanescent wave and (c) the excitation of fluorescence with the evanescent wave. The first two types will be discussed in this article the third is discussed for example by Hirschfeld U) and more recently by Watkins and Robertson (2). But before going into details a historical review may be of some interest. 

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