Coupling of fibre-optics to reacting systems

Remote visible and ultraviolet absorption and emission spectroscopy 

This analysis would predict that the reflection coefficient, R, would decrease with cure, since 2 will progressively increase, whereas R was found to increase systematically and produce a profile that followed that of a DSC conversion-time curve for an epoxy resin. 

This suggests that the process of energy transfer to the fibre is more complex and that changes to the NA of the fibre may be important. 

Raman spectroscopy lends itself to remote monitoring of reactive processing using optical fibres because the excitation and scattered mdiation will be in the visible or NIR spectral regions and thus with in the bandwidth of quartz fibres. Thus all the principles described earlier in Section 3.4.2 apply. It was initially believed that remote Raman spectroscopy was limited in application (Harmer and Scheggi, 1989) because of 

At about the same time as these concerns were expressed, the optimization of an optical-fibre system for use in remote Raman spectroscopy was described (Hendra et al, 1988). The areas explored are similar to those for remote emission spectroscopy discussed earlier in Section 3.4.2, and techniques for achieving the efficient transfer of the weak scattered radiation to the gathering probe include the use of 

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