Near-Infrared Raman Spectroscopy with a Scanning Spectrometer

Abstract

This article shows that, by means of a conventional Raman spectrometer which has been carefully designed for near-IR Raman excitation, results can be obtained that are similar to those achieved with Fourier transform Raman instrumentation. We demonstrate the performance of such an apparatus on a variety of samples including examples of gaseous samples. As far as we know, up to now, no Raman spectra of gases have been published for excitation at 1064 nm. From a comparison of gas spectra excited at 1064 nm and 514 nm, we estimate the sensitivity of our apparatus to be at least three orders of magnitude lower than that for excitation in the green spectral region. Nevertheless, the main features in Raman spectra of gases can be recorded. High-performance solid-state spectra are compared with spectra recorded by means of FT techniques. They show superior sensitivity in the low-frequency range.

Raman Spectroscopy

“…There is currently a disagreement as to whether this is best achieved using FT systems or traditional dispersive instrumentation, and the debate tends to be highly subjective in its nature. A useful paper has appeared which addresses for the first time the consequences of the Fourier transform in FT Raman spectroscopy and highlights its advantages and disadvantages (51) and other papers consider the relative merits of the two approaches (52)(53)(54)(55). The FT technique has been separately reviewed (56,57).…”

Correcting transmission losses in short-wave infrared spatially offset Raman spectroscopy measurements to enable reduced fluorescence through-barrier detection

“…The effects of points 1 and 2 on the SORS signal strength are well characterised and understood from previous work, including extensive literature on CR at 1064 nm generated during the evolution of FT-Raman instrumentation. [31][32][33][34] In contrast, point 3 is less well understood. In order to enhance this understanding, the transmission properties of a wide range of container materials (including plastics, glass, paper and fabrics) have been characterised here.…”