FT-Raman Spectrometers with Near-Infrared Excitation

FT-Raman Spectrometers with Near-Infrared Excitation 

Interferometers are superior to monochromators for obtaining spectra of electromagnetic radiation, but technical problems prevent interferometers from being used in routine spectrometers at wavelengths shorter than the near-infrared. Fortunately, Raman excitation by near-infrared radiation is just possible law, cf. Section 3.3 of Chapter 3). 

The laser in FT-Raman spectrometers (Fig. 4.5) is the continuous wave Nd /YAG system operating at 1064 nm with output power up to 2000 mW. The laser is optically pumped by either a lamp or diode system. In both cases, nonlasing hnes are generated. They have to be removed by very effective notch filters (NF), otherwise they get mixed up with the Raman spectrum producing so-called laser line artifacts. 

Raman Crating Polychromator with Muitichannei Detector 

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FT-Raman spectrometer with near infrared excitation... 

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