A simplified theoretical analysis of the S/N performance of Fourier transform (FT) Raman spectrometers compared with conventional scanning machines is presented. Calculations indicate that the multiplex gain may be significantly degraded due to the shot noise from the Raman signal, and this situation is exacerbated when Rayleigh radiation reaches the detector. It is expected that use of detectors with a noise equivalent power of 10−15 W would largely eliminate any multiplex gain in FT-Raman spectroscopy.
N. J. Everall and J. Howard, "Signal-to-Noise Considerations in FT-Raman Spectroscopy," Appl. Spectrosc. 43, 778-781 (1989)