Many Raman instruments today operate under computer control. All such instruments are capable of subtracting one spectrum from another, and thus, these have the capacity for RDS studies. The subtraction of solvent bands, the determination of polarization components, and other computations which do not require extremely accurate frequency matching for the two (or more) samples are thus readily achieved. The use of rotating liquid cells, rotating powder holders, a rotating lens systems, and/or various rotating polarization devices coupled to a photodiode based triggering device does allow RDS spectra with great frequency accuracy of virtually any kind of sample to be recorded.
