Conventional Raman methods rely specifically on data collected from back-scattering, which limits analysis of samples such as tablets and capsules to their surfaces. The surface is often not representative of the bulk in a tablet or capsule – even without coatings or capsule shells in the way.

Transmission Raman Spectroscopy probes the entire content through ≥10 mm of sample. The TRS method works by illuminating the sample on one side and collecting the transmitted light on the other. The resulting transmission Raman spectrum is highly representative of the entire sample mixture, enabling sensitive, accurate, and fast quantitative measurement of the whole object in one quick measurement.

Unlike other spectroscopic methods, such as Near-Infrared, TRS is typically insensitive to tablet coatings and capsule shells, so no sample preparation is required. TRS is also insensitive to typical variations in particle size, sample compaction and moisture.