Dual-laser CCD-Raman spectrometer applied to on-line measurement of paper coating paste

A dual-laser Raman spectrometer was developed, in which the two lasers image two different parts of the spectrum alternately on the same spectrograph. This solves the resolution/bandwidth trade-off problem of CCD Raman spectrometers, previously solved with a dual-grating technique. The dual-laser technique has, however, an additional advantage of alleviating the contradiction between sample fluorescence and detector response, which is illustrated here by applying the technique to the measurement of paper coating paste.