Towards a spectrometer calibration protocol for CARS, SRS and SR data

Figure 1: Correction workflows for CARS, SRS, and SR spectra. The correction sequence for SR data can be performed according to ref Bocklitz et al [1].
For the comparison of spontaneous Raman spectra (SR) and coherent Raman spectra (CRS), such as coherent anti-Stokes Raman spectra (CARS) and stimulated Raman spectra (SRS), complex preprocessing, calibration and standardization workflows are needed. The modeling of the Raman based measurement processes will allow the construction of these correction procedures (or the respective sequence of methods).

Additionally, an understanding of the sources of the signal differences between SR, SRS, and CARS will be gained.

As the measurement of CARS, SRS and SR are performed in different wavelength, absolute wavenumber and energy ranges a detailed understanding of the influence of these wavelength ranges on the measured signal is needed. Therefore, we started the modeling with a protocol for a correction of Raman spectra different recorded with different wavelength [1]. The SRS and CARS modeling and correction is ongoing.

  1. Bocklitz TW, Dörfer T, Heinke R, Schmitt M, Popp J. Spectrometer calibration protocol for Raman spectra recorded with different excitation wavelengths. Spectrochimica acta. Part A, Molecular and Biomolecular Spectroscopy. 2015 ;149:544-549. DOI: 10.1016/j.saa.2015.04.079. PMID: 25978023.