Segmentation integration in multivariate curve resolution applied to coherent anti-Stokes Raman scattering

Coherent anti-Stokes Raman scattering (CARS) is a vibrational spectroscopy method based on a coherent χ (3) nonlinear interaction between light and matter through four-wave mixing. CARS process has been extensively used as a microscopy technique in biology. However the shape of CARS spectra is generally complex because of the combination of both resonant and non-resonant contributions, which limits the development of CARS microspectroscopy applications. In this context, phase retrieval methods (PRM) like the maximum entropy method (MEM) [1] are commonly used to extract the vibrationally resonant signal, corresponding to Im[χ (3) ], and thus to provide Raman-like spectra, which are more suitable for interpretation.