Coherent anti-Stokes Raman scattering microscopy based on spectral encoding

Abstract

We present a theoretical description of spectrally encoded coherent anti-Stokes Raman scattering (SE-CARS) microscopy. Conceptually, two broadband laser beams, whose center frequencies differ by the Raman shift of the sample to be measured, are diffracted with equal dispersions by a single grating and form a focal line on the sample plane. The CARS signal is generated in such a way that its spectral profile reflects the spatial distribution of sample molecules with the same vibrational frequencies. The spectral point spread functions for a Raman shift of 2850cm−1 are calculated to estimate the number of resolvable points.