Application Note: CARS Microscopy

In the last ten years multi-photon-microscopy has become increasingly popular to enhancing contrast and resolution for modern microscopic imaging due to the utilization of non-linear optical effects. Amongst many methods of multi-photon-microscopy, two-photon-excitation fluorescence- microscopy is the most popular one with more than a few hundred systems installed every year. The big draw back of two-photon-fluorescence microscopy, however, is the use of dyes for creating the images. Methods to overcome the problems connected with dyes are based on non-linear optical effects such as second and third harmonic generation (SHG, THG), Raman scattering or Coherent Antistokes Raman Scattering (CARS), a third order non-linear process (X(3) process) involving four photons.