Figure 1. Schematic diagram of the Coherent Anti-Stokes Raman Scattering (CARS)/Two-Photon Autofluorescence (TPAF) microscope. The system consists of a Nd:Vanadate picosceond laser and an optical parametric oscillator. The scanning microscope is based on the Olympus FV-1000 confocal microscope system with two non-descanned external detectors in the epi-direction. EM1 is an emission filter to detect the CARS signal at 662 nm by the CARS PMT detector and EM2 is an emission filter to allow TPAF signal from 420 to 520 nm to be detected by the TPAF photomultiplier tube (PMT).