Non-scanning CARS microscopy using wide-field geometry

We report a wide-field Coherent Anti-Stokes Raman Scattering (CARS) microscopy technique based on non-phasematching illumination and imaging systems. This technique is based on a non-collinear sample illumination by broad laser beams and recording image of sample at anti-Stokes wavelength using full-frame image detector. An amplified Ti:Sapphire laser and an Optical Parametric Amplifier (OPA) provided picosecond pump and Stokes beams with energies sufficient for CARS generation in an area of 100 μm in diameter. The whole field of view of the microscope was illuminated simultaneously by the pump and Stokes beams, and CARS signal was recorded onto a cooled CCD, with resolution determined by the microscope objective. Several illumination schemes and several types of thin sample preparations have been explored. We demonstrated that CARS image of a 100x100 μm sample can be recorded with submicrometer spatial resolution using just a few laser pulses of microJoule energies.