Multi-focus excitation coherent anti-Stokes Raman scattering (CARS) microscopy and its applications for real-time imaging

We developed a multi-focus excitation coherent anti-Stokes Raman scattering (CARS) microscope using a microlens array scanner for real-time molecular imaging. Parallel exposure of a specimen with light from two highly controlled picosecond mode-locked lasers (jitter of 30 fs through an electronic low-pass filter with 150 Hz bandwidth, point-by-point wavelength scan within 300 ms) and parallel detection with an image sensor enabled real-time imaging. We demonstrated real-time CARS imaging of polystyrene beads (frame rate of 30 fps), a giant multi-lamellar vesicle of dipalmitoylphosphatidylcholine (frame rate of 10 fps), and living HeLa cells (frame rate of 10 fps).