Spectrally-broad coherent anti-Stokes Raman scattering hyper-microscopy utilizing a Stokes supercontinuum pumped at 800 nm.

We demonstrate spectral-focusing based coherent anti-Stokes Raman scattering (SF-CARS) hyper-microscopy capable of probing vibrational frequencies from 630 cm-1 to 3250 cm-1 using a single Ti:Sapphire femtosecond laser operating at 800 nm, and a commercially-available supercontinuum-generating fibre module. A broad Stokes supercontinuum with significant spectral power at wavelengths between 800 nm and 940 nm is generated by power tuning the fibre module using atypically long and/or chirped ~200 fs pump pulses, allowing convenient access to lower vibrational frequencies in the fingerprint spectral region. This work significantly reduces the instrumental and technical requirements for multimodal CARS microscopy, while expanding the spectral capabilities of an established approach to SF-CARS.