Stimulated Raman scattering (SRS) microscopy is a powerful tool for chemically-sensitive non-invasive optical imaging.
However, the short-pulse laser sources, which are currently being employed for this imaging technique, are still
expensive and require substantial maintenance to provide temporal and spectral overlap. SRS imaging, which utilizes cw
laser sources, has a major advantage over pulsed lasers, as it eliminates the possibility of cell damage due to exposure to
high-intensity light radiation, while substantially reducing the cost and complexity of the set-up and keeping a sub-cellular
spatial resolution. As a proof-of-principle, we demonstrate microscopic imaging of dimethyl sulfoxide using two
independent, commonly used and inexpensive lasers: a diode-pumped, intracavity doubled 532 nm laser and a He-Ne
laser operating at 633 nm. In our proof-of-principle experience, dimethyl sulfoxide acts as a contrast agent providing
Raman scattering signal. The 532 nm and 633 nm lasers act as excitation and probe sources, respectively .