Coherent Raman scattering (CRS) microscopy, while powerful for biomedical applications, has been hindered by limitations of traditional solid-state lasers. This paper presents a high-power self-synchronized two-colour pulsed fibre laser overcoming these shortcomings. The laser achieves significant improvements in intensity stability, timing jitter, average power fluctuation, modulation depth, and pulse width variation. This allows for high-contrast, fast CRS imaging without complex noise reduction techniques, demonstrated through imaging of various biological samples, including living human cells and mouse tissues. Multimodal nonlinear imaging capabilities are also showcased. The design offers a general approach for modifying existing lasers into synchronized two-colour lasers, promoting wider CRS applications.

Cihang Kong, Christian Pilger, Henning Hachmeister, Xiaoming Wei, Tom H. Cheung, Cora S. W. Lai, Nikki P. Lee, Kevin K. Tsia, Kenneth K. Y. Wong, Thomas Huser