Evaluation of a nanosecond dissipative soliton resonance fiber laser for multiphoton microscopy.

Multiphoton microscopy often relies on femtosecond lasers due to their high peak powers and short pulse durations. However, these systems (e.g., Ti:Sapphire) are expensive, complex, and require dispersion compensation to maintain pulse parameters in the sample plane. Nanosecond sources, such as dissipative soliton resonance (DSR) lasers, offer a compact, low-cost, fully fiber-based alternative that eliminates the need for dispersion management due to their longer pulse durations. Here, we demonstrate the use of a DSR laser for multiphoton imaging. The system delivers 1064 nm nanosecond pulses at a 2 MHz repetition rate. We show that high-quality images can be obtained using a non-complex laser source by optimizing the peak and average power of the DSR laser pulses. Comparative experiments with a femtosecond laser demonstrate that similar fluorescence levels can be achieved from the same sample, while also highlighting the strong impact of dispersion on femtosecond pulses compared to the robustness of nanosecond pulses. We present the first demonstration of the application of a DSR laser in multiphoton microscopy, showing that it is a viable alternative for more complex sources, expanding access to the technique in less demanding environments.