<i>In-situ</i> real-time monitoring of ultrafast laser processing using wide-field high-resolution snapshot compressive microscopy

Over the last decades, ultrafast laser processing has become a widely used tool for manufacturing of micro-and nanostructure.Real time monitoring of laser material processing opens opportunities to inspect the process and provide feedback.To date, in-situ and real-time monitoring of laser material processing is rarely performed.Towards this end, in this paper, we propose a dual-path snapshot compressive microscopy (DP-SCM) for highspeed, large field-of-view and high-resolution imaging for in-situ and real-time ultrafast laser processing.In the evaluation of DP-SCM, the field-of-view, lateral resolution and imaging speed are measured to be 2 mm, 775 nm and 500 fps respectively.In ultrafast laser processing, the laser scanning process is observed by DP-SCM system when translating the sample stage and scanning the focused femtosecond laser respectively.Finally, we have monitored the development of self-organized nano-gratings structure, validating our system's potential to unveil new material mechanisms.The proposed method serves as an add-up (plug-and-play) module to any imaging setup and has vast potential in opening up new avenues for high-throughput imaging in laser material processing.