Single-shot high-fidelity large-sequence chirped spectral-mapping ultrafast photography

Single-shot ultrafast optical imaging enables the visualization of dynamic scenes at ultrahigh temporal resolution, serving as an indispensable tool for studying nonrepeatable ultrafast phenomena. By employing a time-wavelength mapping within an illumination pulse or pulse train, wavelength-multiplexing ultrafast optical imaging has played a crucial role in observing the ultrafast interactions between laser and materials. However, achieving single-shot wavelength-multiplexing ultrafast imaging with large sequences and high fidelity remains a significant challenge due to spatiotemporal multiplexing in detection. This limitation hinders the accurate analysis of ultrafast phenomena. Here, we report a demosaicing algorithm-based chirped spectral-mapping ultrafast photography, termed DMA-CSMUP, which enables ultrafast imaging with high fidelity and large sequences. DMA-CSMUP can capture up to 42 sequential images in a single shot by combining multiple spectral bands with different hyperspectral cameras. Meanwhile, a joint demosaicing and denoising algorithm is developed to enhance image fidelity significantly and avoid pixel loss caused by mosaic filter arrays. The powerful detection capability of DMA-CSMUP is verified experimentally by imaging the plasma generation and shockwave expansion in glass, as well as the ablation dynamics on a silicon surface induced by a femtosecond laser pulse. DMA-CSMUP provides a well-established tool for observing ultrafast dynamics with high-resolution temporal and spatial information, which is anticipated to facilitate the research of various ultrafast phenomena.