Multichannel-coupled compressed ultrafast photography

Compressed ultrafast photography (CUP) is currently the fastest receive-only ultrafast imaging technique with snapshot. CUP can capture non-repetitive transient events through three-dimensional (3D) image reconstruction based on a compressed sensing (CS) algorithm. However, CUP is a lossy imaging technique via image encoding and decoding, so how to further improve the image reconstruction accuracy has always been a goal pursued by scientists. Here, we develop a novel design of multichannel-coupled CUP (i.e. MC-CUP) to improve the image reconstruction accuracy. MC-CUP can not only increase the sampling rate, but also keep the snapshot of CUP. To demonstrate the advantage of MC-CUP in the image reconstruction accuracy, we measure a spatially modulated picosecond laser pulse and a 3D stepped structure, and these experimental results confirm that MC-CUP can significantly improve the spatial and temporal resolutions compared to CUP. This study will further promote the practical applications of CUP in ultrafast imaging, especially for biomedical imaging with high spatial resolution.