Real-time imaging of countless femtosecond dynamics necessitates extreme speeds far exceeding the capabilities of electronic sensors. This paper introduces Compressed Ultrafast Spectral Photography (CUSP), a technique achieving 70 trillion frames per second (Tfps) and 1000 frames simultaneously in active mode, and 4D spectral imaging at 0.5 Tfps in passive mode. CUSP combines spectral encoding, pulse splitting, temporal shearing, and compressed sensing, enabling quantitative imaging of rapid nonlinear light-matter interactions and single-shot spectrally resolved fluorescence lifetime imaging microscopy (SR-FLIM).

Peng Wang, Jinyang Liang, Lihong V. Wang