Figure 4: A single frame from the supplementary material video 7, showing multiple individual pulses at 780 nm propagating through the optical fiber with a repetition frequency of 1 GHz corresponding to a pulse separation of 1 ns.
From: Observation of laser pulse propagation in optical fibers with a SPAD camera

The processed data from the the camera is overlaid on top of a digital camera still image of the fiber in-situ.