<title>Observation of femtosecond light pulse propagating in space and time</title>

Abstract

We have developed an ultrafast imaging system to record and observe the propagation of femtosecond light pulses in space and time as form of frameless motion picture. To obtain the motion picture, light-in-flight recording of holography using femtosecond pulsed laser is applied. We observed a propagating femtosecond light pulse through a dispersion prism and light pulse train generated from the integrated array illuminator. The temporal and spatial behavior of such ultrashort light pulse in the prism and from the array illuminator is clearly observed. We also demonstrate the propagation of the light pulse through scattering media in three dimensional space. The observed image of the propagating light pulse in the motion picture is different from the actual propagating pulses in shape and velocity. This is common for the light-in-flight recording of holography. These characteristics of the observed image are described.