Observation of propagating femtosecond light pulse train generated by an integrated array illuminator as a spatially and temporally continuous motion picture

Motion-picture recording of ultrafast behavior of polarized light incident at Brewster's angle

Observing light propagation plays an important role in clarifying ultrafast phenomena occurring on femtosecond to picosecond time scales. In particular, observing the ultrafast behavior of polarized light is useful for various fields. We have developed a technique based on Polarization Light-in-Flight Holography, which can record light propagation as a motion picture that can provide information about the polarization direction. Here we demonstrate motion-picture recording of a phenomenon, which is characteristic of polarized light, by using the proposed technique. As a phenomenon, we adopted the behavior of a light pulse incident at Brewster’s angle. We succeeded in recording the light reflection of specific polarized light by the proposed optical setup. The method of recording the motion-picture, reconstruction procedure, and the quantitative evaluation of the results are demonstrated.

Extending recordable time of light-in-flight recording by holography with double reference light pulses

Light-in-flight (LIF) recording by holography is a powerful technique for observing ultrashort light pulse propagation. However, the recordable time of the technique has been limited by the lateral length of the holographic plate. Then, to extend the recordable time of LIF recording by holography, we proposed a space-division multiplexing technique of holograms, which divides the holographic plate longitudinally and uses double reference light pulses. We experimentally demonstrated that the recordable time becomes twice as long as before for the first time, to the best of our knowledge, using the proposed technique. Specifically, we recorded the motion picture of the ultrashort light pulse propagation for 236 ps.

Moving picture recording and observation of three-dimensional image of femtosecond light pulse propagation

We recorded and observed, for the first time, three-dimensional image of femtosecond light pulse propagation as continuous moving picture using light-in-flight recording by holography. We present the moving pictures of collimated and converging light pulses and some images extracted from them. We also discussed inherent feature appearing in the images. Such a discussion is essential to determine the actual shape of the propagating light pulse. This technique provides the means for observation of a temporally and spatially continuous moving picture of light itself and also enables the analysis of various kinds of ultrafast phenomena.