2006 年 26 巻 Supplement2 号 p. 223-226
We present a technique to record and observe motion picture of three-dimensional image of femtosecond light pulse propagation. The technique was attained by light-in-flight recording by holography. The holography uses an ultrashort pulsed laser as an optical source for the recording. To record the three-dimensional image of light pulse propagation, weakly diffusive medium with adequate volume was introduced to the recording optical setup of conventional light-in-flight recording by holography. Temporally and spatially continuous motion pictures of three-dimensional images of a 373-femtosecond light pulse propagating in gelatin jelly were observed. We found from the motion pictures that the shape of the reconstructed image was horizontally flipped. To analyze the flip, we modeled image-recording and reconstructing process in the technique and numerically simulated the shape of the image based on the model. The shape of the reconstructed image in the simulation agreed with that of experimental result, thus the validity of the modeling and analysis was verified.