High-speed holographic visualisation of processes in transparent media

A fast holographic cinematography method was used in the investigation of optical inhomogeneities in transparent media (plasma, gases and liquids, including active media of lasers, transparent solids). Experiments showed that the relaxation of active media of dye lasers with flash lamp excitation has the form of pulses representing a sequence of the appearance and decay of inhomogeneities which are optically equivalent to a spherical lens with a focal length that increases from one period to the next.