THE VISUAL MANIFESTATION OF THE OPTOACOUSTIC EFFECT IN FILMS ON WATER
Recently, in the laboratory experiments we have presented effect of sound generation in air seems like «crackling» when a film on the water surface was irradiated by IR- laser radiation with a wavelength of 10.5 μm. For clean water surface, no crackling was detected. It means, that film presence significantly changed the conditions for the formation of local heating areas in water and acoustic waves emission. The sound characteristics were preliminarily investigated depending on the water temperature, the film thickness and its substance, as well as the radiation intensity. However, the effect insufficient repeatability in some experiments stimulated additional studies of the observed optoacoustic effect in order to obtain visual information about the processes occurring in the irradiated area using video recording. This study results are presented in this paper on the example of a laboratory and field experiments.