Effect of Air Nanobubble Clusters on Optical Pulse Propagation in Water

Abstract

Development of mineral resources in the ocean presents the problem of high-speed communication between two underwater objects. Optical radiation provides the highest transmission rate. However, the turbidity of natural waters is strongly variable; therefore, the study of the effects of different components of water suspension on laser pulse transmission is relevant. In the work, propagation of 2-ns optical pulses at a wavelength of 0.514 μm in water containing only clusters of nanobubbles is simulated. The maximal flux of radiation scattered on nanobubble clusters at the entrance to a receiver is shown to be no higher than 10% of the radiation flux propagated without scattering along a path up to 150 m long; the pulse full width at half maximum decreases by no more than 30%. The restriction on the path length in water containing only clusters of nanobubbles is due to radiation attenuation. Our results can be used for prediction of the solar radiation penetration depth during diving operations in water bodies or analyses of images of underwater objects, as well as for the development and usage of equipment for open underwater optical telecommunication lines. The influence of organic and inorganic suspended matter on the laser radiation propagation in water is planned to be studied further.