Remote sensing for oil products on water surface via fluorescence induced by UV filaments

摘要

Remote monitoring of water pollution, namely thin films of oil or oil products on water surface, can be carried out by laser fluorimetry. The pollutants fluorescence during its interaction with ultrashort UV laser pulses was experimentally studied in this paper. The laser pulses power was considered in a wide range of values including the filamentation regime. We compared fluorescence stimulated by femtosecond UV laser pulses with two central wavelengths (248 and 372 nm) for detection of crude oil and the following oil products: oil VM-5, oil 5W-40 and solvent WhiteSpirit. It was shown that shorter UV wavelengths are more suitable for fluorescence excitation. The spatial resolution of the fluorescence localization was no worse than 30 cm. We discuss techniques of high intensity emission delivery to the remote target as post-filamentation channels and multifilamentation beam propagation regime as well experimentally and numerically.