Oceanic turbulence effects on long-exposure and short-exposure imaging

摘要

Based on the power spectrum of oceanic turbulence, the modulation transfer functions and the optical resolution for long-exposure and short-exposure imaging through oceanic turbulence are studied in detail. The analytical formulae for the seeing parameter and the tilt variance in oceanic turbulence are derived, and it is found that the relationship between the seeing parameter and the spatial coherence width in oceanic turbulence is just like that in atmospheric turbulence. Furthermore, the model of underwater imaging shown in this paper considers both temperature and salinity fluctuations for oceanic turbulence. It is found that, compared with the dominating salinity-induced turbulence, the range of angular spatial frequency where oceanic turbulence plays the major role rather than particle scattering is higher for the dominating temperature-induced turbulence.