Polarization Sensing Underwater Target Penetrating Complex Droplet-Bubble Layer

The high-accuracy optical detection of oceanic targets is significantly important but challenging due to the complex conditions around the sea surface, where water droplets and bubbles often interfere with optical signals. These interferences affect both the intensity and direction of the optical signals, making target identification difficult. To address this issue, we propose a theoretical model based on photon tracing to explore the polarization characteristics of oceanic targets in scattering environments. This model tracks the evolution of the state of polarization (SoP) of photons interacting with droplets and bubbles. Utilizing the Monte Carlo algorithm, our model simulates a large number of photon interactions, taking into account the parameters, such as the number density, size distribution of water droplets and bubbles, and the initial polarization state of incident light. Meanwhile, our simulation assumes a homogeneous scattering medium and isotropic scattering properties for computational efficiency. The multidimensional polarization information, combined with upper-hemisphere-space polarization data (UPD), enhances the identification and analysis of oceanic targets. Our results show distinct disparities in UPD for sea scenarios with and without targets, demonstrating the significant potential of our approach for oceanic target detection and polarization sensing.