In this paper, infrared polarization detection information acquisition technology is proposed, and the polarization characteristics of oil spills are modeled and studied. A set of long-wave infrared polarization detection equipment for oil spills is designed and built, and modeling research on oil spill polarization characteristics is carried out to accurately detect and identify oil spill types and for the faster processing of oil spill events. Oil spill accuracy is increased by defining the polarization maintenance method of the polarization optical system and reducing the polarization measurement error brought on by the imaging system. As a result, a higher than 3% contrast exists between the polarization degree image and the corrected infrared intensity image. Outdoor tests using oil, palm oil, crude oil, gasoline, and diesel oil spill types are carried out in a controlled environment to collect data on the polarization of various oil species. According to the findings, each oil species’ infrared polarization contrast with seawater is typically greater than its infrared intensity contrast. However, the polarization data of saltwater, diesel, and palm oil, which are difficult to identify in intensity data, show a noticeable difference, further proving the viability of utilizing polarization to discern oil spills.

This paper addresses the objectives in a complex context: the polarization mathematical and physical model of the basic components of the target/background is constructed by simulation modeling. The image fusion experiment is carried out based on a two-dimensional wavelet transformation. A high-resolution polarization imaging instrument was developed, and static experiments were carried out with polarization, infrared, and visible cameras. The result shows that using polarization imaging detection technology to detect physical evidence targets in complex backgrounds can effectively improve target contrast. It can enrich the target information, improve image quality, and improve target detection accuracy.

In order to meet the requirements of target detection at different distances in infrared polarization detection, a transmission-type long-wave infrared polarization zoom optical system is designed, can zoom in 18–90 mm and the wavelength range is 8–14 μm. The spatial resolution is 0.18–0.9 mrad, and the machining and assembly errors are analyzed. Based on BRDF and Stokes vector model, aluminum is spontaneous emission, and reflected emission characteristics under specific conditions are simulated and analyzed. Infrared polarization imaging and island imaging experiments verify the unique advantages of infrared polarization technology in distinguishing natural and manufactured objects, metal and non-metal, and high-temperature object recognition. The changing trend of contrast between infrared intensity image and polarization image with solar altitude angle is explored, providing theoretical support for developing an infrared photoelectric detection field.

The incidence angle of a beam entering a liquid crystal variable retarder (LCVR) and the liquid crystal polarization grating (LCPG) is greater when the LCPG is utilized in the quadrature cascade, which reduces the diffraction efficiency. Therefore, this study investigates the best method for controlling a cascaded LCPG. By optimizing the control coefficient and the method for controlling the voltage of the LCVR, this study reduces the angle between the incident LCVR and the polarization grating, and increases the diffraction efficiency of the grating. It was confirmed that this strategy can increase the diffraction effectiveness of the quadrature cascaded LCPG through the design of the experimental setup.

Considering the advancement in marine research in recent years, studies on the identification of offshore scenery are becoming popular globally. In this study, multiband polarimetric imaging is presented to address the deficiencies of the previous single-band study. Polarization imaging experiments of sea fog and non-sea fog in an indoor simulated environment are carried out and compared and analyzed by establishing an artificial simulation system to characterize the sea fog concentration by optical thickness with different concentrations of sea fog environment as the medium. The polarization information of each waveband converted by Stokes parametric is then brought into the two-dimensional discrete wavelet algorithm for image fusion processing. The findings indicate that when the optical thickness of sea fog increases, the polarized light in the chaotic medium recedes and the effect of the image blurs. Finally, after the image fusion process, the contrast of the image is improved and the detail of the target contour is obvious, which proves that the method has good robustness under the low signal-to-noise ratio of the sea fog environment. This provides a solid platform for targeted surveys and civic operations under dense marine fog conditions.

Addressing unstable stratified oceanic turbulence, this paper develops a composite stratified oceanic turbulent phase screen model using power spectrum inversion, which fully accounts for the coupled effects of turbulence diffusion, absorption, and scattering. We investigate the intensity and phase evolution of Perfect Vortex Beams (PVBs) after propagation, comprehensively analyzing scintillation index variations across different topological charges, propagation distances, and turbulence parameters, alongside the Bit Error Rate (BER) of OOK-modulated underwater wireless optical communication (UWOC) systems. To mitigate turbulence-induced fading, multi-aperture reception is introduced, with performance gains evaluated as a function of aperture diameter D and number N. Results show that at propagation distances exceeding 55 m, higher-order PVBs exhibit significantly lower scintillation indices than lower-order ones due to their superior topological stability. Scintillation and BER intensify with decreasing kinetic energy dissipation or increasing mean-square temperature dissipation and temperature–salinity balance parameters, with temperature dissipation being the dominant factor. Multi-aperture reception effectively smooths channel fading by leveraging intensity fluctuation decorrelation. The equivalent scintillation index decreases significantly with increasing N and D, though marginal gains diminish as N grows. In weak turbulence, increasing D from 0.02 m to 0.06 m for a single aperture reduces the scintillation index by 46.3%; when the aperture number increases from N = 1 to 2, the equivalent scintillation index drops by an average of approximately 42%, confirming that N = 4~6 provides an optimal trade-off between complexity and performance. In strong turbulence, multi-aperture reception efficiency is higher; the first three apertures contribute approximately 65% of the total gain, and the marginal gain inflection point shifts from N ≈ 7 to N ≈ 5. This study provides a theoretical basis for designing robust UWOC systems.