Infrared polarization visualization of the water surface via dispersion resonance

Advanced infrared polarization recognition technology for water surface targets relies heavily on a comprehensive understanding and accurate modeling of the infrared polarization characteristics of water backgrounds. However, due to the dynamic physicochemical properties of both the atmosphere and the water body itself, measuring the infrared polarization characteristics of water surfaces is highly challenging and often fails to provide accurate data for effective background suppression in polarization-based detection. By introducing the dielectric function, which captures the polarimetric spectral response of water, a polarization model based on the dispersion–resonance mechanism can be established. This approach contributes to the development of a more precise visual model for infrared polarization over water surfaces and enhances our mechanistic understanding of the microscopic origins of infrared polarization in water bodies. Due to its diverse molecular vibration modes, water exhibits multiple resonance peaks in the dielectric function spectrum, which characterizes its electromagnetic response. These resonance features are commonly described by dispersion resonance equations such as the Lorentz model, forming an important theoretical basis for infrared polarization visualization of water surfaces. In this study, we establish a polarization physical model driven by dispersion resonance to describe the polarization characteristics of water surfaces in arbitrary infrared bands and under various altitude angles. Under controlled laboratory temperature conditions, a high-extinction-ratio time-sharing polarization detection system was constructed to measure the infrared degree of polarization of a pure water surface at different altitude angles within a specific waveband. The results show that, under a given atmospheric transmittance, the dispersion–resonance-driven polarization model can quantitatively characterize the infrared polarization properties of the water surface.