Evaluation method for underwater polarization image quality applied to laser polarization illumination conditions

In underwater imaging, in order to solve the problem of seawater backward scattering in underwater optical imaging, we can take advantage of the difference in polarization characteristics between the scattered light and the target signal light to improve the imaging quality by combining detected polarization imaging with polarized illumination. How to quantitatively evaluate the effect of polarization imaging with a unified and achievable means is an urgent subject. This paper combines the Stokes vector method to propose a quantitative measurement method of underwater polarized light imaging quality. For the external factors affecting the imaging, evaluating the degree of improvement of the imaging quality under the active laser polarized light illumination. The impurity concentration of the water body was changed to verify the response of the imaging method, the type of illumination source, and the polarization angle under the Stokes vector polarization transmission model, respectively, so as to determine the clarity and information entropy under different impurity concentrations. Compared with the traditional method of determining image improvement, the present method can obtain more accurate quantitative data on underwater polarization description. In this paper, the method is used to quantitatively analyze the polarized image characteristics under active laser polarized illumination conditions, and it is concluded that the clarity improvement can be up to 30% or more, and the information entropy improvement can be up to 10% or more. The method proposed in this paper provides analytical data and means for determining the effect of polarization imaging, thus effectively evaluating the performance of the underwater imaging system.