Polarization Detection And Characteristics Of Scattered Light In Track Wake

Aiming at the wake generated by the ship during navigation,the study of its optical characteristics can be used to identify and track the ship.Moreover,the light wake-guided torpedoes made by the light scattering effect of the ship’s wake are useful in the defense and military fields.Great application prospect.The study of the bubble curtain in the wake is the basis of the wake study.The results of the study of the optical characteristics,geometric characteristics and motion characteristics of the bubbles can be widely applied to many fields,such as sea surveillance law enforcement,water quality monitoring,marine fish school detection,etc.Therefore,the research value of wake bubble optical properties is extremely important.In addition,polarization is one of the essential properties of light.It has natural physical characteristics.By using the change of the polarization state of the polarized light in the transmission of the bubble curtain,the polarization information of the bubble curtain can be obtained as an important indicator for the detection of the bubble curtain.The study of the polarization characteristics of curtain scattered light can better understand the optical characteristics of wake bubbles.Based on this,this paper systematically studies the optical characteristics of light scattered by wake bubbles from two aspects,simulation and experiment.This thesis embarks from the research on light scattering properties of a single bubble,combined with the Mie scattering theory,calculated the optical efficiency factor of a single bubble,scattered light intensity distribution and polarization degree distribution,on this basis,further discussed the light scattering properties of bubble curtains,including bubble curtain of scattered light intensity distribution and phase function distribution characteristics,etc.Because the Mie scattering theory research bubble curtains,light scattering characteristics of bubble curtains is only a single bubble light scattering properties of linear superposition,not considering the related between the photon scattering.In order to verify the simulation results,experimental studies were performed on the intensity and polarization characteristics of forward-scattered light of the bubble curtain,including the effects of different media,different pressures,different optical thicknesses,and different scattering angles on the intensity and polarization of forward-scattered light.It is obtained that with the increase of the optical thickness,the degree of polarization DOP of incident light in different polarization states decreases to different degrees,showing a depolarization phenomenon,and under the same conditions,circularly polarized light compared to linearly polarized light Conclusion of better polarization.Finally,the agreement between the simulation and the experimental results is verified,and it is found that the simulation and the experimental results are consistent in the overall trend,and the confidence reaches more than 60%,indicating that the simulation and the experimental results are basically consistent.In addition,when Monte Carlo method is used to simulate the scattering of photons between bubble curtains,the effect of multiple scattering is considered,which is closer to the scattering of photons between bubble curtains in the experiment.Therefore,its confidence is more than that of Mie scattering simulation method.High,further illustrating the superiority of Monte Carlo method in the accuracy of multiple scattering simulation.The combination of experiments and simulations used in this paper has a certain impetus for the research of wake bubble scattering light polarization detection.