Research On The Detection Method Of Oil Spill On Water Surface Based On Polarization

Oil spill pollution is not only the highest proportion of water environmental pollution,but also the most serious pollution type,so it is very important to implement efficient and effective monitoring and identification methods of oil spill pollution.In the methods of detecting oil spill pollution,the traditional remote sensing only considers the radiation intensity and geometric characteristics of electromagnetic wave,and loses a lot of information.The polarization remote sensing is a useful supplement to the traditional remote sensing,which describes the radiation intensity,direction,phase and polarization state of electromagnetic wave.Because the difference of surface structure,internal structure and incident angle,the polarization state of oil spill will change during the interaction with light.Mueller matrix can describe the change of polarization state of light wave,and it is an important method to obtain the polarization characteristics of oil spill surface.Therefore,this paper uses polarization remote sensing technology to build a Muller matrix measurement system and design a method to extract the characteristic parameters of oil spill.The improvement of the calculation method is helpful to improve the accuracy of oil spill recognition and provide the theoretical basis for the optical recognition mechanism of oil spill.It has important scientific significance and practical application value.Mainly including the following contents:Firstly,this paper studies the domestic and foreign literature of traditional remote sensing detection and optical remote sensing detection,describes the development of polarization detection in the identification of surface oil spill,analyzes the theoretical basis of polarized light,and describes the mathematical characterization of polarized light and polarization element in detail.Secondly,this paper adopts the multiangle double rotation Muller matrix measuring device to study the Muller matrix and measuring method,and designs the calculation method of the optical constant of oil spill.The Mueller Jones matrix is derived from the Mueller matrix and the Fresnel formula is combined to establish the relationship between the polarization characteristics of the sample surface and the incident angle,and the optical constants are theoretically derived.And analyzes the feasibility of detecting oil spill by optical constants.Finally,the Mueller matrix of oil spill samples at different incident angles was measured in a dark room,and the Mueller-Jones matrix was solved by combining Fresnel equation.The difference of amplitude ratio,phase retardation,degree of polarization and refractive index between oil film and water was calculated by the multiangle integral calculation method.In addition,this paper proposes a new multiangle pixel calculation method,which selects several pixels in the image and calculates the polarization parameters of each pixel.The accuracy of this method is higher than that of multiangle integral calculation method,and the recognition is more accurate.