Research On Target Optical Reflection Characteristics Based On Mueller Matrix

The research on the polarization characteristics of the target optical reflection shows great value and potential in civil and military applications.Study on polarization characteristics of the traditional form of expression,according to the goals of Muller matrix,which can be decomposed into the polarization and depolarization and attenuation module,is a mathematical characterization of the target characteristics,the lack of physical meaning,has certain limitations;and the Maxwell equation and Muller matrix combined with the calculation of the target index using the Muller matrix method derived extinction coefficient,the depolarization coefficient,the coefficient has clear physical meaning and can be used as the new features of the polarization,so as to provide valuable information on the target optical reflection characteristics.Firstly,to solve the most basic Maxwell equations in differential form,wave equation of electromagnetic field intensity vector,based on the target surface is combined with the definition of conductivity,refractive index,optical constants are obtained.Secondly,according to the reflection coefficient of S wave,the amplitude ratio and phase difference of P wave are defined according to the Finel reflection formula.Then according to the measurement of the Muller matrix,and convert it into a Muller Jones Muller matrix,Jones matrix is a reflection coefficient can be expressed by Finel matrix,to solve the problem,you can get the amplitude ratio and phase difference.Finally,combined with the Finel reflection formula and the law of refraction,the expression of the optical constant is obtained.Secondly,a path integral matrix is derived,which has a relationship with the Muller matrix.The path integral matrix is decomposed to obtain the coefficient of depolarization,which can be used to reflect the degree of polarization of the measured object.Because the path integral matrix is the probability mixture of Jones matrix of each beam propagation path,this characteristic makes the path integral matrix a good method for the hybrid material and the physical modeling of the rough surface.And because of the multiple scattering caused by the depolarization,cause multiple scattering of surface curvature is large even when not smooth,so the surface roughness of the back there is a certain relationship between the polarization coefficient and the object,can be used for simulation of rough surfaces,and as an important parameter for target resolution.In order to obtain the Muller matrix of the target itself,this paper designs a kind of multi rotation measuring device.The Muller matrix contains 16 elements,in order to precisely each parameter information in Muller matrix,measurement system firstly construct a multi angle,using seven different incident angle(30 degrees,37.5 degrees,45 degrees,52.5 degrees,60 degrees,67.5 degrees,75 degrees)of target reflection the light is measured,the angle between the incident light and reflected light and normal can change.The control system is used to get 6 sets of different incident Stokes vectors to the target surface,and the 6 sets of reflected light Stokes vectors are measured for each incident light control system.In order to accurately control the system through the polarizer after polarization state of incident light,the beam expanding lens group and a group of circular polarization state generator with partial system between the groups,the intensity of incident light generated by the polarizer system values consistent.Finally,according to the measured target Muller matrix,the polarization parameters which reflect the optical properties of the target are calculated.A large number of experiments are carried out on the typical objects in the natural world and the man-made targets and camouflage targets in complex natural background.The results show that the polarization index is deduced in this paper can distinguish different types of targets,and can analyze different polarization characteristics shown on the target,the target is derived from the theory of optical constants and depolarization coefficient to distinguish target line and practicability.