Study On Polarization Imaging Characteristics Of Target Based On Polarization Detection

After the light wave is reflected and scattered by the surface of the object,the polarization state will change,and many information of the target will be loaded.Polarization detection technology acquires target information by detecting changes in the polarization state before and after the light wave illuminates the object.The Mueller matrix can well describe the change of the polarization state of the light wave in the polarization detection technology,and is an important means to obtain the polarization characteristics of the target.However,the measurement of Mueller matrix is greatly influenced by the material,surface roughness,surrounding environment and incident angle.Therefore,this paper focuses on the influence of different incident angles on the target Mueller matrix.And then the relationship between incident angle and polarization indicators such as bidirectional attenuation parameters,polarization parameters,depolarization index were analyzed.The specific work is as follows:The Mueller matrix of metal targets(copper sheets,aluminum sheets,steel sheets)and non-metal targets(silicon wafers,sapphire sheets)at different incident angles was measured using a multi-rotation Mueller matrix measuring device.The experimental device for measurement consists of a circularly polarized light generating system,a polarizing system,and a analyzer system.In order to make the data processing simple,the rotation angles of the polarizing plate and the wave plate of the polarizing system are designed to obtain the incident light of six special polarization states,and the rotation angles of the polarization plate and the wave plate of the analyzer system are designed to obtain six kinds of special detection.The Mueller matrix of the system is used to solve the Mueller matrix of the target according to the relationship between Stokes and Mueller matrix.The effects of the incident angle on the components of the Mueller matrix of three metal materials and two non-metallic materials,and the influence of the target polarization index are analyzed.The results show that the incident angles have a great influence on the eight Mueller matrix components m00、m01、m10、m11、m22、m23、m32、m3.As the incident angle increases,the bidirectional attenuation parameters of copper,aluminum,silicon and sapphire are gradually increased.The variation of the sheet is small;the polarization parameters of the copper and sapphire sheets are gradually increased,the silicon wafer is gradually reduced,the aluminum sheet is first reduced and then increased,and the incident angle is 60 and the polarization parameter of the steel sheet changes little.However,the numerical value is the largest;the depolarization index of copper sheets and steel sheets is gradually increased,and the depolarization index of aluminum sheets,silicon sheets,and sapphire sheets is first decreased and then increased,and the sapphire sheet is the strongest when the incident angle is 50°.The silicon wafer has the strongest depolarization at an incident angle of 70°.