Study On Polarization Characteristics Of Rough Objects Based On Mueller Matrix

Scattering of light waves by rough objects will cause depolarization,and the degree of depolarization caused by different roughness is also different.Mastering the polarization characteristics of rough objects is important for target detection,material identification,and military stealth.Mueller matrix is a four-dimensional matrix,reflecting the diattenuation,retarder,polarization,depolarization and other characteristics of light waves.It contains almost all the surface feature information of the object,such as material and surface roughness,it is an important method to obtain polarization information of objects.Therefore,this paper uses the Mueller matrix to study the polarization characteristics of rough objects.The specific work is as follows:1.The rotating Mueller matrix measuring device was selected to measure the Mueller matrix of three metal targets of copper foil,aluminum and steel under different roughness.The experimental device is mainly composed of five parts: He-Ne laser,circularly polarized light generating system,polarizing system,analyzer system and CCD.By repeatedly adjusting the polarizer and ?/4 wave plate in the polarizing system and the analyzer system,the Mueller matrix of the target is measured and calculated.2.The effects of roughness on the components of the Mueller matrix of copper foil,aluminum and steel are analyzed.The result shows that the roughness has a great influence on the eight Mueller matrices components of m00 ?m01 ?m10 ?m11 ?m22?m23?m32?m33 and a small influence on the other eight components.As the roughness decreases,the m01 and m10 of the three metals gradually increase,indicating that the horizontal diattenuation ability and the polarization ability of the sample are enhanced;m11 gradually decreases,indicating that the depolarization ability caused by the sample's ability to reflect light intensity decreases;m22 ?m23?m32 ?m33 reflect the depolarization caused by the phase delay of the sample,but m22?m33 shows a decreasing trend,m23?m32 shows an increasing trend,and the overall depolarizing capability is uncertain.3.Since a single component in the Mueller matrix cannot fully describe the polarization characteristics of the sample,this article decomposes the Mueller matrix to obtain three independent sub-matrices and three parameters representing the sub-matrix,scatteringdepolarization ?,diattenuator D,retarder R.The analysis results show that as the roughness decreases,the ?value of the three metals decreases,the D value increases,and the R value changes smoothly,indicating that the overall depolarization ability of the sample is weakened,and the diattenuation ability is enhanced,which has little effect on the delay characteristic.