Krishnan S, Nordine P C
Appl Opt. 1994 Jul 1;33(19):4184-92. doi: 10.1364/AO.33.004184.
A fully automated Mueller-matrix ellipsometer with a division-of-amplitude photopolarimeter as the polarization-state detector is described. This device achieves Mueller-matrix ellipsometry by measuring the Stokes parameters of reflected light as a function of the fast axis C of a quarter-wave retarder, which, in combination with a fixed linear polarizer, determines the polarization state of incident light. The reflected Stokes parameters were Fourier analyzed to give the 16 elements of the Mueller matrix. We investigated depolarization of polarized light on reflection from rough, heterogeneous, and anisotropic surfaces by obtaining measurements on rolled aluminum and plant leaves. The results demonstrate (1) a variation of degree of polarization of reflected light with the input polarization state, (2) the precision with which the measured matrices describe the depolarization results, (3) effects of surface anisotropy (rolling direction) on depolarization and cross polarization by reflection from aluminum surfaces, and (4) large values and differences in the depolarization effects from conifer and deciduous leaves. Depolarization of light reflected by the aluminum surfaces was most sensitive to the angle between the plane of incidence and the rolling direction when the incident Stokes parameters S(1), S(2), and S(3) were equal.
本文描述了一种全自动穆勒矩阵椭偏仪，它采用分振幅光偏振计作为偏振态探测器。该装置通过测量作为四分之一波片快轴C函数的反射光的斯托克斯参数来实现穆勒矩阵椭偏测量，四分之一波片与固定线性偏振器相结合，决定了入射光的偏振态。对反射的斯托克斯参数进行傅里叶分析，得到穆勒矩阵的16个元素。我们通过对轧制铝和植物叶片进行测量，研究了偏振光在粗糙、非均匀和各向异性表面反射时的退偏现象。结果表明：(1)反射光的偏振度随输入偏振态的变化；(2)测量矩阵描述退偏结果的精度；(3)表面各向异性(轧制方向)对铝表面反射引起的退偏和交叉偏振的影响；(4)针叶和落叶的退偏效应的大值和差异。当入射斯托克斯参数S(1)、S(2)和S(3)相等时，铝表面反射光的退偏对入射角和轧制方向之间的夹角最为敏感。
