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In optics, polarization mixing refers to changes in the relative strengths of the Stokes parameters caused by reflection or scattering—see vector radiative transfer—or by changes in the radial orientation of the detector. ==Example: A sloping, specular surface== The definition of the four Stokes components are, in a fixed basis: : where ''E''v and ''E''h are the electric field components in the vertical and horizontal directions respectively. The definitions of the coordinate bases are arbitrary and depend on the orientation of the instrument. In the case of the Fresnel equations, the bases are defined in terms of the surface, with the horizontal being parallel to the surface and the vertical in a plane perpendicular to the surface. When the bases are rotated by 45 degrees around the viewing axis, the definition of the third Stokes component becomes equivalent to that of the second, that is the difference in field intensity between the horizontal and vertical polarizations. Thus, if the instrument is rotated out of plane from the surface upon which it is looking, this will give rise to a signal. The geometry is illustrated in the above figure: is the instrument viewing angle with respect to nadir, We define the slope of the surface in terms of the normal vector, where is the slope and is the azimuth relative to the instrument view. The effective viewing angle can be calculated via a dot product between the two vectors: : from which we compute the reflection coefficients, while the angle of the polarisation plane can be calculated with cross products: : 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「polarization mixing」の詳細全文を読む スポンサード リンク
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