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The light polarization and its process of propagation are mutually independent under a narrow light beam propagation through a homogeneous medium. But it is not correct for the case of inhomogeneous medium. The influence of the trajectory on the light polarization consists in the rotation of the polarization plane under light propagation along the nonpianar trajectory [1, 2]. The influence of the polarization on the light trajectory manifests itself under the total internal reflection. A linearly polarized reflected ray suffers a longitudinal shift [3, 4], and a circular polarized ray suffers transverse shift [5, 6]. It should be stressed that those investigations were independent and the effects were not considered as a result of manifestation of mutual influence of the polarization of the light and its propagation. For the first time professor B.Ya.Zel'dovich, dealing with the light propagation through a multimode optical fiber, has pointed out that the influence of the trajectory on light polarization and the influence of polarization on the light trajectory are mutually inverse effects [7]. On that base optical Magnus effect was predicted [711 and experimentally observed [8]. Optical Magnus effect manifests itself as a rotation of the speckle pattern of the circular polarized light transmitted through a multimode optical fiber under circular polarization sign change. In terms of quantum mechanics that effect was regarded as an interaction between orbital momentum of photon and its spin (polarization) [7]. All mentioned above effects exist in optically inhomogeneous medium. We can supposed that spin-orbit interaction of a photon manifests itself due to break down of the symmetry of a space, namely, the translation symmetry. Nevertheless, it was shown and experimentally observed that there exist influence of the polarization on the light trajectory under the light propagation through an optically homogeneous medium [9, 10]. That effect manifests itself under circular polarized light propagation through a half of lens: the focal spot of a beam suffers a transverse shift under circular polarization sign change. In that particular case the manifestation of spin-orbit interaction of a photon can be considered as a result of break down of the axial symmetry of a medium. That interpretation allows us to predict the existence of the inverse effect — the influence of the polarization on the light propagation in a homogeneous medium. Let us consider the propagation of the linear polarized light through a half of lens. The linear polarized light can be considered as a superposition of the left and right circular polarized light. According to [9, 10] the centers of gravity of the left and right circular polarized light will not coincide. Let us screen the half of the focal plane. The estimation based on the results [9] has shown that the transmitted light will be right or left elliptically polarized with degree of the ellipticity < iO. That scheme was experimentally realized. The change of the ellipticity of the correct sign was observed. The preliminary results were reported in [11]. That effect can be also considered as the geometric light depolarization.
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