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Speaking about the oblique Talbot effect, one usually assumes the case when the diffraction grating is illuminated by a plane wave at an angle, while the screen for observing the diffraction pattern is located parallel to the plane of the diffraction grating. At the same time, as the presented consideration shows, if the grating is illuminated at an angle, then in order to observe the Talbot effect, the observation screen must be tilted as well. In the present work, we considered the inclined Talbot effect for a grating with a finite number of slits, when the observation of the diffraction pattern and the illumination of the grating are performed at an angle. The dependence of the Talbot length on the angles of observation and illumination is determined. It is shown that the effect of self-reproduction can be observed only at certain values of these angles. It is proved that the value of the Talbot length does not depend on the parity of the number of lattice slits. At the same time, the number of slits determines the character of the distribution of maximums on the screen. Thus, in the case of a diffraction grating with an even number of slits, a maximum is observed in the center of the screen. In the case of a grating with an odd number of slits, the pattern of maximums is shifted by half the period of the grating compared to the pattern of maximums in the case of gratings with an even number of slits. [ABSTRACT FROM AUTHOR]

The description of the superposition field generated by a system of wave source points with coherent emission is discussed in this paper. The conditions for the problem parameters are identified in a general form, which enable satisfactory description of wave field within the framework of Fresnel and Fraunhofer approximations, respectively. In the presented approach a number of known results of the wave theory are reproduced, which are used for directional amplification. These results are summarized for the Fresnel diffraction case. The possibility to obtain a superposition field with point amplification is considered. [ABSTRACT FROM AUTHOR]

The problem of a wave field description for a harmonic in time plane wave propagating through arbitrary one dimensional absorbing media is considered. The analysis is performed in the framework of the so-called approach of counter-propagating waves developed for a case of the normal incidence, so that the results given in this work can be considered in many respects as a generalization on this approach. The suggested approach is also applied for calculations of a space distribution of a wave field both inside and outside of different layered structures. [ABSTRACT FROM AUTHOR]

In the paper the character of the phase relationships between oscillations at different points of the wave field generated by two coherent point sources is discussed. It is shown that on the surfaces of the maxima and minima of the amplitude, the in-phase or anti-phase of the oscillations is determined by the multiplicity of the path sum to the wavelength. The locations of the phase points in the interference pattern were defined. [ABSTRACT FROM AUTHOR]

Abstract: A simple and effective method to measure an electromagnetic wave polarization plane''s weak rotations in various media is proposed. The specific features of the polarization plane''s rotation amplification for the light reflection and transmission through the absorbing and amplifying isotropic layers are calculated. The amplification effects on an anisotropic and cholesteric liquid crystal (CLC) layers are also considered. In conclusion the question of probable choice of the amplifier''s noise/signal ratio is discussed. [Copyright &y& Elsevier]