The article presents the results of the formation of a polychromatic edge dislocation. A complex Bragg hologram formed as a complex of two gratings with similar characteristics is used as a device employed for this purpose. It is shown that, under resonant illumination of such a grating in the direction of the zero order, two waves are formed with practically equal intensities, forming a low-frequency interference pattern, at the minima of which edge dislocations are observed. The main idea of the method for the formation of a polychromatic edge dislocation is that such a grating is illuminated by a converging radiation beam with a sufficiently wide spectrum. In this case, the structure itself chooses the resonance angles of illumination of the hologram, and identically localized partial spectral gratings are formed in the zero order. The data of experimental studies are presented. The discussion considered the prospects for the formation of polychromatic azimuthally and radially polarized beams
The possibility of formation of the beam with edge dislocation, which is similar to the ТЕ01(10) beam is considered. It is shown that such mode may be obtained due to the diffraction of plane wave on the complex Bragg hologram, constructed as composition of two grating recorded on the same place of registration media. These partial holograms are implemented as the gratings with constant period and close characteristics. The conditions of such operation are formulated. The experimental results are presented.
The possibility of formation of the beam with edge dislocation, which is similar to the ТЕ01(10) beam is considered. It is
shown that such mode may be obtained due to the diffraction of Gaussian beam on the special binary computer generated
hologram. The conditions of such operation are formulated. The experimental results and results of computer simulation
are presented.
In the paper, we take it into one's head to show how different parameters of an optical wave are connected and what follows from this connection. The results of computer simulation are presented.
The connection between contrast changes of intensity distribution of speckle pattern, obtained for polychromatic
illumination of scattering object and coherence characteristics of wave is considered. It is shown, that changes of mean
contrast of speckle field (from center of pattern toward the periphery), obtained for quasimonochromatic illuminating
wave may by connected with spectral range of the wave. The experimental results are presented.
It was shown that C -points are associated with the singularities of the azimuth of the transversal component of the
averaged the Poynting vector. It is established that Poynting singularity shifts relatively C -point position in depending
of relation between amplitude and phase gradients and absolute values of amplitudes associated with orthogonally
polarized field components. The mean magnitude of such shift is defined by the level of polarization homogeneity of a
field. The dynamic of Poynting singularities and polarization ones changes is considered The results of the computer
simulation and experimental results are presented.
In the paper, we take it into one's head to show how different singularity systems of different parameters of an optical
wave are connected and what follows from this connection. The results of computer simulation are presented.
The behavior of the Pointing vector in the area of elementary polarization singularities with one or two C-points, which
are bounded by regular shape s-contour is considered. It was shown that the disclinations, which move, are born and
annihilate along s-contour, correspond to the singularities of the distribution of the parameters of instantaneous Poynting
vector. C-points are associated with the "vortex" kind singularities of the averaged Pointing vector field if the
handedness factor and topological charge of C-point are characterized by the different signs. "Impassive" Pointing
singularities arise in the area, if the signs are the same. Elementary topology for the Pointing vector field is formulated.
The results of the computer simulation are presented.
Poynting vector singularities are considered for scalar and vector fields. The behavior of averaged and instantaneous
components is analyzed. The relationships between Poynting singularities and conventional optical ones, other special
sets of electromagnetic fields are established. The elementary topological regularities and reactions are formulated. The
results of computer simulation are presented.
The mechanisms of formation and operation of so-called "interference trap" are presented. The formation of the
interference trap by beams with different curvature, ratio of the intensities and phase difference are shown. The results of
the computer simulation of the Poynting vector behavior in the area of the interference trap are analyzed. The
transformation of angular momentum of vortex beam under interference with smooth ones is shown. Distribution of the
transversal component of the Poynting vector for the interference trap, formed by the vortex with different topological
charge is analyzed.
The features of e m inhomogeneous polarized field, which concern an angular momentum, are considered. It is shown
that the e-m field produced by differently polarized optical beams may carry orbital angular momentum. Such angular
momentum arises in field area with the point of circular polarization (C -point). Superposition of relatively simple
orthogonally polarized beams is considered. Experimental results of particles capturing by such focused beam are
presented. On the other hand, in the vicinity of s -contour (field line with linear polarization) spin angular momentum
vanishes. At the same time such angular momentum appears when superposition of beams with different wave-length is
considered.
In this paper we discuss and demonstrate the trapping and manipulating the particles by three types of single traps
(Gaussian trap, vortex trap and "vortex less" trap), which are formed by one optical device. Experimental results are
presented.
Interrelation of the fine structure of the vector field and its averaged polarization characteristics is considered. It is
shown that space averaged Stokes parameters are defined by dispersion of the phase difference in its saddle points. The
dispersion of phase difference and dimension of areas with considerable polarization changes are defied by the
averaged space between the nearest adjacent component vortices of the same sign. The results of computer simulation
and experimental investigation are presented. Good correlation between these results is observed.
It is shown that the polarization singularities of vector field are connected with the presence or absence of the angular momentum of electromagnetic field. In the vicinity of C-point the orbital angular momentum is observed. Direction of influence of such orbital angular momentum is defined by the sign of topological charge of vibration phase in this area. Spin angular momentum of a field vanishes on the s-contour. At the same time similar momentum appears if the resulting field is formed by the waves with different wavelengths.
It is shown that polarization singularities of vector field are connected with the presence or absence of the angular momentum of electromagnetic field. Namely, in the vicinity of C-point the orbital angular momentum is observed, while the spin momentum is indefinite (vanishes) on the s-contour.
The possibility of computer realization of information coding and decoding based on the principles of referenceless holography is considered. The results of preliminary investigations are presented.
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