Computer Optics

644-653

Authors: Paranin V.D., Karpeev S.V., Krasnov A.P.

An optical system for converting circularly polarized laser beams into cylindrical vector beams on the basis of anisotropic crystals has been developed. Polarization properties and the structure of the resulting beams have been experimentally characterized. The analysis has revealed differences in the azimuthal and radial polarization of Gaussian modes and Bessel beams. Ranges of variation of the optical system parameters to form different types of polarizations with different amplitude and phase distributions have been identified.

663-673

Authors: Bykov D. A., Doskolovich L. L.

We propose a generalization of the Fourier modal method aimed at calculating localized eigenmodes of integrated optical resonators. Te method is based on constructing an analytical continuation of the structure’s scattering matrix and calculating its poles. The method allows one to calculate the complex frequency of the localized mode and the corresponding field distribution. We used the proposed method to calculate modes of a rectangular dielectric block located on a metal surface. We show that the excitation of these modes by the surface plasmon-polariton (SPP) results in resonant features in the SPP transmission spectrum. In a magnetized structure, the mode excitation results in resonant magneto-optical effects. The proposed method can be used to design and investigate optical properties of integrated and plasmonic optical devices.

678-686

Authors: Belousov D.A., Poleshchuk A.G., Khomutov V.N.

We propose a method and a design of a device for an on-line monitoring of a spatial intensity distribution of transmitted and reflected diffraction orders found within a ±80° solid angle and a 360° azimuthal angle. The proposed device is intended to serve as a shape and depth profiler of the diffractive element microrelief in the course of manufacturing.

694-701

Authors: Klykov S.S., Fedosov I.V., Tuchin V.V.

We analyze forces that act in an optical trap on a biological cell modeled by a dielectric microsphere moving in a fluid. Analysis of the microsphere’s dynamical behavior has enabled key parameters for trapping of the cell to be identified, including the fluid viscosity and the laser beam power.

709-715

Authors: Stafeev S.S., Nalimov A.G., Kotlyar M.V., O’Faolain L.

In this paper, we have designed and fabricated a four-zone binary subwavelength reflective micropolarizer. The 100×100-μm micropolarizer grating was synthesized by electron-beam lithography. FDTD-based numerical simulation and experimental characterization have shown the micropolarizer to be capable of transforming a linearly polarized incident Gaussian beam of wavelength 532 nm into an azimuthally polarized beam.

721-727

Authors: Anchikov D.A., Krents A.A., Krestin S.V., Molevich N.E., Pakhomov A.V.

In this paper, we investigate a model of wide-aperture vertical-cavity surface-emitting semiconductor VCSESL based on the complete set of two- dimensional Maxwell-Bloch equations on circular and square apertures. The results of numerical simulation in near and far fields are shown in relation to frequency detuning, which can be presented in semiconductor lasers as a function of temperature. The simulation results are compared with the experimental data and theoretical predictions.

738-743

Authors: Tsvetkov O.V., Tananykina L.V.

In this paper we discuss an image preprocessing method for different shooting conditions. The method can be applied in machine vision systems using a correlation-extremal mapping method. An information-theoretic method for image preprocessing based on entropy analysis is offered. The investigation of the method has shown that, when preprocessed, same-scene images obtained under different conditions have a more stable correlation coefficient than the original images.

751-761

Authors: Sirota A.A., Dryuchenko M.A.

A problem of image compression in arbitrarily-shaped fragments is considered. A theoretical substantiation of hetero- and auto-associative compressive transformations on random fields fragments using neural networks is given.

770-776

Authors: Goshin Ye.V., Fursov V.A.

In this paper we consider an information technology of 3D scene reconstruction from stereo images which were obtained from a camera with unknown extrinsic parameters. The main idea of the present paper is to compute rotation and translation of the camera directly from the corresponding points.

787-794

Authors: Soldatova O.P., Lyozin I.A., Lyozina I.V., Kupriyanov A.V., Kirsh D.V.

The article proposes the application of neural fuzzy networks for defining the overlapping classes of crystal lattices. We discuss the following neural fuzzy networks: Takagi-Sugeno-Kung network and a modification of Wang-Mendel neural fuzzy network proposed by the authors. A three-step scheme of neural network training is proposed. The results prove the efficiency of the proposed approach for the determination of crystal lattice types.

801-807

Authors: Vorotnikova D.G., Kochurov A.V., Golovashkin D.L.

We propose models of GPU (graphics processing unit) computing that can be recommended for implementation of explicit and implicit difference schemes on GPUs. In particular, these are models for selecting an optimal vector length in the 'long-vector' algorithms and for finding an optimal pyramid height in corresponding parallel algorithms.

818-822

Authors: Boori M.S., Kuznetsov A.V., Choudhary K.К., Kupriyanov A.V.

In the present paper, satellite image classification methods were applied to extract four main types of land use: water resources, built-up areas, forests and agricultural land. To evaluate in which way the urban growth and land use changes occurred in the city of Samara, Landsat satellite images taken at five different time periods over the years 1975-2015 were employed. Changes in all types of land use at different periods of time were calculated using the ArcGIS Software with due regard for population changes. The estimation of changes in the built-up area was conducted in relation to the population development.