Computer Optics

4-10

Authors: V.V. Kotlyar, A.A. Kovalev, V.A. Soifer

This paper introduces a new family of diffraction-free asymmetric elegant Bessel beams (EB-beams) with fractional orbital angular momentum (OAM). EB-beams are modes of free space and described by the n-th order Bessel function of the first kind with a complex argument. Functions of complex amplitudes of EB-beams are orthogonal by continuous scaling parameter and not orthogonal on a discrete parameter (topological charge). The intensity distribution of EB-beams has a countable number of isolated zeros of intensity, located on the horizontal axis. These zeros are centers of optical vortices with unit topological charge and opposite signs on different sides of the origin. Isolated intensity zero on the optical axis generates an optical vortex with topological charge of n. OAM of the EB-beams is (n + 0,69777)h per photon, where h is the Planck's constant.

20-27

Authors: E.Yu. Buldygin, D.L. Golovashkin, L.V. Yablokova

The technique of searching of the collateral finite – difference solution of a wave equation and set of equations of Maxwell is offered, allowing to combine advantage and to avoid shortcomings of both made mention numerical methods of nanophotonics (to reduce expenses of memory and to apply well-known TF/SF and PML techniques). In a two – dimensional case on test examples convergence of such decision, possibility of imposing of PML-ayers and a task of an incident wave on the TF/SF technology are shown.

31-37

Authors: A.A. Kovalev, V.V. Kotlyar, S.G. Zaskanov

We propose a method of obtaining solution of the paraxial Helmholtz equation which describes two-dimensional light beams accelerating on a finite interval of the trajectory. Method based on complex conjugation and shift along the longitudinal coordinate (parallel to the optical axis) of the complex amplitude of the slowing light beams. Using this method we obtained Fresnel and Laplace beams, as well as "half-Bessel" beams, accelerating along the trajectory in a form of square root. It has been observed that the well-known Hermite-Gaussian light beams are also accelerating beams with a hyperbolic trajectory. In contrast to well-known diffraction-free accelerating Airy beams all beams, which we consider, are converging upon propagation.

42-50

Authors: A.V. Ustinov, S.N. Khonina

Theoretical and numerical analysis of flat beam diffraction by fracxicon with value of power less than unity are performed within the nonparaxial scalar model. Using integration by parts of the Rayleigh-Sommerfeld integral of first type and applying the modified method of stationary phase we obtain the expression of the axial complex distribution satisfying the boundary conditions for on the optical axis. The results obtained by numerical integration show good agreement with analytical estimates. Numerical examples show that the divergent fracxicon allows to form an extended axial light line with diameter of the order of the wavelength longer and more uniform than provides a linear axicon.

57-66

Authors: S.V. Alferov, S.V. Karpeev, S.N. Khonina, O.Yu. Moiseev

Experimentally investigated a focusing of inhomogeneously polarized laser beams formed by the sector polarizing plates. The analysis of noise distortion beams formed different types of plates is performed. Focusing is implemented by a micro-objective with high numerical aperture and by a diffraction axicon with moderate numerical aperture. It's experimentally shown that beam distortion by noise have a little effect on the intensity distribution in the center of the focus area due to its high frequency nature. It is in agreement with the simulation results.

72-80

Authors: V.V. Kotlyar, S.S. Stafeev, A.Yu. Feldman

It was experimentally shown that square microsteps with width of 0.4 um, 0.5 um, 0.6 um, 0.8 um and height of 500 nm illuminated by linearly polarized laser light with wavelength λ = 633 nm formed near its’ surface focal spots (photonic nanojets) with intensity that is 6 times higher than the intensity of incident light and diameters of 0.44λ, 0.43λ, 0.39λ and 0.47λ (less than the diffraction limit 0.51λ). When the square width was smaller than the wavelength, the focal spot was located inside the step. When the square width was larger than the wavelength, the focal spot was located outside the step and looks like a handle.

87-93

Authors: M.V. Gashnikov, N.I. Glumov

We consider the use of compression method based on hierarchical grid interpolation to compress the hyperspectral images. Approximation of the spectral channels is proposed to improve the efficiency of the method. Recommendations for setting the parameters of the method formulated. Numerical experiments compared to JPEG method implemented.

105-111

Authors: A.A.Vaniev

Article is devoted to the development of methods and criteria for identification of multiple moving objects observed by passive optical digital locator. Approaches to the development of methods of identification of multiple moving objects are examined. Mathematical model of the promising measuring system and some results of practical research are provided. The developed model can be used in various measurement and control systems, real-time observation for the separate estimation of motion of objects in the group.

118-126

Authors: A.A. Sirota, A.Y. Ivankov

Different approaches to block image processing applied to the reconstruction of super-resolution images using the Kalman filter are analyzed. The results of the various approaches are represented.

131-138

Authors: S.S. Sadykov, Yu.A. Bulanova, E.A. Zakharova

This paper proposes a technology of computer diagnosis of tumors in mammary gland of three main types: cyst, fibroadenoma, and breast cancer. It is noted that the use of such technology in the health care setting reduces the chance of missing a tumor when viewing mammograms, are at an early stage of development, but also minimizes the subjectivity of diagnosis. Work on a set of technologies studied real mammograms from MIAS database with known diagnoses. The results of experiments that show the possibility of using the developed based on this technology integrated cabinet in mammography as for general research and well as for screening.

148-153

Authors: M.S. Kasparyan

Introduce an analog cosine transform on the pre-fractal region. From fractal discrete Fourier transform output discrete cosine transform on two-dimensional domains associated with the fundamental domains of number systems in imaginary quadratic rings. It is shown that this transformation is orthogonal.