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1.
Appl Opt ; 55(12): B67-71, 2016 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-27140134

RESUMO

An optical model for generalized optical anisotropy of polycrystalline networks of albumin and globulin liquor of the human brain has been suggested. The polarization-phase method for spatial and frequency differentiation of linear and circular birefringence coordinate distributions has been analytically substantiated. A set of criteria documenting the dynamics of polarization-phase images of liquor polycrystalline films has been identified in determining time of death.


Assuntos
Morte , Microscopia de Polarização/métodos , Anisotropia , Birrefringência , Análise de Fourier , Humanos , Fatores de Tempo
2.
Appl Opt ; 55(12): B78-84, 2016 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-27140136

RESUMO

The paper presents principal approaches to diagnosing the structure-forming skeleton of a complex optical field. Analysis of optical field singularity algorithms, depending on intensity discretization and image resolution, has been carried out. An optimal approach is chosen, which allows us to get much closer to the solution of the phase problem of localization speckle-field special points. The use of a "window" 2D Hilbert transform for reconstruction of the phase distribution of the intensity of a speckle field is proposed. It is shown that the advantage of this approach consists in the invariance of a phase map to a position change of the kernel of transformation and in a possibility to reconstruct the structure-forming elements of the skeleton of an optical field, including singular points and saddle points. We demonstrate the possibility to reconstruct the equi-phase lines within a narrow confidence interval and introduce an additional algorithm for solving the phase problem for random 2D intensity distributions.

3.
Appl Opt ; 53(10): B159-66, 2014 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-24787199

RESUMO

The piezoelectric photoacoustics application possibility for polycrystalline structure formation has been considered. The accent was on research and transient modeling with pulse laser irradiation. A mathematical model for the given setup with a single laser impulse was developed. The results of mathematical modeling were experimentally tested on cement samples.

4.
Opt Express ; 22(5): 6186-93, 2014 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-24663952

RESUMO

We propose an optical correlation algorithm illustrating a new general method for reconstructing the phase skeleton of complex optical fields from the measured two-dimensional intensity distribution. The core of the algorithm consists in locating the saddle points of the intensity distribution and connecting such points into nets by the lines of intensity gradient that are closely associated with the equi-phase lines of the field. This algorithm provides a new partial solution to the inverse problem in optics commonly referred to as the phase problem.

5.
Appl Opt ; 51(10): C208-14, 2012 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-22505102

RESUMO

This paper discusses simulation of speckle-field dynamics during coherent light scattering by a cement surface in the process of hydration. Cement particles are represented by the spheres whose sizes and reflection indices are changing during the hydration process. The study of intensity fluctuations of scattered coherent radiation is a suitable technique for the analysis of both fast and slow processes of mineral binder hydration and formation of polycrystalline structures in the process of hardening. The results of simulation are in good agreement with the experimental data.

6.
Opt Express ; 19(2): 660-72, 2011 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-21263605

RESUMO

We present the computer simulation results of the spatial distribution of the Poynting vector and illustrate motion of micro and nanoparticles in spatially inhomogeneously polarized fields. The influence of phase relations and the degree of mutual coherence of superimposing waves in the arrangements of two-wave and four-wave superposition on the characteristics of the microparticle's motion has been analyzed. The prospects of studying temporal coherence using the proposed approach are made. For the first time, the possibility of diagnostics of optical currents in liquids caused by polarization characteristics of an optical field alone, using nanoscale metallic particles has been shown experimentally.


Assuntos
Luz , Metais/química , Modelos Químicos , Nanopartículas/química , Espalhamento de Radiação , Simulação por Computador , Metais/efeitos da radiação , Nanopartículas/efeitos da radiação
7.
Opt Express ; 17(18): 15623-34, 2009 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-19724561

RESUMO

A new approach is proposed for estimating the degree of coherence of optical waves. The possibility of transformation of the spatial polarization distribution in the measured spatial intensity distribution for determining the degree of correlation of superposing waves, linearly polarized in the plane of incidence, is shown.

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