Two original approaches for the diagnostics of phase singularities (such as optical vortices, screw dislocations of a wave
front) based on the Young-Rubinowicz mOdel of diffraction phenomena are represented. Both techniques are implemented
without using a separate reference wave, as in common interference techniques. That is why they are very convenient for
analysis of spatially coherent polychromatic fields. The first technique is based on the use of an opaque strip as the diffraction
device. Bending Young's interference fringes produced by the edge diffraction waves from two rims of the strip within
the geometrical shadow region reflect helicity of a wave front, so that the direction and magnitude of bending correspond
directly to the sign and the modulus of topological charge of the optical vortex, respectively. This technique is practicable
for diagnostics of isolated polychromatic vortices, such as "rainbow" Laguerre-Gaussian mode, where the condition of mutual
spectral purity is satisfied. Another technique is based on the use of knife-edge diffraction. The edge of an opaque
screen serves as the source of a reference wave, which interferes with the tested field within the directly illuminated region.
One observes typical interference forklets near the geometrical shadow boundary, which detect optical vortices. This technique
is more applicable to diagnostics of phase singularities in polychromatic speckle fields due to the condition of mutual spectral purity is satisfied automatically.
A simple method for creation of 'rainbow' polychromatic optical vortices using a point-like white-light source and the computer-generated hologram technique is reported. The conditions of spatial stability of long-distance propagating rainbow optical vortices are established, as well as the regularities governing the radial alternation of colors. The diffraction technique for revealing and diagnostics of vortices at partially coherent beam [Opt. Lett.28, 878, 2003] is for the first time applied to polychromatic beams supporting phase singularities.
Negative imaging of an extended source of polychromatic radiation by an opaque screen is described within the framework of geometrical optics. Spatial domain behind the screen is determined where a negative image is observed, as well as the main optical characteristics of such image. Digital post-processing procedure for improving of an optically obtained negative image is introduced and implemented.
Method of using the matrix method optics of light-scattering media for research the polarization characteristics of objects with dynamically varying geometrical optic parameters is described in this work. The results of measuring the Mueller matrix components of nematic liquid crystal (NLC) during the activity of electrical impulse are given. The character of transformation matrix (MT) and light scattering matrix (LSM) symmetry of exploring medium is determined. General analysis of nonzero components time dependencies of NLC Mueller matrix is given. The possibility of using the electro controllable liquid crystal as the model object for exploring the influence of the shape, size and orientation of nonspherical particles on the size of their Mueller matrix components is noted.
Method of using the matrix method optics of light-scattering media for research the polarization characteristics of objects with dynamically varying geometrical optic parameters is described in this work. The results of measurings the Mueller matrix components of nematic liquid crystal (NLC) during the activity of electrical impulse are given. The character of transformation matrix (MT) and light scattering matrix (LSM) symmetry of exploring medium are determined. General analysis of nonzero components time dependencies of NLC Mueller matrix is given. The possibility of using the electrocontrollable liquid crystal as the model object for exploring the influence of the shape, size and orientation of nonspherical particles on the size of their Mueller matrix components is noted.
The effect of negative imaging of an extended source of polychromatic radiation by an opaque screen is elaborated. It is shown that such imaging is of geometrical optics (shadow) nature rather than of diffraction one, as it was assumed earlier. On the base of the geometrical optics model, we define spatial domain behind an opaque screen where the negative imaging is realized, and determine the dependencies of the image parameters on the experimental conditions. Negative images are demonstrated for the first time, and the qualitative confirmation of the geometrical optics model is given.
Lately there is observed a considerable interest in studying the problems connected with the optimization of the structure and form of bones as biological constructions that cater for the necessary strength characteristics of the body as a whole and of different organs separately under the static and dynamic effect. The urgency of this investigation is conditioned, first and foremost, by the needs of medicine. The necessity of obtaining the results of this research arises when solving various problems connected with creating new technical and medicine composite materials on the basis of the structure of human compact bone tissue, prothesing of organs and tissues, etc.
The fractal nature of the majority of biological tissues and intensive development of laser diagnostics in biology and medicine are stimulated an interest to creation of new optical methods of diagnostics and analysis of properties of biological fractals.
The fractal nature of the majority of biological tissues and intensive development of laser diagnostics in biology and medicine are stimulate an interest to creation of new optical methods of diagnostics and analysis of properties of biological fractals. The present paper is dedicated to investigation of polarizational properties of cross layers of bone and muscle tissues.
The phase-polarized method of visualization of optical- anisotropy inhomogeneities of biotissues is proposed. It is based on the multifractal modeling of biotissue properties. The algorithm of receiving topograms of orientation of fractal domains of visualized architecture net of a biotissue is elaborated and approved experimentally.
The present paper deals with the research of laser radiation polarized structure, transformed by biotissue crystalline phase. It is urgent in creating optical methods of diagnostics of biotissue orientation and mineralized structure, and in modeling biocomposite materials as well.
Recently the photometric and spectrophotometric methods of biotissue diagnostics, based on searching interrelation of scalar characteristics of optical radiation field with their structural parameters. The complex of investigation of transformation processes of linear-polarized radiation in biotissues has demonstrated the new possibilities of diagnostics of their pathological biotissues (human skin derma, with whit matter and tissues of the gray matter, tissue of aorta side, necrotic ulcer, bone tissue, etc.). The report presented deals with researching possibilities of laser polarized diagnostics of arising and proceeding of pathological changes of biotissue morphological structure.
The fractal nature of the majority of biological tissues and intensive development of laser diagnostics in biology and medicine are stimulated an interest to creation of new optical methods of diagnostics and analysis of properties of biological fractals. The present paper is dedicated to investigation of polarizational properties of cross layers of bone and muscle tissues.
The fractal nature of the majority of biological tissues and intensive development of laser diagnostics in biology and medicine are stimulate an interest to creation of new optical methods of diagnostics and analysis of properties of biological fractals.
The author's results of the experimental research work of scattering of polarized radiation with a model system of isotropy and anisotropy oriented absorbing particles are reported. The experimental situations and characteristics of scattered radiation that are better to use under the diagnostics of the mentioned system are picked out.
Necessity of supersmooth optical radiation transparent surfaces and laser mirrors with minimum losses through scattering creation required the subsequent development of refiectometric nondestructive surface roughness measurement methods. There are the scalar theory of reflectivity from rough es' and the vector theory 2 have been worked out in the present time. The last of them takes in account interaction of the electromagnetic radiation with surface electrons and influence of the reflectivity material constants. There is the comparative analysis of the scattering light spatial distribution measurement methods given in this paper. The reflectivity radiation diffusion component is examined as a function of the statistical parameters root mean square (rms) surface roughness a, autocovariance length of the surface a and root mean square microfacet pitch tg y = a/a. There is the optical radiation transparent measurement method3 discussed in this work. The results of this measuring method for supersmooth surfaces were compared with theory and ones obtained with other methods and it was received good agreement. The connection of the scattering indicatrix with the parameters of the high quality laser mirrors has been described in this work. The methods which allow to measure back scattering and scattering "in mode" and influence this differential scattering to the interferometrical measurement devices parameters are discussed.
Physical principles underlying the original noncontact optical-correlation techniques for surface diagnostics are discussed. The performance of the optical correlation devices is compared with that of the available diagnostics systems. The proposed systems for surface diagnostics are based on the relationship between the statistical parameters of the object's structure and the associated correlation parameters of the scattered optical field. The relationship is used in developing diagnostic systems based on the scintillation index, the transverse correlation function, the amplitude variance and the field phase measurements '.The advantage of the proposed systems is the high speed (1.2 seconds) operation which is achieved by performing the statistical data processingwithin the optical channeL The height parameter measurement accuracy is 25 A.
Experimental results on energy and polarization characteristics of the radiation reflected by a layer containing oriented particles are presented. Two models of surface layer are considered: isotropically absorbing particles (model 1), and anisotropically absorbing particles (model 2). Model 1 refers to a layer containing (gamma) -Fe2O3 particles with different orientations. Estimates of the particle orientation degree were made from the photomicrographs taken at 1030x magnification. Model 2 refers to a polaroid film containing fully oriented (B equals 0.99) needle-like herapathite microcrystals.
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