1,720,978 research outputs found
Multiple scattering by two PEC sphere
Get PDFAn analysis of multiple scattering by two Perfect Electric Conducting (PEC) sphere using translation Addition Theorem (AT) for spherical vector wave equation is presented. Specifically, Cruzan formalism is used to represent the AT for spherical harmonics, which introduced translation coefficients for transformation of spherical harmonic from one coordinate to another. These coefficients allow a very efficient solution for the calculation of multiple scattering electric field using two PEC sphere in a near zone region. The numerical simulations are included the validity of the multiple scattering behavior
Mueller matrix polarimetry for differentiating characteristic features of different materials (wood, shinning steel, unpolished plastic)
Get PDFPolarization measurements improve the imaging contrast by using various samples (wood,shinning steel,unpolished plastic). For better explanations of the micro and macro-structures and basic characteristics of the materials, we perform Mueller matrix imaging on various samples, expressed by the characteristic features of the 3×3 Mueller matrix elements. This research gives new ideas for various samples on the contrast mechanisms of Mueller matrix components, which can provide new diagnostic techniques for biomedical applications
Absorption and invisibility of a Transparent Radial Anisotropy (TRA) cylinder
Get PDFThis article presents the inspection of a Transparent Radially Anisotropic (TRA) cylinder with permittivity dyadic, in the electrostatic settings. The quasistatic polarizability of the TRA cylinder with the values and signs of permittivity components offering different interesting features, involving absorbance, anomalous losses, resonant singularities, invisibility. In this manuscript, we have a special focus on the electrostatic response of a circular cylinder with a certain condition of
anisotropic parameters. We study the stimulating behaviour of polarizability of a TRA cylinder in quadrant (plane geometry). We have also computed the TRA cylinder behavior as a cloak using suitable choices of the anisotropic parameters
Scattering from a cylindrical obstacle deeply buried beneath a planar non-integer dimensional dielectric slab using Kobayashi potential method
No full textMathematical formulation for the far-zone field scattered by a cylindrical obstacle deeply
buried beneath a planar dielectric slab has been presented. Method known as Kobayashi
potential method has been employed for this purpose and transverse electric uniform plane
wave has been used as a source of excitation. It has been assumed that dimension of space
within slab is non-integer in the direction normal to planar interfaces of the slab. Moreover,
it has also been assumed that distance of each interface of the slab from obstacle is very large
as compared to size of the obstacle. Due to this assumption scattered field after reflection
from the slab has no interaction with the obstacle and the situation has been called deeply
buried. Field pattern has also been obtained and compared with the published work
Interpreting Mueller matrix of anisotropic material
Get PDFThe polarization imaging methodology has evolved to accept increasingly complex parametric measurements. The Mueller matrix is now generally calculated using a polarimetry technique. In our manuscript, we study the anisotropic wood sample using polarization imaging techniques. Herein, We attempt to study the difference between wood horizontal and vertical fibers. We calculated 3×3 Mueller matrix elements, which can be used to described an intuitive overview of the anisotropic material characteristics. We interpreted experimental results of Mueller matrix coefficients in terms of a graphical representation
Scattering of an inhomogeneous wave impinging on parallel stratified cylinders
Get PDFThe interplay between an inhomogeneous plane wave and unlimited parallel stratified cylinders is presented. A meticulous theoretical approach is employed to show the relative electromagnetic interaction. The generalized Vector Cylinder Harmonics (VCH) expansion application is used for investigating the electromagnetic scattering by a series of stratified cylinders. he commonly named complex-angle formalism is used in the exact mathematical model to depict
the current scenario. This approach allows the obtaining of the superposition of the VCH and the Foldy-Lax Multiple Scattering Equations (FLMSE) for considering the effect of multi-scattering between the stratified cylinders
Effects of finite terms on the truncation error for the addition theorem of spherical vector wave functions
No full textA finite sum adopted for the translational Addition Theorem (AT) of the spherical vector wave functions is a key-point for addressing a well known concept regarding the classical electromagnetic scattering of an incoming wave across a generic dispositions of spheres. The AT is essential for the translation of the vector spherical wave function expressed with respect to a coordinates system toward a different reference. According to its general formulation, the dependence of the translation coefficients on the relative direction of displacement linking two distinct references is the core study to be addressed. The inherent analytical aspects have been intensively studied during the last decades, but the respective numerical encoding has been limited to few basic configurations which provided a partial validity of the theory with quite approximate solutions. In literature there are many authors reporting different sets of the vector translation coefficients, among which we mention those calculated by Stein, Cruzan and Mackowski as the most prominent of them. We have selected the Cruzan formulation of the vector translation coefficients for its structure based on the Wigner 3-j function. We have developed the criteria of truncating the inherent infinite series to achieve convergence with a finite version of the same, which leads to an extremely negligible error. The procedure relies on the different parameters of the geometrical system, such as the direction angles and norm of the displacement vector, the angular indexes of spherical wave vector function, the propagation constant, and so on. During our numerical tests, we have deeply investigated generic truncation errors and outlined a repeatable procedure to get an acceptable convergence.
Our method allows to calculate a suitable truncation limit which ensures acceptable results in terms of contained AT truncation errors and simultaneously a onvergent series able to efficiently reconstruct the generic displaced vector wave function. We are sure that our improved approach will help researchers in developing efficient codes for the problem of light scattering across general distributions of spheres
Scattering of Light from the Systemic Circulatory System
Get PDFThere are many factors of methodological origin that influence the measurement of optical properties of the entire circulatory system which consists of blood as the basic component. The basic idea of this review article is to provide the optical properties of the circulatory system with all those factors of influence that have been employed in biomedical optics for different applications. We begin with the available optical properties, i.e., absorption, scattering and, reduced scattering coefficient, in general for any tissue inside the human body and prominent scattering theories (e.g., light, X-rays, neutrons) that are helpful in this regard. We have reviewed and compiled already available formulas and their respective available data for different human tissues for these optical properties. Then we have descended to the blood composition and to different scattering techniques available in the literature to study scattering and light propagation inside blood. We have reviewed both computational and theoretical scattering techniques
To study the Mueller matrix polarimetry for the characterization of wood and Teflon flat samples
Get PDFIn our manuscript, we carry out the Mueller matrix polarimetry for the characterization of wood and polytetrafluoroethylene (PTFE) or Teflon flat samples. Polarization measurements allows to enhance the imaging contrast of the anisotropic wood (Horizontal (H) and Vertical (V)) superficial fibers tissues and isotropic material (Teflon). We study the polarization-sensitive parameters for better investigations of the micro- and macro- structural and optical properties of complex tissues. The polarization imaging methodology has evolved to accept increasingly complex parametric measurements. The Mueller matrix is now generally calculated using a polarimetry technique. Herein, we attempt to study the difference between wood H, wood V, and Teflon samples. We calculated 3×3 Mueller matrix, which can be used to describe an intuitive overview of the material characteristics. We have interpreted our experimental results of Mueller matrix coefficients in terms of graphical representation using two different approaches named MS1 and MS2. This study gives us a new idea on the contrast mechanisms of polarization-sensitive measurements for different samples wood H, wood V, and Teflon and may provide new and simple diagnostic techniques for biological applications
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