A new approach to the generalized optical cross-section theorem in electromagnetics

AbstractStarting with Maxwell’s equations, we derive the fundamental results of the Huygens-Fresnel-Kirchhoff and Rayleigh-Sommerfeld theories of scalar diffraction and scattering. These results are then extended to cover the case of vector electromagnetic fields. The famous Sommerfeld solution to the problem of diffraction from a perfectly conducting half-plane is elaborated. Far-field scattering of plane waves from obstacles is treated in some detail, and the well-known optical cross-section theorem, which relates the scattering cross-section of an obstacle to its forward scattering amplitude, is derived. Also examined is the case of scattering from mild inhomogeneities within an otherwise homogeneous medium, where, in the first Born approximation, a fairly simple formula is found to relate the far-field scattering amplitude to the host medium’s optical properties. The related problem of neutron scattering from ferromagnetic materials is treated in the final section of the paper.

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A new theory of the generalized optical cross-section theorem for electromagnetic fields

2009 IEEE Antennas and Propagation Society International Symposium ◽

10.1109/aps.2009.5171765 ◽

2009 ◽

Cited By ~ 1

Author(s):

Edwin A. Marengo

Keyword(s):

Electromagnetic Fields ◽

Cross Section ◽

Optical Cross Section ◽

Section Theorem

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The optical cross-section theorem with incident fields containing evanescent components

Journal of Modern Optics ◽

10.1080/09500349908231311 ◽

1999 ◽

Vol 46 (5) ◽

pp. 891-899 ◽

Cited By ~ 15

Author(s):

P. Scott Carney

Keyword(s):

Cross Section ◽

Optical Cross Section ◽

Section Theorem

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A matrix model based on the optical cross section theorem for analyzing the scattering of nanoparticles

2014 Third Conference on Millimeter-Wave and Terahertz Technologies (MMWATT) ◽

10.1109/mmwatt.2014.7057208 ◽

2014 ◽

Author(s):

Fahimeh Armin ◽

Mir Mojtaba Mirsalehi

Keyword(s):

Cross Section ◽

Matrix Model ◽

Model Based ◽

Optical Cross Section ◽

Section Theorem

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A New Approach to the Demonstration of Oxidase-Localization Using Tannic Acid Or Catechin

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100073933 ◽

1973 ◽

Vol 31 ◽

pp. 698-699

Author(s):

V. Mizuhira ◽

Y. Futaesaku

Keyword(s):

Cross Section ◽

Tannic Acid ◽

Elastic Fiber ◽

The Other ◽

New Approach ◽

Tissue Block ◽

Active Reaction ◽

The Cross

Previously we reported that tannic acid is a very effective fixative for proteins including polypeptides. Especially, in the cross section of microtubules, thirteen submits in A-tubule and eleven in B-tubule could be observed very clearly. An elastic fiber could be demonstrated very clearly, as an electron opaque, homogeneous fiber. However, tannic acid did not penetrate into the deep portion of the tissue-block. So we tried Catechin. This shows almost the same chemical natures as that of proteins, as tannic acid. Moreover, we thought that catechin should have two active-reaction sites, one is phenol,and the other is catechole. Catechole site should react with osmium, to make Os- black. Phenol-site should react with peroxidase existing perhydroxide.

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New Method for Analysis of the Temporomandibular Joint Using Cone Beam Computed Tomography

Sensors ◽

10.3390/s21093070 ◽

2021 ◽

Vol 21 (9) ◽

pp. 3070

Author(s):

Sebastian Iwaszenko ◽

Jakub Munk ◽

Stefan Baron ◽

Adam Smoliński

Keyword(s):

Computed Tomography ◽

Temporomandibular Joint ◽

Cross Section ◽

Cone Beam Computed Tomography ◽

Cone Beam ◽

Section Plane ◽

New Approach ◽

Volume Of Interest ◽

Gap Width

Modern dentistry commonly uses a variety of imaging methods to support diagnosis and treatment. Among them, cone beam computed tomography (CBCT) is particularly useful in presenting head structures, such as the temporomandibular joint (TMJ). The determination of the morphology of the joint is an important part of the diagnosis as well as the monitoring of the treatment results. It can be accomplished by measurement of the TMJ gap width at three selected places, taken at a specific cross-section. This study presents a new approach to these measurements. First, the CBCT images are denoised using curvilinear methods, and the volume of interest is determined. Then, the orientation of the vertical cross-section plane is computed based on segmented axial sections of the TMJ head. Finally, the cross-section plane is used to determine the standardized locations, at which the width of the gap between condyle and fossa is measured. The elaborated method was tested on selected TMJ CBCT scans with satisfactory results. The proposed solution lays the basis for the development of an autonomous method of TMJ index identification.

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