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Full-Text Articles in Physics
Far-Field Scattering Of A Non-Gaussian Off-Axis Axisymmetric Laser Beam By A Spherical Particle, James A. Lock, Joseph T. Hodges
Far-Field Scattering Of A Non-Gaussian Off-Axis Axisymmetric Laser Beam By A Spherical Particle, James A. Lock, Joseph T. Hodges
Physics Faculty Publications
Experimental laser beam profiles often deviate somewhat from the ideal Gaussian shape of the axisymmetric TEM(00) laser mode. To take these deviations into account when calculating light scattering of an off-axis beam by a spherical particle, we use our phase-modeling method to approximate the beam-shape coefficients in the partial wave expansion of an experimental laser beam. We then use these beam-shape coefficients to compute the near-forward direction scattering of the off-axis beam by the particle. Our results are compared with laboratory data, and we give a physical interpretation of the various features observed in the angular scattering patterns. (C) 1996 …
An Exactly Soluble Fresnel Diffraction Model Of Two-Slit Interference, James A. Lock
An Exactly Soluble Fresnel Diffraction Model Of Two-Slit Interference, James A. Lock
Physics Faculty Publications
Using the formalism of Fresnel diffraction, we examine the diffraction and interference of two initially widely separated parallel Gaussian light beams. This two-beam configuration is a version of Young's two-slit interference problem that is free of the mathematical complexity that occurs in most Fresnel diffraction calculations. As a result, it clearly and simply illustrates the transition from ray optics to wave interference. (C) 1996 American Association of Physics Teachers.
Far-Field Scattering Of An Axisymmetric Laser Beam Of Arbitrary Profile By An On-Axis Spherical Particle, James A. Lock, Joseph T. Hodges
Far-Field Scattering Of An Axisymmetric Laser Beam Of Arbitrary Profile By An On-Axis Spherical Particle, James A. Lock, Joseph T. Hodges
Physics Faculty Publications
Experimental laser beam profiles often deviate somewhat from the ideal Gaussian shape of the TEM(00) laser mode. In order to take these deviations into account when calculating light scattering, we propose a method for approximating the beam shape coefficients in the partial wave expansion of an experimental laser beam. We then compute scattering by a single dielectric spherical particle placed on the beam's axis using this method and compare our results to laboratory data. Our model calculations fit the laboratory data well. (C) 1996 Optical Society of America
Ray Scattering By An Arbitrarily Oriented Spheroid .Ii. Transmission And Cross-Polarization Effects, James A. Lock
Ray Scattering By An Arbitrarily Oriented Spheroid .Ii. Transmission And Cross-Polarization Effects, James A. Lock
Physics Faculty Publications
Transmission of an arbitrarily polarized plane wave by an arbitrarily oriented spheroid in the short-wavelength limit is considered in the context of ray theory. The transmitted electric field is added to the diffracted plus reflected ray-theory electric field that was previously derived to obtain an approximation to the far-zone scattered intensity in the forward hemisphere. Two different types of cross-polarization effects are found. These are (a) a rotation of the polarization state of the transmitted rays from when they are referenced with respect to their entrance into the spheroid to when they are referenced with respect to their exit from …
Ray Scattering By An Arbitrarily Oriented Spheroid .I. Diffraction And Specular Reflection, James A. Lock
Ray Scattering By An Arbitrarily Oriented Spheroid .I. Diffraction And Specular Reflection, James A. Lock
Physics Faculty Publications
Diffraction and reflection of an arbitrarily polarized plane wave by an arbitrarily oriented spheroid in the short-wavelength limit are considered in the context of ray theory. A closed-form solution for both diffraction and reflection is obtained, and the polarization character of the diffracted plus reflected electric field is obtained. It is found that the magnitude of the reflected electric field is multivalued for forward scattering. This is interpreted in terms of the variation of the spheroid's Gaussian curvature at the points where grazing ray incidence occurs.