Ion optics with electrostatic lenses is presented using the standard matrix formalism of magnetic ion optics. We introduce the paraxial ray equation which is appropriate to systems with rotational symmetry. The first-order solutions of the paraxial ray equation are derived. The resulting transport matrices can be used to study systems with acceleration tube lenses, aperture lenses, einzel lense...

We consider the reconstruction of obstacles inside a bounded domain filled with an incompressible fluid. Our method relies on special complex geometrical optics solutions for the stationary Stokes equation with a variable viscosity.

We construct complex geometrical optics solutions for the isotropic elasticity system concentrated near spheres. We then use these special solutions, called complex spherical waves, to identify inclusions embedded in an isotropic, inhomogeneous, elastic background.

We develop a reconstruction algorithm to determine penetrable obstacles inside a domain in the plane from acoustic measurements made on the boundary. This algorithm uses complex geometrical optics solutions to the Helmholtz equation with polynomial-type phase functions.

We have computed the light transport in a bre in the geometrical optics approximation. The aim of this study is to compare the performances of single and double clad bres and to outline possible improvements to bre design.

Simple procedures and formulas for tracing the characteristics of a spherical Gaussian beam through a train of lenses or mirrors are described which are analogous to those used in geometrical optics to trace repeated images through an optical train.

We survey some recent results on the reconstruction of discontinuities by boundary measurements for elasticity and related systems in two dimensions. Our main tool is a new type of complex geometrical optics solutions.

In this paper, a ray-tracing technique to predict the propagation channel parameters in indoor scenarios is presented. It is a deterministic technique, fully three-dimensional, based on geometrical optics (GO) and the uniform theory of diffraction (UTD). A model of plane facets is used for the geometrical description of the environment. The ray tracing is accelerated considerably by using the A...

Knowing the solution to Helmholtz equation in a narrow band, with a width of order wave length around a scatterer, we investigate the possibility to construct the wave fronts predicted by the asymptotic methods Geometrical Optics (GO) and Geometrical Theory of Diffraction (GTD). More specifically we show how to build a polynomial approximation of the asymptotic solution on a circle around the s...

The material tensor of linear response in electrodynamics is constructed out of products of two symmetric second rank tensor fields which in the approximation of geometrical optics and for uniaxial symmetry reduce to “optical” metrics, describing the phenomenon of birefringence. This representation is interpreted in the context of an underlying internal geometrical structure according to which ...