Spatial Fourier transform method of measuring acoustic reflection coefficients at oblique incidence

Transformation of Fresnel’s interface reflection and transmission coefficients between normal and oblique incidence

Mapping of Fresnel's interface reflection coefficients between normal and oblique incidence: results for the parallel and perpendicular polarizations at several angles of incidence.

The functions, w = f(z), that describe the transformation of Fresnel's reflection coefficients of parallel and perpendicularly polarized light between normal and oblique incidence, as well as their inverses, z = g(w), are studied in detail as conformal mappings between the complex z and w planes for angles of incidence of 15, 30, 45, 60, and 75 degrees . New nomograms are obtained for the deter...

Acoustic Seabed Classification using Fractional Fourier Transform

In this paper we present a time-frequency approach for acoustic seabed classification. Work reported is based on sonar data collected by the Volume Search Sonar (VSS), one of the five sonar systems in the AN/AQS-20. The Volume Search Sonar is a beamformed multibeam sonar system with 27 fore and 27 aft beams, covering almost the entire water volume (from above horizontal, through vertical, back ...

Fourier transform interferometer alignment method.

A rapid and convenient method has been developed to facilitate the alignment of the image-plane components of point-diffraction interferometers, including the phase-shifting point-diffraction interferometer. In real time, the Fourier transform of the detected image is used to calculate a pseudoimage of the electric field in the image plane of the test optic where thecritical alignment o f vario...

Bessel beam through a dielectric slab at oblique incidence: the case of total reflection

The oblique incidence of a Bessel beam on a dielectric slab with refractive index n1 surrounded by a medium of a refractive index n > n1 may be studied simply by expanding the Bessel beam into a set of plane waves forming the same angle θ0 with the axis of the beam. In the present paper we examine a Bessel beam that impinges at oblique incidence onto a layer in such a way that each plane-wave c...