A conventional spherical acoustic lens is modified by restricting its aperture in the form of a slit to provide directional sensitivity. The spacing between the two parallel absorbing sheets forming the slit is adjustable ...

The Lamb wave lens is a type of lens that can replace the conventional lens of an acoustic microscope for some applications. When it insonifies a layered solid structure, it excites a single mode in the structure, provided ...

A new directional acoustic lens is introduced. The geometry is very similar to the line-focus lens except the lens cavity, which is shaped as a groove with flat-bottom V cross section. The slanted planar edges of the groove ...

Axicons are generators of waves which focus on a line. They are used in various imaging and nondestructive testing applications as bulk wave focusing devices with a very long depth of focus. In this letter, a new type of ...

The Lamb wave and V-groove lenses are distinguished by their high surface wave excitation efficiencies. However, due to the fixed incidence angle, a particular lens can only be used for materials having surface wave ...

In this paper a new lens design is proposed for characterization of layered materials. Lamb wave lens employs Lamb waves for this purpose since these waves propagate along interfaces. However, below cut-off angle, the ...

Lamb wave lenses with conical refracting surfaces are fabricated for use at 400 MHz and 1 GHz. The conical surfaces are ground and polished with mechanical means and they are sufficiently smooth for the frequencies of ...

In a conventional scanning acoustic microscope the excited leaky modes contributes significantly to the high contrast obtained in the images. However, all such modes exist simultaneously, and the interpretation of the ...