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 ...

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 ...