Patent ID: 6278656
Filing Date: 2001-08-21
Classification: G10K

Abstract:
A device for manipulation of acoustic waves comprising a functionally-graded material for interposing between a source of said acoustic waves and a target for acoustic waves, said material having a gradient in acoustic wave velocity that is perpendicular to a direction of said acoustic waves wherein either (a) said material comprises a slab having said gradient from a first major surface to a second, opposite major surface, said first major surface and said second major surface defined by planes parallel to said direction of propagation, said gradient having a relatively high value in said acoustic wave velocity at one said major surface and a relatively low value in said acoustic wave velocity at said opposite major surface, said acoustic waves being steered toward said relatively low value of acoustic wave velocity or (b) said material comprises a slab having a gradient from a first major surface to a central region in said slab and from said central region to a second, opposite major surface, said first major surface and said second major surface defined by planes parallel to said direction of propagation, said gradient having a first value in said acoustic wave velocity at said first major surface and at said second major surface and a second, different value in said acoustic wave velocity in said central region and wherein said manipulated sonic waves are focused, dispersed, steered, or waveguided.