Integrated grating acoustic scanner

Abstract

This letter describes a new type of electronically scanned and focused acoustic imaging device called the integrated grating acoustic scanner. In this device, a nonlinear chirped surface acoustic wave pulse expansion/compression filter and an array of grooves were integrated on the same piece of piezoelectric single-crystal plate. The periodical grooves scattered a chirped surface-wave pulse coherently into a focused bulk-wave spot, which scans at the surface-wave velocity. A 150-MHz integrated LiNbO3 grating scanner with 1-cm field of view and 40-μm resolution has been constructed and studied.