Apple Inc.
Shear-poled curved piezoelectric material

Abstract:

Acoustic transducers can be formed form piezoelectric materials including one or more curved (non-linear) segments. The piezoelectric material can be shear poled such that a poling direction of the piezoelectric material can follow the curvature of the piezoelectric material. The piezoelectric material can also have a unidirectional poling direction. In some examples, the piezoelectric material can be a closed ring with a circular or partially circular shape. A shear poling process for a piezoelectric material with curves can include shear poling segments of the piezoelectric material with one or more sets of poling electrodes. The poling electrodes of a respective one of the one or more sets of poling electrodes can be coupled to the same side of the piezoelectric material.