Imperfections Influence Modeling upon Eigenvibrations in a Convex Piezoelectric Plate of AT-cut

A discrepancy is analyzed between the measurements and predictions of the amplitude distributions of eigenvibrations in a trapped-energy convex piezoelectric plate of thickness-shear vibrations that is in the rotation of a measured picture of the amplitude distribution regarding the plate axes, unlike the strongly symmetric case associated with a spherical surface. Such a rotation is neatly seen in the measurements obtained by a highly sensitive laser speckle method. We show that a possible source of the asymmetry and displacements is in the imperfections of a convex surface of a manufactured plate.