Imaging devices having piezoelectric transceivers with harmonic characteristics

A micromachined ultrasonic transducer (MUT), comprising:

• a plurality of piezoelectric layers comprising M piezoelectric layers;
• a plurality of electrodes comprising N electrodes,
• wherein a piezoelectric layer of the plurality of piezoelectric layers with an index m is disposed between a first electrode with an index m and a second electrode with an index m+1, wherein the index m is associated with a vertical distance of the piezoelectric layer;
• when seen in a top view, at least the first electrode having first and second ends along a first axis,
• i. wherein one or more of the first end or second end is defined by a radius of curvature R,
• ii. wherein a second axis passes through a midpoint of the first axis, wherein the second axis is normal to the first axis,
• iii. wherein a half-width of the first electrode is defined by a length L measured from the midpoint, in the direction of the second axis, to an outer perimeter of the first electrode,
• iv. wherein a total width of the first electrode at its widest point along the first axis is at least two times L such that the first electrode has a convex shape, and
• v. wherein R/L is less than 1.