Ultrasound transducers with improved focus in the elevation direction

摘要

A phased array ultrasound transducer is made from a plurality of independently excitable elements that are arranged in a row in the azimuthal direction, configured so that azimuthal aiming of an outgoing ultrasound beam is controlled by timing the excitation of the elements. The geometry of the elements is configured to focus the outgoing beam in the elevation direction so as to improve the images of target regions located at or about a particular radial distance. In some embodiments, this is accomplished by forming each element from a plurality of subelements that are stacked in the elevation direction, with the subelements of any given element all (a) wired together and (b) positioned at about the same distance from a substantially rod-shaped focal region.