Abstract: A method and apparatus for apodization is exemplified in an ultrasound transducer used, for example, in medical applications. The method and apparatus of the present invention provides an ultrasonic transducer with frequency and amplitude apodization, thus improving signal quality and producing improved ultrasonic images. The manufacture of this apparatus is improved by the making of composite cuts into piezoelectric material according to a predetermined pattern which generally varies the concentration of piezoelectric material across the surface of the transducer. Concentration of piezoelectric material can be varied across the surface of the piezoelectric transducer by varying the spacing between the cuts in the piezoelectric material, or by varying the width of the cuts in the piezoelectric material, or a combination of both.

Abstract: A transducer is tuned to a desired impedance by building piezoelectric assemblies of multiple layers, each layer acting as a parallel capacitor. Piezoelectric layers are preferably constructed by plating or otherwise placing a conducting perimeter around a piezoelectric substrate. Gaps are suitably formed in the conducting layer by dicing or otherwise to form distinct electrical conducting regions on each layer. Piezoelectric layers are then suitably placed such that positive and negative conducting regions on each layer contact positive and negative regions on other layers. Layers are suitably joined by epoxy or by any other joining technique.

Abstract: A transducer is tuned to a desired impedance by building piezoelectric assemblies of multiple layers, each layer acting as a parallel capacitor. Piezoelectric layers are preferably constructed by plating or otherwise placing a conducting perimeter around a piezoelectric substrate. Gaps are suitably formed in the conducting layer by dicing or otherwise to form distinct electrical conducting regions on each layer. Piezoelectric layers are then suitably placed such that positive and negative conducting regions on each layer contact positive and negative regions on other layers. Layers are suitably joined by epoxy or by any other joining technique.

Abstract: An ultrasonic transducer array, and a method for manufacturing it, having a plurality of transducer elements aligned along an array axis in an imaging plane. Each transducer element includes a piezoelectric layer and one or more acoustic matching layers. The piezoelectric layer has a concave front surface overlayed by a front electrode and a rear surface overlayed by a rear electrode. The shape of each transducer element is selected such that it is mechanically focused into the imaging plane. A backing support holds the plurality of transducer elements in a predetermined relationship along the array axis such that each element is mechanically focused in the imaging plane.

Abstract: An ultrasonic transducer array having a plurality of transducer elements aligned along an array axis in an imaging plane. Each transducer element includes a piezoelectric layer and one or more acoustic matching layers. The piezoelectric layer has a concave front surface overlayed by a front electrode and a rear surface overlayed by a rear electrode. The shape of each transducer element is selected such that it is mechanically focused into the imaging plane. A backing support holds the plurality of transducer elements in a predetermined relationship along the array axis such that each element is mechanically focused in the imaging plane.

Abstract: An ultrasonic transducer array having a plurality of transducer elements aligned along an array axis in an imaging plane. Each transducer element includes a piezoelectric substrate and further includes a rear electrode applied to the substrate's rear surface and a patterned front electrode applied to the substrate's front surface. A conductive or metalized acoustic matching layer overlays the patterned front electrode. The front electrode is specially patterned along an elevation axis perpendicular to the imaging plane, so as to apodize the emitted ultrasonic beam in the elevation plane. The pattern follows a predetermined tapered weighting function, preferably one that approximates a Hamming weighting function. Slots, oriented parallel with the array axis, are cut into the piezoelectric substrate's front surface, to form a plurality of subelements. This further isolates these portions of the piezoelectric substrate not overlaid by the patterned front electrode, thereby enhancing beam apodization.