Patent ID: 6467140
Filing Date: 2002-10-22
Classification: B06B,H01L,H04R,Y10T

Abstract:
A method of making a medical ultrasound transducer element having an acoustical impedance substantially matching the acoustical impedance of the body, and an electrical impedance for efficient power transfer with an ultrasound imaging system, the method comprising:preparing a 2â€”2 or 1-3 composite transducer element for driving in a k31 transverse mode, the element having a plurality of relatively thin spaced piezoelectric wafers having relatively large area opposing major surfaces; providing electrodes on the major surfaces for electrically connecting the wafers in parallel, wherein each of opposing sets of electrodes extend from a different one opposing end of the wafer to a distance spaced from the other end of the wafer; providing a layer of passive polymer between the electrodes on adjacent wafers, which polymer is selected to provide an acoustic impedance substantially similar to the acoustic impedance of the body; and selecting a number of the spaced piezoelectric wafers to provide a transducer element having a reduced electrical impedance for improved power transfer with the imaging system.