Abstract: A generally cylindrical hydrophone configuration provides compensation for longitudinal accelerations by placing four identical solid piezoelectric transducer elements along its axis with each transducer element being bonded to a head member, two of which are located generally centrally of the cylindrical housing and fastened thereto and two of which are located near the outside edges of the housing and having slight clearance therewith. Flexible polyurethane boots are clamped to the ends of the housing. The volumes between the centrally disposed and outer transducer head members and between the outer head members and the boots are filled with methyl silicon fluid. Each head member is electrically connected to one side of the electrical output, and the junction between the transducer members is connected to the opposite side, both sides being wired to an electrical contact plate located between the two centrally disposed transducer head members, this volume being filled with electrical potting material.

Abstract: A system having improved localization and wave generation apparatus for treatment of an area in the body of a patient. The system comprises a prelocation system allowing for initial localization of an area within a body of a patient. Following the initial localization step, the patient is moved into a treatment position using a sliding table top. A high power wave generation device is provided for generating waves for treating the area. The system further provides for an ultrasonic monitoring device, coupled with the high power wave generation device, allowing for real-time localization of the area. The disclosed system utilizes, as part of the wave generation device, a piezoelectric transducer, an acoustical lens coupled with the transducer and a means for coupling the transducer to receive voltage from a high power voltage means.

Abstract: An acoustical lens for focusing ultrasonic energy having a transducer, a curved focussing lens and a voltage generator coupled with the transducer. The transducer is comprised of an array of piezoelectric crystal elements. The focussing lens has a concave upper surface and a planar bottom surface allowing the array of piezoelectric elements to be coupled to the bottom surface of the array. The piezoelectric elements receive voltage from the voltage generator and transmit an energy ray through the focussing lens producing a focussed energy beam.

Abstract: A lithotripsy system having improved localization and shock wave generation apparatus. The lithotripsy system comprises an x-ray prelocation system allowing for initial localization of a calulus within a body of a patient. Following the initial localization step, the patient is moved utilizing a sliding table top into a treatment position. A high power shock-wave generation device is provided for generating shock waves for disintegrating the calculus. The lithotripsy system further provides for an ultrasonic monitoring device, coupled with the high power shock wave generation device, allowing for real-time localization of the calculi. The disclosed system utilizes, as part of the shock wave generation device, a piezoelectric transducer, an acoustical lens coupled with the transducer and a means for coupling the transducer to receive voltage from a high power voltage means.

Abstract: An acoustical lens for focusing ultrasonic energy having a transducer, a curved focussing lens and a voltage generator coupled with the transducer. The transducer is comprised of an array of piezoelectric crystal elements. The focussing lens has a concave upper surface and a planar bottom surface allowing the array of piezoelectric elements to be coupled to the bottomsurface of the array. The piezoelectric elements receive voltage from the voltage generator and transmit an energy ray through the focussing lens producing a focussed energy beam.

Abstract: A pulsed power supply for providing power to a piezoelectric crystal. The power supply provides power to the piezoelectric crystal causing contraction of the crystal. Upon reaching a predetermined degree of contraction, the electrical voltage form the power supply is removed from the piezoelectric crystal by creating a short-circuit between the power supply and the crystal. Removal of electrical voltage from the crystal causes the immediate expansion of the crystal and a resulting energy wave.

Abstract: A impedance matching window for an ultrasound transducer comprises a periodic array of stepped structures. Each stepped structure comprises a plurality of parallel matching strips disposed side-by-side on an active surface of a piezoelectric ceramic.

Abstract: A hydrophone configuration provides compensation for longitudinal accelerations by placing two essentially identical solid ceramic piezoelectric elements back-to-back against a centrally located bulkhead in a strong cylindrical metal housing. The opposite ends of the elements are bonded to end caps which are mechanically sealed to the inside walls of the housing. The inside walls are spaced from the elements to allow any radial expansion or contraction of the elements to take place into an air chamber which is effectively isolated from the input to the hydrophone which is axial against the outside surfaces of the end caps. In a second embodiment two pairs of parallel-connected piezoelectric elements are included for a higher capacitance.