The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 12, 1992
Filed:
Aug. 28, 1990
Peter Jaggy, Otisheim, DE;
Werner Krauss, Knittlingen, DE;
Dagobert Schafer, Bretten, DE;
Helmut Wurster, Oberderdingen, DE;
Richard Wolf GmbH, Knittlingen, DE;
Abstract
There is disclosed, a piezoelectric transducer for generating focussed ultrasonic shock waves for use in lithotripsy. The ultrasonic shock waves are emitted in pulsed form and can be transmitted by way of a coupling medium to the body of a patient to be treated. The transducer comprises a substantial member of individual piezoelectric transducer elements of ceramic or like material which are connected to the poles of a pulse generator and are fixed to a support in mosaic form and with their sides electrically insulated from one another. The acoustic termination of the transducer elements is essentially free from reflection. An intermediate medium of at least one layer, the acoustic impedance of which lies between that of the ceramic of the transducer element and that of the coupling medium, is provided between the transducer elements and the coupling medium. The thickness d of the layer is chosen in accordance with the relationship d>.tau..sub.k .multidot.c.sub.LA, where .tau..sub.k is the propagation time of sound in the piezoceramic of the transducer elements and c.sub.LA is the sound velocity in the intermediate medium.