EP0436809A2 - Ultrasonic transducer using piezoelectric elements - Google Patents

Ultrasonic transducer using piezoelectric elements Download PDF

Info

Publication number
EP0436809A2
EP0436809A2 EP90122050A EP90122050A EP0436809A2 EP 0436809 A2 EP0436809 A2 EP 0436809A2 EP 90122050 A EP90122050 A EP 90122050A EP 90122050 A EP90122050 A EP 90122050A EP 0436809 A2 EP0436809 A2 EP 0436809A2
Authority
EP
European Patent Office
Prior art keywords
electrodes
transducer elements
transducer
ultrasonic transducer
figures
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP90122050A
Other languages
German (de)
French (fr)
Other versions
EP0436809A3 (en
Inventor
Dagobert Dipl.-Ing. Schäfer
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Richard Wolf GmbH
Original Assignee
Richard Wolf GmbH
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Richard Wolf GmbH filed Critical Richard Wolf GmbH
Publication of EP0436809A2 publication Critical patent/EP0436809A2/en
Publication of EP0436809A3 publication Critical patent/EP0436809A3/en
Withdrawn legal-status Critical Current

Links

Images

Classifications

    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/002—Devices for damping, suppressing, obstructing or conducting sound in acoustic devices
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B06—GENERATING OR TRANSMITTING MECHANICAL VIBRATIONS IN GENERAL
    • B06B—METHODS OR APPARATUS FOR GENERATING OR TRANSMITTING MECHANICAL VIBRATIONS OF INFRASONIC, SONIC, OR ULTRASONIC FREQUENCY, e.g. FOR PERFORMING MECHANICAL WORK IN GENERAL
    • B06B1/00—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency
    • B06B1/02—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy
    • B06B1/06—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy operating with piezoelectric effect or with electrostriction
    • B06B1/0607—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy operating with piezoelectric effect or with electrostriction using multiple elements
    • B06B1/0622—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy operating with piezoelectric effect or with electrostriction using multiple elements on one surface
    • B06B1/0637—Spherical array

Definitions

  • the invention relates to an ultrasound transducer for lithotripsy, in which piezoelectric transducer elements are fastened to a carrier and are connected on the front side to first electrodes and on the rear side to second electrodes which can be connected to an electrical pulse generator in order to generate electrical fields in pulses in the transducer elements via the electrodes and make them vibrate.
  • Ultrasonic transducers designed in this way are known. Their mode of operation is based on the fact that when a voltage is applied, the piezoceramic transducer element in the interior is suddenly produced a mechanical stress state which arises from the fact that an electrical field builds up in the interior of the transducer element, which causes every layer of the transducer element endeavors to change its thickness. If the electrodes of the ceramic bodies of the transducer elements are parallel, a homogeneous electric field is generated inside them, which generates transducer elements with negative signs in addition to positive pressure pulses when the transducer elements are attached to a reflection-free backing (backing). These appear as pulling impulses, which in particular with the usual focusing transducers entail the risk of tissue damage in the focus environment.
  • DE-PS 34 25 992 shows a piezoelectric transducer in which a plurality of transducer elements are arranged on the front of a spherical cap-shaped carrier.
  • the dome material is selected so that its wave resistance hardly differs from that of the ceramic elements and the back of the surface of the dome is designed in such a way that the sound waves reflected on it, generated by the ceramic elements, are not focused. This allows a favorable ratio of the amplitudes of the achieve positive and negative pulses, but a desired further reduction of the negative pulses cannot be achieved, since their shape at the transducer element carrier interface is predetermined by the existing geometry of the transducer elements and the electrode arrangement.
  • DE-OS 31 19 295 shows a further device for destroying concrements, in which the risk of tissue damage is reduced by the fact that the ultrasound transducer to be focused on the concretion is so large that on the one hand, the sound power density on the transmission path is small, but on the other hand the focus is so large that it is sufficient to destroy the concretion in focus.
  • the electrodes are designed and arranged in such a way that a homogeneous field can be generated in the region of one end of the transducer elements and an inhomogeneous field in the opposite region of the transducer elements.
  • the second electrodes have an at least partially different shape from the first electrodes and specifically in that the second, cup-shaped electrodes each completely enclose one area of the transducer elements.
  • This measure increases the amplitude of the positive pressure pulse, while at the same time reducing that of the negative pressure pulse and increasing its duration.
  • the result is opposite behavior when the positive and negative pressure pulses are generated, the duration multiplied by the square of the amplitude being a measure of the energy density contained in the respective pressure pulse.
  • the bottom of the cup-shaped second electrodes can run parallel to the first electrodes.
  • the second electrodes can also be designed in the form of rings which lie on the same axis as the transducer elements assigned to them and each surround the rear part of the transducer elements.
  • the electrical connection can be made on the rear side in that the rear end surfaces of the transducer elements and the rings are connected in an electrically conductive manner to the likewise conductive carrier.
  • Another possibility of the rear electrical connection is that the second electrodes are formed by recesses in the electrically conductive carrier and that the electrodes with their rear parts are fixed in the recesses.
  • the electrical connection of the transducer elements at the front can take place in that the front ends of the transducer elements are covered together with an electrical conductor forming the first electrodes.
  • FIG. 1 shows a focusing ultrasound transducer 1 which has a multiplicity of piezoelectric ultrasound transducer elements 2 in a ring arrangement around the central axis.
  • the ultrasound transducer 1 is designed in the shape of a spherical cap and is therefore mechanically focused and, moreover, can be electronically focused in a known and therefore not to be described in detail.
  • the transducer elements 2 are fastened according to FIG. 2 with their rear ends to an electrically conductive carrier 3, which has a dome-shaped basic shape, preferably by gluing.
  • Each converter element 2 as can be seen better in FIG. 3, is bordered at its rear end by a cup-shaped electrode 4, so that it forms the contact with the electrically conductive carrier 3. This contact is ensured by using an electrically conductive adhesive.
  • the cup-shaped design of the electrode 4 has the effect that not only the flat end face of the transducer elements 2 is electrically conductively connected, but also parts of the lateral boundary surfaces thereof. This fact has the effect that when a voltage is applied between a front electrode 5 and the rear cup-shaped electrodes 4, an electrical field as indicated in FIG.
  • the front electrode 5 can be provided in the form of an electrically conductive film to which the front faces of the transducer elements 2 are connected.
  • the structure of the ultrasound transducer 1 according to FIG. 4 provides that the transducer elements 2 are attached with their front faces to a plate 6 that conducts sound energy and is electrically conductive, and the cup-shaped electrodes 4 attached to the back of the transducer elements 2 are individually electrically conductively connected to one another .
  • the transducer elements 2 designed according to the invention are fastened with their rear ends, bordered by cup-shaped electrodes 4, to a flat support surface and, according to FIG. 6, are fitted into a recess 7 in the support 3, thus giving the cup-shaped configuration of the electrode 4. 7, a conical recess 8 is provided, which likewise causes an inhomogeneity of the electrical field in the region of the rear end of the transducer element 2.
  • the pulse-wise electrical impingement of the transducer elements 2 takes place in a known manner by means of a pulse generator 9, the poles of which are connected on the one hand to the carrier 3 and on the other hand to the film connecting the front ends of the transducer elements 2.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Acoustics & Sound (AREA)
  • Multimedia (AREA)
  • Transducers For Ultrasonic Waves (AREA)
  • Surgical Instruments (AREA)
  • Ultra Sonic Daignosis Equipment (AREA)

Abstract

Es ist ein Ultraschallwandler (1) für die Lithotripsie beschrieben, bei dem piezoelektrische Wandlerelemente (2) an einem Träger (3) befestigt sind und frontseitig mit ersten sowie rückseitig mit zwei Elektroden (4,5) verbunden sind, die an einen elektrischen Impulsgenerator (9) anschließbar sind. Um insbesondere bei fokussierenden Wandlern die Gefahr von Gewebeschädigungen im Fokusumfeld zu vermeiden, sind die Elektroden (4,5) so ausgebildet, daß im frontseitigen Teil der Wandlerelemente (2) ein homogenes Feld und im gegenüberliegenden, rückseitigen Teil der Wandlerelemente (2) ein inhomogenes Feld erzeugt wird. Dadurch wird die Amplitude des neben dem positiven Druckpuls auftretenden negativen Pulses reduziert, welch letzterer für die Gefahr dieser Gewebeschädigungen verantwortlich ist. Um diesen Effekt zu erreichen, ist jedes Wandlerelement (2) mit einer topfförmigen Elektrode (4,5) versehen, die den rückseitigen Teil des Wandlerelementes (2) einschließt. <IMAGE>An ultrasound transducer (1) for lithotripsy is described, in which piezoelectric transducer elements (2) are fastened to a carrier (3) and are connected on the front to first electrodes and on the back with two electrodes (4, 5) which are connected to an electrical pulse generator ( 9) can be connected. In order to avoid the risk of tissue damage in the focus area, in particular in the case of focusing transducers, the electrodes (4, 5) are designed such that a homogeneous field in the front part of the transducer elements (2) and an inhomogeneous one in the opposite, rear part of the transducer elements (2) Field is generated. This reduces the amplitude of the negative pulse occurring alongside the positive pressure pulse, the latter being responsible for the risk of this tissue damage. In order to achieve this effect, each transducer element (2) is provided with a cup-shaped electrode (4, 5) which encloses the rear part of the transducer element (2). <IMAGE>

Description

Die Erfindung betrifft einen Ultraschallwandler für die Lithotripsie, bei dem piezoelektrische Wandlerelemente an einem Träger befestigt sind und frontseitig mit ersten sowie rückseitig mit zweiten Elektroden verbunden sind, die an einen elektrischen Impulsgenerator anschließbar sind, um über die Elektroden impulsweise elektrische Felder in den Wandlerelementen zu erzeugen und diese zum Schwingen anzuregen.The invention relates to an ultrasound transducer for lithotripsy, in which piezoelectric transducer elements are fastened to a carrier and are connected on the front side to first electrodes and on the rear side to second electrodes which can be connected to an electrical pulse generator in order to generate electrical fields in pulses in the transducer elements via the electrodes and make them vibrate.

Derartig konzipierte Ultraschallwandler sind bekannt.Ihre Wirkungsweise beruht darauf, daß bei Anlegen einer Spannung das piezokeramische Wandlerelement im Innern desselben schlagartig ein mechanischer Spannungszustand erzeugt wird, der dadurch entsteht, daß sich im Innern des Wandlerelementes ein elektrisches Feld aufbaut, das bewirkt, daß jede Schicht des Wandlerelementes das Bestreben hat, ihre Dicke zu ändern. Bei Planparallelität der Elektroden der Keramikkörper der Wandlerelemente entsteht dabei im Innern derselben ein homogenes elektrisches Feld, das bei auf einem reflexionsfreien rückseitigen Träger (backing) befestigten Wandlerelementen neben positiven Druckpulsen auch Druckpulse mit negativen Vorzeichen erzeugt. Diese treten als Zugimpulse in Erscheinung, die insbesondere bei den üblichen fokussierenden Wandlern die Gefahr von Gewebeschädigungen im Fokusumfeld mit sich bringen.Ultrasonic transducers designed in this way are known. Their mode of operation is based on the fact that when a voltage is applied, the piezoceramic transducer element in the interior is suddenly produced a mechanical stress state which arises from the fact that an electrical field builds up in the interior of the transducer element, which causes every layer of the transducer element endeavors to change its thickness. If the electrodes of the ceramic bodies of the transducer elements are parallel, a homogeneous electric field is generated inside them, which generates transducer elements with negative signs in addition to positive pressure pulses when the transducer elements are attached to a reflection-free backing (backing). These appear as pulling impulses, which in particular with the usual focusing transducers entail the risk of tissue damage in the focus environment.

Um diese Gefahr zu minimieren,hat man verschiedene Maßnahmen getroffen, die eine Reduzierung der Amplitude der emittierten negativen Pulswellen zum Ziel haben.In order to minimize this danger, various measures have been taken to reduce the amplitude of the emitted negative pulse waves.

So ist aus der DE-PS 34 25 992 ein piezoelektrischer Wandler zu entnehmen, bei dem eine Vielzahl von Wandlerelementen an der Frontseite eines kugelkalottenförmigen Trägers angeordnet sind. Dabei ist das Kalottenmaterial so gewählt, daß dessen Wellenwiderstand von dem der Keramikelemente kaum abweicht und die Rückseite der Oberfläche der Kalotte so gestaltet, daß die daran reflektierten, von den Keramikelementen erzeugten Schallwellen nicht fokussiert werden.Damit läßt sich zwar ein günstiges Verhältnis der Amplituden der positiven und der negativen Pulse erreichen, jedoch kann eine erwünschte weitere Reduzierung der negativen Pulse nicht erreicht werden, da deren Form an der Grenzschicht Wandlerelement-Träger durch die vorhandene Geometrie der Wandlerelemente und der Elektrodenanordnung vorgegeben ist.For example, DE-PS 34 25 992 shows a piezoelectric transducer in which a plurality of transducer elements are arranged on the front of a spherical cap-shaped carrier. The dome material is selected so that its wave resistance hardly differs from that of the ceramic elements and the back of the surface of the dome is designed in such a way that the sound waves reflected on it, generated by the ceramic elements, are not focused. This allows a favorable ratio of the amplitudes of the achieve positive and negative pulses, but a desired further reduction of the negative pulses cannot be achieved, since their shape at the transducer element carrier interface is predetermined by the existing geometry of the transducer elements and the electrode arrangement.

Die DE-OS 31 19 295 zeigt eine weitere Einrichtung zur Zerstörung von Konkrementen, bei der die Gefahr der Gewebeschädigung dadurch reduziert wird, daß der auf das Konkrement zu fokussierende Ultraschallwandler so großflächig ist,daß einerseits die Schalleistungsdichte auf dem Transmissionsweg klein, andererseits im Fokus aber so groß ist, daß sie zur Zerstörung des im Fokus befindlichen Konkrementes ausreicht.DE-OS 31 19 295 shows a further device for destroying concrements, in which the risk of tissue damage is reduced by the fact that the ultrasound transducer to be focused on the concretion is so large that on the one hand, the sound power density on the transmission path is small, but on the other hand the focus is so large that it is sufficient to destroy the concretion in focus.

Es ist daher die Aufgabe der Erfindung, einen Ultraschallwandler mit hoher Schalleistungsdichte im Fokus zu schaffen, bei dem der negative Druckpuls so weit reduziert ist, daß jegliche Gefahr einer Gewebeschädigung im Umfeld des Konkrementes und auf dem Transmissionsweg vermieden wird.It is therefore the object of the invention to provide an ultrasound transducer with a high sound power density in focus, in which the negative pressure pulse is reduced to such an extent that any risk of tissue damage in the vicinity of the concrement and on the transmission path is avoided.

Diese Aufgabe wird erfindungsgemäß dadurch gelöst, daß die Elektroden so ausgebildet und derart angeordnet sind, daß im Bereich des einen Endes der Wandlerelemente ein homogenes Feld und im gegenüberliegenden Bereich der Wandlerelemente ein inhomogenes Feld erzeugbar ist. Das kann dadurch erreicht werden, daß die zweiten Elektroden eine wenigstens teilweise zu den ersten Elektroden abweichend verlaufende Form haben und konkret dadurch, daß die zweiten, topfförmig ausgebildeten Elektroden jeweils den einen Bereich der Wandlerelemente vollständig einschließen.This object is achieved in that the electrodes are designed and arranged in such a way that a homogeneous field can be generated in the region of one end of the transducer elements and an inhomogeneous field in the opposite region of the transducer elements. This can be achieved in that the second electrodes have an at least partially different shape from the first electrodes and specifically in that the second, cup-shaped electrodes each completely enclose one area of the transducer elements.

Durch diese Maßnahme erhöht sich die Amplitude des positiven Druckpulses, während gleichzeitig die des negativen Druckpulses reduziert und dessen zeitliche Dauer vergrößert wird. Es ergibt sich also ein gegenläufiges Verhalten bei der Entstehung der positiven und negativen Druckpulse, wobei die Dauer multipliziert mit dem Quadrat der Amplitude ein Maß für die in dem jeweiligen Druckpuls enthaltene Energiedichte darstellt.This measure increases the amplitude of the positive pressure pulse, while at the same time reducing that of the negative pressure pulse and increasing its duration. The result is opposite behavior when the positive and negative pressure pulses are generated, the duration multiplied by the square of the amplitude being a measure of the energy density contained in the respective pressure pulse.

Nach einer bevorzugten Ausführung kann der Boden der topfförmigen zweiten Elektroden parallel zu den ersten Elektroden verlaufen. Die zweiten Elektroden können aber auch in Form von Ringen ausgebildet sein, die auf gleicher Achse wie die ihnen zugeordneten Wandlerelemente liegen und jeweils den rückseitigen Teil der Wandlerelemente einfassen.According to a preferred embodiment, the bottom of the cup-shaped second electrodes can run parallel to the first electrodes. However, the second electrodes can also be designed in the form of rings which lie on the same axis as the transducer elements assigned to them and each surround the rear part of the transducer elements.

Dabei kann die elektrische Verbindung rückseitig dadurch erfolgen, daß die rückseitigen Endflächen der Wandlerelemente und der Ringe elektrisch leitend mit dem ebenfalls leitenden Träger verbunden werden. Eine weitere Möglichkeit der rückseitigen elektrischen Verbindung besteht darin, daß die zweiten Elektroden durch Ausnehmungen im elektrisch leitenden Träger gebildet sind, und daß die Elektroden mit ihren rückseitigen Teilen in den Ausnehmungen festgelegt sind. Der frontseitige elektrische Anschluß der Wandlerelemente kann dadurch erfolgen, daß die frontseitigen Enden der Wandlerelemente gemeinsam mit einem die ersten Elektroden bildenden elektrischen Leiter abgedeckt sind.The electrical connection can be made on the rear side in that the rear end surfaces of the transducer elements and the rings are connected in an electrically conductive manner to the likewise conductive carrier. Another possibility of the rear electrical connection is that the second electrodes are formed by recesses in the electrically conductive carrier and that the electrodes with their rear parts are fixed in the recesses. The electrical connection of the transducer elements at the front can take place in that the front ends of the transducer elements are covered together with an electrical conductor forming the first electrodes.

Der erfindungsgemäße Schallwandler ist nachstehend anhand einiger,in den Zeichnungen dargestellter Ausführungsbeispiele näher erläutert. Es zeigen:

Figur 1
einen fokussierenden Ultraschallwandler bekannter Bauart,
Figur 2
einen Querschnitt durch den Ultraschallwandler nach Figur 1 mit einer erfindungsgemäßen Ausbildung der trägerseitigen Elektroden,
Figur 3
eine vergrößerte schematische Schnittdarstellung eines erfindungsgemäßen Wandlerelementes mit dem nach Anlegen einer Spannung in diesem entstehenden elektrischen Feld,
Figur 4
eine Variante der Ausbildung der Elektroden für den elektrischen Anschluß der Wandlerelemente,
Figur 5,6 und 7
verschiedene erfindungsgemäße Ausgestaltungen der rückseitigen Elektroden.
The sound transducer according to the invention is explained in more detail below with the aid of some exemplary embodiments shown in the drawings. Show it:
Figure 1
a focusing ultrasonic transducer of a known type,
Figure 2
2 shows a cross section through the ultrasound transducer according to FIG. 1 with an inventive design of the electrodes on the carrier,
Figure 3
2 shows an enlarged schematic sectional illustration of a transducer element according to the invention with the electrical field which arises after a voltage has been applied to it,
Figure 4
a variant of the design of the electrodes for the electrical connection of the transducer elements,
Figures 5,6 and 7
Various configurations of the rear electrodes according to the invention.

In Figur 1 ist ein fokussierender Ultraschallwandler 1 gezeigt, der eine Vielzahl von piezoelektrischen Ultraschall-Wandlerelementen 2 in einer Ringanordnung um die Mittelachse aufweist. Der Ultraschallwandler 1 ist kugelkalottenförmig gestaltet und ist damit mechanisch fokussiert und kann darüber hinaus in bekannter und daher nicht näher zu beschreibender Weise elektronisch fokussierbar sein.FIG. 1 shows a focusing ultrasound transducer 1 which has a multiplicity of piezoelectric ultrasound transducer elements 2 in a ring arrangement around the central axis. The ultrasound transducer 1 is designed in the shape of a spherical cap and is therefore mechanically focused and, moreover, can be electronically focused in a known and therefore not to be described in detail.

Die Wandlerelemente 2 sind gemäß Figur 2 mit ihren rückseitigen Enden auf einem elektrisch leitfähigen Träger 3, der eine kalottenförmige Grundgestalt hat, vorzugsweise durch Kleben befestigt. Jedes Wandlerelement 2 ist dabei, wie besser in Figur 3 zu erkennen ist, an seinem rückseitigen Ende durch eine topfförmige Elektrode 4 eingefaßt, so daß diese den Kontakt zu dem elektrisch leitfähigen Träger 3 bildet. Dieser Kontakt wird durch Anwendung eines ebenfalls elektrisch leitfähigen Klebers sichergestellt. Die topfförmige Ausbildung der Elektrode 4 bewirkt, daß nicht nur die ebene Stirnfläche der Wandlerelemente 2 elektrisch leitend angeschlossen ist, sondern auch Teile der seitlichen Begrenzungsflächen derselben. Dieser Umstand bewirkt, daß bei Anlegen einer Spannung zwischen einer frontseitigen Elektrode 5 und den rückseitigen topfförmigen Elektroden 4 ein elektrisches Feld wie in Figur 3 durch seine Äquipotentiallinien angedeutet aufgebaut wird, das in den Wandlerelementen 2 frontseitig homogen und rückseitig inhomogen ist, da hier eine Verzerrung durch die Topfform der Elektrode 4 eintritt. Um diesen erwünschten Effekt zu erreichen, ist Voraussetzung, daß das rückseitige, inhomogene elektrische Feld das frontseitige,homogene Feld nicht bzw. nur unwesentlich beeinflußt, was sichergestellt ist, wenn der Durchmesser des Wandlerelementes 2 seine Höhe nicht wesentlich überschreitet. Die frontseitige Elektrode 5 kann in Form einer elektrisch leitfähigen Folie vorgesehen sein, mit der die frontseitigen Stirnflächen der Wandlerelemente 2 verbunden werden.The transducer elements 2 are fastened according to FIG. 2 with their rear ends to an electrically conductive carrier 3, which has a dome-shaped basic shape, preferably by gluing. Each converter element 2, as can be seen better in FIG. 3, is bordered at its rear end by a cup-shaped electrode 4, so that it forms the contact with the electrically conductive carrier 3. This contact is ensured by using an electrically conductive adhesive. The cup-shaped design of the electrode 4 has the effect that not only the flat end face of the transducer elements 2 is electrically conductively connected, but also parts of the lateral boundary surfaces thereof. This fact has the effect that when a voltage is applied between a front electrode 5 and the rear cup-shaped electrodes 4, an electrical field as indicated in FIG. 3 by its equipotential lines is built up, which is homogeneous in the transducer elements 2 on the front and inhomogeneous on the back, since here a distortion occurs enters through the pot shape of the electrode 4. In order to achieve this desired effect, it is a prerequisite that the inhomogeneous electric field on the rear side does not influence the homogeneous field on the front side or only insignificantly, which is ensured if the diameter of the transducer element 2 does not significantly exceed its height. The front electrode 5 can be provided in the form of an electrically conductive film to which the front faces of the transducer elements 2 are connected.

Der Aufbau des Ultraschall-Wandlers 1 nach Fig. 4 sieht vor, daß die Wandlerelemente 2 mit ihren frontseitigen Stirnflächen an einer die Schallenergie leitenden und elektrisch leitfähigen Platte 6 befestigt und die rückseitig an den Wandlerelementen 2 angebrachten topfförmigen Elektroden 4 einzeln miteinander elektrisch leitend verbunden werden.The structure of the ultrasound transducer 1 according to FIG. 4 provides that the transducer elements 2 are attached with their front faces to a plate 6 that conducts sound energy and is electrically conductive, and the cup-shaped electrodes 4 attached to the back of the transducer elements 2 are individually electrically conductively connected to one another .

Nach Fig. 5 sind die erfindungsgemäß ausgestalteten Wandlerelemente 2 mit ihren rückseitigen, durch topfförmige Elektroden 4 eingefaßten Enden auf einer ebenen Trägerfläche befestigt und nach Fig. 6 in eine Ausnehmung 7 in dem Träger 3 eingepaßt, womit die topfförmige Ausgestaltung der Elektrode 4 gegeben ist. Nach Fig. 7 ist eine kegelförmige Ausnehmung 8 vorgesehen, die ebenfalls eine Inhomogenität des elektrischen Feldes im Bereich des rückseitigen Endes des Wandlerelementes 2 bewirkt.According to FIG. 5, the transducer elements 2 designed according to the invention are fastened with their rear ends, bordered by cup-shaped electrodes 4, to a flat support surface and, according to FIG. 6, are fitted into a recess 7 in the support 3, thus giving the cup-shaped configuration of the electrode 4. 7, a conical recess 8 is provided, which likewise causes an inhomogeneity of the electrical field in the region of the rear end of the transducer element 2.

Die pulsweise elektrische Beaufschlagung der Wandlerelemente 2 erfolgt in bekannter Weise durch einen Impulsgenerator 9, dessen Pole einerseits an dem Träger 3 und andererseits an der die Front-Stirnseiten der Wandlerelemente 2 verbindenden Folie angeschlossen werden.The pulse-wise electrical impingement of the transducer elements 2 takes place in a known manner by means of a pulse generator 9, the poles of which are connected on the one hand to the carrier 3 and on the other hand to the film connecting the front ends of the transducer elements 2.

Claims (8)

Ultraschallwandler für die Lithotripsie, bei dem piezoelektrische Wandlerelemente an einem Träger befestigt sind und frontseitig mit ersten sowie rückseitig mit zweiten Elektroden verbunden sind, die an einen elektrischen Impulsgenerator anschließbar sind, um über die Elektroden impulsweise elektrische Felder in den Wandlerelementen zu erzeugen und diese zum Schwingen anzuregen,dadurch gekennzeichnet, daß die Elektroden (4 bzw. 5) so ausgebildet und derart angeordnet sind, daß im Bereich des einen Endes der Wandlerelemente (2) ein homogenes Feld und im gegenüberliegenden Bereich der Wandlerelemente (2) ein inhomogenes Feld erzeugbar ist (Figuren 1 bis 6).Ultrasound transducer for lithotripsy, in which piezoelectric transducer elements are attached to a carrier and are connected on the front to first and at the rear to second electrodes, which can be connected to an electrical pulse generator in order to generate electrical fields in pulses in the transducer elements and to cause them to vibrate to excite, characterized in that the electrodes (4 or 5) are designed and arranged such that a homogeneous field can be generated in the area of one end of the transducer elements (2) and an inhomogeneous field in the opposite area of the transducer elements (2) ( Figures 1 to 6). Ultraschallwandler nach Anspruch 1, dadurch gekennzeichnet, daß die zweiten Elektroden (4) eine wenigstens teilweise zu den ersten Elektroden abweichend verlaufende Form haben. (Figuren 1 bis 6).Ultrasonic transducer according to claim 1, characterized in that the second electrodes (4) have an at least partially different shape from the first electrodes. (Figures 1 to 6). Ultraschallwandler nach den Ansprüchen 1 und 2, dadurch gekennzeichnet, daß die zweiten Elektroden (4) topfförmig ausgebildet jeweils den rückseitigen Teil der Wandlerelemente (2) einschließen.(Figuren 1 bis 4).Ultrasonic transducer according to claims 1 and 2, characterized in that the second electrodes (4) are cup-shaped and each enclose the rear part of the transducer elements (2) (Figures 1 to 4). Ultraschallwandler nach Anspruch 3, dadurch gekennzeichnet, daß der Boden der topfförmigen zweiten Elektroden(4) parallel zu den ersten Elektroden (5) verläuft. (Figuren 1 bis 4)Ultrasonic transducer according to claim 3, characterized in that the bottom of the cup-shaped second electrodes (4) runs parallel to the first electrodes (5). (Figures 1 to 4) Ultraschallwandler nach den Ansprüchen 1 und 2, dadurch gekennzeichnet, daß die zweiten Elektroden (4) als Ringe ausgebildet sind, die auf gleicher Achse wie die ihnen zugeordneten Wandlerelemente (2) liegen und jeweils den rückseitigen Teil der Wandlerelemente (2) einfassen.(Figur 5)Ultrasonic transducer according to claims 1 and 2, characterized in that the second electrodes (4) are designed as rings which lie on the same axis as the transducer elements (2) assigned to them and each surround the rear part of the transducer elements (2) 5) Ultraschallwandler nach Anspruch 5, dadurch gekennzeichnet, daß die rückseitigen Endflächen der Wandlerelemente (2) und der Ringe elektrisch leitend mit dem ebenfalls leitenden Träger (3) verbunden sind. (Figur 5)Ultrasonic transducer according to claim 5, characterized in that the rear end faces of the transducer elements (2) and the rings are electrically conductively connected to the likewise conductive carrier (3). (Figure 5) Ultraschallwandler nach den Ansprüchen 1 und 2, dadurch gekennzeichnet, daß die zweiten Elektroden (4) durch Ausnehmungen (7 bzw. 8) im elektrisch leitenden Träger (3) gebildet sind und daß die Elektroden mit ihren rückseitigen Teilen in den Ausnehmungen (7 bzw. 8) festgelegt sind. (Figuren 6 und 7)Ultrasonic transducer according to claims 1 and 2, characterized in that the second electrodes (4) are formed by recesses (7 or 8) in the electrically conductive carrier (3) and that the electrodes with their rear parts in the recesses (7 or 8) are set. (Figures 6 and 7) Ultraschallwandler nach einem der Ansprüche 1 bis 7,dadurch gekennzeichnet, daß die frontseitigen Enden der Wandlerelemente (2) gemeinsam mit einem die ersten Elektroden (5) bildenden elektrischen Leiter abgedeckt sind. (Figuren 2 und 4)Ultrasonic transducer according to one of claims 1 to 7, characterized in that the front ends of the transducer elements (2) are covered together with an electrical conductor forming the first electrodes (5). (Figures 2 and 4)
EP19900122050 1990-01-09 1990-11-17 Ultrasonic transducer using piezoelectric elements Withdrawn EP0436809A3 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE4000362 1990-01-09
DE4000362A DE4000362C2 (en) 1990-01-09 1990-01-09 Ultrasonic transducer with piezoelectric transducer elements

Publications (2)

Publication Number Publication Date
EP0436809A2 true EP0436809A2 (en) 1991-07-17
EP0436809A3 EP0436809A3 (en) 1992-07-22

Family

ID=6397744

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19900122050 Withdrawn EP0436809A3 (en) 1990-01-09 1990-11-17 Ultrasonic transducer using piezoelectric elements

Country Status (3)

Country Link
US (1) US5101133A (en)
EP (1) EP0436809A3 (en)
DE (1) DE4000362C2 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1997016260A1 (en) * 1995-11-02 1997-05-09 Sonident Anstalt Piezoelectric ultrasonic transducer
EP1452141A1 (en) 2003-02-26 2004-09-01 HMT High Medical Technologies AG Shock wave generating device

Families Citing this family (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5329202A (en) * 1991-11-22 1994-07-12 Advanced Imaging Systems Large area ultrasonic transducer
DE4307669C2 (en) * 1993-03-11 1995-06-29 Wolf Gmbh Richard Device for generating sound pulses for medical applications
US5438998A (en) * 1993-09-07 1995-08-08 Acuson Corporation Broadband phased array transducer design with frequency controlled two dimension capability and methods for manufacture thereof
US5415175A (en) * 1993-09-07 1995-05-16 Acuson Corporation Broadband phased array transducer design with frequency controlled two dimension capability and methods for manufacture thereof
US5743855A (en) * 1995-03-03 1998-04-28 Acuson Corporation Broadband phased array transducer design with frequency controlled two dimension capability and methods for manufacture thereof
US5595178A (en) * 1994-10-02 1997-01-21 Hmt High Medical Technologies Gmbh System, method and apparatus for treatment of degenerative bone
DE19733233C1 (en) * 1997-08-01 1998-09-17 Wolf Gmbh Richard Electroacoustic transducer
WO2005120355A1 (en) * 2004-06-07 2005-12-22 Olympus Corporation Electrostatic capacity type ultrasonic transducer
EP1832314B8 (en) * 2004-12-27 2023-07-19 Chengdu Heuk Medical Equipment Co., Ltd Quasi-self focusing high intensity and large power ultrasonic transducer
JP4703382B2 (en) * 2005-02-14 2011-06-15 富士フイルム株式会社 Structure of transducer array, manufacturing method thereof, and ultrasonic probe
WO2016054448A1 (en) 2014-10-02 2016-04-07 Chirp Microsystems Piezoelectric micromachined ultrasonic transducers having differential transmit and receive circuitry
CN105234063A (en) * 2015-11-06 2016-01-13 中国科学院深圳先进技术研究院 Single-element ultrasonic low-frequency transducer based on radial mode
DE102021128282B4 (en) 2021-10-29 2023-08-24 Pi Ceramic Gmbh mounting device

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0326701A2 (en) * 1988-02-04 1989-08-09 Dornier Medizintechnik Gmbh Piezoelectric shockwaves source
EP0421286A2 (en) * 1989-10-03 1991-04-10 Richard Wolf GmbH Piezoelectric transducer

Family Cites Families (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4183007A (en) * 1978-02-22 1980-01-08 Fischer & Porter Company Ultrasonic transceiver
US4217684A (en) * 1979-04-16 1980-08-19 General Electric Company Fabrication of front surface matched ultrasonic transducer array
DE3119295A1 (en) * 1981-05-14 1982-12-16 Siemens AG, 1000 Berlin und 8000 München DEVICE FOR DESTROYING CONCRETE IN BODIES
US4460841A (en) * 1982-02-16 1984-07-17 General Electric Company Ultrasonic transducer shading
US4551647A (en) * 1983-03-08 1985-11-05 General Electric Company Temperature compensated piezoelectric transducer and lens assembly and method of making the assembly
US4608507A (en) * 1984-06-29 1986-08-26 Micro Pure Systems, Inc. Damping device for focused piezoelectric transducer
DE3425992C2 (en) * 1984-07-14 1986-10-09 Richard Wolf Gmbh, 7134 Knittlingen Piezoelectric converter for the destruction of calculus inside the body
JPH0660896B2 (en) * 1984-11-02 1994-08-10 株式会社日立製作所 Ultrasonic probe
US4604543A (en) * 1984-11-29 1986-08-05 Hitachi, Ltd. Multi-element ultrasonic transducer
DE3545353A1 (en) * 1985-12-20 1987-06-25 Siemens Ag Method and device for measuring the acoustic power of a focused ultrasonic field
JPS6382100A (en) * 1986-09-26 1988-04-12 Hitachi Ltd Piezoelectric element and its manufacture
DE3761731D1 (en) * 1986-11-04 1990-03-29 Siemens Ag ULTRASONIC SENSOR.

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0326701A2 (en) * 1988-02-04 1989-08-09 Dornier Medizintechnik Gmbh Piezoelectric shockwaves source
EP0421286A2 (en) * 1989-10-03 1991-04-10 Richard Wolf GmbH Piezoelectric transducer

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1997016260A1 (en) * 1995-11-02 1997-05-09 Sonident Anstalt Piezoelectric ultrasonic transducer
EP1452141A1 (en) 2003-02-26 2004-09-01 HMT High Medical Technologies AG Shock wave generating device

Also Published As

Publication number Publication date
DE4000362A1 (en) 1991-07-11
EP0436809A3 (en) 1992-07-22
DE4000362C2 (en) 1993-11-11
US5101133A (en) 1992-03-31

Similar Documents

Publication Publication Date Title
DE3888273T2 (en) Medical apparatus for treatment with ultrasound.
DE4000362C2 (en) Ultrasonic transducer with piezoelectric transducer elements
EP0300315B1 (en) Shock wave generator for an apparatus for non-contact disintegration of concrements, present in a body
DE2345088C2 (en) Ultrasonic receiver for real-time detection of part of a sound pressure field of an area to be observed
DE69112527T2 (en) HIGH-STRENGTH ULTRASONIC FOCUSING DEVICE WITH FACETED BRACKET.
EP0298334B1 (en) Shock wave generator
EP0326701B1 (en) Piezoelectric shockwaves source
EP0421286B1 (en) Piezoelectric transducer
EP0308644B1 (en) Focusing ultrasonic transducer
DE3214789C2 (en)
DE60203922T2 (en) DEVICE AND METHOD FOR GENERATING HIGH-PRESSURE RATE SOUND IMPULSES
DE2718772B2 (en) Ultrasonic probe for an ultrasonic diagnostic device with sector-shaped scanning
DE2712341A1 (en) ULTRASONIC CONVERTER WITH VARIABLE FOCUS
DE6609583U (en) PIEZOELECTRIC CONVERTER.
DE3313887C2 (en) Sound transducer for a tone alarm device
EP0267475A1 (en) Ultrasonic sensor
DE4130798A1 (en) SHOCK WAVE SOURCE FOR ACOUSTIC SHOCK WAVES
DE3634378C2 (en)
DE4307669C2 (en) Device for generating sound pulses for medical applications
DE10018355A1 (en) Ultrasound transducer; has piezoelectric body with several transducer elements and strip conductor foil on flat side with conductive track pattern to determine arrangement of transducer elements
DE4125088C1 (en)
EP2311391B1 (en) Electro-acoustic converter
DE3940808C2 (en)
DE19833213C2 (en) Ultrasonic transmission arrangement
DE102021128282B4 (en) mounting device

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A2

Designated state(s): BE DE FR GB IT

PUAL Search report despatched

Free format text: ORIGINAL CODE: 0009013

AK Designated contracting states

Kind code of ref document: A3

Designated state(s): BE DE FR GB IT

17P Request for examination filed

Effective date: 19920715

17Q First examination report despatched

Effective date: 19930625

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 19940920