EP0196139B1 - Montage de sonde avec transducteur ultrasonore à double ouverture - Google Patents

Montage de sonde avec transducteur ultrasonore à double ouverture Download PDF

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Publication number
EP0196139B1
EP0196139B1 EP86200472A EP86200472A EP0196139B1 EP 0196139 B1 EP0196139 B1 EP 0196139B1 EP 86200472 A EP86200472 A EP 86200472A EP 86200472 A EP86200472 A EP 86200472A EP 0196139 B1 EP0196139 B1 EP 0196139B1
Authority
EP
European Patent Office
Prior art keywords
transducer
interior space
regions
reed switch
assembly
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.)
Expired - Lifetime
Application number
EP86200472A
Other languages
German (de)
English (en)
Other versions
EP0196139A3 (en
EP0196139A2 (fr
Inventor
Perry Kaminski
Eugene A. Larson
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.)
Technicare Corp
Original Assignee
Technicare Corp
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
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First worldwide family litigation filed litigation Critical https://patents.darts-ip.com/?family=27017086&utm_source=google_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=EP0196139(B1) "Global patent litigation dataset” by Darts-ip is licensed under a Creative Commons Attribution 4.0 International License.
Priority claimed from US06/400,551 external-priority patent/US4445380A/en
Application filed by Technicare Corp filed Critical Technicare Corp
Publication of EP0196139A2 publication Critical patent/EP0196139A2/fr
Publication of EP0196139A3 publication Critical patent/EP0196139A3/en
Application granted granted Critical
Publication of EP0196139B1 publication Critical patent/EP0196139B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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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
    • G10K11/18—Methods or devices for transmitting, conducting or directing sound
    • G10K11/26—Sound-focusing or directing, e.g. scanning
    • G10K11/32—Sound-focusing or directing, e.g. scanning characterised by the shape of the source
    • 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
    • G10K11/18—Methods or devices for transmitting, conducting or directing sound
    • G10K11/26—Sound-focusing or directing, e.g. scanning
    • 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
    • G10K11/18—Methods or devices for transmitting, conducting or directing sound
    • G10K11/26—Sound-focusing or directing, e.g. scanning
    • G10K11/30—Sound-focusing or directing, e.g. scanning using refraction, e.g. acoustic lenses

Definitions

  • This application is a divisional application derived from EP-A-0 102 179.
  • the invention which is the subject of the above application relates to ultrasonic transducers for diagnostic imaging of a novel geometric design with reduced sidelobe patterns, and provides an ultrasonic transducer assembly including a piezoelectric material, the transducer exhibiting an effective radiating surface having a center point characterised in that said effective radiating surface has an aspheric, semi-conical configuration resembling a concave spherical surface with opposite sides relative to the center of the surface canted toward each other.
  • the present invention relates to a dual aperture ultrasonic transducer probe assembly for diagnostic imaging.
  • Ultrasonic transducers are used in ultrasonic diagnostic systems to transmit waves of ultrasonic energy into a patient's body. Tissue interfaces in the body reflect some of this energy back toward the transducer in the form of echoes. The echoes are received by the transducer and converted into electrical signals. The signals may be processed by associating them with their times of arrival to reconstruct an image of the tissue or make fluid flow measurements.
  • GB-A-2 079 456 discloses a dual aperture transducer probe for an ultrasonic diagnostic system, in which the transducer has first and second electrically separate regions, time-controlled switches connected to respective regions to allow their selective coupling, the coupling of the separate regions being determined by the operator.
  • the operator sets, in advance, the gain inputs of variable gain amplifiers corresponding to the respective regions, so as to determine their relative amplification, the amplifier outputs being summed to provide a signal for further processing.
  • the present invention provides a dual aperture ultrasonic probe assembly for an ultrasonic diagnostic system comprising: a housing having an electrically shielded interior space; a dual aperture transducer having first and second electrically separate regions, said transducer being located at one end of said housing; means located in a wall of said housing, for making an electrical connection between said interior space and the exterior of said housing; a reed switch, located in said shielded interior space and connected to said first and second transducer regions and said electrical connection means for selectively coupling said regions to said connection means; and a magnet located external to said shielded interior space and movably mounted so as to selectively open and close said reed switch for varying the coupling of said transducer regions to said electrical connection means.
  • a probe assembly of this type, but used in connection with a transducer exhibiting an aspheric, semiconical effective radiating surface, is claimed in parent application EP-A-102 179.
  • the reed switch has a first terminal coupled to said first transducer region and a second terminal coupled to said second transducer region and said electrical connection means comprises an r.f. connector having a conductor connected to said first reed switch terminal.
  • the assembly preferably further comprises a tuned circuit located in said shielded interior space and a second reed switch located in said shielded interior space in close proximity to said external magnet and connected to said transducer and said tuned circuit for selectively coupling said tuned circuit to said transducer.
  • the assembly may include an annulus of backing material affixed to the back of the transducer around the perimeter thereof, whereby sidelobes of the transducer are reduced by apodisation.
  • the transducer material is divided into a center disc and an annular ring.
  • the center disc is activated, the range of optimal focus is located a relatively short distance from the transducer.
  • the range of optimal focus is located at a relatively greater distance from the transducer.
  • the transducer electronics including the switch contacts are surrounded by a continuous shield in order to prevent the introduction of noise into the received echo signals.
  • the use of a reed switch thus permits the focal ranges to be switched without physically interrupting the shield and hence impairing the noise characteristic of the transducer assembly
  • a conical transducer is shown in cross-section.
  • the transducer includes a conical surface 12 of piezoelectric ceramic material on a backer 10.
  • the conical transducer exhibits an idealized aperture outlined at 16, which comprises a line of geometric focal points 14 emanating from the center of the transducer.
  • Conical transducers are advantageous in that they exhibit a narrow region of sharply defined focal points. Their disadvantage is that the energy emitted by the conical surface is relatively evenly distributed over the line of focal poionts. It would be desirable to be able to concentrate the emitted energy in a particular region of the aperture, so as to improve the sensitivity of the transducer at a particular tissue depth of interest.
  • FIGURE 2a illustrates a spherical transducer in cross-section.
  • This transducer includes a spherical surface 22 of piezoelectric material mounted on a backer 20.
  • the spherical transducer exhibits an idealized aperture outlined at 26, which contains a single geometric focal point 24.
  • the ultrasonic energy emitted from the spherical surface of the transducer 22 converges at this point, and diverges beyond it.
  • the spherical transducer is capable of producing sharply focussed images of tissue in the vicinity of the geometric focal point 24 by reason of the concentrated ultrasonic energy at the point.
  • the aperture is only sharply focused at one point, the resolution degrading at regions removed from this point.
  • a conical transducer such as that shown in FIGURE 1a will exhibit a lobe pattern as shown in FIGURE 1b, with a large main lobe 40 and sizeable sidelobes 42, 42'.
  • the large sidelobes 42 and 42' are undesirable in an ultrasonic diagnostic system.
  • the spherial transducer of FIGURE 2a will exhibit a more acceptable lobe pattern as shown in FIGURE 2b.
  • the pattern there shown includes a large main lobe 50 and small sidelobes 52, 52'.
  • the lobe pattern of a transducer can be improved by providing backing material around the outer perimeter of the transducer.
  • This ring of backing material damps vibrations at the outer perimeter of the piezoelectric material thereby reducing the energy radiated from the perimeter of the piezoelectric material.
  • the ring of backing material may be extended to back the central region to damp vibrations at the perimeter of the central region when it is operated alone.
  • This damping technique generally referred to as apodizing, causes the transducer to be a non-uniform radiator, which "smears" the small side lobes of the transducer.
  • FIGURE 3a illustrates the focal pattern of a simple dual aperture spherical transducer, including a central spherical region 120 and an outer annular region 122.
  • the transducer When both regions 120 and 122 of the transducer are activated simultaneously the transducer exhibits an aperture outlined at 124, which narrows sharply at a focal region 125. Focusing is ineffective beyond the near field limit 129 of the transducer, which is approximately equal to the radius of the transducer squared, divided by the wavelength of operation.
  • the near field limit 129 is thus a linear function of the area of the transducer, which in this case is the total of both regions 120 and 122.
  • the aperture is as outlined by dotted lines 126.
  • This aperture produces a focal region 127 closer to the transducer, with a near field limit at 128 by reason of the reduced area of the transducer.
  • the aperture outlined at 126 does not narrow as sharply as the aperture outlined at 124, however, and the focal region 127 has a greater lateral dimension 1 than focal region 125. This is because the focus is changed by changing the near field limit from 129 to 128; the geometric focus remains the same, generally located slightly beyond the far focal region 125.
  • FIGURE 3b illustrates the focal pattern of a simple dual aperture conical transducer having an inner conical surface 130 and an outer annular surface 132.
  • the energy from surface 130 focuses along the broken line shown at 137 and bounded by dotted lines 136.
  • both regions 130 and 132 are activated, the line of focal points is extended to include the points indicated at 135 as well as those at 137, bounded by dashed lines 134. Switching from operation using both regions to operation using only the center region 130 reduces the near field limit, since the transducer area changes, and also reduces the geometric focal length to only the focal points included in aperture outline 136. A line of distributed energy points is produced in both cases.
  • a dual aperture ultrasonic transducer is conveniently mounted in a probe assembly according to the present invention such as that shown in FIGURE 4.
  • the probe assembly there shown advantageously provides an electrically shielded environment which reduces the tendency to pick up stray electronic interference.
  • the probe assembly also provides a means for switching the focus of the transducer in a manner which does not interrupt the shielded environment. As the focus of the transducer is switched, the tuning of the transducer is also changed and a signal is provided which indicates the selected focal characteristics.
  • the probe assembly of FIGURE 4 includes a forward plastic cylindrical section 150 with a closed acoustic window face 151.
  • the transducer 152 is located behind the window 151.
  • Leads 156 extend from the separate regions of the transducer.
  • the interior of the cylindrical section 150 is lined with a nonmagnetic shield 154 such as copper.
  • the rear portion of the cylindrical section 150 narrows to a smaller diameter as indicated by dividing ridge 157.
  • Two dimples shown at 158 are provided on the outside of the narrow portion which form a portion of the detent mechanism of the switch.
  • the end 159 of the cylindrical section 150 is open.
  • a plastic ring 160 slides over the narrow portion of the cylindrical section 150 up to the ridge 157.
  • a small ball 162 which rides between the dimples 158 and snaps into them to provide a detent mechanism for the ring.
  • a groove 168 is formed around the inner surface of the ring to hold a magnet 164 in a predetermined position relative to the ball bearing 162.
  • a small pin 166 extends from the inner surface of the ring at the bottom of the ring.
  • a rear cylindrical section 170 slides over the remainder of the narrow portion of section 150.
  • a recessed collar 176 is then located under the ring 160.
  • the collar 176 has a slot 174 in it so that pin 166 can move from one end of the slot to the other as the ring 160 is turned. The pin and slot thereby provide a stop for the ring to permit the ring to be turned only through the arc of the slot.
  • the wires 156 from the transducer are soldered to a small printed circuit board 190, mounted on an r.f. connector 180.
  • the r.f. connector 180 is inserted into the open end 159 of the section 150 up to the lip 181 of the connector.
  • Mounted on the connector at a plastic ring 182 are three reed switches 184, 186 and 188.
  • the reed switches are wired to the printed circuit board 190.
  • the r.f. connector 180 and copper shield 154 provide a completely shielded cavity for the wiring, printed circuit board, switches, and board components in the inside of the section 150.
  • the ring performs three switching functions in the probe assembly.
  • the focal characteristics of the transducer are switched between short focus using only the central disc of the transducer, and long focus by connecting the central disc and annular ring of the transducer together to be activated simultaneously.
  • the tuning of the circuitry on circuit board 190 is switched to match the respective electrical characteristics of the transducer in the two operating modes.
  • a resistance value on the circuit board is changed to produce a signal indicative of the operating mode, which signal is coupled out through the connector along with signals to and from the transducer.

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

Claims (4)

  1. Montage de sonde avec transducteur ultrasonore à double ouverture pour un système de diagnostic ultrasonore comprenant:
       une enveloppe (150,160,170) ayant un espace intérieur blindé;
       un transducteur à double ouverture (152) ayant une première et une seconde région séparée électriquement, ledit transducteur (152) étant situé à l'une des extrémités de ladite enveloppe (150);
       des moyens (180) situés dans une paroi de ladite enveloppe, pour établir une liaison électrique entre ledit espace intérieur et l'extérieur de ladite enveloppe;
       un commutateur à contacts sellés (184), situé dans ledit espace intérieur blindé et relié à ladite première et à ladite seconde région avec transducteur et ledit moyen de connexion électrique (180) pour coupler sélectivement lesdites régions audit moyen de liaison (180); et
       un aimant (164) situé à l'extérieur dudit espace intérieur blindé et monté de façon mobile de manière à ouvrir et fermer sélectivement ledit commutateur à contacts sellés (184), pour faire varier le couplage desdites régions avec transducteur, avec ledit moyen de liaison électrique (180).
  2. Montage selon la revendication 1, dans lequel ledit coutateur (184) a une première borne couplée à ladite première région avec transducteur et une seconde borne couplée à ladite seconde région avec transducteur et dans lequel ledit moyen de connexion électrique comprend un connecteur r.f. (180) ayant un conducteur relié à ladite première borne du commutateur à contacts sellés.
  3. Montage selon la revendication 2, comprenant de plus:
       un circuit accordé (190) situé dans ledit espace intérieur blindé; et
       un second commutateur à contacts sellés (186) situé dans ledit espace intérieur blindé à proximité immédiate dudit aimant externe (164) et relié audit transducteur et audit circuit accordé (190) pour coupler sélectivement ledit circuit accordé (190) audit transducteur.
  4. Montage selon l'une quelconque des revendications 1 à 3, comprenant de plus un anneau d'une matière de renforcement fixé au dos du transducteur (152) autour du périmètre de celui-ci.
EP86200472A 1982-07-21 1983-07-20 Montage de sonde avec transducteur ultrasonore à double ouverture Expired - Lifetime EP0196139B1 (fr)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
US40054782A 1982-07-21 1982-07-21
US400551 1982-07-21
US400547 1982-07-21
US06/400,551 US4445380A (en) 1982-07-21 1982-07-21 Selectable focus sphericone transducer and imaging apparatus

Related Parent Applications (1)

Application Number Title Priority Date Filing Date
EP83304222.9 Division 1983-07-20

Publications (3)

Publication Number Publication Date
EP0196139A2 EP0196139A2 (fr) 1986-10-01
EP0196139A3 EP0196139A3 (en) 1990-12-05
EP0196139B1 true EP0196139B1 (fr) 1993-01-20

Family

ID=27017086

Family Applications (2)

Application Number Title Priority Date Filing Date
EP83304222A Expired EP0102179B1 (fr) 1982-07-21 1983-07-20 Transducteurs ultrasonores à distance focale variable pour tomographie
EP86200472A Expired - Lifetime EP0196139B1 (fr) 1982-07-21 1983-07-20 Montage de sonde avec transducteur ultrasonore à double ouverture

Family Applications Before (1)

Application Number Title Priority Date Filing Date
EP83304222A Expired EP0102179B1 (fr) 1982-07-21 1983-07-20 Transducteurs ultrasonores à distance focale variable pour tomographie

Country Status (4)

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EP (2) EP0102179B1 (fr)
AU (1) AU572464B2 (fr)
DE (2) DE3382654T2 (fr)
IL (1) IL69293A0 (fr)

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AU572464B2 (en) * 1982-07-21 1988-05-12 Technicare Corp. Selectable focus ultrasonic transducer
FR2559266B1 (fr) * 1984-02-02 1986-07-04 Comp Generale Electricite Dispositif a ondes acoustiques focalisees pour etudier la structure d'un objet
JPH02159266A (ja) * 1988-12-14 1990-06-19 Matsushita Electric Ind Co Ltd 超音波探触子
JPH02215452A (ja) * 1989-02-17 1990-08-28 Toshiba Corp 結石破砕装置
JPH03176040A (ja) * 1989-09-29 1991-07-31 Terumo Corp 超音波診断装置
EP1005693B1 (fr) * 1997-08-23 2003-02-12 Valeo Schalter und Sensoren GmbH Transducteur ultrasonore comportant une platine montee dans le sens longitudinal dudit transducteur, pour un circuit electrique
DE10114819A1 (de) * 2001-03-26 2002-10-10 Siemens Ag Verfahren zur Verbesserung des Signalempfangs eines Ultraschall-Näherungsschalters und Ultraschall-Näherungsschalter mit verbessertem Signalempfang
US20220373372A1 (en) * 2021-05-19 2022-11-24 Honeywell International Inc. Fluid sensor for bubble and occlusion detection

Family Cites Families (11)

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Publication number Priority date Publication date Assignee Title
US3193198A (en) * 1963-11-12 1965-07-06 Honeywell Inc Control apparatus
JPS4963401A (fr) * 1972-10-18 1974-06-19
US4016751A (en) * 1973-09-13 1977-04-12 The Commonwealth Of Australia Care Of The Department Of Health Ultrasonic beam forming technique
US3958559A (en) * 1974-10-16 1976-05-25 New York Institute Of Technology Ultrasonic transducer
US4138895A (en) * 1977-10-20 1979-02-13 Rca Corporation Switchable depth of focus pulse-echo ultrasonic-imaging display system
US4276779A (en) * 1979-03-29 1981-07-07 Raytheon Company Dynamically focussed array
JPS56158648A (en) * 1980-05-09 1981-12-07 Tokyo Shibaura Electric Co Ultrasonic diagnostic apparatus
US4398539A (en) * 1980-06-30 1983-08-16 Second Foundation Extended focus transducer system
US4445380A (en) * 1982-07-21 1984-05-01 Technicare Corporation Selectable focus sphericone transducer and imaging apparatus
AU572464B2 (en) * 1982-07-21 1988-05-12 Technicare Corp. Selectable focus ultrasonic transducer
US4557146A (en) * 1982-07-21 1985-12-10 Technicare Corporation Selectable focus ultrasonic transducers for diagnostic imaging

Also Published As

Publication number Publication date
AU572464B2 (en) 1988-05-12
IL69293A0 (en) 1983-11-30
EP0196139A3 (en) 1990-12-05
EP0196139A2 (fr) 1986-10-01
EP0102179A1 (fr) 1984-03-07
DE3382654T2 (de) 1993-05-13
EP0102179B1 (fr) 1987-09-16
DE3382654D1 (de) 1993-03-04
DE3373739D1 (en) 1987-10-22
AU1712483A (en) 1984-01-26

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