JPH11347032A - Ultrasonic probe - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To improve operability by narrowing the width of a piezoelectric plate of an ultrasonic probe in a short axis direction, and to improve azimuth resolution at a short distance and penetration at a long distance. SOLUTION: An outlet of a ground electrode 2 formed on a side of an ultrasonic wave emitting surface of a piezoelectric plate 1 of an ultrasonic probe is provided on an exposed portion 7 on an end side surface in a scanning direction, and is connected to the outside by a common ground line 11. I do. Since the short-axis effective opening width is the same as the short-axis direction width of the piezoelectric plate 1, the width of the ultrasonic probe in the short-axis direction can be reduced, and the operability is improved. With the same piezoelectric vibrator width, the short-axis effective aperture width of the ultrasonic wave radiated from the piezoelectric plate 1 becomes large, so that even in the case of scanning from a narrow gap as in the case of intercostal scanning, there is little reflected noise signal from the ribs. A good ultrasonic tomographic image can be obtained. In addition, by dividing the ground electrode of the piezoelectric vibrator in the short-axis direction and selectively switching it with a switch, the short-axis effective aperture width is changed to form an optimal beam according to the measurement area, and the azimuth resolution at short distance And penetration can be improved even in a long distance portion.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic probe, and more particularly to an ultrasonic diagnostic apparatus which emits ultrasonic waves into a subject and displays a tomographic image of the body based on reflected ultrasonic waves. The present invention relates to an ultrasonic probe to be used.

[0002]

2. Description of the Related Art A conventional ultrasonic probe is disclosed in
There is one disclosed in Japanese Patent No. 84194. FIG. 10 shows a schematic perspective view of a conventional ultrasonic probe. The ultrasonic probe is
It comprises a piezoelectric plate 50, a first matching plate 51, a second matching plate 52, an acoustic lens 53, and a backing 54. The piezoelectric plate 50 has electrodes formed on two opposing surfaces. In the ground electrode 55 on the acoustic lens side, a turn-in electrode is formed up to a part of the backing surface of the piezoelectric plate 50 via the side surface of the end of the piezoelectric plate 50 in the short axis direction. The ground electrode 55 wound around the backing side of the piezoelectric plate 50 is electrically connected to the copper foil 56. The signal electrode 57 is electrically connected to a printed board 58 on which a wiring pattern is formed. Each of the electrodes is drawn from the end face of the piezoelectric plate 50 in the short axis direction. Further, the piezoelectric plate 50 and the plurality of matching plates are cut in parallel with the short axis direction. As a result, a channel dividing groove 59 is formed, and a plurality of piezoelectric vibrators 60 are arranged in the scanning direction.

[0003]

In the above conventional ultrasonic probe, the ground electrode 55 of the piezoelectric plate 50 on the acoustic lens side is used.
Is turned up to the backing side of the piezoelectric plate 50. Therefore, the short-axis effective opening width at which the piezoelectric vibrator 60 vibrates is a width obtained by subtracting the width of the feed-back electrode on the backing side and the width of the groove 61 for preventing a short circuit between the signal electrode 57 and the ground electrode 55 from the piezoelectric plate width. . Therefore, the width of the short axis of the ultrasonic probe is equal to or larger than the effective opening width of the short axis, and there is a problem that operability when contacting the subject is deteriorated.

If the short-axis effective aperture width is large, the beam width becomes large and the azimuth resolution is reduced. Therefore, it is preferable that the short-axis effective aperture width be small in a short distance region. Since the distance sound field area becomes short, there is a problem that the beam spreads in a long distance area, and the azimuth resolution and contrast are reduced.

The present invention solves the above-mentioned conventional problems,
It is an object of the present invention to provide an ultrasonic probe having a short minor axis width and excellent operability. It is still another object of the present invention to provide an ultrasonic probe capable of forming an optimum beam according to a measurement region, having excellent azimuth resolution at a short distance, and having excellent penetration even at a long distance.

[0006]

In order to solve the above problems, according to the present invention, an ultrasonic probe is connected to an extraction terminal of an electrode formed on the ultrasonic radiation surface side of a piezoelectric plate in one of scanning directions. The configuration was provided on the side surfaces of both ends.

[0007] With this configuration, the width of the piezoelectric plate and the width of the short-axis effective opening become the same, the width of the short-axis of the piezoelectric plate can be shortened, and the operability is improved.

Further, the ultrasonic probe is divided by arranging a plurality of cuts along the short axis direction of the common ground electrode provided on the surface of the piezoelectric vibrator in the scanning direction, and dividing each common ground electrode in the scanning direction. The common ground electrode is taken out from one or both ends and selectively switched by a switch.

With this configuration, an optimum beam is formed in accordance with the measurement area by changing the effective aperture width of the short axis, thereby improving the azimuth resolution in a short distance and improving the penetration in a long distance portion. be able to.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION
A plurality of piezoelectric vibrators arranged in the ultrasonic scanning direction,
An ultrasonic probe comprising: a conductive layer that commonly connects a ground electrode of the piezoelectric vibrator; and a connection unit that connects the ground electrode to the outside at one or both ends in a scanning direction via the conductive layer. And has the function of making the width of the piezoelectric plate and the effective length of the short axis the same.

The invention according to claim 2 of the present invention is the invention according to claim 1.
The ultrasonic probe according to claim 1, wherein the conductive layer is a conductive acoustic matching layer provided on the ground electrode surface, and the ground electrode is connected to the conductive acoustic matching layer to form a piezoelectric plate. This has the effect of making the width and the minor axis effective opening length the same.

The third aspect of the present invention is the first aspect of the present invention.
3. The ultrasonic probe according to claim 1, wherein the conductive layer is a conductive first acoustic matching layer provided on a ground electrode surface of the piezoelectric vibrator, and a metal thin film layer laminated on the first acoustic matching layer. Wherein the connection means is means for connecting one or both ends of the metal thin film layer or the first acoustic matching layer in one or both sides in the scanning direction to the outside, and the second acoustic layer laminated on the metal thin film layer A matching layer is provided, and the ground electrode is commonly connected between the first acoustic matching layer and the metal thin film layer, and has an effect of making the width of the piezoelectric plate and the effective length of the short axis the same.

According to a fourth aspect of the present invention, in the ultrasonic probe according to the first, second or third aspect, the ultrasonic transducer is arranged adjacent to the piezoelectric vibrator at one or both ends in the scanning direction. And the conductive layer is one or more conductive acoustic matching layers provided on the subject side of the electrode body and the piezoelectric vibrator, and the connecting means externally connects the electrode body. This is a means for connecting the ground electrode of each piezoelectric vibrator and the electrode body at the end with a conductive acoustic matching layer to take out the ground electrode, thereby obtaining the piezoelectric plate width and the short-axis effective aperture. It has the effect of making the length the same.

According to a fifth aspect of the present invention, in the ultrasonic probe according to the first, second or third aspect, the piezoelectric vibrator has a signal electrode and a ground electrode formed on two opposing surfaces, respectively. A piezoelectric vibrator in which a grounding electrode is formed on a part of the signal electrode surface through the end side surface in the scanning direction, and the connection means is provided on one or both ends of the signal electrode surface in the scanning direction. It is a means to connect the turned ground electrode to the outside, and by taking out a common ground electrode from the ground electrode turned on the backing surface, it is said that the width of the piezoelectric plate and the short-axis effective aperture length are made equal. Has an action.

According to a sixth aspect of the present invention, there is provided a piezoelectric vibrator arranged in a scanning direction of an ultrasonic wave, and a conductive first acoustic matching layer provided on the surface of the piezoelectric vibrator. A second acoustic matching layer laminated on the first acoustic matching layer; a notch groove for dividing the first acoustic matching layer and a ground electrode of the piezoelectric vibrator into a plurality of pieces in a short axis direction; A connecting means for connecting each common ground electrode connected in common by the matching layer to the outside by a first acoustic matching layer on one or both ends in the scanning direction; and selectively switching the common ground electrode to form a short axis. An ultrasonic probe having switch means for variably controlling an acoustic aperture, wherein the width of the piezoelectric plate and the minor axis effective aperture length are the same, and each common ground electrode is selectively switched to provide a minor axis effective aperture. It has the effect of changing the length.

According to a seventh aspect of the present invention, a plurality of piezoelectric vibrators arranged in the scanning direction of ultrasonic waves, and a conductive first acoustic matching layer provided on the surface of the piezoelectric vibrators are provided. A second acoustic matching layer laminated on the first acoustic matching layer; a metal thin film layer provided between the first acoustic matching layer and the second acoustic matching layer; (1) a cut groove for dividing the acoustic matching layer and the ground electrode of the piezoelectric vibrator into a plurality of pieces in the short axis direction; and a common ground electrode commonly connected by the first acoustic matching layer and the metal thin film layer in the scanning direction. A connection means for connecting to the outside by a metal thin film layer at one or both ends or the first acoustic matching layer; and a switch means for selectively switching the common ground electrode to variably control a short-axis acoustic aperture. Ultrasonic probe that has a piezoelectric plate width and short axis effective With the same mouth length, each common ground electrode is switched selectively, has the effect of changing the minor axis effective aperture length.

Hereinafter, an embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIG.

(First Embodiment) In a first embodiment of the present invention, individual ground electrodes of a plurality of piezoelectric vibrators arranged in the scanning direction are arranged on the ground electrode surface of the piezoelectric vibrator. This is an ultrasonic probe which is connected in common by the provided conductive layers and takes out the ground electrode connected in common from one or both ends in the scanning direction.

FIG. 1 is a schematic perspective view of an ultrasonic probe according to a first embodiment of the present invention. In FIG. 1, a piezoelectric plate 1
Is a piezoelectric element that transmits and receives ultrasonic waves using piezoelectric ceramics such as PZT, polymers such as PVDF, and single crystals. Ground electrode 2 and signal electrode 3
Is an electrode formed by sputtering or plating gold or silver,
Alternatively, it is an electrode formed by baking silver on both opposing surfaces of the piezoelectric element.

The backing 4 is made of a material obtained by mixing microballoons or the like in ferrite rubber, epoxy, urethane rubber, or the like, and is a backing material for holding the piezoelectric plate 1 and absorbing unnecessary ultrasonic waves. The conductive acoustic matching layer 5 is made of a conductive material such as an epoxy resin or graphite to which an inorganic substance is added, and is an acoustic matching layer provided on the subject side of the piezoelectric plate 1 for efficiently transmitting ultrasonic waves. is there. The ground electrode 2 on the subject side of the piezoelectric plate 1 and the conductive acoustic matching layer 5 are electrically connected by a conductive adhesive. The acoustic matching layer 6 is made of a material such as an epoxy resin or a plastic material, and is an acoustic matching layer provided on the subject side of the conductive acoustic matching layer 5 for efficiently transmitting ultrasonic waves. In addition, in order to form the exposed portion 7 of the conductive acoustic matching layer at the end of the conductive acoustic matching layer 5 in the scanning direction, the acoustic matching layer 6 is longer than the conductive acoustic matching layer 5 in the scanning direction. Is short.

The channel dividing groove 8 is a dividing groove for dividing the piezoelectric plate 1 and forming a plurality of electrically independent piezoelectric vibrators 9. The ground electrode 2, the piezoelectric plate 1 and the signal electrode 3 are formed.
And a part of backing 4 is cut. The dividing groove 8 is mainly filled with a material such as silicone rubber, urethane rubber, and epoxy resin. The signal line 10 is a signal line taken out from the signal electrodes 2 of the plurality of piezoelectric vibrators 9.
The common ground electrode line 11 includes Cu, Au, Cr, Ag, Sn,
Ni is a metal foil, and is electrically connected to an exposed portion 7 formed at an end of the conductive acoustic matching layer 5 in the scanning direction by a conductive adhesive. It has a role of a common ground electrode electrically connected to the ground electrode 2 on the subject side of the piezoelectric vibrator 9 and is taken out from the same side as the signal line 10.

Although not shown, the acoustic lens provided on the subject side of the acoustic matching layer 6 is made of a material such as silicone rubber, urethane rubber, plastic, or the like, and is used for focusing ultrasonic waves. The side has a convex curved shape, and the opposite flat surface is bonded to the acoustic matching layer 6 with a silicone-based adhesive or epoxy resin.

In the ultrasonic probe according to the first embodiment shown in FIG. 1, the piezoelectric vibrators 9 are divided at equal intervals, and the silicone rubber or urethane rubber is formed in the channel dividing grooves 8 forming the channels. And fill with epoxy resin. The smaller the acoustic impedance of the material to be filled, the higher the independence of the divided piezoelectric vibrator and the wider the directional angle,
Since the mechanical strength is reduced, it is preferable to use an appropriate value. As a material to be filled in the dividing groove, in particular, silicone rubber or urethane rubber having an acoustic impedance of 1.0 to 2.5 Mrayl is desirable.

The operation of the ultrasonic probe configured as described above will be described. A plurality of electric signals transmitted from the transmission unit of the ultrasonic diagnostic apparatus main body (not shown) with arbitrarily delayed time timings are applied to the plurality of piezoelectric elements 9 via cables and signal lines 10. The piezoelectric element 9 to which the electric signal is applied generates ultrasonic waves, and the ultrasonic waves are radiated into the body of the patient via the conductive acoustic matching layer 5 and the acoustic matching layer 6 and the acoustic lens. The ultrasonic wave converges or deflects in the target direction of the scanning direction and propagates in accordance with the delay of the time timing from the transmission unit.

Ultrasonic waves are reflected according to the difference in acoustic impedance between the internal organ boundaries of the patient. The reflected ultrasonic waves are received by the piezoelectric vibrator 9 again, converted into electric signals, and transmitted to the receiving unit of the ultrasonic diagnostic apparatus main body via a cable. By processing the received signal and displaying the reflection image on the display unit of the ultrasonic diagnostic apparatus main body, the tomographic image of the inside of the patient can be confirmed. These operations are the same as those of the conventional ultrasonic probe, but other methods can be used as the ultrasonic transmission / reception method of the ultrasonic probe according to the first embodiment. .

Although the common ground electrode line 11 is taken out from one end in the scanning direction in FIG. 1, the common ground electrode line 11 may be taken out from both ends. The common ground electrode line 11 is taken out from the exposed portion of the end of the conductive acoustic matching layer 5 in the scanning direction on the same side as the signal line 10,
It may be taken out from the opposite side of the signal line 10 or the side surface in the scanning direction. As the common ground electrode line 11, a flexible printed board having a wiring pattern formed of a polymer material instead of a metal foil may be used.

In the first embodiment, the case where the number of the conductive acoustic matching layers 5 is one has been described. However, the number of the conductive acoustic matching plates 5 may be two or more. Although the conductive adhesive is used for bonding the ground electrode 2 and the conductive acoustic matching layer 5, an insulating epoxy resin adhesive may be used. In this case, in order to make the adhesive layer sufficiently thin, an adhesive pressure of 3
Add at least Kg / cm ² . The ground electrode 2 and the conductive acoustic matching layer 5 are partially contacted to connect the ground electrode 2 in common.

In the structure shown in FIG. 1, a channel dividing groove is formed by cutting a part of the piezoelectric plate and the backing. However, the channel is cut from the backing surface of the piezoelectric plate to a part of the conductive matching layer. A dividing groove may be formed.

As described above, in the first embodiment of the present invention, the ultrasonic probe is connected in common to the ground electrodes of the plurality of piezoelectric vibrators by the conductive acoustic matching layer, and is connected in the scanning direction. Since it is configured to be taken out from one or both ends, the short axis width of the piezoelectric plate can be shortened without shortening the short axis effective opening width, and the width of the patient contact part can be narrowed, such as intercostal scanning. Even from a narrow gap, it is possible to obtain a good ultrasonic tomographic image with a small reflected noise signal from the ribs.

Further, the effective aperture length can be increased with the same piezoelectric element width as the conventional one. If the short-axis effective aperture length is large, the area of the near-field becomes longer, and it is possible to diagnose deeper areas. Although improved, it is preferable to use the short-axis effective aperture width and the curvature of the acoustic lens according to the diagnostic site to be examined.

(Second Embodiment) In a second embodiment of the present invention, one or both ends in the scanning direction of the conductive acoustic matching layer electrically connected to the ground electrode of the piezoelectric plate. The conductive side plate is electrically connected to the exposed portion provided on the backing surface of the conductive acoustic matching layer with a conductive adhesive, and the common ground electrode of the plurality of piezoelectric vibrators arranged in the scanning direction is scanned. Is an ultrasonic probe taken out from the end of the probe. The second embodiment is different from the first embodiment in that a conductive side plate is used to extract a ground electrode from the conductive acoustic matching layer, and that the conductive acoustic matching layer is exposed on the backing side. The point is that the common ground electrode is taken out from the section.

FIG. 2 is a schematic sectional view in the scanning direction of an ultrasonic probe according to a second embodiment of the present invention. In FIG.
The ground electrode 2, signal electrode 3, backing 4, channel dividing groove 8, piezoelectric vibrator 9, and signal line 10 are the same as in the first embodiment.

The conductive acoustic matching layer 12 is longer than the length of the piezoelectric plate in the scanning direction, and is exposed on the backing surface at the end in the scanning direction.
14 are provided. The conductive side plate 15 is a conductive material mainly composed of an epoxy material or graphite to which an inorganic substance is added, and has an exposed portion 14 provided on a backing surface at an end in the scanning direction of the conductive acoustic matching layer 12. They are electrically connected by a conductive adhesive. The acoustic matching layer 13 is an acoustic matching layer provided on the subject side of the conductive acoustic matching layer 12 in order to efficiently transmit ultrasonic waves, and is made of a material such as an epoxy resin or a plastic material.

The acoustic lens 16 is made of a material such as silicone rubber, urethane rubber, or plastic, and is used to converge the ultrasonic waves. The subject has a convex curved surface, and the opposite flat surface has an acoustic matching layer. 13 is bonded with silicone adhesive or epoxy resin.

The operation of the ultrasonic probe configured as described above is the same as that of the first embodiment, and the description is omitted. In FIG. 2, the conductive side plates 15 are formed at both ends in the scanning direction, but may be formed at only one of the ends. FIG. 2 shows a case in which the conductive acoustic matching layer 12 is a single layer. However, the channel dividing groove 8 connects the ground electrode 2 of the piezoelectric vibrator 9 using the two conductive acoustic matching layers 12. The first conductive acoustic matching layer to be connected may be divided, and the second conductive matching plate may be used as a common ground electrode.

As described above, in the second embodiment of the present invention, the ultrasonic probe is connected to the conductive side plate and the conductive acoustic matching layer at the exposed portion of the conductive acoustic matching layer in the scanning direction. The width of the piezoelectric plate can be reduced without shortening the effective width of the short axis, the width of the patient contact area can be reduced, and the width of the space can be reduced from a narrow gap like intercostal scanning. In addition, it is possible to obtain a favorable ultrasonic tomographic image with little reflected noise signal from the ribs.

Further, it is also possible to increase the short-axis effective opening length with the same piezoelectric plate width as in the prior art. By installing the side plate having high hardness at the end in the scanning direction, it is possible to improve the impact resistance against the impact from the acoustic lens surface.

Further, even if the conductive side plate contacts the signal electrode at the end in the scanning direction or conducts with the conductive adhesive, the piezoelectric vibrator at the end does not contribute to the creation of an in-vivo image. Since it is a probe and is electrically independent of other piezoelectric vibrators and the channel dividing groove, there is no short circuit and the manufacture of the ultrasonic probe becomes easy.

(Third Embodiment) In a third embodiment of the present invention, a metal foil is provided on the side surface of the backing in the scanning direction, and the side surface of the metal foil and the conductive acoustic matching layer in the scanning direction is conductive. This is an ultrasonic probe which is electrically connected with a conductive adhesive to take out a common ground electrode of the piezoelectric vibrator from an end in the scanning direction. The third embodiment is different from the first and second embodiments in that no exposed portion is provided in the conductive acoustic matching layer, so that the common ground electrode can be easily taken out. This facilitates production.

FIG. 3 is a schematic sectional view in the scanning direction of an ultrasonic probe according to a third embodiment of the present invention. In FIG.
Piezoelectric plate 1, ground electrode 2, signal electrode 3, backing 4, channel dividing groove 8, piezoelectric vibrator 9, signal line 10
Is the same as in the first embodiment. The acoustic lens 16
This is the same as the second embodiment.

The conductive acoustic matching layer 17 has the same length as the length of the piezoelectric plate 1 in the scanning direction, is made of a conductive material such as epoxy resin or graphite to which an inorganic substance is added, and efficiently transmits ultrasonic waves. Therefore, the acoustic matching layer is provided on the subject side of the piezoelectric plate 1, and the ground electrode 2 on the subject side of the piezoelectric plate 1 and the conductive acoustic matching layer 17 are electrically connected by a conductive adhesive. . The acoustic matching layer 18 is made of a material such as an epoxy resin or a plastic material, and is an acoustic matching layer provided on the subject side of the conductive acoustic matching layer 17 for efficiently transmitting ultrasonic waves. The ground line 19 is a metal foil provided on the side of the backing 4 in the scanning direction.
Connected to 19 to take out the common ground electrode.

The operation of the ultrasonic probe configured as described above is the same as in the first embodiment, and a description thereof will be omitted. In FIG. 3, the ground lines 19 are formed at both ends in the scanning direction, but may be formed at only one of the ends. FIG. 3 shows a case where the conductive acoustic matching layer 17 is a single layer. However, the channel dividing groove 8 is connected to the ground electrode of the piezoelectric vibrator 9 using two conductive acoustic matching layers. The first conductive acoustic matching layer is divided, and the second conductive acoustic matching layer is used as a common ground electrode, and the side surface in the scanning direction of the second conductive acoustic matching layer is connected to the ground line with a conductive adhesive. Then, the common ground electrode may be taken out.

As described above, in the third embodiment of the present invention, the ultrasonic probe is configured such that the common ground electrode is taken out from the side of the conductive acoustic matching layer in the scanning direction.
The length of the conductive acoustic matching layer and the acoustic matching layer in the scanning direction can be the same as the length of the piezoelectric plate, which facilitates fabrication.

Further, since the width of the piezoelectric plate can be reduced without shortening the effective opening width of the short axis, the width of the patient contact portion can also be reduced, and scanning is performed from a narrow gap like intercostal scanning. Even in this case, a good tomographic image of an ultrasonic wave with less reflected noise signals from the ribs can be obtained. It is also possible to increase the short-axis effective opening length with the same short-axis width of the piezoelectric plate as before.

(Fourth Embodiment) In a fourth embodiment of the present invention, a plurality of piezoelectric vibrators arranged in the scanning direction are provided with electrode bodies at both ends in the scanning direction. An ultrasonic probe in which ground electrodes are commonly connected by a conductive acoustic matching layer provided on a subject side on a plurality of piezoelectric transducer surfaces including the above, and a common ground electrode is taken out from the electrode body. 4th
This embodiment is different from the first to third embodiments in that an electrode body for extracting a ground electrode is provided.

FIG. 4 is a schematic sectional view in the scanning direction of an ultrasonic probe according to a fourth embodiment of the present invention. Piezoelectric plate 1,
The backing 4, the channel dividing groove 8, the piezoelectric vibrator 9, and the signal line 10 are the same as in the first embodiment. Acoustic lens
16 is the same as in the second embodiment. The conductive acoustic matching layer 17 and the acoustic matching layer 18 are the same as in the third embodiment.

A ground electrode 22 and a signal electrode 23 are formed on two opposing surfaces of the piezoelectric plate 1. Ground electrode
The electrode 22 and the signal electrode 23 are electrodes formed by sputtering or plating gold or silver, or electrodes formed by baking silver or the like. The ground electrode 22 and the signal electrode 23 are electrically separated from each other. The ground line 19 is formed of a conductive metal, silicone rubber, urethane rubber, or the like formed on the conductive acoustic matching layer 17 and the end of the piezoelectric plate 1 in the scanning direction.
It is electrically connected to the ground electrode 22 of each piezoelectric vibrator 9 separately via an electrode body 33 made of epoxy or the like.

The operation of the ultrasonic probe configured as described above is the same as in the first embodiment, and will not be described. In FIG. 4, the ground line 19 is taken out from the same side as the signal line 10, but may be taken out from the opposite side of the signal line 10 or the side surface at the end in the scanning direction. The ground line 19 is taken out from both ends in the short axis direction, but may be provided on only one side.

As described above, in the fourth embodiment of the present invention, the ultrasonic probe is connected to the ground electrode by the conductive acoustic matching layer in common, and is provided at the both ends in the scanning direction. Since the common ground electrode is taken out from the body, the width of the piezoelectric plate can be shortened and the width of the patient contact area can be reduced without shortening the effective aperture width of the short axis. Even in the case of the scanning, it is possible to obtain a favorable ultrasonic tomographic image with a small reflected noise signal from the ribs. It is also possible to increase the short-axis effective opening length with the same short-axis width of the piezoelectric plate as before.

(Fifth Embodiment) In a fifth embodiment of the present invention, the grounding electrode is formed on a part of the signal electrode surface via the side surface at the end in the scanning direction. Are ultrasonic probes which are commonly connected by a conductive acoustic matching layer, and which take out a common ground electrode from a ground electrode wound around a backing surface. The fifth embodiment differs from the first to fourth embodiments in that a grounding electrode is provided through the side surface of the piezoelectric plate in the scanning direction.

FIG. 5 is a schematic sectional view in the scanning direction of an ultrasonic probe according to a fifth embodiment of the present invention. Also, FIG.
It is an electrode formation figure of the piezoelectric plate of the ultrasonic probe of a 5th embodiment. In FIG. 5, a backing 4, a channel dividing groove 8, and a signal line 10 are the same as those in the first embodiment. The acoustic lens 16 is the same as in the second embodiment. The conductive acoustic matching layer 17 and the acoustic matching layer 18 are the same as in the third embodiment.

The piezoelectric plate 21 is formed with a ground electrode 22 and a signal electrode which are turned from the side surface at the end in the scanning direction on two opposing surfaces. Ground electrode 22 and signal electrode
Reference numeral 23 denotes an electrode formed by sputtering or plating gold or silver, or an electrode formed by baking silver or the like.
A groove 24 is formed in the piezoelectric plate 21 so that the ground electrode 22 and the signal electrode 23 do not short-circuit. Since no electrode is formed in the groove 24 and the piezoelectric plate 21 is exposed, the ground electrode 22 and the signal electrode 23 are electrically separated from each other.

The ground line 19 is connected to the piezoelectric plate 21 at the end in the scanning direction via the conductive acoustic matching layer 17 electrically connected to the ground electrode 22 of each of the piezoelectric vibrators 9 separated from each other.
And is electrically connected to the ground line 19 from the backing side of the piezoelectric plate 21.

The operation of the ultrasonic probe configured as described above is the same as in the first embodiment, and will not be described. In FIG. 5, the ground line 19 is taken out from the same side as the signal line 10, but may be taken out from the opposite side of the signal line 10 or the side surface at the end in the scanning direction. The ground line 19 is taken out from both ends in the short axis direction, but may be provided only on one side. In FIGS. 5 and 6, the ground electrode 22 of the piezoelectric plate 21 is turned from both ends in the scanning direction to the opposite surface, but may be provided on only one side. Further, in FIG. 5, the electrodes on one surface of the piezoelectric plate 21 are formed as a turn-around electrode. However, solid ground electrodes and signal electrodes are formed on both surfaces, and conductive electrodes are formed on the side surfaces at the ends in the scanning direction. The signal electrode on the backing side and the common ground electrode on the surface of the acoustic lens are electrically connected with an adhesive, and the end portion of the piezoelectric vibrator 9 is electrically separated from the signal electrode 23 of the piezoelectric vibrator 9 except for the end portion by a channel dividing groove. The signal electrode 23 of the vibrator and the ground line 19 may be electrically connected.

As described above, in the fifth embodiment of the present invention, the ultrasonic probe is configured to turn the ground electrode on the subject side to a part of the signal electrode via the side surface at the end in the scanning direction. Thus, the ground wire can be taken out from the backing side of the piezoelectric plate without being electrically connected to the conductive acoustic matching layer by the conductive side plate or the metal foil.

Further, by using one printed circuit board on which an arrangement pattern of signal lines and ground lines is formed, production can be easily performed and the number of parts can be reduced. Since the short-axis width and short-axis effective opening width of the piezoelectric plate can be made the same, the width of the patient contacting part can also be narrowed, and even from narrow gaps such as intercostal scanning, there are few reflected noise signals from the ribs, good It becomes possible to obtain a tomographic image of an ultrasonic wave. The effective aperture length can be increased with the same piezoelectric element width as that of the related art.

(Sixth Embodiment) In a sixth embodiment of the present invention, the conductive acoustic matching layer, the piezoelectric plate, and a part of the backing are separated by a channel dividing groove, and the ground electrode of the piezoelectric plate is A ground electrode is connected to the outside via a conductive side plate electrically connected to the conductive acoustic matching layer and the metal thin film layer via a conductive side plate electrically connected at an end of the conductive acoustic matching layer in the scanning direction. It is an ultrasonic probe. The sixth embodiment is the first
The difference from the fifth embodiment is that the conductive acoustic matching layer is also separated by the channel dividing groove to increase the independence of the channel.

FIG. 7 is a schematic sectional view parallel to the scanning direction of an ultrasonic probe according to a fifth embodiment of the present invention. In FIG. 7, a piezoelectric plate 1, a ground electrode 2, a signal electrode 3,
The backing 4 and the signal line 10 are the same as in the first embodiment. The conductive acoustic matching layer 12, acoustic matching layer 13, conductive side plate 15, and acoustic lens 16 are the same as in the second embodiment.

The channel dividing groove 25 is formed of a conductive acoustic matching layer.
12 is a cut groove obtained by cutting a part of the piezoelectric plate 1 and the backing 4, and the groove is filled with epoxy resin, silicone rubber, or urethane rubber. The metal thin film layer 26 is made of C
It is a thin film of 20 μm or less made of u, Ag, Au, Cr, Ni, Ti, and Sn, which is electrically connected to the subject side of the conductive acoustic matching layer 12 by a conductive adhesive or an insulating epoxy adhesive. I have. When bonding with an insulating epoxy adhesive, a bonding pressure of 3 kg / cm ² or more is applied to sufficiently reduce the thickness of the bonding layer. The conductive state can be obtained by bringing the conductive acoustic matching layer 12 and the metal thin film layer 26 into partial contact. The ground electrodes 2 of the plurality of piezoelectric vibrators 9 arranged in the scanning direction are:
It is electrically connected to the conductive acoustic matching layer 12 via the metal thin film layer 26. The conductive side plate 15 electrically connected to the scanning direction end of the conductive acoustic matching layer 12 and the metal thin film layer 26 serving as a common ground electrode are electrically connected to form a common ground for each piezoelectric vibrator 9. doing.

The operation of the ultrasonic probe configured as described above is the same as that of the first embodiment, and the description is omitted. In FIG. 7, the ground electrode 2 is taken out using the conductive side plate 15 connected to the end of the conductive acoustic matching layer 12 on the backing side in the scanning direction. However, in the first embodiment and the third embodiment, As in the embodiment, the piezoelectric plate may be taken out with a metal foil, or a piezoelectric plate on which a wrap-around electrode is formed through an end in the scanning direction. The metal thin film layer 26 is an acoustic matching layer.
Gold or silver may be formed on the surface of the backing side of 13 by sputtering or plating.

As described above, in the sixth embodiment of the present invention, since the ultrasonic probe has a configuration in which the piezoelectric plate and the conductive acoustic matching layer are separated, the independence of the piezoelectric vibrator is improved. Therefore, an ultrasonic wave having a wide directional characteristic can be transmitted, and the width of the piezoelectric plate and the width of the short-axis effective aperture can be made the same, thereby improving operability.

(Seventh Embodiment) In a seventh embodiment of the present invention, the conductive acoustic matching layer, the metal thin film layer, and the ground electrode of the piezoelectric vibrator are divided into a plurality in the short axis direction. The common ground electrode is connected in common and taken out from the metal thin film layer or conductive acoustic matching layer at the end, and the common ground electrode is selectively switched by a switch, and the ultrasonic probe that variably controls the short-axis acoustic aperture is used. is there. The seventh embodiment is the first to
The difference from the sixth embodiment is that the divided ground electrode is selectively switched by a switch.

FIG. 8 is a perspective view of an essential part of an ultrasonic probe according to a seventh embodiment of the present invention. 8, a piezoelectric plate 1, a ground electrode 2, a signal electrode 3, a backing 4,
The channel dividing groove 8 and the piezoelectric vibrator 9 are the same as in the first embodiment.

The conductive acoustic matching layer 27 is made of a conductive material such as an epoxy resin or graphite to which an inorganic substance is added. The acoustic matching layer 27 is provided on the subject side of the piezoelectric plate 1 for efficiently transmitting ultrasonic waves. The ground electrode 2 on the subject side of the piezoelectric plate 1 and the conductive acoustic matching layer 5 are electrically connected by a conductive adhesive. The acoustic matching layer 28 is a material such as an epoxy resin or a plastic material, and is an acoustic matching layer provided on the subject side of the conductive acoustic matching layer 27 for efficiently transmitting ultrasonic waves. An exposed portion 29 is formed on the subject side at the end of the conductive acoustic matching layer 27 in the scanning direction. Also,
The acoustic matching layer 28 is shorter than the length of the conductive acoustic matching layer 27 in the scanning direction in order to form the exposed portion 29. The common ground dividing groove 30 divides a common ground of the conductive acoustic matching layer 27 electrically connected to the ground electrodes 2 of the plurality of piezoelectric vibrators 9 in a short axis direction, and a plurality of electrically independent common grounds. An electrode is formed and is electrically independent of an adjacent common ground electrode, and is a groove formed by cutting the conductive acoustic matching layer 27 and the acoustic matching layer. The interior of the common ground dividing groove 30 is filled with epoxy resin, silicone rubber, urethane rubber, or the like. The common ground dividing groove 30 is cut from the acoustic matching layer 28 to a part of the piezoelectric plate 1 and is divided into a plurality in the short axis direction to form a plurality of electrically independent common ground electrodes. ing.
The common ground line 19 is a flexible printed circuit board or a copper foil, is electrically connected to the exposed portion 29 of the conductive acoustic matching layer 27 by a conductive adhesive, and is taken out from the side surface at the end in the scanning direction. The switch means 32 is connected to the common ground line 19 extracted from a plurality of common ground electrodes arranged in the short axis direction, and selectively switches the short axis of ultrasonic wave reception and transmission of the piezoelectric plate. The effective aperture width can be controlled.

The operation of the ultrasonic probe configured as described above will be described with reference to FIGS. FIG. 9 is a cross-sectional view in the minor axis direction of an ultrasonic probe according to the seventh embodiment of the present invention. The plurality of electric signals transmitted from the transmitting section of the ultrasonic diagnostic apparatus main body (not shown) are arbitrarily delayed and applied to the plurality of piezoelectric vibrators 9 via cables and signal lines 10. . The piezoelectric vibrator 9 to which the electric signal is applied generates an ultrasonic wave, and is transmitted through the conductive acoustic matching layer 5, the acoustic matching layer 6, and the acoustic lens 16 into the patient's body due to a time delay from the transmitting unit. The ultrasonic wave is converged or deflected in the scanning direction to propagate the ultrasonic wave. At this time, each common ground electrode independent of each other can be controlled by the switch means 32 by the common ground dividing groove 30 to control the short-axis effective opening width. By controlling the short-axis effective aperture length, for example, at short distances,
The resolution can be improved by narrowing the short-axis opening length.
The ultrasonic wave reflected from the difference in acoustic impedance between the internal organs of the patient is received again by the piezoelectric vibrator 9 while changing the focal point by selectively switching the common ground line 19 in the same manner as described above. After being converted into an electric signal, the signal is transmitted to a receiving unit of the ultrasonic diagnostic apparatus main body via a cable. By processing the received signal and displaying the reflection image on the display unit of the ultrasonic diagnostic apparatus main body, the tomographic image of the inside of the patient can be confirmed.

In FIG. 8, the same configuration as that of the first embodiment is used as a method of taking out the common ground.
In addition to the above configuration, the present invention can be implemented using the configurations described in the second, third, fourth, fifth, and sixth embodiments. In FIG. 8, the acoustic matching layer, the conductive acoustic matching layer, and the ground electrode of the piezoelectric plate are cut to divide the common ground electrode. However, in order to increase the strength against impact, the second matching plate is cut. It may be configured not to be cut. In FIG. 8, a convex curved surface is formed on the subject side of the acoustic lens, but the thickness of the acoustic lens may be uniform. Instead of controlling the symmetric common ground electrode as shown in FIGS. 8 and 9, the connection may be asymmetrically connected or switched individually.

As described above, in the seventh embodiment of the present invention, the ultrasonic probe divides the common ground electrode in the short axis direction and selectively connects a plurality of common ground electrodes by the switch means. With this configuration, it is possible to control the effective aperture width of the short axis, and to provide an ultrasonic probe with excellent lateral resolution in the short axis direction and excellent operability at short distances. it can.

[0068]

As described above, according to the present invention, the ultrasonic probe is connected to the ground electrode on the subject side of the two opposing electrodes of the polarized piezoelectric plate in the ultrasonic scanning direction. The width of the piezoelectric vibrator is reduced, the operability is improved, and the effective short axis width of the ultrasonic wave radiated from the piezoelectric plate can be increased. Even in the case of scanning from a narrow gap as described above, an effect is obtained that a favorable ultrasonic tomographic image with few reflected noise signals from the ribs can be displayed.

Further, the ultrasonic probe is divided by making a plurality of cuts in the short axis direction of the common ground electrode of the piezoelectric vibrator, and each common ground electrode is selectively switched by a switch. By changing the axial effective aperture width, an optimum beam is formed in accordance with the measurement area, thereby improving the azimuth resolution at a short distance and improving penetration even at a long distance.

[Brief description of the drawings]

FIG. 1 is a perspective view of a main part of an ultrasonic probe according to a first embodiment of the present invention,

FIG. 2 is a schematic sectional view in the scanning direction of an ultrasonic probe according to a second embodiment of the present invention;

FIG. 3 is a schematic sectional view of an ultrasonic probe in a scanning direction showing a third embodiment of the present invention;

FIG. 4 is a schematic sectional view in the scanning direction of an ultrasonic probe according to a fourth embodiment of the present invention;

FIG. 5 is a schematic sectional view in the scanning direction of an ultrasonic probe according to a fifth embodiment of the present invention;

FIG. 6 is an electrode configuration diagram of a piezoelectric plate of an ultrasonic probe according to a fifth embodiment of the present invention;

FIG. 7 is a schematic cross-sectional view parallel to a scanning direction of an ultrasonic probe according to a sixth embodiment of the present invention;

FIG. 8 is an essential part perspective view of an ultrasonic probe showing a seventh embodiment of the present invention;

FIG. 9 is a cross-sectional view of an ultrasonic probe according to a seventh embodiment of the present invention in a short-axis direction,

FIG. 10 is a schematic perspective view of a conventional ultrasonic probe.

[Explanation of symbols]

 1, 21, 50 Piezoelectric plate 2, 22, 55 Ground electrode 3, 23, 57 Signal electrode 4, 54 Backing 5, 12, 17, 27 Conductive acoustic matching layer 6, 13, 18, 28 Acoustic matching layer 7, 14 , 29 Exposed part 8, 25, 59 Channel division groove 9, 60 Piezoelectric vibrator 10 Signal line 11, 19 Common ground line 15 Conductive side plate 16, 53 Acoustic lens 20 Conductive adhesive 24, 61 Groove 26 Metal thin film layer 30 Common ground dividing groove 32 Switch means 33 Electrode body 51 First matching plate 52 Second matching plate 56 Copper foil 58 Printed circuit board

Claims (7)

[Claims] 1. A plurality of piezoelectric vibrators arranged in a scanning direction of an ultrasonic wave, a conductive layer commonly connecting a ground electrode of the piezoelectric vibrator, and the ground electrode interposed in the scanning direction via the conductive layer. Connecting means for connecting to the outside at one or both ends of the ultrasonic probe. 2. The ultrasonic probe according to claim 1, wherein the conductive layer is a conductive acoustic matching layer provided on the ground electrode surface. 3. The conductive layer is a conductive first acoustic matching layer provided on a ground electrode surface of the piezoelectric vibrator, and a metal thin film layer laminated on the first acoustic matching layer. The connection means is means for connecting one or both ends of the metal thin film layer or the first acoustic matching layer in one or both sides in the scanning direction to the outside, and has a second acoustic matching layer laminated on the metal thin film layer. The ultrasonic probe according to claim 1, wherein: 4. An electrode body arranged adjacent to the piezoelectric vibrator at one or both ends in a scanning direction, and the conductive layer is provided on the object side of the electrode body and the piezoelectric vibrator. 4. The ultrasonic probe according to claim 1, wherein the at least one conductive acoustic matching layer is provided, and the connecting means is a means for connecting the electrode body to the outside. . 5. A signal electrode and a ground electrode are respectively formed on two opposing surfaces of the piezoelectric vibrator, and a ground electrode is formed on a part of the signal electrode surface via an end side surface in the scanning direction. 3. A piezoelectric vibrator, wherein said connecting means is means for connecting a ground electrode turned around to a signal electrode surface at one or both ends in a scanning direction to the outside. 3. The ultrasonic probe according to 3, 4 or 5. 6. A plurality of piezoelectric vibrators arranged in a scanning direction of an ultrasonic wave, a first conductive acoustic matching layer provided on the surface of the piezoelectric vibrator, and a laminate on the first acoustic matching layer. A second acoustic matching layer, a cut groove that divides the first acoustic matching layer and the ground electrode of the piezoelectric vibrator into a plurality of pieces in a short axis direction, and a common groove connected in common by the first acoustic matching layer. Connecting means for connecting the ground electrode to the outside at a first acoustic matching layer at one or both ends in the scanning direction; and switch means for selectively switching the common ground electrode to variably control the short-axis acoustic aperture. An ultrasonic probe comprising: an ultrasonic probe; 7. A plurality of piezoelectric vibrators arranged in a scanning direction of ultrasonic waves, a conductive first acoustic matching layer provided on the surface of the piezoelectric vibrator, and a plurality of piezoelectric vibrators stacked on the first acoustic matching layer. Second acoustic matching layer, a metal thin film layer provided between the first acoustic matching layer and the second acoustic matching layer, the metal thin film layer, the first acoustic matching layer, and the piezoelectric vibrator. And a notch groove for dividing the ground electrode into a plurality of pieces in the minor axis direction, and connecting the common ground electrodes commonly connected by the first acoustic matching layer to the metal thin film layer or the metal thin film layer on one or both ends in the scanning direction. (1) An ultrasonic probe comprising: connection means for connecting to the outside with one acoustic matching layer; and switch means for selectively switching the common ground electrode to variably control a short-axis acoustic aperture.