JP3380190B2 - Ultrasonic probe - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic probe used for a sonar, an ultrasonic diagnostic apparatus and the like, and more particularly to an ultrasonic probe having high electromagnetic wave resistance.

[0002]

2. Description of the Related Art As a conventional ultrasonic probe, one having a structure described in, for example, Japanese Patent Laid-Open No. 9-84194 is known. FIG. 7 shows a conventional ultrasonic probe. In this ultrasonic probe, an ultrasonic transducer 101 includes a piezoelectric transducer 102 that converts an electric signal into mechanical vibration to radiate an ultrasonic wave, and that receives an ultrasonic wave and converts the electric signal into an electric signal. It is composed of a first electrode 103 and a second electrode 104 for exchanging electric signals with the vibrator 102. The first electrode 103 is provided so as to cover the front surface of the piezoelectric vibrator 102, that is, the ultrasonic wave transmitting / receiving surface, the end portion of the side surface in one direction, and a part of the back surface. The second electrode 104 is provided on the back surface of the piezoelectric vibrator 102 in a state of being electrically separated from the first electrode 103.

A first acoustic matching layer 105 and a second acoustic matching layer 106 are provided on the front surface of the ultrasonic transducer 101. Further, although not shown, an acoustic lens for focusing ultrasonic waves is provided on the front surface of the second acoustic matching layer 106. The ends of the first signal line 107 and the second signal line 108 are electrically connected to the first electrode 103 and the second electrode 104 at both ends on the back side of the ultrasonic transducer 101 by soldering or a conductive adhesive. Are electrically connected to each other so that an electric signal can be transmitted / received to / from an external device.

On the back surface of the ultrasonic vibrator 101 is a back load material 109.
Are formed. The back load material 109 is formed in advance by a method such as being molded and bonded to the back surface of the ultrasonic transducer 101, or being cured by pouring an uncured thermosetting resin.

The operation of the conventional ultrasonic probe configured as described above will be described. Electrical signals of a plurality of channels transmitted from a transmitter of an external device (not shown) such as an ultrasonic diagnostic apparatus main body are transmitted via a cable (not shown) and the first signal line 107 and the second signal line 108. It is applied to a part of the channel group of the piezoelectric vibrator 102. The piezoelectric vibrator group to which the electric signal is applied generates ultrasonic waves, and through the first acoustic matching layer 105, the second acoustic matching layer 106, and an acoustic lens (not shown),
It is transmitted to a subject such as a living body. The ultrasonic waves transmitted to the inside of the subject are reflected at the boundary where there is a difference in the acoustic impedance of the tissues inside the subject, and are received again by the piezoelectric transducer group. The channels are electronically operated to sequentially transmit and receive ultrasonic waves. These received signals are processed by an external device,
By displaying an image on the display unit, a tomographic image of the subject can be obtained.

[0006]

However, in the above-mentioned conventional ultrasonic probe, since the electromagnetic wave radiation surface is not shielded against electromagnetic waves, there is a strong electromagnetic wave generation source outside. In particular, when the frequency is 1 MHz to 20 MHz including diagnostic information, the ultrasonic transducer may receive the noise, and it is necessary to pay attention to the deterioration of the diagnostic performance such as the appearance of noise in the diagnostic image. .

In the conventional ultrasonic transducer 101, the first electrode 103 and the second electrode 104, the first signal line 107 and the second signal line 108 electrically connected to the first electrode 103 and the second electrode 104, and these A ring (hereinafter referred to as a signal line loop) in a region surrounding the point where the first signal line 107 and the second signal line 108 are closest to each other on the back side of the back load material 109 (hereinafter referred to as a signal line loop) functions as an antenna, so that it is easy to receive electromagnetic waves. there were. In particular, for a low frequency probe having a lower center frequency, it is necessary to increase the width of the piezoelectric vibrator in order to form a focal point further away, and as a result, the signal line loop becomes larger. Further, in a convex type diagnostic ultrasonic probe having a wide diagnostic field, the back load material has a curvature shape, so that the piezoelectric vibrator is
The thickness of the back load material or the thickness of the hard material or the like provided on the back side of the back load material for the purpose of holding the back load material increases, so that the signal line loop becomes large. And when the signal line loop becomes large, it becomes easier to receive electromagnetic waves,
That is, there is a problem that the electromagnetic wave resistance becomes low.

The present invention has been made to solve such a conventional problem, and an object thereof is to provide an ultrasonic probe having improved electromagnetic wave immunity.

[0009]

An ultrasonic probe of the present invention is a piezoelectric vibrator, a first electrode provided on the front surface of the piezoelectric vibrator, and a first electrode provided on the back surface of the piezoelectric vibrator. Two electrodes, a first signal line electrically connected to the first electrode and extended to the outside, and a second signal line electrically connected to the second electrode and extended to the outside are provided. Prepare, in front
The first signal line functions as a ground, and the piezoelectric vibration
The first signal line and the second signal line are taken out from both sides of the pendulum .
A signal line is electrically connected to at least one of a coaxial cable, a printed wiring board, or a connector pin for connecting to the coaxial cable on the back side of the back load material, and the first signal line and the first signal line. A signal formed by the closest contact point, the first signal line, the first electrode, the second electrode, and the second signal line, which is the closest contact point at a position where the two signal lines are connected. The area of the line loop is set to 1/1000 mm ² or more and 160 mm ² or less. With this configuration, between the first signal line and the first electrode
The electric resistance of the
It is possible to reduce the electromotive force generated in the case of Also,
It is possible to improve the electromagnetic wave resistance and prevent the influence of noise due to electromagnetic waves in the 1 to 20 MHz band.

[0010]

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to FIGS.

FIG. 1 is a partial schematic sectional view of an ultrasonic probe according to a first embodiment of the present invention. As shown in this figure, in the first embodiment of the present invention, the first signal line and the second signal line are led out from the side surface on the same side of the piezoelectric vibrator in the vertical direction of the back surface, and from the first electrode. The area of the signal line loop was reduced by configuring the piezoelectric vibrators to be closest to each other at a position within a distance of twice the width of the piezoelectric vibrator.

This ultrasonic probe comprises a piezoelectric vibrator 1, a first electrode provided on the front surface of the piezoelectric vibrator 1, a second electrode provided on the back surface of the piezoelectric vibrator 2, and a first electrode. First acoustic matching layer 5 and second acoustic matching layer 6 provided on the front surface of
A first signal line 7 electrically connected to the first electrode 2 and drawn to the outside, and a second signal line 8 electrically connected to the second electrode 3 and drawn to the outside, The back load member 4 provided on the back surface of the second electrode 3 is provided. Although not shown, an acoustic lens is provided on the front surface of the second acoustic matching layer 6.

The piezoelectric vibrator 1 is a piezoelectric element that transmits and receives ultrasonic waves using a piezoelectric ceramic such as a PZT system, a single crystal, and a polymer such as PVDF. First electrode 2
The second electrode 3 is an electrode formed by sputtering gold or silver or plating, or an electrode formed by baking silver or the like. The back load member 4 is made of a material in which micro balloons are mixed with ferrite rubber, epoxy, urethane rubber, etc., and has a function of holding the piezoelectric vibrator 1 and absorbing unnecessary ultrasonic waves. The first acoustic matching layer 5 is made of glass, an epoxy resin mixed with a filler,
Alternatively, it is an acoustic matching layer provided on the surface of the piezoelectric vibrator 1 on the side opposite to the back load material 4 in order to efficiently propagate ultrasonic waves using a material such as graphite. Second acoustic matching layer 6
Is an acoustic matching layer having the same function as the first acoustic matching layer 5 provided on the subject side, using an epoxy resin, a plastic material, or the like. The first signal line 7 is a signal line that is electrically connected to the first electrode 2 on the subject side of the piezoelectric vibrator 1 with solder, a conductive adhesive material, or the like. Second signal line 8
Is a signal line electrically connected to the second electrode 3 on the back load member 4 side of the piezoelectric vibrator 1 by solder or a conductive adhesive. The first signal line 7 and the second signal line 8 are taken out from the same end of one of the first electrode 2 and the second electrode 3 of the piezoelectric vibrator 1, and arranged in parallel along the side surface of the back load material 4. Has been done. The closest contact 9 indicates the location where the first signal line 7 and the second signal line 8 are closest to each other. The closest contact 9 has the smallest distance, such as a connection with a coaxial cable (not shown) or a connection with a printed wiring board (not shown) on which a ground and a signal pattern are formed. Here, the first electrode 2 and the first signal line 7 are at ground potential,
The second electrode 3 and the second signal line 8 have a potential for an AC signal.

In FIG. 1, the width of the piezoelectric vibrator 1 is
W1 and its thickness are represented by T1. The distance T3 from the front end of the first electrode 2 to the closest contact 9 is set to be twice W1 or less.

FIG. 2 is a diagram for explaining a signal line loop in the ultrasonic probe shown in FIG. In this figure, the same parts as those in FIG. 1 are designated by the same reference numerals as those used in FIG. Further, in this figure, the first signal line 7
The distance between the second signal line 8 and the second signal line 8 is represented by W2, and the length of the first signal line 7 in the front-rear direction is represented by T2. Further, the area S of the signal line loop is represented by a crossed diagonal line. As is clear from this figure, the closest contact point 9, the first signal line 7, the first electrode 2, the side surface of the piezoelectric vibrator 1 on the side where the signal line is not drawn out, the second electrode 3, The area surrounded by the two signal lines 8 forms a signal line loop.

In FIG. 2, the distance W2 between the first signal line 7 and the second signal line 8 is shortened, or the back load member 4 is used.
It is desirable to shorten the distance T2 from the first electrode 2 of the piezoelectric vibrator 1 to the closest contact 9 by reducing the thickness of the piezoelectric vibrator 1. If these distances are sufficiently short with respect to the wavelength of the electromagnetic wave, when electromagnetic waves from the outside enter, even if the electric field and magnetic force lines of the electromagnetic wave cross the signal line loop surface, the distance between the opposite sides of the signal line loop is short. The difference between the electric fields intersecting each other and the strength of the lines of magnetic force becomes smaller, so that the generated electromotive force becomes smaller. Further, since the length of each side of the signal line loop is shortened, the portion affected by the electromagnetic wave is reduced, so that the sensitivity to the electromagnetic wave can be reduced. Radiation of electromagnetic waves can be reduced by the same effect.

A method of measuring the electromagnetic wave immunity will be described with reference to FIG. FIG. 3 is a diagram for explaining a method of measuring the electromagnetic wave immunity of the ultrasonic probe alone. This measuring method includes a sensor unit 20 for transmitting and receiving ultrasonic waves, a cable unit 21 for transmitting signals, and an ultrasonic probe 23 including a connector unit 22 connected to an external device body (not shown), Ultrasonic probe
This is performed using a metal box 24 for preventing electromagnetic wave interference to a portion other than a specific portion of 23 and a loop coil 25 that radiates an electromagnetic wave to a specific portion of the ultrasonic probe 23.

To measure the electromagnetic wave immunity, a high frequency voltage is applied to the loop coil 25, and the ultrasonic wave is passed over the ultrasonic wave emitting surface of the ultrasonic probe 23. At this time, the electromotive force generated by the electromagnetic wave is applied to the ultrasonic probe 23. Measure from the connector section 22. Loop coil 25
When the input voltage applied to is set to Vin, a specific channel group of the connector section 22 of the ultrasonic probe 23 is electrically connected in parallel, and the measured output voltage is set to Vout, the ultrasonic probe
Electromagnetic wave immunity Gain of specific part of 23 is 20 × log (Vout / Vin)
Is represented by.

FIG. 4 shows the signal line loop area S and the electromagnetic wave immunity.
It is a characteristic view which shows the relationship with Gain. This characteristic diagram is shown in Fig. 3.
This is derived from the measurement results of the actual signal line area and the electromagnetic wave immunity of the ultrasonic probe, using the measurement method described in. From this characteristic diagram, it is understood that the electromagnetic wave resistance of the ultrasonic probe is improved as the signal line loop area is reduced.

Here, in order to explain the comparison result of the electromagnetic wave immunity of the conventional ultrasonic probe and the ultrasonic probe of the first embodiment of the present invention, a concrete example of the conventional ultrasonic probe will be described. Such a structural example and electromagnetic wave immunity will be described with reference to FIG.

FIG. 8 shows a concrete configuration example of a conventional ultrasonic probe. The width W1 of the piezoelectric vibrator 102 is 14.1 mm, and the thickness T
1 is 0.37 mm. The first electrode 10 on the back side of the piezoelectric vibrator 102
The gap distance between 3 and the second electrode 104 is 1 mm. The first signal line 107 and the second signal line 108 have a width W3 of 14.5 mm and a thickness T4.
Is set to 25.3 mm and is drawn out so as to surround the back load material 109 from the opposite surfaces of the back load material 109 facing each other. further,
The first signal line 107 and the second signal line 108 are electrically connected to the coaxial cable or the printed wiring board on the back side of the back load material 109 and have the shortest distance. At this time, the first signal line 10
Place where 7 and second signal line 108 are closest to each other (closest contact point) 110
From the first signal line 107, the first electrode 103 and the second electrode 104
The area of the smallest region surrounded by the second signal line 108 was about 372 mm ² , as shown in FIG. At this time, as a result of measuring the electromagnetic wave immunity of the ultrasonic radiation surface by the measuring method shown in FIG. 3, the characteristics shown in A of FIG. 5 were obtained. From this characteristic, the electromagnetic wave immunity is 1MHz to 20MHz,
The worst value was -52 dB.

If the minimum value of the electromagnetic wave immunity is improved by 10 dB with respect to the characteristic of the conventional example shown in FIG.
Generation of noise due to electromagnetic waves in the band of up to 20 MHz is extremely rare, and it is at a level at which an ultrasonic diagnostic apparatus does not cause misdiagnosis due to noise when diagnosing ultrasonic images. The conventional structure of the immunity force, that is, the signal loop area improve about 10dB or more to about 350 mm ^2, the characteristic diagram of FIG. 4, required that the signal line loop area S is about 160 mm ² or less I understand that it will be done.

In order to meet this requirement, the distance between the first signal line and the second signal line is reduced, or the thickness of the back load material is reduced so that the back surface of the back load material is removed from the electrodes of the piezoelectric vibrator. The distance to the point where the first signal line and the second signal line are closest to each other is shortened. If this distance is sufficiently short with respect to the wavelength of the electromagnetic wave, when the electromagnetic wave from the outside enters, the electric field of the electromagnetic wave and the magnetic field lines intersect the signal line loop surface, but the shorter the distance between the opposite sides of the signal line loop, the shorter the distance. As a result, the difference between the intersecting electric field and the strength of the lines of magnetic force becomes small, so that the electromotive force generated becomes small. Further, since the length of each side is reduced, the portion affected by the electromagnetic wave is reduced, so that the sensitivity to the electromagnetic wave can be reduced. Also, the radiation of noise can be reduced by the same effect.

Therefore, in the present embodiment, in FIG. 2, the width W1 of the piezoelectric vibrator 1 is 14.1 mm and the thickness T1 thereof is 0.37 m.
The distance W2 between the first electrode 2 and the second electrode 3 is 0.1 mm.
The first signal line 7 and the second signal line 8 are connected to a connector pin (not shown) for connecting the first signal line 7 and the second signal line 8 to a coaxial cable (not shown). Are closest to each other, and this is the closest contact 9. The distance T2 from the front end of the first signal line 7 and the second signal line 8 to the point where the first signal line 7 and the second signal line 8 are closest to each other from the lead-out portion of the second electrode 3 is 25.3 mm. The signal line loop area of the ultrasonic probe having such a structure is about 7.8 mm ² . At this time, when the electromagnetic wave immunity of the ultrasonic wave emitting surface of the ultrasonic probe was measured using the measuring method shown in FIG. 3,
As shown in B of FIG. 5, the worst value was −71 dB.

From these results, the results of comparison between the conventional example shown in FIG. 7 and the first embodiment of the present invention shown in FIG. 1 can be summarized as follows. In the conventional example, the first signal line
The 107 and the second signal line 108 were taken out from the opposite directions of the piezoelectric vibrator 102, and were routed so as to surround the back load material 109. Therefore, the closest contact 110 where the first signal line 107 and the second signal line 108 are closest to each other, the first signal line 107, and the first signal line
First electrode 103 of piezoelectric vibrator 102 electrically connected to 107
Also, the minimum area of the region surrounded by the second electrode 104 and the second signal line 108 electrically connected to the second electrode 104 is about 350 mm ² , and the electromagnetic wave immunity is the worst value of −52 dB at 1 MHz to 20 MHz. Met. Therefore, it is affected by noise generated by electromagnetic waves in the 1 to 20 MHz band. On the contrary,
In the first embodiment of the present invention, the first signal line 7 and the second signal line 8 electrically connected to the first electrode 2 and the second electrode 3 of the piezoelectric vibrator 1 are the same as those of the piezoelectric vibrator 1. By taking out from the direction, the closest contact 9 where the first signal line 7 and the second signal line 8 are closest to each other, the first signal line 7, and the piezoelectric vibrator 1 electrically connected to the first signal line 7. First electrode 2 and second electrode 3
Then, the area of the region surrounded by the second signal line 8 electrically connected to the second electrode 3 was reduced to about 7.8 mm ² . For this reason, the electromagnetic sensitivity is about the same as the conventional structure.
It is improved by 20 dB, and it is possible to prevent the influence of noise generation due to electromagnetic waves in the 1 to 20 MHz band.

As described above, according to the first embodiment of the present invention, the first signal line 7 and the second signal line 8 are drawn out from the side surface on the same side of the piezoelectric vibrator 1 in the vertical direction of the back surface. ,
Moreover, since the closest contact 9 is formed at a position within a distance of twice the width of the piezoelectric vibrator 1 from the front end of the first signal line 7, it is possible to reduce the area of the signal line loop and improve the electromagnetic wave resistance. It was

FIG. 6 is a partial schematic cross-sectional view of an ultrasonic probe according to the second embodiment of the present invention. As shown in this figure, in the second embodiment of the present invention, the first signal line drawn from the first electrode on the subject side of the piezoelectric vibrator is taken out from both sides of the piezoelectric vibrator, thereby Signal line and first
The electrical resistance between the electrodes was reduced, and the electromotive force generated when a current caused by electromagnetic waves flowed was reduced.

In this figure, the piezoelectric vibrator 11 and the first electrode
12, the second electrode 13, the back load material 14, the second acoustic matching layer 16, and the second signal line 18 are the same as the components having the same names in the first embodiment.

The first signal line 17 is electrically connected to both ends of the first electrode 12 on the subject side of the piezoelectric vibrator 11, and the back load member 14 is connected to the first signal line 17.
Are drawn out along the two side surfaces facing each other. The first signal line 17 individually pulled out from both sides is the back load member 14
Is electrically connected on the back side of. First acoustic matching layer 15
In order to take out the first signal line 17 from both sides of the first electrode 12, the first electrode 12 and the first signal line 17 are bonded to the subject side of the piezoelectric vibrator 11 leaving an electrically connected portion. There is.

The area of the signal line loop of the ultrasonic probe configured as described above is the same as that of the first embodiment, but the first signal line 17 functioning as the ground is connected to the piezoelectric vibrator.
By taking out from both sides of 11, the electric resistance between the first signal line 17 and the first electrode 12 becomes small, so that the electromotive force generated when a current due to an electromagnetic wave flows becomes small and the image information is The noise component mixed in becomes small. Further, since the signal line loop area is the same as that of the first embodiment,
Using the measuring method described in FIG. 3, when measuring the immunity force of the ultrasonic probe itself, as shown in C in FIG. 5, as in the first embodiment, be -71dB at worst value It can be seen that, compared with the conventional example, it is improved by about 20 dB.

As described above, according to the second embodiment of the present invention, by taking out the first signal line 17 from both sides of the piezoelectric vibrator 11, the signal line loop area becomes small, and the first signal line 17 becomes smaller.
The electrical resistance between the signal line 17 and the first electrode 12 can be reduced. Therefore, generation of electromotive force due to electromagnetic waves can be reduced, and electromagnetic wave resistance is improved.

In the first and second embodiments,
Although the array scanning type ultrasonic probe has been described, the same effect can be obtained for a mechanical sector type ultrasonic probe such as a single transducer. In addition, in FIG. 1 and FIG. 6, the signal line is from the end in the minor axis direction which is a direction perpendicular to the direction in which the piezoelectric vibrators 11 are arranged,
Although the signal line and the second signal line are drawn out, they may be drawn out from the major axis direction which is the same direction as the direction in which the piezoelectric vibrators are arranged. Further, the present invention is not limited by the configuration of the electrodes of the piezoelectric vibrator and the method of extracting the signal line from the electrodes of the piezoelectric vibrator. In addition, the first signal line or the second signal line may be electrically connected in common to the other first signal line and second signal line of the arrayed piezoelectric vibrators, respectively. The loop area is a point where the first signal line and the second signal line are closest to each other, the first signal line, the first electrode of the piezoelectric vibrator electrically connected to the first signal line, and
It is the area of the minimum region surrounded by the second electrode and the second signal line electrically connected to the second electrode.

[0034]

As described above, according to the present invention, the piezoelectric vibrator, the first electrode provided on the front surface of the piezoelectric vibrator, and the second electrode provided on the back surface of the piezoelectric vibrator. the first electrode and is electrically connected, and comprises a first signal line which is pulled out to the outside, the second electrode and being electrically connected, and a second signal line which is pulled out to the outside, the First belief
The signal line functions as a ground, and both of the piezoelectric vibrators are connected.
Withdrawn from the side, the first signal line and the second signal line and the coaxial cable on the rear side of the back load member, at least any one the electrical connector pins for connection to the printed wiring board or the coaxial cable Electrically connected, and the distance between the first signal line and the second signal line is the closest contact point at the location where the connection is made, and the closest contact point, the first signal line, the first electrode, and the first electrode The area of the signal line loop formed by two electrodes and the second signal line is 1/1000 mm
^{Since it is set to 2} or more and 160 mm ² or less, the first signal line and the first electrode
The electrical resistance between them was reduced, and a current flowed by electromagnetic waves
It is possible to reduce the electromotive force generated in some cases.
In addition, it is possible to provide an ultrasonic probe having an excellent effect of improving the electromagnetic wave immunity and particularly preventing the influence of noise due to electromagnetic waves in the 1 to 20 MHz band.

[0035]

[Brief description of drawings]

FIG. 1 is a partial schematic cross-sectional view of an ultrasonic probe according to a first embodiment of the present invention,

FIG. 2 is an explanatory diagram of a signal line loop area according to the first embodiment of the present invention,

FIG. 3 is an explanatory view of a method for measuring the electromagnetic resistance of the ultrasonic probe alone,

FIG. 4 is a characteristic diagram showing the relationship between the signal line loop area and the electromagnetic wave immunity of the ultrasonic probe,

FIG. 5 is a diagram showing measurement results of electromagnetic wave immunity,

FIG. 6 is a partial schematic cross-sectional view of an ultrasonic probe according to a second embodiment of the present invention,

FIG. 7 is a partial schematic cross-sectional view of a conventional ultrasonic probe,

FIG. 8 is an explanatory diagram of a signal line loop area of a conventional ultrasonic probe.

[Explanation of symbols]

1, 11 Piezoelectric vibrator 2, 12 1st electrode 3,13 Second electrode 4, 14 Back load material 5,15 1st acoustic matching layer 6, 16 2nd acoustic matching layer 7,17 1st signal line 8, 18 2nd signal line 9, 19 Recent contacts

Continuation of the front page (56) Reference JP-A-10-262968 (JP, A) JP-A-4-347146 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) H04R 17 / 00 330 A61B 8/00 G01N 29/24

Claims (3)

(57) [Claims] 1. A piezoelectric vibrator, a first electrode provided on a front surface of the piezoelectric vibrator, a second electrode provided on a back surface of the piezoelectric vibrator, and electrically connected to the first electrode. And a first signal line extended to the outside and a second signal line electrically connected to the second electrode and extended to the outside, the first signal line functioning as a ground, and
At least one of the connector pins that are taken out from both sides of the piezoelectric vibrator, and that the first signal line and the second signal line are connected to the coaxial cable, the printed wiring board, or the coaxial cable on the back side of the back load material. Electrically connected to one of the other, and the distance between the first signal line and the second signal line is the closest contact point at the place where the connection is made,
The area of a signal line loop formed by the closest contact point, the first signal line, the first electrode, the second electrode, and the second signal line is set to 1/1000 mm ² or more and 160 mm ² or less. An ultrasonic probe characterized by. Wherein said second signal line and the first signal line, before
Serial ultrasonic probe according to claim 1, wherein the closest to each other at a position within a distance of 2 times the width of the piezoelectric vibrator from the front end of the first electrode. Wherein the second signal line and the first signal line, before
The ultrasonic probe according to claim 1, wherein the ultrasonic probe is drawn out from the end of the piezoelectric vibrator in the minor axis direction.