JP7461246B2 - Ultrasonic probe and its manufacturing method - Google Patents

Description

The present invention relates to an ultrasonic probe that includes a linear array probe as a first probe group and a second probe group arranged in the vicinity of the linear array probe, and has a structure that is easy to manufacture, and a method for manufacturing the same.

Ultrasonic probes are needed in various fields, and especially in the medical field, they are essential for diagnosing internal diseases of the human body. It is preferable if information such as the moving speed and amount of movement of the ultrasonic probe can be displayed on the display screen of the ultrasonic diagnostic apparatus, since this improves the ease of use of the ultrasonic probe.
For example, Patent Document 1 describes a first ultrasonic transducer array and a first ultrasonic transducer array disposed inside a contact surface that contacts a living body with a space therebetween, which transmits and receives ultrasonic waves obliquely to and from the contact surface. An ultrasonic diagnostic apparatus is disclosed that includes two or more second ultrasonic transducers, a transmitting/receiving means, a tomographic image generating means, a display means, a Doppler shift detecting means, and a movement calculating means. ).

According to the ultrasonic diagnostic apparatus disclosed in Patent Document 1, the relative movement speed or amount of movement of the ultrasonic probe with respect to the living body is determined using the transmission and reception signals of the second transducer (see Patent Document 1). range). Moreover, since the first ultrasonic transducer array and the second transducer are integrated, they are less susceptible to the effects of movement of the object to be diagnosed, so the above-mentioned movement speed and amount can be accurately determined. (for example, paragraph 8).
Furthermore, if second ultrasonic transducers are provided at multiple positions, it is possible to detect relative movement in each pair, and it is possible to detect not only parallel movement but also rotational movement of the ultrasonic probe (Paragraph 10). .

Patent No. 4090576

However, in the ultrasonic diagnostic device disclosed in Patent Document 1, the second ultrasonic transducer is disposed inside the ultrasonic probe with a gap between it and the contact surface that contacts the living body. Moreover, the second ultrasonic transducer is disposed so as to transmit and receive ultrasonic waves obliquely to the contact surface.
Therefore, there is a problem in that it is difficult to fabricate an ultrasonic probe portion including the first ultrasonic transducer array and the second transducer.
The present invention has been made in consideration of the above-mentioned points, and therefore, an object of the present application is to provide an ultrasonic probe comprising a linear array probe and a second probe group arranged in the vicinity of the linear array probe, which has a simple structure and is easy to manufacture, and a method for manufacturing the same.

In order to achieve this object, a first invention of this application is an ultrasonic probe including a linear array probe as a first probe group, at least one second probe group consisting of two or more probes arranged apart from each other, and an acoustic lens for adjusting the focus of the first probe group and the second probe group,
The ultrasonic probe has a transmitting/receiving surface of each of the probes constituting the first probe group and a transmitting/receiving surface of each of the probes constituting the second probe group that are flush with each other.
In carrying out this ultrasonic probe invention, it is preferable that the acoustic lens has, on a first surface side facing the first probe group and the second probe group, a first focus adjustment unit that adjusts the focus of each probe of the first probe group, and a second focus adjustment unit that adjusts the focus so that two or more probes of the second probe group have a common monitoring position.

The second invention of this application also provides a linear array probe as a first probe group, and at least one second set of probes including two or more probes arranged apart from each other. In manufacturing an ultrasonic probe comprising a probe group and an acoustic lens for focus adjustment of the first probe group and the second probe group,
preparing a structure having a first metal layer for forming a first electrode for an ultrasound probe, a piezoelectric layer, and a second metal layer for forming a second electrode in this order on a base;
a dividing step of dividing the structure into each probe of the first probe group and each probe of the second probe group;
a first focus adjustment section for adjusting the focus of each probe of the first probe group, on a first surface side facing the first probe group and the second probe group; preparing an acoustic lens having a second focus adjustment section that adjusts the focus so that two or more probes of the two probe groups have a common monitoring position;
The method for manufacturing an ultrasonic probe is characterized in that it includes a step of assembling the structure after the dividing step by assembling the first surface of the prepared acoustic lens so as to face the structure.

According to the ultrasound probe of this application, the transmitting and receiving surfaces of each probe constituting the first probe group and the transmitting and receiving surfaces of each probe constituting the second probe group are flush with each other, making it possible to realize an ultrasound probe with a simpler structure than conventional technology in which the second ultrasound transducer is spaced apart from the contact surface that comes into contact with the living body and is positioned so that ultrasound is transmitted and received at an angle to the contact surface.
According to a preferred embodiment of the ultrasound probe of this application, the focus adjustment of the ultrasound of each of the first and second probe groups is performed by a predetermined acoustic lens having a first focus adjustment unit and a second focus adjustment unit. Such an acoustic lens can be manufactured by cutting or molding, so even if such an acoustic lens is used, it is possible to realize an ultrasound probe with a simple structure compared to the conventional technology in which the probes are provided at intervals on the contact surface that contacts the living body and ultrasound is transmitted and received obliquely.

Further, according to the method for manufacturing an ultrasound probe of this application, a structure having a first metal layer, a piezoelectric layer, and a second metal layer for an ultrasound probe in this order is prepared on a base. , by dividing this structure into each probe of the first probe group and each probe of the second probe group, a first probe group and a second probe group are formed. Therefore, the main parts of the desired ultrasonic probe can be easily manufactured.

1A to 1C are diagrams illustrating an ultrasonic probe 10 according to a first embodiment. 2A to 2D are diagrams for explaining the ultrasonic probe 10 of the first embodiment, particularly the acoustic lens 30. FIG. FIG. 3 is a perspective view showing an example of an actual product of an ultrasound probe to which the present invention is applied. FIGS. 4A to 4D are diagrams illustrating ultrasound probes of other embodiments, and in particular, diagrams illustrating other examples of the arrangement of the second probe group. FIGS. 5A and 5B are main part process diagrams illustrating an embodiment of the invention of a manufacturing method.

Embodiments of each invention of this application will be described below with reference to the drawings. Note that the drawings used in the explanation are merely shown schematically to the extent that these inventions can be understood. Moreover, in each figure used for explanation, the same number is attached|subjected and shown about the same component, and the explanation may be abbreviate|omitted. Furthermore, the shapes, materials, etc. described in the following embodiments are merely preferred examples within the scope of the present invention. Therefore, the present invention is not limited only to the following embodiments.

1. First Embodiment of Ultrasonic Probe FIG. 1 is a diagram illustrating an ultrasonic probe 10 according to a first embodiment, and in particular, FIG. 1(A) shows a probe portion 20 and an acoustic lens 30. FIG. 1(B) is a perspective view showing the schematic structure of the probe portion 20, especially the main part 21 of the ultrasonic probe, and FIG. 1(C) is a perspective view showing the probe section 20 separately. FIG. 3 is a cross-sectional view of the probe portion 20 along line II in FIG.
Note that the probe portion 20 includes a main part 21 of the ultrasonic probe, a so-called backing layer 23, and an acoustic matching layer 25. However, the acoustic matching layer 25 may have a single layer or multiple layers such as two layers, depending on the design. This will be explained in detail below.

The main portion 21 of the ultrasonic probe includes a linear array probe 21a as a first probe group, and two second probe groups 21b and 21c.
For convenience of explanation, one of the two second probe groups is referred to as the first second probe group 21b, and the other is referred to as the second second probe group 21c. In addition, in Fig. 1 etc., the direction in which the probes 21aa of the linear array probe 21a are arranged, i.e., the long axis direction, is indicated as the X direction, and the direction perpendicular thereto, i.e., the short axis direction, is indicated as the Y direction.

The first probe group 21a has a large number of probes 21aa (see FIG. 1(B)) arranged linearly at a predetermined pitch P.
On the other hand, the first second probe group 21b is composed of two or more probes arranged apart from each other, here two probes 21ba and 21bb. The second set of second probe group 21c is composed of two or more probes arranged apart from each other, here two probes 21ca and 21cb.

The first set of second probe group 21b is provided at one end of both ends of the linear array probe 21a in the X direction, which is the long axis direction, and the two probes 21ba and 21bb are They are provided along the Y direction, separated by an interval ΔY.
The second probe group 21c of the second set is provided at the other end of both ends of the linear array probe 21a in the X direction, which is the long axis direction, and the two probes 21ca and 21cb are Along the Y direction, they are provided at intervals of ΔY.
Therefore, the four probes 21ba, 21bb, 21ca, and 21cb constituting the second probe group 21b and 21c are arranged in positions close to the four corners around the linear array probe 21a. has been done.
Note that the above-mentioned interval ΔY is preferably the same dimension as the dimension of the linear array 21a in the Y-axis direction. Although the details will be described later, this is because advantages such as ease of manufacturing the ultrasonic probe 10 can be obtained.

Further, the transmitting/receiving surface of each probe of the linear array probe 21a and the transmitting/receiving surface of each of the four probes 21ba, 21bb, 21ca, and 21cb of the second probe group are flush with each other. . That is, the transmitting/receiving surface of each probe of the linear array probe 21a and the transmitting/receiving surface of the four probes 21ba, 21bb, 21ca, and 21cb of the second probe group are flush with the XY plane. It is arranged so that.
In addition, each probe of the linear array probe 21a and each probe of the second probe group 21b, 21c are each a piezoelectric material 21d, as shown in FIG. 1(C). For example, it is made of PZT and electrodes 21e provided on the upper and lower surfaces of the piezoelectric body 21d.

Next, the acoustic lens 30 will be explained. This explanation will be given with reference to FIGS. 1 and 2. Here, FIG. 2(A) is a perspective view showing a state in which the probe portion 20 is mounted on the acoustic lens 30, and FIGS. 2(B) to (D) are respectively I 3 is a cross-sectional view of the acoustic lens 30 and the probe portion 20 along lines -I, II-II, and III-III. FIG.
The acoustic lens 30 of this embodiment, as shown in FIG. A recess 30a in which the probe portion 20 can be contained is provided on the side of the first surface 31 that faces the probe portion 20. A first focus adjustment section 33 and a second focus adjustment section 35 are provided using the first surface 31 side, more specifically, the bottom and side surfaces of the recess 30a. Each component will be specifically explained below.

2A, the probe portion 20 is assembled in the recess 30a of the acoustic lens 30, leaving a space, and this space is filled with adhesive 30b to connect the probe portion 20 and the acoustic lens 30. Note that an adhesive having a physical property of a sound speed slower than that of the constituent materials of the first focus adjustment unit 33 and the second focus adjustment unit 35 is used as the adhesive 30b.
The second surface 37 of the acoustic lens 30 opposite to the first surface 31 is a flat surface. The flat surface here not only means a flat surface, but also includes a substantially flat surface that does not have any unevenness that would be a problem when the ultrasonic probe 10 is brought into contact with a diagnostic surface of a human body or the like to be diagnosed with the ultrasonic probe 10.

The first focus adjustment section 33 adjusts the focus of each probe 21aa of the linear array 21a, which is the first probe group 21a. Specifically, the first focus adjustment unit 33 moves each probe 21aa along a region F (see FIG. 2A) on a substantially straight line along the X direction below the linear array probe 21a. It is intended to bring the focus of Therefore, in the case of this embodiment, the first focus adjustment section 33 is formed at the bottom of the acoustic lens 30, is long along the X direction, and has a circular shape near the center toward the second surface 37 in the Y direction. It is composed of a concave portion curved into an arc.

On the other hand, the second focus adjustment section 35 adjusts the focus so that two or more probes of the second probe group have a common monitoring position. Specifically, for the first second ultrasonic probe group 21b, the probe 21ba and the probe 21bb are located at a common monitoring position (F2 in FIGS. 2(A) and 2(C)). ), the focus of the two probes 21ba and 21bb is adjusted so that the probes 21ba and 21bb have the same angle. Regarding the second ultrasonic probe group 21c of the second set, the probe 21ca and the probe 21cb are arranged so that they have a common monitoring position (F3 in FIGS. 2(A) and 2(C)). , to adjust the focus of the two probes 21ca and 21cb. Hereinafter, the focus adjustment section for the second probe group 21b of the first set will be referred to as the focus adjustment section 35a, and the focus adjustment section for the second probe group 21c of the second set will be referred to as the focus adjustment section 35b. There is also.
In this embodiment, the two focus adjustment parts 35a and 35b are provided at both ends of the recessed part 30a of the acoustic lens 30 in the X direction, facing each other in the Y direction, and increasing toward the second surface 37 side. It is constituted by adjacent inclined portions 35c. That is, the above-mentioned inclined portion 35c is provided in a region corresponding to both ends of the two side walls along the X direction of the recessed portion 30a in the X direction.

The acoustic lens 30 is made of a material whose sound speed is faster than that of the human body, and is preferably made of a resin lens. When the acoustic lens 30 is made of a resin lens, an effect can be obtained in that the recess 30a, the first focus adjustment section 33, and the two second focus adjustment sections 35a and 35b can be formed relatively easily by molding or cutting. In addition, when the acoustic lens 30 is made of a silicon lens, the portion corresponding to the focus adjustment section for the second probe group becomes convex toward the surface to be diagnosed, and the surface to be diagnosed cannot be made flat. When the lens 30 is made of a resin lens, it is possible to obtain the effect that the surface to be diagnosed of the ultrasound probe 10 can be made flat. Any suitable resin may be used, but polymethylpentene is preferred, for example. This is described in Japanese Patent Application Laid-Open No. 2019-62496 filed by the applicant of the present application, so a description thereof will be omitted.

According to the ultrasound probe 10 of the present invention, the transmitting and receiving surfaces of the linear array probe 21a, which is the first probe group, and the second probe groups 21b and 21c are flush with each other, and the focal points of the probes of these probe groups can be fixed as specified by a specified acoustic lens 30. Therefore, according to the ultrasound probe 10 of the embodiment, the relative moving speed or amount of movement of the probe with respect to the living body can be obtained by the principle based on the Doppler shift described in Patent Document 1 (the principle described in paragraphs 16 to 22 of Patent Document 1). In addition, due to the fact that the transmitting and receiving surfaces of the linear array probe 21a and the second probe groups 21b and 21c are flush with each other, an ultrasound probe with a simple structure and easy manufacturing can be realized.

The ultrasonic probe 10 according to the present invention is actually used in a form as shown in FIG. 3, for example. That is, the ultrasonic probe 10 is mounted at a predetermined position on the flexible printed wiring board 40. A connector 40a is provided at another location on the flexible printed wiring board 40. The first electrode and the second electrode of each probe of the first probe group and the second probe group of the ultrasonic probe 10 are respectively connected to the wiring pattern 40b provided on the flexible printed wiring board 40. connected, and thus ultimately connected to connector 40b.
The flexible printed wiring board 40 on which the ultrasound probe 10 is mounted is bent into an appropriate shape and mounted in a housing 50 for the ultrasound probe.

2. Other embodiments of ultrasonic probe In the case of the ultrasonic probe 10 of the first embodiment described above, the second probe group is composed of two sets of second probe groups 21b and 21c, and the probes 21ba, 21bb, 21ca, and 21cb are provided at the four corners around the first probe group, but the number and arrangement of the second probe groups may be other. Below, some other examples will be described with reference to Figures 4(A) to (D). Note that Figures 4(A) to (D) are all examples of the arrangement of one set of second probe groups 21b, and are schematic diagrams focusing on one set of second probe groups 21b. However, Figures 4(A) to (C) also show views of the vicinity of the second probe group 21b viewed from above (surrounded by a broken line circle).

The example shown in FIG. 4A is an example in which one set of second probe groups 21b is provided only at one end of both ends of the linear array probe 21a in the X direction, which is the long axis direction.
In the example shown in FIG. 4(B), one set of second probe group 21b is provided near one of both ends of the linear array probe 21a in the X direction, which is the long axis direction. , is an example in which two probes constituting one second probe group 21b are arranged in a direction diagonal to the Y direction.
The example shown in FIG. 4(C) is an example in which one set of second probe group 21b is provided near one end of both ends of the linear array probe 21a in the X direction, which is the long axis direction. This is an example in which one second probe group 21b is composed of three probes, and the three probes are arranged at the vertices of a triangle when viewed in plan.
The example shown in FIG. 4(D) is an example in which a set of second probe groups 21b is provided at one end of both ends of the linear array probe 21a in the Y direction, which is the short axis direction. That is, this is an example in which two probes are arranged apart from each other by ΔX along the X-axis direction. In the example of FIG. 4(D), the dimension ΔX is the dimension in the X direction of the linear array probe 21a, which is the first probe group, but ΔX can be changed according to the design. Of course, the dimension in the X direction of the child 21a may be narrower than its younger brother.

Here, the second focus adjustment section corresponding to the arrangement example of the second probe group shown in FIGS. ) is processed so that an ultrasonic wave path is formed according to each arrangement example of the second probe group shown in FIGS. 4(A) to 4(D). This can be achieved by
In the above, the number of groups in the second probe group is 1 or 2, but the number of groups in the second probe group may be 3 or more if necessary. Further, the number of probes constituting the second probe group may also be four or more.
By variously changing the arrangement of each probe of the second probe group, including those illustrated in FIGS. 4(A) to 4(D), an ultrasonic probe using the second probe group It is expected that the efficiency and accuracy of the detection process of the movement speed and amount of movement will be improved.

3. Embodiment of Ultrasonic Probe Manufacturing Method Next, an embodiment of the manufacturing method according to the second aspect of the invention will be described with reference to FIG.
First, prepare a base 61. The base 61 may be any suitable one, such as a substrate for a backing layer, a base plate for dicing in consideration of a subsequent division step, or a flexible wiring board.
Also, a structure 69 is prepared, which has a first metal layer 63 for forming a first electrode for an ultrasonic probe, a piezoelectric layer 65, and a second metal layer 67 for forming a second electrode. This structure 69 is obtained by previously forming the first metal layer 63 and the second metal layer 67 of a predetermined shape on the upper and lower surfaces of a piezoelectric body 65. Specifically, the structure 69 is obtained by plating the piezoelectric body 65 for the first metal layer 63 and the second metal layer 67, or by printing and sintering a metal paste for the first metal layer 63 and the second metal layer 67 on the piezoelectric body 65, or by forming a metal film for the first metal layer 63 and the second metal layer 67 on the piezoelectric body 65 by a film forming method such as sputtering or vapor deposition.
Next, a structure 69 is placed on the base 61, and typically, the structure is bonded to the base 61 (FIG. 5(A)).

Next, a dividing step is performed to divide the structure 69 into each of the probes of the first probe group and each of the probes of the second probe group ( FIG. 5B ). This is typically performed by cutting along the Y direction, which is the short axis of the probes of the first probe group, with a dicing saw (not shown), repeatedly at a pitch P along the X direction. Note that the first metal layer 63 is a common electrode for the probes, and is therefore typically not divided. However, depending on the design, the first metal layer 63 may also be divided.
In this division process, the region of each probe of the second probe group, i.e., the region marked with 21ba in FIG. 5, for example, is also divided at the pitch P of the probes of the first probe group. However, this does not pose a problem because each cut and divided portion of the region of probe 21ba can be connected to each other later by wiring processing, or the ends of the portions to be cut can be connected in advance and then divided, so that these cut portions can be reconstructed as one probe of the second probe group.
Furthermore, when the region of each probe of the second probe group, i.e., for example, the region marked with 21ba in FIG. 5, is divided by the pitch P of the probes of the first probe group, the vibration mode of each probe of the second probe group can be made the same as the vibration mode of each probe of the first probe group, which has the effect of making the acoustic matching layer 30b etc. common to the first probe group and the second probe group.

Moreover, apart from each of the above steps, a predetermined acoustic lens 30 as described above is prepared. That is, an acoustic lens 30 having a recess 30a, a first focus adjustment section 33, and second focus adjustment sections 35a and 35b as shown in FIGS. 1 and 2 is prepared. This can be done, for example, by cutting solid resin or molding resin.

Then, the first surface of the prepared acoustic lens is opposed to the structure obtained in the above division step, and the two are assembled to obtain the ultrasonic probe 10. However, before this assembly step, various steps such as a step of processing the electrodes of the probe and a step of forming a matching layer are performed.
According to this manufacturing method of the present invention, the respective probes of the first probe group and the second probe group can be easily manufactured by the stacking process shown in FIG. 5(A) and the division process shown in FIG. 5(B), and a structure in which the surfaces of these probes are flush can be easily formed, thereby obtaining the effect of easily manufacturing an ultrasonic probe.

10: Ultrasonic probe of the first embodiment 20: Probe portion 21: Main portion of ultrasonic probe 21a: First probe group 21b: First set of second probe group 21c: Second set of second probe group 21d: Piezoelectric body 21e: Electrode 21aa, 21ba, 21bb, 21ca, 21cb: Probes (individual probes)
23: Backing layer 25: Acoustic matching layer 30: Acoustic lens 30a: Recess 30b: Adhesive 31: First surface of acoustic lens 33: First focus adjustment section 35, 35a, 35b: Second focus adjustment section 37: Second surface of acoustic lens 61: Base 63: First metal layer 65: Piezoelectric layer 67: Second metal layer 69: Structure

Claims (7)

a linear array probe as a first probe group; at least one second probe group consisting of two or more individual probes arranged apart from each other; and the first probe group. an acoustic lens having a first focus adjustment section that adjusts the focus of each probe of the group; and a second focus adjustment section that adjusts the focus so that the two or more individual probes have a common monitoring position. In an ultrasonic probe comprising,
The transmitting/receiving surface of each probe constituting the first probe group and the transmitting/receiving surface of each probe constituting the second probe group are flush with each other,
The acoustic lens has a concave portion containing the first probe group and the second probe group on a first surface side facing the first probe group and the second probe group. ,
In the area facing the first probe group on the bottom surface of the recess, there is a long strip along the direction in which each of the probes is lined up, and the vicinity of the center in the direction perpendicular to the lined up direction is different from the first surface. It has a concave portion curved in an arc shape on the second surface side, which is the opposite side, and
a region of the recess facing the second group of probes has an inclined surface descending from a side surface of the recess toward the second surface;
The concave portion curved in an arc shape constitutes the first focus adjustment portion, and the inclined surface constitutes the second focus adjustment portion.
An ultrasonic probe featuring: The second probe group is composed of two individual probes arranged at at least one of both ends of the direction in which each probe of the linear array is arranged along a direction perpendicular to the direction in which the probes are arranged. The ultrasonic probe according to claim 1 , characterized in that: The second probe group includes a total of four individual probes, two of which are arranged along a direction perpendicular to the direction in which the probes of the linear array are arranged, at each end of the direction in which the probes are arranged, and the two probes at one end of the both ends constitute the first set of second probe group, and the two probes at the other end of the both ends constitute the second probe group. The ultrasonic probe according to claim 1, wherein the ultrasonic probe constitutes a second probe group of the set. The individual probes of the second probe group are arranged on both sides of the linear array in the direction in which the probes of the linear array are lined up,
The inclined surface of the second focus adjustment section is provided in a region facing each of the probes disposed on both sides in the alignment direction, and approaches closer toward the second surface. The ultrasonic probe according to item 1 . Each probe of the second probe group is formed by connecting probes arranged at the same pitch as the arrangement pitch of each probe of the first probe group with wiring to form one probe. The ultrasonic probe according to any one of claims 1 to 4 , which is a reconstructed probe. The ultrasonic probe according to claim 1 , wherein the acoustic lens is a resin lens. a linear array probe as a first probe group; at least one second probe group consisting of two or more probes arranged apart from each other; and the first probe group. and an acoustic lens for focus adjustment of the second probe group, in manufacturing an ultrasound probe comprising:
preparing a structure having a first metal layer for forming a first electrode for an ultrasound probe, a piezoelectric layer, and a second metal layer for forming a second electrode in this order on a base;
a dividing step of dividing the structure into each probe of the first probe group and each probe of the second probe group;
a first focus adjustment section for adjusting the focus of each probe of the first probe group, on a first surface side facing the first probe group and the second probe group; preparing an acoustic lens having a second focus adjustment section that adjusts the focus so that two or more probes of the two probe groups have a common monitoring position;
A method for manufacturing an ultrasonic probe, comprising the step of assembling the structure after the dividing step with the first surface of the prepared acoustic lens facing each other.

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