KR20230077023A - Impedance matching layer - Google Patents

Abstract

In detail, one embodiment of the present invention provides an impedance matching layer that can be manufactured to match a required impedance. Here, the impedance matching layer is formed in a three-dimensional shape and includes a unit structure cell having a column portion formed in a region corresponding to a side and a space portion formed in an inner region surrounded by the column portion, and the unit structure cell includes a plurality of units. provided, and continuously disposed along a first direction through which acoustic waves are transmitted and a second direction crossing the first direction.

Description

Impedance Matching Layer {IMPEDANCE MATCHING LAYER}

The present invention relates to an impedance matching layer, and more particularly, to an impedance matching layer that can be manufactured to match a required impedance.

An acoustic wave device, for example, an ultrasound examination device, irradiates ultrasonic waves to a subject such as a person, animal, or object, detects an echo signal reflected in the subject, and displays a tomographic image of a tissue in the subject on a monitor. , provides information necessary for the examination of the subject.

Ultrasonic testing can be roughly divided into contact ultrasonic testing and non-contact ultrasonic testing, and contact ultrasonic testing transmits and receives ultrasonic waves using water or a couplant as a medium. In addition, the non-contact ultrasonic test transmits and receives ultrasonic waves through air (atmosphere) instead of water or a contact medium. Ultrasonic inspection is widely used in various fields such as medical and non-destructive detection.

On the other hand, whether the contact medium is water or air, it is important to match the impedance with the contact medium in order to ensure that the generated ultrasonic waves are well transmitted to the contact medium. Accordingly, the conventional ultrasonic device has an impedance matching layer. It is being used.

However, there is no commercial material having stiffness that satisfies the theoretical design value of the impedance matching layer. Therefore, in the prior art, an impedance matching layer was prepared by appropriately mixing a plurality of materials, but this method has problems in that it is difficult to implement homogeneous physical properties and productivity is low.

Republic of Korea Patent Publication No. 2017-0139698 (published on December 19, 2017)

In order to solve the above problems, a technical problem to be achieved by the present invention is to provide an impedance matching layer that can be manufactured to match a required impedance.

The technical problem to be achieved by the present invention is not limited to the above-mentioned technical problem, and other technical problems not mentioned can be clearly understood by those skilled in the art from the description below. There will be.

In order to achieve the above technical problem, an embodiment of the present invention is a unit structure cell formed in a three-dimensional shape and having a column portion formed in a region corresponding to a side and a space portion formed in an inner region surrounded by the column portion. Provides an impedance matching layer characterized in that a plurality of unit structure cells are provided, and continuously disposed along a first direction through which acoustic waves are transmitted and a second direction crossing the first direction. .

In an embodiment of the present invention, the unit structure cell may be formed in a rectangular parallelepiped shape.

In an embodiment of the present invention, the impedance matching layer may have a first contact surface in contact with a vibrating body generating acoustic waves, and the first contact surface may be formed in a form of a filled surface without forming an empty space.

In an embodiment of the present invention, the second contact surface of the impedance matching layer formed on the opposite side of the first contact surface and contacting the external medium may be formed in the form of a filled surface without forming an empty space.

In an embodiment of the present invention, among the plurality of unit structural cells, the cross-sectional area of the pillar portion of the unit structural cell disposed close to the vibrating body generating the acoustic wave is greater than the cross-sectional area of the column portion of the unit structural cell disposed far from the vibrating body. can be wide

In an embodiment of the present invention, among the plurality of unit structural cells, the size of unit structural cells disposed close to the vibrating body generating acoustic waves may be smaller than the size of unit structural cells disposed far from the vibrating body.

In an embodiment of the present invention, the unit structure cell may further have an auxiliary pillar portion disposed while connecting two spaced apart corners and crossing the space portion.

According to an embodiment of the present invention, the impedance matching layer is the form of the impedance matching layer capable of implementing the required impedance, for example, the length and thickness of the column part of the unit structure cell, the volume of the space part, the number of arranged unit structure cells As long as the back is calculated through theoretical calculation, it can be easily manufactured through 3D printing technology. Through this, an impedance matching layer capable of satisfying various required impedance conditions can be obtained in a customized manner.

The effects of the present invention are not limited to the above effects, and should be understood to include all effects that can be inferred from the detailed description of the present invention or the configuration of the invention described in the claims.

1 is a cross-sectional view illustrating an example in which an impedance matching layer according to an embodiment of the present invention is installed in an ultrasonic sensor.
2 is an exemplary view showing a part of an impedance matching layer according to an embodiment of the present invention.
FIG. 3 is a front view illustrating the impedance matching layer of FIG. 2 .
FIG. 4 is an image showing tensile and compressive load characteristics of the impedance matching layer of FIG. 2 .
5 is an exemplary view for explaining a first contact surface and a second contact surface of an impedance matching layer according to an embodiment of the present invention.
6 is an exemplary diagram for explaining an example of arrangement of unit structure cells in an impedance matching layer according to an embodiment of the present invention.
7 is an exemplary diagram for explaining another arrangement example of unit structure cells in an impedance matching layer according to an embodiment of the present invention.
8 is an exemplary diagram illustrating another example of an impedance matching layer according to an embodiment of the present invention.
9 is a front view illustrating the impedance matching layer of FIG. 8 .

Hereinafter, the present invention will be described with reference to the accompanying drawings. However, the present invention may be embodied in many different forms and, therefore, is not limited to the embodiments described herein. And in order to clearly explain the present invention in the drawings, parts irrelevant to the description are omitted, and similar reference numerals are attached to similar parts throughout the specification.

Throughout the specification, when a part is said to be "connected (connected, contacted, combined)" with another part, this is not only "directly connected", but also "indirectly connected" with another member in between. "Including cases where In addition, when a part "includes" a certain component, it means that it may further include other components without excluding other components unless otherwise stated.

Terms used in this specification are only used to describe specific embodiments, and are not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly dictates otherwise. In this specification, terms such as "include" or "have" are intended to indicate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, but one or more other features It should be understood that the presence or addition of numbers, steps, operations, components, parts, or combinations thereof is not precluded.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is an exemplary cross-sectional view showing an example in which an impedance matching layer according to an embodiment of the present invention is installed in an ultrasonic sensor, and FIG. 2 is an exemplary view showing a part of an impedance matching layer according to an embodiment of the present invention. 3 is a front view showing the impedance matching layer of FIG. 2 .

As shown in FIGS. 1 to 3 , the impedance matching layer 100 may be provided on the front surface of the vibrating body 11 and may emit ultrasonic waves generated by the vibrating body 11 .

The ultrasonic sensor of FIG. 1 may have a case 10 and a vibrating body 11 and an absorption unit 12 disposed inside the case 10 . Also, the vibrating body 11 may be a piezoelectric element, and the absorber 12 may be provided on a rear surface of the vibrating body 11 . The absorber 12 may act as a damper to limit vibration at the rear of the vibrator 11 by absorbing ultrasonic waves generated by the vibrator 11 . In FIG. 1 , the ultrasonic sensor is shown as having a case 10 and a vibrating body 11 and an absorption unit 12 disposed inside the case 10, but is not necessarily limited to this shape.

The impedance matching layer 100 may be disposed on the front surface of the vibrating body 11 , improve an impedance difference between the vibrating body 11 and an external medium, and increase the permeability of ultrasonic waves.

The impedance matching layer 100 may include a plurality of unit structure cells 110 . The unit structure cell 110 may be formed in a three-dimensional shape, preferably in a rectangular parallelepiped shape, and more preferably in a regular hexahedron shape.

Also, the plurality of unit structure cells 110 may be continuously arranged. Specifically, the unit structure cells 110 may be continuously arranged along the first direction A1 through which acoustic waves are transmitted. Also, the unit structure cells 110 may be continuously arranged along the second direction A2 crossing the first direction A1. The second direction A2 includes a 2-1st direction A2-1 and a 2-2nd direction A2-2 perpendicular to each other so that the rectangular parallelepiped unit structure cells 110 can be continuously arranged. can do. The first direction (A1), the 2-1 direction (A2-1), and the 2-2 direction (A2-2) may be perpendicular to each other, and through this, the plurality of unit structure cells 110 are formed in a three-dimensional can be arranged consecutively. The length of one side of the unit structure cell 110 may be as small as several to hundreds of μm. Through this, even though the unit structure cell 110 is formed in a rectangular parallelepiped shape, the impedance matching layer 100 can be formed in various shapes such as a cylinder shape. can

And, in this embodiment, the unit structure cell 110 may have a pillar portion 111 and a space portion 112 .

The pillar portion 111 may be formed in a region corresponding to the side of the unit structure cell 110 . Further, the space portion 112 may be formed in an inner region surrounded by the pillar portion 111 . The unit structure cell 110 according to this embodiment may have a three-dimensional truss-lattice structure.

The impedance matching layer 100 may be manufactured using 3D printing technology, and through this, the impedance matching layer 100 may be easily manufactured in various 3D structures.

As described above, since there is no commercial material that satisfies the mechanical characteristic impedance required for the front weight, it is difficult to manufacture an impedance matching layer capable of matching such characteristic impedance. However, the impedance matching layer 100 according to the present invention has a shape of the impedance matching layer 100 capable of implementing the required impedance, for example, the length and thickness of the pillar portion 111 of the unit structure cell 110, As long as the volume of the space portion 112, the number of arranged unit structural cells 110, etc. are calculated through theoretical calculation, it can be easily manufactured through 3D printing technology. Through this, an impedance matching layer capable of satisfying various required impedance conditions can be obtained in a customized manner.

FIG. 4 is an image showing tensile and compressive load characteristics of the impedance matching layer of FIG. 2 .

As shown in FIG. 4 , it can be seen that the unit structure cell 110 according to the present embodiment has a very high modulus of elasticity in the axial direction and high stiffness against tensile and compressive loads. Therefore, the impedance matching layer 100 having such a unit structure cell 110 can be effectively implemented in an environment where the influence of bending vibration of the front weight is small and the axial tensile and compressive loads are high.

5 is an exemplary view for explaining a first contact surface and a second contact surface of an impedance matching layer according to an embodiment of the present invention.

As shown in FIG. 5 together with FIG. 1 , the impedance matching layer 100 may have a first contact surface 101 in contact with the vibrating body 11 generating acoustic waves. Based on the traveling direction of sound generated from the vibrating body 11 , the first contact surface 101 may be the rear surface of the impedance matching layer 100 .

The first contact surface 101 is preferably formed in the form of a filled surface without forming an empty space. Through this, not only is there an effect of preventing compression deformation of the first contact surface 101, but also the impedance matching layer 100 and the vibrating body 11 can be more closely contacted, so that ultrasonic permeability can be improved.

The first contact surface 101 is formed at the same height while connecting the pillars at the rear end of the plurality of unit structure cells disposed in the portion in contact with the vibrating body 11 in the impedance matching layer 100 ((FIG. 5) (see a)), or may be formed to protrude more rearward than the pillar part at the rear end of the plurality of unit structure cells to have a thickness (see (b) of FIG. 5).

Also, the impedance matching layer 100 may have a second contact surface 102 formed on the opposite side of the first contact surface 101 and contacting an external medium. The second contact surface 102 may be the front surface of the impedance matching layer 100 based on the traveling direction of the sound generated by the vibrating body 11 .

The second contact surface 102 is preferably formed in the form of a filled surface in which no empty space is formed, through which radiated acoustic waves are effectively transmitted to an external medium and wear of the impedance matching layer 100 is effectively prevented. It can be.

When the external medium is a liquid such as water, watertightness can be improved by the second contact surface 102, and foreign substances included in the external medium can be prevented from flowing into the impedance matching layer 100.

The second contact surface 102 is formed at the same height while connecting the front end side pillars of a plurality of unit structure cells disposed on the front surface of the impedance matching layer 100 (see (a) in FIG. 5), or a plurality of unit structure cells. It may be formed so as to protrude forward more than the pillar portion at the front end of the two unit structural cells to have a thickness (see (b) in FIG. 5).

Meanwhile, among the plurality of unit structural cells, the cross-sectional area of the column of the unit structural cells disposed close to the vibrating body generating acoustic waves may be wider than the cross-sectional area of the unit structural cells disposed far from the vibrating body.

And, among the plurality of unit structural cells, the size of unit structural cells disposed close to the vibrating body generating acoustic waves may be smaller than the size of the unit structural cells disposed far from the vibrating body.

Accordingly, the density of a portion of the impedance matching layer disposed closer to the vibrator 11 may be higher, and through this, it may have impedance characteristics that change linearly in the thickness direction of the impedance matching layer.

6 is an exemplary diagram for explaining an example of arrangement of unit structure cells in an impedance matching layer according to an embodiment of the present invention.

As shown in FIG. 6, the unit structure cell 110-1 of the impedance matching layer region 100-1 disposed closest to the vibrating body 11 based on the vibrating body 11 in the impedance matching layer 100 The size of is the largest, and the size of the unit structure cell 110-2 of the next closest impedance matching layer region 100-2 is the next largest, and the impedance matching layer region 100-3 is the farthest away. The size of the unit structure cell 110-3 of ) may be the smallest.

Alternatively, FIG. 7 is an exemplary diagram for explaining another arrangement example of unit structure cells in an impedance matching layer according to an embodiment of the present invention. As shown in FIG. 7, the vibration body 11 in the impedance matching layer 100 ) may have the widest cross-sectional area of the pillar portion 111-1 of the unit structure cell 110-1 of the impedance matching layer region 100-1 disposed closest to . That is, the pillar portion 111-1 may be the thickest. And, the cross-sectional area of the pillar portion 111-2 of the unit structure cell 110-2 of the impedance matching layer region 100-2 disposed farther from the vibrating body 11 than the impedance matching layer region 100-1 is A unit structure cell of the impedance matching layer region 100-3, which may be thinner and narrower than the cross-sectional area of the pillar portion 111-1, and disposed farther from the vibrating body 11 than the impedance matching layer region 100-2 The cross-sectional area of the pillar portion 111-3 of (110-3) may be narrower and thinner than the cross-sectional area of the pillar portion 111-2.

In addition, the thickness of each impedance matching layer region 100 - 1 , 100 - 2 , and 100 - 3 may vary according to the operating wavelength of ultrasonic waves generated from the vibrating body 11 .

8 is an exemplary diagram illustrating another example of an impedance matching layer according to an embodiment of the present invention, and FIG. 9 is a front view illustrating the impedance matching layer of FIG. 8 . In this embodiment, the configuration of the unit structure cell may be different from the unit structure cell described in FIGS. 2 to 4, and other configurations are the same, so repetition is omitted as much as possible.

As shown in FIGS. 8 and 9 , the unit structure cell 110a of the impedance matching layer 100a according to the present embodiment may further include an auxiliary pillar portion 115 . That is, the unit structure cell 110a according to the present embodiment may have a three-dimensional truss-lattice structure having the auxiliary pillar portion 115 in the space portion 112 .

The auxiliary pillar portion 115 may be disposed while connecting two spaced apart corners and crossing the space portion 112 . Since the unit structure cell 110a can be reinforced in the diagonal direction by the auxiliary pillar part 115, the impedance matching layer 100a having the auxiliary pillar part 115 has stiffness against shear force and bending load. can

The above description of the present invention is for illustrative purposes, and those skilled in the art can understand that it can be easily modified into other specific forms without changing the technical spirit or essential features of the present invention. will be. Therefore, the embodiments described above should be understood as illustrative in all respects and not limiting. For example, each component described as a single type may be implemented in a distributed manner, and similarly, components described as distributed may be implemented in a combined form.

The scope of the present invention is indicated by the following claims, and all changes or modifications derived from the meaning and scope of the claims and equivalent concepts should be interpreted as being included in the scope of the present invention.

11: vibrating body
100, 100a, 100b: impedance matching layer
101: first contact surface
102: second contact surface
110, 110a, 110b: unit structure cell
111: column part
112: space part
115: auxiliary pillar part

Claims (7)

A unit structure cell formed in a three-dimensional shape and having a pillar part formed in an area corresponding to a side and a space part formed in an inner area surrounded by the pillar part;
The unit structure cell is provided in plurality, and is continuously disposed along a first direction through which acoustic waves are transmitted and a second direction crossing the first direction. According to claim 1,
The unit structure cell is an impedance matching layer, characterized in that formed in a rectangular parallelepiped shape. According to claim 1,
The impedance matching layer has a first contact surface in contact with a vibrating body generating acoustic waves,
The impedance matching layer, characterized in that the first contact surface is formed in the form of a filled surface without forming an empty space. According to claim 3,
The impedance matching layer, characterized in that the second contact surface of the impedance matching layer formed on the opposite side of the first contact surface and contacting the external medium is formed in the form of a filled surface without forming an empty space. According to claim 1,
Among the plurality of unit structural cells, the cross-sectional area of the pillar portion of the unit structural cell disposed close to the vibrating body generating the acoustic wave is larger than the cross-sectional area of the column portion of the unit structural cell disposed far from the vibrating body impedance matching layer. . According to claim 1,
Among the plurality of unit structural cells, the size of unit structural cells disposed close to the vibrating body generating acoustic waves is smaller than the size of unit structural cells disposed far from the vibrating body. According to claim 1,
The unit structure cell further comprises an auxiliary pillar portion connecting two spaced apart corners and crossing the space portion, characterized in that the impedance matching layer.

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