JP4638854B2 - Manufacturing method of ultrasonic probe - Google Patents

Description

  The present invention relates to a method of manufacturing an ultrasonic probe used when performing extracorporeal scanning or intrabody scanning on a subject.

  In the medical field, various imaging techniques have been developed in order to observe and diagnose the inside of a subject. In particular, ultrasonic imaging that acquires internal information of a subject by transmitting and receiving ultrasonic waves enables real-time image observation, and other medical uses such as X-ray photographs and RI (radio isotope) scintillation cameras. Unlike imaging technology, there is no radiation exposure. Therefore, ultrasonic imaging is used as a highly safe imaging technique in a wide range of areas including gynecological system, circulatory system, digestive system, etc. in addition to fetal diagnosis in the obstetrics field.

  Ultrasound imaging is an image generation technique that utilizes the property that ultrasonic waves are reflected at boundaries between regions with different acoustic impedances (for example, boundaries between structures). Usually, an ultrasonic imaging device (also referred to as an ultrasonic diagnostic device or an ultrasonic observation device) is used by being inserted into a body cavity of an ultrasonic probe used in contact with the subject or the subject. An ultrasonic probe is provided. Alternatively, there may be provided an ultrasonic endoscope in which an endoscope that optically observes the inside of a subject and an ultrasonic probe for body cavity are combined. An ultrasonic beam is transmitted from such an ultrasonic probe or an ultrasonic endoscope (hereinafter referred to as an ultrasonic probe or the like) into a subject such as a human body, thereby performing an ultrasonic probe. Ultrasonic image information is acquired by receiving an ultrasonic echo generated in the subject using a child or the like. Based on this ultrasonic image information, the outline of the structure (for example, internal organs, lesion tissue, etc.) existing in the subject is extracted by obtaining the reflection point and reflection intensity at which the ultrasonic echo is generated.

In a general ultrasonic probe, as an ultrasonic transducer that transmits and receives ultrasonic waves, a vibrator (piezoelectric vibrator) in which electrodes are formed on two opposing surfaces of a piezoelectric body is used. Such an ultrasonic transducer (hereinafter, also simply referred to as an element) is used in a state where a backing layer is disposed on the back side and an acoustic matching layer and an acoustic lens are disposed on the ultrasonic transmission surface side.
The backing layer is made of a material with large acoustic attenuation, such as epoxy resin containing ferrite powder, metal powder, PZT powder, or rubber containing ferrite powder, and can quickly remove unwanted ultrasonic waves generated by the ultrasonic transducer. Provided to attenuate.

  The acoustic matching layer is formed of Pyrex (registered trademark) glass, an epoxy resin containing metal powder, or the like, and is provided for efficiently transmitting ultrasonic waves generated in the vibrator to the subject. Here, the acoustic impedance of a piezoelectric ceramic such as PZT (lead zirconate titanate) is about 34 MRayl, whereas the acoustic impedance of a living body as a subject is about 1.6 MRayl. For this reason, when they are brought into direct contact, the reflection at the boundary surface is too large, so that the ultrasonic waves generated in the vibrator can hardly be propagated into the subject. Therefore, by inserting a material (acoustic matching layer) having an acoustic impedance between the piezoelectric body and the object and gradually changing the acoustic impedance, the propagation efficiency of ultrasonic waves at the boundary between different media can be improved. It is improving. In general, the thickness of the acoustic matching layer is designed to be 1/4 of the wavelength of the ultrasonic wave propagating therethrough. The reason for this is that, as described in Non-Patent Document 1, when the thickness of the acoustic matching layer is designed in this way, the reflection wave and the direct wave in the acoustic matching layer are superposed on each other after the half wavelength of the direct wave This is because the waveform of the direct wave can be brought close to an ideal impulse waveform.

Furthermore, the acoustic lens is formed of, for example, a silicone resin, and converges the ultrasonic wave generated from the vibrator, thereby forming a focal point of the ultrasonic beam at a desired depth in the subject.
In the manufacturing process of a general ultrasonic probe, the acoustic matching layer and the acoustic lens are bonded to an ultrasonic transducer using an adhesive with a member molded to a desired thickness by polishing. It is formed. Alternatively, after the members of the acoustic matching layer and the acoustic lens are attached to the ultrasonic transducer, the members may be polished to a desired thickness.

  By the way, in the probe for body cavity, ultrasonic waves having a frequency of about 3.5 MHz to 7.5 MHz are usually used. However, in recent years, in order to obtain higher resolution, there has been an increasing demand for higher frequencies for ultrasonic probes. For example, in a body cavity probe such as the digestive tract, a frequency of about 25 MHz may be required.

However, when the ultrasonic probe is increased in frequency, the acoustic matching layer formed on the ultrasonic transducer must be thinned according to the wavelength of the ultrasonic wave. For example, when the sound velocity in the acoustic matching layer is 2500 m / s, the wavelength of the ultrasonic wave is about 2.5 × 10 ⁻⁴ m / s in an ultrasonic probe having a center frequency of 10 MHz. Therefore, the thickness of the acoustic matching layer is about 62.5 μm, which is a quarter of the wavelength. Further, in the ultrasonic probe having a center frequency of 25 MHz, since the wavelength of the ultrasonic wave is about 100 μm, the thickness of the acoustic matching layer is about 25.0 μm, which is ¼ of the wavelength. However, in the polishing process for the acoustic matching member and the bonding process for attaching the acoustic matching member to the ultrasonic transducer, the processing accuracy is at most about several μm. Further, when the adhesion accuracy is fixed (that is, when the thickness of the adhesive layer inserted between the piezoelectric layer and the acoustic matching layer is fixed), the thickness of the adhesive layer particularly in an element corresponding to a high frequency. This strongly affects the characteristics of the device. For example, in an element corresponding to 25 MHz, the thickness of the adhesive layer reaches 10% or more of the thickness of the acoustic matching layer. Such variation in thickness greatly changes the waveform of ultrasonic waves transmitted and received from the ultrasonic probe and the band performance. Therefore, in an ultrasonic transducer array in which a plurality of ultrasonic transducers are arranged, performance variation occurs between elements.

  In recent years, convex (convex) ultrasonic probes capable of obtaining a wide viewing angle have been widely used. Usually, such an ultrasonic probe has an element array in which a plurality of ultrasonic transducers are two-dimensionally arranged on a curved surface curved in one direction. Here, if the curved direction is the azimuth direction (scanning direction) and the direction orthogonal to the azimuth direction on the same plane is the elevation direction, the ultrasonic wave is converged to a predetermined depth in the convex element array. Therefore, an acoustic lens having a curvature in the elevation direction is formed. Therefore, in order to accurately form the focal point of the ultrasonic beam at a desired depth, the curvature of the acoustic lens must be formed exactly parallel to the elevation axis.

  Furthermore, when an adhesive is used, there is a possibility that peeling may occur at the joint portion between the vibrator and the acoustic matching layer or at the joint portion between the acoustic matching layer and the acoustic lens. In addition, since the adhesive is disposed, there is a problem that the transmittance of ultrasonic waves at the interface between adjacent layers is reduced, and the propagation efficiency of ultrasonic waves becomes non-uniform due to unevenness of the adhesive.

  As a related technique, Patent Document 1 discloses a step of manufacturing a piezoelectric layer, a step of covering the piezoelectric layer with a metal coating, a step of bonding the acoustic impedance matching layer to the metal coating, and an acoustic impedance matching layer. Placing the coated piezoelectric material in the mold with the layer disposed below the coated piezoelectric material layer and a mixture comprising epoxy resin, tungsten particles and silver particles on the top surface of the coated piezoelectric material layer. Injecting into the mold; degassing the mixture in the mold; curing the mixture in the mold until the mixture is dried and adhered to the coated piezoelectric material layer; A method of manufacturing a piezoelectric transducer comprising a removing step is disclosed.

  In Patent Document 1, a base material is formed by injecting a liquid resin onto a piezoelectric layer disposed in a mold and curing it. However, unlike the base material, a high accuracy is required for the thickness of the acoustic matching layer. Therefore, the method for forming the base material in Patent Document 1 cannot be directly applied to the formation of the acoustic matching layer.

  Further, in Patent Document 2, in a molding method for obtaining a molded article having a multilayer structure by sandwich molding of thermoplastic resin, (1) the injection speed when filling the mold cavity with the thermoplastic resin forming the core layer is disclosed. 300 mm / sec or more, and (2) when the glass transition temperature of the thermoplastic resin of the skin layer is Tg, the main mold temperature is maintained at a temperature lower than Tg, and the thermoplastic resin is the mold A molding method is disclosed in which the maximum temperature of the cavity surface and the core surface when in contact with the cavity direction and the core surface is (Tg + 1) ° C. to (Tg + 50) ° C.

Furthermore, Patent Document 3 discloses that one surface of a plate-like body is formed by attaching a piezoelectric film to one surface of the ultrasonically transparent plate-like body, such as plastic, which is in contact with the liquid to be measured and applying ultrasonic waves. An ultrasonic liquid level meter that detects and measures the liquid level by detecting echoes having different sizes depending on whether or not the liquid is in contact with the liquid is disclosed.
JP-T-2002-514874 (3rd page, FIG. 1) JP 2001-88165 A (first page) JP-A-9-101191 (first page) Masayasu Ito, Tsuyoshi Mochizuki “Ultrasound Diagnostic Device”, Corona, p. 30

  Accordingly, in view of the above points, the present invention provides an ultrasonic probe capable of forming an acoustic matching layer and an acoustic lens with high accuracy in an ultrasonic transducer that transmits and receives ultrasonic waves in the ultrasonic probe. It aims at providing the manufacturing method of.

  In order to solve the above-mentioned problem, an ultrasonic probe manufacturing method according to one aspect of the present invention includes at least one ultrasonic transducer that transmits and receives ultrasonic waves, and directly or on the at least one ultrasonic transducer. In a method of manufacturing an ultrasonic probe having an indirectly arranged member for propagating ultrasonic waves transmitted from at least one ultrasonic transducer, a mold in which the shape of the member is formed is prepared. Disposing at least one ultrasonic transducer therein (a) and transmitting ultrasonic waves from the at least one ultrasonic transducer and receiving the ultrasonic waves or reflected waves of the ultrasonic waves in the mold, Determining the relative position of the mold and the at least one ultrasonic transducer (b); and at least one Of the mold relative position has been determined with the ultrasonic transducer comprises a step (c) curing the member from the liquid state.

  According to the present invention, since the relative position of the ultrasonic transducer array with respect to the inner wall of the mold is determined based on the ultrasonic waves transmitted and received by the ultrasonic transducer array, the acoustic matching layer and the acoustic lens member are thin and accurate. It becomes possible to form. In addition, since the member such as the acoustic matching layer is directly disposed on the ultrasonic transducer array, it is possible to improve the propagation efficiency of ultrasonic waves. Furthermore, by using the molding method, an acoustic matching layer or the like can be easily formed at a low cost and with a high yield.

Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to the drawings. The same constituent elements are denoted by the same reference numerals, and the description thereof is omitted.
FIG. 1 is a flowchart showing a method for manufacturing an ultrasonic probe according to the first embodiment of the present invention.
First, in step S1 of FIG. 1, the ultrasonic transducer array 10 is disposed on the backing layer 11 as shown in FIG.

  The backing layer 11 is formed of a material having a large acoustic attenuation, such as an epoxy resin containing ferrite powder, metal powder, PZT powder, or rubber containing ferrite powder. As shown in FIG. 2, when a convex type (convex type) ultrasonic transducer array is manufactured, the element array surface of the backing layer 11 is formed into such a shape by a molding method or a polishing method. A plurality of ultrasonic transducers 12 are arranged on the backing layer 11 so as to have a desired arrangement. Further, in order to fix the positions of the plurality of ultrasonic transducers 12 and protect them, a filler 13 such as an epoxy resin is disposed between the adjacent ultrasonic transducers 12. Alternatively, a plurality of ultrasonic transducers 12 whose positions are fixed in advance by the filler 13 may be attached to the backing layer 11 using an adhesive.

  On the other hand, in step S2 of FIG. 1, a mold (mold 21 shown in FIG. 3) in which the shape of the acoustic matching layer disposed on the ultrasonic transducer array 10 is dug is prepared. As the mold material, it is preferable to use a material such as Teflon (registered trademark) that can easily peel off a resin material or glass that is a material of the acoustic matching layer (acoustic matching material). Further, in order to form a highly accurate acoustic matching layer, it is necessary to polish the inner wall of the mold to have a desired curved surface.

Next, in step S3 of FIG. 1, as shown in FIG. 3A, the acoustic matching material 22 is poured into the mold 21 in a liquid state, and the ultrasonic transducer manufactured in step S1 therein. The array 10 is arranged.
As the acoustic matching material 22, for example, an epoxy resin or a material obtained by mixing a powder of alumina, zirconia, tungsten, or the like into an epoxy resin is used. When using the latter, those prepared in advance by mixing these powders with a liquid resin material are prepared.

  Further, a measurement system circuit including a drive signal supply source (pulser) 23, an oscilloscope 24, and a switch 25 is connected to a predetermined number of ultrasonic transducers 12 included in the ultrasonic transducer array 10. The switch 25 switches between supply of a drive signal from the pulser 23 to the ultrasonic transducers used in alignment and input of the received signals output from the ultrasonic transducers to the oscilloscope 24. Here, in this alignment, it is preferable to use at least the ultrasonic transducers 12a and 12b located near the center and the end of the ultrasonic transducer array 10, and as the number of ultrasonic transducers 12 used increases. , Positioning accuracy is improved. In FIG. 3A, only the measurement system circuit connected to the ultrasonic transducer located at the end of the ultrasonic transducer array 10 is shown as a representative.

  Next, in step S4, the ultrasonic transducer array 10 is aligned so that the gap between the inner wall of the mold 21 and the surface of the ultrasonic transducer array 10 matches the thickness of the acoustic matching layer to be formed. The relative position between the mold 21 and the ultrasonic transducer array 10 is determined.

  The alignment is performed as follows. First, an ultrasonic wave is transmitted by supplying the drive signal generated in the pulser 23 to each of the ultrasonic transducers 12 a and 12 b, and an ultrasonic echo reflected from the inner wall of the mold 21 is received. As the drive signal, for example, a signal having a half width of about 50 nsec to 100 nsec and a voltage value of about −500 V to −100 V is used.

  FIG. 3B shows a waveform of a reception signal representing an ultrasonic echo received by the ultrasonic transducer 12a shown in FIG. FIG. 3C shows a waveform of a received signal representing an ultrasonic echo received by the ultrasonic transducer 12b shown in FIG. In FIGS. 3B and 3C, the horizontal axis indicates time, and the vertical axis indicates the voltage of the received signal.

  As shown in FIGS. 3B and 3C, the time intervals T and T between the generation timing of the drive signal and the detection timing of the reception signal output when each ultrasonic transducer receives the ultrasonic echo. 'Corresponds to the distance that the ultrasonic waves transmitted from the ultrasonic transducers 12a and 12b reciprocate between the inner wall of the mold 21 as shown in FIG.

Therefore, while monitoring the time intervals T and T ′ using the oscilloscope 24, the position of the ultrasonic transducer array 10 is adjusted so that the distance between the ultrasonic transducers 12a and 12b and the inner wall of the mold 21 becomes a desired length. Adjust. For example, when it is desired to form an acoustic matching layer with a thickness Th of 100 μm using an epoxy resin, if the speed of sound in a liquid epoxy resin is VL = 1000 m / s, the time intervals T and T ′ observed by the oscilloscope 24 are expressed by the following equations: (1) should be satisfied.
T = T ′ = Th × 2 / VL (1)
= (100 × 10 ⁻⁶ ) × 2/1000 sec
= 2.00 × 10 ⁻⁷ sec
= 0.2 μsec

  As shown in FIGS. 4B and 4C, when each time interval T and T ′ reaches a desired value (for example, T = T ′ = 0.2 μsec), in step S5 of FIG. (A), the liquid acoustic matching material 22 is cured while maintaining the distance between the surface of the ultrasonic transducer array 10 and the inner wall of the mold 21.

  Next, in step S <b> 6, the acoustic matching layer 14 is removed from the mold 21, and unnecessary portions (such as end portions shown in FIG. 4) of the acoustic matching layer 14 are removed. Thereby, as shown in FIG. 5, the ultrasonic probe in which the acoustic matching layer 14 is formed on the ultrasonic transducer array 10 is completed.

  Furthermore, the second and subsequent acoustic matching layers 14 and acoustic lenses can be formed by the same method as in steps S1 to S6. Here, (a) of FIG. 6 shows a cross section of the ultrasonic probe in which the acoustic lens 15 is formed on the acoustic matching layer 14, and (b) of FIG. 6 shows (a) of FIG. The cross section in the dashed-dotted line VI-VI shown in FIG. When forming the acoustic lens 15, the curvature of the acoustic lens 15 is designed so that the ultrasonic wave transmitted from the ultrasonic transducer array 10 converges to a desired depth in the completed ultrasonic probe, Accordingly, the inner wall of the mold (see FIG. 3) is formed.

  In the above, the case where the acoustic matching layer and the acoustic lens are formed on the ultrasonic transducer array in which a plurality of ultrasonic transducers are arranged has been described. However, the acoustic matching layer and the ultrasonic transmission surface of one ultrasonic transducer are arranged on the ultrasonic transmission surface. Even when the acoustic lenses are arranged, they can be formed by the same method.

  Further, in this embodiment, the case of manufacturing a convex ultrasonic probe in which a plurality of ultrasonic transducers are arranged on a convex surface has been described. However, the ultrasonic transducer arrangement surface has other shapes ( For example, even in the case of a flat shape or a concave shape, an ultrasonic probe can be manufactured by a similar method by changing the shape of the inner wall of the mold.

Next, a modification of the method for manufacturing an ultrasonic probe according to this embodiment will be described.
In the present embodiment, in step S4 of FIG. 1, the position of the ultrasonic transducer array 10 is set so that each of the time intervals T and T ′ shown in FIGS. 4B and 4C satisfies the equation (1). Combined. However, drive signals are simultaneously supplied to a plurality of ultrasonic transducers so that the reception timings of the ultrasonic echoes coincide with each other, that is, in FIGS. 4B and 4C, time t ₀ = time as will be t _1, it may be performed alignment of the ultrasonic transducer array 10. According to this modification, an acoustic matching layer having a uniform thickness can be easily formed.

Next, a method for manufacturing an ultrasonic probe according to the second embodiment of the present invention will be described.
Here, in the case of producing a high-frequency ultrasonic probe, the thickness of the acoustic matching layer is also reduced according to the frequency. Therefore, as shown in FIG. 3 and FIG. The time intervals T and T ′ until the ultrasonic echo is received become very short. In such a case, it is difficult to measure the time intervals T and T ′ due to the resolution of the oscilloscope, the influence of electromagnetic induction by the drive signal, and the like.

  Therefore, in the present embodiment, instead of disposing a liquid acoustic matching material in the mold 21 in step S3 of FIG. 1, as shown in FIG. (Referred to as “medium”) 31 is placed in the mold 21. In step S4, the ultrasonic transducer array 10 is aligned by transmitting and receiving ultrasonic waves in the low acoustic velocity medium.

  When the alignment is completed, the low sound velocity medium 31 is removed from the mold 21 while maintaining the relative position between the mold 21 and the ultrasonic transducer array 10. In that case, an opening 21a that can be opened and closed is formed in the mold 21 in advance, and the low-sonic medium 31 may be discarded through the opening 21a, or a highly volatile substance is used as the low-sonic medium 31. The low sound velocity medium 31 may be evaporated.

  Thereafter, as shown in FIG. 8, a liquid acoustic matching material 32 is injected into the mold 21 and cured while maintaining the position of the ultrasonic transducer array 10. Further, the cured acoustic matching material 32 is removed from the mold 21 and unnecessary portions such as end portions are removed, whereby the ultrasonic probe shown in FIG. 5 is completed.

  Here, as the low sound velocity medium 31, for example, diethyl ether (sonic velocity of 985 m / s), ethyl bromide (sonic velocity of 892 m / s), and a fluorine-based inert liquid (for example, Fluorinert manufactured by 3M Corporation in the United States) A liquid such as (FLUORINERT (registered trademark)) FC-40, sound velocity 641 m / s) is used. Among these, it is particularly preferable to use Fluorinert in terms of low sound speed, high safety, high volatility, and easy work.

Alternatively, as the low sound velocity medium 31, air (sound velocity 331.45 m / s), argon (Ar, sound velocity 319 m / s), carbon dioxide (sound velocity 268 m / s), chlorine (Cl ₂ , sound velocity 205.3 m / s). A gas such as s) may be used. In this case, since the speed of sound is further slowed down, it becomes easier to detect the time interval from the transmission of ultrasonic waves to the reception of ultrasonic echoes and the reception timing of ultrasonic echoes. When a gas other than air is used as the low acoustic velocity medium, it is necessary to fill the gas in the mold 21 and position the ultrasonic transducer array 10 in a sealed state.

Next, a method for manufacturing an ultrasonic probe according to the third embodiment of the present invention will be described.
In the present embodiment, when forming the acoustic matching layer or the like, as shown in FIG. 9, a mold 41 having a plurality of ultrasonic receiving elements 42 arranged at the bottom is used. An oscilloscope 24 is connected to these ultrasonic receiving elements 42.
When performing alignment of the ultrasonic transducer array 10 in step S4 of FIG. 1, ultrasonic waves transmitted from the plural ultrasonic transducers 12 are received by the ultrasonic wave receiving element 42. Then, by monitoring the reception timing with the oscilloscope 24, the distance between the surface of the ultrasonic transducer array 10 and the inner wall of the mold 41 is measured.

  According to this embodiment, by separately providing a receiving element for receiving ultrasonic waves, it is not necessary to provide the oscilloscope 24 and the switch 25 (see FIG. 3) on the ultrasonic transducer array 10 side, so that the configuration is simple. Become. Further, since the ultrasonic transducer 12 does not receive ultrasonic waves, it is possible to drive the ultrasonic transducer 12 using not only pulse waves but also continuous waves.

  In the present embodiment, since the time from when the ultrasonic wave is transmitted from the ultrasonic transducer 12 until the ultrasonic wave is received by the ultrasonic wave receiving element 42 is short, as in the second embodiment, It is preferable to perform alignment by disposing a low sound velocity medium in the mold 41.

  As described above, according to the embodiment of the present invention, an acoustic matching layer having a uniform and desired thickness and an acoustic lens having a desired curvature can be easily formed. In particular, since an extremely thin acoustic matching layer can be formed with high accuracy, an ultrasonic probe corresponding to a high frequency (for example, 20 MHz or more) can be easily manufactured at low cost and with a high yield. . In addition, since the ultrasonic transducer array and the acoustic matching layer, or the acoustic matching layer and the acoustic lens can be joined without using an adhesive, it is easy to design an ultrasonic probe. In addition, since no adhesive is required, reflection of sound waves at the interface between adjacent layers is suppressed, so that the sensitivity of the ultrasonic probe is improved and ultrasonic propagation due to unevenness of the adhesive is achieved. It becomes possible to suppress variation in efficiency and peeling of the joint portion.

  Further, the embodiment described above may be used when a backing layer is bonded to the ultrasonic transducer array. That is, a backing layer material (epoxy resin or the like) is placed in a mold in a liquid state, an ultrasonic transducer array is placed thereon and aligned, and then the backing layer material is cured. In this case, since the ultrasonic transducer array and the backing layer can be bonded without using an adhesive, the reflection of ultrasonic waves at their interface can be suppressed, and the ultrasonic waves can be attenuated efficiently, and the bonded portion can be bonded. Since it becomes difficult to peel off, there is an advantage that the durability of the ultrasonic probe can be improved.

  INDUSTRIAL APPLICABILITY The present invention can be used in a method for manufacturing an ultrasound probe used when performing extracorporeal scanning or intrabody scanning on a subject.

It is a flowchart which shows the manufacturing method of the probe for ultrasonic waves which concerns on the 1st Embodiment of this invention. It is a figure which shows the ultrasonic transducer array formed on the backing layer. It is a figure which shows the inside. It is a figure for demonstrating position alignment of the ultrasonic transducer array in a mold. It is a figure for demonstrating position alignment (state in which the position was adjusted) of the ultrasonic transducer array in a mold. It is sectional drawing which shows the probe for ultrasonic waves containing an ultrasonic transducer array and an acoustic matching layer. It is sectional drawing which shows the probe for ultrasonic waves in which the acoustic matching layer and the acoustic lens were formed. It is a figure for demonstrating the manufacturing method of the probe for ultrasonic waves which concerns on the 2nd Embodiment of this invention. It is a figure for demonstrating the manufacturing method of the probe for ultrasonic waves which concerns on the 2nd Embodiment of this invention. It is a figure for demonstrating the manufacturing method of the probe for ultrasonic waves which concerns on the 3rd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Ultrasonic transducer array 11 Backing layer 12 Ultrasonic transducer 13 Filler 14 Acoustic matching layer 21 and 41 Mold 21a Opening 22 and 32 Acoustic matching material (liquid)
23 Drive signal supply source (Pulsar)
24 oscilloscope 25 switch 31 low speed medium 42 ultrasonic receiving element

Claims (10)

At least one ultrasonic transducer that transmits and receives ultrasonic waves, and a member that is directly or indirectly disposed on the at least one ultrasonic transducer and that propagates ultrasonic waves transmitted from the at least one ultrasonic transducer In the method of manufacturing an ultrasonic probe,
Preparing a mold in which the shape of the member is formed, and disposing the at least one ultrasonic transducer in the mold;
In the mold, the ultrasonic wave is transmitted from the at least one ultrasonic transducer and the ultrasonic wave or the reflected wave of the ultrasonic wave is received, whereby the relative position between the mold and the at least one ultrasonic transducer is measured. Determining step (b);
(C) curing the member from a liquid state in the mold, the relative position of which is determined with respect to the at least one ultrasonic transducer;
A method for manufacturing an ultrasonic probe comprising: Step (a) comprises injecting the material of the member into the mold in a liquid state and disposing the at least one ultrasonic transducer in the liquid;
Step (c) includes curing the liquid injected into the mold in Step (a).
A method for manufacturing the ultrasonic probe according to claim 1. Step (a) includes disposing a medium in the mold having a sound velocity slower than in the member in a liquid state, and disposing the at least one ultrasonic transducer in the medium;
Step (c) includes removing the medium disposed in the mold in Step (a) and injecting the material of the member into the mold in a liquid state and curing the material.
A method for manufacturing the ultrasonic probe according to claim 1.   The method of manufacturing an ultrasonic probe according to claim 3, wherein the medium includes diethyl ether, ethyl bromide, a fluorine-based inert liquid, air, argon gas, carbon dioxide gas, or chlorine gas.   Step (b) transmits an ultrasonic wave from the at least one ultrasonic transducer, and the at least one ultrasonic transducer receives an ultrasonic echo generated by the reflection of the ultrasonic wave on the inner wall of the mold. The method for manufacturing an ultrasonic probe according to any one of claims 1 to 4, further comprising: determining the relative position based on a time interval until.   Step (b) transmits ultrasonic waves from the at least one ultrasonic transducer, and based on a time interval until the ultrasonic waves are received by at least one ultrasonic receiving element provided on the inner wall of the mold. The method for manufacturing an ultrasonic probe according to claim 1, comprising determining the relative position.   Step (b) transmits a plurality of ultrasonic waves from a plurality of ultrasonic transducers substantially simultaneously, and an ultrasonic echo generated by the reflection of the plurality of ultrasonic waves to the inner wall of the mold is converted into the plurality of ultrasonic waves. The method for manufacturing an ultrasonic probe according to claim 1, comprising determining the relative position so that the relative positions are received substantially simultaneously by a transducer.   In step (b), a plurality of ultrasonic waves are transmitted from a plurality of ultrasonic transducers substantially simultaneously, and the plurality of ultrasonic waves are received substantially simultaneously by a plurality of ultrasonic receiving elements provided on the inner wall of the mold. The method for manufacturing an ultrasonic probe according to claim 1, comprising determining the relative position.   The method for manufacturing an ultrasonic probe according to claim 1, wherein the member is an acoustic matching layer.   The method for manufacturing an ultrasonic probe according to claim 1, wherein the member is an acoustic lens.

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