WO2005034576A1

WO2005034576A1 - Ultrasonic transducer and ultrasonic treatment device employing it

Info

Publication number: WO2005034576A1
Application number: PCT/JP2004/004705
Authority: WO
Inventors: Jun Kubota; Kazunari Ishida; Shinichiro Umemura; Takashi Azuma
Original assignee: Hitachi Medical Corporation
Priority date: 2003-10-02
Filing date: 2004-03-31
Publication date: 2005-04-14
Also published as: JP4258022B2; JPWO2005034576A1

Abstract

An ultrasonic transducer comprising an oscillator array (6) provided with a plurality of oscillators (11) arrayed along a line or a curve wherein an acoustic lens (12) formed of a material harder than resin is provided on the ultrasonic wave radiating surface side of each oscillator (11), each oscillator has a width W in the arranging direction of the oscillator array equal to the width of the acoustic lens, and the acoustic lens has a concave surface recessed in the direction perpendicular to the arranging direction. The ultrasonic wave is focused at high density and the focal point of the ultrasonic wave is variably controlled electronically over a wide range.

Description

Description Ultrasonic transuser and ultrasonic therapy equipment using the same

The present invention relates to an ultrasonic transducer and an ultrasonic treatment device using the same. Background art

Generally, the treatment using ultrasonic waves includes heating treatment or baking using heat generated by irradiation of ultrasonic waves;): shaking treatment, crushing treatment for crushing stones and the like by the impact of ultrasonic waves, and the like. Ultrasound transducers used for such ultrasonic treatment are of a fixed focus type (for example, see Patent Document 1, Patent Document 2 β), and variable in order to focus ultrasonic waves on a target treatment site. A focus type (for example, see Patent Literature 2, Patent Literature 3, and Patent Literature 4) or a type using an acoustic lens (for example, see Patent Literature 5) has been proposed.

Patent Document 1 Japanese Patent Application Laid-Open No. 2000-9333429 (Paragraph "0000", FIG. 5) Patent Document 2 Japanese Patent Application Laid-Open No. Hei 10-3005041 (Paragraph 0 9 ", Figure 1) Patent Document 3 Japanese Patent Application Laid-Open No. 11-3113831 (Paragraph" 0 33 ", Figure 3) Patent Document 4 Japanese Patent Application Laid-Open No. 6-2851007 (Paragraph "0 0 1 7", "0 0 1 8", Figure 2)

Patent Document 5 Japanese Patent Application Laid-Open No. H11-509409 (page 8, FIG. 1)

The ultrasonic transgene user used for such an ultrasonic treatment usually includes an ultrasonic transducer for observation and treatment which is integrally incorporated, and is used for imaging by the ultrasonic transgene user for observation. While observing the tomographic image of the treatment site, high-power treatment ultrasonic waves are radiated from the treatment ultrasonic transducer to the target treatment site to perform treatment. Therefore, the ultrasonic transducer for observation While the target treatment site is being observed by the camera, it is necessary to match the focal point of the ultrasonic wave emitted from the ultrasonic transducer for treatment with the target treatment site. However, since the focal point of the therapeutic ultrasonic wave does not always coincide with the target treatment site, the fixed focal point type is preferably a variable focal point type that can electronically variably control the focal point as a therapeutic ultrasonic transducer. In other words, the variable focus type generally forms an array by arranging a plurality of transducers in a predetermined shape, and controls the phase and amplitude of the ultrasonic wave driving each transducer of this array for each transducer. In addition, the ultrasonic waves emitted from each transducer can be focused on a specific focal point, and the focal position can be changed.

By the way, in ultrasonic treatment, for example, in the case of ablation treatment, a so-called HIFU (High Intensity Focused Ultrasound) method of focusing high-intensity ultrasonic waves at a small focal point at high density is adopted. This HIFU has a relatively high frequency range from 500 MHz to 5 MHz, whereas the ultrasound used in ordinary ultrasound diagnosis ranges from 1 MHz to 20 MHz. Is used. Therefore, in ultrasonic treatment, it is required to focus ultrasonic waves with a longer wavelength than / Ultrasonic diagnosis at / J and a higher focal point with high density. Therefore, it is necessary to improve the control accuracy of electronic focus control and to precisely and variably control the focus over a wide range.

However, conventional ultrasonic transducers for therapy have not always been able to adequately meet these demands. For example, in the case of an Anyura-array type (Patent Document 3), it is difficult to reduce the size of the vibrator, since it is necessary to perform curved processing on the vibrator, so it is difficult to narrow the focal diameter. It is. On the other hand, in the linear array type, since the vibrator can be formed only by linear processing, the arrangement pitch of a plurality of vibrators can be reduced, and the diameter of the focal point can be reduced. Further, since a plurality of transducers are arranged in a line, a backing material such as an annular array is not necessarily required, so that a decrease in efficiency of electroacoustic conversion can be prevented. However, in the case of a linear array, ultrasonic waves can be focused by electronic scanning in an arrangement direction of a plurality of transducers (hereinafter, referred to as a major axis direction), but in a direction orthogonal to the major axis direction (hereinafter, short axis direction). In the axial direction, ultrasonic waves cannot be focused electronically. Therefore, in the short axis direction of the vibrator, it is conceivable to focus the ultrasonic waves by using an acoustic lens, as in the case of a diagnostic ultrasonic transuser. Usually, since the acoustic lens is provided on the side in contact with the living body as the subject, a material (for example, resin) having an acoustic impedance close to the acoustic impedance of the living body (typically, the impedance of water) is used. It is formed. However, since the therapeutic ultrasound has a high power, if it is formed of a relatively soft material such as resin, the loss due to the acoustic lens increases, and the heat generated by the loss becomes a new problem.

Therefore, in order to suppress the increase in loss due to the acoustic lens, the acoustic lens must be formed of a material having a higher hardness than the resin (for example, metal or ceramic). However, the acoustic impedance of high-hardness material is not close to the acoustic impedance of a living body, so the traveling wave of ultrasonic waves emitted from the vibrator is reflected in various ways at the interface between the acoustic lens and the living body, etc. Conversion takes place. This mode conversion causes a grating phenomenon that produces multiple focal points, which lowers the focusing efficiency of ultrasonic waves and limits the variable range of force and focus.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an ultrasonic transducer capable of focusing ultrasonic waves at high density and electronically variably controlling the focal point of the ultrasonic waves, and an ultrasonic treatment using the same. It is to provide a device. Disclosure of the invention

In order to achieve the above object, the present invention provides an ultrasonic transducer having a vibrator array in which a plurality of vibrators are arranged along a straight line or a curved line. An acoustic lens formed of a material harder than resin is provided on the surface side, and the width of each of the vibrators in the arrangement direction of the vibrator array and the width of each of the acoustic lenses are formed to be the same, and Each of the acoustic lenses is characterized in that its thickness in a direction perpendicular to the arrangement direction is formed in a concave shape.

As described above, since the acoustic lens is formed of a material (for example, metal or ceramic) harder than resin, an increase in loss due to the acoustic lens can be suppressed, and the problem of heat generation can be reduced. Moreover, the acoustic lens is provided separately for each transducer. In other words, the width of the acoustic lens in the array direction was the same as the width of each transducer, so that the spread of reflected waves caused by differences in acoustic impedance was kept within a narrower width than the wavelength. Can be As a result, the occurrence of the grating phenomenon due to the mode conversion can be minimized.

Further, since the ultrasonic transducer of the present invention is configured to include a transducer array in which a plurality of transducers are arranged along a straight line or a curved spring, basically, the plurality of transducers are excited. By electronically controlling the phase and amplitude of the generated ultrasonic waves, the focus position (focal point) of the ultrasonic waves can be variably controlled over a wide range. In addition, since the acoustic lens has a concave thickness in the direction perpendicular to the arrangement direction, it can also focus ultrasonic waves in the short-axis direction perpendicular to the transducer array arrangement direction. Waves can be focused at high density.

In this case, it is preferable that the width of the vibrator in the arrangement direction is set to a width smaller than the wavelength of the ultrasonic wave emitted from the vibrator. According to this, the array density of the transducers is improved, and the size of the focal point (focal diameter) where the ultrasonic waves emitted from each transducer overlap can be reduced. Can be made higher energy density.

Further, it is preferable to provide a plate wave preventing layer formed of a material having an acoustic impedance between the acoustic lens and the living body on the ultrasonic emission surface side of the acoustic lens. The acoustic lens is formed of a layer having an equal thickness parallel to the ultrasonic emission surface of the acoustic lens. As a result, the difference in acoustic impedance between the acoustic lens and the living body can be reduced by the plate wave prevention layer, so that the energy of the sound wave cannot be confined in the acoustic lens. As a result, a plate wave can be prevented, and the influence of the dripping phenomenon caused by the mode conversion of the acoustic lens can be further reduced.

Further, an ultrasonic transducer can be formed by including a plurality of transducer arrays configured as described above. In this case, it is preferable that the normal lines of the ultrasonic emission surfaces of the transducer arrays are provided so as to cross each other. Alternatively, it is preferable to arrange the ultrasonic emission surface of each transducer array in contact with the same virtual circle or virtual ellipse. In other words, the focal point of the ultrasonic waves emitted from the plurality of transducer arrays falls within the desired irradiation position range. A plurality of transducer arrays are arranged obliquely so as to face. With this configuration, the ultrasonic waves emitted from the plurality of transducer arrays can be focused on the same focal point. As a result, it is possible to reduce the decrease in the focusing efficiency due to the movement of the focal point, and to widen the effective variable range of the focal point, so that the density of the ultrasonic waves irradiated to the target treatment site can be further increased. The focus position can be variably controlled over a wider range.

In addition, the ultrasonic therapy apparatus of the present invention can be focused on the ultrasonic waves at a high density by using the ultrasonic transducer of the present invention, and can focus the ultrasonic waves in a wide range. Electronically variable control can be realized. As a result, it becomes possible to realize an ultrasonic treatment apparatus that can sufficiently satisfy the requirements of the HIFU method, which is one of the increasingly effective ultrasonic treatment methods. Brief Description of Drawings

FIG. 1 is a block diagram showing an ultrasonic therapy apparatus according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of the head of FIG. 1 including the ultrasonic transducer of the present invention.

FIG. 3 is a vertical cross-sectional view of a part of the transducer play included in the ultrasonic transuser according to one embodiment of the present invention.

FIG. 4 is a perspective view schematically showing an external shape around one vibrator of FIG. FIG. 5 is a perspective view illustrating a method for manufacturing a transducer array according to the present invention.

FIG. 6 is a diagram illustrating the detailed configuration and operation of the transducer array 6 incorporated in the head shown in FIG.

FIG. 7 is a plan view of the head of FIG. 6 as viewed from the focal point F side.

FIG. 8 is a view for explaining the configuration and operation of a transducer array 6 incorporated in a head according to another embodiment of the present invention.

FIG. 9 is a plan view of the head of FIG. 8 viewed from the focal point F side. BEST MODE FOR CARRYING OUT THE INVENTION

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

FIG. 1 is a schematic configuration diagram showing the entirety of an ultrasonic treatment apparatus to which an ultrasonic transducer according to an embodiment of the present invention is applied. As shown, an ultrasonic therapy apparatus, an ultrasonic therapy applicator 2 having a head 1 configured using the ultrasonic transducer according to the present invention, an ultrasonic diagnostic apparatus 3, The control / treatment planning section 4 is provided. The head 1 is provided with a groove having an array type treatment / observation head. In addition, a positioning mechanism 5 is incorporated in the body of the ultrasonic therapy applicator 2 in the housing 2 in connection with the head 1. The positioning mechanism 5 is configured to control the axial position of the head 1 and the rotational phase around the axis. The ultrasonic diagnostic apparatus 3 includes a multi-channel power amplifier, and includes an ultrasonic signal for observation that excites the observation head of the head 1 and a therapeutic ultrasonic signal that excites the treatment head. It is configured to generate ultrasonic signals and supply them to those heads. Then, the ultrasonic diagnostic apparatus 3 reconstructs the in-vivo image of the treatment target patient based on the ultrasonic signal output from the observation head, and also excites the treatment head to place the treatment ultrasonography at the treatment target site. It is configured to emit a sound wave. Treatment

The treatment planning unit 4 captures the in-vivo image data of the patient transferred from the ultrasonic diagnostic apparatus 3 via a transmission line (for example, Ethernet), and drives the positioning mechanism unit 5 by program control. The head 1 is configured to be positioned by moving in the longitudinal direction of the head 1 and rotating and scanning around the axis, thereby determining the position of the head 1 at the treatment target site. In addition, the ultrasonic diagnostic apparatus 3 and the treatment control / inspection planning unit 4 transmit and receive control signals such as freeze via a signal transmission path using a communication protocol such as RS232C. Is configured.

FIG. 2 shows a schematic configuration diagram of a cross section of the head 1. The head 1 has a pair of therapeutic transducer arrays 6 for emitting therapeutic ultrasonic waves in a housing formed in a hollow cylindrical shape, and an observation transducer arranged between the pair of therapeutic transducer arrays 6. It has a vibrator array 7. The transducer array for observation 7 constitutes an ultrasonic transuser that transmits and receives ultrasonic waves for observation for obtaining an in-vivo image of a patient. FIG. 3 is an enlarged longitudinal sectional view of a part of the transducer array 6 for treatment shown in FIG. 2, and FIG. 4 is a perspective view around one transducer. As shown in the figures, the transducer array 6 is formed by arranging a plurality of transducers 11 along a straight line extending left and right in the figures with a gap therebetween. An acoustic lens 12 is provided on the ultrasonic emission surface side (upper side in the figure) of each transducer 11. Here, the width of each acoustic lens 12 in the arrangement direction is formed to be the same as the width W of each transducer in the arrangement direction. Further, in the present embodiment, the plate wave preventing layer 13 is provided on the ultrasonic wave emitting surface side of each acoustic lens 12 so as to overlap. The combined body 15 composed of the vibrator 11, the acoustic lens 12, and the surfacing lb layer 13 thus formed is fixed by supporting the back side of the vibrator 11 1 on the upper surface of the backing material 14. Have been. The gap between each combination 15 may be an air gap, but it is possible to achieve moisture proof and waterproof by filling with a filling neo 18.

As shown in FIG. 4, the vibrator 11, the acoustic lens 12, and the plate wave prevention layer 13 are arranged on both end faces in the direction (short axis direction) orthogonal to the arrangement direction (long axis direction). The supporting side supports 16 are arranged.

The vibrator 11 can be configured using a well-known piezoelectric element. For example, JE ceramics PZT, PZLT, piezoelectric single crystal PZN-PT, VDF or the like, or a composite piezoelectric layer composed of them and a resin can be used. The acoustic lens 12 is used for focusing in the direction (short axis direction) orthogonal to the array direction (long axis direction) of the transducers of the oscillator array 6, but is used for a therapeutic ultra-high power. In order to reduce heat loss due to sound waves, it is formed using a material that is harder than a resin material such as silicon rubber. Specifically, it is preferable to use a metal material or a ceramic material. The plate wave prevention layer 13 is provided to match the acoustic impedance between the acoustic lens 12 and the living body, and may be formed of a material having an acoustic impedance between the acoustic lens and the living body. preferable. Specifically, to form by using the diffused powder aluminum or metal resin ^ ¹ better yet. The filler 18 is a solid material such as a resin material through which sound is difficult to pass, and is formed of a material different from a vibrator or an acoustic lens. For example, it can be formed of a material having high attenuation of ultrasonic waves and containing air bubbles. The backing material 14 has a large ultrasonic attenuation, and the vibration KJ element 1 1 is formed using a material that attenuates ultrasonic waves emitted in the rear direction. The backing material 14 is not always necessary in a linear array in which the transducers 11 are linearly arranged, and is provided for manufacturing reasons to be described later. If the heat generation due to the decrease in the electro-acoustic conversion efficiency caused by the backing material 14 does not cause a problem, the backing material 14 may be used to reinforce the support.

Here, the shape and dimensions of the vibrator 11 and the acoustic lens 12 of the present embodiment will be described. The vibrator 11 is formed in an elongated rectangular parallelepiped having a width W, a length L, and a height H. The width W of the vibrator 11 is narrower than the wavelength of the ultrasonic wave radiated from the vibrator 11 (normally in water for medical use). Specifically, the relationship of λ> Ψ> λΖ2 is selected for the wavelength λ of the ultrasonic wave. Similarly, the acoustic lens 12 is also formed to have a width W, a length L, and a height H ′ at both ends. The acoustic lens 12 is formed in a concave shape so that the thickness in the direction orthogonal to the arrangement direction is thinner at the center and thicker at both ends, and the ultrasonic wave emitted from the oscillator 11 is short-axis. It has the function of focusing in the direction.

Therefore, the superposed surfaces of the acoustic lens 12 and the vibrator 11 have the same shape and the same size. The plate wave prevention layer 13 also has a width W and a length L, and is provided so as to overlap the acoustic lens 12. That is, the vibrator 11 is formed at least in a relationship of A> W, and the acoustic lens 12 and the plate wave prevention layer 13 are also formed by dividing the vibrator 11 into the same width W.

As described above, by forming the width of the vibrator 11 and the acoustic lens 12 to be the same, according to the ultrasonic transducer for treatment of the present embodiment, the acoustic impedance of the acoustic lens 12 and the living body is changed. Various spreads of the reflected wave generated in the acoustic lens 12 due to the difference can be suppressed within a width smaller than the wavelength of the acoustic lens 12. As a result, the occurrence of mode conversion can be effectively suppressed, and the occurrence of the grating phenomenon can be minimized. Therefore, while the acoustic lens 12 can be formed of a high-hardness material to increase the lens erection rate, the mode conversion caused by the formation of the high-hardness material can be suppressed and the ultrasonic wave can be reduced. The high-density focusing and the variable focus range can be widened by effectively avoiding the reduction of the focusing efficiency and the limitation of the variable focus range. In particular, according to the present embodiment, since the plate wave prevention layer 15 is provided, the occurrence of mode conversion can be further suppressed, the density can be further improved, and the variable focus range can be further expanded. it can. In other words, the plate wave prevention layer 13 plays a role of preventing the energy of the sound wave from being confined in the acoustic lens 12, thereby generating a plate wave in the short axis direction of the acoustic lens 12. Can be prevented. Therefore, the plate wave prevention layer 13 has an acoustic impedance intermediate between the living body or the binder (for example, water) and the acoustic lens 12, and has an equal thickness parallel to the ultrasonic emission surface of the acoustic lens 12. Layer. According to this, the difference in acoustic impedance between the acoustic lens 12 and the living body can be mitigated by the plate wave prevention layer 13, and the effect of the grating phenomenon caused by the mode conversion of the acoustic lens 12 is further reduced. Can be reduced. If A> W is set to prevent the mode conversion of the acoustic lens 12, the pitch of the vibrator 11 is sufficiently reduced. As a result, the aperture diameter of the focal point of the therapeutic ultrasonic wave can be reduced, the required number of transducers 11 can be minimized, and the cost can be reduced. In consideration of the cost increase factor, the width of the vibrator 11 is preferably set to W> AZ2, and the effect of avoiding the grating phenomenon can be obtained.

According to the ultrasonic transducer of the present embodiment configured as described above, as shown in FIG. 3, the phase (delay time) and the amplitude of the ultrasonic wave applied to each of the transducers 11 in a linear array are changed. By controlling individually, the ultrasonic waves emitted from each transducer 11 in the long axis direction of the array transducer 6 can be focused on the focal point F as shown by the arrow. In the short axis direction, the lens can be focused toward the focal point F by the lens action of the ultrasonic wave emitting surface of the acoustic lens 12 formed on the concave curved surface.

Next, a method of manufacturing the transducer array 6 of FIG. 3 will be described. First, as shown in the perspective view of FIG. 5, the vibrator 11 is formed by filling an elongated flat vibrator material 19 with the arrangement interval of the vibrators 11, that is, the filler 18 shown in FIG. A groove 20 having a width corresponding to the portion indicated by the arrow is cut out to form an array including a plurality of transducers 11. At this time, each vibrator 11 is formed with a groove 20 so as to remain a continuous portion 2 1; ^ continuous in the width direction at both ends in the short axis direction. The workability can be enhanced by the continuous portion 21. Ma Although not shown, the manufacturing method of the acoustic lens 12 and the plate wave prevention layer 13 is the same, and the same long and flat acoustic lens material or plate wave prevention layer material as the vibrator material 19 is used. Cut out a groove having the same width as the arrangement interval of the vibrator 11. In this case, cut-out is performed so that the continuous portion at both ends in the short-axis direction is left, and an array including a plurality of acoustic lenses 12 or plate wave prevention layers 13 is formed. In FIG. 4, illustration of a continuous portion 21 of the vibrator 11, an acoustic lens 12, and a continuous portion of the plate wave prevention layer 13 is omitted.

The vibrator array 6 is formed by bringing the vibrator 11 thus formed, the acoustic lens 12 and the array of the plate wave preventing layer L 3 into close contact with each other and joining them. At this time, it is important to join the vibrator 11, the acoustic lens 12, and the groove 20 of the plate wave preventing layer 13 so that they exactly match. Separately, after bonding the vibrator material, the acoustic lens material, and the plate wave preventing layer material, the grooves for forming the array of each element may be cut out.

Next, referring to FIGS. 6 and 7, a detailed configuration and operation of the vibrator array 6 incorporated in the head 1 shown in FIG. 2 will be described. As shown in FIG. 6, the pair of transducer arrays 6 are arranged at symmetrical positions with respect to the transducer array 7 for observation, with the long axis direction inclined at an angle with respect to the axis of the head 1. That is, the ultrasonic emission surfaces of the pair of transducer arrays 6 are arranged so as to be inclined so as to face each other, and are arranged such that the lines of the ultrasonic emission surfaces intersect each other at Fb. In other words, the center positions of the ultrasonic emission surfaces of the pair of transducer arrays 6 are arranged in contact with the same virtual circle (or virtual ellipse). FIG. 7 is a view of the head 1 viewed from the focal point F side of FIG. Is formed so as to be able to be stored in the housing.

The transducer array 6 is formed so that the focal point can be varied in a range between a deep focal point Fc and a shallow focal point Fa. In particular, it is formed so that supersonic waves can be most efficiently focused at the central focal point Fb between them. Therefore, the focusing efficiency decreases from the central focal point toward the deep focal point Fc or the shallow focal point Fa. By arranging a pair of transducer arrays 6 having such focusing characteristics as shown in the figure, it is possible to reduce a decrease in the focusing efficiency due to the movement of the focal point. As a result, the effective variable range of the focal point can be widened. In other words, such effects It is preferable to arrange the pair of transducer arrays 6 so as to face the common focal point movement range in which the ultrasonic waves emitted from each transducer array 6 converge. The variable range of the focal point is also related to the length L of the transducer 11, that is, the ratio of the short axis diameter of the transducer array 6 to the length of the transducer array 6 in the long axis direction, that is, the long axis diameter. I have. That is, in the major axis direction of the transducer array 6, the focal position can be changed by focusing the ultrasonic waves by electronic control. On the other hand, the acoustic lens 12 has a fixed focal point in the minor axis direction of the transducer array 6. Therefore, by setting the long axis diameter larger than the short axis diameter, the variable range of the focal point can be further widened. In addition, the transducer array 7 for observation basically uses an ultrasonic transducer for diagnosing Shuyaguchi.

According to the treatment head 1 provided with the ultrasonic transducer user configured as described above, the ultrasonic waves emitted from the pair of transducer arrays 6 can be focused on the same focal point. As a result, it is possible to reduce the decrease in focusing efficiency due to the movement of the focal point and to widen the effective variable range of the focal point, so that the density of the ultrasonic waves irradiated to the treatment site can be further increased. At the same time, the focal position can be variably controlled over a wider range.

In particular, since the width W of the transducer 11 in the major axis direction is set to a width smaller than the wavelength of the ultrasonic wave, the density of the transducers in the major axis direction of the transducer array 6 is increased, and the aperture diameter of the focus is reduced. Can be reduced. As a result, the density of the ultrasonic wave applied to the treatment site can be further increased.

Also, since the acoustic lens 12 for focusing the ultrasonic waves in the short axis direction is made of a material harder than the resin material and is separated to have the same width as the width of the exit surface of the vibrator 11, the acoustic The various spreads of the reflected wave generated in the lens 12 are suppressed to a width narrower than the wavelength of the acoustic lens 12 to effectively suppress the occurrence of mode conversion and minimize the occurrence of the dripping phenomenon. Can be As a result, it is possible to further reduce the aperture diameter of the focal point and further increase the density of ultrasonic waves. This effect is achieved by providing a plate wave prevention layer 13 formed of a material having an acoustic impedance between the living body and the acoustic lens 12 (for example, an intermediate value) on the surface of the acoustic lens 12. This facilitates more effectively. In the above description, the focus of the pair of transducer arrays 6 is set to the same focus to improve the energy density of the ultrasonic wave at the focus.However, the method of using the ultrasonic transducer of the present invention is as follows. It is not limited to this. That is, according to the transducer array 6 of the present invention, since the diameter of the focal point can be reduced and the density of the ultrasonic energy can be increased, the focal point of each transducer array 6 can be controlled at a different location. However, a plurality of treatment sites can be treated at the same time. For example, as shown in FIG. 6, the focus of one transducer array 6 is controlled to Fb or Fc, the focus of the other transducer array 6 is controlled to Fa, and two treatment sites are controlled. Can be treated. According to this, the treatment time can be shortened.

Next, FIGS. 8 and 9 show another embodiment of the head 1 shown in FIG. Details The configuration and operation will be described. The embodiment shown in FIGS. 8 and 9 differs from the embodiment shown in FIGS. 6 and 7 in that the ultrasonic emission surfaces of the pair of transducer arrays 6 are formed as curved surfaces in the long axis direction. . That is, each transducer array 6 is formed by arranging a plurality of transducers 11 along a curved line with a gap therebetween.

Thus, according to the present embodiment, the ultrasonic waves emitted from the plurality of transducers 11 and the acoustic lens 12 are efficiently focused on the focal point as compared with the embodiment of FIG. Can be done.

The embodiment shown in FIG. 2 has a configuration of a vibrator array 6 in which an acoustic lens 12 having the same width is combined with each vibrator 11 and a configuration in which a pair of the vibrator arrays 6 are symmetrically arranged in an inclined manner. The head 1 formed by combining the above has been described. However, the present invention is not limited to this, and can be applied to the ultrasonic transducer alone including the transducer array 6 of the embodiment of the present invention. Also, an ultrasonic transdie user can be configured by independently applying a conventional configuration in which a pair of transducer arrays are symmetrically arranged and inclined. In addition, the head is not limited to a pair of transducer arrays, and a head can be configured by providing three or more transducer arrays for treatment. Further, the ultrasonic transducer of the present invention is not limited to medical applications, but can be applied to other applications that make use of its features.

Claims

The scope of the claims

1. For an ultrasonic transducer user equipped with a transducer array consisting of multiple transducers arranged in a straight line or curve,

Each of the transducers is provided with a wide acoustic lens formed of a material harder than resin on the ultrasonic wave emitting surface side, and the width of each transducer in the arrangement direction of the transducer array and the width of each of the acoustic lenses An ultrasonic transducer having the same width, and wherein each of the acoustic lenses is formed to have a concave thickness in a direction orthogonal to the arrangement direction.

2. A plate wave preventing layer is provided on the ultrasonic wave emitting surface side of each of the acoustic lenses, and the plate wave preventing layer is formed of a material having an acoustic impedance between the acoustic lens and a living body. 2. The ultrasonic transducer according to claim 1, wherein the ultrasonic transducer is an ultrasonic transducer.

3. The method according to claim 1, wherein the plurality of transducer arrays are formed, and the plurality of transducer arrays are provided such that normals of ultrasonic emission surfaces of the transducer arrays intersect each other. The described ultrasonic transducer.

4. A plurality of the transducer arrays are formed, and the plurality of transducer arrays are arranged with the ultrasonic emission surface of each transducer array in contact with the same virtual circle or virtual ellipse. 3. The ultrasonic transducer according to claim 1, wherein:

5. The ultrasonic transformer according to claim 1, wherein a width of each transducer in the arrangement direction is set to be smaller than a wavelength of an ultrasonic wave emitted from each transducer. Juisa.

6. An ultrasonic transuser having a transducer array in which a plurality of transducers are arranged along a straight line or a curve, and a means for generating a therapeutic ultrasound signal for driving the ultrasonic transducer. In the equipped ultrasonic therapy device,

The ultrasonic transducer is provided with an acoustic lens formed of a material harder than a tree on the ultrasonic emission surface side of each of the transducers, and each of the transducers in the array direction of the transducer array is provided. The width of each acoustic lens is the same as the width of each acoustic lens, and the thickness of each acoustic lens in the direction perpendicular to the arrangement direction is concave. An ultrasonic therapy apparatus characterized by the following.

7. The ultrasonic transducer has a plate wave preventing layer provided on the ultrasonic wave emitting surface side of each acoustic lens, and the plate wave preventing layer is made of a material having an acoustic impedance between the acoustic lens and a living body. 7. The ultrasonic treatment device according to claim 6, wherein the ultrasonic treatment device is formed by:

8. The ultrasonic transducer is formed having a plurality of the transducer arrays, and normal lines of ultrasonic emission surfaces of the plurality of transducer arrays are provided so as to intersect with each other. 7. The ultrasonic treatment device according to claim 6, wherein:

9. The ultrasonic transducer is formed by including a plurality of the transducer arrays, and the plurality of transducer arrays are arranged so that the ultrasonic emission surfaces of the respective transducer arrays have the same virtual circle or virtual ellipse. 7. The ultrasonic treatment device according to claim 5, wherein the ultrasonic treatment device is disposed in contact with the ultrasonic treatment device.

10. The ultrasonic transducer according to claim 1, wherein the width of each transducer in the arrangement direction is set to be smaller than the wavelength of the ultrasonic wave emitted from each transducer. Item 7. The ultrasonic treatment device according to item 5 or 6.