Ultrasound probe

Abstract

To properly measure the temperature of a backing having thermal anisotropy, in an ultrasonic probe.SOLUTION: A main-backing 22 is provided on the rear side of an electronic circuit 37. The main backing 22 has two outer surfaces (high heat conduction surfaces) 22a and 22b orthogonal to a direction Y and two outer surfaces (low heat conduction surfaces) orthogonal to a direction X. The two outer surfaces 22a and 22b are connected to a shell head 14 serving as a heat absorption member. A temperature sensor 200 is provided on the outer surface 22b. The shell head 14 has a recess for housing the temperature sensor 200.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present disclosure relates to an ultrasonic probe, and more particularly to a heat conduction structure within the ultrasonic probe.

Background Art

[0002] In ultrasonic inspection, an ultrasonic diagnostic apparatus is used. The ultrasonic diagnostic apparatus has an ultrasonic probe that transmits and receives ultrasonic waves. In recent years, ultrasonic probes equipped with two-dimensional vibration element arrays have been increasingly popular. Such ultrasonic probes are also called three-dimensional probes or 2D array probes. According to a 2D array probe, volume data can be acquired by two-dimensional scanning of an ultrasonic beam, or frame data can be acquired by one-dimensional scanning of an ultrasonic beam to which two-dimensional electronic focusing is applied.

[0003] An oscillator assembly including a vibration element array is provided within the ultrasonic probe. The oscillator assembly generally has a matching layer provided on the front side (biological side) of the vibration element array and a backing provided on the rear side (non-biological side) of the vibration element array. The backing attenuates unnecessary ultrasonic waves emitted from the vibration element array to the rear side thereof.

[0004] In the above 2D array probe, generally, the oscillator assembly has a two-dimensional vibration element array and an electronic circuit. In the electronic circuit, a plurality of transmission signals supplied to a plurality of vibration elements are generated, and a plurality of reception signals output from the plurality of vibration elements are processed. The electronic circuit is usually composed of one or more integrated circuits (specifically, one or more ASICs).

[0005] In a 2D array probe, a great deal of heat is generated in the two-dimensional vibration element array and the electronic circuit. In particular, the amount of heat generated in the electronic circuit is large. From the viewpoint of biological safety, it is necessary to maintain the temperature of the transmission and reception wave surfaces in the ultrasonic probe below a specified temperature. In order to effectively release the heat generated in the electronic circuit and the like to the outside, a heat conduction structure is provided within the ultrasonic probe.

[0006] The ultrasonic probe disclosed in Patent Document 1 has a vertically stacked array of vibrating elements, an ASIC, and a backing. Patent Document 1 does not disclose a heat conduction structure that utilizes the thermal anisotropy of the backing. The ultrasonic probe disclosed in Patent Document 2 has a backing in which a lead array is embedded. An electronic circuit is provided behind the backing. Patent Document 2 does not disclose a backing provided behind the electronic circuit. [Prior art documents] [Patent Documents]

[0007] [Patent Document 1] Patent No. 5972296 specification [Patent Document 2] Japanese Patent Publication No. 2017-70449 [Overview of the Initiative] [Problems that the invention aims to solve]

[0008] The purpose of this disclosure is to properly measure the temperature of a thermally anisotropic backing in an ultrasonic probe. [Means for solving the problem]

[0009] The ultrasonic probe according to this disclosure includes a vibrating element array, an electronic circuit provided behind the vibrating element array and electrically connected to the vibrating element array, and a backing provided behind the electronic circuit and attenuating ultrasonic waves from the vibrating element array, wherein the arrangement direction of the vibrating element array, the electronic circuit, and the backing is defined as the Z direction, the direction perpendicular to the Z direction is defined as the X direction, and the direction perpendicular to both the Z direction and the X direction is defined as the Y direction, and in the backing, the thermal conductivity in the Z direction and the thermal conductivity in the Y direction are both greater than the thermal conductivity in the X direction, and the backing is Two outer surfaces intersecting in the X direction, Two outer surfaces intersecting in the Y direction and, It has, The two outer surfaces intersecting in the X direction are each low-thermal-conductivity surfaces having a lower thermal conductivity than the two outer surfaces intersecting in the Y direction, and the two outer surfaces intersecting in the Y direction are each high-thermal-conductivity surfaces having a higher thermal conductivity than the two outer surfaces intersecting in the X direction.Intersecting in the aforementioned Y direction The aforementioned A temperature sensor is placed on at least one of the two outer surfaces. Furthermore, a heat-absorbing member is provided having two inner surfaces joined to the two outer surfaces perpendicular to the Y direction, and the heat-absorbing member includes a recess having a housing space for housing the temperature sensor, and the temperature sensor is separated from the inner surface of the recess. It is characterized by the following: [Effects of the Invention]

[0010] According to this disclosure, the temperature of a thermally anisotropic backing can be accurately measured in an ultrasonic probe. [Brief explanation of the drawing]

[0011] [Figure 1] This is a cross-sectional view showing the structure of an ultrasonic probe according to an embodiment. [Figure 2] This is an exploded perspective view showing the oscillator assembly. [Figure 3] This is a cross-sectional view showing the laminate. [Figure 4] This is an XZ cross-sectional view showing the tip of the ultrasonic probe according to the embodiment. [Figure 5] This is a schematic diagram showing the XY cross-section of the tip of the ultrasonic probe according to the embodiment. [Figure 6] This is a perspective view of the shell. [Figure 7] This is a YZ cross-sectional view showing an ultrasonic probe according to an embodiment. [Figure 8] This is a YZ cross-sectional view showing the arrangement of temperature sensors. [Figure 9] This is a diagram showing the first modified example. [Figure 10] This figure shows a second modified example. [Modes for carrying out the invention]

[0012] The embodiments will be described below with reference to the drawings.

[0013] (1) Outline of the Embodiment The ultrasonic probe according to the embodiment includes a vibration element array, an electronic circuit provided on the rear side of the vibration element array and electrically connected to the vibration element array, and a backing provided on the rear side of the electronic circuit for attenuating ultrasonic waves from the vibration element array. When the arrangement direction of the vibration element array, the electronic circuit, and the backing is defined as the Z direction, the direction orthogonal to the Z direction is defined as the X direction, and the direction orthogonal to the Z direction and the X direction is defined as the Y direction, in the backing, both the Z-direction thermal conductivity and the Y-direction thermal conductivity are larger than the X-direction thermal conductivity. The backing has two outer surfaces intersecting in the Y direction, and at least one of the two outer surfaces intersecting in the Y direction is provided with a temperature sensor.

[0014] In the above configuration, both of the two outer surfaces intersecting in the Y direction in the backing are high-thermal-conductivity surfaces and heat output surfaces when viewed relatively along. On the other hand, both of the two outer surfaces intersecting in the X direction in the backing are relatively low-thermal-conductivity surfaces. According to the above configuration, the temperature of the heat output surface can be detected by the temperature sensor.

[0015] The ultrasonic probe according to the embodiment includes a heat absorption member having two inner surfaces joined to two outer surfaces orthogonal to the Y direction. The temperature sensor is separated from the heat absorption member. According to this configuration, since the temperature sensor is separated from the heat absorption member, the temperature of the backing (the temperature at the interface between the backing and the heat absorption member) can be correctly measured. That is, the influence of the temperature gradient in the heat absorption member on the temperature sensor is reduced.

[0016] In the embodiment, the heat absorption member has a housing space for housing the temperature sensor. The temperature sensor is separated from the inner surface of the housing space. An air layer exists between the inner surface of the housing space and the outer surface of the temperature sensor. The air layer functions as a thermal insulation layer. When it is difficult to process the backing (especially forming a recess), a recess is formed in the heat absorption member. The inside of the recess functions as the above housing space. The temperature sensor is provided in a non-contact state with respect to the heat absorption member on a portion exposed in the recess within a specific outer surface of the backing.

[0017] In this embodiment, the outer surface on which the temperature sensor is located has an upper end close to the electronic circuit and a lower end farther from the electronic circuit. The temperature sensor is located at the lower end. Since the backing has high thermal conductivity in the Z direction, the temperature of the backing can be accurately measured even if the temperature sensor is located at the lower end of the outer surface. Such an arrangement allows for a shorter signal line length from the temperature sensor.

[0018] In this embodiment, the above-mentioned backing is the main backing. A sub-backing is provided between the electronic circuit and the main backing. In the sub-backing, both the thermal conductivity in the Z direction and the thermal conductivity in the X direction are greater than the thermal conductivity in the Y direction. Heat diffused in the X direction within the sub-backing is transferred to the heat-absorbing member via the main backing. The temperature sensor detects the temperature of the interface between the main backing and the heat-absorbing member. If the main backing has a high thermal conductivity in the Y direction, a specific outer surface on which the temperature sensor is provided can be considered the interface between the main backing and the heat-absorbing member.

[0019] (2) Details of the embodiment Figure 1 shows an ultrasound probe 10 according to an embodiment. The ultrasound probe 10 is connected to an ultrasound diagnostic device body (not shown). The ultrasound probe 10 and the ultrasound diagnostic device body constitute an ultrasound diagnostic device. The ultrasound diagnostic device is a medical device used in ultrasound examinations of a patient (living body). The ultrasound probe 10 has cables and connectors (not shown).

[0020] In Figure 1, the X direction is the first horizontal direction, the Y direction is the second horizontal direction, and the Z direction is the vertical direction. The three directions are orthogonal. The central axis of the ultrasound probe 10 is parallel to the Z direction. The X direction is the first electron scanning direction, and the Y direction is the second electron scanning direction.

[0021] Figure 1 shows the XZ cross-section of the ultrasonic probe 10. However, some components of the ultrasonic probe 10 are not shown. The ultrasonic probe 10 consists of a tip section 10A, a middle section 10B, and a rear section 10C. The tip section 10A is a bulging portion, and the middle section 10B is a constricted portion.

[0022] A shell 12 is provided inside the resin case 11. The shell 12 is a heat-absorbing member. The shell 12 is made of a metal with good thermal conductivity, specifically aluminum or the like. The shell 12 is composed of a shell head (tip) 14, an intermediate part 15, and a rear end 16. The shell 12 is a hollow member. The shell 12 has a shape that surrounds a rectangular prism-shaped cavity (internal space). At each position in the Z direction, the XY cross-section of the cavity is rectangular. The outer surface of the shell 12 and the inner surface of the resin case 11 are in close contact.

[0023] A transducer assembly 17 is placed inside the shell head 14. The transducer assembly 17 includes a two-dimensional vibrating element array as well as a backing member (backing set) 20 that attenuates unwanted ultrasonic waves. In the illustrated configuration example, the backing member 20 is composed of a sub-backing (first backing) 21 and a main backing (second backing) 22. Both the sub-backing 21 and the main backing 22 are composed of backings having thermal anisotropy. The sub-backing 21 has a first thermal anisotropy. The main backing 22 has a second thermal anisotropy different from the first thermal anisotropy. This will be described in detail later. The stacking direction in the transducer assembly 17 is the Z direction.

[0024] The oscillator assembly 17 has a laminate containing a two-dimensional vibrating element array and an electronic circuit composed of multiple ICs. The upper surface of the oscillator assembly 17 is covered with a protective layer 18. The surface of the protective layer 18 is the transmitting and receiving wavefront that comes into contact with the surface of the subject.

[0025] An FPC (flexible printed circuit board) 24 is provided between the laminate and the electronic circuit. The FPC 24 is a flexible sheet-like wiring member. In this embodiment, the FPC 24 is a multilayer FPC having multiple wiring layers. Its thickness is, for example, in the range of 0.1 to 0.5 mm. Its width in the Y direction is, for example, in the range of 10 to 20 mm.

[0026] The FPC24 has a horizontal section 26, a first drooping section 28, and a second drooping section 30. The first drooping section 28 and the second drooping section 30 are each provided with a plurality of connectors 32 and reinforcing plates 34. The upper end of the first drooping section 28 is the first vertical section. The upper end of the second drooping section 30 is the second vertical section.

[0027] Figure 2 shows the configuration of the oscillator assembly 17. As previously described, the oscillator assembly 17 has a laminate 36 containing a two-dimensional vibrating element array. An electronic circuit 37 is provided on the rear side (non-biological side) of the laminate 36. The electronic circuit 37 is composed of, for example, two ICs 38, 40 aligned in the X direction. Each IC 38, 40 has the function of generating multiple transmit signals to the two-dimensional vibrating element array and the function of processing multiple receive signals from the two-dimensional vibrating element array. The latter function includes a sub-beamforming function. The electronic circuit 37 may be composed of more ICs arranged in the X and Y directions.

[0028] A two-dimensional vibration element array is composed of multiple vibration elements (transducers) arranged in a first electron scanning direction (X direction) and a second electron scanning direction (Y direction). For example, a two-dimensional vibration element array is composed of tens, hundreds, thousands, tens of thousands, or more vibration elements. Alternatively, a one-dimensional vibration element array may be provided instead of a two-dimensional one. A one-dimensional vibration element array is composed of multiple vibration elements arranged in the X direction.

[0029] A horizontal portion 26 of the FPC 24 is sandwiched between the laminate 36 and the electronic circuit 37. The horizontal portion 26 performs functions such as signal connection and wiring pattern conversion. One end of the horizontal portion 26 is connected to the first hanging portion 28 via the first bent portion 24a. The other end of the horizontal portion 26 is connected to the second hanging portion 30 via the second bent portion 24b. The central axis of the horizontal portion 26 is parallel to the X direction. In other words, the alignment direction of the first hanging portion 28, the horizontal portion 26, and the second hanging portion is the X direction.

[0030] The sub-backing 21 has a plate-like shape. The sub-backing 21 has the effect of attenuating unwanted ultrasonic waves radiated backward from the two-dimensional vibrating element array. The sub-backing 21 has a first thermal anisotropy. Specifically, in the sub-backing 21, the thermal conductivity in the Z direction and the thermal conductivity in the X direction are greater than the thermal conductivity in the Y direction, respectively.

[0031] The sub-backing 21 exerts a heat conduction effect in the Z direction. Furthermore, as indicated by the symbol 42, the sub-backing 21 also exerts a heat diffusion effect in the X direction. The upper surface of the sub-backing 21 is joined to the electronic circuit 37, and the lower surface of the sub-backing 21 is joined to the upper surface of the main backing 22.

[0032] The main backing 22 has a rectangular parallelepiped shape. The main backing 22 has the effect of attenuating unwanted ultrasonic waves that enter through the sub-backing. The main backing 22 has a second thermal anisotropy that is different from the first thermal anisotropy described above. Specifically, in the main backing 22, the thermal conductivity in the Z direction and the thermal conductivity in the Y direction are greater than the thermal conductivity in the X direction, respectively.

[0033] The main backing 22 exhibits a heat conduction function in the Z direction, and as indicated by reference numeral 44, it also exhibits a heat conduction function in the Y direction. Heat is transferred to the shell head from the two outer surfaces (two sides) of the main backing 22 that are perpendicular to the Y direction. More specifically, the heat generated in the electronic circuit 37 (and the two-dimensional vibration element array) is transferred to the shell via the sub-backing 21 and the main backing 22, and that heat is absorbed by the shell. In this specification, orthogonality is one aspect of intersection.

[0034] The first thermal anisotropy of the secondary backing 21 is characterized by the Y direction, which is the direction of low thermal conduction. The second thermal anisotropy of the main backing 22 is characterized by the X direction, which is the direction of low thermal conduction. The two low thermal conduction directions are orthogonal to each other.

[0035] The thickness of the secondary backing 21 is less than the thickness of the main backing. The thickness of the secondary backing 21 is, for example, in the range of 1 to 5 mm. The thickness of the main backing is, for example, in the range of 10 to 15 mm.

[0036] In the illustrated configuration example, the width of the sub-backing 21 in the Y direction is equal to the width of the main backing 22 in the Y direction. Their widths are, for example, within the range of 10 to 20 mm. The width of the sub-backing 21 in the X direction is greater than the width of the main backing 22 in the X direction. Specifically, on both sides in the X direction, the sub-backing 21 protrudes by lengths corresponding to d1 and d2. A slit-like space is created directly below each protruding portion. The width of the sub-backing 21 in the X direction is, for example, within the range of 30 to 45 mm.

[0037] The secondary backing 21 and the primary backing 22 may each be composed of graphite blocks containing multiple graphenes. In the graphite block, each graphene is a sheet-like material consisting of numerous carbon atoms arranged planarly (in the i-direction and the j-direction). In the graphite block, the direction of arrangement of the multiple graphenes is the k-direction. Here, the i-direction, j-direction, and k-direction are orthogonal. A carbon block containing multiple planar graphite assemblies (see, for example, WO2018 / 074493) may be used as the backing.

[0038] The graphite block described above has good ultrasonic attenuation and good thermal conductivity. For example, the thermal conductivity in the i-direction and j-direction is in the range of 700 to 1000 (W / m / K), and the thermal conductivity in the k-direction is in the range of 10 to 20 (W / m / K). Materials to adjust acoustic impedance and ultrasonic attenuation may be added to the graphite block. Graphite blocks with thermal conductivity exceeding 1000 (W / m / K) in the i-direction and j-direction, or those with thermal conductivity below 700 (W / m / K) in the i-direction and j-direction, may also be used.

[0039] For example, in the electronic circuit 37, if only IC 38 releases a large amount of heat, according to this embodiment, as the heat is transferred through the sub-backing 21, it naturally diffuses in the X direction. This prevents heat from accumulating directly beneath IC 38. The heat diffused within the sub-backing 21 enters the main backing 22. The heat that enters is guided in the Y direction within the main backing 22. The guided heat moves towards the shell through the two heat output surfaces. The heat that enters the shell spreads throughout the entire shell. Through the outer surface of the shell, the heat is transferred to the resin case, and the heat is released to the outside from the entire outer surface of the resin case. Heat is also transferred from the shell to the probe cable, and the heat is released to the outside through the probe cable.

[0040] The secondary backing 21 and the main backing 22 exhibit extremely high thermal conductivity except in certain directions. Therefore, the above-described thermal conductivity mechanism provided within the ultrasonic probe efficiently dissipates the heat generated in the electronic circuit 37 and the two-dimensional vibrating element array to the outside, effectively lowering the temperature of the transmitting and receiving wavefronts in contact with the living body.

[0041] Figure 3 shows the laminate 36. The laminate 36 is composed of a reflective layer 52, a piezoelectric layer 50, a first matching layer 54, a second matching layer 56, a ground layer 60, and a third matching layer 62, all stacked in the Z direction.

[0042] The piezoelectric layer 50 is composed of a plurality of piezoelectric elements arranged in two dimensions. Each piezoelectric element is an electroacoustic conversion element. The reflective layer 52 is composed of a plurality of reflective elements arranged in two dimensions. Each reflective element is conductive. The reflective layer 52 can also be called a hard backing layer. The first matching layer 54 is composed of a plurality of first matching elements arranged in two dimensions. Each first matching element is conductive. The second matching layer 56 is composed of a plurality of second matching elements arranged in two dimensions. Each second matching element is conductive. A ground layer 60 is provided above the second matching layer 56. A third matching layer 62 is provided above the ground layer 60. A protective layer (not shown) is provided above the third matching layer 62. An FPC 24 is provided below the reflective layer 52. Reference numeral 64 indicates a single vibrating element or a portion containing a single vibrating element.

[0043] Figure 4 shows an XZ cross-section of the tip of an ultrasonic probe according to an embodiment. A transducer assembly 17 is located inside the shell head 14. The transducer assembly 17 includes a laminate 36, an electronic circuit 37, a secondary backing 21, and a main backing 22, all aligned in the Z direction. The FPC 24, which is a wiring member, consists of a horizontal portion 26, a first hanging portion 28, and a second hanging portion 30. The horizontal portion 26 is sandwiched between the laminate 36 and the electronic circuit 37. In the illustrated configuration example, the electronic circuit 37 consists of two ICs 38 and 40 aligned in the X direction.

[0044] The sub-backing 21 has two outer surfaces (two sides) perpendicular to the Y direction (the direction through which the paper penetrates), and two outer surfaces (two sides) perpendicular to the X direction. Each of these four sides is an exposed surface that does not exhibit heat conduction. The first bent portion 24a of the FPC 24 wraps around one end of the sub-backing 21 in the X direction. The second bent portion 24b of the FPC 24 wraps around the other end of the sub-backing 21 in the X direction.

[0045] The direction of the graphene arrangement in the sub-backing 21 is the Y direction. One end and the other end of the sub-backing 21 in the X direction are difficult to deform in the X direction. Therefore, even if a force (shear force) is applied to one end from the first bending portion 24a, that end will not easily deform. Similarly, even if a force (shear force) is applied to the other end from the second bending portion 24b, the other end will not easily deform.

[0046] The main backing 22 has two outer surfaces (two sides) 22a and 22b perpendicular to the Y direction (the direction through which the paper penetrates), and two outer surfaces (two sides) 22c and 22d perpendicular to the X direction. The two outer surfaces 22a and 22b perpendicular to the Y direction are relatively high thermal conductivity surfaces and function as thermal output surfaces. The two outer surfaces 22c and 22d perpendicular to the X direction are relatively low thermal conductivity surfaces. Each of the outer surfaces 22c and 22d does not have thermal conductivity. The direction of the graphene arrangement in the main backing 22 is the X direction.

[0047] The shell head 14 has a configuration that surrounds the oscillator assembly 17 and holds the oscillator assembly 17. The shell head 14 has two inner surfaces perpendicular to the Y direction and two inner surfaces perpendicular to the X direction. The two inner surfaces perpendicular to the Y direction each function as a heat input surface.

[0048] Two outer surfaces 22a and 22b of the main backing 22, perpendicular to the Y direction, are joined to two inner surfaces of the shell head 14, perpendicular to the Y direction. Heat is transferred from the main backing 22 to the shell head 14 through the two interfaces created by this joining. Gaps G1 and G2 are created between two outer surfaces 22c and 22d of the main backing 22, perpendicular to the X direction, and two inner surfaces 14c and 14d of the shell head 14, perpendicular to the X direction. Each gap G1 and G2 has a slit-like shape. Gap G1 includes the space located directly below the first protruding portion of the sub-backing 21. Gap G2 includes the space located directly below the second protruding portion of the sub-backing 21.

[0049] The first hanging portion 28 has a first vertical portion 28A as its upper end portion. The first vertical portion 28A passes through the gap G1. A first group of electrical components 66 is provided on the inner surface (main backing side surface) of the first vertical portion 28A. The first group of electrical components 66 consists of multiple electrical components arranged in the Y and Z directions. Specifically, the first group of electrical components 66 includes multiple capacitors necessary for the operation of the electronic circuit 37.

[0050] An electrical insulating plate 74 is provided between the first electrical component group 66 and the outer surface 22c of the main backing 22 as an electrical insulating member. This prevents electrical short circuits between the main backing 22 and the first electrical component group 66. The electrical insulating plate 74 is bonded to the first electrical component group 66 or to the main backing 22.

[0051] A reinforcing plate 68 is bonded to the outer surface (the surface facing the inner surface 14c) of the first vertical portion 28A. The reinforcing plate 68 may be further fixed to the inner surface 14c using double-sided adhesive tape or the like. The reinforcing plate 68 is made of, for example, an insulating material.

[0052] The second hanging portion 30 has a second vertical portion 30A as its upper end. The second vertical portion 30A passes through the gap G2. A second group of electrical components 76 is provided on the inner surface (main backing side surface) of the second vertical portion 30A. The second group of electrical components 76 consists of multiple electrical components arranged in the Y and Z directions. Specifically, the second group of electrical components 76 includes multiple capacitors necessary for the operation of the electronic circuit 37.

[0053] An electrical insulating plate 77 is provided between the second electrical component group 76 and the outer surface 22d of the main backing 22 as an electrical insulating member. This prevents electrical short circuits between the main backing 22 and the second electrical component group 76. The electrical insulating plate 77 is bonded to the second electrical component group 76 or to the main backing 22.

[0054] A reinforcing plate 78 is bonded to the outer surface (the surface facing the inner surface 14d) of the second vertical portion 30A, serving as a reinforcing member. The reinforcing plate 78 may be further fixed to the inner surface 14d using double-sided adhesive tape or the like. The reinforcing plate 78 is made of, for example, an insulating material.

[0055] The upper surface 22e of the main backing 22 is joined to the lower surface of the sub-backing 21. The lower surface 22f of the main backing 22 is an exposed surface. As will be described later, a sound-absorbing member or a heat-conducting member may be provided on the lower surface 22f.

[0056] A temperature sensor 200 is provided on the outer surface 22b, which functions as a heat output surface. Specifically, the temperature sensor 200 is provided on the lower part 22b1 at the center in the X direction of the outer surface 22b. The temperature sensor 200 is composed of, for example, a thermistor. A signal line 202 is drawn out from the temperature sensor 200. The signal line 202 is connected to the FPC 24 or to a signal line in a probe cable (not shown). Multiple temperature sensors may be provided on the outer surface 22b. Temperature sensors may be provided on both the outer surface 22a and the outer surface 22b.

[0057] The placement of the temperature sensor 200 makes it possible to monitor the temperature of the main backing, particularly the temperature of the interface between the main backing and the shell head. This allows for the management of the surface temperature of the ultrasonic probe, especially the surface temperature of the transmitting and receiving wavefronts.

[0058] In this embodiment, gaps G1 and G2 are secured on both sides of the main backing in the X direction. The FPC 24 passes through gaps G1 and G2. The first electrical component group 66 and the second electrical component group 76 are arranged close to the electronic circuit 37 using gaps G1 and G2.

[0059] Figure 5 is a schematic diagram showing the XY cross-section of the tip of the ultrasonic probe. The main backing 22 has two outer surfaces 22a and 22b perpendicular to the Y direction, and two outer surfaces 22c and 22d perpendicular to the X direction. On the other hand, the shell head 14 has two inner surfaces 14a and 14b perpendicular to the Y direction, and two inner surfaces 14c and 14d perpendicular to the X direction.

[0060] The outer surface 22a and the inner surface 14a are joined, and the outer surface 22b and the inner surface 14b are joined. A gap G1 is created between the outer surface 22c and the inner surface 14c. A gap G2 is created between the outer surface 22d and the inner surface 14d. The first vertical portion 28A, the first group of electrical components 66, the electrical insulating plate 74, and the reinforcing plate 68 are arranged in gap G1. The second vertical portion 30A, the second group of electrical components 76, the electrical insulating plate 77, and the reinforcing plate 78 are arranged in gap G2.

[0061] A recess 204 is formed in the shell head 14. The opening of the recess 204 constitutes part of the inner surface 14b. The internal space of the recess 204 functions as a housing chamber for the temperature sensor 200. The wall surface of the recess 204 is separated from the temperature sensor 200. The temperature sensor 200 is in contact only with the outer surface 22b of the main backing 22.

[0062] Generally, processing backings with thermal anisotropy is difficult; that is, it is difficult to form recesses in the main backing 22. Therefore, in this embodiment, a recess 204 is formed in the shell head 14, and a temperature sensor 200 is placed inside it. Since the shell head 14 is not in direct contact with the temperature sensor 200, the temperature sensor 200 can accurately measure the temperature of the heat output surface.

[0063] In this embodiment, each outer surface 22a, 22b, 22, 22d is flat. All or part of each outer surface 22a, 22b, 22, 22d may be curved. Similarly, in this embodiment, each inner surface 14a, 14b, 14c, 14d is flat. All or part of each inner surface 14a, 14b, 14c, 14d may be curved.

[0064] Figure 6 shows the shell 12. As previously described, the shell 12 consists of a shell head 14, a middle section 15, and a rear section 16. The shell head 14 has two inner surfaces perpendicular to the Y direction (only one inner surface 14a is shown in Figure 6), and two inner surfaces 14c and 14d perpendicular to the X direction. Heat from the main backing flows into the shell head 14 through the two inner surfaces perpendicular to the Y direction (see reference numeral 90). This heat diffuses into the shell head 14 (see reference numeral 94) and simultaneously diffuses throughout the entire shell 12 (see reference numerals 92 and 96). The heat diffused in the shell 12 is released to the outside through the resin case and also through the probe cable.

[0065] Figure 7 shows the YZ cross-section of the ultrasonic probe. The direction of heat transfer generated in the electronic circuit 37 and the two-dimensional vibrating element array is indicated by reference numeral 102. The heat moves from the sub-backing 21 to the main backing 22. The movement of heat in the Y direction after it has entered the main backing 22 is indicated by reference numeral 104. This heat then flows into the shell 12. Reference numeral 106 indicates the direction of heat transfer (diffusion direction) within the shell 12.

[0066] Figure 7 shows a probe cable, a signal wire bundle within the probe cable, and multiple connectors connected to the signal wire bundle. The multiple connectors connected to the signal wire bundle are connected to multiple connectors provided on the FPC.

[0067] Figure 8 shows a YZ cross-section of the tip of the ultrasonic probe. As already explained, a recess 204 is formed in the shell head 14. The internal space of the recess 204 is a chamber for housing the temperature sensor 200. The inner surface of the recess 204 is separated from the temperature sensor 200.

[0068] The detection surface 200a of the temperature sensor 200 is bonded to the outer surface 22b of the main backing. Specifically, the bonded position of the temperature sensor 200 is the center in the X direction and the lower end in the Z direction of the outer surface 22b. A signal line 202 is drawn out from the temperature sensor 200. The lower surface of the main backing is also a highly thermally conductive surface. A temperature sensor may be placed on its lower surface.

[0069] Modified examples will be described using Figures 9 and 10. Figure 9 shows the first modified example. A sound-absorbing plate 108 is provided on the underside of the main backing 22. Specifically, the sound-absorbing plate 108 is joined to the underside of the main backing. If the ultrasonic waves are not completely attenuated within the main backing 22, the ultrasonic waves may be reflected from the underside of the main backing 22, and the resulting reflected waves may return to the two-dimensional vibrating element array. Such reflected waves degrade the image quality of the ultrasonic image. By providing a sound-absorbing plate 108 on the underside of the main backing 22, the generation of the above-mentioned reflected waves can be effectively suppressed.

[0070] Figure 10 shows a second modified example. A heat conduction plate 110 is provided on the underside of the main backing 22. Specifically, the heat conduction plate 110 is joined to the underside of the main backing 22. Heat generated in the electronic circuit, etc., moves to the main backing 22 via the sub-backing 21, as indicated by arrow 112. The heat that flows into the main backing 22 moves directly from the main backing 22 to the shell 12, as indicated by arrow 114, and also moves from the main backing 22 to the shell 12 via the heat conduction plate 110, as indicated by arrow 116. The underside of the main backing 22 is also a highly heat-conductive surface. Therefore, according to the second modified example, the efficiency of heat conduction from the main backing 22 to the shell 12 can be further increased.

[0071] According to the embodiment described above, heat generated in electronic circuits, etc., can be guided to the heat absorbing member via a path with extremely high thermal conductivity within the backing member. This effectively suppresses the temperature of the transmitting and receiving wavefronts that come into contact with living tissue. Furthermore, since two gaps can be secured near the main backing, wiring members can be placed using these gaps, and groups of electrical components can also be placed using these gaps. Since both sides in contact with the two gaps are low thermal conductivity surfaces, the groups of electrical components can be thermally protected. Moreover, since a sub-backing is provided above the main backing and their orientations are orthogonal, heat can be diffused in the X direction in the sub-backing and then guided in the Y direction in the main backing. In addition, since a temperature sensor is placed on the high thermal conductivity surface of the main backing and the temperature sensor is separated from the shell, the temperature of the main backing can be accurately detected, that is, the heat transport function of the main backing can be accurately measured.

[0072] In the above embodiment, the secondary backing may be omitted. In that case, the electronic circuit is provided on the upper surface of the main backing. Also, in the above embodiment, the backing member may be composed of three or more backings. If the laminate has a cylindrical surface shape, the upper surface of the backing member is also cylindrical. Other backings besides those described above may be used as thermally anisotropic backings. For example, a backing in which multiple thermal conductive layers and multiple spacers are alternately laminated may be used. [Explanation of symbols]

[0073] 10 Ultrasonic probe, 11 Resin case, 12 Shell, 14 Shell head, 20 Backing material, 21 Sub-backing, 22 Main backing, 24 FPC, 36 Laminate, 37 Electronic circuit, 66 First electrical component group, 76 Second electrical component group, 200 Temperature sensor.

Claims

1. A vibrating button array, An electronic circuit provided on the rear side of the vibrating element array and electrically connected to the vibrating element array, A backing is provided on the rear side of the aforementioned electronic circuit to attenuate ultrasonic waves from the vibrating element array, Includes, When the arrangement direction of the vibration element array, the electronic circuit, and the backing is defined as the Z direction, the direction perpendicular to the Z direction is defined as the X direction, and the direction perpendicular to both the Z and X directions is defined as the Y direction, In the aforementioned backing, the thermal conductivity in the Z direction and the thermal conductivity in the Y direction are both greater than the thermal conductivity in the X direction. The backing has two outer surfaces intersecting in the X direction and two outer surfaces intersecting in the Y direction, The two outer surfaces intersecting in the X direction are each low-thermal-conductivity surfaces having a lower thermal conductivity than the two outer surfaces intersecting in the Y direction. The two outer surfaces intersecting in the Y direction are, each, high thermal conductivity surfaces having a higher thermal conductivity than the two outer surfaces intersecting in the X direction. A temperature sensor is positioned on at least one of the two outer surfaces that intersect in the Y direction. A heat-absorbing member is provided, having two inner surfaces joined to the two outer surfaces perpendicular to the Y direction. The heat-absorbing member includes a recess having a housing space for housing the temperature sensor, The temperature sensor is separated from the inner surface of the recess. An ultrasonic probe characterized by the following features.

2. In the ultrasonic probe according to claim 1, The outer surface on which the temperature sensor is located has an upper end close to the electronic circuit and a lower end farther from the electronic circuit. The temperature sensor is located at the lower end. An ultrasonic probe characterized by the following features.

3. A vibrating element array, An electronic circuit provided on the rear side of the vibrating element array and electrically connected to the vibrating element array, A backing is provided on the rear side of the aforementioned electronic circuit to attenuate ultrasonic waves from the vibrating element array, Includes, When the arrangement direction of the vibration element array, the electronic circuit, and the backing is defined as the Z direction, the direction perpendicular to the Z direction is defined as the X direction, and the direction perpendicular to both the Z and X directions is defined as the Y direction, In the aforementioned backing, the thermal conductivity in the Z direction and the thermal conductivity in the Y direction are both greater than the thermal conductivity in the X direction. The backing has two outer surfaces that intersect in the Y direction, A temperature sensor is positioned on at least one of the two outer surfaces that intersect in the Y direction. The aforementioned backing is the main backing, A sub-backing is provided between the electronic circuit and the main backing. In the aforementioned sub-backing, the thermal conductivity in the Z direction and the thermal conductivity in the X direction are both greater than the thermal conductivity in the Y direction. The heat diffused in the X direction within the sub-backing is transferred to the heat-absorbing member via the main backing. The temperature sensor detects the temperature of the interface between the main backing and the heat-absorbing member. An ultrasonic probe characterized by the following features.

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