JP6700916B2 - Acoustic wave probe and information acquisition device - Google Patents

Description

  The present invention relates to an acoustic wave probe that transmits and receives acoustic waves such as ultrasonic waves (when transmitting and receiving in this specification means at least one of transmission and reception), an information acquisition device using the same, and the like. In this specification, an acoustic wave includes an elastic wave called a photoacoustic wave, an optical ultrasonic wave, a sound wave, an ultrasonic wave, or the like, and an acoustic wave generated by light irradiation may be particularly called a “photoacoustic wave”. .. Further, among the acoustic waves, the acoustic wave transmitted from the probe may be referred to as “ultrasonic wave”, and the acoustic wave reflected from the inside of the subject may be particularly referred to as “reflected wave”. In some cases, an ultrasonic wave is referred to as an ultrasonic wave.

  Generates an image of the inside of the subject using a technique called ultrasonic imaging that acquires information about the inside of the subject by transmitting ultrasonic waves to the subject and receiving the ultrasonic waves reflected from the inside of the subject. There is a way to do it. An array-shaped ultrasonic transducer is used as a device for transmitting and receiving this ultrasonic wave (see Patent Document 1). Further, as one of the optical imaging techniques, there is a technique called Photoacoustic Imaging (PAI: Photoacoustic Imaging). Photoacoustic imaging is a technique of receiving a photoacoustic wave generated by irradiation of light and generating image data from a received signal obtained. This photoacoustic wave is generated by irradiating a subject such as a living body with pulsed light from a light source and expanding a tissue that has absorbed the energy of light propagating in the subject.

US Patent Publication No. 2007/0287912

  In a conventional ultrasonic transducer, the positional relationship of array-shaped elements is usually fixed. Therefore, the probe is used by pressing it against the surface of the subject, deforming the surface of the subject according to the surface shape of the probe, and bringing the probe into close contact with the subject. However, in this configuration, since the surface of the subject is deformed and brought into close contact with the probe, it may be difficult to sufficiently bring the probe into close contact with the subject having a curvature when trying to make close contact with a wide area.

  In view of the above problems, the acoustic wave probe according to one aspect of the present invention has a plurality of acoustic wave transducers and a wiring that electrically connects between the plurality of acoustic wave transducers, and in each region, An interval between the plurality of acoustic wave transducers adjacent to each other in the expansion/contraction direction is expandable/contractible, and the wiring is arranged so as to extend in a direction intersecting with the expansion/contraction direction.

  ADVANTAGE OF THE INVENTION According to this invention, the acoustic wave probe which can fully adhere|attach even the comparatively wide part which has a curvature of a test object can be provided. Therefore, when this is used in the information acquisition device, the object information can be acquired stably and accurately.

It is a top view explaining the acoustic wave probe which concerns on 1st Embodiment. It is sectional drawing explaining the acoustic wave probe which concerns on 1st Embodiment. It is a figure explaining the acoustic wave probe which concerns on 1st Embodiment. It is a perspective view explaining the acoustic wave probe which concerns on 1st Embodiment. It is sectional drawing explaining the acoustic wave probe which concerns on 1st Embodiment. It is sectional drawing explaining the acoustic wave probe which concerns on 2nd Embodiment. It is a top view explaining the acoustic wave probe which concerns on 3rd Embodiment. It is sectional drawing explaining the acoustic wave probe which concerns on 3rd Embodiment. It is a top view explaining the acoustic wave probe which concerns on 3rd Embodiment. It is sectional drawing explaining the acoustic wave probe which concerns on 3rd Embodiment. It is a perspective view explaining the acoustic wave probe concerning a 4th embodiment. It is a perspective view explaining the acoustic wave probe concerning a 5th embodiment. It is a perspective view explaining the acoustic wave probe concerning a 5th embodiment. It is sectional drawing explaining the acoustic wave probe which concerns on 5th Embodiment. It is a perspective view explaining the acoustic wave probe concerning a 6th embodiment. It is sectional drawing explaining the acoustic wave probe which concerns on 6th Embodiment. It is a perspective view explaining the acoustic wave probe which concerns on 7th Embodiment. It is a top view explaining the acoustic wave probe which concerns on 7th Embodiment. It is a top view explaining the acoustic wave probe which concerns on 7th Embodiment. It is a figure explaining the acoustic wave probe which concerns on 8th Embodiment. It is a circuit diagram explaining the acoustic wave probe which concerns on 8th Embodiment. It is a figure explaining the acoustic wave probe which concerns on 8th Embodiment. It is a figure explaining the acoustic wave probe which concerns on 8th Embodiment. It is a figure explaining the information acquisition apparatus which concerns on 9th Embodiment. It is a figure explaining the information acquisition apparatus which concerns on 10th Embodiment.

  In one aspect of the present invention, in solving the above problems, when a probe is attached to a subject, a stretching direction in which the intervals of a plurality of acoustic wave transducers are changed, and wiring for arranging wiring for connecting the acoustic wave transducer and the outside The directions were separated structures. That is, the wiring extending in the expansion/contraction direction does not exist. The former direction is, for example, a direction in which the spacing between adjacent acoustic wave transducers arranged on a holding film, which is a support member, expands and contracts, and the latter direction is a direction in which a wiring connecting the acoustic wave transducer and the outside extends. The separated structure is a structure that intersects with each other instead of parallel (for example, substantially orthogonal structure). With such a structure, the probe can be used, for example, to enclose a measurement object having a truncated cone (shape having a thickness different depending on a place) such as an arm (see FIG. 2-1). For example, as shown in FIG. 1-3, in each region along the direction in which the thickness of the measurement target changes, the spacing between the acoustic wave transducers adjacent to each other in the expansion/contraction direction can be flexibly expanded/contracted, so that the wiring does not expand/contract It can conform to the surface shape of the measurement target.

Embodiments of the present invention will be described below with reference to the drawings. However, the present invention is not limited to these embodiments, and various modifications and changes can be made within the scope of the invention.
(First embodiment)
The present embodiment is characterized in that the member connecting the acoustic wave transducers flexibly expands and contracts in the expansion and contraction direction substantially orthogonal to the direction of the wirings in which the wirings connecting the acoustic wave transducers are arranged.

  This embodiment will be described with reference to FIGS. 1-1 to 2-2. In the figure, 100 is an acoustic wave probe, 101 is an acoustic wave transducer, 102 is wiring, 103 is a spring structure or spring member, and 104 is a stretchable support member. In these figures showing a schematic view of the acoustic wave probe 100 of the present embodiment, FIG. 1-1 is an overall overhead view, and FIG. 1-2(a) is a plane perpendicular to the X direction in FIG. 1-1. 1-2 is a cross-sectional view of a plane perpendicular to the Y direction in FIG.

  In the acoustic wave probe 100 of this embodiment, the acoustic wave transducers 101 are arranged in a two-dimensional array. The wiring 102 is arranged so as to extend along the plurality of acoustic wave transducers 101 arranged in a line in the wiring direction X. The output signals of the acoustic wave transducers 101 are drawn out in parallel to the outside of the probe 100 for each column in the wiring direction X by the wiring 102. The acoustic wave transducer 101 and the wiring 102 are supported by a holding film 104 that is a supporting member. The holding film 104 can be used as long as it can support the acoustic wave transducer 101 and the wiring 102 and at least expands and contracts in the expansion and contraction direction. Specifically, it can be made of resin, rubber, metal or the like. A plurality of spring structures 103 that expand and contract in the expansion and contraction direction Y are arranged and connected in parallel between the acoustic wave transducers 101. The spring structure 103 can be used as long as it can expand and contract according to an external force. Specifically, a coil-shaped member made of metal, resin, rubber, or the like, or a string-shaped member can be used. If the holding film 104 itself expands and contracts according to an external force, it is not necessary to separately provide a special spring structure as in the second embodiment of FIG. As described above, in the present embodiment, a plurality of acoustic wave transducers are two-dimensionally arranged, and in each region, the spacing between adjacent acoustic wave transducers in the expansion/contraction direction can be expanded/contracted, and the wiring is substantially orthogonal to the expansion/contraction direction. It extends in the direction of the wiring. In all areas, the expansion/contraction direction of each area and the wiring direction are substantially parallel to each other.

  By using the structure described above, the probe 100 of the present embodiment does not expand or contract much in the wiring direction X in which the wiring 102 is arranged, but expands or contracts in the expansion/contraction direction Y substantially orthogonal to the wiring direction X. it can. Therefore, by applying an external force, the distance in the Y direction between the wirings 102 arranged in parallel to the wiring direction X can be changed depending on the location. Thus, as shown in FIG. 1C, the wirings 102 are changed to a non-parallel state (that is, a state in which the extending directions of the plurality of wirings have intersections or angles).

  For example, the body part (arm, leg, finger, etc.) that is the subject does not have a uniform curvature, but has a shape in which the curvature changes depending on the place, in other words, a shape that combines parts close to a truncated cone. There is. Therefore, when a conventional acoustic wave probe in which the positional relationship of a plurality of elements (acoustic wave transducers) is fixed, only limited plane or curved surface information from one certain direction can be acquired. On the other hand, by disposing the probe 100 of the present embodiment so that the direction in which the subject 99 has a curvature and the expansion/contraction direction Y are substantially parallel to each other, the spring structure 103 or the holding structure 103 is held according to the magnitude of the curvature. The membrane 104 expands and contracts. Therefore, as shown in FIG. 2A, the surface shape of the probe 100 can be freely changed along the curvature of the subject.

  Further, according to the present embodiment, the surface shape of the probe 100 can be changed without being restricted by the lead-out wiring to the outside, so that the acoustic wave transducer can be reliably provided over a wide region having the curvature of the subject 99. Can be closely attached. Therefore, the subject information can be stably acquired from a wide region having a curvature of the subject 99. Further, according to the present embodiment, the subject information can be acquired from the outer circumference of the tubular subject such as the arm, leg, or finger.

  Here, consider a configuration in which the external lead wires from the plurality of acoustic wave transducers 101 are not arranged on the holding film 104, but the wires hang down from the respective acoustic wave transducers 101. In this configuration, the acoustic wave transducer 101 may be pulled by the weight of the wiring or something touching the tip of the wiring, and the acoustic wave transducer 101 may come off without being brought into close contact with the subject. .. On the other hand, in the configuration of the present embodiment, since the wirings 102 are bundled and arranged on the holding film 104, the wirings can be integrated by an FPC (flexible substrate) or the like, and the wiring itself can be light and have a simple configuration. Further, since the wiring 102 is arranged on the holding film 104, it is possible to prevent the wiring from coming into contact with another member or the like and being pulled. From these facts, the present embodiment can obtain an effect that cannot be obtained by the configuration in which the external lead wires from the plurality of acoustic wave transducers 101 are not arranged in the holding film 104 and are hung from the respective acoustic wave transducers 101. .

  Furthermore, consider a configuration in which the spring structure 103 is not used and the entire structure is arranged on a holding film 104 that does not expand or contract. With this configuration, the above-described problem in the hanging configuration is solved, but since the interval between the wirings 102 cannot be changed, when an attempt is made to make close contact with an object having a different curvature, the remaining portion of the holding film 104 with respect to the object is left. May come out and twist or the like may occur. Therefore, due to this twist, there may be a portion where the acoustic wave transducer 101 and the subject are not in close contact with each other. According to the configuration of the present embodiment, the spacing of the wirings 102 can be flexibly changed according to the surface shape of the subject, so that the occurrence of this twist can be suppressed. In this way, the acoustic wave transducer 101 can be reliably brought into close contact with a wide area of the subject having a curvature.

  Although the wiring 102 (that is, the acoustic wave transducer 101) has a configuration in which the angle of the expanding and contracting direction Y with respect to the direction X of the wiring in which the wirings 102 (that is, the acoustic wave transducers 101) are aligned is substantially vertical in FIG. 1-1, the present invention is not limited to this. This angle can be selected as an optimum angle according to the subject to be measured and is preferably set between 45 degrees and 135 degrees.

  Further, at the time of acquiring the object information, it is desirable to dispose an ultrasonic gel 120 that transmits ultrasonic waves between the acoustic wave transducer 101 and the object 99, as shown in FIG. As a result, the gas layer that shields the ultrasonic waves can be excluded from between the flat surface of each acoustic wave transducer 101 and the surface of the subject 99, and the space can be filled with the ultrasonic gel 120. Therefore, the ultrasonic wave 131 from the acoustic wave transducer 101 and the ultrasonic wave 132 from the subject 99 can be efficiently and stably transmitted and received between the transducer and the subject, and more stable and accurate information from the subject can be obtained. be able to.

  Further, on the surface of the acoustic wave transducer 101 of the present embodiment, as shown in FIG. 2B, a flexible member 121 having acoustic transparency can be arranged. Thereby, the flat surface of each acoustic wave transducer 101 and the surface of the subject 99 facing each other can be more reliably brought into close contact without using the ultrasonic gel 120.

  Further, the flexible member 121 having the structure shown in FIG. 2B may be subjected to a treatment for imparting adhesiveness to the surface thereof to form a structure having an adhesive layer. This allows the acoustic wave transducer 101 to be attached to the surface of the subject and temporarily fixed, so that the mechanism for closely contacting and holding the acoustic wave transducer 101 on the subject can be simplified. In addition, since it can be temporarily and reliably fixed, the subject information can be acquired more stably and accurately. As the adhesive layer, any material can be used as long as it can impart adhesiveness to the surface of the flexible member 121 and can adhere the flexible member 121 to a subject or peel it from the subject. For example, it can be realized by a configuration in which an adhesive is arranged on the surface of the flexible member 121. Specifically, as the adhesive, a rubber adhesive, an acrylic adhesive, a silicone adhesive, a urethane adhesive, or the like can be used. The optimum material may be selected according to the required adhesive strength and peelability.

  A thin resin sheet, rubber, or the like can be used for the flexible member 121 described above. An elastomer, which is an elastic rubber, is particularly preferable because it has a large elasticity, is deformed along the surface shape of the subject 99, and easily adheres to the subject 99. Further, since the flexible member 121 can be peeled off while being deformed when peeled from the subject, the flexible member 121 can be peeled off without applying a large load to the subject. As the physical properties of the flexible member, it is desirable that the ultrasonic permeability is high and the acoustic impedance is close to that of the subject, but a flexible member having necessary characteristics can be selected according to individual use conditions.

(Second embodiment)
The second embodiment relates to the configuration of a spring structure that expands and contracts. Other than that, it is the same as the first embodiment. The second embodiment will be described with reference to FIG.

  In the present embodiment, the support member that supports the acoustic wave transducer 101 and the wiring 102 and the spring structure 103 are configured by the same film-shaped holding film 104. The film-shaped holding film 104 of the present embodiment is made of a stretchable member and has the same functions and effects as the spring structure 103 of FIG. As a result, even in a configuration in which the spring structure 103 is not provided separately, the same effect as that of the first embodiment can be obtained. The holding film 104 of the present embodiment, which also serves as the spring structure 103, can be easily configured by a stretchable sheet-shaped member such as silicone rubber.

  According to the present embodiment, it is possible to provide an acoustic wave probe with a simple configuration, which can be surely brought into close contact with a wide region having a curvature of the subject, and can obtain subject information stably and accurately.

(Third Embodiment)
The third embodiment relates to the structure of a spring structure that expands and contracts. Other than that, it is the same as the second embodiment. A third embodiment will be described with reference to FIGS. 4-1 to 4-4. In the figure, 105 is a groove and 106 is a through hole.

  The present embodiment is characterized in that the holding film 104 has regions having different thicknesses between the rows of the acoustic wave transducers 101 arranged in the wiring direction X. Specifically, the groove 105 extending in the wiring direction X is provided between the rows of the acoustic wave transducers 101 arranged in the wiring direction X. FIG. 4A is a schematic view of the acoustic wave probe according to the present embodiment, FIG. 4-2(a) is a schematic view of the AA′ cross section in FIG. 4A, and FIG. FIG. 4 shows a schematic view of a BB′ cross section at 4-1.

  In the present embodiment, since the thin region of the holding film 104 is arranged between the rows formed by the acoustic wave transducers 101 arranged in the wiring direction X, the holding film 104 is arranged between the rows of the acoustic wave transducers 101. It is easy to expand and contract, so it is easy to change the distance. On the other hand, in the direction in which the acoustic wave transducers 101 are arranged in the wiring direction X, the thickness of the holding film 104 is large and it is difficult to expand and contract, so that the wiring 102 on the holding film 104 is loaded and damaged. Can be avoided.

  As described above, according to the present embodiment, the wiring of the acoustic wave transducer is highly reliable, and it is possible to reliably adhere to a wide area having a curvature of the subject and to obtain the subject information stably and accurately. An acoustic wave probe can be provided.

  Another mode of the present embodiment will be described with reference to FIGS. 4-3 and 4-4. Fig. 4-3 is a schematic view of the acoustic wave probe of this another embodiment, Fig. 4-4(a) is a schematic diagram of the CC' cross section in Fig. 4-3, and Fig. 4-4(b) is a diagram. 4D is a schematic view of a DD′ cross section taken along line 4-3. FIG. In this another mode, the holding film 104 has the through holes 106 between the rows formed by the acoustic wave transducers 101 arranged in the wiring direction X. By appropriately setting the size, number, shape, and position of the holes 106 between the rows formed by the acoustic wave transducers 101, the elasticity of the holding film 104 between the rows of the acoustic wave transducers 101 can be set to a desired value. Can be Further, since it suffices to form the hole 106 in the holding film 104, the manufacturing process can be made simpler and the necessary stretchability can be controlled more accurately as compared with the form of FIG. 4-1. Therefore, the acoustic wave transducer 101 can be more closely attached to the surface of the subject.

  Further, as compared with the configuration in which the upper limit of the depth of the groove 105 in FIG. 4A is restricted, the stretchability can be adjusted by the ratio of the holes or the like, so that the thickness of the holding film 104 can be increased. As a result, the holding film 104 can have higher strength for holding the wiring 102 of the acoustic wave transducer 101, the load applied to the wiring 102 during use can be reduced, and the reduction in reliability can be reduced. it can. Also according to this another mode, an acoustic wave probe that has high reliability of the wiring of the acoustic wave transducer, is more closely attached to a wide area having a curvature of the subject, and can obtain the subject information stably and accurately. Can be provided.

(Fourth Embodiment)
The fourth embodiment relates to a method of fixing the acoustic wave probe 100 to a subject. Other than that, it is the same as any of the first to third embodiments. The fourth embodiment will be described with reference to FIG. In FIG. 5, 110 is a fixing member. The present embodiment is characterized in that it has a mechanism (fixing member) 110 for winding and fixing the acoustic wave probe 100 around a cylindrical portion of the subject 99.

  When acquiring information from the subject 99, as shown in FIG. 5, the holding film 104 is wrapped around the subject 99 and fixed by the fixing means 110, so that the holding film 104 including the acoustic wave transducer 101 is obtained. Is pressed against the subject 99 and brought into close contact therewith. As a result, information on the inside of the subject can be acquired from any direction on the outer circumference of the subject 99. Therefore, the subject information can be acquired not only from a specific surface of the subject 99 but also from more directions, and by using this probe, a more detailed subject image can be reproduced. Although no medium is arranged between the acoustic wave transducer 101 and the subject 99 in FIG. 5, as shown in FIGS. 2-2(a) and 2-2(b), the ultrasonic gel 120 and A configuration may be used in which the flexible member 121 having acoustic transparency is used. This point is the same in the embodiments described later.

  According to the present embodiment, it is possible to provide an acoustic wave probe capable of reliably adhering to a wide area having a curvature of the subject and stably acquiring more detailed subject information.

(Fifth Embodiment)
The fifth embodiment relates to a method of fixing the acoustic wave probe 100 to a subject. Other than that, it is the same as any of the first to third embodiments. The fifth embodiment will be described with reference to FIGS. 6-1 to 6-3. In the figure, 111 is a support member having a recess.

  The support member 111, which is flexible and somewhat rigid, has a half-moon shaped recess (groove), and the holding film 104 is arranged so as to cover the recess of the support member 111. Held in. The holding film 104 is held from the left and right by the support member 111, and the holding film 104 itself is in a tensioned state (tensioned state). In this state, as shown in FIG. 6B, by pressing the support member 111 against the subject 99 side, the holding film 104 is deformed along the surface shape of the subject 99. As a result, as shown in the schematic cross-sectional view of FIG. 6C, the acoustic wave transducers 101 on the holding film 104 are arranged at positions along the surface shape of the subject 99. Since the supporting member 111 is used in the configuration of FIG. 6C, the tension applied to the holding film 104 on the film is uniform. Therefore, after that, only by controlling the force with which the support member 111 is pressed against the subject 99, the entire holding film 104 can be pressed against the subject 99 side in a stable state even with a holding film having a large area.

  According to the present embodiment, it is possible to provide an acoustic wave probe capable of reliably adhering to a wider region having a curvature of the subject and stably obtaining more detailed subject information.

(Sixth Embodiment)
The sixth embodiment relates to a method of fixing the acoustic wave probe 100 to a subject. A sixth embodiment, which is otherwise the same as the fifth embodiment, will be described with reference to FIGS. 7-1 and 7-2. In the figure, 112 is a lid, 113 is a hinge part, 114 is a bag (supporting means) filled with gas, and 115 is a bag (supporting means) filled with gas.

  In the present embodiment, as shown in FIG. 7A, a lid 112 having substantially the same shape as the support member 111 of the acoustic wave probe is provided, and the lid 112 has a part of the support member 111 via a hinge portion 113. It is characterized by being fixed. In addition, a bag 114 that can expand and contract by injecting gas is provided in the concave portion of the lid 112. On the other hand, the gas-filled bag 115 has a tubular shape and is arranged at the bottom of the recess of the support member 111, which is the space between the support member and the holding film.

  As shown in FIG. 7B, when the lid 112 is closed, the subject 99 is pushed by the bag 114 on the upper side, while it is pushed by the bag 115 from the lower side via the holding film 104. Since the bags 114 and 115 are filled with a gas, when the subject 99 is pushed to a certain degree (when the bag 115 is deformed to some extent), the bags 114 and 115 push back the subject 99 and press it. When balanced, the subject 99 holds its position. The amount of gas injected into the expandable bags 114 and 115 is adjusted while monitoring the internal pressure so that the subject 99 is fixed so as not to move and the subject 99 does not feel uncomfortable pain. It should be set optimally.

  In the configuration of the present embodiment, the acoustic wave transducer 101 can be placed along the surface shape of the subject 99. Further, since the load applied to the subject 99 can be reduced and the movement of the subject can be suppressed to the minimum, the subject 99 and the plurality of acoustic wave transducers 101 can be acquired at the time of obtaining the subject information. It is possible to reduce the deviation of the positional relationship of Further, by using the bags 114 and 115, it is possible to flexibly deal with the subject 99 having various surface shapes, it becomes unnecessary to select the shape of the subject, and the acoustic wave that can stably hold the position of the subject. A probe can be realized.

  According to this embodiment, it is possible to provide an acoustic wave probe capable of reliably adhering to a wide area having a curvature of the subject, stably holding the subject, and stably acquiring more detailed subject information. .. According to the present embodiment, since the positional relationship between the subject and the acoustic wave transducer can be easily and stably fixed when acquiring the subject information, it corresponds to various target parts of the subject and is efficiently and of high quality. An acoustic wave probe capable of receiving an acoustic wave can be provided.

(Seventh embodiment)
An acoustic wave probe according to the seventh embodiment will be described with reference to FIGS. 8-1 to 8-3. The seventh embodiment is characterized in that the concave shape of the support member 116 is a hemispherical concave portion, and is otherwise the same as the fifth embodiment.

  In the present embodiment, the support member 116 holding the holding film 104 has a hemispherical recess, and the holding film 104 having the acoustic wave transducer 101 is arranged so as to cover the recess. The pattern of the wiring 102 connecting the acoustic wave transducers 101 can be arranged in a spiral shape as shown in FIG. 8-2, for example. In the present embodiment, in each region, the spacing between the acoustic wave transducers adjacent to each other in the expansion/contraction direction can be expanded/contracted, and the wiring extends in the direction of the wiring intersecting with the expansion/contraction direction. There are multiple areas whose directions are non-parallel.

  In this embodiment, since the concave shape of the support member 116 is hemispherical, the holding film 104 can cover the subject so as to wrap it in more directions than in the first embodiment. Therefore, the convex portion of the subject 99 can be pressed against the holding film 104 to acquire the subject information. For example, it is particularly suitable for acquiring subject information of a site such as a hand, foot, elbow, knee, or breast.

  In the present embodiment, the arrangement of the wiring 102 is described as a spiral shape, but the arrangement is not limited to this. As shown in FIG. 8C, a configuration including a portion in which the wiring 102 is arranged radially from the center can be similarly used. Here, since the central portion of the holding film 104 and the region between the wirings extend, the wiring 102 does not expand or contract. Again, in each region, the spacing of the acoustic wave transducers can be expanded and contracted, the wiring extends in the wiring direction, and in all regions, the expansion and contraction direction and the wiring direction are non-parallel. Exists. In the present embodiment, the concave shape of the support member 116 of the support member 116 is described as a hemispherical shape, but the present invention is not limited to this. In addition to a support member having a rectangular parallelepiped concave shape, a support member having a polygonal pyramid, a truncated pyramid, an elliptic hemisphere, or the like can be similarly used.

(Eighth Embodiment)
The eighth embodiment relates to the acoustic wave transducer 101. The other points are the same as those of the first to seventh embodiments. FIG. 9-1 is a schematic diagram illustrating the acoustic wave transducer 101 according to the eighth embodiment. In FIG. 9-1(a), 199 is a chip (substrate), 201 is a vibrating film, 202 is a first electrode (upper electrode), 203 is a second electrode (lower electrode), 204 is a support portion, and 205 is It is a cavity. Further, 301 is a first wiring, 302 is a second wiring, 401 is a DC voltage generating means, and 402 is a drive receiving circuit. The transducer 200 in FIG. 9 is the transducer 101 in FIG. 1 or the like, and a plurality of chips (substrates) 199 in FIG. 9 are provided on the holding film 104 in FIG. 1 or the like.

  The present embodiment is characterized in that the acoustic wave transducer 101 is the capacitance type transducer 200. The capacitance transducer 200 is manufactured on a silicon chip 199 by using a MEMS (Micro Electro Mechanical Systems) process to which a semiconductor process is applied. The capacitive ultrasonic transducer has a characteristic that the frequency characteristic of the reception characteristic is significantly superior to that of the piezoelectric ultrasonic transducer.

  The vibrating membrane 201 is supported on the chip 199 by the supporting portion 204, and is configured to vibrate by receiving an acoustic wave (ultrasonic wave). The first electrode 202 is arranged on the vibrating membrane 201, and the second electrode 203 is arranged at a position on the chip 199 facing the first electrode 202. A set of the second electrode 203 and the first electrode 202, which face the vibrating membrane 201 with a gap 205 therebetween, is referred to as a cell. The first electrode 202 is drawn out of the chip 199 via the first wiring 301 and connected to the DC voltage generating means 401. Due to the DC voltage generating means 401, a potential difference of several tens to several hundreds of volts is generated between the first electrode 202 and the second electrode 203.

  The second electrode 203 is drawn out of the chip 199 via the second wiring 302 and connected to the drive receiving circuit 402. A pulse voltage is applied from the drive receiving circuit 402 to the second electrode 203 to generate a change in electrostatic attractive force between both electrodes, whereby the vibrating membrane 201 vibrates and ultrasonic waves are transmitted. The transmitted ultrasonic waves are applied to the subject 99, reflected inside the subject 99, and returned to the vibrating membrane 201.

  When the vibration film 201 and the first electrode 202 vibrate in response to ultrasonic waves, the distance between the first electrode 201 and the second electrode 203 changes, and the capacitance between both electrodes changes. Since there is a potential difference between both electrodes, a minute current is generated corresponding to the change in capacitance. The minute current is converted from a current into a voltage by the drive reception circuit 402 connected to the second electrode 203 and output from the third wiring 303.

  A plurality of cells are arranged on the chip 199, the first electrodes 202 on the chip 199 are electrically connected to each other, and the second electrodes 203 on the chip 199 are electrically connected to each other. All the second electrodes on the chip 199 are connected to different drive receiving circuits 402 for each chip 199. The acoustic wave probe of the present embodiment is provided with the same number of drive receiving circuits 402 as the chips 199, and the plurality of capacitance type transducers 200 have independent sound receiving elements (sound receiving element units are provided for each chip 199). (Also referred to as an element). The size of the sound receiving element is several hundreds of micrometers to several millimeters, and the number of the sound receiving elements is one hundred to several thousands.

  In this embodiment, since the capacitive transducer 200 is used as the acoustic wave transducer 101, the size of the transducer can be reduced and the weight can be reduced. Therefore, when it is placed on the holding film 104, it is easier to be placed along the surface shape of the subject 99. Further, the capacitance type transducer 200 has a wide range of ultrasonic transmission/reception frequencies, and can acquire an acquisition signal including more information from the subject. In this way, it is possible to provide an acoustic wave probe with better reproducibility of the object information.

  The drive reception circuit 402 will be described in detail with reference to FIG. By including the drive reception circuit 402, it is possible to irradiate (transmit) ultrasonic waves from the CMUT 200 toward the subject and detect the ultrasonic waves received by the CMUT 200 as a signal with only one transmission/reception line. In FIG. 9-1(b), 421 is a drive detection circuit (drive receiving circuit), 431 is an operational amplifier, 432 is a feedback resistor, 433 is a feedback capacitor, 434 and 435 are high withstand voltage switches, 436 and 437 are diodes, and 438 is It is a high voltage diode.

  One element (element) or more of the electrostatic transducer 200 is arranged on one chip, and the second electrode 203 of the electrostatic transducer 200 is connected to the drive detection circuit 421. The drive detection circuit 421 has a function of applying a high voltage pulse used for ultrasonic wave transmission from the device side to the CMUT 200, and outputting a minute current from the CMUT 200 as a detection signal to the device side.

  A feedback resistor 432 and a feedback capacitor 433 are arranged in parallel in the negative feedback section of the operational amplifier 431, and have a function of performing current-voltage conversion. High voltage switches 434 and 435 and diodes 436 and 437 are connected to the input terminal and the output terminal of the operational amplifier, respectively. When the voltage between the terminals of the high breakdown voltage diode 438 is a predetermined voltage (less than 1 volt) or less, the wiring connection between the terminals is disconnected. Further, when a voltage higher than a predetermined voltage (about several volts) is applied to the high voltage switches 434 and 435, the wiring between the input and output terminals of the switch is disconnected.

  When the high voltage pulse for transmission is not applied, the high breakdown voltage diode 438 has almost no potential difference between the terminals, and thus the wiring between the input and output terminals is in a disconnected state. On the other hand, since the high voltage switches 434 and 435 are not applied with a high voltage from the outside, the wiring between the switches is connected. Therefore, the minute current from the transducer can be converted into a current voltage by the operational amplifier 431, and the detection signal can be output to a device (not shown) connected to the outside.

  On the other hand, when a high-voltage pulse for transmission is applied from the device (not shown) side, the wiring inside the high-voltage diode 438 is connected, and the high-voltage switches 434 and 435 have a predetermined voltage (about several volts). Higher voltage is applied. Therefore, the high breakdown voltage switches 434 and 435 cut the wiring inside the switches. In this way, it is possible to prevent the operational amplifier 431 from being damaged by being applied with a high voltage. Since the signal output from the operational amplifier is cut by the high voltage switch 435, it does not affect the high voltage pulse applied for transmission. Therefore, a high voltage pulse for transmitting ultrasonic waves can be applied to the second electrode 203 of the transducer.

  As another embodiment of the present embodiment, as shown in FIG. 9B, a configuration in which only the reception circuit is provided instead of the drive detection circuit 421 can be adopted. A transimpedance circuit configuration using an operational amplifier 410 is used for the receiving circuit. A resistor 406 and a capacitor 408 are arranged in parallel in the negative feedback section of the operational amplifier 410, and the current input in the feedback section is converted into a voltage. A resistor 407 and a capacitor 409 are arranged in parallel at the non-inverting input terminal of the operational amplifier 410. Since the operational amplifier 410 has a feedback characteristic, it is possible to reduce the influence of the parasitic capacitance of the input wiring on the current-voltage conversion efficiency by using a wide-band operational amplifier. Therefore, compared with the case where the receiving circuit is arranged in the immediate vicinity of the capacitance type transducer 200 (when the parasitic capacitance of the wiring is extremely small), the current-voltage conversion is less deteriorated and excellent ultrasonic wave reception characteristics can be obtained. it can.

  According to this another aspect, since the transimpedance circuit configuration using the operational amplifier is used for the detection circuit, it is unlikely to be affected by the capacitance parasitic on the input terminal of the detection circuit. Therefore, when the holding film 104 is deformed, the position of the wiring 302 connected to the detection circuit changes. However, since the transimpedance circuit using the operational amplifier is used as described above, the parasitic capacitance of the wiring 302 accompanying it is changed. The reception characteristics are less likely to be affected by changes in the size of the. In this way, it is possible to provide a reception-only probe with little deterioration in reception characteristics.

  As another form of the present embodiment, as shown in FIG. 9C, a wiring 102 for connecting the acoustic wave transducer 101 is provided with a power supply line and a bias line for an amplifier in addition to a wiring for taking out a transmission/reception signal. It is possible to adopt a configuration that has. Since the drive receiving circuit 402 of the ultrasonic transducer includes an operational amplifier, it is necessary to supply power to the operational amplifier. In addition, even when other circuit configurations are used, it is necessary to supply power to the detection circuit. It is necessary to pass a larger current through the wiring supplied to the power supply than the wiring for the detection signal. Therefore, it is necessary to increase the thickness of the conductive layer of the flexible wiring portion or to increase the width of the wiring, and the wiring 102 tends to be hard.

  By using this different form, the direction in which the wiring 102 is arranged and the direction in which the distance between the transducers 101 expands and contracts are substantially orthogonal to each other. Therefore, even if the wiring 102 becomes hard due to the power supply line, the probe surface is covered. It is possible to make it difficult to prevent deformation along the shape of the specimen. Therefore, it is possible to provide an acoustic wave probe that can more accurately obtain information from the subject along the surface shape of the subject even when the capacitive transducer is used.

  As yet another form of the present embodiment, as shown in FIG. 9-4(a), it is possible to adopt a configuration in which the flexible wiring 220 is used to realize the acoustic wave transducer 101 and the wiring 102 connecting the acoustic wave transducer 101. Here, the flexible wiring 220 is configured to be placed on the holding film 104. For example, it is possible to adopt a configuration in which the plurality of transducers 101 connected by the wiring 102 between the grooves 105 in FIG. 4-1 are replaced by the plurality of transducers 200 connected by the flexible wiring 220.

  In FIG. 9-4(a), the chip forming the capacitance transducer has the through wiring 210. Therefore, the wirings connected to the electrodes 202 and 203 on the front surface of the chip (the surface on which the capacitance transducer is formed) are drawn to the electrodes on the back surface of the chip (the surface on which the capacitance transducer is not formed). The conductive layer of the flexible wiring is exposed corresponding to the position of the electrode on the back surface of the chip (not shown), and the chip and the electrode of the flexible wiring are electrically connected by the solder bump 211. A space between the chip and the flexible wiring is filled with an underfill material 212. The presence of the underfill material 212 can reduce the influence of the occurrence of defects in the electrical connection portion due to moisture or the like, and enhance the electrical connection reliability. The detection circuit 402 is connected to the tip of the wiring in the flexible wiring (not shown).

  A configuration in which the detection circuit 402 is arranged on the back surface of the flexible wiring 220 (the surface on which the chip is not formed) can also be adopted. This allows the detection circuit to be arranged close to the capacitance transducer. As described above, the reception characteristic of the capacitance transducer is greatly affected by the parasitic capacitance of the wiring, but with this configuration, excellent reception characteristics can be obtained.

  At this time, the detection circuit 402 and the flexible wiring 220 can be easily connected by using solder. The electrical connection between the detection circuit 402 and the flexible wiring is preferably covered with a sealing material 230 such as epoxy resin. As a result, it is possible to reduce the influence of the occurrence of defects in the electrical connection portion due to moisture and the like, and it is possible to enhance the reliability of electrical connection. Since the wiring 102 between the acoustic wave transducers 101 is composed of the flexible wiring 220 in the configuration of FIG. 9-4(a), the wiring density can be increased.

  As yet another form of the present embodiment, as shown in FIG. 9-4(b), it is possible to employ a configuration in which the rigid flexible substrate 242 is used to realize the acoustic wave transducer 101 and the wiring 102 connecting the acoustic wave transducer 101. .. In this case as well, the rigid flexible substrate 242 is mounted on the holding film 104. In FIG. 9-4(b), the rigid flexible substrate 242 is composed of a rigid and hard-to-deform rigid portion 243 made of glass epoxy and copper foil, and a flexible wiring portion that is soft and easily bent, and is integrally formed. In the flexible wiring part, a thin conductive layer 222 is sandwiched between insulating films 221 and 223 of polyimide, like the flexible wiring 220. The plurality of rigid parts 243 are connected by a flexible wiring part, electrodes corresponding to the electrodes of the chip 199 are provided on the rigid parts, and the electrodes are electrically connected by solder bumps 211. An underfill material 212 is filled between the rigid portion 243 and the chip 199. Since it is fixed by the underfill material, even when the chip and the rigid part expand and contract due to temperature change, the stress applied to the bump part 211 can be reduced, and the occurrence of defects in the electrical connection part can be suppressed.

  The detection circuit 402 is arranged on the surface of the rigid portion on which the chip is not arranged. In this another mode, since the detection circuit is arranged in the rigid portion 243 having the same configuration as that of a normal circuit board, it is possible to arrange complicated wiring. Therefore, the wiring between the capacitance type transducer 200 and the detection circuit 402 can be made more optimal and have a smaller parasitic capacitance. In this way, the reception characteristic can be further improved. The detection circuit 402 and the rigid portion 243 can be easily connected by using solder. Further, it is desirable that the electrical connection portion between the detection circuit 402 and the rigid portion 243 be covered with a sealing material 230 such as epoxy resin. As a result, it is possible to reduce the influence of the occurrence of defects in the electrical connection portion due to moisture and the like, and it is possible to enhance the reliability of electrical connection.

  The glass epoxy material of the rigid portion 243 is formed by laminating a glass cloth impregnated with an epoxy adhesive and then heating and pressing the resin to cure it. The adhesive is fixed to the flexible wiring. Since the glass epoxy material is formed by periodically laminating glass cloth having a certain thickness, it is possible to attenuate ultrasonic waves that have entered. Therefore, it is possible to reduce the influence of the ultrasonic waves transmitted through the chip 199 on the reception characteristics due to the waves reflected by the support member 104. In particular, it is more preferable to use a combination of a plurality of types of layers having different thicknesses of glass cloth because the transmitted ultrasonic waves can be attenuated. With the configuration of FIG. 9-4(b), it is possible to provide a probe having good ultrasonic transmission/reception characteristics and a higher wiring density.

(Ninth Embodiment)
The photoacoustic wave (ultrasonic wave) probe according to any one of the first to eighth embodiments, in addition to receiving the photoacoustic wave (ultrasonic wave) utilizing the photoacoustic effect, transmits the ultrasonic wave to the subject. The reflected ultrasonic waves can be received. Then, it can be applied to an information acquisition device that acquires information on a subject based on the acquired signal. Here, the reception of the photoacoustic wave generated by the photoacoustic effect in the subject and the transmission/reception of the ultrasonic wave to/from the subject are performed by using the acoustic wave probe of the present invention to acquire the information of the subject.

  FIG. 10 shows a schematic diagram of the information acquisition device according to the present embodiment. In FIG. 10, reference numeral 706 is an ultrasonic transmission/reception signal, 707 is a transmitted ultrasonic wave, 708 is a reflected ultrasonic wave, and 709 is reproduced image information by ultrasonic wave transmission/reception. Although omitted in FIG. 10, the acoustic wave probe having the configuration described in any of the first to eighth embodiments is used.

  The information acquisition device of the present embodiment performs pulse echo (transmission/reception of ultrasonic waves) in addition to reception of photoacoustic waves to form an image. Since the reception of the photoacoustic wave is the same as that of the tenth embodiment described later, pulse echo (transmission/reception of ultrasonic waves) will be described here. Based on the transmission signal 706 of the ultrasonic wave, the acoustic wave transducers 803 arranged on the holding film 802 (such as the holding film 104 in FIG. 1) of the acoustic wave probe head toward the measurement object 800 (99). The ultrasonic waves 706 are output (transmitted). The ultrasonic waves are reflected due to the difference in the intrinsic acoustic impedance of the object inside the measuring object 800. The reflected ultrasonic waves 708 are received by a plurality of acoustic wave transducers 803, and information about the size, shape, and time of the received signal is sent to the image information generation device 805 as an ultrasonic received signal 706. Here, an ultrasonic gel 801 is filled between the holding film 802 and the subject 800 in order to avoid attenuation of acoustic waves (ultrasonic waves) due to bubbles. On the other hand, the information on the size, shape, and time of the transmitted ultrasonic wave is stored in the image information generation device 805 as ultrasonic wave transmission information. The image information generation device 805 generates an image signal of the measurement target 800 based on the ultrasonic reception signal 706 and the ultrasonic transmission information, and outputs it as reproduction image information 709 of ultrasonic transmission/reception.

  The image display 806 displays the measurement target 800 as an image based on two pieces of information, reproduced image information 705 by a photoacoustic signal and reproduced image information 709 by ultrasonic transmission/reception. Since the acoustic wave probe according to the present embodiment is unlikely to cause deterioration of the characteristics of the acoustic wave transducer due to attachment, it is possible to accurately acquire a photoacoustic wave, and the same probe can accurately detect an ultrasonic wave. Can send and receive. Therefore, a high-quality photoacoustic image and an ultrasonic image having the same coordinate system can be generated.

  In the present embodiment, the transducer may receive at least ultrasonic waves from the subject, and the processing unit may acquire the information of the subject using the ultrasonic wave reception signal from the transducer. Here, the capacitive transducer may also transmit ultrasonic waves toward the subject, but other transducers may transmit ultrasonic waves. Further, it is also possible to adopt a mode in which only ultrasonic waves are received without receiving photoacoustic waves.

  As described above, the acoustic wave probe detects photoacoustic waves and/or ultrasonic waves from the subject located at a position corresponding to the concave support member (holding film 802) such as a hemisphere. Then, the signal processing unit can construct a biological tissue image of the subject from the photoacoustic wave and/or ultrasonic wave signals acquired by the acoustic wave probe. Therefore, when the acoustic wave probe of the present embodiment is used, different subject information can be acquired, so that the subject information can be obtained in more detail and a subject image having a large amount of information can be generated. Further, since the same acoustic wave transducer is used to receive the photoacoustic wave and transmit/receive the ultrasonic wave, the object information obtained by each can be obtained as information with almost no coordinate deviation. Therefore, it is possible to display images with little deviation when the respective subject images are superimposed.

  Of course, as described in the above embodiment, when acquiring the object information, the positional relationship between the object and the acoustic wave transducer can be easily and stably fixed substantially along the surface of the object. It is possible to efficiently receive high-quality acoustic waves corresponding to various target parts.

(Tenth Embodiment)
The photoacoustic wave (ultrasonic wave) probe according to any one of the first to eighth embodiments can be used for receiving a photoacoustic wave (ultrasonic wave) utilizing a photoacoustic effect, and information including the same can be used. It can be applied to the acquisition device. The operation of the ultrasonic measurement device according to the present embodiment will be specifically described with reference to FIG. First, based on the light emission instruction signal 701, the light 702 (pulse light) is emitted from the irradiation unit 804 to irradiate the measurement target (subject) 800 (99) with the light 702. A photoacoustic wave (ultrasonic wave) 703 is generated in the measurement object 800 by irradiation of the light 702, and the ultrasonic wave 703 is generated by a plurality of acoustic wave transducers 803 arranged on the holding film 802 (104) included in the acoustic wave probe. To receive. An ultrasonic gel 801 is filled between the holding film 802 and the subject 800 in order to avoid attenuation of acoustic waves (ultrasonic waves) due to bubbles. In FIG. 11 as well, a portion corresponding to the holding film 104 is omitted, but the configuration described in any of the first to eighth embodiments is used. Information about the size, shape, and time of the received signal is sent as a received signal 704 of the photoacoustic wave to the image information generation device 805 that is the signal processing unit. On the other hand, the size, shape, and time information (light emission information) of the light 703 from the irradiation unit 804 is stored in the image information generation device 805 of the photoacoustic signal. The photoacoustic signal image information generation device 805 generates an image signal of the measurement object 800 based on the photoacoustic wave reception signal 703 and the light emission information, and outputs it as reproduction image information 705 by the photoacoustic signal. The image display 806 displays the measurement object 800 as an image based on the reproduction image information 705 based on the photoacoustic signal.

  The photoacoustic wave (ultrasonic) probe according to the present embodiment is capable of relatively efficiently and uniformly irradiating a subject with light from a light source arranged at the center of the bottom of a concave portion such as a hemisphere. Therefore, accurate information about the subject can be obtained and a high-quality image can be generated. Of course, as described in the above embodiment, when acquiring the object information, it is possible to easily and stably fix the positional relationship between the object and the acoustic wave transducer substantially along the surface of the object. It is possible to efficiently receive high-quality acoustic waves corresponding to various target parts.

99 subject 100 acoustic wave probe 101 acoustic wave transducer 102 wiring 104 holding film

Claims (21)

A plurality of acoustic wave transducers arranged two-dimensionally and a wiring electrically connecting the plurality of acoustic wave transducers are provided, and an interval between the plurality of acoustic wave transducers adjacent to each other in the extension/contraction direction is expanded/contracted. It is possible, the wiring is arranged to extend in a direction intersecting the expansion and contraction direction, the wiring is not provided between the acoustic wave transducers adjacent to the expansion and contraction direction,
The acoustic wave probe, wherein the expansion/contraction direction is more easily expanded/contracted than a direction intersecting the expansion/contraction direction.   The acoustic wave probe according to claim 1, wherein the acoustic wave transducer and the wiring are supported by a holding film having flexibility.   The acoustic wave probe according to claim 2, wherein a groove extending in the wiring direction is formed in the holding film between a plurality of rows of acoustic wave transducers adjacent to each other in the expansion/contraction direction.   The acoustic wave probe according to claim 2, wherein a plurality of through holes are formed in the holding film between the rows of the plurality of acoustic wave transducers adjacent to each other in the expansion/contraction direction.   The acoustic wave probe according to any one of claims 1 to 4, wherein the direction of the wiring and the direction of expansion and contraction are substantially orthogonal to each other.   The acoustic wave probe according to any one of claims 1 to 5, wherein a plurality of acoustic wave transducers adjacent to each other in the extension and contraction direction are connected by an elastic spring member.   The acoustic wave probe according to any one of claims 1 to 6, wherein a plurality of regions in which the expansion/contraction direction and the wiring direction are not parallel to each other are present in the entire region.   The acoustic wave probe according to claim 2, further comprising an irradiation unit that irradiates the subject with light, and the irradiation unit is supported by the holding film.   The acoustic wave probe according to claim 2, further comprising a support member having a concave shape that supports the holding film. 10. The acoustic wave according to claim 9 , wherein the holding film is arranged so as to be sandwiched between a holding means and a subject arranged in a space between the supporting member and the holding film. probe. The acoustic wave probe according to claim 10 , wherein the holding means is a bag filled with gas. The acoustic wave probe according to any one of claims 1 to 11 , wherein the acoustic wave transducer is a capacitance type transducer. The acoustic wave transducer according to claim 12 , further comprising: a detection circuit that includes a transimpedance circuit using an operational amplifier and that detects a current when the acoustic wave transducer receives an acoustic wave. Wave probe. A drive receiving circuit for transmitting and receiving a signal related to an acoustic wave, the circuit including a circuit that detects a current when the acoustic wave transducer receives the acoustic wave, is connected to the acoustic wave transducer. Item 12. The acoustic wave probe according to Item 12 . The acoustic wiring according to any one of claims 1 to 14 , wherein the wiring is a flexible wiring in which a conductive layer is sandwiched by insulating films, and the acoustic wave transducer is provided on the flexible wiring. Wave probe. The said wiring is a rigid flexible substrate containing a flexible wiring part and a rigid part, The said acoustic wave transducer is provided in the said rigid part, The acoustic as described in any one of Claim 1 to 14 characterized by the above-mentioned. Wave probe. 17. An acoustic wave probe according to any one of claims 1 to 16 , and a signal processing unit for converting a signal detected by the acoustic wave probe into a signal representing information of a subject. Information acquisition device. The information acquisition device according to claim 17 , wherein the signal processing unit converts a signal detected by the acoustic wave probe into an image signal of a subject. The acoustic wave probe, the information acquiring apparatus according to claim 17 or 18, characterized in that detecting the photoacoustic wave from the object generated by the photoacoustic effect. The acoustic wave probe, the information acquisition apparatus according to any one of 19 claims 17, characterized in that to detect ultrasonic waves from the subject. The information acquisition apparatus according to claim 20 , wherein the acoustic wave probe transmits and receives ultrasonic waves.

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