JP2017225621A - Ultrasonic transducer and ultrasonic endoscope - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ultrasonic transducer and an ultrasonic endoscope that can prevent deformation due to aged deterioration.SOLUTION: An ultrasonic transducer includes: a first element capable of transmitting and receiving an ultrasonic wave; a second element provided adjacent to the first element, and capable of transmitting and receiving the ultrasonic wave; at least one acoustic matching layer laminated in the first element and the second element, respectively, and matching the sound impedance of first element and the second element with the sound impedance for observation; a sheet-like outer-most layer provided in the supersonic transmission direction to the acoustic matching layer, and holding an interval between the first element and the second element to a predetermined interval through the acoustic matching layer; the acoustic matching layer extending along the supersonic transmission direction, and between the first element and the second element and/or continuing to the first element; and a shape-retaining member having a tooth part entering between the acoustic matching layers continuing to the second element.SELECTED DRAWING: Figure 4

Description

  The present invention relates to an ultrasonic transducer and an ultrasonic endoscope that transmit ultrasonic waves to an observation target, receive ultrasonic echoes reflected by the observation target, and convert them into electrical signals.

  Ultrasound may be used to observe the characteristics of the biological tissue or material that is the object of observation. Specifically, the ultrasonic observation apparatus performs predetermined signal processing on the ultrasonic echo received from the ultrasonic transducer that transmits and receives ultrasonic waves, thereby acquiring information regarding the characteristics of the observation target.

  The ultrasonic transducer converts an electrical pulse signal into an ultrasonic pulse (acoustic pulse) and irradiates the observation target, and converts an ultrasonic echo reflected from the observation target into an electrical echo signal for output. And an acoustic matching layer that matches the acoustic impedance of the piezoelectric element with the acoustic impedance of the observation target. For example, an ultrasonic echo is acquired from an observation target by arranging a plurality of elements along a predetermined direction and electronically switching elements involved in transmission and reception. Examples of the above-described element include a piezoelectric element.

  As types of ultrasonic transducers, there are known a plurality of types having different ultrasonic beam transmission / reception directions, such as a convex type, a linear type, and a radial type. Among them, in the convex ultrasonic transducer, a plurality of elements are arranged in a convex shape along a curved surface, and each emits an ultrasonic beam toward the radially outer side of the curved surface (see, for example, Patent Document 1). ). An ultrasonic transducer disclosed in Patent Document 1 includes a plurality of elements arranged on a plane on a sheet-like elastic member corresponding to an acoustic matching layer, and an end of the element opposite to the side connected to the elastic member. It is curved to approach.

Japanese Utility Model Publication No.59-973

  By the way, the conventional ultrasonic transducer may not be able to maintain its shape due to deformation of the acoustic matching layer over time and change in pitch between elements.

  The present invention has been made in view of the above, and an object thereof is to provide an ultrasonic transducer and an ultrasonic endoscope that can suppress deformation over time.

  In order to solve the above-described problems and achieve the object, an ultrasonic transducer according to the present invention is provided adjacent to the first element capable of transmitting and receiving ultrasonic waves, and the first element. The second element capable of transmitting and receiving the ultrasonic wave, and the first element and the second element are stacked on each other, and the acoustic impedance of the first element and the second element and the sound to be observed At least one acoustic matching layer that matches impedance, and is provided in the transmission direction of the ultrasonic wave with respect to the acoustic matching layer, and the first element and the second element via the acoustic matching layer A sheet-like outermost layer that holds the gap between the first element and the second element, and / or the first element, and / or the first element. The acoustic matching layer connected to the element of The shape retaining member having a tooth portion that enters between the second of the acoustic matching layer connected to the element, characterized by comprising a.

  The ultrasonic transducer according to the present invention is the ultrasonic transducer according to the above invention, wherein the outermost layer has a surface facing the first element and the second element, the surface of the first element and the second element. Among the end portions, at least the end portions on the opposite side to the outermost layer side are curved in a direction approaching each other.

  In the ultrasonic transducer according to the present invention, in the above invention, the first element and the second element are formed with ground electrodes, and the shape holding member is made of a conductive material. The ground electrode and the shape holding member are electrically connected to each other.

  The ultrasonic transducer according to the present invention is the ultrasonic transducer according to the above invention, wherein the first element and the second element have a prismatic shape and a ground electrode is formed. The second elements are aligned in the longitudinal direction, and the shape holding members are provided on both end sides in the longitudinal direction of the first element and the second element, respectively, and at least one of the shape holding members is It is formed using a conductive material, and is electrically connected to the ground electrode.

  An ultrasonic endoscope according to the present invention is an ultrasonic endoscope having an insertion portion that is inserted into a subject, the first element capable of transmitting and receiving ultrasonic waves, and the first A second element provided adjacent to the element and capable of transmitting and receiving the ultrasonic wave, and stacked on the first element and the second element, respectively, the first element and the second element; At least one acoustic matching layer that matches the acoustic impedance of the element and the acoustic impedance of the observation target, and is provided in the transmission direction of the ultrasonic wave with respect to the acoustic matching layer. A sheet-like outermost layer that holds a predetermined distance between the first element and the second element, and extends along the transmission direction of the ultrasonic wave, and the first element and the second element; And / or before connecting to the first element An acoustic matching layer, characterized by comprising a shape retaining member having a plurality of teeth that has entered between the second of said acoustic matching layer continuous with the element.

  According to the present invention, there is an effect that deformation over time can be suppressed.

FIG. 1 is a diagram schematically showing an endoscope system according to Embodiment 1 of the present invention. FIG. 2 is a perspective view schematically showing the distal end configuration of the insertion portion of the ultrasonic endoscope according to the first embodiment of the present invention. FIG. 3 is a partial cross-sectional view corresponding to the line AA shown in FIG. FIG. 4 is a schematic diagram showing the configuration of the main part of the ultrasonic transducer module according to Embodiment 1 of the present invention, and schematically shows part of the configuration of the piezoelectric element, the first acoustic matching layer, and the shape holding member. FIG. 5 is a plan view in the direction of arrow B in FIG. FIG. 6 is a partial cross-sectional view schematically showing the distal end configuration of the insertion portion of the ultrasonic endoscope according to the first modification of the first embodiment of the present invention. FIG. 7 is a schematic diagram illustrating the configuration of the main part of the ultrasonic transducer module according to the first modification of the first embodiment of the present invention, in which the configuration of the piezoelectric element, the first acoustic matching layer, and the shape maintaining member is illustrated. It is a perspective view which shows a part typically. FIG. 8 is a schematic diagram showing the configuration of the main part of the ultrasonic transducer module according to the second modification of the first embodiment of the present invention, in which the piezoelectric element, the first acoustic matching layer, and the shape retention are shown. It is a schematic diagram explaining the structure of a member. FIG. 9 is a perspective view schematically showing the distal end configuration of the insertion portion of the ultrasonic endoscope according to the second embodiment of the present invention. FIG. 10 is a schematic diagram illustrating the configuration of the main part of the ultrasonic transducer module according to Embodiment 2 of the present invention, and schematically illustrates part of the configuration of the piezoelectric element, the first acoustic matching layer, and the shape holding member. FIG. 11 is a plan view in the direction of arrow C in FIG.

  DESCRIPTION OF EMBODIMENTS Hereinafter, modes for carrying out the present invention (hereinafter, embodiments) will be described with reference to the drawings. The present invention is not limited to the embodiments described below. Furthermore, the same code | symbol is attached | subjected to the same part in description of drawing.

(Embodiment 1)
FIG. 1 is a diagram schematically showing an endoscope system according to Embodiment 1 of the present invention. The endoscope system 1 is a system that performs ultrasonic diagnosis in a subject such as a person using an ultrasonic endoscope. As shown in FIG. 1, the endoscope system 1 includes an ultrasonic endoscope 2, an ultrasonic observation device 3, an endoscope observation device 4, a display device 5, and a light source device 6.

  The ultrasonic endoscope 2 converts an electrical pulse signal transmitted from the ultrasonic observation apparatus 3 into an ultrasonic pulse (acoustic pulse) to an object by an ultrasonic transducer provided at the distal end thereof. While irradiating, the ultrasonic echo reflected from the subject is converted into an electrical echo signal expressed by a voltage change and output.

  The ultrasonic endoscope 2 usually has an imaging optical system and an imaging device, and is inserted into a digestive tract (esophagus, stomach, duodenum, large intestine) or respiratory organ (trachea / bronchi) of a subject to digest Imaging of either a tube or a respiratory organ can be performed. In addition, surrounding organs (pancreas, gallbladder, bile duct, biliary tract, lymph node, mediastinal organ, blood vessel, etc.) can be imaged using ultrasound. In addition, the ultrasonic endoscope 2 has a light guide that guides illumination light to be irradiated onto a subject during optical imaging. The light guide has a distal end portion that reaches the distal end of the insertion portion of the ultrasonic endoscope 2 into the subject, and a proximal end portion that is connected to the light source device 6 that generates illumination light.

  As shown in FIG. 1, the ultrasonic endoscope 2 includes an insertion unit 21, an operation unit 22, a universal cord 23, and a connector 24. The insertion part 21 is a part inserted into the subject. As shown in FIG. 1, the insertion portion 21 is provided on the distal end side, and is a rigid distal end portion 211 that holds the ultrasonic transducer 7, and a bending portion that is connected to the proximal end side of the distal end portion 211 and can be bent. 212 and a flexible tube portion 213 connected to the proximal end side of the bending portion 212 and having flexibility. Here, although not shown in the drawings, a light guide that transmits illumination light supplied from the light source device 6 and a plurality of signal cables that transmit various signals are routed inside the insertion portion 21. In addition, a treatment instrument insertion passage for inserting the treatment instrument is formed.

  The ultrasonic transducer 7 is a convex type that scans electronically by providing a plurality of piezoelectric elements in an array and electronically switching the piezoelectric elements involved in transmission / reception or delaying transmission / reception of each piezoelectric element. This is an ultrasonic transducer. The configuration of the ultrasonic transducer 7 will be described later.

  FIG. 2 is a perspective view schematically showing the distal end configuration of the insertion portion of the ultrasonic endoscope according to the first embodiment. As shown in FIG. 2, the tip 211 has an ultrasonic transducer module 214 that holds the ultrasonic transducer 7, an illumination lens 215 a that collects the illumination light and emits it outside, and one of the imaging optical systems. And an endoscope module 215 having an objective lens 215b that takes in light from the outside. The endoscope module 215 is formed with a treatment instrument protrusion 215 c that communicates with a treatment instrument insertion passage formed in the insertion section 21 and projects the treatment instrument from the distal end of the insertion section 21. In the treatment instrument insertion path, the vicinity of the end connected to the treatment instrument protrusion 215c is inclined with respect to the longitudinal axis of the insertion portion 21, and the treatment instrument protrudes from the treatment instrument protrusion 215c in a direction inclined with respect to the longitudinal axis. It is provided to do. The longitudinal axis here is an axis along the longitudinal direction of the insertion portion 21. In the bending portion 212 and the flexible tube portion 213, the axial direction changes depending on each position, but in the rigid tip portion 211, the longitudinal axis is an axis that forms a constant straight line.

  The operation unit 22 is connected to the proximal end side of the insertion unit 21, and is a part that receives various operations from a user such as a doctor. As shown in FIG. 1, the operation unit 22 includes a bending knob 221 for performing a bending operation on the bending unit 212 and a plurality of operation members 222 for performing various operations. In addition, the operation section 22 is formed with a treatment instrument insertion port 223 that communicates with the treatment instrument insertion path and allows the treatment instrument to be inserted into the treatment instrument insertion path.

  The universal cord 23 is a cable that extends from the operation unit 22 and includes a plurality of signal cables that transmit various signals and an optical fiber that transmits illumination light supplied from the light source device 6.

  The connector 24 is provided at the tip of the universal cord 23. The connector 24 includes first to third connector portions 241 to 243 to which the ultrasonic cable 31, the video cable 41, and the optical fiber cable 61 are connected, respectively.

  The ultrasonic observation apparatus 3 is electrically connected to the ultrasonic endoscope 2 via the ultrasonic cable 31 (FIG. 1), and outputs a pulse signal to the ultrasonic endoscope 2 via the ultrasonic cable 31. At the same time, an echo signal is input from the ultrasonic endoscope 2. Then, the ultrasonic observation device 3 performs a predetermined process on the echo signal to generate an ultrasonic image.

  The endoscope observation apparatus 4 is electrically connected to the ultrasonic endoscope 2 via a video cable 41 (FIG. 1) and inputs an image signal from the ultrasonic endoscope 2 via the video cable 41. . Then, the endoscope observation apparatus 4 performs a predetermined process on the image signal to generate an endoscope image.

  The display device 5 is configured by using a liquid crystal or organic EL (Electro Luminescence), a projector, a CRT (Cathode Ray Tube), and the like, and an ultrasonic image generated by the ultrasonic observation device 3 or an endoscope observation device 4. The endoscope image etc. which were produced | generated by are displayed.

  The light source device 6 is connected to the ultrasonic endoscope 2 via the optical fiber cable 61 (FIG. 1), and supplies illumination light for illuminating the inside of the subject via the optical fiber cable 61 to the ultrasonic endoscope 2. To do.

  Next, the configuration of the ultrasonic transducer 7 provided at the distal end of the insertion portion 21 will be described with reference to FIGS. FIG. 3 is a partial cross-sectional view corresponding to the line AA shown in FIG. In the first embodiment, the ultrasonic transducer 7 is a convex ultrasonic transducer as shown in FIG. 2, and is a one-dimensional array (1D array) in which a plurality of piezoelectric elements 71 are arranged in a line. It will be explained as being. In other words, in the ultrasonic transducer 7 according to the first embodiment, the plurality of piezoelectric elements 71 are arranged along the outer surface forming the curved surface of the ultrasonic transducer 7, include the longitudinal axis, and Send and receive ultrasound on a plane parallel to the longitudinal axis.

  The ultrasonic transducer 7 has a prismatic shape and a plurality of piezoelectric elements 71 arranged in the longitudinal direction, and a plurality of first elements provided on the outer surface side of the ultrasonic transducer 7 with respect to the piezoelectric elements 71. A first acoustic matching layer 72; a sheet-like second acoustic matching layer 73 provided on the opposite side of the first acoustic matching layer 72 that contacts the piezoelectric element 71; and a side of the piezoelectric element 71 that contacts the first acoustic matching layer 72. A backing material 74 provided on the opposite side of the first acoustic matching layer 72, an acoustic lens 75 provided on the opposite side of the second acoustic matching layer 73 in contact with the first acoustic matching layer 72, and the first acoustic matching layer 72. A plurality of tooth portions that are formed between the wall portion 76 and a lid portion 77 that is formed using a hard resin and seals the opening on one end side of the wall portion 76 and between the adjacent first acoustic matching layers 72. And two shape holding members 78 having a comb shape.

  The piezoelectric element 71 converts an electrical pulse signal into an acoustic pulse and irradiates the subject, and converts an ultrasonic echo reflected by the subject into an electrical echo signal expressed by a voltage change and outputs the electrical echo signal. . The piezoelectric element 71 extends in a column shape. In the piezoelectric element 71, for example, a signal input / output electrode 71a is provided on the main surface on the backing material 74 side, and a ground surface for grounding is provided on the main surface on the first acoustic matching layer 72 side of the piezoelectric element 71. An electrode 71b is provided. Each electrode is formed using a conductive metal material or resin material. The main surface here means an acoustic radiation surface and a surface facing the acoustic radiation surface, and a surface intersecting the main surface is called a side surface. In the first embodiment, when a certain piezoelectric element 71 is the first element, the piezoelectric element 71 adjacent to the first element is the second element.

  The first acoustic matching layer 72 and the second acoustic matching layer 73 allow the acoustic impedance of the piezoelectric element 71 and the acoustic impedance of the observation target to be efficiently transmitted between the piezoelectric element 71 and the observation target. And match. The first acoustic matching layer 72 and the second acoustic matching layer 73 are made of different materials. The first embodiment will be described as having two acoustic matching layers (the first acoustic matching layer 72 and the second acoustic matching layer 73). It is good also as three or more layers.

  The first acoustic matching layer 72 is provided according to the piezoelectric element 71 and extends in a columnar shape. That is, the plurality of first acoustic matching layers 72 are provided so as to be connected to the first element or the second element, respectively. The first acoustic matching layer 72 is provided with a ground electrode 72 a that is electrically connected to the ground electrode 71 b of the piezoelectric element 71. The ground electrode 72a is formed of a conductive material larger than the acoustic impedance of the piezoelectric element 71, and functions as a dematching layer. The piezoelectric element 71 is grounded to the outside through the ground electrode 72a. In the first embodiment, description will be made assuming that the piezoelectric element 71 is fixed to the first acoustic matching layer 72 with an adhesive or the like.

  The second acoustic matching layer 73 has, for example, a sheet shape that is curved along the arrangement of the plurality of piezoelectric elements 71. In other words, the second acoustic matching layer 73 has a curved surface facing the piezoelectric element 71. Note that, similarly to the first acoustic matching layer 72, it may be provided according to each piezoelectric element 71.

  The backing material 74 attenuates unnecessary ultrasonic vibration generated by the operation of the piezoelectric element 71. The backing material 74 is filled in a hollow space formed by the piezoelectric element 71, the second acoustic matching layer 72, the wall portion 76, and the lid portion 77. The backing material 74 is formed using a material having a large attenuation rate, for example, an epoxy resin in which a filler such as alumina or zirconia is dispersed, or a rubber in which the filler is dispersed.

  The acoustic lens 75 covers the outer surfaces of the first acoustic matching layer 72, the second acoustic matching layer 73, the wall portion 76, and the lid portion 77, and forms the outer surface of the ultrasonic transducer 7. The acoustic lens 75 is formed using silicone, polymethylpentene, epoxy resin, polyetherimide, etc., and has a function of narrowing the ultrasonic wave with one surface being convex or concave, and the second acoustic matching layer. The ultrasonic wave that has passed through 73 is emitted to the outside, or an ultrasonic echo from the outside is captured. The acoustic lens 75 can be arbitrarily provided, and may be configured without the acoustic lens 75.

  In the first embodiment, the second acoustic matching layer 73 corresponds to the outermost layer of the present invention. When three or more acoustic matching layers are provided, the outermost sheet-like acoustic matching layer (the side opposite to the piezoelectric element 71 side) is the outermost layer. Further, when the outermost acoustic matching layer is divided according to the piezoelectric element 71, or when there is one acoustic matching layer, the acoustic lens 75 is the outermost layer.

  The shape holding member 78 is provided on the end side of the piezoelectric element 71 that intersects the direction in which the plurality of piezoelectric elements 71 are arranged and the direction perpendicular to the ultrasonic wave transmission / reception direction. The shape holding member 78 is formed using a hard insulating material.

  FIG. 4 is a schematic diagram showing the configuration of the main part of the ultrasonic transducer module according to Embodiment 1 of the present invention, and schematically shows part of the configuration of the piezoelectric element, the first acoustic matching layer, and the shape holding member. FIG. 5 is a plan view in the direction of arrow B in FIG. The shape holding member 78 has a main body portion 78 a that is curved along the arrangement of the plurality of first acoustic matching layers 72, and a plurality of tooth portions 78 b that enter between the adjacent first acoustic matching layers 72. . That is, in the first embodiment, each tooth portion 78b enters between the first acoustic matching layer 72 connected to the first element and the first acoustic matching layer 72 connected to the second element. In the first embodiment, the main body portion 78a and the first acoustic matching layer 72 are described as not contacting each other. However, the main body portion 78a and the first acoustic matching layer 72 may be brought into contact with each other.

  Each tooth part 78b may be fitted in a gap formed between the adjacent first acoustic matching layers 72, or may be accommodated without a gap between the adjacent first acoustic matching layers 72, You may make it accommodate with a some space | gap between the adjacent 1st acoustic matching layers 72. FIG.

  The ultrasonic transducer 7 having the above configuration is designed to be supervised by the piezoelectric element 71 by the input of the pulse signal, via the first acoustic matching layer 72, the second acoustic matching layer 73, and the acoustic lens 75. Irradiate sound waves. At this time, in the piezoelectric element 71, the side opposite to the side where the first acoustic matching layer 72, the second acoustic matching layer 73 and the acoustic lens 75 are disposed attenuates unnecessary vibration from the piezoelectric element 71 by the backing material 74. Yes. The ultrasonic wave reflected from the observation target is transmitted to the piezoelectric element 71 through the acoustic lens 75, the second acoustic matching layer 73, and the first acoustic matching layer 72. The piezoelectric element 71 is vibrated by the transmitted ultrasonic wave, and the piezoelectric element 71 converts the vibration into an electrical echo signal and outputs it as an echo signal to the ultrasonic observation apparatus 3.

  As shown in FIG. 3, the ultrasonic transducer module 214 includes a housing 214 a in which a housing hole 214 b that can accommodate the ultrasonic transducer 7 described above is formed. The ultrasonic transducer module 214 includes an ultrasonic transducer 7, a cable that forms part of a path that electrically connects the ultrasonic transducer 7 (ultrasonic transducer module 214) and the ultrasonic observation device 3. A relay board (not shown) for relaying the electrical connection between them. The relay substrate is electrically connected to the ground electrode 71b through the signal input / output electrode 71a and the ground electrode 72a.

  According to the first embodiment described above, the tooth portions 78b of the shape holding member 78 are inserted between the adjacent first acoustic matching layers 72, and the pitch of the adjacent first acoustic matching layers 72 is maintained. Since it did in this way, even if it is a case where the 1st acoustic matching layer 72 and another component are deform | transformed by aged deterioration, the time-dependent deformation | transformation of the ultrasonic transducer | vibrator 7 can be suppressed.

  Further, according to the first embodiment, since the displacement of the arrangement of the first acoustic matching layer 72 can be suppressed even when the first acoustic matching layer 72 is deformed by the shape holding member 78, for example, the first acoustic matching layer 72 is used. It is possible to prevent the end of the adjacent piezoelectric element 71 opposite to the side connected to the first acoustic matching layer 72 from inclining and coming into contact with each other due to the displacement of the arrangement. Thereby, it is possible to suppress a short circuit due to the contact between the piezoelectric elements 71.

(Modification 1 of Embodiment 1)
FIG. 6 is a partial cross-sectional view schematically showing the distal end configuration of the insertion portion of the ultrasonic endoscope according to the first modification of the first embodiment of the present invention. FIG. 7 is a schematic diagram illustrating the configuration of the main part of the ultrasonic transducer module according to the first modification of the first embodiment of the present invention, in which the configuration of the piezoelectric element, the first acoustic matching layer, and the shape maintaining member is illustrated. It is a perspective view which shows a part typically. In the first modification, instead of the shape holding member 78 of the ultrasonic transducer 7 described above, a shape holding member 78A having conductivity is provided.

  The shape holding member 78 </ b> A is provided on the end side of the piezoelectric element 71 that intersects the direction in which the plurality of piezoelectric elements 71 are arranged and the direction perpendicular to the ultrasonic wave transmission / reception direction. The shape holding member 78A is formed using a conductive material having rigidity.

  The shape holding member 78 </ b> A has a main body portion 78 c that is curved along the arrangement of the plurality of first acoustic matching layers 72, and a plurality of tooth portions 78 d that enter between the adjacent first acoustic matching layers 72. . In the first modification, the main body portion 78c and the first acoustic matching layer 72 are in contact with each other. Specifically, the main body 78c is a part of the surface of the first acoustic matching layer 72 and is in contact with a part of the surface including the ground electrode 72a. For this reason, the relay board and the ground electrode 71b can be electrically connected by electrically connecting the relay board and the shape holding member 78A.

  According to the first modification, the main body portion 78c of the conductive shape holding member 78A is brought into contact with the ground electrode 72a of the first acoustic matching layer 72, so that the relay substrate is interposed via the shape holding member 78A. And the ground electrode 71b can be electrically connected. Thereby, the relay substrate and the ground electrode 71b can be easily electrically connected without directly connecting the ground electrode 72a of each first acoustic matching layer 72 and the relay substrate.

  In the first modification, the above-described effects can be obtained as long as at least the main body portion 78c has conductivity. That is, in the shape holding member 78A, the plurality of tooth portions 78d may be formed of an insulating material.

  In the first modification, one shape holding member 78A may be formed of a conductive material, and the other shape holding member 78A may be formed of an insulating material. In this case, the conductive shape holding member 78A and the relay board are connected.

(Modification 2 of Embodiment 1)
FIG. 8 is a schematic diagram illustrating the configuration of the main part of the ultrasonic transducer module according to the second modification of the first embodiment of the present invention, in which the configuration of the piezoelectric element, the first acoustic matching layer, and the shape maintaining member is illustrated. It is a perspective view which shows a part typically. In the second modification, the above-described ultrasonic vibrator is formed by inserting the above-described shape holding member 78 between the adjacent piezoelectric elements 71. That is, in the second modification, each tooth portion 78b enters between the piezoelectric element 71 that is the first element and the piezoelectric element 71 that is the second element. At this time, in order to efficiently perform ultrasonic waves transmitted and received by the piezoelectric element 71, the shape holding member 78 is a part of the piezoelectric element 71, and is a region (de- It is preferably provided in a portion corresponding to the matching layer.

  Here, a manufacturing method for manufacturing the ultrasonic transducer according to the second modification will be described. When manufacturing an ultrasonic transducer, first, the first acoustic matching layer 72 and the second acoustic matching layer 73 are laminated on the piezoelectric element 71. At this time, the ground electrode 71 b in the piezoelectric element 71 and the ground electrode 72 a in the first acoustic matching layer 72 are in contact with each other.

  After the piezoelectric element 71, the first acoustic matching layer 72, and the second acoustic matching layer 73 are stacked, the tooth portion 78b is inserted between the adjacent piezoelectric elements 71, and the second acoustic matching layer 73 is curved.

  Thereafter, the wall portion 76 is erected on the first acoustic matching layer 72, and the backing material 74 is cast using the wall portion 76 as a weir and cured. Thereafter, a lid 77 is formed on the backing material 74 using, for example, an epoxy resin. 3 shows the wall 76 having only two surfaces, it may be formed on the end side of the arranged piezoelectric elements 71 as a frame.

  Thereafter, the acoustic lens 75 is attached to the outer periphery of the first acoustic matching layer 72, the second acoustic matching layer 73, the wall portion 76 and the lid portion 77. Thereby, the ultrasonic transducer | vibrator 7 shown in FIG. 3 is produced.

  According to the second modification, since the tooth portion 78b is inserted between the adjacent piezoelectric elements 71, even when the first acoustic matching layer 72 and other components are deformed due to aging, Short circuit due to contact between the piezoelectric elements 71 can be suppressed.

  In the second modification, if the ultrasonic vibrator is manufactured with the tooth portion 78b inserted between the adjacent piezoelectric elements 71, the adjacent piezoelectric elements 71 are in contact with each other at the time of manufacture and damaged. Can be suppressed.

  In addition, by combining the second modification and the first embodiment, the shape holding member 78 may be provided between the adjacent piezoelectric elements 71 and between the adjacent first acoustic matching layers 72. Good.

(Embodiment 2)
FIG. 9 is a perspective view schematically showing the distal end configuration of the insertion portion of the ultrasonic endoscope according to the second embodiment of the present invention. The second embodiment includes a tip portion 211A instead of the tip portion 211 described above, and the ultrasonic transducer is a radial type.

  As shown in FIG. 9, the tip 211A includes an ultrasonic transducer module 216 having the ultrasonic transducer 8, an illumination lens 217a that collects the illumination light and emits it outside, and a part of the imaging optical system. And an endoscope module 217 having an objective lens 217b for taking in light from the outside. The endoscope module 217 is formed with a treatment instrument protrusion 217 c that communicates with a treatment instrument insertion passage formed in the insertion section 21 and projects the treatment instrument from the distal end of the insertion section 21. In the treatment instrument insertion path, the vicinity of the end connected to the treatment instrument protrusion 217c is inclined with respect to the longitudinal axis of the insertion section 21, and the treatment instrument protrudes from the treatment instrument protrusion 217c in a direction inclined with respect to the longitudinal axis. It is provided to do.

  FIG. 10 is a schematic diagram illustrating the configuration of the main part of the ultrasonic transducer module according to Embodiment 2 of the present invention, and schematically illustrates part of the configuration of the piezoelectric element, the first acoustic matching layer, and the shape holding member. FIG. FIG. 11 is a plan view in the direction of arrow C in FIG. 10, illustrating the configuration of the piezoelectric element, the first acoustic matching layer, the second acoustic matching layer, the acoustic lens, and the shape holding member. The ultrasonic vibrator 8 includes a plurality of the piezoelectric elements 71 arranged in the circumferential direction, and electronically switches the piezoelectric elements 71 related to transmission / reception or delays transmission / reception of each piezoelectric element 71, thereby To scan.

  Specifically, the ultrasonic transducer 8 has a prismatic shape, a plurality of piezoelectric elements 71 that are aligned in the circumferential direction with the longitudinal direction aligned, and the piezoelectric transducer 71. A plurality of first acoustic matching layers 72 provided on the outer surface side, a C-shaped or tubular second acoustic matching layer 73A provided on the opposite side of the first acoustic matching layer 72 to the side in contact with the piezoelectric element 71, and a first The acoustic lens 75 </ b> A provided on the opposite side to the side in contact with the first acoustic matching layer 72 of the two acoustic matching layers 73 </ b> A, and two shape holding members 79. In addition, a backing material is provided on the opposite side of the piezoelectric element 71 from the side in contact with the first acoustic matching layer 73A, for example, between the two shape holding members 79.

  The shape holding member 79 includes a main body 79 a having a flat plate shape and a plurality of teeth 79 provided along the outer periphery of the main body 79 a and entering between the adjacent first acoustic matching layers 72. In the shape holding member 79, the trajectory passing through the tip of each tooth portion 79b forms a circle. Although the tooth part 79b is described as having a tapered tip shape, the tooth part 79b may extend from the center of the shape holding member 79 with the same width.

  According to the second embodiment described above, the tooth portions 79b of the shape holding member 79 are inserted between the adjacent first acoustic matching layers 72, and the pitch of the adjacent first acoustic matching layers 72 is maintained. Since it did in this way, even if it is a case where the 1st acoustic matching layer 72 and another component are deform | transformed by aged deterioration, the time-dependent deformation | transformation of the ultrasonic transducer | vibrator 7 can be suppressed.

  Further, according to the second embodiment, even when the first acoustic matching layer 72 is deformed by the shape holding member 79, the displacement of the arrangement of the first acoustic matching layer 72 can be suppressed. For example, the first acoustic matching layer 72 Due to the dislocation, the end of the adjacent piezoelectric element 71 on the side opposite to the side connected to the first acoustic matching layer 72 can be prevented from inclining and coming into contact with each other. Thereby, it is possible to suppress a short circuit due to the contact between the piezoelectric elements 71.

  In the second embodiment, as in the first modification of the first embodiment described above, at least one shape holding member 79 is formed of a conductive material and is brought into contact with the ground electrode 72a, so that the relay substrate is formed. And the ground electrode 71b may be electrically connected. In this case, in order to ensure contact with the ground electrode 72a, it is preferable to provide the tooth portions 79b intermittently and to have a flat portion between the tooth portions 79b.

  In the second embodiment, the teeth 79b of the shape holding member 79 may be inserted between the piezoelectric elements 71 as in the second modification of the first embodiment described above.

  The embodiments for carrying out the present invention have been described so far, but the present invention should not be limited only by the above-described embodiments and modifications. The present invention is not limited to the embodiments and modifications described above, and can include various embodiments without departing from the technical idea described in the claims. Moreover, you may combine suitably the structure of embodiment and a modification.

  In the first and second embodiments described above, a piezoelectric element has been described as an example of emitting an ultrasonic wave and converting an ultrasonic wave incident from the outside into an echo signal. However, the present invention is not limited to this. An element manufactured using (Micro Electro Mechanical Systems), for example, a C-MUT (Capacitive Micromachined Ultrasonic Transducers) or a P-MUT (Piezoelectric Micromachined Ultrasonic Transducers) may be used.

  Further, the ultrasonic endoscope may be applied to a small-diameter ultrasonic probe that does not have an optical system and performs scanning by mechanically rotating a vibrator. The ultrasonic probe is usually inserted into the biliary tract, bile duct, pancreatic duct, trachea, bronchi, urethra, ureter, and is used for observing surrounding organs (pancreas, lung, prostate, bladder, lymph node, etc.).

  Further, as described above, the ultrasonic transducer may be a convex ultrasonic transducer, a radial ultrasonic transducer, or a linear ultrasonic transducer. When the ultrasonic transducer is a linear ultrasonic transducer, the scanning area is rectangular (rectangular, square), and when the ultrasonic transducer is a radial type or convex type, the scanning area is a sector or a circle. Make a ring. In addition, the ultrasonic endoscope may be one that mechanically scans the ultrasonic transducer, or a plurality of elements are arranged in an array as the ultrasonic transducer, and the elements involved in transmission and reception are switched electronically. Alternatively, electronic scanning may be performed by delaying transmission / reception of each element.

  Moreover, although an example was described as an ultrasonic endoscope, the ultrasonic transducer module of the present invention may be applied to an external ultrasonic probe that emits ultrasonic waves from the body surface of a subject. The extracorporeal ultrasonic probe is usually used for observing an abdominal organ (liver, gallbladder, bladder), breast (particularly mammary gland), and thyroid gland.

DESCRIPTION OF SYMBOLS 1 Endoscope system 2 Ultrasound endoscope 3 Ultrasound observation apparatus 4 Endoscope observation apparatus 5 Display apparatus 6 Light source device 7,8 Ultrasonic transducer 21 Insertion part 22 Operation part 23 Universal code 24 Connector 31 Ultrasonic cable 41 Video cable 61 Optical fiber cable 71 Piezoelectric element 72 First acoustic matching layer 73, 73A Second acoustic matching layer 74 Backing material 75, 75A Acoustic lens 76 Wall portion 77 Lid portion 78, 78A, 79 Shape holding member 78a, 78c, 79a body portion 78b, 78d, 79b tooth portion 211, 211A tip portion 212 bending portion 213 flexible tube portion 214, 216 ultrasonic transducer module 214a housing 214b accommodation hole 215, 217 endoscope module 221 bending knob 222 operation member 223 Treatment tool insertion port

Claims (5)

A first element capable of transmitting and receiving ultrasound;
A second element provided adjacent to the first element and capable of transmitting and receiving the ultrasonic wave;
At least one acoustic matching layer that is stacked on each of the first element and the second element, and that matches the acoustic impedance of the first element and the second element with the acoustic impedance of the observation target;
A sheet-like shape that is provided in the transmission direction of the ultrasonic wave with respect to the acoustic matching layer, and that holds the first element and the second element at a predetermined interval via the acoustic matching layer The outermost layer,
The acoustic matching layer that extends along the transmission direction of the ultrasonic waves, is connected to the first element and the second element, and / or is connected to the first element, and is connected to the second element. A shape-retaining member having a tooth portion that enters between the acoustic matching layer;
An ultrasonic transducer comprising: The outermost layer has a surface facing the first element and the second element, and at least ends of the first element and the second element opposite to the outermost layer side. The ultrasonic transducer according to claim 1, wherein the ultrasonic transducer is curved in a direction in which the is approaching. In the first element and the second element, a ground electrode is formed,
The shape holding member is formed using a conductive material,
The ultrasonic transducer according to claim 1, wherein the ground electrode and the shape holding member are electrically connected. The first element and the second element have a prismatic shape, and a ground electrode is formed,
The first element and the second element are aligned in the longitudinal direction,
The shape holding members are provided on both end sides in the longitudinal direction of the first element and the second element, respectively.
The ultrasonic transducer according to claim 1, wherein at least one of the shape holding members is formed using a conductive material, and is electrically connected to the ground electrode. An ultrasonic endoscope having an insertion portion to be inserted into a subject,
A first element capable of transmitting and receiving ultrasound;
A second element provided adjacent to the first element and capable of transmitting and receiving the ultrasonic wave;
At least one acoustic matching layer that is stacked on each of the first element and the second element, and that matches the acoustic impedance of the first element and the second element with the acoustic impedance of the observation target;
A sheet-like shape that is provided in the transmission direction of the ultrasonic wave with respect to the acoustic matching layer, and that holds the first element and the second element at a predetermined interval via the acoustic matching layer The outermost layer,
The acoustic matching layer that extends along the transmission direction of the ultrasonic waves, is connected to the first element and the second element, and / or is connected to the first element, and is connected to the second element. A shape-retaining member having a plurality of teeth that enter between the acoustic matching layers;
An ultrasonic endoscope characterized by comprising:

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