JP4619845B2 - Ultrasonic probe and ultrasonic diagnostic apparatus - Google Patents

Description

  The present invention relates to an ultrasonic probe having a wide directivity and an ultrasonic diagnostic apparatus including the ultrasonic probe.

  2. Description of the Related Art There is known an ultrasonic diagnostic apparatus that scans an inside of a subject with ultrasonic waves and images an internal state of the subject based on a reception signal generated from a reflected wave from the inside of the subject. Such an ultrasonic diagnostic apparatus transmits ultrasonic waves into a subject using an ultrasonic probe including a piezoelectric vibrator, and receives reflected waves generated by acoustic impedance mismatches within the subject using the ultrasonic probe. Generate a received signal.

  The ultrasonic probe oscillates based on the transmission signal to generate ultrasonic waves, and a plurality of piezoelectric vibrators that receive the reflected waves and generate reception signals are arranged in the scanning direction. In such an ultrasonic probe, a delay time is given to a signal applied to the piezoelectric vibrator, and ultrasonic waves to be transmitted and received are electronically focused and deflected for scanning. Since the ultrasonic beam can be made fine by focusing the ultrasonic wave, the resolution can be improved. Further, a wide viewing angle can be obtained by deflecting the ultrasonic beam into a fan shape. In order to focus and deflect the ultrasonic waves, it is important to widen the ultrasonic directivity characteristics of the individual piezoelectric vibrators with respect to the arrangement direction of the piezoelectric vibrators. Various proposals have been made in the past to widen the directivity characteristics of ultrasonic waves (for example, Patent Document 1).

  By the way, in order to achieve acoustic matching between the acoustic impedance of the piezoelectric vibrator and the acoustic impedance of the subject, an acoustic matching layer divided into a plurality in the scanning direction is provided on the piezoelectric vibrator, and the acoustic matching layer is interposed therebetween. Ultrasound is being transmitted and received. In some cases, the acoustic matching layer has a multi-layer structure, and the acoustic impedance is reduced as the layer is farther from the piezoelectric vibrator to improve the acoustic matching.

  In this way, the acoustic matching between the piezoelectric vibrator and the subject is improved because if the difference between the acoustic impedance of the piezoelectric vibrator and the acoustic impedance of the subject is large, ultrasonic waves are transmitted from the piezoelectric vibrator to the subject. This is because the reflection loss of the ultrasonic wave at the subject increases. This is because the ultrasonic wave cannot be efficiently transmitted to the subject, and an image with good image quality cannot be obtained.

  Here, the configuration of a conventional ultrasonic probe will be described with reference to FIG. FIG. 5 is a diagram of the ultrasonic probe as viewed from a direction orthogonal to the scanning direction (arrangement direction). In the ultrasonic probe, a piezoelectric vibrator 22 is provided on a back material 21, and acoustic matching layers 23 and 24 are provided on the piezoelectric vibrator 22. Further, an acoustic lens (not shown) is provided on the acoustic matching layer 24. The piezoelectric vibrator 22 and the acoustic matching layers 23 and 24 are divided and arranged in the scanning direction (arrangement direction). In such an ultrasonic probe, the piezoelectric vibrator 22 transmits and receives ultrasonic waves via the acoustic matching layers 23 and 24.

  When the wavelength of the ultrasonic wave is λ, the thickness t (width in the transmission / reception direction of the ultrasonic wave) of the acoustic matching layers 23 and 24 is generally designed to be about (λ / 4) from the viewpoint of acoustic matching. In designing the ultrasonic probe, the effective diameter of the ultrasonic probe, the number of elements, the width d1 (width in the arrangement direction) of the ultrasonic transducer 22 and the like are given priority, so that the acoustic matching layers 23 and 24 are designed. In many cases, the width (width in the arrangement direction) is determined by the design.

Japanese Patent Laid-Open No. 11-205899

  However, the ultrasonic probe is designed with priority given to the dimensions of the piezoelectric vibrator 22, and the value of the aspect ratio (width d1 / thickness t) of each acoustic matching layer 24 divided into a plurality of parts is about 1. In this case, the vibration in the transmission / reception direction in which the ultrasonic wave propagates interferes with the vibration (lateral vibration) in the scanning direction (arrangement direction) orthogonal to the transmission / reception direction, thereby narrowing the directivity characteristics of the piezoelectric vibrator 22 in the arrangement direction. End up. Accordingly, since the directivity angle of the ultrasonic beam is limited, the sensitivity is insufficient at a large deflection angle, and as a result, a good image cannot be obtained, resulting in a deterioration in diagnostic ability. Therefore, in order to improve the diagnostic ability, it is necessary to improve (widen) the directivity characteristics of each piezoelectric vibrator.

  The present invention solves the above-described problems and reduces the aspect ratio of the acoustic matching layer by making the width in the direction in which the acoustic matching layers are arranged narrower than the width in the direction in which the piezoelectric vibrators are arranged. Therefore, an object is to improve (widen) the directivity of each piezoelectric vibrator by reducing the influence of lateral vibration.

The invention according to claim 1 includes a plurality of piezoelectric vibrators arranged in a predetermined direction, and an acoustic matching layer provided to overlap each of the piezoelectric vibrators, and the acoustic matching layers are stacked. An ultrasonic probe that transmits and receives ultrasonic waves in a direction in which each acoustic matching layer has a width in the arranged direction that is narrower than a width in the transmission and reception direction of each acoustic matching layer, and each piezoelectric vibration The width of the arranged direction of the child is constant in the transmission / reception direction of the piezoelectric vibrators, and the width of the acoustic matching layer in the arranged direction is the arrangement of the piezoelectric vibrators. This is an ultrasonic probe characterized by being narrower than the width in the selected direction.

  The invention according to claim 2 is the ultrasonic probe according to claim 1, wherein a width of each acoustic matching layer in the transmission / reception direction is substantially equal to a width of the piezoelectric vibrators in the arranged direction. It is characterized by being equal.

  In the present invention, for example, under the condition that the width of each acoustic matching layer in the transmission / reception direction is substantially equal to the width in the arrangement direction of each piezoelectric vibrator, the width in the arrangement direction of each acoustic matching layer is By making it narrower than the width in the direction, the aspect ratio of each acoustic matching layer is reduced. By reducing the aspect ratio in this manner, it is possible to reduce lateral vibration and to widen the directivity characteristics of the piezoelectric vibrator.

The invention according to claim 3 has a plurality of piezoelectric vibrators arranged in a predetermined direction and a plurality of acoustic matching layers provided to overlap each piezoelectric vibrator, and the acoustic matching layer An ultrasonic probe that transmits and receives ultrasonic waves in a direction in which the layers are stacked, and the width of the arranged layers of the tip layers of the plurality of layers is greater than the width of the tip layers in the direction of transmission and reception The width of the arranged directions of the piezoelectric vibrators is constant in the direction of transmission / reception of the piezoelectric vibrators, and the width of the arranged direction of the tip layer is the width of the piezoelectric vibrators. The ultrasonic probe is characterized by being narrower than the width of the transducers in the arranged direction.

  The invention according to claim 4 is the ultrasonic probe according to claim 3, wherein the width of the transmitting / receiving direction of the tip layer is substantially equal to the width of the piezoelectric vibrators in the arranged direction. It is characterized by this.

  The invention according to claim 5 is the ultrasonic probe according to claim 3 or 4, wherein the width of the arranged direction is closer to the layer provided farther from the piezoelectric vibrator. It is characterized by being narrow.

  A sixth aspect of the present invention is the ultrasonic probe according to any one of the first to fifth aspects, wherein the piezoelectric transducers are arranged between the piezoelectric vibrators and the acoustic matching layers in the arranged direction. It is characterized by being filled with a filler.

  According to a seventh aspect of the present invention, the ultrasonic probe according to any one of the first to sixth aspects and the ultrasonic wave are transmitted / received to / from the subject by the ultrasonic probe, and the reflected wave from the subject is detected. And an image generation means for generating an ultrasonic image based on the ultrasonic diagnostic apparatus.

  According to the present invention, since the width in the direction in which the acoustic matching layers are arranged is narrower than the width in the direction in which the piezoelectric vibrators are arranged, it is possible to reduce the lateral vibration in the acoustic matching layer, thereby reducing the piezoelectric vibration. It becomes possible to widen the directivity of the child. Specifically, under the condition that the width of the acoustic matching layer in the transmission / reception direction is substantially equal to the width of the direction in which the piezoelectric vibrators are arranged, the width in the direction in which the acoustic matching layers are arranged is arranged in the piezoelectric vibrators. Since it is narrower than the width in the direction, the width in the direction in which the acoustic matching layers are arranged becomes narrower than the width in the transmission / reception direction of the acoustic matching layer. That is, since the aspect ratio is smaller than 1, lateral vibration can be reduced, and as a result, the directivity can be widened. This is the same when receiving ultrasonic waves. By widening the directivity characteristics of the piezoelectric vibrator, it is possible to collect biological information from a wider angle, thereby improving the diagnostic ability.

  An ultrasonic probe according to an embodiment of the present invention will be described with reference to FIGS.

  The configuration of the ultrasonic probe according to the embodiment of the present invention will be described with reference to FIG. FIG. 1 is a perspective view showing a schematic configuration of an ultrasonic probe according to an embodiment of the present invention. The ultrasonic probe comprises a head side and a cable side, and FIG. 1 shows the head side of the ultrasonic probe.

  As shown in the figure, the ultrasonic probe 1 is provided with a piezoelectric vibrator 3 on a back material 2. The piezoelectric vibrators 3 are divided and arranged in a plurality in the scanning direction (arrangement direction). A first acoustic matching layer 4 is provided on the piezoelectric vibrator 3, and a second acoustic matching layer 5 is provided on the first acoustic matching layer 4. The first acoustic matching layer 4 and the second acoustic matching layer 5 are divided into a plurality of rows in the scanning direction (arrangement direction). Furthermore, an acoustic lens 6 is provided on the second acoustic matching layer 5.

  The backing material 2 attenuates and absorbs ultrasonic vibration components that are not necessary for image extraction of the ultrasonic diagnostic apparatus among ultrasonic vibrations oscillated from the piezoelectric vibrator 3 and ultrasonic vibrations at the time of reception. Generally, a material obtained by mixing a microballoon or the like with ferrite rubber, epoxy, urethane rubber or the like is used for the backing material 2.

The piezoelectric vibrator 3 is made of a ceramic material such as lead titanate zirconate Pb (Zr, Ti) O ₃ , lithium niobate (LiNbO ₃ ), barium titanate (BaTiO ₃ ), or lead titanate (PbTiO ₃ ). Electrodes (not shown) are formed on the upper and lower surfaces of the piezoelectric vibrator 3. Since the piezoelectric vibrator 3 is divided and arranged in a plurality in the scanning direction, the ultrasonic probe 1 according to this embodiment is referred to as a one-dimensional array ultrasonic probe.

  The first acoustic matching layer 4 and the second acoustic matching layer 5 are made of an epoxy resin or a plastic material, and the acoustic impedance of the second acoustic matching layer 5 is the first in order to improve acoustic matching. The acoustic matching layer 4 is designed to be smaller than the acoustic impedance. By making the acoustic matching layer have a plurality of layer structures, the generation of signal loss due to the difference in acoustic impedance with the body surface of the subject combined with the acoustic lens 6 is suppressed. In this embodiment, two acoustic matching layers are provided, but there may be one or three or more layers. Detailed structures of the first acoustic matching layer 4 and the second acoustic matching layer 5 will be described later.

  The acoustic lens 6 contacts the body surface of the subject and mediates transmission / reception of ultrasonic waves. By this acoustic lens 6, an acoustic focus in the slice direction (direction orthogonal to the scanning direction) is formed at a predetermined depth from the body surface. The acoustic focus in the scanning direction is established by switching and controlling transmission / reception timings of the plurality of piezoelectric vibrators 3 arranged in a strip shape in the scanning direction.

  Fillers such as silicone rubber, urethane rubber, or epoxy resin are provided in the divided grooves of the piezoelectric vibrator 3, the first acoustic matching layer 4, and the second acoustic matching layer 5 that are divided into a plurality of parts in order to maintain mechanical strength. 7 is filled.

  Next, the configuration of the piezoelectric vibrator 3, the first acoustic matching layer 4, and the second acoustic matching layer 5 will be described with reference to FIG. FIG. 2 is a view of the ultrasonic probe viewed from a direction orthogonal to the scanning direction (arrangement direction), and the acoustic lens 6 and the filler 7 are omitted in order to simplify the description.

  As shown in FIG. 2A, the width of the second acoustic matching layer 5 in the scanning direction (arrangement direction) is a width d3, and the width of the piezoelectric vibrator 3 in the scanning direction is a width d1. Here, the relationship of width d3 <width d1 is established. That is, the width of the second acoustic matching layer 5 in the scanning direction is narrower than the width of the piezoelectric vibrator 3 in the scanning direction. Since the width of the first acoustic matching layer 4 in the scanning direction is the width d1, it is equal to the width of the piezoelectric vibrator 3 in the scanning direction. Therefore, when viewed from the whole acoustic matching layer, the width in the scanning direction of the layer at the tip (second acoustic matching layer 5) is narrower than the width in the scanning direction of the piezoelectric vibrator 3. The width between the piezoelectric vibrators 3 (the width of the dividing groove) is defined as a width d2. Further, the thickness t (width in the transmission / reception direction of the ultrasonic wave) of the second acoustic matching layer 5 is substantially equal to the width d1 of the piezoelectric vibration 3 in the scanning direction.

  In this way, the scanning of the second acoustic matching layer 5 is performed under the condition that the thickness t of the second acoustic matching layer (width in the transmission / reception direction of ultrasonic waves) is substantially equal to the width d1 of the piezoelectric vibrator 3 in the scanning direction. Since the width in the direction is narrower than the width in the scanning direction of the piezoelectric vibrator 3, the width d3 in the scanning direction of the second acoustic matching layer 5 is equal to the thickness t of the second acoustic matching layer 5 (super Narrower than the width in the direction of transmission and reception of sound waves. That is, thickness t> width d3, and the aspect ratio (width d3 / thickness t) of the second acoustic matching layer 5 is smaller than 1.

  As described above, since the aspect ratio of the second acoustic matching layer 5 is smaller than 1, it is possible to reduce the transverse vibration of the ultrasonic wave and to improve the directivity characteristics of the piezoelectric vibrator 3. As a result, sensitivity at a wide directivity angle can be improved, and diagnostic ability can be improved.

  The directivity characteristic of the piezoelectric vibrator 3 and the acoustic matching by the acoustic matching layer are in a trade-off relationship. That is, in order to widen the directivity of the piezoelectric vibrator 3, the aspect ratio (width d3 / thickness t) of the second acoustic matching layer 5 may be made smaller than 1, but the second acoustic matching layer 5 The sensitivity is lowered by reducing the width d3 in the scanning direction. Therefore, it is necessary to design the ultrasonic probe so that a good image for diagnosis can be obtained in consideration of directivity and acoustic matching. For example, if the aspect ratio of the second acoustic matching layer 5 is slightly smaller than 1, it is better in diagnosis than an ultrasonic probe having an aspect ratio of approximately 1 due to the effect of widening the directivity. An image can be obtained. Specifically, even if the width d3 is reduced until the aspect ratio (width d3 / thickness t) is about 2/3, a good image can be obtained for diagnosis due to the effect of wide directivity. . That is, even if the acoustic matching is deteriorated, the directivity is improved more than the transmission sensitivity is lowered, so that the image used for diagnosis is good.

  Another example is shown in FIG. In this example, the width in the scanning direction of the second acoustic matching layer 5 and the width in the scanning direction of the first acoustic matching layer 41 are equal to each other and have a width d3. The width of the piezoelectric vibrator 3 in the scanning direction is a width d1. Therefore, the widths of the first acoustic matching layer 41 and the second acoustic matching layer 5 in the scanning direction are both narrower than the width of the piezoelectric vibrator 3 in the scanning direction.

  As described above, when the width of the first acoustic matching layer 41 and the second acoustic matching layer 5 in the scanning direction is narrower than the width of the piezoelectric vibrator 3 in the scanning direction, FIG. Similarly to the example shown, since the aspect ratio of the first acoustic matching layer 41 and the second acoustic matching layer 5 can be made smaller than 1, it is possible to reduce the transverse vibration of the ultrasonic waves. As a result, the directivity characteristics of the piezoelectric vibrator 3 can be widened.

  FIG. 2C shows still another example. The width of the first acoustic matching layer 41 in the scanning direction is a width d3, and the width of the second acoustic matching layer 51 in the scanning direction is a width d4. The width of the piezoelectric vibrator 3 in the scanning direction is a width d1. Here, the relationship of width d4 <width d3 <width d1 is established. That is, the width of the first acoustic matching layer 41 in the scanning direction is narrower than the width of the piezoelectric vibrator 3 in the scanning direction, and the width of the second acoustic matching layer 51 in the scanning direction is the first acoustic matching layer. The width of the layer 41 is narrower than the width in the scanning direction. Accordingly, the acoustic matching layer provided farther from the piezoelectric vibrator 3 has a narrower width in the scanning direction.

  As described above, even when the acoustic matching layer provided farther from the piezoelectric vibrator 3 has a narrower width in the scanning direction, as in the example shown in FIGS. Since the aspect ratio of the acoustic matching layer 41 and the second acoustic matching layer 51 can be made smaller than 1, it is possible to reduce the transverse vibration of the ultrasonic waves. As a result, the directivity characteristics of the piezoelectric vibrator 3 can be improved.

  In the example shown in FIGS. 1 and 2, the example in which two acoustic matching layers are provided has been described. However, the acoustic matching layer may be one layer or three or more layers. For example, when only one acoustic matching layer is provided, only the second acoustic matching layer 5 is provided in the ultrasonic probe shown in FIG. Even with such a structure, the directivity characteristics of the piezoelectric vibrator 3 can be expanded.

  Next, directivity characteristics of the ultrasonic probe shown in FIG. 2A will be described with reference to FIG. FIG. 3 is a graph showing the directivity characteristics of the ultrasonic probe according to the embodiment of the present invention. This graph is obtained by performing a simulation by a known finite element method (FEM). An ultrasonic probe having a structure shown in FIG. 2A was used as the ultrasonic probe. The dimensions of the ultrasonic probe are shown below.

  In the ultrasonic probe shown in FIG. 2A, the width d1 in the scanning direction of the piezoelectric vibrator 3 is set to 0.06 [mm], and the width d2 between the elements is set to 0.04 [mm]. The width d3 in the scanning direction of the second acoustic matching layer 5 was set to 0.04 [mm], and the width (thickness) t in the transmission / reception direction was set to 0.06 [mm]. Therefore, the aspect ratio (width d3 / thickness t) of the second acoustic matching layer 5 is 2/3, which is smaller than 1. Further, the width d1 in the scanning direction of the piezoelectric vibrator 3 and the thickness t (width in the transmission / reception direction of ultrasonic waves) of the second acoustic matching layer 5 have the same value.

  As a comparative example, a simulation was also performed for the ultrasonic probe according to the related art shown in FIG. In the ultrasonic probe according to the related art, the width d1 in the scanning direction of the piezoelectric vibrator 22 is set to 0.06 [mm], and the width d2 between the elements is set to 0.04 [mm]. Since the width in the scanning direction of the first acoustic matching layer 23 and the second acoustic matching layer 24 is the same as the width d1 in the scanning direction of the piezoelectric vibrator 22, the first acoustic matching layer 23 and the second acoustic matching layer 24 The width d1 in the scanning direction of the matching layer 24 is 0.06 [mm]. The width (thickness) t in the transmission / reception direction of the second acoustic matching layer 24 was set to 0.06 [mm]. Therefore, the aspect ratio (width d1 / thickness t) of the second acoustic matching layer 24 is 1. The width d1 in the scanning direction of the piezoelectric vibrator 22 and the thickness t (width in the transmission / reception direction of ultrasonic waves) of the second acoustic matching layer 24 have the same value.

  Then, one piezoelectric vibrator 3 and 22 was driven at a frequency of 11 [MHz], and the directivity characteristics in the scanning direction were calculated. The horizontal axis in FIG. 3 is the directivity angle [degree], and the vertical axis is the relative transmission sensitivity [dB]. The angle is an angle when the ultrasonic beam is deflected, and indicates an angle in the scanning direction (arrangement direction) of the piezoelectric vibrator 3.

  In the figure, graph A is a simulation result for the ultrasonic probe according to this embodiment. For example, the directivity angle at −20 [dB] is about ± 40 [degrees]. Further, in the figure, a graph B is a simulation result for the ultrasonic probe according to the related art. For example, the directivity angle at −20 [dB] is about ± 32 [degrees]. From this result, it is understood that the directivity angle of the ultrasonic probe according to this embodiment is about ± 8 [degrees] wider than the directivity angle of the conventional ultrasonic probe. In addition to the -20 [dB], it can be seen that the directivity angle of the ultrasonic probe according to this embodiment is wider than the directivity angle of the conventional ultrasonic probe.

  Thus, according to the ultrasonic probe 1 according to this embodiment, the directivity characteristics of the piezoelectric vibrator can be widened as compared with the ultrasonic probe according to the related art. As a result, it is possible to improve sensitivity at a wide directivity angle and improve diagnostic ability.

  Note that the width d3 in the scanning direction of the second acoustic matching layer 5 is narrowed until the aspect ratio becomes 2/3. However, at this level, the transmission sensitivity is not lowered to the extent that the image used for diagnosis is affected. As the characteristics become wider, a better image than before can be obtained and the diagnostic ability can be improved.

  In general, the ultrasonic probe is formed by laminating the first and second acoustic matching layers 4 and 5 on the piezoelectric vibrator 3, and then the piezoelectric vibrator 3, the first acoustic matching layer 4 and the second acoustic matching layer. The acoustic matching layer 5 is manufactured by dividing it into a plurality of pieces by a dicing blade (blade). Specifically, after dicing (first dicing) the piezoelectric vibrator 3 and the first and second acoustic matching layers 4 and 5 according to a predetermined pitch, the second acoustic matching layer 5 is formed with a wider groove width. And dicing (second dicing) at the same pitch as the first dicing. Then, the ultrasonic probe 1 shown in FIG. 2A is filled by filling the groove 7 with a filler 7 and further adhering an acoustic lens 6 on the second acoustic matching layer 5. Get.

  In this manufacturing, the piezoelectric vibrator 3 and the first and second acoustic matching layers 4 and 5 may be divided using a dicing blade made of the same material, or dicing blades made of different materials may be used. Since the piezoelectric vibrator and the acoustic matching layer are made of different materials, a dicing blade suitable for dividing the material may be used. For example, after the piezoelectric vibrator 3 and the first and second acoustic matching layers 4 and 5 are divided by the same dicing blade so that the dividing groove is d2, it is suitable for the material (resin) of the second acoustic matching layer 5. Alternatively, the dicing blade may be used to divide the second acoustic matching layer 5 so that the width is d3. Since the piezoelectric vibrator is made of a ceramic material and the acoustic matching layer is made of a resin or plastic material, the acoustic matching layer is generally softer than the piezoelectric vibrator. Therefore, when the second acoustic matching layer 5 is diced, the second acoustic matching layer 5 can be diced satisfactorily by dicing by increasing the diameter of the diamond particles of the dicing blade.

  Although the so-called one-dimensional ultrasonic probe has been described in the above embodiment, the present invention is not limited to the one-dimensional ultrasonic probe. Even if it is a two-dimensional ultrasonic probe in which the piezoelectric vibrator and the acoustic matching layer are arranged in a matrix, the same operation and effect can be achieved. In the case of a two-dimensional ultrasonic probe, the width of the acoustic matching layer in the scanning direction is made narrower than the width of the piezoelectric vibrator in the scanning direction. Alternatively, in the direction orthogonal to the scanning direction, the width of the acoustic matching layer may be narrower than the width of the piezoelectric vibrator. Thus, by making the width of the acoustic matching layer narrower than the width of the piezoelectric vibrator, the aspect ratio of the acoustic matching layer can be reduced, the transverse vibration of the ultrasonic wave can be reduced, and the orientation of the piezoelectric vibrator can be reduced. It becomes possible to widen the characteristics.

  Next, an ultrasonic diagnostic apparatus including the ultrasonic probe 1 will be described with reference to FIG. FIG. 4 is a block diagram showing a schematic configuration of the ultrasonic diagnostic apparatus according to the embodiment of the present invention.

  The ultrasonic diagnostic apparatus 10 mainly includes an ultrasonic probe 1, a transmission / reception unit 11, a signal processing unit 12, a DSC 13, an image processing unit 14, a display device 15, and a control unit 16. The ultrasonic diagnostic apparatus 10 is characterized by the ultrasonic probe 1, and other transmitting / receiving units 11 and the like are known.

  As the ultrasonic probe 1, the ultrasonic probe according to this embodiment described above is used. The transmission / reception unit 11 includes a transmission unit and a reception unit. The transmission / reception unit 11 supplies an electrical signal to the ultrasonic probe 1 to generate an ultrasonic wave and receives an echo signal received by the ultrasonic probe 1.

  The signal processing unit 12 includes a known B-mode processing circuit, Doppler processing circuit, and color mode processing circuit. The data output from the transmission / reception unit 11 is subjected to predetermined processing in any processing circuit. The B-mode processing circuit visualizes echo amplitude information and generates B-mode ultrasonic raster data from the echo signal. The Doppler processing circuit extracts the Doppler shift frequency component and further performs FFT processing or the like to generate data having blood flow information. The color mode processing circuit visualizes the moving blood flow information and generates color ultrasonic raster data. Blood flow information includes information such as speed, dispersion, and power, and blood flow information is obtained as binarized information.

  A DSC 13 (Digital Scan Converter) converts ultrasonic raster data into data represented by orthogonal coordinates (scan conversion process) in order to obtain an image represented by an orthogonal coordinate system. For example, when scan conversion processing is performed on data output from the B-mode processing circuit, tomographic image data representing the tissue shape of the subject as two-dimensional information is generated. The image processing unit 14 performs various image processing. For example, voxel data is generated from tomographic image data, and volume rendering processing is further performed to generate three-dimensional image data.

  The display device 15 includes a monitor such as a liquid crystal display, and displays a tomographic image, a three-dimensional image, and the like. The control unit 16 includes a CPU, and controls each processing unit by executing a control program, an image generation program, and the like stored in a storage unit (not shown). The storage unit includes a memory such as a ROM and a hard disk, and stores image data, various setting conditions, a program, and the like. In addition, a pointing device such as a joystick, an operation unit (not shown) such as a switch or a TCS (Touch Command Screen) is provided, and various settings relating to ultrasonic transmission / reception conditions are input by the operator.

  According to the ultrasonic diagnostic apparatus 10 including the ultrasonic probe 1 according to this embodiment, since the directional characteristics of the piezoelectric vibrator 3 are wide, it is possible to collect biological information from a wider angle and improve the diagnostic ability. It becomes possible.

1 is a perspective view showing a schematic configuration of an ultrasonic probe according to an embodiment of the present invention. FIG. 2 is a diagram when the ultrasonic probe of FIG. 1 is viewed from a direction orthogonal to a scanning direction (arrangement direction), and is a diagram for explaining the widths of a piezoelectric vibrator and an acoustic matching layer. It is a graph showing the directional characteristic of the ultrasonic probe which concerns on embodiment of this invention. 1 is a block diagram illustrating a schematic configuration of an ultrasonic diagnostic apparatus including an ultrasonic probe according to an embodiment of the present invention. It is the figure which looked at the conventional ultrasonic probe from the direction orthogonal to a scanning direction (array direction), and is a figure for demonstrating the width | variety of a piezoelectric vibrator and an acoustic matching layer.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Ultrasonic probe 2 Back material 3 Piezoelectric vibrator 4, 41 1st acoustic matching layer 5, 51 2nd acoustic matching layer 6 Acoustic lens 7 Filling material

Claims (7)

A plurality of piezoelectric vibrators arranged in a predetermined direction; and an acoustic matching layer provided on each of the piezoelectric vibrators, and transmitting and receiving ultrasonic waves in a direction in which the acoustic matching layers are stacked. An ultrasonic probe,
The width of each acoustic matching layer in the arranged direction is narrower than the width in the transmission / reception direction of each acoustic matching layer, and the width in the arranged direction of each piezoelectric vibrator is the respective piezoelectric vibrator. The ultrasonic probe is constant in the transmission / reception direction, and the width of each of the acoustic matching layers in the arranged direction is narrower than the width of each of the piezoelectric vibrators in the arranged direction.   The ultrasonic probe according to claim 1, wherein a width of each acoustic matching layer in the transmission / reception direction is substantially equal to a width of the piezoelectric vibrators in the arranged direction. A plurality of piezoelectric vibrators arranged in a predetermined direction, and an acoustic matching layer composed of a plurality of layers provided on each of the piezoelectric vibrators, and ultrasonic waves in a direction in which the acoustic matching layers are overlaid. An ultrasonic probe for transmitting and receiving
Of the plurality of layers, the width of the arranged layer of the tip layer is narrower than the width of the tip layer in the transmission / reception direction, and the width of the arranged direction of each piezoelectric vibrator is The ultrasonic wave characterized by being constant in the transmission / reception direction of the piezoelectric vibrator, wherein the width of the arranged layer of the tip layer is narrower than the width of the piezoelectric vibrator in the arranged direction. probe.   The ultrasonic probe according to claim 3, wherein a width of the tip layer in the transmission / reception direction is substantially equal to a width of the piezoelectric vibrators in the array direction.   5. The ultrasonic probe according to claim 3, wherein a width of the layer arranged farther from the piezoelectric vibrator has a narrower width in the arranged direction. 6.   The super array according to any one of claims 1 to 5, wherein a filler is filled between the piezoelectric vibrators and between the acoustic matching layers in the arranged direction. Acoustic probe. The ultrasonic probe according to any one of claims 1 to 6,
Image generating means for transmitting and receiving ultrasonic waves to and from the subject by the ultrasonic probe, and generating an ultrasonic image based on a reflected wave from the subject;
An ultrasonic diagnostic apparatus comprising:

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