JP2006167206A - Ultrasonograph - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ultrasonograph which can shorten the calculation time by simplifying the calculation of the delay time in the delay addition processing. <P>SOLUTION: The ultrasonograph herein used has a probe 2 having transducers 1, the first delay addition part for forming a plurality of first receiving beams arrayed in the direction x, the second delay addition part for forming a plurality of second receiving beams arrayed in the direction y and moreover, has a setting part which sets the reference point 17, reception focuses Fy_1-Fy_4 for the formation of the second receiving beams and a virtual axis 21 and determines a plurality of intersections 23 as given when the virtual axis 21 is connected to the center of each of the transducers 1 with the shortest segment. The reception focus is so set that the virtual line 20 passing it crosses the transmission sound axis 16 to be vertical to the direction x. The second delay addition part calculates the reference propagation time to the reference point 17 from each of the intersections 23, the focus propagation time to each reception focus from each intersection 23 to compute the difference from the reference propagation time for each determined focus propagation time, thereby carrying out the delay addition processing. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an ultrasonic diagnostic apparatus having a two-dimensional array, and more particularly to an ultrasonic diagnostic apparatus capable of three-dimensional scanning of a subject.

  In recent years, in an ultrasonic diagnostic apparatus, an array type probe configured by arranging a plurality of transducers (vibrators) in a row or matrix is used. In the ultrasonic diagnostic apparatus, focusing is performed to converge the ultrasonic beam by exciting each transducer at slightly different timings so that the wavefronts of the ultrasonic waves radiated from each transducer are aligned near the focal point. Technology is being used.

  Among the array-type probes, one in which a plurality of transducers are arranged in a matrix is called a “two-dimensional array”. When a two-dimensional array is used, an ultrasonic beam can be deflected and scanned in an arbitrary direction, so that the two-dimensional array is useful for collecting three-dimensional echo data.

  In the ultrasonic diagnostic apparatus, in order to display an ultrasonic image in real time, parallel reception processing is performed in which a plurality of reception beams are formed by one transmission of the ultrasonic beam. However, in order to perform parallel reception processing, delay circuits corresponding to the number of reception channels × the number of parallel simultaneous reception channels are required. Further, when collecting three-dimensional echo data, the number of parallel simultaneous reception channels further increases, so that a huge number of delay circuits are required. In such a case, the manufacturing cost and power consumption of the device are increased.

  For this reason, in the ultrasonic diagnostic apparatus, it has been proposed to reduce the number of delay circuits by dividing the delay addition process into a front stage and a rear stage (see, for example, Patent Document 1). This point will be described with reference to FIG. FIG. 14 is a configuration diagram showing a schematic configuration of a conventional ultrasonic diagnostic apparatus. In FIG. 14, portions relating to the formation of ultrasonic beams and image processing are omitted for explanation of parallel reception processing.

  As shown in FIG. 14, the ultrasonic diagnostic apparatus transmits and receives an ultrasonic beam using a two-dimensional array 102. The two-dimensional array 102 is formed by arranging a plurality of transducers (vibrators) 101 in a matrix along two directions (row direction and column direction) orthogonal to each other. When each transducer 101 receives an ultrasonic beam, it outputs a signal corresponding thereto.

  The ultrasonic diagnostic apparatus also includes column-direction delay addition circuits 103 to 106 and row-direction delay addition circuits 107 to 108, and performs delay addition processing separately in the column direction and the row direction. The column direction delay addition circuits 103 to 106 perform the preceding stage delay addition processing including the parallel parallel reception processing in the column direction. The row direction delay addition circuits 107 to 108 perform subsequent delay addition processing including parallel simultaneous reception processing in the row direction. Further, each of the column direction delay addition circuits 103 to 106 and the row direction delay addition circuits 107 to 108 includes a plurality of delay circuits (not shown).

  Here, the number of transducers 101 in the column direction is “M”, the number of transducers 101 in the row direction is “N”, the number of parallel simultaneous reception channels in the column direction is “K”, and the number of parallel simultaneous reception channels in the row direction is “ L ”.

  Each of the column direction delay addition circuits 103 to 106 performs “M × K” delay addition processing. Further, since the number of columns coincides with the number “N” of the transducers 101 in the row direction, a signal group (time series signal group) having “N × K” signals is generated from the entire column direction delay addition circuits 103 to 106. Output every certain time. The total number of delay circuits required in the column direction delay adder circuits 103 to 106 is “M × K × N”.

  Further, the row direction delay addition circuits 107 to 108 perform a delay addition process in the row direction on “N × K” time-series signal groups output from the entire column direction delay addition circuits 103 to 106. Therefore, the number of delay circuits required in the entire row direction delay adder circuits 107 to 108 is “N × K × L”.

From the above, the total number of delay circuits required in the ultrasonic diagnostic apparatus shown in FIG. 14 is (M × K × N) + (N × K × L) = N × K × (M + L). On the other hand, when it is not divided into the column direction and the row direction, the total number of required delay circuits is (N × K × M × L). Therefore, according to the ultrasonic diagnostic apparatus shown in FIG. 14, parallel reception processing in the row direction and the column direction can be realized with a small circuit scale.
JP 2000-254120 A (page 3 to page 4, FIG. 1)

  However, when the delay addition process is performed separately in the preceding stage and the subsequent stage as described above, a lot of time is required in the delay addition process, particularly in the subsequent stage delay addition process. For this reason, there is a need for an ultrasonic diagnostic apparatus that can calculate the delay time in the later-stage delay addition processing in a short time.

  An object of the present invention is to provide an ultrasonic diagnostic apparatus that can solve the above problems, can easily calculate the delay time in the delay addition process, and can reduce the calculation time.

  To achieve the above object, an ultrasonic diagnostic apparatus according to the present invention includes a probe having a plurality of transducers arranged in a matrix along a first direction and a second direction orthogonal to each other, and the plurality of the plurality of transducers. A delay addition process is performed on the signals detected by the transducers to form a plurality of reception beams arranged in the first direction, and the delay addition is performed by the first delay addition unit. An ultrasonic diagnostic apparatus comprising: a second delay addition unit that further performs delay addition processing on the processed signal to form a plurality of reception beams arranged in the second direction, A reference point located on the transmission sound ray axis of the beam, a plurality of virtual reception focal points for forming the plurality of reception beams arranged along the second direction by the second delay adder, and the transmission sound ray axis A virtual axis passing through the intersection with the transmission / reception surface of the probe and parallel to the second direction is set, and the center of each of the plurality of transducers through which the virtual axis passes or is adjacent to the virtual axis; A setting unit for obtaining a plurality of intersections of the line segment and the virtual axis when the virtual axis is connected by the shortest line segment, and the plurality of virtual reception focal points are virtual that pass through all virtual reception focal points; A line intersects with the transmission sound ray axis and is set to be perpendicular to the first direction, and the second delay adder is configured so that, for each of the plurality of intersection points, from the intersection point to the transmission sound ray axis. The propagation time to the reference point set in the above and the propagation time from the intersection to each of the plurality of virtual reception focal points are calculated, and the propagation time to each of the plurality of reception focal points is the propagation time to the reference point. Calculate the difference between And, and performs the delay addition processing by using the calculated the difference.

  In the ultrasonic diagnostic apparatus according to the present invention, an intersection of the transmission sound ray axis and the transmission / reception wave surface of the probe is located at an array center of the plurality of transducers, and the positions of the plurality of virtual reception focal points are The distance from the array center to each of the plurality of virtual reception focal points may be set to be equal to the distance from the array center to the reference point.

  In the ultrasonic diagnostic apparatus according to the present invention, the second delay adder includes a first propagation time calculation circuit that calculates a propagation time to the reference point, and each of the plurality of virtual reception focal points. It is also possible to adopt a mode provided with a second propagation time calculation circuit for calculating the propagation time and a subtraction circuit for calculating the difference.

  Furthermore, in the ultrasonic diagnostic apparatus according to the present invention, the second delay addition unit calculates a propagation time to the reference point or a propagation time to each of the plurality of virtual reception focal points, Storage means for storing one of the propagation times to the reference point and the propagation times to each of the plurality of virtual reception focal points, the one propagation time and the other propagation time stored in the storage means, And a subtracting circuit for calculating the difference from the above.

  In the ultrasonic diagnostic apparatus according to the present invention, the arrangement of the plurality of virtual reception focal points is set to be line symmetric with respect to the transmission sound ray axis, and the second delay addition unit is The sign inversion circuit further includes a sign inversion circuit that calculates a sign of the calculated difference when the difference is calculated for one virtual reception focus of a pair of virtual reception focal points that are in a line-symmetrical positional relationship with each other. It is also possible to adopt a mode in which the difference with respect to the other virtual reception focus is calculated by inversion.

  Furthermore, in the ultrasonic diagnostic apparatus according to the present invention, the second delay addition unit further includes a multiplication circuit, and the multiplication circuit has the difference between at least one of the plurality of virtual reception focal points. When calculated, the difference for the other virtual reception focus can be calculated by multiplying the calculated difference by a preset constant.

  In the ultrasonic diagnostic apparatus according to the present invention, the plurality of transducers are grouped into a plurality of groups, and each group has an arrangement of the plurality of groups along a first direction and a second direction. It is composed of adjacent transducers so as to form a matrix, and a plurality of phasing adders are provided for each group, and the phasing adders are detected by the transducers constituting the corresponding group. The signal is phased and added, and is output to the first delay adder. The first delay adder performs a delay addition process on the signal output from the phased adder, and the setting unit Are connected to the center of each of a plurality of groups passing through the virtual axis or adjacent to the virtual axis and the virtual axis by the shortest line segment and the virtual axis. It may be a manner of obtaining a plurality of intersections of.

  As described above, according to the ultrasonic diagnostic apparatus of the present invention, when performing parallel reception processing in which a plurality of reception beams are formed by a single transmission of an ultrasonic beam, the delay addition processing in the subsequent stage is compared with the conventional method. The delay time can be easily calculated. Therefore, it is possible to reduce the time required for the delay addition process in the subsequent stage.

(Embodiment 1)
Hereinafter, an ultrasonic diagnostic apparatus according to Embodiment 1 of the present invention will be described with reference to FIGS. First, the configuration of the ultrasonic diagnostic apparatus will be described with reference to FIGS. 1 and 2. FIG. 1 is a block diagram schematically showing the overall configuration of the ultrasonic diagnostic apparatus according to the first embodiment. FIG. 2 is a perspective view showing the configuration of the probe and the delay adder of the ultrasonic diagnostic apparatus in the first embodiment.

  As shown in FIG. 1, the ultrasonic diagnostic apparatus according to the first embodiment includes a probe 2, a first delay adder 3, a second delay adder 4, a setting unit 5, and a transmission pulse. A generation unit 6, an image processing unit 7, and a display unit 8 are provided. The ultrasonic diagnostic apparatus performs parallel reception processing for forming a plurality of reception beams 10 by one transmission of the ultrasonic beam 9. In FIG. 1, F indicates the focal plane of the ultrasonic beam 9.

  The transmission pulse generator 6 generates a transmission pulse and outputs it to a plurality of transducers 1 (see FIG. 2) constituting the probe 2. As a result, an ultrasonic beam is emitted from the probe 2 toward the diagnosis target. The first delay addition unit 3 and the second delay addition unit 4 perform a delay addition process on the ultrasonic echoes reflected by the focal plane F of the ultrasonic beam 9 to form a plurality of reception beams 10. The delay addition processing by the first delay addition unit 3 and the second delay addition unit 4 will be described later.

  The image processing unit 7 forms a tomographic image of a portion to be scanned based on the reception beam 10 formed by the first delay addition unit 3 and the second delay addition unit 4. The display unit 8 is a display device for displaying a tomographic image. Examples of the display device include a CRT display and a liquid crystal display.

  Further, as shown in FIG. 2, in the first embodiment, the probe 2 is a two-dimensional array. The plurality of transducers 1 are arranged in a matrix along a first direction (x direction) and a second direction (y direction) orthogonal to each other. A signal detected by each transducer 1 receiving an ultrasonic echo is output to the first delay adder 3 via the signal line 13 for each transducer 1.

  The first delay addition unit 3 performs delay addition processing on the signals detected by the transducers 1 to form a plurality of reception beams arranged in the x direction. In addition, the second delay adder 4 performs a delay addition process on the signal that has been subjected to the delay addition process by the first delay adder 3 to form a plurality of receptions formed by the first delay adder 3. Each of the beams is divided into a plurality of reception beams arranged along the y direction.

  In the first embodiment, the first delay addition unit 3 includes the same number of first delay addition circuits 11 as the number of columns of the transducers 1 in the x direction. Signals detected by a plurality of transducers 1 in the same row in the x direction are grouped together and subjected to delay addition processing by one first delay addition circuit 11. For this reason, a plurality of reception beams arranged in the x direction are formed by the first delay adder 3.

  The signal processed by each first delay adder circuit 11 is output to the second delay adder 4 via the signal line 14. The number of output channels of each first delay adder circuit 11 is set according to the number of reception beams to be formed. In the example of FIG. 2, since the number of reception beams formed by the first delay addition unit 3 is four as will be described later, the number of output channels of each first delay addition circuit 11 is “4”. Yes.

  In the first embodiment, the second delay addition unit 4 includes the same number of second delay addition circuits 12 as the number of channels of the first delay addition circuit 11. In the example of FIG. 2, the number of delay circuits 12 is “4”. Further, the output channels of the first delay addition circuits 11 located at the same position in the x direction are connected to the same second delay addition circuit 12 by a signal line 14 as one unit. Note that “1, 2,... 16” in the second delay addition circuit 12 shown on the leftmost side in FIG.

  For this reason, the reception beam formed by the first delay adder 3 is divided, and a plurality of reception beams arranged in the y direction are formed. In the example of FIG. 2, as will be described later, the second delay adder 4 divides the reception beam formed by the first delay adder 3 into four, so that the output channel of each second delay adder 12 is output. The number is “4”.

  The setting unit 5 sets the coordinates of points required when the first delay addition unit 3 and the second delay addition unit 4 perform the delay addition process, and sets the coordinates of the first delay addition unit 3 and the second delay addition unit 3. Output to the delay adder 4. In the first embodiment, the setting unit 5 sets coordinates such as a reference point on the transmission sound ray axis of the ultrasonic beam and the reception focus of each reception beam. This point will be described later.

  Next, the coordinate setting by the setting unit 5 and the delay addition processing by the first delay addition unit 3 and the second delay addition unit 4 will be described in more detail with reference to FIGS. FIG. 3 is a perspective view showing a reception focal point set for delay addition processing by the first delay addition unit of the ultrasonic diagnostic apparatus according to Embodiment 1.

  As illustrated in FIG. 3, the setting unit 5 includes a transmission sound ray axis 16 of the ultrasonic beam, a reference point 17 positioned thereon, and reception focal points Fx_1 of the plurality of reception beams formed by the first delay addition unit 3. ~ Fx_4 are set. In the example of FIG. 3, the setting unit 5 sets the transmission sound ray axis 16 so that the intersection point with the transmission / reception wave surface of the probe 2 is the array center 19 of the plurality of transducers 1. Further, the setting unit 5 sets the intersection point between the focal plane F of the ultrasonic beam (see FIG. 1) and the transmission sound ray axis 16 as the reference point 17.

  Further, the setting unit 5 sets the reception focal points Fx_1 to Fx_4 so that the virtual line 18 passing through the reception focal points Fx_1 to Fx_4 intersects the transmission sound ray axis 16 and is perpendicular to the y direction. In the example of FIG. 3, the setting unit 5 arranges the reception focal points Fx_1 to Fx_4 in line symmetry with respect to the transmission sound ray axis 16, and a line connecting the reception focal points Fx_2 and Fx_3 is a reference on the transmission sound ray axis 16. Setting is made so as to pass near the point 17.

  In the example of FIG. 3, the virtual line 18 is a straight line, but the present invention is not limited to this. For example, the virtual line 18 may be an arc centered on the array center 19. In this case, the positions of the reception focal points Fx_1 to Fx_4 are set so that the distance from the array center 19 to each reception focus and the distance from the array center 19 to the reference point 17 are equal. Even if the virtual line 18 is a straight line, in practice, the distance from the array center 19 to each reception focus and the distance from the array center 19 to the reference point 17 can be regarded as equal.

  Thereafter, the setting unit 5 outputs the coordinates of the reception focal points Fx_1 to Fx_4 and the coordinates of the reference point 17 to each first delay addition circuit 11 constituting the first delay addition unit 3. Thereby, each first delay adder circuit 11 calculates a delay time for each transducer 1 connected by the signal line 13.

  Specifically, the first delay addition circuit 11 calculates the propagation time to the reference point 17 and the propagation time to the reception focal points Fx_1 to Fx_4 for each connected transducer 1. Further, the first delay adding circuit 11 calculates the difference between the propagation time to the reception focal point and the propagation time to the reference point 17 for each of the reception focal points Fx_1 to Fx_4 for each connected transducer 1. The bias data is added to the difference to obtain a positive value. The value obtained in this way is the delay time.

  Further, each first delay adder circuit 11 performs delay processing on the signal detected by the transducer 1 using the calculated delay time, and further performs phase addition of the delayed signal to perform addition processing.

  FIG. 4 is a perspective view showing a reception focal point set for delay addition processing by the second delay addition unit of the ultrasonic diagnostic apparatus according to Embodiment 1. FIG. 5 is an enlarged view of the virtual axis and the transducer shown in FIG.

  As shown in FIG. 4, in addition to the points shown in FIG. 3, the setting unit 5 also sets the reception focal points Fy_1 to Fy_4 of the plurality of reception beams formed by the second delay addition unit 4 and the virtual axis 21. Do. The setting unit 5 sets the reception focal points Fy_1 to Fy_4 so that the virtual line 20 passing through the reception focal points Fy_1 to Fy_4 intersects the transmission sound ray axis 16 and is perpendicular to the x direction.

  Note that the second delay adder 4 performs a delay addition process on the signal delayed and added by the first delay adder 3. For this reason, the reception focal points Fy_1 to Fy_4 are not actual reception focal points of the reception beam but virtual reception focal points (virtual reception focal points). This point will be described later.

  Also in the example of FIG. 4, the setting unit 5 is configured such that the arrangement of the reception focal points Fy_1 to Fy_4 is line symmetric with respect to the transmission sound ray axis 16, and the line connecting the reception focal points Fy_2 and Fy_3 is the reference point on the transmission sound ray axis 16 Setting is made so as to pass in the vicinity of 17.

  In the example of FIG. 4, the virtual line 20 is a straight line as in the example of FIG. 3, but the present invention is not limited to this. For example, the virtual line 20 may also be an arc centered on the array center 19. In this case, the positions of the reception focal points Fy_1 to Fy_4 are also set so that the distance from the array center 19 to each reception focus and the distance from the array center 19 to the reference point 17 are equal. Even if the virtual line 20 is a straight line, in practice, the distance from the array center 19 to each reception focus and the distance from the array center 19 to the reference point 17 can be regarded as equal.

  The setting unit 5 sets the virtual axis (y ′ axis) 21 so as to be parallel to the y direction through the intersection (array center 19) between the transmission sound ray axis 26 and the transmission / reception wave surface of the probe 2. Further, as shown in FIG. 5, after setting the virtual axis 21, the setting unit 5 connects the center 22 of each of the plurality of transducers 1 adjacent to the virtual axis 21 and the virtual axis 21 with the shortest line segment 24. A plurality of intersections 23 between the line segment 24 and the virtual axis 21 are obtained. When the virtual axis 21 passes over the transducer 1, the setting unit 5 obtains an intersection point for the transducer 1 through which the virtual axis 21 passes.

  Thereafter, the setting unit 5 uses the coordinates of the reception focal points Fy_1 to Fy_4, the coordinates of the reference point 17, and the coordinates of the plurality of intersections 23 to each second delay addition circuit 12 that constitutes the second delay addition unit 4. Output to. Thereby, each second delay addition circuit 12 calculates a delay time and performs a delay addition process.

  Hereinafter, the calculation of the delay time by the second delay adder circuit 12 will be described with reference to FIG. FIG. 6 is a block diagram showing a circuit configuration of a second delay addition circuit constituting the second delay addition unit. In FIG. 6, only a part of the second delay addition circuit 12 is shown. In the following description, FIGS. 2, 4 and 5 are referred to as appropriate.

  As shown in FIG. 6, the second delay addition circuit 12 (see FIG. 2) includes a propagation time calculation circuit 25, a reference propagation time calculation circuit 26, a subtraction circuit 27, and an addition circuit 28. The propagation time calculation circuit 25 receives the coordinates of the reception focal points Fy_1 to Fy_4 output from the setting unit 5 and the coordinates of a plurality of intersections 23 on the virtual axis 21. The propagation time calculation circuit 25 calculates the propagation time (focus propagation time) of the ultrasonic wave from each intersection 23 to each of the reception focal points Fy_1 to Fy_4 based on the input coordinates. The propagation time calculation circuit 25 outputs the calculated focal propagation time to the subtraction circuit 27.

  The reference propagation time calculation circuit 26 receives the coordinates of the reference point 17 and the coordinates of a plurality of intersection points 23 on the virtual axis 21 output from the setting unit 5. The reference propagation time calculation circuit 26 calculates the propagation time of ultrasonic waves (reference propagation time) from each intersection 23 to the reference point 17. The reference propagation time calculation circuit 26 outputs the calculated reference propagation time to the subtraction circuit 27.

  The subtraction circuit 27 calculates the difference from the reference propagation time for each intersection 23 for all the focal propagation times calculated by the propagation time calculation circuit 25. Further, the subtraction circuit 27 outputs the difference between the calculated focal propagation time and the reference propagation time to the addition circuit 28. The adder circuit 28 adds bias data to the inputted difference to obtain a positive value, and outputs the obtained value as a delay time. Thereafter, the second delay addition circuit 12 performs a delay addition process using the delay time output from the addition circuit 28.

  FIG. 7 is a diagram showing an example of the output of the subtraction circuit 8 shown in FIG. In FIG. 7, the horizontal axis indicates the input channel numbers 1 to 16 of the second delay addition circuit 12 constituting the second delay addition unit 4. The vertical axis represents the output (delay time) of the subtraction circuit 8 shown in FIG. Each output shown in FIG. 7 corresponds to the case of the focal coordinates Fy_1 to Fy_4.

  As shown in FIG. 7, in the output of the subtraction circuit 8, the value in Fy_1 and the value in Fy_4 are in a relationship in which the signs are inverted. Similarly, the value in Fy_2 and the value in Fy_3 are in a relationship in which the signs are inverted. Furthermore, as shown in FIG. 7, for example, by multiplying the value in Fy_1 by 1/3, the value in Fy_2 when the input channels are the same can be obtained approximately. Similarly, if the value in Fy_4 is multiplied by 1/3, the value in Fy_3 when the input channels are the same can be obtained approximately.

  In addition, as described above, the second delay addition circuit 12 included in the second delay addition unit 4 performs addition processing on the signal subjected to the delay addition processing by the first delay addition unit 3, so The received beam formed by the delay adder 3 is divided. In the first embodiment, the reception beam formed by the first delay adder 3 is divided into four and deflected in four directions of minute angles. Specifically, as shown in FIG. 8, the position of the reception focal point 29 of the finally formed reception beam is a position deflected from the reception focal points Fx_1 to Fx_4 and Fy_1 to Fy_4.

  Thus, in the first embodiment, the number of reception beams formed by the second delay adder 4 is 16 (4 × 4). That is, as a result, in the ultrasonic diagnostic apparatus according to the present embodiment, a 4 × 4 two-dimensional delay addition output is obtained by the first delay addition unit 3 and the second delay addition unit 4.

  As described above, according to the ultrasonic diagnostic apparatus in the first embodiment, the delay time can be easily calculated in the subsequent delay addition process by the second delay addition unit 4. Therefore, the time required for the delay addition process by the second delay adder 4 can be shortened.

(Embodiment 2)
Next, an ultrasonic diagnostic apparatus according to Embodiment 2 of the present invention will be described with reference to FIG. The ultrasonic diagnostic apparatus according to the second embodiment is configured in the same manner as the ultrasonic diagnostic apparatus according to the first embodiment, except that the configuration of the second delay addition circuit constituting the second delay addition unit is different. . FIG. 9 is a block diagram showing a circuit configuration of a second delay addition circuit constituting the second delay addition unit of the ultrasonic diagnostic apparatus according to the second embodiment.

  9 shows only a part of the second delay adder circuit as in FIG. Further, in FIG. 9, the parts denoted by the reference numerals used in FIG. 6 are the same parts as the parts denoted by the same reference numerals in FIG. 6. Further, in the following description, FIGS. 4 and 5 are referred to as appropriate.

  As shown in FIG. 9, in the second embodiment, the second delay addition circuit includes a memory (storage means) 32 instead of including a reference propagation time calculation circuit (see FIG. 6). Further, the coordinates of the reception focal points Fy_1 to Fy_4 (see FIG. 4), the coordinates of a plurality of intersections 23 (see FIG. 5) on the virtual axis 21, and the reference point, which are output from the setting unit 5 to the propagation time calculation circuit 31. 17 coordinates (see FIG. 4) are input.

  The propagation time calculation circuit 31 first calculates the ultrasonic propagation time (reference propagation time) from each intersection 23 to the reference point 17. The propagation time calculation circuit 31 outputs the calculated reference propagation time to the memory 32 and stores it. Next, the propagation time calculation circuit 31 calculates the propagation time (focus propagation time) of the ultrasonic wave from each intersection 23 to each of the reception focal points Fy_1 to Fy_4 for each intersection 23. The propagation time calculation circuit 31 outputs the calculated focal propagation time to the subtraction circuit 27.

  The subtraction circuit 27 reads the reference propagation time stored in the memory 32, and calculates the difference from the reference propagation time for every intersection 23 for all the focal propagation times calculated by the propagation time calculation circuit 31. Further, the subtraction circuit 27 outputs the difference between the calculated focal propagation time and the reference propagation time to the addition circuit 28. The adder circuit 28 adds bias data to the inputted difference to obtain a positive value, and outputs the obtained value as a delay time. Thereafter, as in the first embodiment, also in the second embodiment, the second delay addition circuit performs a delay addition process using the delay time output from the addition circuit 28.

  As described above, in the ultrasonic diagnostic apparatus according to the second embodiment, the second delay addition circuit includes a memory instead of the reference propagation time calculation circuit. Therefore, according to the ultrasonic diagnostic apparatus in the second embodiment, the configuration of the second delay addition circuit can be simplified as compared with the first embodiment, and the cost of the ultrasonic diagnostic apparatus can be reduced and the processing speed can be improved. Can be achieved.

  Also, in the ultrasonic diagnostic apparatus according to the second embodiment, as in the ultrasonic diagnostic apparatus according to the first embodiment, the delay time is reduced in the delay addition processing in the subsequent stage by the second delay addition unit as compared with the conventional one. It can be calculated easily. Therefore, the time required for the delay addition process by the second delay addition unit can be shortened.

(Embodiment 3)
Next, an ultrasonic diagnostic apparatus according to Embodiment 3 of the present invention will be described with reference to FIG. FIG. 10 is a block diagram showing a circuit configuration of a second delay addition circuit constituting the second delay addition unit of the ultrasonic diagnostic apparatus according to the third embodiment.

  10 also shows only a part of the second delay adder circuit, as in FIG. Further, in FIG. 10, the parts denoted by the reference numerals used in FIG. 9 are the same as the parts denoted by the same reference numerals in FIG. 9. Further, in the following description, FIGS. 4 and 5 are referred to as appropriate.

  As shown in FIG. 10, in the ultrasonic diagnostic apparatus according to the third embodiment, the second delay addition circuit constituting the second delay addition unit includes a code conversion circuit 33. Other than this, the configuration is the same as that of the ultrasonic diagnostic apparatus according to the second embodiment.

  In the third embodiment, the difference between the focal propagation time calculated by the subtraction circuit 27 and the reference propagation time is output to the code conversion circuit 33. When the difference is calculated for one of the reception focal points (for example, Fy_1 and Fy_4, or Fy_2 and Fy_3) having a line-symmetrical positional relationship with each other, the code conversion circuit 33 calculates the sign of the calculated difference. Invert and calculate the difference for the other virtual reception focus.

  Specifically, as shown in FIG. 7 in the first embodiment, the value in Fy_1 and the value in Fy_4 are in a relationship in which signs are inverted. Therefore, when the difference with respect to the reception focal point Fy_1 is output, the code conversion circuit 33 outputs the output value to the adder circuit 28 without converting the code, and converts the output value code. The obtained value is output to the adding circuit 28 as the value of the reception focal point Fy_4.

  Similarly, as can be seen from FIG. 7, the value in Fy_2 and the value in Fy_3 are also in a relationship in which the signs are inverted. Therefore, when the difference with respect to the reception focal point Fy_2 is output, the code conversion circuit 33 outputs the value of the output value to the addition circuit 28 without converting it, and converts the code of the output value. The obtained value is output to the adding circuit 28 as the value of the reception focal point Fy_3.

  The adder circuit 28 adds bias data to the inputted difference to obtain a positive value, and outputs the obtained value as a delay time. Thereafter, similarly to the first embodiment, also in the third embodiment, the second delay addition circuit performs a delay addition process using the delay time output from the addition circuit 28.

  As described above, in the ultrasonic diagnostic apparatus according to the third embodiment, since the second delay addition circuit includes the code conversion circuit 33, the second delay addition circuit performs as compared with the first and second embodiments. The number of arithmetic processes can be reduced. For this reason, according to the ultrasonic diagnostic apparatus in the third embodiment, the processing speed can be further improved as compared with the first and second embodiments.

  Also, in the ultrasonic diagnostic apparatus according to the third embodiment, similarly to the ultrasonic diagnostic apparatus according to the first embodiment, the delay time is set in the delay addition process in the subsequent stage by the second delay addition unit as compared with the conventional one. It can be calculated easily. Therefore, the time required for the delay addition process by the second delay addition unit can be shortened.

(Embodiment 4)
Next, an ultrasonic diagnostic apparatus according to Embodiment 4 of the present invention will be described with reference to FIG. FIG. 11 is a block diagram showing a circuit configuration of a second delay addition circuit constituting the second delay addition unit of the ultrasonic diagnostic apparatus according to the fourth embodiment.

  11 also shows only a part of the second delay adder circuit, as in FIG. Further, in FIG. 11, the parts denoted by the reference numerals used in FIG. 9 are the same as the parts denoted by the same reference numerals in FIG. 9. Further, in the following description, FIGS. 4 and 5 are referred to as appropriate.

  As shown in FIG. 11, in the ultrasonic diagnostic apparatus according to the fourth embodiment, the second delay addition circuit constituting the second delay addition unit includes a multiplication circuit 34. Other than this, the configuration is the same as that of the ultrasonic diagnostic apparatus according to the second embodiment.

  In the fourth embodiment, the difference between the focal propagation time calculated by the subtraction circuit 27 and the reference propagation time is output to the multiplication circuit 34. When the difference between the focal propagation time and the reference propagation time is calculated for at least one of the reception focal points Fy_1 to Fy_4, the multiplication circuit 34 multiplies the calculated difference by a preset constant to The difference with respect to the reception focus is calculated.

  Specifically, as shown in FIG. 7 in the first embodiment, by multiplying the value in Fy_1 by 1/3, the value in Fy_2 when the input channels are the same can be obtained approximately. Therefore, when the difference with respect to the reception focal point Fy_1 is output, the multiplication circuit 34 outputs the output value as it is to the addition circuit 28 and multiplies the output value by a constant (1/3). The obtained value is output to the adding circuit 28 as the value of the reception focal point Fy_2.

  Similarly, as can be seen from FIG. 7, by multiplying the value in Fy_4 by 1/3, the value in Fy_3 when the input channels are the same can be obtained approximately. Therefore, when the difference about the reception focal point Fy_4 is output, the multiplication circuit 34 outputs the output value as it is to the addition circuit 28 and multiplies the output value by a constant (1/3). The obtained value is output to the adding circuit 28 as the value of the reception focal point Fy_3.

  The adder circuit 28 adds bias data to the inputted difference to obtain a positive value, and outputs the obtained value as a delay time. Thereafter, similarly to the first embodiment, also in the fourth embodiment, the second delay addition circuit performs a delay addition process using the delay time output from the addition circuit 28.

  As described above, in the ultrasonic diagnostic apparatus according to the fourth embodiment, the multiplication circuit 34 is provided in the second delay addition circuit. For this reason, also in the fourth embodiment, as in the third embodiment, the number of arithmetic processes performed by the second delay adder circuit can be reduced as compared with the first and second embodiments. For this reason, also in the ultrasonic diagnostic apparatus according to the fourth embodiment, the processing speed can be further improved as compared with the first and second embodiments.

  Also, in the ultrasonic diagnostic apparatus according to the fourth embodiment, similarly to the ultrasonic diagnostic apparatus according to the first embodiment, the delay time is set in the delay addition process in the subsequent stage by the second delay addition unit as compared with the conventional one. It can be calculated easily. Therefore, the time required for the delay addition process by the second delay addition unit can be shortened.

(Embodiment 5)
Next, an ultrasonic diagnostic apparatus according to Embodiment 5 of the present invention will be described with reference to FIGS. FIG. 12 is a perspective view showing a probe of the ultrasonic diagnostic apparatus in the fifth embodiment. FIG. 13 is a block diagram illustrating the configuration of the probe and the first delay adder of the ultrasonic diagnostic apparatus according to the fifth embodiment. In FIG. 12, the parts denoted by the reference numerals used in FIGS. 3 and 4 are the same as the parts denoted by the same reference numerals in FIGS. 3 and 4.

  As shown in FIG. 12, also in the fifth embodiment, as in the first embodiment, the probe 2 is configured by arranging a plurality of transducers 1 in a matrix along the x and y directions. Yes. Also, the ultrasonic diagnostic apparatus in the fifth embodiment is similar to the ultrasonic diagnostic apparatus in the first embodiment in that the first delay adding unit, the second delay adding unit, the setting unit, the image processing unit, and the display Part (see FIG. 1).

  However, as shown in FIG. 12, in the fifth embodiment, unlike the first embodiment, the plurality of transducers 1 are grouped into a plurality of groups 35. Each group 35 is composed of adjacent transducers 1, and the plurality of groups 35 are arranged in a matrix along the x and y directions. In the example of FIG. 12, each group 34 includes four adjacent transducers 1.

  As shown in FIG. 13, the ultrasonic diagnostic apparatus according to the fifth embodiment includes a plurality of phasing adders 36 for each group 35. The phasing adder 36 performs phasing addition on the signals detected by the transducers (P1 to P4) 1 constituting the corresponding group, and outputs the phasing addition signal to the first delay addition circuit 11.

  In the example of FIG. 13, the phasing adder 36 is provided in the probe handle 37 that the operator of the ultrasonic diagnostic apparatus holds and operates because the circuit scale is small. The probe handle 37 is also provided with a probe 2.

  For this reason, in the first embodiment, the first delay addition circuit 11 performs a delay addition process on the signal output from the phasing addition unit 36. The setting unit (see FIG. 1) sets the virtual axis 21 (y ′ axis) as in the first embodiment. However, the setting unit connects the center 38 of each of the plurality of groups 35 adjacent to the virtual axis 21 and the virtual axis 21 with the shortest line segment through the virtual axis 21 and the virtual axis 21. Are obtained. Further, the second delay adder 4 calculates the focal propagation time and the reference propagation time for each intersection 39.

  The ultrasonic diagnostic apparatus according to the fifth embodiment is configured in the same manner as the ultrasonic diagnostic apparatus according to the first embodiment and functions in the same manner except for the points described above. That is, also in the fifth embodiment, the reception focal points Fx_1 to Fx_4 (see FIG. 3) and Fy_1 to Fy_4 (see FIG. 4) are set by the setting unit. The first delay addition unit (first delay addition circuit 11) and the second delay addition unit (second delay addition circuit) perform a delay addition process based on these reception focal points.

  As described above, in the fifth embodiment, since the transducers 1 are grouped, the number of signal lines 13 that connect the probe 2 and the first delay addition unit (first delay addition circuit 11) is determined. This can be reduced as compared with the first embodiment. Therefore, if the ultrasonic diagnostic apparatus according to the fifth embodiment is used, the number of circuits constituting the first delay addition circuit 11 can be reduced, so that the chip area can be reduced. For this reason, it is possible to easily increase the density of the chips that function as the first delay adder and the second delay adder.

  As described above, according to the ultrasonic diagnostic apparatus of the present invention, it is possible to shorten the time required for the delay addition process at the subsequent stage. For this reason, the ultrasonic diagnostic apparatus according to the present invention is useful when a subject is scanned three-dimensionally to display a three-dimensional image.

1 is a block diagram schematically showing an overall configuration of an ultrasonic diagnostic apparatus according to Embodiment 1. FIG. The perspective view which shows the structure of the probe of the ultrasonic diagnosing device in Embodiment 1, and a delay addition part. The perspective view which shows the receiving focus set for the delay addition process by the 1st delay addition part of the ultrasound diagnosing device in Embodiment 1 The perspective view which shows the receiving focus set for the delay addition process by the 2nd delay addition part of the ultrasound diagnosing device in Embodiment 1 The figure which expands and shows the virtual axis | shaft and transducer which are shown in FIG. The block diagram which shows the circuit structure of the 2nd delay addition circuit which comprises a 2nd delay addition part. The figure which shows an example of the output of the subtraction circuit 8 shown in FIG. Figure showing contrast between virtual reception focus and actual reception focus The block diagram which shows the circuit structure of the 2nd delay addition circuit which comprises the 2nd delay addition part of the ultrasound diagnosing device in Embodiment 2. FIG. The block diagram which shows the circuit structure of the 2nd delay addition circuit which comprises the 2nd delay addition part of the ultrasonic diagnosing device in Embodiment 3. FIG. The block diagram which shows the circuit structure of the 2nd delay addition circuit which comprises the 2nd delay addition part of the ultrasonic diagnosing device in Embodiment 4. FIG. The perspective view which shows the probe of the ultrasonic diagnosing device in Embodiment 5. FIG. 7 is a block diagram showing the configuration of the probe and the first delay adder of the ultrasonic diagnostic apparatus in the fifth embodiment. Configuration diagram showing schematic configuration of conventional ultrasonic diagnostic apparatus

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Transducer 2 Probe 3 1st delay addition part 4 2nd delay addition part 5 Setting part 6 Transmission pulse generation part 7 Image processing part 8 Display part 9 Ultrasonic beam 10 Reception beam 11 1st delay addition circuit 12 Second delay addition circuit 13, 14, 15 Signal line 16 Transmission sound ray axis 17 Reference point 18, 20 Virtual line passing through reception focus 19 Arrangement center 21 Virtual axis 22 Transducer center 23 Intersection 24 Transducer center and virtual axis Shortest line segment 25, 31 Propagation time computation circuit 26 Reference propagation time computation circuit 27 Subtraction circuit 28 Addition circuit 29 Reception focus of reception beam finally formed 32 Memory 33 Code conversion circuit 34 Multiplication circuit 35 Group 36 Phase adjustment Adder 37 Probe handle 38 Center of group 39 Center of group and virtual axis are connected in the shortest distance Intersection point on virtual axis of line segment Fx_1 to Fx_4, Fy_1 to Fy_4 Reception focus

Claims (7)

A probe having a plurality of transducers arranged in a matrix along a first direction and a second direction orthogonal to each other, and performing delay addition processing on the signals detected by each of the plurality of transducers, A first delay adder that forms a plurality of receive beams arranged along the first direction; and a signal that has been subjected to a delay addition process by the first delay adder; An ultrasonic diagnostic apparatus comprising: a second delay addition unit that forms a plurality of reception beams arranged in a second direction;
A reference point located on the transmission sound ray axis of the ultrasonic beam, a plurality of virtual reception focal points for forming a plurality of reception beams arranged in the second direction by the second delay adder, and the transmission A virtual axis passing through the intersection of the sound ray axis and the transducer transmission / reception surface and parallel to the second direction is set, and each of the plurality of transducers through which the virtual axis passes or is adjacent to the virtual axis Further comprising a setting unit for obtaining a plurality of intersections between the line segment and the virtual axis when connecting the center and the virtual axis with the shortest line segment;
The plurality of virtual reception focal points are set so that a virtual line passing through all virtual reception focal points intersects the transmission sound ray axis and is perpendicular to the first direction,
The second delay adder includes, for each of the plurality of intersections, a propagation time from the intersection to a reference point set on the transmission sound ray axis, and a propagation time from the intersection to each of the plurality of virtual reception focal points. The difference between the propagation time to each of the plurality of reception focal points and the propagation time to the reference point is calculated, and the delay addition process is performed using the calculated difference. Ultrasonic diagnostic equipment. The intersection of the transmission sound ray axis and the wave transmitting / receiving surface of the probe is located at the array center of the plurality of transducers,
2. The position of the plurality of virtual reception focal points is set such that a distance from the array center to each of the plurality of virtual reception focal points is equal to a distance from the array center to the reference point. Ultrasound diagnostic equipment.   A first propagation time calculation circuit that calculates a propagation time to the reference point; a second propagation time calculation circuit that calculates a propagation time to each of the plurality of virtual reception focal points; The ultrasonic diagnostic apparatus according to claim 1, further comprising: a subtracting circuit that calculates the difference.   A propagation time calculation circuit for calculating a propagation time to the reference point or a propagation time to each of the plurality of virtual reception focal points; a propagation time to the reference point; and the plurality of virtual receptions. Storage means for storing one of the propagation times up to each focal point; and a subtracting circuit for calculating the difference from the one propagation time stored in the storage means and the other propagation time. The ultrasonic diagnostic apparatus according to claim 1. The arrangement of the plurality of virtual reception focal points is set to be line symmetric with respect to the transmission sound ray axis,
The second delay addition unit further includes a sign inversion circuit,
The sign inversion circuit reverses the sign of the calculated difference when the difference is calculated for one virtual reception focus among a pair of virtual reception focal points that are in a line-symmetrical positional relationship with each other. The ultrasonic diagnostic apparatus according to claim 1, wherein the difference with respect to the reception focus is calculated. The second delay addition unit further includes a multiplication circuit,
The multiplier circuit, when the difference is calculated for at least one of the plurality of virtual reception focal points, multiplies the calculated difference by a preset constant to thereby calculate the difference for the other virtual reception focal points. The ultrasonic diagnostic apparatus according to any one of claims 1 to 4, which calculates: The plurality of transducers are grouped into a plurality of groups, and each group is composed of adjacent transducers such that the arrangement of the plurality of groups is in a matrix along the first direction and the second direction. And
Further, a plurality of phasing adders are provided for each group, and the phasing adder phasing-adds the signals detected by the transducers constituting the corresponding group, and this is added to the first delay addition. Output to
The first delay addition unit performs a delay addition process on the signal output from the phasing addition unit,
When the setting unit connects the center of each of a plurality of groups that the virtual axis passes or is adjacent to the virtual axis and the virtual axis by the shortest line segment, a plurality of the line segment and the virtual axis The ultrasonic diagnostic apparatus according to claim 1, wherein an intersection point is obtained.

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