JP2001198122A - Two-dimensional array type ultrasonic probe and ultrasonograph - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize two-dimensional scan by high SN in a two-dimensional array type ultrasonic probe corresponding to volume scan (thinning scan). SOLUTION: This two-dimensional array type ultrasonic probe 1 is constituted by arranging a vibrator unit 3 having a plurality of vibration elements 6 arrayed in a matrix shape, a connecting part 7 for drawing electrodes of the vibration elements 6 to a rear side and a plurality of electronic circuit boards 8 in front of the body of an equipment 2. Partial vibration elements 6 in the plurality of vibration elements 6 are characterized by being connected in common by prescribed numbers within the electronic circuit boards 8.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic probe for converting an electric signal / ultrasonic signal between a subject and an ultrasonic diagnostic apparatus main body, and more particularly, to a two-dimensionally arranged vibrating element. The present invention relates to a two-dimensional array type ultrasonic probe.

[0002]

2. Description of the Related Art In addition to a conventional two-dimensional tomographic image, a one-dimensional array type ultrasonic probe is manually or mechanically swung in a direction orthogonal to a slice plane, or by rotating the probe about its axis. , A volume scan (also referred to as a three-dimensional scan) to generate a tomographic image of an arbitrary section from the volume data, display a blood vessel three-dimensionally,
Various data collection and display methods have been devised, such as displaying a surface image of a fetus and the like in three dimensions.

However, moving the one-dimensional array type ultrasonic probe mechanically or manually requires a long time for data collection, and it is actually difficult to obtain a moving image in real time. there were.

[0004] In recent years, with the progress of manufacturing technology, a small two-dimensional array type ultrasonic probe in which vibrating elements are two-dimensionally arranged has been developed and studied for practical use. By electronically scanning the two-dimensional array, the ultrasonic beam can be transmitted and received three-dimensionally in any direction,
In principle, this makes it possible to collect volume data in real time.

However, if the two-dimensional array is constituted by, for example, 64 elements × 64 elements, the number of elements is as large as 4096. If one general element constitutes one channel, the number of channels is
It becomes 4096 channels.

In order to transmit and receive ultrasonic waves using all of the 4096 channels, it is necessary to increase the number of signal lines of the cable, the number of connector pins, and the number of ultrasonic transmitting and receiving circuits on the main body. Not a target.

Therefore, a technique called sparse array scan (thinning scan) has been developed in which 256 or 512 channels are sparsely selected from 4096 channels, and a volume scan is electronically performed using only the selected sparse channels. Was.

However, in this thinning scan, for example, if 4096 elements are thinned out to 512 elements (elements used in this thinning scan (volume scan) are called sparse elements), compared with the case where all 4096 elements are used, Therefore, there is a disadvantage that the sensitivity is reduced to 512/4096 = 0.125 times. Therefore, there is a problem that the SN is reduced.

Therefore, as a general use, only a rough diagnosis is performed, such as identifying the position and range of a site of interest using a volume scan with a low SN.
After that, a one-dimensional array type ultrasonic probe for two-dimensional scanning having a high SN is replaced, and a detailed diagnosis with high accuracy is performed.

[0010]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a two-dimensional array type ultrasonic probe corresponding to a volume scan (thinning-out scan) and to realize a two-dimensional scan at a high SN.

[0011]

According to the present invention, there is provided a vibrator unit having a plurality of vibrating elements arranged in a matrix, a connecting portion for drawing electrodes of the vibrating elements backward, and a plurality of circuit boards. However, in the two-dimensional array type ultrasonic probe arranged in the housing, a part of the plurality of vibration elements is commonly connected in a predetermined number in the circuit board. I do.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A two-dimensional array type ultrasonic probe according to the present invention will be described below in detail with reference to the drawings. FIG. 1 shows the appearance of a two-dimensional array type ultrasonic probe according to the present embodiment. A transducer unit 3 is accommodated in the front of the inside of the housing 2 of the two-dimensional array type ultrasonic probe 1. This vibrator unit 3
Is connected to the ultrasonic diagnostic apparatus main body via the cable 4.

As shown in FIG. 2, the cable 4 includes a plurality of transmission-only cable lines 9 ', a plurality of reception-only cable lines 10', and a transmission / reception-use cable line 11 '. The transmission cable 9 'is connected to a transmission circuit 31 for generating a transmission pulse, and the reception cable 10' is connected to a reception circuit 32 for generating a reception signal mainly by digital beamform.
1 'is a transmission circuit 3 for two-dimensional scan and three-dimensional scan at the time of transmission and at the time of reception via the transmission / reception switch 33.
1 and the receiving circuit 32 are selectively connected. When a plurality of transducers are connected, the load conditions are different. Therefore, as shown in FIG. 3, the transmission / reception cable line 11 'is connected to a transmission circuit 31' dedicated to two-dimensional scanning and three-dimensional scanning.
And the receiving circuit 32 '. The B-mode processing unit 34 generates B-mode image data representing the morphological information of the tissue based on the amplitude of the received signal. The color flow mapping mode processing unit (CFM) 35 generates color flow mapping image data representing the distribution of the velocity value, power value, and variance value of the blood flow and the like based on the Doppler shift amount included in the received signal. The image processing unit 36 processes the B-mode image data and the color flow mapping image data. The monitor 40 displays a B-mode image or a color flow mapping image based on the image data processed by the image processing unit 36.

FIG. 4 shows the components of the vibrator unit 3. The vibrator unit 3 includes a two-dimensional array vibrator 5 in which a plurality of vibrating elements 6 are arranged in a matrix.
And a connection portion 7 for individually pulling out the electrodes of the vibration element 5 rearward, and a plurality of electronic circuit boards 8 on which a wiring pattern, a switching element, an amplification element, and the like are formed. Although not shown, the two-dimensional array type ultrasonic probe 1 is also provided with other general components such as an acoustic lens, an acoustic preparation layer, and a backing material. In the following description, one vibrating element 6 constitutes one channel, but two or more neighboring vibrating elements 6 may constitute one channel.

The two-dimensional array vibrator 5 has, for example, 64 vibrating elements 6 arranged in the X direction (column direction) and 64 vibrating elements 6 arranged in the Y direction (row direction).
A matrix size of 4 elements x 64 elements, for a total of 4,09
It has six elements. With this number of elements, the vibrating element 6 is set at 0.
Assuming that the two-dimensional array transducers 5 are arranged at a pitch of 3 mm, the detection surface of the two-dimensional array transducer 5 has a size of about 20 mm × 20 mm in outer shape.

Each of the vibrating elements 6 is composed of a piezoelectric element, a common electrode formed on the front surface thereof, and an individual electrode formed on the back surface thereof. The number of the common electrodes is one, and the individual electrodes are individually drawn out to the electronic circuit board 8 in the two-dimensional array type ultrasonic probe via the connection part 7 individually.
On the surface of each electronic circuit board 8, a two-dimensional array vibrator 5 is provided.
A wiring pattern is formed in addition to the electronic circuits for one row. The electronic circuit boards 8 are mounted on the back surface of the two-dimensional array transducer 5 in a state where a total of 64 electronic circuit boards 8 are stacked. Note that a circuit for one row of the two-dimensional array vibrator 5 may be formed on each of the front and back surfaces of each of the electronic circuit boards 8. In this case, a total of 32 electronic circuit boards 8 are provided. The two-dimensional array vibrator 5 is mounted on the back surface in a superposed state.

FIG. 5 schematically shows wiring corresponding to one row (64 elements (64 channels)) of the two-dimensional array vibrator 5 in the electronic circuit board 8.
Of course, the wiring in the other columns is the same as in FIG. 6 for one row
Sixteen discrete channels selected at a rate of one in four out of the four elements 6 are connected to transmission-only lines 9 in the electronic circuit board 8 as transmission-only elements during volume scanning (thinning-out scanning). You. The transmission line 9 is connected to a transmission cable 9 ′, the reception line 10 is connected to a reception cable 10 ′, and the common connection line 11 is connected.
Is connected to the transmission / reception cable line 11 '.

Similarly, 4 out of 64 elements 6 in one row
16 discrete elements 6 selected at a rate of 1
It is connected to a reception-only line 10 in the electronic circuit board 8 as a reception-only element in a volume scan (thinning-out scan). Generally, the transmission-only element and the reception-only element are arranged in a regular array pattern in a two-dimensional plane or in a random array pattern for each of transmission and reception.

At the time of volume scanning, at the time of transmission, 16 elements dedicated to transmission × 64 columns totaling 1,02
Ultrasound is transmitted via four elements, while on reception,
The echo is received via a total of 1,024 elements 6 for 16 elements × 64 columns dedicated to reception.

Note that a total of 32 elements 6 for transmission and reception are used.
Is divided into a dedicated transmission line 9 and a dedicated reception line 10 and connected,
It is not limited to separately providing the 16 transmission-only elements 6 and the 16 reception-only elements 6, and a total of 32 or half of the 16 elements 6 is provided by 32 or 16 transmission / reception lines 11. And 32 or 16 elements 6 may be used for both transmission and reception, or only a part of the total 32 elements 6 for transmission and reception may be used for transmission and reception. Alternatively, the remaining elements 6 may be assigned half each for transmission only and reception only. Furthermore, the number of transmission-only elements 6 and the number of reception-only elements 6 are not limited to being the same, and may be different.

As shown in FIG. 5, the dedicated reception line 10 includes
A buffer circuit 12 is provided to reduce a loss in a transmission system such as the cable 4. The buffer circuit 12 can be omitted if the element impedance can be reduced to a negligible level by, for example, configuring the vibration element 6 as a laminated type, and the loss of the transmission system such as the cable 4 can be ignored. It is.

As described above, in the volume scan,
Although 32 elements 6 out of 64 elements 6 are used for transmission and reception in each column, the remaining 32 elements 6 in each column are commonly connected by a predetermined number to a common connection line 11 for both transmission and reception. .
FIG. 5 shows an example in which, out of the 32 elements 6, neighboring 8 channels are commonly connected.

At the time of two-dimensional scanning, 32 elements 6 connected in common are used, and 3 elements 6 connected in common are used.
By using 16 transmission-only elements 6 and 16 reception-only elements 6 together with the two elements 6, it is possible to improve transmission / reception sensitivity and SN with an increase in the number of channels.

As shown in FIG. 6, it is also possible to commonly connect 16 neighboring elements out of 32 elements 6 per row of the common connection object, and as shown in FIG.
All of the 32 elements 6 may be commonly connected to one common connection line 11.

As shown in FIG. 8, only the central 16 elements 6 of the 32 elements 6 are subjected to common connection, and eight adjacent elements are commonly connected. As shown in FIG.
All the elements 6 are connected in common to one common connection line 11
May be pulled out. Thus, the central element 6
Only the common connection allows the ultrasonic beam to be substantially thinned. This beam thinning is more effective if an acoustic lens that focuses the beam in the slice direction at a predetermined distance is attached to the front surface of the transducer 5 during two-dimensional scanning.

In order to realize the same effect as that of the acoustic lens, as shown in FIG. 10, the delay time of each of the commonly connected vibrating elements 6 becomes longer toward the center in the electronic circuit board 8. Alternatively, a delay element 13 whose delay time is adjusted to be shorter toward the outside may be provided. This delay element 13
If a variable delay time type is adopted, the depth of focus can be arbitrarily changed. These delay elements 13
In addition to a general inductance delay line, a CCD using a CCD operating in a charge region, which has been studied in recent years, is advantageous in terms of size and power consumption.

Further, since the commonly connected elements 6 are not used in the volume scan, these elements 6 are connected to the changeover switch 14 provided on the common connection line 11 during the volume scan as shown in FIG. By connecting to a fixed potential of low impedance such as a ground potential or a power supply potential via the device, it is possible to effectively prevent crosstalk to the other element 6 and the cable 4 connected thereto.

Further, as shown in FIG.
Similarly to the above, a buffer 15 may be provided in the common connection line 11 in order to improve transmission characteristics at the time of reception. In this case, a high-voltage transmission pulse is transmitted to the vibrating element 6 at the time of transmission, and a diode circuit 16 that bypasses the high-voltage transmission to the buffer 15 is required in the buffer 15 in order to prevent the high voltage from being applied to the buffer 15.

With the above-described configuration, at the time of volume scanning, 16 elements 6 dedicated to transmission per row are used.
, And 16 elements 6 dedicated to reception, so-called thinning-out scanning can be performed. On the other hand, at the time of two-dimensional scanning, 32 elements 6 connected in common per column are used.
By using 16 elements 6 dedicated to transmission and 16 elements 6 dedicated to reception together with the 32 elements 6 connected in common, the transmission / reception sensitivity increases as the number of elements increases. And SN can be improved.

In some cases, the number of elements 6 used for volume scanning differs between columns. In this case, the number of commonly connected elements 6 differs between columns, and the number of elements 6 differs. This causes a problem that the transmission / reception sensitivity fluctuates between columns.However, the problem is that sensitivity correction data for correcting this uneven sensitivity distribution to a uniform sensitivity distribution is obtained by actual measurement or simulation, and the correction is performed. Sensitivity can be corrected by transmission power, reception gain, or both according to data.

In the above description, a plurality of elements 6 are commonly connected in the column (X) direction. However, similarly, a plurality of elements 6 may be commonly connected in the row (Y) direction. . Further, as shown in FIG. 12, the direction of common connection may be selectable between a column (X) and a row (Y).

FIG. 12 shows the surface structure of the connection portion 7. On this surface, 64 × 64 bumps 21 are formed, and the bumps 21 use the electrodes of the vibrating element 6 of the two-dimensional array vibrator 5. Are electrically connected to the The connection portion 7 includes a plurality of common connection lines 22 parallel to the X direction.
Are provided, and a plurality of common connection lines 21 are provided in parallel with the Y direction so as to be orthogonal to the above. In addition,
The electronic circuit board 8 is provided with a circuit for performing signal processing of the transmission line 9 and the reception line 10 for volume scanning.

Each of the common connection lines 22 has 32 elements 6 to be connected in common arranged in the same X direction.
Are connected to the disconnection switch 2
5 are connected. Similarly, each of the common connection lines 21 has 32 bumps 2 connected to 32 common connection target elements 6 arranged in the same Y direction.
1 is connected via a disconnect switch 25.

The switches 25 arranged in the X direction and the switches 25 arranged in the Y direction operate in opposite phases to each other, and when the switch 25 in the X direction (or Y direction) is in a closed state (connected state). , Y direction (X direction) switch 25 is in an open state (disconnection state). That is, the switch 25 in the X direction and the switch 25 in the Y direction can be alternately operated by a single changeover switch signal. When the switch 25 in the X direction is in a closed state, 32 elements 6 are commonly connected per row, and when the switch 25 in the Y direction is in a closed state, 32 elements 6 are commonly connected per row.

In this way, the direction of common connection is orthogonal to X
By selectively switching between the direction and the Y direction, workability during two-dimensional scanning can be improved.

FIG. 13 shows an example of a display screen when displaying a tomographic image of the subject using the two-dimensional array type ultrasonic probe according to the present embodiment. Reconstructing tomographic images of two orthogonal planes (for example, a horizontal section and a vertical section) from volume data regarding the inside of the subject obtained by the volume scan,
In addition, it is possible to reconstruct a tomographic image relating to a horizontal section at an arbitrary depth known as a so-called C mode, and to display these three types of tomographic images on the same screen. When the longitudinal section obtained by two-dimensional scanning with the vibrating elements in a one-dimensional array by common connection has the same angle as the section of the tomographic image reconstructed from the volume data obtained by volume scanning, Can be switched to display. This may be automatically switched.
Further, a cross section by the vibrating element at the time of the volume scan or a three-dimensional display image may be displayed at the same time, or one and two cross sections may be selectively extracted and displayed. Furthermore, in the embodiment in which two orthogonal cross sections can be displayed, it is also possible to simultaneously display the orthogonal two cross section image and the three-dimensional image.

The present invention is not limited to the above-described embodiments, but can be implemented in various modifications and combinations within the scope of the invention. For example, the common connection is made by the electronic circuit in the two-dimensional array type ultrasonic probe, but all the elements may be drawn out by lead wires and commonly connected in the connector of the two-dimensional array type ultrasonic probe or in the main body of the ultrasonic diagnostic apparatus. .

Although the sparse elements for volume scanning have been described as transmission-only and reception-only, if thinning, which is the purpose of sparse, is realized, the sparse elements are not limited to transmission-only and reception-only. element,
Various changes can be made, such as partial use or transmission only.

[0039]

According to the present invention, a volume scan (thinning-out scan) can be performed by using a vibration element which is not connected in common. On the other hand, not only a vibration element which is not connected in common but also a two-dimensional scan is used. Commonly connected vibrating elements can be used, and high SN can be realized. Moreover, there is no need to replace the ultrasonic probe between the volume scan and the two-dimensional scan as in the related art.

[Brief description of the drawings]

FIG. 1 is an external view of a two-dimensional array type ultrasonic probe according to an embodiment of the present invention.

FIG. 2 is a diagram showing a connection between the probe shown in FIG. 1 and an ultrasonic diagnostic apparatus main body.

FIG. 3 is a diagram showing another example of the connection between the probe of FIG. 1 and the ultrasonic diagnostic apparatus main body.

FIG. 4 is a view showing components of the vibration element unit 3 of FIG. 1;

FIG. 5 is a diagram showing a wiring example when eight channels in the circuit board of FIG. 4 are commonly connected;

FIG. 6 is a diagram showing a wiring example when 16 channels in the circuit board of FIG. 4 are commonly connected;

FIG. 7 is a diagram showing a wiring example when 32 channels are commonly connected in the circuit board of FIG. 4;

FIG. 8 is a diagram showing an example of wiring in a case where eight channels are commonly connected to the center 16 channels in the circuit board of FIG. 4;

FIG. 9 is a diagram showing a wiring example in the case where 16 central channels in the circuit board of FIG. 4 are commonly connected;

FIG. 10 is a diagram showing delay lines provided for each of the commonly connected channels in the circuit board of FIG. 4 and a ground changeover switch provided for the common connection lines.

FIG. 11 is a diagram illustrating a buffer and a diode circuit provided on a common connection line in the circuit board of FIG. 4;

FIG. 12 is a diagram showing a switch for switching a common connection direction in a row / column in the circuit board of FIG. 4;

FIG. 13 is a view showing a display example of a tomographic image of three sections generated using the two-dimensional array type ultrasonic probe according to the embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Two-dimensional array type ultrasonic probe, 2 ... Probe main body part, 3 ... Vibrating element unit, 4 ... Cable, 5 ... Two-dimensional array vibrator, 6 ... Vibrating element, 7 ... Connection part, 8 ... Electronic circuit board, 9: dedicated transmission line, 10: dedicated reception line, 11: common connection line, 12: buffer.

Claims (13)

[Claims] A vibrator unit having a plurality of vibrating elements arranged in a matrix, a connecting portion for drawing out electrodes of the vibrating elements backward, and a plurality of electronic circuit boards is arranged in a housing. In the two-dimensional array type ultrasonic probe, a part of the plurality of vibrating elements is commonly connected by a predetermined number in the electronic circuit board. Sound wave probe. 2. A vibrating element other than a part of the commonly connected vibrating elements is a vibrating element used for three-dimensional scanning, and the part of the commonly connected vibrating elements is two-dimensional scanning. 2. The two-dimensional array type ultrasonic probe according to claim 1, which is a dedicated vibration element. 3. The two-dimensional array type ultrasonic probe according to claim 1, wherein the remaining vibrating elements other than some of the commonly connected vibrating elements are individually drawn out by the electronic circuit board. 4. A part of the commonly connected vibration elements,
2. The two-dimensional array type ultrasonic probe according to claim 1, wherein the probe is set to a ground potential or a power supply potential at least during three-dimensional scanning. 5. A partially connected vibrating element,
The other vibrating elements connected to the transmission / reception line via the electronic circuit board, and the remaining vibrating elements other than the commonly connected part of the vibrating elements are individually connected to either the transmission-only line or the reception-only line. 2. The two-dimensional array type ultrasonic probe according to claim 1, wherein the two-dimensional array type ultrasonic probe is connected via a cable. 6. The two-dimensional array type ultrasonic probe according to claim 1, wherein the vibrating elements arranged in the same row are commonly connected. 7. The two-dimensional array type ultrasonic probe according to claim 1, wherein the vibrating elements arranged in the same row are commonly connected. 8. A switch function for switching between a state in which the some of the vibrating elements are commonly connected in the same row and a state in which the some of the vibrating elements are commonly connected in the same row are provided in the connection portion. The two-dimensional array type ultrasonic probe according to claim 1, wherein 9. The two-dimensional array type ultrasonic probe according to claim 1, wherein a buffer connected to the commonly connected vibrating element is provided on the circuit board. 10. A two-dimensional array type ultrasonic probe, further comprising an acoustic lens for focusing ultrasonic waves in an arrangement direction of the commonly connected vibration elements. 11. The two-dimensional array type ultrasonic probe according to claim 1, wherein delay elements are individually connected to the commonly connected vibration elements in the electronic circuit. 12. A vibrator unit having a plurality of vibrating elements arranged in a matrix, a connecting portion for drawing out electrodes of the vibrating elements backward, and a plurality of electronic circuit boards is disposed in a housing. An ultrasonic diagnostic apparatus comprising a two-dimensional array type ultrasonic probe connected via a cable to an ultrasonic diagnostic apparatus main body having a transmitting circuit, a receiving circuit, and a signal processing unit. The vibrating elements of the unit are bundled by a predetermined number in the electronic circuit board, connected to a transmitting circuit for two-dimensional scanning and a receiving circuit for two-dimensional scanning via a changeover switch, and a part of the remaining vibrator is An ultrasonic diagnostic apparatus which is individually connected to a transmission circuit for three-dimensional scanning or a transmission circuit for three-dimensional scanning. 13. A vibrator unit having a plurality of vibrating elements arranged in a two-dimensional matrix, a connecting portion for leading out electrodes of the vibrating elements, and a plurality of electronic circuit boards is disposed in a housing. A two-dimensional array type ultrasonic probe is connected via a cable to an ultrasonic diagnostic apparatus main body having a transmitting circuit, a receiving circuit, and a signal processing unit, and is arranged in a discrete and two-dimensional distribution. A cable for transmitting a signal between the vibrating element for three-dimensional scanning and the ultrasonic diagnostic apparatus main body, a connecting means for electrically connecting a plurality of vibrating elements for two-dimensional scanning in the ultrasonic probe, An ultrasonic diagnostic apparatus comprising: a vibration element connected by the connection means; and a cable for transmitting a signal between the ultrasonic diagnostic apparatus main body.