JP2002102222A - Ultrasonic diagnostic equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem of discordant distortion directions of scanned surfaces in forward scanning and backward scanning of an array transducer, via a simple structure. SOLUTION: The direction of electronic scanning using an ultrasonic beam is reversed between forward scanning and backward scanning. A ROM 42 internally stores number string data indicating an M pieces of selected element numbers for every electronic scanning position. When a counter 44 is incremented, the number string data are read out from the ROM 42 in ascending order and outputted to a multiplexer group 30 to offer electronic scanning in one direction. When the counter 44 is decremented, the number string data are read out from the ROM 42 in descending order and outputted to the multiplexer group 30 to realize electronic scanning in the other direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an ultrasonic diagnostic apparatus, and more particularly, to an ultrasonic diagnostic apparatus having an ultrasonic probe for acquiring three-dimensional echo data.

[0002]

2. Description of the Related Art When forming a three-dimensional image, an ultrasonic probe (three-dimensional probe) for acquiring three-dimensional data is used (for example, see Japanese Patent Application Laid-Open No. 3-184532). Such a three-dimensional probe has an array transducer that forms an ultrasonic beam to be electronically scanned, and the array transducer is mechanically scanned in parallel or rocking scanning in a direction orthogonal to the transducer. That is, by simultaneously performing the electronic scanning and the mechanical scanning, a plurality of scanning planes (scanning plane arrays) are sequentially formed, and a three-dimensional data acquisition space is formed as a whole. When scanning the array transducer in the mechanical scanning direction, electronic scanning of the ultrasonic beam is performed in both the forward scan and the backward scan.

[0003] By the way, mechanical scanning is performed continuously,
Electronic scanning is repeatedly performed at a predetermined cycle. For this reason,
Each scan plane is not necessarily completely orthogonal to the machine scan direction,
It will slightly flow in the machine scanning direction. That is, there is a phenomenon that the scanning surface is distorted.

Conventionally, electronic scanning is always performed from one end to the other end of the array transducer regardless of the forward scan and the backward scan. That is, the direction of electronic scanning is unchanged. This is presumed to be to simplify the control of electronic scanning. However, there is a problem in image observation due to the fact that the direction of the distortion of the scanning surface in the forward scan is opposite to the direction of the distortion of the scanning surface in the backward scan. That is, when displaying the tomographic images corresponding to the respective scanning planes in real time, the inclination directions of the respective tomographic planes are reversed between the forward scan and the backward scan, so that there is a problem that a blurred image is difficult to see.

[0005]

In this regard, if the electronic scanning is executed in one direction in the forward scan and the ultrasonic beam is executed in the other direction in the backward scan, the directions of the distortions of the tomographic planes can be matched. Can be done. Therefore, there has been a demand for realizing such electronic scanning control with a simple circuit.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and an object of the present invention is to use a simple circuit configuration to detect each direction of a scan plane distortion caused by a forward scan and a scan plane distortion caused by a backward scan. It is to unify unnaturalness in image observation by unifying.

It is another object of the present invention to synchronize the mechanical scanning and the electronic scanning so that the positions of the respective scanning planes coincide in the forward scan and the backward scan.

[0008]

(1) In order to achieve the above-mentioned object, the present invention provides an array vibrator including N vibrating elements, and an array vibrator in a direction intersecting the arrangement direction of the N vibrating elements. A mechanical scanning mechanism for mechanically reciprocatingly scanning the array vibrator, and M mechanical devices connected in parallel to the N vibrating elements and used for forming an ultrasonic beam from among the N vibrating elements. M selection switches for selectively connecting the vibrating elements, and M selection switches selected by the M selection switches
M signal processors connected to the plurality of vibrating elements;
A switching controller for sequentially supplying number sequence data representing M selection element numbers to electronically scan the ultrasonic beam with respect to the number of selection switches, the switching controller comprising: A storage unit storing a plurality of number sequence data corresponding to each electronic scanning position of the beam; and when the forward scanning of the array transducer is performed, the storage unit stores the plurality of numbers in the M selection switches. A read control unit for sequentially outputting column data in ascending order, and when the backward scanning of the array vibrator is performed, for sequentially outputting the plurality of number sequence data in descending order from the storage unit to the M selection switches; , Is characterized by having.

According to the above arrangement, the electronic scanning direction of the ultrasonic beam is reversed between the forward scan and the backward scan, so that the inclination directions of the scanning surfaces can be made uniform. In addition, since the switching of the electronic scanning direction only needs to switch the reading direction of the series of number sequence data stored in the storage unit, the switching of the electronic scanning direction as described above can be realized with a simple circuit. If the number sequence data output from the storage unit is simultaneously supplied to the M selection switches, there is an advantage that element selection can be performed at high speed by each selection switch.

In the above configuration, the N vibrating elements are arranged, for example, in a straight line or an arc. The M vibrating elements selected from the N vibrating elements form a transmitting / receiving aperture that is moved and scanned on the N vibrating elements, where N and M are integers, and M is N Less than.
Each of the above signal processors is at least one of a transmitter and a receiver, but may be a transceiver. In this case, the M selection switches function both at the time of transmission and at the time of reception, and have an advantage in cost performance.

Further, in the above configuration, the storage unit stores the RO
It may be M, or may be composed of a RAM. According to the latter configuration, by software control,
The contents of a series of number sequence data can be easily rewritten, for example, when the size of the transmitting / receiving aperture is selected,
Accordingly, a series of number sequence data may be written in the RAM.

Preferably, the read control unit is a counter for sequentially generating a series of addresses in the storage unit. When the forward scan is performed, the read control unit counts up the counter so that the backward scan is performed. In the case where a counter operation is performed, a count operation control unit that counts down the counter is provided.

That is, a counter capable of counting up and counting down is used, and the address of a series of number sequence data can be specified in descending order and ascending order by utilizing the basic operation as it is. The electronic scanning direction can be controlled. If necessary, the count reset control may be performed at the end of the count and the count preset control may be performed before the count is started.

Preferably, the apparatus further includes a synchronizing signal generating section for generating a synchronizing signal at the time of conversion from the forward scan to the backward scan and at the time of conversion from the backward scan to the forward scan. Starts the count-up operation or the count-down operation.

Preferably, the array vibrator and the mechanical scanning mechanism constitute a three-dimensional probe, and the synchronization signal generator is provided in the three-dimensional probe. According to this configuration, the synchronization signal can be generated by actually detecting the movement of the array transducer in the three-dimensional probe, so that it is reliable and simple. In particular, since the synchronization signal can always be generated at an accurate timing, the position of the scanning surface can be matched between the forward scan and the backward scan.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a preferred embodiment of an ultrasonic diagnostic apparatus according to the present invention, and FIG. 1 is a block diagram showing the overall configuration.

The three-dimensional probe 10 is an ultrasonic probe for acquiring three-dimensional data. The three-dimensional probe 10 includes an array transducer 10A (see FIG. 2), a scanning mechanism (not shown) for mechanically scanning the array transducer 10A, an encoder for detecting a scanning angle, and generating a synchronization signal at each scanning end. And a synchronization signal generator (not shown). An ultrasonic beam is formed by the array vibrator, and while the ultrasonic beam is being electronically scanned, the array vibrator 1
By mechanically scanning OA itself, a three-dimensional data capturing area V as shown in FIG. 2 is formed. The three-dimensional data capturing area V is configured by a plurality of scanning planes.

The above-mentioned synchronizing signal generator comprises the array vibrator 1
0A is generated at the timing of switching from the forward scan to the backward scan (and from the backward scan to the forward scan). More precisely, a synchronization signal as a pulse signal is generated at the start timing of the forward scan and the backward scan. Of course, since the encoder is provided, it is possible to generate a synchronization signal on the device body side based on the output signal of the encoder, excluding the synchronization signal generator. However, if the predetermined position of the array transducer 10A is actually mechanically, electrically, and optically detected in the three-dimensional probe 10, a synchronization signal can be generated with more accurate timing. In FIG.
00, a synchronization signal is shown.
0 is input to the control unit 18.

The plurality of vibrating elements provided in the array vibrator 10A will be described later with reference to FIG.

A transmitting / receiving unit 12 is connected to the three-dimensional probe 10. A transmission signal is supplied from the transmission / reception unit 12 to the array transducer of the three-dimensional probe 10, and a reception signal from the array transducer is processed by the transmission / reception unit 12.

The mechanical scanning controller 14 and the electronic scanning controller 1
Reference numeral 6 denotes a circuit controlled by the control unit 18, and the mechanical scanning of the array transducer is controlled by the mechanical scanning control unit 14. Specifically, control for reciprocally scanning the array transducer in the machine scanning direction is executed. That is, the mechanical scanning direction includes the forward scan and the backward scan as described above.

The electronic scanning controller 16 has an ultrasonic beam forming function and a function of electronically scanning the beam.
The electronic scanning of the ultrasonic beam is sequentially performed from the predetermined end of the array transducer to the other end along with the mechanical scanning.
Various control signals 102 from the control unit 18 to the electronic scanning control unit
Are supplied, which include a start signal (STRT), a count direction designation signal (U / D), and a clock signal (CLK), which will be described later. A specific configuration example of the electronic scanning control unit 16 and the transmission / reception unit 12 will be described later with reference to FIG.
This will be described in detail with reference to FIG.

In this embodiment, the direction of the electronic scanning is set so that the distortion direction of the scanning surface coincides with the forward scan and the backward scan. This will be described later in detail with reference to FIG.

The three-dimensional image calculation unit 20 is a circuit that forms a three-dimensional image, a tomographic image, and the like based on each echo data acquired in the three-dimensional data capturing area V. Various calculation methods can be applied.

DSC (Digital Scan Converter) 2
Reference numeral 2 denotes a circuit for performing interpolation processing, coordinate conversion, and the like necessary for image formation. The frame memory included in the DSC 22 stores image data to be displayed. The image data is read out and displayed on the display unit 24.

In the above embodiment, as shown in FIG. 2, a pyramid-shaped three-dimensional data capturing area is formed. That is, the array transducer 10A has a so-called convex shape, and performs a convex scan of an ultrasonic beam to form a fan-shaped scanning surface, and swings and scans the fan-shaped scanning surface, thereby forming a pyramidal shape as shown in FIG. Is formed. However, the present invention can also be realized when electronic sector scanning or electronic linear scanning is applied.

FIG. 3 shows a scanning method according to this embodiment. Here, (A) shows a forward scan,
(B) shows the backward scan. Incidentally, the horizontal direction on the paper indicates the mechanical scanning direction (main scanning direction), and the vertical direction on the paper indicates the electronic scanning direction (sub-scanning direction).

In this embodiment, as shown in FIG. 3, for example, in the forward scan, the array transducer 10A
Is performed from one end to the other end, and in the backward scanning, the electronic scanning is performed in the opposite direction, that is, from the other end to one end. As a result, it is possible to make the direction of the distortion of the scanning surface in the forward scan coincide with the direction of the distortion of the scanning surface in the backward direction. By the way,
The scanning speeds in the forward scan and the backward scan coincide with each other, and the positions of the scanning surfaces can be matched.

By the way, in FIG.
Numbers # 1 to #N representing transmission / reception elements are assigned near 0A. According to this number, in the forward scan #
Electronic scanning is performed from # 1 to #N, and in the backward scanning, electronic scanning is performed from #N to # 1. However, at the time of actual transmission / reception, a group of a group of vibrating elements adjacent to each other is selected, a transmission / reception aperture for forming an ultrasonic beam is set by using them, and such a transmission / reception aperture is electronically scanned. Is done.

In FIG. 3, reference numeral 200 indicates the timing of generation of a synchronization signal generated at the start of forward scan.
Reference numeral 202 indicates the generation timing of the synchronization signal generated at the start of the backward scanning.

FIG. 4 shows a comparative example. In the comparative example, in order to simplify the electronic scanning control, the electronic scanning direction is the same in both the forward scan and the backward scan. That is, the electronic scanning from # 1 to #N is performed in both the forward scan and the backward scan. As a result, as shown in FIGS. 4A and 4B, the inclination directions of the scanning planes do not match between the forward scan and the backward scan, and as a result, particularly when switching from the forward scan to the backward scan and when returning from the backward scan. When the scan direction is changed back to the forward scan, the distortion direction of the scan surface is suddenly changed, giving an uncomfortable feeling to the image observer.

On the other hand, according to the scanning direction according to the present embodiment shown in FIG. 3, the distortion direction can be made coincident even at the time of such switching, so that there is an advantage that the sense of discomfort to the observer can be eliminated. .

In the present embodiment, tomographic images corresponding to sequentially formed scan planes are sequentially displayed on the display section 24, and are formed stepwise using each scan plane. A three-dimensional image is also displayed.

FIG. 5 is a specific block diagram showing the main configuration of the ultrasonic diagnostic apparatus shown in FIG. As shown in FIG. 2, the three-dimensional probe 10 includes an array vibrator 10A, and the array vibrator 10A has a plurality of vibrating elements. In the present embodiment, #
For example, 256 vibrating elements 1 to #N are provided. Incidentally, in FIG. 5, reference numeral 204 denotes a transmission / reception opening, and the transmission / reception opening 204 is configured by M vibration elements selected from N vibration elements.
That is, a transmitting beam and a receiving beam as an ultrasonic beam are formed using the M vibrating elements arranged adjacent to each other. Then, electronic scanning of the ultrasonic beam is performed by electronically scanning the transmission / reception opening 204 along the arrangement direction of the vibration elements.

The transmission / reception section 12 includes a multiplexer (MPX) group 30 and a transceiver group 3 in the configuration example shown in FIG.
2 and an adding circuit 36. MPX group 30
Is constituted by N multiplexers (MPXs), as will be described later with reference to FIG. 6. Each MPX is connected to all M vibration elements, and the MPX is one of them. The vibration element is selected, and the selected vibration element is connected to the transceiver 34 associated with the MPX.

The transceiver group 32 is composed of M transceivers 34, and each transceiver 34 is connected to one MPX associated therewith. Transceiver 34
Are the transmitter (Tx) and the receiver (R
x), and the output side of the receiver is connected to the adding circuit 36. Incidentally, a transmission signal supply circuit and the like connected to the transmitter are not shown in FIG.

The adder circuit 36 is a circuit for adding the received signals output from the M receivers. Specifically, each receiver gives a predetermined delay time to the received signal, Each received signal to which time has been added is added to an adder 3
6 has been added. Thereby, so-called phasing addition is realized. The received signal after the phasing addition is
The data is output to the three-dimensional image calculation unit 20 as shown in FIG.

In this embodiment, as shown in FIG. 5, the electronic scanning control section 16 has a switching controller 38. As described above, the switching controller 38 includes a clock signal (CLK), a count operation designation signal (U / D), and a start signal (STRT) from the control unit 18.
The switching controller 38 controls the operation of each MPX constituting the MPX group 30 according to these signals.

FIG. 6 shows a specific configuration example of the switching controller 38. MPX group 3
0 shows a specific configuration example.

As described above, the MPX group 30 includes
It is composed of M MPXs 40 up to #M.
Each MPX 40 is provided in parallel with the N vibration elements, and N vibration elements are connected to each MPX 40. Each MPX 40 is connected to a corresponding transceiver 34. By the way, FIG.
In order to explain the operation at the time of reception, each MPX4
Although the IN terminal and the OUT terminal are clearly shown at 0, the signal flow is reversed during transmission, and the MPX 40 functions bidirectionally. The C / S terminal in each MPX 40 is a terminal for receiving a chip select signal. The RGT terminal is a terminal for inputting number sequence data output from a ROM 42 described later. Here, the number sequence data is data composed of N numbers representing the numbers of the vibrating elements constituting the transmitting / receiving aperture 204 shown in FIG. When such number string data is given to each MPX 40,
Each MPX 40 specifies an element number corresponding to itself and performs an operation of selecting a channel of the element number, that is, a vibration element.

Therefore, certain number string data is stored in each MPX
When set to 40, M vibration elements specified by the number sequence data, that is, M channels
Will be connected to the transceivers 34.

Incidentally, in FIG. 6, each MPX 40 is formed separately,
It is also possible to construct the device with physical integrity in an electrically separated form.

In FIG. 6, the switching controller 38 shown in FIG. 5 includes a counter 44,
And a ROM 42. The ROM 42 stores a series of a plurality of number sequence data as shown in FIG.
One number sequence data corresponds to one address of the ROM. Each number string data is from the first channel to the M-th channel.
The first number sequence data is, for example, element number # 1.
To element number #M. Similarly, the second number sequence data includes element numbers # 2 to # 2.
It is composed of element numbers up to element number # M + 1. The same applies to other number string data.

In this embodiment, as shown in FIG. 8, N-M + 1 number sequence data is stored in the ROM 42. When the counter 44 performs a count-up operation, each number sequence data is stored in the ROM 42 in the address order. When the data is sequentially read and the counter 44 is operated to count down, each number sequence data is read from the ROM 42 in the reverse order. Incidentally, although the output of the counter 44 is given M bits, the output is not limited as long as the address of the ROM 42 can be specified.

The operation of the counter 44 will be further described. The counter 44 counts a clock signal. When the count operation designating signal designates an up-counting operation, the counter 44 starts counting the clock signal after inputting the start signal. Is counted, and the count value is counted up. Here, the count value is output from the counter 44 to an address terminal of the ROM 42. Conversely, when the count operation designation signal designates a down count, the clock signal is counted down by the counter 44 after the start signal is input, and the count value is output to the address terminal of the ROM 42.

In this embodiment, in the forward scan shown in FIG. 3, the operation of the counter 44 is counted up, while in the backward scan, the operation of the counter 44 is counted down. Have been. As a result, as shown in FIG. 3, the forward scanning and the backward scanning can reverse the electronic scanning direction of the ultrasonic beam, that is, the moving direction of the transmission / reception opening 204 shown in FIG.
Furthermore, in both the forward scan and the backward scan, it is possible to make the distortion directions of the scanning plane coincide.

In this embodiment, the control unit 18
Since a start signal synchronized with the synchronization signal 100 is generated and used as the operation start signal of the counter 44, the operation start timing of the count-up and count-down can always be set correctly.
In other words, the mechanical scanning and the electronic scanning can be completely synchronized.

FIG. 7 shows a specific configuration example of the MPX 40 shown in FIG. The selector 46 is connected to the register 4
8 is a circuit for selecting any one of the channels # 1 to #N according to the information set in the channel 8. The register 48 stores the number sequence data output from the ROM 42 with a P-bit data amount. Specifically, the output of the number sequence data from the ROM 42 is performed in synchronization with a clock signal, and the clock signal is input to the set terminal of the register 48 as a chip select signal. The number sequence data is set in the register 48 at the timing when the signal is input. Then, in the number sequence data set in the register 48, the number corresponding to the MPX 40 is identified,
The channel corresponding to the number is selected by the selector 46. As described above, in the present embodiment, the register 48 stores all of the number sequence data.
It is also possible to selectively set only the number data corresponding to X40 in the register 48. In any case, R
Based on the number sequence data output from the OM 42, the M MPXs 40 are each configured to select a channel for which the MPX 40 is responsible.

According to the embodiment described above, the ROM 4
A plurality of number sequence data corresponding to a series of electronic scanning positions is stored in the memory 2 and the number sequence data is read out in ascending or descending order by operating the counter 44 to perform an up-count operation or a down-count operation. Therefore, there is an advantage that the electronic scanning of the transmission / reception aperture corresponding to the forward scan and the backward scan can be realized with an extremely simple configuration. Further, as described above, since the operation of the counter 44 is completely synchronized with the output pulse of the synchronization signal generator provided in the three-dimensional probe 10, the operation of the counter 44 is completely matched with the mechanical scanning timing. It is possible to avoid the problem caused by the electronic scanning and the mechanical scanning being out of synchronization.

In the above embodiment, as shown in FIG. 6, the switching controller 38 is provided with the ROM 42. However, the switching controller 38 is constituted by a RAM so that a plurality of number sequence data can be rewritten by software. Is also good. According to such a configuration, it is possible to variably set the size of the transmitting / receiving aperture. The maximum variable range will depend on M. In other words, the configuration is such that a circuit to be actually operated can be selected from among the M circuits.

Although FIGS. 6 and 7 show the flow of signals during reception, the flow of such signals is reversed during transmission. However, in such transmission, the switching controller 38 may be operated in the same manner as in reception, and in that sense, there is an advantage that cost performance can be improved.

[0053]

As described above, according to the present invention,
With a simple circuit configuration, it is possible to unify the distortion of the scanning surface caused by the forward scanning and the distortion of the scanning surface caused by the backward scanning so as to unify the discomfort in image observation. Further, according to the present invention, it is possible to synchronize the mechanical scanning and the electronic scanning, and to match the positions of the respective scanning surfaces in the forward scan and the backward scan.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the overall configuration of an ultrasonic diagnostic apparatus according to the present invention.

FIG. 2 is a diagram illustrating an example of a three-dimensional data capturing area.

FIG. 3 is a conceptual diagram illustrating a scanning method according to the embodiment.

FIG. 4 is a conceptual diagram showing a conventional scanning method.

FIG. 5 is a diagram showing a main configuration of the ultrasonic diagnostic apparatus.

FIG. 6 is a diagram illustrating a specific configuration example of a switching controller and an MPX group.

FIG. 7 is a diagram showing a specific configuration example of MPX.

FIG. 8 is a diagram showing a number sequence data table.

[Explanation of symbols]

10 3D probe, 10A array transducer, 12
Transmitting / receiving unit, 14 mechanical scanning control unit, 16 electronic scanning control unit, 18 control unit, 20 three-dimensional image calculation unit, 22D
SC (digital scan converter), 24 display units,
30 multiplexer group, 32 transceiver group, 36 addition circuit, 38 switching controller, 40 multiplexer, 44 counter, 46 selector.

 ────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Yuko Yamashita 6-22-1, Mury, Mitaka-shi, Tokyo Aloka Inc. F-term (reference) 4C301 AA02 BB01 BB02 BB13 BB19 BB22 BB28 BB34 BB35 EE07 GA20 GB03 GB06 GD02 HH11 5D019 AA21 BB18 FF04

Claims (4)

[Claims] An array vibrator including N vibrating elements; a mechanical scanning mechanism configured to mechanically reciprocally scan the array vibrator in a direction intersecting an arrangement direction of the N vibrating elements; M selection switches that are connected in parallel to the plurality of vibration elements and selectively connect M vibration elements to be used for forming an ultrasonic beam from the N vibration elements. M signal processors connected to the M vibrating elements selected by the selecting switches, and M selecting elements for electronically scanning the ultrasonic beam with respect to the M selecting switches. A switching controller for sequentially supplying number sequence data representing a number, wherein the switching controller stores a plurality of number sequence data corresponding to each electronic scanning position of the ultrasonic beam, and the array vibration Child's outbound When the inspection is performed, the plurality of number string data is sequentially output from the storage unit to the M selection switches in ascending order, and when the return scanning of the array transducer is performed, A reading control unit for sequentially outputting the plurality of number sequence data to the M selection switches in descending order; 2. The apparatus according to claim 1, wherein the read control unit is a counter that sequentially generates a series of addresses in the storage unit, and counts up the counter when the forward scan is performed. An ultrasonic diagnostic apparatus, further comprising: a count operation control unit that counts down the counter when the backward scan is performed. 3. The apparatus according to claim 2, further comprising: a synchronization signal generation unit configured to generate a synchronization signal when the forward scan is switched to the backward scan and when the backward scan is switched to the forward scan. Starts the count-up operation or the count-down operation in response to the input of the synchronization signal. 4. The apparatus according to claim 3, wherein the array transducer and the mechanical scanning mechanism constitute a three-dimensional probe, and the synchronization signal generator is provided in the three-dimensional probe. Ultrasonic diagnostic equipment.