JPH02232040A - Ultrasonic diagnostic device - Google Patents

Abstract

PURPOSE:To enable dynamic focusing only in the phasing circuit of one sequence, to miniaturize the phasing circuit and to lower a cost by using a variable delay circuit and providing the variable delay circuit for each signal group formed by adding plural signals as one group out of received signals from the respective oscillators of a probe. CONSTITUTION:The phasing circuit is composed of cross point switches 14a, 14b,..., 14m, LC delay lines 16a, 16b,..., 16m, variable delay circuits 17a, 17b,..., 17m, cross point switch 19 and LC delay line 21. The plural cross point switches 14a, 14b,..., 14m are provided in an input side and for these cross point switches, input signal lines 13, 13,... are connected for each input terminal out of input terminals #1, #2, #3,..., Hn to which the received signal is inputted from each oscillator of the probe. The LC delay lines 16a, 16b,..., 16m are provided in the input side and for these LC delay lines, respective taps are connected to respective output signal lines 15, 15,... The variable delay circuits 17a, 17b,..., 17m are provided to be respectively connected through termination resistors to an output side and to give a delay time to the received signal. The cross point switch 19 is provided in the output side and for this cross point switch, an input signal line 18 is connected to the output terminal of this variable delay circuit. Then, the LC delay line 21 is provided in the output side and for this LC delay line, the respective taps are connected to an output signal line 20.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention is an ultrasonic wave that enables dynamic focusing by using a variable delay circuit that can continuously change the delay time according to an electric signal as a delay circuit in a phasing circuit. Related to diagnostic equipment. [Prior art] Ultrasonic diagnostic equipment transmits and receives ultrasonic waves to and from a subject using a probe, and obtains information inside the subject based on reflected wave signals from within the body. ．Here, in order to obtain high-resolution images at any location at different depths inside the subject, when receiving reflected waves from within the body, the focus of the received waves is moved over time. At this time, the received waves are focused using a probe with a plurality of transducer elements arranged in a narrow strip shape, or a probe with a plurality of transducer elements arranged in a concentric circle. This is done by appropriately delaying and adding the received signals from each of the above-mentioned transducer elements of a probe consisting of a ring-shaped transducer element using a delay line.This circuit is generally called a phasing circuit. Since the focal point position for delivery is determined by the delay time of each delay line mentioned above, dynamic focus adjusts the delay time to be given to multiple received signals according to the generation depth of reflected waves from within the body. This is achieved by dynamically changing the delay time.The delay time described above is changed by providing taps at appropriate intervals on the delay line and selecting and switching these taps using an electronic switch.In this case, the above-mentioned electronic switch Noise may be generated when switching, and may be mixed into the received signal via the delay line, resulting in erroneous signals appearing in the diagnostic information.In order to improve this phenomenon, we have A switch that generates little noise may be used as the electronic switch, but such electronic switches are expensive, and if a large number are provided for each tap of the delay line, the price will increase and it will be uneconomical. To deal with the above problems, two systems of phasing circuits each having a delay line with a tap changeover switch and different focal lengths are used alternately, and one phasing circuit is A device that switches the taps of the other phasing circuit while it is being used is disclosed in Japanese Patent Application Laid-Open No. 56-112234.
This is proposed in the publication. As shown in FIG. 11, the conventional ultrasonic diagnostic apparatus described in this publication includes an array-type probe 2 in which a plurality of transducer elements 111 xat..., 1n are arranged and transmit and receive ultrasonic waves. and a two-system phasing circuit 3 that gives a predetermined delay time to the received signals from each of the transducer elements 11 to 1n of the probe 2, aligns the phases, adds them, and outputs the results.
, 3', an amplifier 4.4' that amplifies the signal of the terminal resistor of each delay line in these phasing circuits 3, 3', and output signals from the two phasing circuits 3, 3'. Electronic switch for switching alternately? 5, a detector 6 for detecting and compressing the signals phased by the respective phasing circuits 3 and 3', and a display device 7 for displaying the output signal from the detector 6 as an image. It was done. Here, the above two systems of phasing circuits 3,
3' denotes each transducer element 1 - 1 of the probe 2, respectively.
A constant current source output type amplifier that inputs and amplifies the received signal from n 819811...8 n; 81 s 8
2...8n', delay lines 9, 9', and tap changeover switches 10, 10!, each consisting of an electronic switch for selecting and switching the taps provided at appropriate intervals on these delay lines 9, 9'. ,...Ion: Loz i
It consists of o2 ``”* Ion'. In FIG. 11, reference numeral 11 is a controller for switching and controlling the electronic switch 5 and the tap changeover switches 1oE-10n, 10,'-Ion'. In the ultrasonic diagnostic apparatus configured in this way, each of the above-mentioned tap changeover switches 10, to ion and 10
■' to Ion' are switched while the output ends (4, 4') of the phased matching circuit 3 or 3' to which they belong are separated from the next stage (detector 6) by switching the electronic switch 5. Therefore, the tap changeover switches 101 to I
The noise generated by turning on or the operation of 101' to 10n' does not mix into the signals of the next stage and subsequent stages. Therefore,
A large number of tap changeover switches 101 to Io are required.
n and 101' to 10n' can be replaced by inexpensive switches that may generate noise. At this time, the electronic switch 5 that alternately switches the output signals from each phasing circuit 3, 3' switches the part where the signal is constantly flowing, so an expensive switch that generates little noise must be used. Since the number of units is small, the price does not particularly increase, and overall cost increases can be suppressed. As a result, each tap changeover switch 101 to Ion during dynamic focus
Or, it was made so that it would not be affected by the noise generated by switching between 101' and 10n'. (Problem to be solved by the invention) However, in such conventional ultrasound diagnostic equipment,
As shown in FIG. 11, since two systems of phasing circuits 3 and 3' are provided, two systems of expensive delay lines 9 and 9' are required, which increases the circuit scale and costs. It was something. Furthermore, the above two systems of phasing circuits 3, 3'
If there is a sensitivity difference in the signals from the output side electronic switch 5
Due to this switching, a difference in brightness and darkness will occur in the image displayed on the display device 7, so it is necessary to use parts with little variation in characteristics, which requires a lot of adjustment time. This also caused an increase in costs. In addition, the above two systems of phasing circuits 3, 3
Even if the difference in sensitivity of was to occur.

Therefore, an object of the present invention is to provide an ultrasonic diagnostic apparatus that can solve these problems. [Means for Solving the Problems] In order to achieve the above object, an ultrasonic diagnostic apparatus according to the present invention includes a probe in which a plurality of transducer elements are arranged and transmits and receives ultrasonic waves, and a probe for transmitting and receiving ultrasonic waves. A phasing circuit that has a delay circuit that gives a predetermined delay time to the received signal from each transducer element and adds and outputs the received signals whose phases are aligned in these delay circuits, and this phasing circuit. An ultrasonic diagnostic apparatus comprising a detector that detects a phased signal and a display device that displays the output signal from the detector as an image. The above-mentioned phasing circuit uses a variable delay circuit that continuously changes the delay time using an electric signal as an internal delay circuit, and also uses a variable delay circuit that continuously changes the delay time using an electric signal. The variable delay circuit described above is provided for each signal group formed by adding a plurality of signals as a group after giving a fixed delay time. In addition, the above-mentioned phasing circuit adds a delay circuit that gives a minute delay that changes over time to each received signal from each transducer element of the probe, and also adds a delay circuit that gives a minute delay that changes over time to each received signal from each transducer element of the probe. It may also be possible to control each signal channel independently. [Function] The ultrasonic diagnostic device configured as described above uses a variable delay circuit in which the delay time is continuously changed by an electric signal as a delay circuit in the phasing circuit.
Dynamic focusing can be achieved with just one phasing circuit. In addition, the variable delay circuit described above is provided for each signal group formed by adding together multiple signals among the received signals from each transducer element of the probe, so that the variable delay circuit can be installed within the phased parallel path. The number of variable delay circuits can be reduced, and the above-mentioned phasing circuit can be made smaller and cheaper. [Example] Hereinafter, an example of the present invention will be described in detail based on the accompanying drawings.

FIG. 1 is a block diagram showing an embodiment of a phasing circuit in an ultrasonic diagnostic apparatus according to the present invention. This ultrasonic diagnostic device transmits and receives ultrasonic waves to and from a subject and obtains diagnostic information inside the subject based on echoes reflected from within the body. The probe has a probe arrayed in the array that transmits and receives ultrasonic waves, and a delay circuit that gives a predetermined delay time to the received signal from each transducer element of this probe, and the phases are aligned by these delay circuits. Comprised of a phasing circuit that adds and outputs received signals, a detector that detects the signal phased by this phasing circuit, and a display device that displays the output signal from the detector as an image. ．． The above-mentioned phasing circuit (see reference numeral 12 in FIG. 1) is
As shown in FIG. 1, input terminals #1, 62, #3, . . . receive signals from each transducer element of a probe not shown.
..., input signal line 1 for each plurality of input terminals among #n
3, 13, . . . are connected to a plurality of input side cross point switches 14a, 14b . ..., 14m and
LC delay lines 16a, 16b, -, 16 on the input side whose taps are connected to the output signal lines 15, 15, . . . of each of these cross point switches 14a to 14m.
m, variable delay circuits 17a, 17b, . . . 17m connected to the output side of each of these LC delay lines 16a to 16m via a terminal resistor and giving a delay time to the received signal, and these variable delay circuits. The cross point switch 19 on the output side has the input signal lines 18, 18, . . . connected to the output terminals 17a to 17m, and the output signal lines 20, 20, . It consists of a connected output side LC delay line 21. In FIG. 1, reference numeral 22 indicates each of the variable delay circuits 17a described above.
17m, the reference numeral 23 indicates the cross point switches 14a to 14m on the input side.
and a control unit that controls the operation of the cross-point switch 19 and the control circuit 22 on the output side, and reference numeral 24 indicates an output terminal of the phasing circuit 12. Here, in the present invention, as each of the variable delay circuits 17a to 17m in the phasing circuit 12, a second-order or higher-order active all-bus filter having the circuit configuration shown in FIG. 2 is used. The variable delay circuits 17a to 17m, which are composed of second-order or higher-order active all-bus filters, differ from those using conventional delay lines in that their delay times vary continuously depending on the electrical signal applied to their control terminals. , the thought process that led to its composition is shown in Figures 3 to 9.
This will be explained with reference to the figure. First, as shown in Figure 3, instead of the so-called LC delay line, which consists only of passive elements such as inductors and capacitors, which were used in conventional phasing circuits, passive elements such as inductor L and capacitor C and an amplifier are used. This section describes a delay circuit consisting of an equalizer, also called an all-bus filter. This delay circuit has variable amplitude characteristics and delay characteristics. The transistor Q0 functions as a phase divider, and the amplitude of the signal applied to the emitter follower Q2 is K times the input amplitude.

Next, the equivalent circuit of the all-bus filter shown in Figure 3 is shown in Figure 4. In the circuit shown in Fig. 4, if the Laplace transform operator is S, then the transfer function T(S) representing the ratio of the output signal to the input signal is obtained by superposition as follows. If we set K=1 in this equation (1), we get the equation of the second-order all-pass transfer function. That is,
In the above equation (1), as K increases or decreases from 1, the amplitude characteristics rise or fall at the center frequency. To illustrate this situation, as shown in the graph shown in Figure 5, the gain approaches 1 as the signal frequency approaches zero or becomes infinite. The maximum delay time T dmax occurs at the LC resonance frequency and is expressed by the following equation. Tdmx=2RC/K+2RC
=- (3) If K=1 in this equation (3),
Tdmax is as follows. Tdsax = 4RC
- (4) Next, if the all-bus filter shown in Fig. 3 is realized using an operational amplifier, the circuit configuration shown in Fig. 6 will be obtained. That is, the inductor L, the capacitor C, the operational amplifier 25, and the operational amplifier 25
a variable resistor R connected to one input of the operational amplifier 25, a resistor R' connected to the other input, and a variable resistor KR' fed back from the output side of the operational amplifier 25 to the other input.
It consists of. Here, the value of the resistance R' is arbitrary, and the above equations (3) and (4) can be applied. The following can be said from these equations. ■When K=1, the maximum delay time Td■az is equal to 4RC. Therefore, by changing the resistance value of variable resistor R. The size of the delay time can be controlled. ■The maximum delay time Tdmax is not affected much even if K deviates from 1. ■The amount of amplitude equalization at the LC resonance frequency is independent of the delay setting and is a function only of K. Additionally, the delay time can be changed without affecting the amount of equalization. Here, an example of the delay characteristic when the delay time is changed by changing the resistance value of the variable resistor R shown in FIG. 6 is shown in FIG. 7. That is, it can be seen that by changing the resistance value of the variable resistor R, the larger the delay time Td becomes, the narrower the frequency width at which the delay time Td is constant. As described above, by setting K=1 and making the resistance R variable in the second-order all-pass filter expressed by the above equation (2), the maximum delay time Tdmax can be set to an appropriate value to create a variable delay. It can be seen that the circuit can be realized. The above information is based on the book "Electronic Filter Design Handbook" by Arthur B. Williams, McGraw-Hill Publishing, 1981.
．． Williams ``Electro-nic F
Ilter Design Handbook” Mc
It is also described in Graw-}till 1981). The delay time can be changed continuously with the circuit shown in Figure 6, but when this circuit is applied as a delay circuit to the phasing circuit of an ultrasound diagnostic device, the amplitude characteristics (see Figure 5) and the delay characteristics (see Figure 7) ) can be set arbitrarily, which is convenient. In order to achieve dynamic focus in an ultrasonic diagnostic apparatus, it is required to be able to control the delay time at high speed and without introducing noise into the received signal. In order to meet these requirements, a circuit equivalent to the variable resistor R of the delay circuit shown in Fig. 6 whose resistance value can be controlled by an electrical signal is shown in Fig. 8. The circuit of FIG. 8 is an amplifier 26 whose voltage gain G can be controlled by an electrical signal Ev.
is fed back with a constant resistor R, and the resistance value of the circuit is made variable. The amplifier 26 described above can be realized by, for example, a Gilbird cell having the circuit configuration shown in FIG. It's small and practical. Here, the impedance seen from the input terminal 27 of the amplifier 26 is determined. At this time, the input impedance of the amplifier 26 is infinite, the output impedance is zero, the input voltage at the input terminal 27 is Ein, the current is
i, and the output voltage at the output terminal 28 is Eout,
The following formula holds.

Ein-Ri-Eout=O
・= (5) Eout = −G−Ein
- (6) This part (5)
By eliminating E out from the equation and equation (6), R Ein = − i
...(7)1+G. Then, when the equation of this input voltage E1n is partially differentiated with respect to the current i, the impedance Zin seen from the input terminal 27 is
is as follows. ai 1+G If the gain G is changed in this equation (8), the input terminal 27
The impedance Zin seen from will change.
That is, the resistance between the input terminal 27 of the circuit shown in FIG. 8 and the ground can be controlled by the electric signal Ev. For example, if the gain G is changed from 0 to 4, the impedance Zin at the input terminal 27 will be changed from R to 0.2R. As a result, Figure 8 becomes a variable resistance circuit. Therefore, by applying the variable resistance circuit in which the resistance between the input terminal 27 and the ground is variable according to the electric signal Ev shown in FIG. 8 to the variable resistor R shown in FIG. 6, the present invention shown in FIG. Such variable delay circuits 17a to 17m are configured.
That is, inductor L, capacitor C, and operational amplifier 2
5 is used to configure a second-order or higher active all-bus filter that provides a delay time at the LC resonance frequency, and the gain G can be controlled by the electric signal Ev at the resistor part connected to the input terminal of the operational amplifier 25. A constant resistance R is applied to the amplifier 26.
A variable resistance circuit 29 is provided which makes the resistance value variable using a feedback circuit, and this variable resistance circuit 29 makes the resistance in the active all-pass filter variable. In FIG. 2, the symbol R' is a constant resistor connected to the other input section of the operational amplifier 25, and the symbol KR' is a constant resistor that performs feedback from the output side of the operational amplifier 25 to the other input section. It is a variable resistor. Then, the gain G of the amplifier 26 of the variable resistance circuit 29 is set at the control terminal 30.
The delay time can be changed continuously by changing the electric signal (control voltage Ev) applied to the control voltage Ev. Further, in the present invention, each of the variable delay circuits 17a to 17a-
17m is the cross point switch 14a on the input side.
By connecting to the output sides of the LC delay lines 16a to 16m connected to the output signal lines 15, 15, . For example, one signal is provided for each signal group formed by adding four received signals as a group. Next, the operation of the phasing circuit 12 configured as described above will be explained with reference to FIG. First, a received signal from each transducer element of a probe (not shown) is amplified by an amplifier (not shown), and then applied as a constant current signal source to each input terminal #l to #n. These input terminals #1 to #n include, for example, four input terminals #1 to #4. Each cross point switch 14a, 14b, . . . for each #5 to #8, .
14m, these crosspoint switches 14a to 14m and the LC delay lines 16a to 16m connected to the output signal lines of the crosspoint switches 14a to 14m, for example, add up the signal group for each of the four received signals as one group. It is formed. Then, each signal group output from the termination resistor whose impedance has been matched with the characteristic impedance of each of the LC delay lines 16a to 16m is input to variable delay circuits 17a, 17b, . . . , 17m, respectively. These variable delay circuits 17a to 17m adjust the speed at which the ultrasound propagates within the body of the subject by the control signal S, (the electrical signal input to the control terminal 30 in FIG. 2) from the control circuit 22. Correspondingly, in order to realize dynamic focusing that moves the convergence point of the ultrasound beam to a deep place,
An appropriate delay time is given to the received signal. The output signals of the variable delay circuits 17a to 17m given delay times in this way serve as constant current signal sources, and are connected to the cross point switch 19 on the output side, its input signal line 18,
Input via 18,... The signal input to this cross-point switch 19 is sent to the LC delay line 21 on the output side, and the output signal lIA20, 20, . . .
The number of taps provided at appropriate intervals is the same as the number of taps provided at appropriate intervals, and the signals given appropriate delay times by each of the variable delay circuits 17a to 17m are further routed through the taps selected by the crosspoint switch 19. It is input to the LC delay line 21, a delay corresponding to the delay time corresponding to the tap position is given, and nine signals are added to each.
At this time, each cross point switch 14a on the input side
14m and the cross point switch 19 on the output side are controlled by control signals S8, S from the control unit 23 so as to provide a delay time corresponding to the deflection angle of the ultrasound beam. As described above, the signal that has been delayed, added and phased by the phasing circuit 12 is output from the output terminal 24, and after being detected with a detection amount not shown, is input to the display device. Displayed as an image. With such a configuration and operation, each of the variable delay circuits 17a to 17m in the phasing circuit 12 operates as its control terminal. 30 (see Figure 2), the delay time can be changed continuously by simply inputting an electrical signal to the phasing circuit 30 (see Figure 2). Focus can be achieved. Furthermore, since each of the variable delay circuits 17a to 17m described above does not need to be provided for each channel of received signals from a large number of transducer elements of the probe, the number of variable delay circuits to be installed can be reduced. ．． In addition,
When the delay time to be changed is relatively large, each of the variable delay circuits 17a to 17m is constructed by connecting multiple stages of active all-pass filters of second or higher order in the circuit configuration shown in FIG. It may also be configured by connecting a conversion circuit. FIG. 10 is a block diagram showing a phasing circuit in a second embodiment of the present invention. The phasing circuit 12' of this embodiment includes delay circuits 31-1, 31-2, 31. ,...,31
In addition to adding n, the delay time of the delay circuits 31L to 31n is set to the channel of the received signal. Each channel is controlled independently. In other words, the input terminals #1, $2, # input the received signals from each transducer element of the probe.
3,...#n and each cross point switch 1 on the input side
Between the input signal lines 13, 13, . . . 4a to 14m, delay circuits 31■, 31■ 313, . The delay time of the delay circuits 311 to 31n is controlled independently for each channel of each received signal by a control signal S4 from the control circuit 22. Here, each of the delay circuits 311 to 31n needs only to be able to control minute delay times, so for example, a first-order active all-bus filter is used, and the output signal thereof is made to serve as a constant current signal source. In addition, each of the delay circuits 31, to 31n has input side LC delay lines 168 to 16.
In order to further increase the resolution of the delay time determined by the number of taps in m, the delay time is initially set. In the phasing circuit 12' having such a configuration, D? Variable delay circuits 17a to 17 to realize dynamic focus
When the delay time m is continuously changed, the received signal from each transducer element of the probe is delayed by each delay circuit 31■ to 31n, and then the signal is added for each channel. The delay time will change continuously. Therefore, in order to realize dynamic focus, for example, in a configuration in which the received signals of four channels are added, the change in delay time that should be given to each channel is different, so these values are added to each delay circuit 311 to 31n. It is necessary to control each channel individually. Therefore,
In the embodiment shown in FIG. 10, each of the delay circuits 31
The delay times 1 to 31n are determined by the control signal S.1 to 31n from the control circuit 22. is controlled independently for each channel of each received signal. This delay time and the control timing of the delay time are determined by the LC delay lines 16a to 16m on the input side and the LC delay lines 16m on the output side.
Since it differs depending on the tap position of the delay line 21, the timing of the control signal S4 is determined as follows. That is,
The timing at which a signal appears at the input section of each variable delay circuit 17a to 17m differs depending on the tap position of the LC delay @16a to 16m on the input side to which the received signal of each channel is applied. Therefore, in order for the received signals inputted at the same timing to the input terminals #1 to #n of the channels of each received signal to be phased and summed, each channel must be controlled by each cross point switch 14a to 14m on the input side. Each of the delay circuits 311 to 31n may be controlled with a time delay corresponding to the delay time of the tap position of each selected LC delay line 16a to 16m. In the case of this embodiment, the resolution of the delay time determined by the number of taps of the input side LC delay lines 16a to 16m is further subdivided by providing a minute delay with each of the delay circuits 31, to 31n. hand,
The resolution of the delay time can be improved. Note that the variable delay circuits 17a to 17a shown in FIGS. 1 and 10
17m is not limited to the second-order or higher-order active all-pass filter having the circuit configuration shown in FIG. 2, but may be of any other circuit configuration as long as the delay time can be continuously changed by an electrical signal. [Effects of the Invention] Since the present invention is configured as described above, variable delay circuits 17a to 1 are used as delay circuits in the phasing circuit 12 or 12'.
By using 7m, it is possible to move the convergence point of the ultrasonic beam to a desired position by continuously changing the delay time just by applying an electric signal to its control terminal. Therefore, unlike the delay lines in conventional phasing circuits, noise is not generated, so there is no need to provide two systems of phasing circuits and use them alternately, and one system of phasing circuits (12 or 12 ′
) alone can achieve dynamic focus. From this, the circuit scale can be reduced,
It is possible to downsize the device and reduce costs. In addition, instead of switching and displaying signals from two phasing circuits as in the past, the signal from one phasing circuit is simply displayed on the display device.
Images with uniform quality can be obtained without any differences in brightness and darkness, making diagnosis easier. Furthermore, the variable delay circuits 17a to 17m are provided for each signal group formed by adding together a plurality of signals among the received signals from each transducer element of the probe, and each of the received signals is Since they do not need to be provided for each signal channel, the number of variable delay circuits 17a to 17m in the phasing circuits 12, 12' can be reduced. Therefore, it is possible to downsize the entire device and reduce costs. Also,
A delay circuit 31 that provides a minute delay that changes over time for each received signal from each transducer element of the probe.
In the case of adding 1 to 31n, the resolution of the delay time can be easily improved.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of a phasing circuit in an ultrasonic diagnostic apparatus according to the present invention, FIG. 2 is a circuit diagram showing an example of a variable delay circuit in a phasing circuit according to the present invention, and FIGS. FIG. 9 is a circuit diagram and graph for explaining the thought process that led to the construction of the variable delay circuit described above, and FIG. A block diagram showing a phasing circuit in an embodiment, and FIG. 11 is a block diagram showing a conventional ultrasonic diagnostic apparatus. 12, 12'... phasing circuit, 14a to 14m...
Input side cross point switch, 16a~16m
... LC delay line on the input side, 17a to 17m... variable delay circuit, 19... cross point switch on the output side, 21... LC delay line on the output side, 22...
- Control circuit, 23... Control unit, 25... Operational amplifier, 26... Amplifier, 29... Variable resistance circuit, 30... Control terminal, 31■~31n... Delay circuit, L ...Inductor, C...Capacitor. Issuer: Hitachi Medical Co., Ltd. Figure R 261 Width Figure

Claims (2)

[Claims] (1) A probe with a plurality of transducer elements arranged to transmit and receive ultrasonic waves, and a delay circuit that gives a predetermined delay time to the received signal from each transducer element of this probe. A phasing circuit that adds and outputs the received signals whose phases have been aligned in a delay circuit, a detector that detects the signal phased by this phasing circuit, and an image displaying the output signal from this detector. In the ultrasonic diagnostic apparatus, the phasing circuit uses a variable delay circuit that continuously changes the delay time using an electric signal as an internal delay circuit; The variable delay circuit described above is provided for each signal group formed by giving an arbitrary fixed delay time to each of the received signals from each transducer element and then adding the plurality of signals as a group. An ultrasonic diagnostic device characterized by: (2) The above-mentioned phasing circuit includes a delay circuit that provides a minute delay that changes over time for each received signal from each transducer element of the probe, and also receives the delay time of this delay circuit. 2. The ultrasonic diagnostic apparatus according to claim 1, wherein each channel of the wave signal is independently controlled.