JPH0551297B2 - - Google Patents

Description

Detailed Description of the Invention [Industrial Field of Application] The present invention relates to a receiver for an ultrasonic diagnostic device, and particularly to a receiver for an ultrasonic diagnostic device, in particular, a receiver for an ultrasonic diagnostic device. The present invention relates to a receiver for an ultrasonic diagnostic apparatus that delays and controls reflected echo signals received by a receiver.

[Prior Art] Ultrasonic diagnostic equipment that emits ultrasonic waves into a subject such as a living body, receives reflected echoes, and displays internal information such as a tomographic image or velocity (Doppler) information as an image is well known. In this ultrasonic diagnostic apparatus, in order to obtain information over a wider range than the transducer width, the ultrasonic beam is angularly deflected and controlled to display information over a sector-like (fan-shaped) range as an image.

3 and 4 show the relationship between the ultrasonic reflected echo and the transducer in the case of sector scanning. For each minute angle, e.g.
Ultrasonic beams are emitted every 0.35 degrees and 0.7 degrees,
When the ultrasonic beam is emitted through the scanning line 100-2 to the scanning line 100-3, scanning for one screen is completed.

When performing deflection scanning in a predetermined angular direction in such sector scanning, the reflected echo wave from the focus point F must be received by all the transducers 10 in the transducer row, as shown in FIG. However, the times at which the reflected echo waves arrive at each vibrator 10 are different.

That is, in the case shown in the figure, the reflected wave from the focus point F reaches the vibrator 10-1 earliest, and reaches the vibrator 10-n the latest. Therefore, in order to align the phases of the signals received by all of the transducers 10-1 to 10-n, it is necessary to sequentially delay the transducer 10 that arrives earlier by the arrival time difference.

For example, as shown in FIG. 5a, the fourth
In the case of the focus point F ₁ corresponding to the figure, the first transducer 10 is given a large delay time (delay amount) shown as D ₁ , and the n/2nd transducer 10 is given D ₂ , For the n-th vibrator 10, a delay time shown as _D3 is given.

Also, as shown in figure b, the focus point
When receiving the reflected wave from F ₂ , the first
As shown in _D1 , the n/2nd in _D2 , and the nth in _D3 , the difference in delay time becomes small.

Furthermore, as shown in Figure c, the focus point
When receiving the reflected wave from F ₃ , the relationship is opposite to that shown in Figure a, and a large delay time shown by D ₃ is given to the n-th vibrator 10.

In this way, the delay time is controlled in order to receive the ultrasonic beam from a predetermined deflection angle direction.
Delay control is performed to focus the beam, and delay control is generally performed for beam deflection and focusing.

FIG. 6 shows a configuration that gives a delay time to a received signal. Conventionally, as shown in FIG.
A distribution circuit 14 is provided to connect the vibrator 10 and the delay line 1.
2 are wired in a matrix and switches are provided at their intersections.

However, this has the problem that the number of wires and switches becomes enormous. In the case of diagram a,
Since the distribution circuit 14 has 20 transducers 10 and 40 taps of the delay line 12, the total number of transducers 10 is 800 (=20×
40) switch is required.

In particular, when performing sector scanning, the smaller the angle between scanning lines when performing angular deflection scanning, the better the quality of the diagnostic image can be obtained.
If the angle between the scanning lines is made smaller and the delay control for angular deflection is finely controlled, the number of delay line taps will increase, and the number of wires and switches will increase significantly.

Conventionally, the vibrator 10 and the delay line 12 are divided into a group adder circuit 16 as shown in FIG. 6b, and this is used to construct a receiver as shown in FIG. 7.

That is, in FIG. 6b, the oscillators 10 and delay lines 12 are divided into four groups, five oscillators 10 and 10 taps of delay lines 12, and the matrix form for the oscillators 10 and delay lines 12 is shown. A distribution circuit 14 is formed therein. Therefore, the total number of switches in the distribution circuit 14 is 200 (=5×10×4), which can be reduced to 1/4 compared to FIG.

Therefore, the receiver shown in FIG. 7 is provided with four group adder circuits 16 that divide the transducer group provided in the sector scanning probe into four groups.
These four group adder circuits 16 give a delay time for focusing to the reflected echo waves obtained by the transducer 10, so that information on a plurality of focal points F set in the distance direction can be obtained. I have to.

Further, a main addition circuit 22 consisting of a main delay line 18 and a main distribution circuit 20 is connected to the group addition circuit 16, and this main addition circuit 22 provides a delay time for determining the deflection angle of the ultrasound beam. The main delay line 18 plays a role separate from the delay line 14 in the group adder circuit 16.

[Problems to be Solved by the Invention] As mentioned above, in the past, the circuit that provides the delay time for focus could be simplified, but the delay line 18 and distribution circuit 20 for angular deflection could be simplified. However, there is a problem in that it cannot be simplified using the method used in the group adder circuit 16 described above.

OBJECT OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and an object of the present invention is to provide an ultrasonic wave that can simplify a circuit that provides a delay time for angular deflection to a received signal. An object of the present invention is to provide a receiver for a diagnostic device.

[Means for Solving the Problems] In order to achieve the above object, a receiver for an ultrasound diagnostic apparatus according to the present invention includes a plurality of transducers that transmit and receive ultrasonic waves, and the plurality of transducers transmit and receive ultrasonic waves. A group of transducers divided into a plurality of groups, a delay line provided for each group to delay a received signal from each transducer, and a tap of the delay line that delays each received signal according to the amount of delay. a plurality of group adder circuits configured with a distribution circuit for distributing to , by connecting the outputs of the group adder circuits at both ends to the inputs of the adjacent group adder circuit and the input of the group adder circuit at the opposite end via a switch, the inputs and outputs of all the group adder circuits are looped. They are connected in a manner similar to each other, and the additively combined received signal is taken out from one of the switching devices.

[Operation] According to the above configuration, the received signals output from each vibrator in the group are delayed and added in the group addition circuit provided corresponding to the group. Here, since the input and output of each group adder circuit are connected in a loop, it is possible to send a received signal output from one group adder circuit to another group adder circuit.

Therefore, depending on the required amount of delay of the received signal, it is possible to perform a desired delay on each received signal by passing it through a plurality of group adder circuits, and in this way, each received signal is delayed. The received signals that have been subjected to this process are finally added and combined via a switch and then taken out.

In this manner, the present invention makes it possible to omit the conventionally used main delay line by connecting the group adder circuit through the switch.

[Embodiments] Hereinafter, preferred embodiments of the present invention will be described based on the drawings.

FIG. 1 shows the configuration of a first embodiment of the present invention. This embodiment has a transducer group consisting of 20 transducers 10, and this transducer group performs sector scanning. There is. There are four group adder circuits 16 (A to D) arranged by dividing this vibrator group into four. Therefore, there are five group adder circuits 16 (=
m/4) from the vibrator 10.

The characteristic feature of the present invention is that in order to completely eliminate the delay line of the main adder circuit used conventionally, the delay line 14 of the group adder circuit 16 also provides a delay time for angular deflection control. delay line 1
4 is used twice.

That is, in the embodiment, each of the four group adder circuits 16 A to D is provided with a switch 24-1, 24-
2, 24-3, 24-4 are provided, and this switch 2
4, the output of the group adder circuit 16 is
The four group adder circuits 16 are connected in a loop.

Therefore, in the group adder circuit 24, for example, A→
The respective outputs are inputted in the order of B→C→D, B→C→D→A, or the opposite order of D→C→B→A, and the arbitrary group adder circuit 16
It is possible to repeat input/output in a loop while giving a predetermined delay time using the starting point as the starting point.

The input signals from the other group adder circuits 16 are supplied to the delay line 12 by the distribution circuit 14 and given a predetermined delay time. This delay time is changed and set depending on the deflection angle of the received ultrasonic beam, and is approximately the same time for the four group adder circuits 16.

This will be explained in the case where, for example, the focus point _F1 is angularly deflected and scanned as shown in FIG. 2. That is, FIG. a shows delay control in the conventional circuit of FIG. 6, in which the delay times of four group adder circuits 16 are sequentially D ₁
D ₂ , D ₃ , and D ₄ , and this delay time is given by the main delay line 18 in FIG. In contrast,
In the case of the embodiment, as shown in Figure b, it is sufficient to provide the delay time _D5 in each group adder circuit 16, and it is understood that relatively simple control is sufficient. be done.

In this way, the delay time of the present invention is determined by the group adder circuit 1
Since 6 delay lines 12 are used, the main delay line 18 provided in FIG. 6 can be omitted, resulting in a reduction to 1/2 compared to the conventional one.

In the above embodiment, a case was explained in which the number of group adder circuits 16 is four, but by setting the number of group adder circuits 16 to about four to eight, delay control for receiving the deflected beam can be performed well. be able to. Furthermore, if the number of transducers 10 that perform sector scanning increases, it is preferable to increase the number of group adder circuits 16 in accordance with the number.

The embodiment has the above configuration, and the overall operation from transmission to reception of ultrasonic waves will be explained below in the first part.
This will be explained based on the diagram and FIG.

First, an excitation signal is supplied to the transducer 10 by a transmission circuit (not shown), and an ultrasonic wave is generated by this excitation signal, and an ultrasonic beam is emitted in a predetermined direction by the transducer group. . Even during this transmission, delay control is performed to radiate the ultrasonic beam in a predetermined direction, and the time for applying the excitation signal to each vibrator 10 is controlled.

Next, reflected echoes in the direction of the emitted ultrasound beam are sequentially received at each predetermined distance (depth), and this is performed by focus control to focus on a predetermined distance.

In other words, in FIG.
After that, the received signal is input to delay lines 12-1 to 12-1 in distribution circuits 14-1 to 14-4.
2-4, and a delay time corresponding to the focus point is given.

When receiving the reflected echo from _{the focus point F 1 in} FIG. They will be received in the order of D.

The output of the group addition circuit 16 of A is supplied to the group addition circuit 16 of B via the switch 24-1, and at the same time a predetermined delay time _D5 is given by the delay line 12-1. It is combined with the received signal input to the group adder circuit 16. Further, the output of the group adder circuit 16 of B is sent to the group adder circuit 16 of C by a switch 2.
4-2, and is given a predetermined delay time _D5 by the delay line 12-2, and at the same time is combined with the received signal input to the C group adder circuit 16.

In this way, the received signals input to the group adder circuits 16 for A, B, C, and D each have a delay time.
The synthesized signal is delayed by D ₅ and is output from the switch 24-4, thereby performing the synthesis shown in FIG.
The phase alignment for receiving the reflected echo of F ₁ is completed.

The input/output order of the group adder circuit 16 changes depending on the angular deflection being scanned, and for example, the fifth
When receiving the reflected echo of focus point F ₂ shown in the figure, proceed in the order of B → C → D → A, and when receiving the reflected echo of focus point F ₃ ,
It is sufficient to perform in the order of D→C→B→A. Of course, since the delay time in the group adder circuit 16 also changes depending on the deflection angle, it is necessary to distribute the delay time in accordance with the deflection angle.

In the embodiment, a transducer group that performs sector scanning has been described, but the present invention can also be applied to the case where angular deflection control is performed using a transducer group that performs linear scanning or convex scanning.

[Effects of the Invention] As explained above, according to the present invention, each group adder circuit is connected in a loop via a switch, so that each received signal from a vibrator in a group is connected to the corresponding group. After delay addition is performed by the group adder circuit provided in the first embodiment, it becomes possible to apply a desired amount of delay to the received signal by using another group adder circuit. Therefore, the conventionally used main delay line can be eliminated, and the apparatus can be simplified.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram showing an embodiment of a receiver for ultrasonic diagnostic equipment according to the present invention, FIG. 2 is an explanatory diagram showing delay time when controlling angle deflection, and FIG. 3 is an explanatory diagram showing sector scanning. , Fig. 4 is an explanatory diagram showing the difference in time for reflected echoes to reach the transducer group, Fig. 5 is an explanatory diagram showing the difference in delay time when controlling angle deflection, and Fig. 6 is a circuit for performing delay control. FIG. 7 is a circuit diagram showing a conventional receiver with a simplified circuit configuration for performing delay control. 10... Oscillator, 12... Delay line, 14... Distribution circuit, 16... Group addition circuit, 18... Main delay line, 20... Main distribution circuit, 22... Main addition circuit.

Claims (1)

[Scope of Claims] 1. A transducer group consisting of a plurality of transducers that transmit and receive ultrasonic waves, and in which the plurality of transducers are divided into a plurality of groups; a plurality of group adder circuits each configured with a delay line that delays a received signal from a child, and a distribution circuit that distributes each of the received signals to the taps of the delay line according to the amount of delay; The output of each group adder circuit in the middle of The inputs and outputs of all the group adder circuits are connected in a loop by connecting the inputs of the adder circuits via a switch, and the received signal that has been added and combined is taken out from any of the switchers. Receiver for ultrasonic diagnostic equipment.