JPS6359697B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in an ultrasonic transceiver device, particularly an ultrasonic transceiver device suitable for diagnosing mammary glands and the like.

For early detection of breast cancer, etc., ultrasound diagnostic equipment that can non-invasively display images of the state of the mammary glands is well known, and in normal cases, a linear electronic scanning probe is used to scan the breast in a circular section. Alternatively, mammary tissue is observed while rotating the probe around the breast. However, this conventional device has a problem in that it is not necessarily possible to obtain high-resolution images.

Therefore, in recent years, a method using reflected waves in a direction perpendicular to the traveling direction of the ultrasound beam, which is different from the above-mentioned pulse echo method, has been studied, and good diagnostic results have been obtained.

FIG. 1 shows this type of conventional wave transmitting/receiving device, in which the ultrasonic beam transmitted from the wave transmitter 10 is focused by driving the gutter-type wave transmitter 10 to form a focal line. Focused at 100. In the conventional pulse-echo method, the transmitter is used as a receiver and the reflected echo is received in the direction opposite to the direction in which the ultrasonic beam travels. It is characterized by receiving echoes reflected in a direction perpendicular to the traveling direction of the ultrasonic beam, and in order to receive the reflected waves, a receiver 12 is provided on the extension of the focal line 100. ,
An echo corresponding to the degree of reflection of the ultrasound beam on the focal line 100 can be obtained. Therefore, by transmitting and receiving waves once, an image signal on the focal line 100 can be obtained, and by mechanically moving this transmitting and receiving device and scanning the focal line 100, an ultrasound image of a desired cross section can be obtained. It has the advantage that information can be obtained, and that high-resolution images can be obtained by focusing the ultrasound beam.

However, even with this improved device, it is necessary to mechanically scan the wave transmitter/receiver device to obtain the desired tomographic image, which results in a long diagnosis time, making it unsuitable for mass examinations, especially for mammary gland examinations. There was a problem.

The present invention was made in view of the above-mentioned conventional problems, and its purpose is to improve the above-mentioned wave transmission/reception method using reflected waves to obtain high-quality tomographic images in a short time required for diagnosis, especially for mammary gland diagnosis. The objective is to provide a suitable wave transmitting/receiving device.

In order to achieve the above object, the present invention transmits an ultrasonic beam that is focused on a focal line a predetermined distance away from a transducer surface formed in a trough shape, and changes the radius of curvature of the transducer surface. It has a planar ultrasound receiver that scans the focal line of the acoustic beam in a direction opposite to the transducer surface, and a wave reception scanning surface that is provided on one extension of the focal line and corresponds to the scanning surface of the focal line. It is characterized by being equipped with an ultrasonic wave receiver.

Preferred embodiments of the present invention will be described below based on the drawings.

FIG. 2 shows a preferred embodiment of the ultrasonic transmitter/receiver according to the present invention, in which a planar ultrasonic transmitter 14
and a linear electronic scanning type ultrasonic receiver 16.

The planar ultrasound transmitter 14 has a trough-shaped transducer surface, and transmits an ultrasound beam focused on a focal line 100 a predetermined distance away from the transducer surface.

FIG. 3 shows the scanning of the focal line 100 by the planar ultrasonic transmitter 14, in which the radius of curvature of the trough-shaped transducer surface is changed electrically or mechanically,
The focal line 100 of the ultrasonic beam transmitted from this transducer surface is scanned so as to move in a direction facing the transducer surface. In this embodiment, the radius of curvature of the transmitter vibrator surface is electrically controlled using the piezoelectric effect. That is, as shown in FIG. 3, when the piezoelectric film is stretched by applying a voltage to the piezoelectric film on the surface of the vibrator with both ends fixed in a curved state, the radius of curvature changes as shown by the broken line in the figure. When the piezoelectric film is contracted, the radius of curvature increases and the focal line 100 moves farther away, as shown by the solid line in the figure. As the piezoelectric film, a piezoelectric polymer material such as PVF ₂ is used, for example. When the radius of curvature of the transmitter vibrator surface is mechanically controlled, the distance l between both ends of the fixed vibrator surface may be mechanically changed, for example, from 74 to 81 mm. As a result, the radius of curvature of the vibrator surface changes, and the focal line 100 can be varied from 50 to 100 mm.

On the other hand, the receiver 16 is formed of a large-diameter linear electronic scanning type ultrasonic receiver provided on one extension of the focal line 100 and has a reception scanning plane corresponding to the scanning plane of the focal line 100. In this example, this receiver has a structure in which an acoustic backing material is provided on the back side of an ultrasonic transducer, and an acoustic lens and an acoustic matching layer are provided on the front side, that is, the receiving surface side of the ultrasonic beam. The receiving scanning plane of the receiver 16 is indicated by reference numeral 200, and the focal line 17
Since this wave reception scanning plane is set corresponding to the scanning plane of The wave receiving transducer located on the extension of the focal line 100 of the beam enters the receiving state, reliably receives the reflected wave of the focal line 100, and electronically performs high-speed scanning without the need for mechanical scanning. This makes it possible to receive reflected waves electronically. Therefore, the time required to obtain one tomographic image can be extremely shortened, and the necessary images can be obtained almost in real time.

Next, a fourth embodiment of a control circuit for controlling the operations of the ultrasonic transmitter 14 and the ultrasonic receiver 16 will be described.
This will be explained based on the diagram.

In the figure, 20 is a frequency dividing circuit, and the oscillator 2
A trigger pulse is output at regular intervals obtained by frequency-dividing the clock pulse output from 2 by a predetermined amount. Then, each time this trigger pulse is output, the transmission driver 24 is driven, excites the vibrator of the ultrasonic transmitter 14, and transmits an ultrasonic beam focused on the focal line 100.

Further, the trigger pulse output from the frequency dividing circuit 20 is input to the address counter 28. This address counter 28 calculates the input trigger pulse and selectively reads out the scanning position of the focal line 100 preset in the ROM 30. The positional information of the focal line 100 read out in this manner is input to a curvature radius control circuit 32 that adjusts the position of the focal line 100 by changing the radius of curvature of the radiator vibrator surface based on this information. In this embodiment, since the radius of curvature of the vibrator surface is electrically adjusted, the control circuit 32 converts the digital information read from the ROM 30 into a voltage and applies it to the piezoelectric film using a D/A converter. is used. In this way, the ultrasonic beam is transmitted from the radiator transducer surface while scanning the focal line 100 toward or away from the radiator every time a trigger pulse is output.

Furthermore, in synchronization with the movement of the focal line 100, it is necessary to align the linear electronic scanning position on the reception scanning surface 200 of the ultrasonic wave receiver with the movement position of the focal line 100. Therefore, the positional information of the focal line 100 read out from the ROM 30 is input to the ultrasonic receiver 16 via the converter 34, and the linear electronic scanning position of the reception scanning surface 200 of the receiver 16 is the focal line 100.
It is selected to correspond to the movement position of 00.

As described above, one electronic scan is performed in which the focal line 100 is scanned in the direction facing the transmitter vibrator surface, and it becomes possible to obtain a high-speed, high-resolution image.

Further, the transmitter 14 and the receiver 16 are fixed to a fixed arm in order to maintain their relative positions,
By mechanically scanning the fixed arm in a direction perpendicular to the electronic scanning direction, desired two-dimensional scanning can be performed and mammary glands etc. can be scanned three-dimensionally.

Further, in the above embodiment, a linear electronic scanning type ultrasonic wave receiver is used as the wave receiver 16, but the present invention is not limited to this. It is also possible to use a container. However, in this case, it is inevitable that the scanning time will be shorter than when using a linear electronic scanning type ultrasonic receiver.

Note that by forming an acoustic matching layer on the vibrator surface of the above-mentioned wave transmitter, it is possible to further improve the wave transmission sensitivity and distance resolution.

As explained above, according to the present invention, the ultrasonic beam transmitted from the transducer surface formed in the shape of a gutter is focused on a focal line, and the focal line is scanned on one extension of the focal line. By providing an ultrasonic receiver with a reception scanning surface that coincides with the plane, it is possible to obtain high-resolution ultrasonic diagnostic images using reflected waves in the direction perpendicular to the focal line. By changing the radius of curvature and continuously scanning the focal line of the ultrasound beam transmitted from the transducer surface in opposite directions of the transducer surface, scanning time is significantly shortened and high-quality images can be obtained in real time. It has the advantage of being obtained. In particular, the present invention is extremely effective when continuously examining mammary glands and the like.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing a conventional ultrasonic transceiver, FIG. 2 is a perspective view of a main part showing a preferred embodiment of the ultrasonic transceiver according to the present invention, and FIG. FIG. 4 is a block diagram showing the control circuit of the apparatus shown in FIG. 2. 14... Planar ultrasonic wave transmitter, 16... Ultrasonic wave receiver, 100... Focal line, 200... Receiving scanning surface.

Claims (1)

[Claims] 1. Transmitting an ultrasonic beam focused on a focal line a predetermined distance away from a transducer surface formed in a trough shape, and changing the radius of curvature of the transducer surface to transmit the ultrasonic beam. A planar ultrasonic transmitter that scans a focal line in a direction opposite to the transducer surface, and an ultrasonic receiver that has a receiving scanning surface that is provided on one extension of the focal line and corresponds to the scanning surface of the focal line. An ultrasonic wave transmitting/receiving device characterized by being equipped with a transducer. 2. The ultrasonic transceiver device according to claim 1, wherein the ultrasonic receiver is a linear electronic scanning type ultrasonic receiver. 3. In the device according to claim 1 or 2, the ultrasonic transmitter is an ultrasonic transmitter that electrically controls the radius of curvature of the transducer surface formed in a trough shape using a piezoelectric effect. An ultrasonic wave transmitting/receiving device characterized by using a wave device. 4. In the device according to either claim 1 or 2, the ultrasonic transmitter uses an ultrasonic transmitter that mechanically controls the radius of curvature of a gutter-shaped vibrator surface. An ultrasonic transceiver device featuring: