JPS5838541A - Ultrasonic wave transmitting and receiving apparatus - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

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 gland tissue is observed while rotating the probe around the breast.

However, with this conventional device, there was a problem in that it was not always 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 pulse echo method mentioned above, has been developed. has been studied and good diagnostic results have been obtained.

FIG. 1 shows a conventional wave transmitting/receiving device of this type, in which the ultrasonic beam transmitted from the wave transmitter 10 is focused by exciting and driving the gutter-type wave transmitter 10. It is focused at line 100. In the conventional pulse-eco 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, but in this improved method, The characteristic is to receive 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 o, and 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 - times, 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, ultrasound image information of a desired cross section can be obtained. It also has the advantage that a high-resolution image can be obtained by focusing the ultrasound beam.

However, even with this improved device, it is still necessary to mechanically scan the transceiver device in order to obtain the desired tomographic image, resulting in longer diagnostic times.
゛ In particular, 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. The object of the present invention is to provide a wave transmitting/receiving device particularly suitable for mammary gland diagnosis.

In order to achieve the above object, the present invention transmits an ultrasonic beam focused on a focal line a predetermined distance away from a transducer surface formed in a tub shape, and changes the radius of curvature of the transducer surface. It has a planar ultrasonic transmitter 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 transceiver according to the present invention, which is composed of a planar ultrasonic transmitter 14 and a linear electronic scanning ultrasonic receiver 16. .

The planar ultrasonic wave transmitter 14 has a transducer surface formed in a tub shape, and transmits an ultrasonic beam focused on a focal line 100 that is a predetermined distance away from the transducer surface.

FIG. 3 shows the focal line 10 caused by the planar ultrasonic transmitter 14.
0 scanning is shown, the radius of curvature of the trough-shaped transducer surface is electrically or mechanically changed, and the focal line 100 of the ultrasonic beam transmitted from this transducer surface is made to face the transducer surface. Scan to move in the direction. 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 becomes smaller, its focal line 100 moves to the front, and the piezoelectric film contracts, as shown by the solid line in the figure,
The radius of curvature is a dog, and its focal line 100 moves far away.As the piezoelectric film, a piezoelectric polymer material such as PVF2 is used, for example.

In addition, when the radius of curvature of the transducer surface of the transmitter is mechanically controlled, the distance l between both ends of the fixed transducer surface is determined.

For example, it may be mechanically changed from 74 to 81 wR.

As a result, the radius of curvature of the vibrator surface changes, and the focal line 100
can be varied from 50 to 100 degrees.On the other hand,
The receiver 16 is formed from a large-diameter linear electronic scanning type ultrasonic receiver provided on one extension of the focal line 100 and having a reception scanning plane corresponding to the scanning plane of the focal line 100. This receiver has a configuration in which an acoustic backing material is provided on the back side of the 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 wave receiver 16 has a wave receiving scanning surface indicated by reference numeral 200, and this wave receiving scanning surface is set corresponding to the scanning surface of the focal line 100, so that the electronic scanning of the transmitter 14 described above is possible. l of the receiver 16 by synchronous control with
If J near electronic scanning is controlled, the receiving transducer located on the extension of the focal line 100 of the ultrasonic beam will be in the receiving state, and the reflected wave of the focal line 100 will be reliably received, and the mechanical It becomes possible to electronically receive reflected waves at high speed without requiring extensive scanning. 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, one embodiment of a control circuit for controlling the operations of the ultrasonic transmitter 14 and the ultrasonic receiver 16 will be described with reference to FIG. 4.

In the figure, 20 is a frequency divider circuit, which outputs a trigger pulse at fixed time intervals obtained by dividing the clock pulse output from the oscillator 22 by a predetermined amount. and,
Every 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 outputted from the frequency dividing circuit 20 is inputted to the address counter 28. This address counter 28 calculates the input trigger pulse and stores it in the ROM 30.
Selective reading of the scanning position of the focal line 100 that is preset in the memory is performed. The position information of the focal line 100 read in this manner is input to a curvature radius control circuit 32 that changes the radius of curvature of the radiator resonator surface and adjusts the position of the focal line 100 based on this information. . In this example, since the radius of curvature of the vibrator surface is electrically adjusted, the control circuit 32 converts the digital information read from the ROM 3Q into a voltage and applies it to the piezoelectric film. In this way, an 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.

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

As described above, it is possible to perform a single electronic scan in which the focal line 100 is scanned in the direction facing the transmitter oscillator surface, and to obtain an image with high speed and high resolution. By fixing the transmitter 14 and the receiver 16 to a fixed arm in order to maintain their relative positions, and mechanically scanning the fixed arm in a direction perpendicular to the electronic scanning direction,
It becomes possible to perform a desired two-dimensional scan and three-dimensionally scan the mammary glands.

Further, in the above embodiment, a linear electronic scanning type ultrasonic receiver was used as the receiver 16, but the receiver 16 is not limited to this.
It is also possible to use a mechanically scanned ultrasonic receiver that is scanned in synchronization with the movement of 100.

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 transmitter described above, it is possible to further improve the wave transmission sensitivity and the distance resolution.

As explained above, according to the present invention, the ultrasonic beam transmitted from the transducer surface formed in the shape of a bucket 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 a high-resolution ultrasound diagnostic image 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 ultrasonic beam transmitted from the transducer surface in the opposite direction of the transducer surface, the scanning time can be significantly shortened and high-quality images can be produced in real time. It has the advantage that images can be 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. FIG. 4 is a block diagram showing the control circuit of the device shown in FIG. 2. 14... Planar ultrasonic wave transmitter I6... Ultrasonic wave receiver 100... Focal line 200... Receiving scanning surface. Applicant Aloka Co., Ltd. Sai2 Zuga 3

Claims (1)

[Scope of Claims] (1) Transmitting an ultrasonic beam focused on a focal line a predetermined distance from a transducer surface formed in a bucket shape, and changing the radius of curvature of the transducer surface to generate the ultrasonic waves. A planar ultrasonic transmitter that scans the focal line of the beam in a direction opposite to the transducer surface, and an ultrasonic wave transmitter 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 comprising a sonic wave receiver. (2. The ultrasonic transceiver device according to claim (1), characterized in that the ultrasonic receiver is a linear electronic scanning type ultrasonic receiver. (3) Claim (1) In the apparatus described in any one of ranges (11 and (21), the ultrasonic transmitter is an ultrasonic transmitter that electrically controls the radius of curvature of the transducer surface formed in a tub shape using a piezoelectric effect. (4) In the device according to any one of Claims +1> and !21, the ultrasonic transmitter includes a transducer surface shaped like a tub. An ultrasonic wave transmitting/receiving device characterized by using an ultrasonic wave transmitter that mechanically controls the radius of curvature of.