JPS6237979B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an ultrasonic probe used in an ultrasonic diagnostic apparatus. More specifically, the present invention relates to the configuration of a transducer array that constitutes an ultrasonic probe.

Conventional ultrasound probe (hereinafter simply referred to as probe)
is composed of an array of transducers arranged linearly in one dimension. Therefore, a tomographic image obtained from such a probe is one tomographic image obtained by slicing the subject at the position of the probe pressed against the subject. On the other hand, in actual medical examinations, it is common to examine not only a tomographic image of a certain organ of the subject to be examined, but also various parts of that organ. It is true. Therefore, with conventional probes, images have been obtained by appropriately manually moving the probe, but with such means it is not possible to obtain images at relatively accurate slice intervals.

In view of these points, a probe that can accurately shift parallel transducers arranged one-dimensionally (linearly) in parallel using mechanical operations, for example, can obtain tomographic images of organs at 1 mm pitch. This is already known. However, since such a probe requires mechanical elements as an essential requirement, it has not always been satisfactory in terms of small size, light weight, ease of handling, etc. Additionally, during medical examinations, in addition to viewing the organ to be examined in parallel slice planes, it may be easier to diagnose if the organ is sliced 360 degrees at certain angular intervals with the organ as the center. .

The present invention provides a probe in which transducers are arranged in two dimensions and can obtain a tomographic image sliced 360° at a certain angle step around a certain point.

FIG. 1 is a diagram showing an embodiment of a probe according to the present invention. In Fig. 1, small circles indicate the elements of the vibrator (hereinafter simply referred to as vibrating elements), and ~
represent each vibrator group arranged in an array. That is, although the probe shown in FIG. 1 has six transducer arrays arranged radially, the present invention does not limit the number of transducer arrays to six based on this description. As shown in FIG. 1, the vibrator array is an array of, for example, 64 vibrating elements, and the other vibrator arrays are similar. Each individual transducer array has a configuration similar in principle to a conventional linear array. For example, FIG. 3 is an example of a conventional probe, mainly showing a transducer array. In FIG. 3, 1 is a vibration element.

The probe shown in FIG. 1 constructed as described above operates as follows. For example, the center O of the transducer array shown in FIG. 1 is applied to an organ to be examined. The transducer array is driven to obtain a tomographic image at this angle on a cathode ray tube (not shown). Next, by driving the transducer array while the probe remains in contact with the affected area, another tomographic image that forms a certain angle (30° in the case of the probe in Figure 1) with the previous tomographic image is displayed on the cathode ray tube. can be obtained. A similar operation is then performed with the transducer array to obtain images cut at angles of 30° steps on the cathode ray tube. The six tomographic images obtained in this way were obtained with the probe fixed to the affected area, so the six tomographic images had accurate slice angles centered on the affected area. Not only that, but six images can be obtained with the probe fixed, so the screen does not shake and is easy to operate.

FIG. 2 is a diagram showing another embodiment of the probe according to the present invention. In the probe of FIG. 1, the transducer elements of each transducer array are arranged at equal intervals, and as a result, the obtained tomographic image has good image quality with uniform scanning line intervals. However, as is clear from Figure 1, detailed information can be obtained from the center of the image, where many transducers are concentrated, but at the outer periphery, the transducer array is arranged radially. Therefore, the arrangement density of the vibrating elements becomes sparse. Therefore, the slice interval becomes wide in the outer circumference of the affected area, making it impossible to examine the area in detail. The probe shown in FIG. 2 is designed to improve this point, and has vibrators arranged uniformly in a plane. Although FIG. 2 shows an example in which the vibrators are arranged concentrically at equal intervals as a means for uniformly dispersing the particles, the arrangement is not limited to this arrangement.
It is sufficient that the vibrating elements are uniformly distributed over the entire plane. In the vibrators arranged in this way, as shown in FIG.
...to form. In Fig. 2, the transducer elements constituting each transducer array are not arranged at equal intervals, so the image quality of the tomographic image obtained from one transducer array is different from that of the probe in Fig. 1. Inferior to the obtained tomographic image. However, since the transducer elements are uniformly distributed over the entire plane, the transducer array, etc. can be installed at minute angles, and therefore, when obtaining tomographic images over a 360° angle, All of them have uniform image quality, and have the advantage of being able to obtain tomographic images at delicate angles that cannot be obtained with the probe shown in FIG.

FIG. 4 is an example of a drive circuit for driving the probe shown in FIG. 1. In FIG. 4, P is a pulse oscillator, and A ₁ to _{A 8} are delay lines, which have the function of delaying the pulse input from the pulse oscillator P by a predetermined time and outputting it. B ₁ to B ₈ are transducers, M ₁ is a multiplexer, and in Fig. 4, 8 contacts are selected from 64 contacts and turned on by the control signal SGO, and the pulses from the pulse oscillator P are transmitted to the next stage. Introduced into multiplexer. i.e. the multiplexer
_M1 is further connected to 64 multiplexers shown below. m ₁ to _{m 64} are the multiplexers, and in FIG. 4, each multiplexer receives the control signal.
One line point is selected from among the six contacts by SG ₁ to _{SG 64} and the input pulse is applied to the vibrating element. That is, six vibration elements are connected to each multiplexer. C is a vibration element, which corresponds to the number of each element given in FIG. That is, the vibrating element C1-1 in FIG. 4 corresponds to the element number 1-1 constituting the vibrator array in FIG. 1, and the vibrating element C2
-1 corresponds to element number 2-1 constituting the vibrator array in FIG. In this way, the fourth
As shown in the figure, the multiplexers m ₁ to _{m 64} include the first
All the vibrating elements shown in the figure are connected.

The apparatus shown in FIG. 4 constructed as described above operates as follows. The pulses generated by the pulse oscillator P pass through delay lines A ₁ to _{A 8} into groups of eight pulses each having an appropriate time interval, and are sent to the multiplexer M ₁ via each transducer B ₁ to B ₈ . be introduced. In multiplexer M ₁ , the control signal
By the function of SGO, the 8 input pulses are converted into 8 pulses.
Introduced to two next-stage multiplexers. For example, if these eight multiplexers are designated as m ₁ to _{m 8} , each of these multiplexers receives control signals SG ₁ to
Due to the action of SG ₈ , for example, the vibration element number C1-
1, C1-2, C1-3, . . . C1-8 can be controlled to apply pulses. The pulses applied to the eight transducer elements have an appropriate time interval relationship as described above, and the ultrasonic waves transmitted from the eight transducers are ultrasonic waves with a certain depth of focus. Becomes a beam.

When the next pulse is generated from the pulse oscillator P, the multiplexers _M1 and _m1 to _m64 and the control signals _SG0 to
Vibrator C1-2, C1-3, C1- by SG ₆₄
4, . . . By applying a pulse to C1-9, an ultrasonic beam can be obtained in the same manner as described above. In this way, all the vibrating elements constituting the vibrating element array shown in FIG. 1 are driven one after another, and as a result, one tomographic image can be obtained on the cathode ray tube.

The operations described above are similar to those for obtaining one tomographic image using a conventional probe, but when the next pulse is emitted from the pulse oscillator P, the multiplexers M ₁ and m ₁ to _{m 64} and the control signal The transducer arrays are sequentially driven by SG ₀ to SG ₆₄ in the same manner as described above, and tomographic images can be easily obtained over an angle of 360°.

In FIG. 4, the delay line is described as having eight elements, and the number of vibrating elements constituting one vibrator array is 64, but this description does not limit the number of elements.

The means for driving the probe shown in FIG. 1 has been described above, but the driving of the probe shown in FIG. 2 can also be easily inferred from the above description, so a description thereof will be omitted.

As described above, according to the present invention, the center of the probe, which is composed of two-dimensionally arranged transducers, is pressed against the affected area, and while the probe is fixed at that position, tomographic images are obtained by slicing the affected area at various angles. Since the image can be obtained with the probe fixed, there is no blur and the relative slice angle is accurate. Furthermore, since images of organs sliced from various angles can be obtained one after another, it is possible to visualize a three-dimensional image of the organ in one's mind, and for example, to understand the three-dimensional size of a gallstone.

[Brief explanation of the drawing]

FIG. 1 shows one embodiment of the probe according to the present invention;
The figure shows another embodiment of the probe according to the present invention, FIG. 3 shows an example of a conventional probe, and FIG. 4 shows a circuit for driving the probe shown in FIG. 1. ~... Transducer array, P... Pulse oscillator, _A1 to _A8 ... Delay line, _B1 to _B8 ... Transducer, _M1 , _m1 to _m64 ... Multiplexer, C
1-1 to C1-64... Vibration element.

Claims (1)

[Scope of Claims] 1. In an ultrasonic probe equipped with a plurality of transducer arrays each having a plurality of transducer elements arranged in a straight line, each transducer is The arrays are arranged on a plane at intervals of a certain angle step, and one transducer array is selected from a plurality of transducer arrays for each scan to transmit ultrasound. Features of ultrasonic probe.