JPH0282955A - Ultrasonic probe - Google Patents

Abstract

PURPOSE:To enhance the S/N ratio of a Doppler signal due to a continuous wave by preventing that mechanical leakage and electrical leakage are generated when the continuous wave is transmitted by arranging the third vibrator earthed electrically between the first and second vibrators on a backing material. CONSTITUTION:The third vibrator 18 is arranged between the first and second vibrators 12, 13 on a backing material 11. The third vibrator 18 is electrically earthed to a flexible substrate 14 and vibrated when the transmitted wave from the first vibrator 12 is leaked to be ready to generate potential but, by allowing said potential to flow by the earth and suppressing vibration forcibly, the leakage of the transmitted wave from the first vibrator 12 toward the second vibrator 13 can be reduced.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention particularly relates to an ultrasonic wave generator having a first transducer for continuous wave transmission and a second transducer for both continuous wave reception and pulsed wave transmission and reception. It concerns a sonic probe.

[Conventional technology]

FIG. 5 shows an example of the configuration of a conventional ultrasonic probe.

This ultrasonic probe includes a first transducer 2 on the top surface of a backing material 1 for transmitting continuous waves, and a second transducer 3 for receiving continuous waves and transmitting and receiving pulse waves. and. The first vibrator 2 is a single-piece vibrator, and the second vibrator 3 is an array vibrator. In addition, the first
- A gap 4 with a cutout in the upper surface is provided between the vibrator 2 and the second vibrator 3, so that when the first vibrator 2 transmits a continuous wave, the transmitted wave is caused by the air generated by the gap 4. The layer blocks direct propagation to the second vibrator 3, thereby preventing the second vibrator 3 from vibrating and eliminating mechanical leakage during wave transmission.

[Problem to be solved by the invention]

By the way, in the above-mentioned conventional technology, although the gap 4 is provided between the first vibrator 2 and the second vibrator 3 of the backing material 1, the vibration of the first vibrator 2 is transmitted by air vibration, so that it is not practical. It's not good enough. That is, when transmitting waves from the first vibrator 2,
The actual situation is that the transmitted wave directly leaks to the second vibrator 3 side, causing the second vibrator 3 to vibrate. Furthermore, if the second vibrator 3 vibrates during the transmission of the first vibrator 2, it will adversely affect the signal received by the reflected wave from the first vibrator 2, resulting in electrical leakage.

For this reason, there is a problem that the S/N ratio of the Doppler signal due to the continuous wave deteriorates.

In view of the above circumstances, an object of the present invention is to provide an ultrasonic probe that can improve the S/N ratio of a Doppler signal using continuous waves by preventing mechanical leakage and electrical leakage during continuous wave transmission. Our goal is to provide the following.

[Means to solve the problem]

The above problem can be solved by using a first transducer for continuous wave transmission, a second transducer for both continuous wave reception and pulsed wave transmission and reception, and an ultrasonic probe provided on a backing material. This problem is solved by arranging an electrically grounded third vibrator between the vibrator and the second vibrator.

[Effect]

The present invention utilizes the characteristics of piezoelectric vibrators. That is, a piezoelectric vibrator has the characteristic that when a voltage is applied, the piezoelectric vibrator causes a change in volume (vibrates), and conversely, when the volume is changed, a voltage is generated. Of these, in the latter characteristic, when receiving energy that changes the volume,
If the voltage that should be generated in the vibrator is not generated by grounding it, the volume will not change after all. Therefore, it does not vibrate.

That is, when the first vibrator vibrates and the energy propagates to the third vibrator, the third vibrator converts the energy into electrical energy and flows it to the ground, and the third vibrator does not vibrate. Therefore, no energy is transferred from the third oscillator to the second oscillator. As a result, even if the first vibrator vibrates, the second vibrator is not affected by it.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 to 4. 1 and 2 show a first embodiment of the invention.

The ultrasonic probe of the embodiment includes a first transducer 12 for transmitting continuous waves onto a backing material 11, and a second transducer 13 for receiving continuous waves and transmitting and receiving pulse waves. and is provided.

More specifically, the first vibrator 12 is composed of a single piece of vibrator, and the second vibrator 13 is composed of a plurality of vibrators arranged, both of which are electrically connected to a flexible substrate 14 on which a backing material 11 is attached. connected. A cable 15 drawn out from the device main body (not shown) is connected to the flexible board 14.

The backing material 11 is the first. Second vibrator 12°13
The transducers 12 and 13 are made of a material that has a damping effect that suppresses vibrations of the ultrasonic waves emitted from the transducers 12 and 13 or their reflected waves, and a sound absorbing effect that absorbs the ultrasonic waves from the vibrators 12 and 13.

On the other hand, the first. An acoustic lens 17 is attached to the surface side of the second transducer 12.13 via a matching layer 16 for efficient propagation of ultrasonic waves. I am trying to make it possible to converge.

Therefore, in the embodiment, the third vibrator 18 is located between the first vibrator 12 and the second vibrator 13 on the backing material 11.
is placed.

That is, the third vibrator 18 is disposed between the first vibrator 12 and the second vibrator 13 on the upper surface of the backing material 11, and has the same thickness, width, and length as each of the second vibrator 13. It consists of a plurality of arrayed vibrators formed in the same direction. These dimensions and shapes allow the machining process of the second vibrator 13 to be applied as is. The third vibrator 18 is electrically grounded to the flexible substrate 14, and when the transmitted wave from the first vibrator 12 leaks, it vibrates and tries to generate a potential. By grounding and forcibly suppressing the vibration, it is possible to reduce the leakage of waves transmitted from the first vibrator 12 to the second vibrator 13 side.

In this embodiment, a case is described in which the third vibrator 18 is an array vibrator, since the continuous wave leakage reduction effect increases as the number of vibrators increases. If the third vibrator 18 is grounded, even a single vibrator can produce a certain degree of effect. In this case, it goes without saying that the thickness, width, and length of the single vibrator must be set with consideration given to the vertical and horizontal vibration modes of the vibrator.

In addition, the backing material 11 has the second vibrator 13 and the third vibrator 18 attached thereto, and the backing material 11 has a structure in which the second vibrator 13 and the third vibrator 18 are attached.
The vibrator 12 is constructed to be stronger than the mounted ILB.

In such an ultrasonic probe, during an inspection, when the first transducer 12 transmits continuous wave ultrasonic waves, the transmitted waves are transmitted to the second transducer 1.
Trying to leak to the 3rd side. However, as mentioned above, the third vibrator that is electrically grounded between the first vibrator 12 and the second vibrator 13
Even if the vibrator 18 is placed and the third vibrator 18 directly receives the leaked transmitted wave, the piezoelectric effect of the vibrator will not work, and the vibration will be forcibly suppressed, causing the transmitted wave to be suppressed. Second vibrator 1
Leakage to the third side can be reduced. That is, in other words, the leakage of transmitted waves toward the second vibrator 13 is absorbed and blocked by the third vibrator 18 .

Therefore, as a result of being able to prevent the second vibrator 13 from vibrating due to leakage transmission from the first vibrator 12, the second vibrator 13
Even when receiving the reflected wave from the first vibrator 12, there is no piezoelectric effect (no mechanical vibration is generated).

3 and 4 show other embodiments of the invention.

In this embodiment, the first vibrator 12 is composed of a plurality of vibrators arranged, and two vibrators are used, and they are provided on both sides of the second vibrator 13, respectively. A third vibrator 18 is arranged between the first vibrator 12 and the second vibrator 13, respectively.

By configuring the two first transducers 12 of this embodiment with a plurality of arrayed transducers, the range when transmitting ultrasonic waves can be expanded, and either one of them can be used alternatively or It is controlled so that both waves are transmitted at the same time. Note that when transmitting both waves at the same time, they are both focused in the same direction.

According to this embodiment, in addition to being basically the same as the first embodiment, it is possible to expand the wave transmission range by configuring the first transducer 12 with a plurality of arrayed transducers. It can be detected, and if two of them are used at the same time, the transmitted wave intensity increases accordingly, so it can be detected clearly.

〔Effect of the invention〕

As described above, according to the present invention, the third vibrator electrically grounded between the first vibrator and the second vibrator on the backing material
．． The configuration is such that the third vibrator does not vibrate even if it receives transmitted waves leaking from the first vibrator, and can reduce the leakage of transmitted waves to the second vibrator side. The result is that the vibrator can be prevented from vibrating due to leakage transmission from the first vibrator, and thereby the signal generated when the second vibrator receives the reflected wave from the first vibrator is not adversely affected. , the S/N ratio of continuous wave Doppler signals can be improved.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway overall perspective view showing a first embodiment of the present invention, FIG. 2 is an enlarged perspective view of the first essential part, and FIG. 3 is a partial perspective view showing another embodiment of the present invention. FIG. 4 is an enlarged perspective view of the main part of FIG. 3, and FIG. 5 is a perspective view showing an example of the configuration of a conventional ultrasonic probe. 11... Backing material, 12... First vibrator, 13
...Second vibrator, 18...Third vibrator. Patent applicant Hitachi Medical Co., Ltd. Patent attorney
Masami Akimoto (1 other person) 11: Bazyanbu'ne 1 12: Note 1 FiL action S 13, 2nd 'ffl action) 182 3rd gourd 1)

Claims (1)

[Claims] 1. In an ultrasonic probe in which a first transducer for continuous wave transmission and a second transducer for both continuous wave reception and pulsed wave transmission and reception are provided on a backing material, the first transducer on the backing material and An ultrasonic probe characterized in that an electrically grounded third transducer is disposed between the second transducer and the second transducer.