JPS6375660A - Ultrasonic probe - Google Patents

Abstract

PURPOSE:To easily adjust the depth of an observation position, by mounting a partition wall membrane propagating a sonic wave to the tip part of a medium container and arranging a liquid medium in a sonic wave propagative manner to the sonic propagating direction of a sonic wave lens part by the medium container and the partition wall membrane. CONSTITUTION:A liquid medium 26 is stored in the space formed by a medium container 24 and a partition wall membrane 22, and a sonic lens 16 is provided so as to be immersed in the medium 26 to allow the medium container 24 to slide with a probe main body 14 to make it possible to adjust the depth of the liquid medium 26. When sonic wave beam 20 is generated in the probe main body 14 by the high frequency electric signal applied to a piezoelectric body 12 from a high frequency transmitter 10, said sonic wave beam 20 propagates toward the sonic lens 16 provided to the tip of the probe main body 14. Since the sonic wave lens 16 is immersed in the medium 26 and the space between the partition wall membrane 22 and a specimen 30 is filled with a converging medium, the sonic wave beam 20 is converged to a focus by there elements. By using two liquid medii 18, 26, the minute displacement of the focus becomes possible.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an ultrasound probe, and particularly to an ultrasound probe suitable for an ultrasound microscope.

[Conventional technology]

In recent years, it has become possible to generate ultra-high frequency sound waves ranging from several hundred megahertz to one gigahertz, so the length of the sound waves in water is several microns. Therefore, it has become possible to obtain high-resolution ultrasound beams. The ultrasonic beam is focused by a sonic lens having a predetermined focus, oscillated toward the sample 1ζ to be observed, and the reflected and transmitted sound waves are detected to observe the sample. More specifically, as shown in FIG. 4, a high-frequency electric signal applied from a high-frequency transmitter 10 to an electroacoustic transducer 12 (hereinafter simply referred to as a piezoelectric material) is transmitted to a probe body 14 made of a sound wave propagation medium.
It generates ultrahigh frequency sound waves, or ultrasonic waves. The acoustic beam 20 generated in this way is transmitted to the probe main body 1.
The sound beam 20 reaches a spherically formed acoustic lens 16 on the end face of the beam 20, and the acoustic lens 16 and the focusing liquid medium 18 in which it is immersed form an effective concave shape, whereby the acoustic beam 20 is converged to a focal point F. be done. Note that the piezoelectric body 12 is made of a zinc oxide piezoelectric thin film, and the probe body 14 is made of sapphire, fused silica, or the like, and
Water is used as the focusing liquid medium 18.

In this way, the acoustic beam 20 is focused and oscillated on the sample 30, and the ultrasonic waves reflected, scattered, and transmitted by the sample 30 are detected to obtain information reflecting the elastic properties of the sample 30. Note that in order to obtain the information at an arbitrary depth of the sample 30, the probe body 14 and the sample 30 must be
By changing the distance between the
It is necessary to position this.

[Problem that the invention seeks to solve]

In the prior art, the distance between the probe body 14 and the sample 30 was adjusted directly using a screw mechanism.

Therefore, there is a limit to minute changes, and sample 3
Not enough consideration was given to minute adjustments in the 0 depth direction.

An object of the present invention is to provide an ultrasonic probe in which minute distance adjustment between the probe body and a sample, that is, adjustment of the observation position depth, can be easily performed.

[Means for Solving the Problems] The above object is to provide a medium container which is slidably installed on the sonic lens side of the probe main body so as to protrude beyond the tip of the sonic lens, and which contains a liquid medium therein. This can also be achieved by providing a partition wall means in which a sound wave can propagate and seals the liquid medium at a sound wave propagation position in the medium container.

[Effect]

A plurality of liquid media having different sound propagation velocities are arranged in the sound wave propagation direction of the sound wave lens portion in the probe body by the medium container and the partition means so that the sound waves can propagate, and the medium container is placed relative to the probe body. This was done so that the depth of each of the liquid media could be changed by adjusting the movement, thereby finely adjusting the focal position of the sound wave convergence.

〔Example〕

Hereinafter, one embodiment of the present invention will be described with reference to FIGS. 1 to 3 1ζ. In the same part, the same reference numerals as in the conventional example indicate the same members. Reference numeral 24 is slidably installed on the sonic lens 1G side of the probe body 14, and its tip is a medium container that protrudes beyond the sonic lens 16.
4, the tip protrusion amount can be finely adjusted by, for example, a screw mechanism. Further, a partition membrane 22 capable of propagating sound waves is attached to the tip of the medium container 24. Therefore, the medium container 24 and the partition membrane 22 allow the liquid medium 26 to be stored therein by immersing the sonic lens 16 therein, and the medium container 26 can be slid relative to the probe body 14. The liquid medium 26
The depth can be adjusted.

In such a configuration, the high frequency ii! applied from the high frequency oscillator 10 to the piezoelectric body 12! A sound beam 20 is generated within the probe body 14 by the air 4g. The sound wave beam 20 then propagates toward a sound wave lens 16 provided at the tip of the probe body 14. The sonic lens 16 is immersed in the focusing medium 26, and the space between it and the sample 30 is filled with the IC conduit focusing medium 18 through the partition membrane 22.
These focus the acoustic beam 20 to a focal point F. The focusing medium 181ζ is the same as the conventional example M. Water is used in J, and.

In Kato Yomatsu 526, there is a liquid with a different speed of sound from water in 111,
For example, ethyl alcohol is used. By the way, the 14th speed of water is about 1500 m7/sυ, and the speed of ethyl alcohol is about 1200 m/s. As mentioned above, the partition membrane 221
Therefore, two liquid media having different sound velocities are provided. By using these two liquid media having different sound velocities, it is possible to make a minute displacement of the focal point F in the depth direction. That is, as mentioned above, the sound speed of the focusing medium 18 is about 1500 m/s, and the sound speed of the focusing medium 26 is about 1200 m/s, so the difference in refraction ratio between the two is 1-1.
200/1500=0.2, and a fine displacement adjustment of about 5 times is possible. As a result, as shown in FIG. 2, the focal point F of the acoustic beam 20 focused by the focusing medium 26 and the device 8 is made to coincide with the surface of the sample 30, and then, as shown in FIG. When is displaced by a dimension H compared to the state shown in FIG. 2, the focal position changes by Δh due to the sound speed difference between the focusing media 18 and 26. Note that the above H and Δh have a relationship as shown in the following equation.

That is, Δh→0,2H Therefore, since the focal point F can be adjusted by a minute displacement of about 115 times the dimension H, the focal point F can be easily finely adjusted in the depth direction. Further, in the above structure, the medium container 24 provided with the partition membrane 22 is fitted into the probe main body 24 so as to be movable in one direction, and is attached so that the amount of movement thereof can be adjusted in the sliding direction. This is a much simpler configuration than the previous configuration, and can be finely adjusted.

〔Effect of the invention〕

As explained above, according to the present invention, the observation position depth can be easily finely adjusted.

[Brief explanation of the drawing]

FIG. 1 is a side view showing an embodiment of the ultrasonic probe according to the present invention, FIGS. 2 and 3 are side views showing the focus adjustment state of the ultrasound probe of FIG. 1, and FIG. FIG. 2 is a side view showing a conventional ultrasound probe. 14... Probe body, 16... Sonic lens, 18, 26... Liquid medium, 20...
... Sound wave beam, 22 ... Septum membrane, J of exit surface
O ΔI Prisoner 2 (αn
(B-procedural amendment (method) Display outside the vehicle Patent Application No. 219486 of 1988 Name of the invention
Manufacturer's agent A simple amendment to the column for the detailed description of the invention and the same cause in the specification subject to person's amendment. Contents Explanation column and drawing 1,
"Fig. 4" on page 2, line 8 of the specification is corrected to "Fig. 3." 2. "Figures 1 to 3" on page 4, line 14 of the specification are corrected to "Figures 1 and 2." 3. Correct "probe body required" on page 4, line 19 of the specification to "probe body 14". 4. Correct "medium container a" on page 5, line 5 of the specification to "medium container sae." 5. "Figure 2" on page 6, line 10 and line 13 of the specification is corrected to "Figure 2 (a)". 6. Change “Figure 3” on page 6, line 12 of the specification to “Figure 2 (b)”
)” is corrected. 7. Page 7, line 11 to line 14 of the specification shall be amended as follows. FIG. 3 is a side sectional view showing a focus adjustment state of the ultrasound probe, and FIG. 3 is a side view showing a conventional ultrasound probe. 8. Amend the drawings as per the attached appendix.

Claims (1)

[Claims] 1. An ultrasonic probe in which a sonic lens with a predetermined focus is formed at one end of the probe body made of a sound wave propagation medium, and a piezoelectric body is provided at the other end to generate a sound beam toward the sonic lens. A medium container is installed on the sound wave lens side of the probe main body so as to protrude beyond the sound wave lens portion, and a medium container containing a liquid medium is installed therein, and a medium container is installed at the sound wave propagation position of the medium container. 1. An ultrasonic probe characterized by being provided with a partition wall means that allows propagation of water and seals a liquid medium.