JPH11146492A - Ultrasonic probe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily perform weighting without requiring any considerable addition of a production process. SOLUTION: An aligning member 16 is provided on the front side of a piezoelectric body 14. On this aligning member 16, plural grooves 18 are formed along with the X direction of electronic scanning direction. In Y direction, the amount of grooves 18 is set so as to be gradually increased from the center to the end. Therefore, weighting to sound pressure can be provided from the central part to the terminal part. In comparison with the case of forming grooves on the piezoelectric body 14, production is simplified and no difficulty occurs in wiring.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic probe for transmitting and receiving ultrasonic waves, and more particularly to weighting for transmitting and receiving ultrasonic waves.

[0002]

2. Description of the Related Art Known ultrasonic probes include those used in contact with the body surface and those used by being inserted into a body cavity. The electronic scanning ultrasonic probe has an array transducer composed of a plurality of transducers.
If a transmission signal is supplied while giving a predetermined delay time to all or some of the vibrating elements constituting the array vibrator, so-called transmission focus can be performed. If a predetermined delay time is given to the reception signal and the signals are combined and added, the reception focusing can be performed.

In a conventional ultrasonic probe, an acoustic lens is used to improve the resolution in a direction (slice direction) orthogonal to the direction in which the transducers are arranged. However, there is a limit to the beam convergence effect of this acoustic lens (particularly, the convergence decreases before or far from the focus point). Therefore, weighting is applied to the ultrasonic sound pressure in the slice direction. ing.

As a conventional weighting method, there is a method of forming a plurality of grooves orthogonal to a slice direction with respect to an array transducer. However, there is a concern that this method may affect the vibration characteristics of the vibrator, and that it is generally difficult to form a groove in a hard member such as a ceramic. Further, there is a problem that a device is required to take out the electrode.

[0005] Conventionally, a technique has been proposed in which electrodes to be joined above and below an array transducer are interdigital. However, there is a problem that the electrode shape becomes complicated and the manufacturing cost increases.

The present invention has been made in view of the above-mentioned conventional problems, and has as its object to weight the sound pressure (sensitivity) of an ultrasonic wave without requiring a significant addition of a manufacturing process. is there.

Another object of the present invention is to provide an ultrasonic probe capable of obtaining a good resolution from a short distance to a long distance.

[0008]

To achieve the above object, the present invention provides an ultrasonic probe including a piezoelectric element for transmitting and receiving ultrasonic waves, and an acoustic matching material provided on the piezoelectric element. In the tentacle, at least one groove orthogonal to a weighting direction is formed in the acoustic matching material, and the ultrasonic wave is attenuated by the groove formed in the acoustic matching material.

According to the above configuration, the ultrasonic waves transmitted and received can be attenuated by the grooves formed in the acoustic matching material, and as a result, acoustic weighting can be realized. According to the present invention, the processing for weighting can be easily performed as compared with the processing for weighting the piezoelectric element (piezoelectric body). Also, weighting can be performed without adversely affecting the vibration characteristics of the piezoelectric element. Further, there is no difficulty in wiring. In a preferred aspect of the present invention, a plurality of grooves are formed in the acoustic matching material, and weighting is adjusted by an amount of grooves per unit length in the weighting direction.

[0010] In a preferred aspect of the present invention, the groove is filled with a sound absorbing material having a greater degree of ultrasonic attenuation than at least the matching material. An air gap may be used without filling the groove, but if the groove is filled with a sound absorbing material, sound can be reliably absorbed and the structure is strengthened.

The present invention is applicable not only to an array transducer but also to a simple transducer requiring weighting.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a preferred embodiment of an ultrasonic probe according to the present invention, and FIG. 1 is a perspective view showing a configuration of a main part thereof.

The assembly 10 includes a piezoelectric body 14 for transmitting and receiving ultrasonic waves, a backing material 12 provided on the rear side thereof,
And a matching material 16 provided on the front side of the piezoelectric body 14. The piezoelectric body 14 includes a plurality of vibration elements 14a along the X direction (electronic scanning direction, vibration element array direction) in the drawing.
Is divided into That is, the piezoelectric body 14 forms an array vibrator. The backing material 12 is a member that absorbs unnecessary ultrasonic waves radiated from the piezoelectric body 14 to the back side.

The matching member 16 is a member provided for achieving acoustic impedance matching between the piezoelectric body 14 and a member such as a living body or an acoustic lens. In the present embodiment, a plurality of grooves 18 are formed in the matching material 16 in order to weight the matching material 16 in the Y direction (weighting direction). Each groove 18 is formed parallel to the X direction, and when viewed along the Y direction, the amount of the groove 18 per unit length is set to be gradually larger from the center to its end. That is, the groove 18 is patterned for weighting from the center to the end in the Y direction. The groove 18 may be a gap,
The inside of the groove 18 may be filled with, for example, an epoxy material or a photoresist material having large ultrasonic attenuation. That is, such a member functions as a sound-absorbing material, and thereby actively weights.

In the case of a vibrator having a center frequency of 3.5 MHz, the thickness of the piezoelectric body 14 is about 350 μm,
The thickness of the matching material 16 is about 150 μm.

Since the matching member 16 is softer than the case where special processing is performed on the piezoelectric body 14, the processing is easy. Further, if a special electrode pattern shape or the like is formed on the piezoelectric body 14, wiring becomes difficult. However, according to the processing of the matching material 16, such a problem does not occur.

When the assembly 10 according to the present embodiment is formed, the backing material 12 is adhered to the back side of the piezoelectric body 14 with an adhesive or the like, and then the vibration elements 14a are separated from the piezoelectric body 14. First, cutting is performed using a dicing cutter or the like. Of course, after the matching body 16 is mounted on the front side of the piezoelectric body 14, the cutting may be performed from above using a dicing cutter or the like. In this case, a member similar to the above-described sound absorbing material may be filled in the groove formed by the cutting.

At the stage where the matching member 16 is bonded to the piezoelectric member 14, the groove 1 has a predetermined depth so as not to damage the electrode formed on the upper surface of the piezoelectric member 14 with respect to the matching member 16.
8 are formed. In this case, the matching material 16 is
Although the depth of the groove 18 may be set so as to be completely divided into 16 g, the groove 18 may be formed to be slightly shallower than the thickness of the matching material 16. As described above, the density of the groove 18 and the groove 1
A desired acoustic weighting can be realized by appropriately adjusting the width in the Y-direction of 8.

Next, another embodiment will be described. FIG.
Shows an assembly in which two layers of matching materials 16A and 16B are formed. A backing material 12 is provided on the back side of the piezoelectric body 14, and matching materials 16A and 16B are provided on the front side thereof.
Are provided in order. Grooves 18A, 18B are formed in each of the matching members 16A, 16B in the same manner as in the above embodiment. However, in the example shown in FIG. 2, when viewed in the Y direction, the grooves 18A and 18B are provided alternately.
As a result, a gentler weighting gradient can be formed.

FIG. 3 shows still another embodiment. In this embodiment, a matching member 100 is provided on the front side of the single oscillator. The single vibrator is a circular vibrator, and the matching member 100 is also formed in a circular shape in conformity with its shape. A plurality of grooves 102 are formed in the matching member 100 from the center to the end. Weighting can be performed by this groove in the same manner as in the above-described embodiments. Of course, the groove 10 is formed so that the amount of the groove per unit length increases from the center to the radial direction.
2 patterns are set.

[0022]

As described above, according to the present invention,
The sound pressure (sensitivity) of the ultrasonic wave can be weighted without requiring a large increase in the manufacturing process. Also,
According to the present invention, it is possible to form an ultrasonic probe capable of obtaining good resolution from a short distance to a long distance.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a configuration of a main part of an ultrasonic probe according to the present invention.

FIG. 2 is a perspective view illustrating a main configuration of an ultrasonic probe according to another embodiment.

FIG. 3 is a top view showing a main configuration of an ultrasonic probe according to still another embodiment.

[Explanation of symbols]

10 assembly, 12 backing material, 14 piezoelectric body, 1
6 Alignment material, 18 grooves.

Claims (3)

[Claims] 1. An ultrasonic probe comprising: a piezoelectric element for transmitting and receiving ultrasonic waves; and an acoustic matching material provided on the piezoelectric element, wherein the acoustic matching material is orthogonal to a weighting direction. An ultrasonic probe, wherein at least one groove is formed, and an ultrasonic wave is attenuated by the groove formed in the acoustic matching material. 2. The ultrasonic probe according to claim 1, wherein a plurality of grooves are formed in the acoustic matching member, and weighting is adjusted by an amount of grooves per unit length in the weighting direction. Ultrasonic probe featuring. 3. The ultrasonic probe according to claim 1, wherein the groove is filled with a sound absorbing material having a degree of ultrasonic attenuation that is larger than that of the matching material. Child.