JPH05200026A - Manufacture of ultrasonic probe used in coelom - Google Patents

Abstract

PURPOSE:To manufacture efficiently economically an electronic scanning system ultrasonic probe. CONSTITUTION:While a piezoelectric film 4 is mounted on a first flexible base plate 1 having a plurality of signal transmitting member, a second flexible base plate 5 having an earth member is mounted and a protective base plate 9 having a conductive layer 8 is mounted on the piezoelectric film 4 and the second flexible base plate 5 to form a planar laminated member. Then, the laminated member is bent such that a plurality of signal transmitting members are bent along the outer periphery to form a cylindrical sheath 11 in the method for manufacturing an ultrasonic wave probe used in the coelom.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing an ultrasonic probe in a body cavity used for ultrasonic diagnosis in the body cavity.

[0002]

2. Description of the Related Art An ultrasonic transducer is provided at the tip of an insertion portion to be inserted into a body cavity, and ultrasonic scanning is performed while irradiating a subject with an ultrasonic beam. There are various types. Among them, the one adopting a scanning method called an electronic radial method is provided with a plurality of divided transducer arrays and controls the drive timing of each transducer array by applying an electrical delay to form an ultrasonic beam. It was done. Japanese Patent Publication No. 63-14623 discloses an ultrasonic probe in a body cavity that employs this method.

A similar scanning method is called a mecha-radial method. For example, to explain the configuration applied to an ultrasonic endoscope, a movable part that mechanically rotates these ultrasonic transducers is provided inside the tip of the endoscope provided with a plurality of ultrasonic transducers. Then, the ultrasonic beam is formed while rotating the ultrasonic vibrator in the outer peripheral direction of the insertion portion. However, the mecha-radial type has many problems as compared with the electronic radial type. That is, in the electronic radial type, since the ultrasonic transducer is arranged along the outer surface of the endoscope, a cavity can be formed in the central axis portion of the endoscope. A channel for inserting a light guide, a video signal line, forceps or the like can be provided in this cavity.

Therefore, it becomes possible to obtain an image in the direct viewing direction which enables endoscopic observation, which is extremely advantageous for an endoscope when it is inserted into a body cavity and when it is diagnosed, and medical advantages are great. Further, since the electronic radial type does not have a movable part at the tip of the insertion part, the probability of causing mechanical failure or malfunction is low. The mecha-radial type is inferior in these points, and further requires a transducer protection cover for protecting the movable end portion and an ultrasonic transmission medium for acoustically coupling the ultrasonic transducer and the protective cover.
This ultrasonic transmission medium also causes multiple echoes due to reflection of the ultrasonic beam and a decrease in sensitivity due to attenuation.

[0005]

On the other hand, the above-mentioned electronic radial system also has a problem. That is, the ultrasonic probe of the electronic scanning type such as the electronic radial type is difficult to manufacture and the manufacturing cost is high. As disclosed in JP-A-58-190756, the ultrasonic probe has a large number of ultrasonic vibrators arranged at the tip of the probe, but each ultrasonic vibrator must be connected with a signal transmission line. ..

For that purpose, it is necessary to provide an ultra-fine multi-core cable in succession to the ultrasonic transducer or to provide a multiplexer for switching and driving several signal lines to each ultrasonic transducer at the probe tip. .. However, due to the property of the ultrasonic probe in the body cavity, the above-described configuration that causes an increase in the length of the distal multi-rigid portion and an increase in the diameter of the endoscope insertion portion is extremely inconvenient. In order to eliminate this inconvenience, an ultrasonic probe is manufactured by applying a precision processing technique, but this has the disadvantage that the product cost increases.

The present invention is proposed to solve the above-mentioned problems, and provides a method for manufacturing an ultrasonic probe in a body cavity capable of manufacturing an electronic scan type ultrasonic probe such as an electronic radial type with high production efficiency and at low cost. The purpose is to do.

[0008]

In order to achieve the above-mentioned object, the present invention provides a method for producing an ultrasonic probe in a body cavity having an array of ultrasonic transducers at the tip of an insertion portion, for transmitting at least a plurality of signals. A flexible substrate having a member, a piezoelectric film, and a protective substrate are laminated to form a flat plate-shaped laminated member, and then the laminated member is curved so that the plurality of signal electrical component members are along the outer periphery to form a cylindrical sheath. This is a method for manufacturing an ultrasonic probe in a body cavity to be formed.

[0009]

In this way, since the laminated member is curved to form the cylindrical sheath, it is not necessary to provide a large number of wires for supplying signals to the ultrasonic transducer, and the manufacturing process can be simplified. Moreover, since the piezoelectric film, the flexible substrate, and the protective substrate are laminated and formed in a flat plate state, the manufacturing is easy and the manufacturing cost can be suppressed.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a process explanatory diagram of a manufacturing method according to a first embodiment of the present invention. First, the first flexible substrate 1 having a plurality of signal transmission members is prepared. The substrate is formed of an insulating resin such as polyimide, and a signal transmission member having a lead portion 2 and a positive electrode portion 3 continuous to the end of the lead portion 2 is formed on the substrate by etching. Further, the first flexible substrate 1 is formed so that the aspect ratio corresponds to the outer peripheral length and the insertion portion length of the ultrasonic probe, respectively. Since the first flexible substrate 1 is curved in a cylindrical shape in a later step to form a sheath, bending rigidity as an ultrasonic probe is secured by joining a second flexible substrate described later.

Next, the piezoelectric film 4 is fixed to the first flexible substrate 1 near the positive electrode portion 3 with an adhesive. The piezoelectric film 4 is a polymer piezoelectric film made of PVDF, for example. Further, the second flexible substrate 5 is fixed to the first flexible substrate 1 near the lead portion 2 via an adhesive so as to protect the lead portion 2. The second flexible substrate 5 has a sandwich structure in which a copper foil 7 for forming a common ground wire is made of an insulating resin 6 such as polyimide in a partially exposed state.

Next, a protective substrate 9 provided with a conductive layer 8 for electrically connecting the piezoelectric film 4 and the copper foil 7 and forming a common negative electrode on the resin surface is fixed on the piezoelectric film 4 via a conductive adhesive. To do. The protective substrate 9 also functions as an acoustic matching layer with the subject. Joining the above-mentioned constituent members into a flat plate-shaped laminated member can be performed reliably and easily without any difficulty in manufacturing. FIG. 1B is a perspective view showing a state in which the laminated member is formed.

Next, before the adhesive between the constituent members of the laminated member is cured, the first flexible substrate 1 is curved inside and the plurality of signal electric component members are curved along the outer periphery. , The displacement portion 10 generated between the inner surface and the outer surface is cut (FIG. 1C), and the end faces in the bending direction are welded to each other or bonded with an adhesive or the like to form the cylindrical sheath 11 (FIG. 1D). ). In addition, when an adhesive is used for bonding the respective constituent members in the above steps, a thermosetting adhesive is used, and when the bonding is performed by applying heat in the final step of FIG. The effect is that there are no restrictions.

In this embodiment, since the cylindrical sheath is formed in this manner, the hollow cylinder 12 can be used as a space for disposing other members. That is, a light guide for certifying the inside of a body cavity, an image guide for transmitting an optical image, a transmission cable for a video signal captured by a solid-state image sensor, a channel for inserting a treatment tool such as forceps into the body cavity, It is possible to insert a built-in object such as tubes (neither shown) for supplying air and water into the body cavity into the cylindrical hollow 12.

When the various built-in components 13 are inserted into the cylindrical hollow 12, there is a resistance with the inner surface of the sheath 11 when they are directly inserted, and there is a built-in component sliding resistance when bending while being used as an ultrasonic probe. There is a risk of bending damage. Therefore, as shown in FIG.
It is effective to provide a thin-walled tube 14 formed of a material having a good slipperiness such as Teflon between the thin tube 14 and.

Needless to say, what is disposed in the hollow cylinder 12 is not limited to the built-in components related to the endoscope. For example, an integrated circuit for amplifying a received ultrasonic signal (echo) can be mounted. That is, the ultrasonic beam reflected by the subject is received by the piezoelectric film and converted into an electric signal, but its signal level is extremely small, and this weak signal remains the lead portion 2
When transmitted over a long distance of several meters, there is a risk of being affected by noise such as external electromagnetic waves. Therefore, it is extremely effective to provide an integrated circuit for signal amplification at the tip of the ultrasonic probe and amplify the signal before transmission.

FIG. 3 shows a second embodiment of the present invention. Also in this embodiment, each component is laminated in the same manner as in the first embodiment to form a flat plate. Moreover, in this embodiment, the planar shape of the laminated member is formed into a key shape as shown in FIG. 3A. The laminated member 15 includes a vibrator portion 16 and a belt portion 1.
In order to form a cylindrical sheath by bending it, the transducer part 16 is first wound around a flexible shaft sheath 18 such as Teflon prepared in advance as shown in FIG. 3B. Next, the band portion 17 is sequentially wound in a spiral shape. Then, the heat-shrinkable tube 19 is put on and heated.

In the sheath formed by following these steps, the cylindrical hollow 12 is used as a space for disposing an endoscope built-in object as in the first embodiment. The present embodiment configured as described above has the same effects as the first embodiment,
Even if the end face 17a of the band 17 that is not joined even if it is bent while the ultrasonic probe is being used is directly overlapped with or separated from each other, a direct force is applied to the lead part built in the band 17. Can be prevented. That is, the first
In the examples, when the ultrasonic probe was curved, shear stress was generated on the multilayered surfaces, the laminated surfaces might be peeled off, and cracks might be generated on the flexible substrate to break the lead portions.

FIG. 4 shows a laminated member according to the third embodiment of the present invention. In this embodiment, the ultrasonic wave transmitting member 20 is provided on the surface of the second flexible substrate 5, and the protective substrate 9 as in the above embodiment is not provided. Since the protective substrate 9 in the above-described embodiment is designed to function as an acoustic matching layer, it is made of a material having an acoustic impedance that matches the piezoelectric film 4 and the subject, and also prevents reflection of the ultrasonic beam. Therefore, it is necessary to set the thickness of the resin layer to 1 / 4λ or a value close thereto. Therefore, in the present embodiment, the second flexible substrate 5 having the ultrasonic wave transmitting member 20 satisfying the above conditions is used so that the function of the protective substrate 9 can be fulfilled.

In the laminated member having the above-mentioned constituent members, the piezoelectric film 4 is fixed near the lead portion 3 of the first flexible substrate 1 as shown in FIG. 4 and the lead portion 2 are fixed so as to cover them. Then, the laminated member is curved in the same manner as in the first embodiment to form the sheath.

The present embodiment constructed as described above is the first
Besides having the same effect as the embodiment, the step of fixing the protective substrate can be omitted. In addition, since the outer diameter of the sheath can be reduced when the sheath is formed by being curved because there is no protective substrate, the outer diameter of the ultrasonic probe can be reduced.

The present invention is not limited to the above embodiment, but various modifications and variations are possible. For example, the present invention may be applied to a so-called convex type ultrasonic probe having no ultrasonic transducer array around the entire circumference of the probe. Further, the lead portion of the flexible substrate may be bent and formed in a substantially right-angled direction, and the present invention may be applied to an ultrasonic probe of an electronic linear or sector method that obtains an ultrasonic tomographic image in the probe insertion direction. Further, when the laminated plate is curved to form the cylindrical sheath, it may be formed by combining laminated members having a semicircular cross section.

[0023]

As described above, according to the present invention, the required constituent members are laminated in a flat plate shape and then curved to form the sheath. Therefore, the ultrasonic probe is easy to manufacture and inexpensive. Can be manufactured. Further, in the bent state, since the positive signal transmission lead portion is located inside the common negative electrode copper foil, the signal line is shielded and less susceptible to external noise. Moreover, since a large space can be formed inside the sheath, a built-in object relating to the endoscope function can be inserted there. When this built-in object is unnecessary, the insertion portion can be configured without considering the arrangement of the built-in object and the diameter of the insertion portion can be reduced, so that the suffering of the subject can be reduced.

[Brief description of drawings]

FIG. 1 is a process explanatory view of a manufacturing method according to a first embodiment of the present invention.

FIG. 2 is an example view of a state in which an endoscope insert is inserted inside the sheath formed according to the first example.

FIG. 3 is a process explanatory view of the manufacturing method according to the second embodiment of the present invention.

FIG. 4 is an exploded perspective view of a laminated member used in a third embodiment of the present invention.

[Explanation of symbols]

 1 1st flexible substrate 2 Lead part 3 Positive electrode part 4 Piezoelectric film 5 2nd flexible substrate 6 Resin 7 Copper foil 8 Conductive layer 9 Protective substrate 10 Misalignment part 11 Sheath 12 Cylindrical hollow

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[Procedure amendment]

[Submission date] March 25, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] 0003

[Correction method] Change

[Correction content]

A similar scanning method is called a mecha-radial method. For example, to explain the configuration applied to an ultrasonic endoscope, a movable part that mechanically rotates the ultrasonic oscillator is installed inside the endoscope tip provided with the ultrasonic oscillator. The ultrasonic beam is formed while rotating the acoustic wave oscillator in the outer peripheral direction of the insertion portion. However, the mecha-radial type has many problems as compared with the electronic radial type. That is, in the electronic radial type, since the ultrasonic transducer is arranged along the outer surface of the endoscope, a cavity can be formed in the central axis portion of the endoscope. A channel for inserting a light guide, a video signal line, forceps or the like can be provided in this cavity.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0004

[Correction method] Change

[Correction content]

Therefore, it becomes possible to obtain an image in the direct viewing direction which enables endoscopic observation, which is extremely advantageous for an endoscope when it is inserted into a body cavity and when it is diagnosed, and medical advantages are great. Further, since the electronic radial type does not have a movable part at the tip of the insertion part, the probability of causing mechanical failure or malfunction is low. The mecha-radial type is inferior in these points, and further requires a transducer protection cover for protecting the movable end portion and an ultrasonic transmission medium for acoustically coupling the ultrasonic transducer and the protective cover.
The transducer protective cover and the ultrasonic transmission medium also cause multiple echoes due to reflection of the ultrasonic beam and sensitivity deterioration due to attenuation.

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] 0006

[Correction method] Change

[Correction content]

For that purpose, it is necessary to provide an ultra-fine multi-core cable in succession to the ultrasonic transducer or to provide a multiplexer for switching and driving several signal lines to each ultrasonic transducer at the probe tip. .. However, due to the nature of the ultrasonic probe in the body cavity, the length of the tip hard part increases,
The above-described configuration that causes the diameter of the endoscope insertion portion to be large is extremely inconvenient. In order to eliminate this inconvenience, an ultrasonic probe is manufactured by applying a precision processing technique, but this has the disadvantage that the product cost increases.

Claims (1)

[Claims] 1. A method of manufacturing an ultrasonic probe in a body cavity having an array of ultrasonic transducers at the tip of an insertion portion, wherein a flexible substrate having at least a plurality of signal transmitting members, a piezoelectric film, and a protective substrate are laminated to form a flat plate. A method for manufacturing an ultrasonic probe in a body cavity, comprising forming a cylindrical sheath by forming a cylindrical laminated member, and then bending the laminated member so that the plurality of signal electric component members are along the outer circumference.