WO2014196783A1

WO2014196783A1 - Apparatus and method for extending field of view of intravascular ultrasound transducers

Info

Publication number: WO2014196783A1
Application number: PCT/KR2014/004930
Authority: WO
Inventors: 정종섭; 김성민; 성진호
Original assignee: 동국대학교 산학협력단
Priority date: 2013-06-07
Filing date: 2014-06-03
Publication date: 2014-12-11
Also published as: KR20140143597A

Abstract

The present invention relates to an apparatus and method for extending the field of view of intravascular ultrasound transducers and, more specifically, to an apparatus for extending the field of view of intravascular ultrasound transducers, the apparatus comprising first and second ultrasound transducers provided on the lateral side and forward side of the end portion of a catheter inserted into a blood vessel so as to obtain in real time and simultaneously a plurality of images from the lateral direction to the forward direction of the catheter, wherein the first ultrasound transducer is provided on one lateral side of the end portion of the catheter, and the second ultrasound transducer is provided in the shape of a curved surface so as to extend from one lateral side to the central part of the forward side of the end portion of the catheter.

Description

Apparatus and method for expanding the viewing angle of intravascular ultrasound transducer

The present invention was made by the task number N01150049 under the support of the Ministry of Knowledge Economy of Korea, the research management specialized organization of the task is "Korea Industrial Technology Development Institute", the research project name is "International Joint Technology Development Project", and the research title is "Diagnosis of cardiovascular lesions" Development high frequency bandwidth [40 ~ 60MHz] high resolution image system and probe technology for diagnosing cardiovascular lesion. " The period is from November 1, 2012 to January 31, 2017.

This patent application claims priority to Korean Patent Application No. 10-2013-0065352 filed with the Korean Patent Office on June 07, 2013, the disclosure of which is hereby incorporated by reference.

The present invention relates to an intravascular ultrasound (IVUS) transducer, and more particularly, using a single device and an array device at the same time, at the same time in the lateral direction from the inside of the blood vessel without the blind spot of the image. The present invention relates to an apparatus and method for expanding the viewing angle of an intravascular ultrasound transducer capable of observing a plurality of images.

In general, the ultrasonic transducer is used for medical and various non-destructive tests, and the higher the sensitivity and the wider the bandwidth, the better the size and resolution of the received signal.

Such an ultrasonic transducer is manufactured using a piezoelectric element. A piezoelectric element is a device having a piezoelectric effect, and when an external force is applied, electric polarization occurs to cause a potential difference, and on the contrary, when a voltage is applied to the piezoelectric element, deformation or deformation force is generated. Say.

On the other hand, cardiovascular disease is a disease that occurs in the heart and major arteries, the major arteries connected to the heart is blocked, bleeding or sagging occurs as a representative disease is atherosclerosis.

Atherosclerosis is a disease in which blood vessels are cured due to blood vessel cholesterol or abnormal proliferation of the lining of the vessel. When atherosclerosis occurs in the coronary artery surrounding the heart, it is called coronary artery disease. appear.

IVUS (Intravascular ultrasound) technology, which uses ultrasound to image the inside of blood vessels, is a technique used to diagnose coronary artery disease. The ultra-small ultrasound transducer penetrates the inside of blood vessels through catheters, which are thin medical tubes. In addition, since the inside of the tube-shaped blood vessel image and the blood pressure information can be displayed in real time while rotating, it is recently used for cardiovascular diagnosis.

1 (a, b, c) is a view showing the shape and image acquisition process of conventional IVUS ultrasound transducers, Figure 1 (a) is a transducer for lateral image acquisition, Figure 1 (b) is a diagonal It is a transducer for directional image acquisition, and FIG. 1 (c) shows a transducer for lateral and omnidirectional image acquisition.

Currently, most IVUS rotates 360 degrees in the axial direction and observes the inner wall (X axis) of the blood vessel perpendicular to the vessel length direction (Z axis) as shown in FIG. 1 (a). In the event that the subjects in the longitudinal direction (Z-axis) and the blood vessels in the diagonal direction have to be observed, these images cannot be acquired in most current commercially available ultrasonic transducer structures.

In order to increase the IVUS ultrasonic transducer viewing angle, the ultrasonic transducer can be placed in the diagonal direction of the distal end of the transducer as shown in FIG. 1 (b), but still the lateral and omnidirectional images cannot be obtained perfectly and the diagonal direction Only one image of is obtained.

In the structure shown in FIG. 1 (c), two transducers can be driven simultaneously to implement lateral and omnidirectional simultaneous images, but the information provided to the clinician is limited because the diagonal images cannot be obtained. do.

In particular, diagonal and omnidirectional images not only provide useful information for diagnosing lesions but also provide IVUS transducers to provide real-time blood flow direction and surrounding blood vessel information in the process of finding the target, making it easier to reach the target. It can also play a role in helping.

The present invention has been created to improve the above-mentioned conventional problems, the vessel can be observed at the same time from the lateral to the forward direction at the same time in the vessel and to eliminate the blind spots of the image generated between the lateral and the forward direction An object of the present invention is to provide an apparatus and method for expanding the viewing angle of an internal ultrasonic transducer.

In addition, the present invention constitutes a single piezoelectric element having a focusing function, and the ultrasonic transducer for observing the lateral direction, and the array piezoelectric element for observing the omnidirectional direction, so that scanning lines can be obtained in the blood vessel direction. It is an object of the present invention to provide an apparatus and method for expanding the viewing angle of an intravascular ultrasound transducer capable of acquiring and providing a high resolution image according to depth from a lateral direction to an anterior direction of a blood vessel.

In order to achieve the object of the present invention as described above, the viewing angle expanding device of the intravascular ultrasound transducer of the present invention is a visual field enlargement apparatus of the intravascular ultrasound transducer, a plurality of lateral direction from the side of the catheter inserted into the blood vessel First and second ultrasonic transducers are installed at side and front ends of the catheter to simultaneously acquire images in real time, the first ultrasonic transducer is installed at one side of the distal end of the catheter, and the second ultrasonic transducer is Characterized in that it is installed in a curved shape so as to extend from the side of the distal end side of the catheter to the center of the front.

The first ultrasonic transducer of the present invention is characterized in that it is installed in a concave shape or a concave / convex lens (lens) for the function of focusing as a single piezoelectric element.

The second ultrasonic transducer of the present invention is an array type piezoelectric element and arranges piezoelectric elements to implement a plurality of scanning lines from the side of the distal end of the catheter to the front to display images having a viewing angle of 90 ° or more between the lateral direction and the omnidirectional direction in the blood vessel. to provide.

In another aspect of the present invention, the apparatus for expanding a viewing angle of an intravascular ultrasound transducer includes: first and second distal end surfaces of the catheter so as to simultaneously acquire a plurality of images from the side direction to the front direction of the catheter inserted into the blood vessel in real time; A second ultrasonic transducer; A catheter driving unit including a motor unit for rotating the catheter 360 ° and a pullback system for moving the catheter in a blood vessel forward and backward direction; A first ultrasonic transducer driver for driving the first ultrasonic transducer; A second ultrasonic transducer driver for driving the second ultrasonic transducer; A screen display unit which outputs a screen of the images transmitted from the first and second ultrasonic transducers; And a controller for controlling the components.

The first ultrasonic transducer of the present invention is installed on one side of the distal end of the catheter, the second ultrasonic transducer is characterized in that it is installed in a curved shape to extend from the one side side of the distal end of the catheter to the center of the front surface.

The first ultrasonic transducer of the present invention is characterized in that it is installed in a concave shape for the function of focusing as a single piezoelectric element, or further provided with a concave / convex lens.

The first ultrasonic transducer driving unit of the present invention and the first signal generator for generating a transmission signal for operating the first ultrasonic transducer installed in the distal end of the catheter in accordance with the control signal of the control unit; A first transmission amplifier for amplifying the transmission signal and transmitting the amplified signal to the first ultrasonic transducer; A first receiving amplifier for amplifying a received signal transmitted from the first ultrasonic transducer; And a first signal processor converting the received signal into an image signal and transferring the received signal to the screen display unit.

The second ultrasonic transducer driver of the present invention includes a second signal generator for generating a transmission signal for operating the second ultrasonic transducer installed in the distal end of the catheter in accordance with the control signal of the controller; A transmission focusing unit for outputting a transmission signal of which the irradiation time is adjusted by adjusting the irradiation time so that the ultrasonic wave irradiated through the second ultrasonic transducer is irradiated to one focal point of the object when the transmission signal is transmitted; A second transmission amplifier for amplifying the transmission signal and transmitting the amplified signal to the second ultrasonic transducer; A second receiving amplifier for amplifying the received signal from the second ultrasonic transducer; A reception focusing unit configured to correct a difference in the respective ultrasound arrival times reflected by the object to the second ultrasound transducer when the received signals are delivered to match phases between the received signals reflected from a focal point; And a second signal processor converting the received signal into an image signal and transferring the received signal to the screen display unit.

In another aspect of the present invention, a method for expanding a viewing angle of an intravascular ultrasound transducer includes: a) a first side of the catheter in front of the distal side and the anterior direction of the catheter inserted into the vessel; Generating and amplifying an electrical transmission signal corresponding to the frequency and intensity of the ultrasonic waves to be irradiated from the first and second ultrasonic transducers according to the control signal with the second ultrasonic transducer installed; b) converting the amplified transmission signal into an ultrasonic wave and radiating the amplified transmission signal into an ultrasonic wave to irradiate the object and receiving the ultrasonic wave reflected from the object; And c) amplifying the received signal, converting the received signal into an image signal, and displaying the same through the screen display unit.

According to the present invention, when the electrical transmission signal corresponding to the frequency and intensity of the ultrasonic wave to be irradiated through the second ultrasonic transducer is generated in step a), the second ultrasonic transducer 54 is irradiated through the transmission focusing unit. And amplifying a transmission signal of which the irradiation time is adjusted by adjusting the irradiation time so that ultrasonic waves may be irradiated to one focal point of the object.

The present invention amplifies a received signal converted into an electrical received signal through the second ultrasonic transducer in step b) and each ultrasonic wave arrival time reflected from the object to the second ultrasonic transducer through the receiving focusing unit. Compensating the difference between the phases of the received signal reflected from the focusing point is further characterized in that it comprises a step.

As described above, according to the present invention, by placing the ultrasonic transducers over the distal side and the front of the catheter and having a convex spherical shape, the distal end of the catheter can simultaneously provide images from the lateral direction to the front direction, as well as the lateral and There is an advantage that can remove the blind spots of the image generated between all directions.

In addition, the present invention is the ultrasonic transducer disposed in the distal direction of the catheter is composed of a single piezoelectric element, it can be made to be concave spherical or to implement a focusing function using a lens to increase the sensitivity and resolution of the lateral image In addition, the ultrasonic transducer for observing the omnidirectional is arranged in the direction of the blood vessel as an array type piezoelectric element has the advantage of providing an image according to the depth from the diagonal direction to the omnidirectional direction.

1 (a), (b), (c) is a view showing the shape and image acquisition process of conventional IVUS ultrasound transducers.

Figure 2 is a block diagram showing the configuration of the viewing angle expansion device of the intravascular ultrasound transducer according to the present invention.

3 (a) and 3 (b) are exemplary views illustrating a structure and an image acquisition process of an ultrasonic transducer according to the present invention.

4 is a flowchart illustrating a method of expanding a viewing angle of an intravascular ultrasound transducer according to the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Figure 2 is a block diagram showing the configuration of a system for driving the ultrasonic transducer according to the present invention, Figure 3 (a), (b) is an exemplary view showing the structure and image acquisition process of the ultrasonic transducer according to the present invention. .

As shown in FIG. 2 and FIG. 3, the apparatus for expanding the viewing angle of the intravascular ultrasound transducer according to the present invention includes a first ultrasound transducer driver 10, a second ultrasound transducer driver 20, and a catheter driver 30. , A catheter 50, a screen display 60, and a controller 70.

The first ultrasonic transducer driver 10 includes a first signal generator 12, a first transmit amplifier 14, a first receive amplifier 16, and a first signal processor 18. The signal generator 12 generates a transmission signal for operating the first ultrasonic transducer 52 which is a single piezoelectric element installed on the side of the catheter 50 according to the control signal of the controller 70. The transmission amplifier 14 receives and amplifies the transmission signal generated by the first signal generator 12. Here, the first transmission amplifier 14 may further include a band pass filter.

The first transmit amplifier 14 transmits the amplified transmit signal to the first ultrasound transducer 52, and the first ultrasound transducer 52 is transmitted from the first transmit amplifier 14. The transmission signal is converted into ultrasonic waves and irradiated to the object.

The first ultrasonic transducer 52 receives the ultrasonic waves reflected from the object and converts the ultrasonic waves into a received signal, and the first receiving amplifier 16 amplifies the received signal transmitted from the first ultrasonic transducer 52. To the first signal processor 18.

The first signal processor 18 receives the received signal amplified from the first receiving amplifier 16 according to the control signal of the controller 17, converts the received signal into an image signal, and transmits the received signal to the screen display unit 60. The screen display unit 60 receives the converted video signal from the first signal processor 18 and displays the screen. The screen display unit 800 may be, for example, a CRT monitor, an LCD monitor, an LED monitor, or the like.

The second ultrasonic transducer driver 20 includes a second signal generator 21, a transmission focusing unit 22, a second transmission amplifier 23, a second reception amplifier 26, a reception focusing unit 27, And a second signal processing unit 28, wherein the second signal generator 21 is a second ultrasonic transducer which is an array type piezoelectric element installed on the front surface of the catheter 50 according to the control signal of the controller 70. A transmission signal for operating 54 is generated and transmitted to the transmission focusing unit 22.

When the transmission signal generated by the second signal generator 21 is transmitted, the transmission focusing unit 22 may irradiate one focal point of the object with ultrasonic waves irradiated through the second ultrasonic transducer 54. The irradiation time is adjusted by adjusting the irradiation time differently so that the irradiation time is adjusted, and the second transmission amplifier 24 receives and amplifies the transmission signal output from the transmission focusing unit 22. Here, the second transmission amplifier 23 may further include a band pass filter.

The second transmission amplifier 23 transmits the amplified transmission signal to the second ultrasonic transducer 54, and the second ultrasonic transducer 54 is transferred from the second transmission amplifier 23. The transmission signal is converted into ultrasonic waves and irradiated to the object.

The second ultrasonic transducer 54 receives the ultrasonic waves reflected from the object and converts the ultrasonic waves into a received signal, transfers the converted received signal to the second receiving amplifier 26, and transmits the second received amplifier ( 26 amplifies the received signal transmitted from the second ultrasonic transducer 54 and transmits the received signal to the receiving focusing unit 27.

The reception focusing unit 27 receives the received signals amplified from the second reception amplifier 26 and corrects the difference between the respective ultrasound arrival times reflected from the object to the second ultrasound transducer 54. The phases of the received signals reflected from the focal point are matched.

The second signal processor 28 receives the received signal transmitted from the receiving focusing unit 27 according to the control signal of the controller 70, converts the received signal into an image signal, and transmits the converted signal to the screen display unit 60. The screen display unit 60 receives the converted video signal from the second signal processor 28 and displays the screen.

Here, the transmission focusing unit 22 and the reception focusing unit 27 are used in an environment in which the second ultrasonic transducers 54 are arranged in an array form, and the elements of the second ultrasonic transducers 54 Since the time for irradiating ultrasonic waves to the object and the time for reflecting back from the object to the elements of the second ultrasonic transducer 54 are different, the time difference is corrected.

The catheter drive unit 30 includes a motor unit 32 and a pull back system 34, and the motor unit 32 rotates the catheter 50 by 360 ° according to a control signal of the control unit 70. In addition, the pullback system 34 moves the catheter 50 back and forth according to the control signal of the controller 70.

As shown in (a) and (b) of FIG. 3, the catheter 50 is rotated 360 ° by the motor unit 32, and simultaneously acquires a plurality of images from side to front in real time. The first and second ultrasonic transducers 52 and 54 are installed to remove the blind spot between the lateral direction and the omnidirectional direction.

The first ultrasonic transducer 52 is installed on one side of the catheter 50 as shown in (a) of FIG. 3 and is installed in a concave aperture shape or a concave / convex lens for the function of focusing. The second ultrasonic transducer 54 is installed in a curved shape so as to extend from one side surface of the catheter 50 to a central portion of the front surface as shown in FIG.

Accordingly, the first ultrasound transducer 52 rotates the catheter 50 inserted into the blood vessel by 360 ° so that the second ultrasound transducer 54 having the curved side shape of the lateral image inside the blood vessel is a blood vessel. A plurality of images from the inner side to the omnidirectional direction may be obtained.

As shown in (a) of FIG. 3, the viewing angle of the present invention is 90 °, and since the array type piezoelectric elements are used as shown in (b) of FIG. 2, a plurality of scanning lines can be configured from the side to the front. As such, it is possible to provide images having a wide viewing angle without an image blind spot between the omnidirectional and lateral directions of the conventional IVUS converter shown in FIG.

Meanwhile, when the first ultrasonic transducer 52 has a planar shape, since the sensitivity and the resolution are reduced, the lens attaching method may be used in addition to the focusing method using the pressed technique. The second ultrasonic transducer 54 may provide a function of acquiring a plurality of scan lines and transmitting / receiving dynamic focusing according to depths through time delays of the array piezoelectric elements.

Referring to FIG. 4, the method for expanding the viewing angle of an intravascular ultrasound transducer according to the present invention may include a catheter 50 so as to simultaneously acquire a plurality of images in real time from the lateral direction to the omnidirectional direction of the catheter 50 inserted into the blood vessel. The first and second ultrasonic transducers 52 and 54 are installed on the side and front surfaces of the distal end portions.

The controller 70 controls the first signal generator 12 to generate an electrical transmission signal corresponding to the frequency and intensity of the ultrasonic wave to be irradiated through the first ultrasonic transducer 52 (S10). The transmission signal is amplified using the first transmission amplifier 14 (S20), and the first ultrasound transducer 12 converts the transmission signal amplified from the first transmission unit 14 into ultrasound and irradiates the object. (S30).

The first ultrasonic transducer 52 receives the ultrasonic waves reflected from the object and converts the ultrasonic waves into electrical reception signals (S40), amplifies the received signals through the first reception amplifier 16 (S50), and the controller. 70 controls the first signal processor 18 to convert the amplified received signal into an image signal (S60), and displays the image signal on the screen through the screen display unit 60 (S70).

In addition, the controller 70 controls the catheter drive unit 30 to rotate the catheter 50 through the motor unit 32, 360 degrees through the pullback system 34 in the blood vessel back and forth direction Move it.

The control unit 70 controls the second signal generator 21 to generate an electrical transmission signal corresponding to the frequency and intensity of the ultrasonic wave to be irradiated through the second ultrasonic transducer 54, and the transmission focusing unit When the transmission signal is transmitted, the irradiation time is adjusted by adjusting the irradiation time differently so that the ultrasonic wave irradiated through the second ultrasonic transducer 54 may be irradiated to one focal point of the object, and thus the transmission signal is adjusted. The second transmission amplifier 24 receives and amplifies the transmission signal output from the transmission focusing unit 22.

The second transmission amplifier 23 transmits the amplified transmission signal to the second ultrasonic transducer 54, and the second ultrasonic transducer 54 is transferred from the second transmission amplifier 23. The transmission signal is converted into ultrasonic waves and irradiated to the object, and at the same time, the ultrasonic wave reflected from the object is received and converted into a reception signal, and the converted reception signal is transmitted to the second reception amplifier 26.

The second receiving amplifier 26 amplifies the received signal transmitted from the second ultrasonic transducer 54 and transmits the received signal to the receiving focusing unit 27, and the receiving focusing unit 27 transmits the received receiving signal. The phases of the received signals reflected from the focal point are matched by correcting the difference in the respective ultrasound arrival times reflected from the object to the second ultrasound transducer 54.

According to the present invention configured as described above, the ultrasonic transducers are disposed over the distal side and the front of the catheter, and the distal end has a convex spherical shape to simultaneously provide images from the lateral to the omnidirectional as well as the lateral and the omnidirectional. There is an advantage that can remove the blind spot of the image occurring in between.

Or more, the above-described embodiment of the present invention, which is disclosed for the purpose of illustration, those skilled in the art, within the technical spirit and the technical scope of the present invention disclosed in the appended claims below, another various embodiments Improvements, changes, substitutions or additions will be possible.

Claims

In the viewing angle expanding device of the intravascular ultrasound transducer,

First and second ultrasound transducers are installed on the side and front of the distal end of the catheter to simultaneously acquire a plurality of images from the side to the front direction of the catheter inserted into the blood vessel in real time.

The first ultrasonic transducer is installed on one side of the distal end of the catheter,

The second ultrasonic transducer is a viewing angle expanding device of the intravascular ultrasound transducer, characterized in that it is installed in a curved shape so as to extend from the side of one side of the distal end of the catheter to the center of the front.
The method of claim 1,

The first ultrasonic transducer is installed in a concave shape for the function of focusing as a single piezoelectric element, or a convex / convex lens is further installed, the viewing angle expansion device of the intravascular ultrasound transducer.
The method according to claim 1 or 2,

The second ultrasonic transducer is an array type piezoelectric element that arranges piezoelectric elements to implement a plurality of scanning lines from the distal end side of the catheter to the front to provide images having a viewing angle of 90 ° or more between the lateral and anterior directions in the vessel. Viewing angle magnifier of my ultrasonic transducer.
First and second ultrasonic transducers installed at the side and front end portions of the catheter to simultaneously acquire a plurality of images from the side direction to the front direction of the catheter inserted into the blood vessel in real time;

A catheter driving unit including a motor unit for rotating the catheter 360 ° and a pullback system for moving the catheter in a blood vessel forward and backward direction;

A first ultrasonic transducer driver for driving the first ultrasonic transducer;

A second ultrasonic transducer driver for driving the second ultrasonic transducer;

A screen display unit which outputs a screen of the images transmitted from the first and second ultrasonic transducers; And

And a control unit for controlling the components.
The method of claim 4, wherein

The first ultrasonic transducer is installed on one side of the distal end of the catheter,

The second ultrasonic transducer is a viewing angle expanding device of the intravascular ultrasound transducer, characterized in that it is installed in a curved shape so as to extend from the side of one side of the distal end of the catheter to the center of the front.
The method according to claim 4 or 5,

The first ultrasonic transducer is

A concave shape or a convex / convex lens is further provided for concentrating as a single piezoelectric element.
The method according to claim 4 or 5,

The second ultrasonic transducer is

An array of piezoelectric elements, in which the piezoelectric elements are arranged to realize a plurality of scanning lines from the side of the distal end of the catheter to the front, to enlarge the viewing angle of the intravascular ultrasound transducer that provides images having a viewing angle of 90 ° or more between the lateral and anterior directions of the vessel. Device.
The method according to claim 4 or 5,

The first ultrasonic transducer driver

A first signal generator for generating a transmission signal for operating the first ultrasonic transducer installed at the distal end of the catheter according to a control signal of the controller;

A first transmission amplifier for amplifying the transmission signal and transmitting the amplified signal to the first ultrasonic transducer;

A first receiving amplifier for amplifying a received signal transmitted from the first ultrasonic transducer; And

And a first signal processor configured to convert the received signal into an image signal and transmit the received signal to the screen display unit.
The method according to claim 4 or 5,

The second ultrasonic transducer driver

A second signal generator for generating a transmission signal for operating a second ultrasonic transducer installed at the distal end of the catheter according to a control signal of the controller;

A transmission focusing unit for outputting a transmission signal of which the irradiation time is adjusted by adjusting the irradiation time so that the ultrasonic wave irradiated through the second ultrasonic transducer is irradiated to one focal point of the object when the transmission signal is transmitted;

A second transmission amplifier for amplifying the transmission signal and transmitting the amplified signal to the second ultrasonic transducer;

A second receiving amplifier for amplifying the received signal from the second ultrasonic transducer;

A reception focusing unit configured to correct a difference in the respective ultrasound arrival times reflected by the object to the second ultrasound transducer when the received signals are delivered to match phases between the received signals reflected from a focal point; And

And a second signal processor for converting the received signal into an image signal and transferring the received signal to the screen display unit.
a) the first and second ultrasonic transducers are installed on the side and front of the distal end of the catheter to simultaneously acquire a plurality of images from the lateral direction to the forward direction of the catheter inserted into the blood vessel according to the control signal; Generating and amplifying an electrical transmission signal corresponding to the frequency and intensity of the ultrasonic wave to be irradiated by the second ultrasonic transducer;

b) converting the amplified transmission signal into an ultrasonic wave and radiating the amplified transmission signal into an ultrasonic wave to irradiate the object and receiving the ultrasonic wave reflected from the object; And

c) amplifying the received signal, converting the received signal into an image signal, and displaying the image signal through a screen display unit;
The method of claim 10,

When the electrical transmission signal corresponding to the frequency and intensity of the ultrasonic wave to be irradiated through the second ultrasonic transducer in step a) is generated, focusing the ultrasonic wave irradiated through the second ultrasonic transducer through the transmission focusing unit And amplifying a transmission signal of which the irradiation time is adjusted by adjusting the irradiation time so as to be irradiated to the point.
The method of claim 11,

Amplifying the received signal converted into an electrical reception signal through the second ultrasonic transducer in step b) and the difference of the respective ultrasonic wave arrival time reflected from the object to the second ultrasonic transducer through the receiving focusing unit And correcting the phases of the received signals reflected from the focal points so that the phases coincide with each other.
The method according to claim 10 or 12,

The first ultrasonic transducer is installed on one side of the distal end of the catheter, the second ultrasonic transducer is installed in a curved shape so as to extend from one side of the distal end of the catheter to the center of the front surface, the viewing angle of the intravascular ultrasound transducer How to enlarge.
The method of claim 13,

The first ultrasonic transducer is provided in a concave shape for the function of focusing as a single piezoelectric element, or a concave / convex lens is further installed, characterized in that the viewing angle of the intravascular ultrasound transducer.
The method of claim 13,

The second ultrasonic transducer is an array type piezoelectric element that arranges piezoelectric elements to implement a plurality of scanning lines from the distal end side of the catheter to the front to provide images having a viewing angle of 90 ° or more between the lateral and anterior directions in the vessel. How to enlarge the viewing angle of my ultrasound transducer.