JP6990794B1 - Array type ultrasonic imaging device and its control method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an array-type ultrasonic imaging device having less image deviation and a control method thereof in an array-type ultrasonic imaging device for generating a wide-range reflected wave image of a subject by reciprocating scanning an array-type ultrasonic probe. SOLUTION: An ultrasonic beam is irradiated on a surface or a laminated boundary surface of a subject 8 by scanning an ultrasonic array probe 4 in which a plurality of transducers of the present invention are linearly arranged in a plane, and the ultrasonic reflected wave is generated. The array-type ultrasonic imaging device 1 that displays the signal strength performs an electronic scan in which the ultrasonic array probe irradiates an ultrasonic beam in a predetermined scanning order, and also performs an ultrasonic array in a direction perpendicular to the juxtaposed direction of the transducers. By scanning the ultrasonic array probe in a plane by a scanning operation that moves the probe back and forth and a shifting operation that moves the ultrasonic array probe parallel to the juxtaposed direction of the transducer, the ultrasonic beam is irradiated in a predetermined scanning order. , The deviation of the display of the ultrasonic reflected wave at the position where the outward path and the return path of the scanning operation are switched is corrected. [Selection diagram] FIG. 6B

Description

The present invention relates to an array type ultrasonic imaging device and a control method thereof.

There is an ultrasonic imaging device that irradiates a subject such as a semiconductor with ultrasonic waves, generates image information inside the subject based on the reflected wave, and detects defects inside the subject. According to this ultrasonic imaging device, non-destructive high-resolution inspection can be performed, and the reliability of electronic components can be ensured.

One form of an ultrasonic imaging device is an ultrasonic imaging device having a single probe composed of a single oscillator. In the ultrasonic imaging device having this single probe, the single probe is mechanically scanned in the X and Y directions of the predetermined area of the surface of the subject or the laminated interface, and the ultrasonic irradiation to the subject and the reflected wave are generated. Perform detection.

In order to shorten the tact time of this ultrasonic imaging device, it is necessary to increase the scanning speed of the single probe. However, in an ultrasonic imaging device in which a subject and a single probe are flooded, if the scanning speed of the single probe is increased, there arises a problem that a phenomenon that causes image deterioration such as bubble entrainment and waviness occurs.

Therefore, for example, an array-type ultrasonic sensor having a plurality of piezoelectric vibration elements is provided, and the inside of the inspection target is internally scanned by electronically scanning in the array alignment direction and mechanical scanning in the array alignment normal direction. There is an ultrasonic inspection device that generates an inspection image using a reflected signal from (see Patent Document 1).

Japanese Unexamined Patent Publication No. 2007-263780

According to the above-mentioned prior art, since the scanning speed of the probe can be reduced, it is possible to reduce the occurrence of phenomena that cause image deterioration such as bubble entrainment and waviness. However, when the array-type ultrasonic probe is reciprocally scanned by a reciprocating machine to generate a wide-range reflected wave image of the subject, the ultrasonic probe is super-scanned at the end of the machine scan, that is, at the position where the outward path and the return path of the mechanical scan are switched. The image of the reflected sound wave may be misaligned. Patent Document 1 does not describe the reciprocating mechanical scanning of an array-type ultrasonic probe, and does not consider this problem.

An object of the present invention is to provide an array-type ultrasonic imaging device having less image deviation and a control method thereof in an array-type ultrasonic imaging device that reciprocally scans an array-type ultrasonic probe to generate a reflected wave image of a subject. There is something in it.

In order to solve the above problems, the array-type ultrasonic imaging device of the present invention uses an ultrasonic array probe in which a plurality of transducers are linearly arranged side by side to irradiate a subject with an ultrasonic beam in a predetermined scanning order. While scanning, a plane scan is performed by a scan operation of reciprocating in a direction perpendicular to the juxtaposed direction of the transducer and a shift operation of moving the ultrasonic array probe in parallel with the juxtaposed direction of the transducer. An array-type ultrasonic imaging device that irradiates the surface of a sample or the boundary surface of a stack with an ultrasonic beam and displays the signal intensity of the ultrasonic reflected wave from the subject . The electronic scan is irradiated at one end of the electronic scan. The points are irradiated with the ultrasonic beam, and then the ultrasonic beams are alternately irradiated from each end toward the central part so as to irradiate the opposite irradiation points at the other ends. The plurality of transducers are selected so as to be in the scanning order and irradiated with an ultrasonic beam .

Further, in the control method of the array type ultrasonic imaging device of the present invention, the subject is sequentially irradiated with the ultrasonic beam of an ultrasonic array probe in which a plurality of transducers are linearly arranged side by side to perform an electronic scan, and the subject is subjected to an electronic scan. This is a control method for an array-type ultrasonic imaging device that displays the signal intensity of ultrasonic reflected waves from a sample. The subject is irradiated with an ultrasonic beam at one end of an electronic scan in a predetermined scanning order. Next, the plurality of ultrasonic beams are radiated alternately from each end toward the central part so as to irradiate the ultrasonic beam to the irradiation points at the other ends facing each other. The first step of continuously moving the ultrasonic array probe at a predetermined speed in a direction perpendicular to the juxtaposed direction of the transducers of the ultrasonic array probe while selecting an ultrasonic beam and irradiating the ultrasonic beam, and the above-mentioned A shift step that moves the ultrasonic array probe in parallel with the juxtaposed direction of the transducer by the scanning width of the electronic scan, and an irradiation point at one end of the electronic scan in a predetermined scanning order for the subject. Scanning sequence in which the ultrasonic beam is irradiated alternately from each end toward the central part so as to irradiate the ultrasonic beam to the irradiation points at the other ends facing each other. The second step of continuously moving the ultrasonic array probe at a predetermined speed in the direction opposite to the first step while irradiating the ultrasonic beam by selecting the plurality of transducers so as to be. By repeating the first step, the shift step, and the second step, the entire surface of the subject was electronically scanned .

According to the present invention, in an array-type ultrasonic imaging device that scans an array-type ultrasonic probe in a plane to generate an ultrasonic reflection image of a subject, the reflected wave image generated in the reciprocating motion of the scan of the array-type ultrasonic probe. Image misalignment can be suppressed.

It is a figure which shows the whole structure of the array type ultrasonic imaging apparatus of embodiment. It is a figure explaining the operation content of the plane scanning of a probe in an array type ultrasonic imaging apparatus. It is a figure explaining the irradiation point of the ultrasonic beam of the probe of the comparative example. It is a figure which shows the position of the irradiation point of the ultrasonic beam in the plane scan of the probe of the comparative example. It is a figure which shows an example of the time change of a signal intensity in a reflected wave. It is a figure explaining that the signal intensity of a reflected wave is converted into the gradation degree of 0 to 255. It is a figure which shows the positional relationship of the subject 8 which has three regions with different reflectances in a strip shape with an irradiation point of an ultrasonic beam. It is a figure which shows the ultrasonic image by the electronic scan in FIG. 4C. It is a figure which shows the position of the irradiation point of an electron scan when the outer shape of a subject is made into a scanning area by the probe 4 of the comparative example. It is a figure which shows the ultrasonic image by the electronic scan of FIG. 5A. It is a figure explaining the irradiation point of the ultrasonic beam of the probe 4 of an embodiment. It is a figure which shows the position of the irradiation point of the ultrasonic beam in the plane scan of a probe. It is a figure which shows the position of the irradiation point of an electron scan when the outer shape of the subject in an embodiment is a scanning area. It is a figure which shows the ultrasonic image by the electronic scan of FIG. 7A. It is a flow diagram explaining the operation of the plane scanning of the array type ultrasonic imaging apparatus. It is a flow chart which shows the details of the process of an electronic scan.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a diagram showing an overall configuration of an array-type ultrasonic imaging device according to an embodiment.

The array-type ultrasonic imaging device 1 includes a 3-axis scanner 2 (scanning means) and an ultrasonic array probe (hereinafter referred to as probe 4). The 3-axis scanner 2 scans the probe 4 with respect to the planar subject 8 in two dimensions in the X-axis direction and the Y-axis direction (planar scanning). As a result, the array-type ultrasonic imaging device 1 can visualize the planar subject 8 by ultrasonic waves.

The probe 4 is a phased array ultrasonic probe in which a large number of oscillators are arranged in a strip shape. Specifically, an ultrasonic convergent beam (ultrasonic beam) is created by controlling the oscillation timing of some of a plurality of oscillators (oscillator group) in a large number of oscillators, and this is electronically switched. Then, the irradiation position is changed, the ultrasonic beam is irradiated, and the subject 8 is scanned one-dimensionally. In the present specification, the scanning of an electronic ultrasonic beam by a phased array ultrasonic probe is referred to as an electronic scan.
The reception control of the reflected wave of the ultrasonic beam is also performed by controlling the oscillator group.

Further, the probe 4 may focus the ultrasonic waves generated from a single oscillator with an acoustic lens and irradiate the subject with a plurality of these oscillators in a strip shape. Even in this configuration, by electronically switching the oscillator, the irradiation position of the ultrasonic beam is changed, and the subject 8 is electronically scanned.

The probe 4 is immersed in water filled in the water tank 91, and the tip of the probe 4 is arranged so as to face the subject 8. The probe 4 is attached to the 3-axis scanner 2 by the holder 24.
The water tank 91 is placed on the table 92.

When scanning the probe 4 in two dimensions, the 3-axis scanner 2 detects the scanning position based on the linear position or the rotational position (angle position) detected by the built-in position change-detecting encoder. As a result, the array-type ultrasonic imaging device 1 can visualize the relationship between each scanning position (scanning point) of the subject 8 and the echo wave in two dimensions.

The 3-axis scanner 2 includes an X-axis scanner 21 and a Y-axis scanner 22 that scan the probe 4, a Z-axis scanner 23 that changes the distance between the probe 4 and the subject 8, and a holder 24 that holds the probe 4. ..
Further, the height of the probe 4 is adjusted by the table 92 before the inspection, and the distance between the probe 4 and the subject 8 is adjusted by the Z-axis scanner 23.

The probe 4 continuously moves at a predetermined speed by the X-axis scanner 21 of the 3-axis scanner 2 in a direction perpendicular to the direction in which a plurality of transducers are linearly arranged side by side (hereinafter, this direction is referred to as an X-axis direction). After that, the Y-axis scanner 22 of the 3-axis scanner 2 moves (shifts) by the scanning width of the electronic scan in parallel with the parallel direction of the plurality of transducers.

The holder 24 supports a flange portion 42 provided on the upper part of the probe 4 so that the holder 24 moves smoothly upward when an upward force is applied to the probe 4. A sensor 3 is provided on the holder 24 to detect that the probe 4 has moved upward.

The control device 10 includes a control unit 18, a transmission / reception command unit 12, a timing processing unit 13, an oscillator operation signal generation unit 14, a reflected wave signal processing unit 15, a reflected wave image generation unit 16 and a display unit 17, and is a 3-axis scanner. Control, transmission / reception control of the probe 4, and display control of the echo wave from the subject 8.

The mechanical control unit 11 drives the X-axis scanner 21 and the Y-axis scanner 22 based on the encoder output built in the X-axis scanner 21 and the Y-axis scanner 22, and the probe 4 scans the subject 8 in a plane. Is.

The transmission / reception command unit 12 is a control unit that commands the oscillator operation signal generation unit 14 to generate an oscillator operation signal via the timing processing unit 13 and starts electronic scanning of the probe 4.

The timing processing unit 13 selects a group of oscillators of the probe 4 corresponding to the scanning order of the ultrasonic beam in the electronic scan.

The oscillator operation signal generation unit 14 generates an oscillator operation signal according to the oscillator group selected by the timing processing unit 13 and the scanning order, and transmits the oscillator operation signal to the probe 4 at each scanning point.
The probe 4 irradiates an ultrasonic beam with the oscillator operation signal of the oscillator operation signal generation unit 14.

The reflected wave signal processing unit 15 receives the reflected wave signal of the ultrasonic beam from the probe 4 at each scanning point, provides a gate and performs gate processing to obtain the displacement (amplitude) of the reflected wave, and the displacement is used. Calculate the signal strength.

The reflected wave image generation unit 16 converts the signal intensity of the reflected wave for each irradiation point calculated by the reflected wave signal processing unit 15 into, for example, a gradation degree of 0 to 255. Reflected waves of the ultrasonic beam are generated at the boundary surface between the subject 8 and the water in the water tank 91 and the boundary surface where the acoustic impedance (density) changes, such as the material boundary, the peeled portion, and the void portion inside the subject 8. The reflected wave image generation unit 16 reduces the gradation degree at points where there is no reflected wave of the ultrasonic beam as the gradation degree increases and the signal intensity of the reflected wave increases.

The display unit 17 displays the signal intensity of the reflected wave of the ultrasonic beam obtained by the reflected wave image generation unit 16 as a grayscale image scanned in a plane of the subject 8. Specifically, when the gradation degree is 255, black is displayed, when the gradation degree is 0, white is displayed, and when the gradation degree is an intermediate value, gray is displayed according to the gradation degree.
As a result, the array-type ultrasonic imaging device 1 displays the cavity of the subject 8 scanned in a plane (the difference in density from the surroundings is large) as a white image.

The control unit 18 controls the mechanical control unit 11 and controls the transmission / reception command unit 12 in synchronization with the encoder output of the X-axis scanner 21 notified from the mechanical control unit 11. That is, the control unit 18 starts electronic scanning in synchronization with the scanning operation of the probe 4. As a result, the scanning pitch of the subject 8 in the X-axis direction by the electronic scanning of the probe 4 becomes equal to the pitch of the encoder output of the X-axis scanner 21.

Next, with reference to FIG. 2, the operation contents of the plane scanning of the probe 4 in the array type ultrasonic imaging apparatus 1 will be described.
The probe 4 is configured by, for example, 192 oscillators arranged side by side in a linear manner. In FIG. 2, the probe 4 has seven oscillators a, b, c, d, e, f, and g. The case where it is composed of the oscillator of is shown.

The array-type ultrasonic imaging device 1 sets the set position of the subject 8 as the origin of scanning (upper left of the scanning area in FIG. 2), specifies the size of the scanning area, and performs planar scanning of the probe 4.
First, the 3-axis scanner 2 is driven to move the probe 4 so that the start point of the electronic scan of the probe 4 is located at the origin of the scan. Specifically, since the electron scan is performed while the probe 4 is moving, the probe 4 moves including the run-up portion so that the movement speed when the probe 4 passes the start point of the electron scan becomes a predetermined value.

At the origin (start position) of the plane scan, the probe 4 performs an electronic scan by the oscillators a, b, c, d, e, f, and g, and the X-axis scanner 21 of the 3-axis scanner 2 performs an electronic scan of the oscillator. Move in the direction perpendicular to the juxtaposition direction. Then, the probe 4 performs the next electronic scan in synchronization with the encoder output of the X-axis scanner 21. The probe 4 repeats this for the width of the scanning area (the size in the X-axis direction).

As described above, the probe 4 repeats the electronic scan while continuously moving the probe 4 in the X-axis direction (scanning operation 1), and the length in the Y-axis direction is the scanning width of the electronic scan. The ultrasonic beam is irradiated to the strip-shaped scanning area corresponding to the width of the scanning area in which the length in the axial direction is set, and the reflected wave from the subject 8 is detected.

At this time, the control device 10 uses the reflected wave from the subject 8 detected by one electronic scan of the probe 4 as the reflected wave of the ultrasonic beam having the same position (scanning row) in the X-axis direction. The signal strength of is calculated and displayed as a shading image.

Next, the probe 4 is moved (shifted) by the scanning width of the electronic scan in parallel with the juxtaposed direction of the plurality of oscillators by the Y-axis scanner 22 of the 3-axis scanner 2. Then, the probe 4 is moved by the X-axis scanner 21 so that the start point of the electron scan of the probe 4 is at the same position in the X-axis direction as the start point of the last electron scan of the scan operation 1 described above.

The probe 4 performs electronic scanning by the oscillators a, b, c, d, e, f, and g, and the X-axis scanner 21 of the 3-axis scanner 2 arranges oscillators in the direction opposite to the scanning operation 1 in parallel. Move in the direction perpendicular to the direction. Then, the probe 4 performs the next electronic scan in synchronization with the encoder output of the X-axis scanner 21. The probe 4 repeats this for the width of the scanning area (the size in the X-axis direction).

As described above, the probe 4 repeats the electronic scan while continuously moving the probe 4 in the X-axis direction (scanning operation 2), and the length in the Y-axis direction is the scanning width of the electronic scan. The ultrasonic beam is irradiated to the strip-shaped scanning area corresponding to the width of the scanning area in which the length in the axial direction is set, and the reflected wave from the subject 8 is detected.

If the control device 10 can cover the designated scanning area by the scanning operation 1 and the scanning operation 2 of the probe 4, the control device 10 ends the plane scanning, but if the probe 4 is insufficient, the probe 4 is divided by the scanning width of the electronic scan. The shift operation is performed to move, and the same electronic scan as the previous operation, as well as the scan operation 3, the shift operation, and the scan operation 4 are performed.
The control device 10 repeats the above operation until it covers the designated scanning area, and scans the subject 8 in a plane.

In the present specification, the scan operation 1, the scan operation 3 ... Of the probe 4 are referred to as a forward scan operation (first scan operation), and the scan operation 2, the scan operation 4 ... Of the probe 4 are referred to as a reverse scan operation (second scan operation). Scan operation).

Since the probe 4 performs electron scanning while continuously moving in the above scanning operations 1, 2, 3, and 4, more specifically, the X-axis direction of the irradiation point of the ultrasonic beam is determined by the irradiation timing of the ultrasonic beam. There is a shift in the position of. Next, the relationship between the irradiation timing of the ultrasonic beam and the irradiation point will be described.

FIG. 3A is a diagram illustrating an irradiation point of the ultrasonic beam of the probe 4 of the comparative example.
The irradiation points a, b, c, d, e, f, and g are irradiation points of the ultrasonic beam by electron scanning of the oscillators a, b, c, d, e, f, and g of the probe 4. In particular, the irradiation point a is an irradiation point corresponding to the origin of the scanning area, and is an irradiation point of the first ultrasonic beam of the electronic scan synchronized with the encoder output of the X-axis scanner 21 during the scanning operation.

The electronic scan of the probe 4 is performed during the continuous movement of the scan operation. The solid rectangle in FIG. 3A indicates the position of the probe 4 when the ultrasonic beam is first irradiated, and the broken line rectangle indicates the position of the probe 4 when the ultrasonic beam is finally irradiated.
In the probe 4 of the comparative example, the ultrasonic beam is sequentially irradiated from the irradiation point a toward the other end of the probe 4. Therefore, the irradiation points b, c, d, e, f, and g are slightly displaced in the scanning direction.

FIG. 3B is a diagram showing the positions of the irradiation points of the ultrasonic beam in the plane scanning of the scanning operation 1 and the scanning operation 2 of the probe 4 of the comparative example.
Since the irradiation point a of the probe 4 in the comparative example is electronically scanned in synchronization with the encoder output of the X-axis scanner 21, the positions in the X-axis direction match between the scan operation 1 and the scan operation 2 (for example,). Xn coordinates). However, the irradiation points b, c, d, e, f, and g are slightly displaced positions depending on the scanning direction.

Here, the display of the ultrasonic image of the reflected wave of the ultrasonic beam irradiated by the probe 4 will be described in detail.
FIG. 4A is a diagram showing an example of a time change in signal intensity in a reflected wave processed by the reflected wave signal processing unit 15. The reflected wave signal processing unit 15 obtains a displacement (amplitude) of the signal intensity of the reflected wave in a predetermined time width centered on a time corresponding to a predetermined depth of the subject 8 to be inspected.

FIG. 4B is a diagram illustrating that the reflected wave image generation unit 16 converts the signal intensity of the reflected wave for each irradiation point into a gradation degree of 0 to 255. When the signal intensity of the reflected wave is 0 (displacement is 0), it is black with a gradation of 255, and when the signal intensity of the reflected wave is maximum (displacement is maximum), it is white with a gradation of 0. As the displacement) increases, the degree of gradation is reduced (intermediate value) to make it gray.

Next, the ultrasonic images obtained by electronically scanning with the probe 4 of the comparative example will be described with reference to FIGS. 4C and 4D.
FIG. 4C is a diagram showing the positional relationship between the irradiation point of the ultrasonic beam of the probe 4 and the subject 8 having three strip-shaped regions having different reflectances as shown in the figure. The first irradiation point of the electron scan of the probe 4 is in each of the three regions having different reflectances, but since the electron scan is performed while the probe 4 is moving, the last irradiation point of the electron scan is adjacent. It is in the strip area.

FIG. 4D is a diagram showing an ultrasonic image obtained by an electronic scan in FIG. 4C.
At this time, the reflected wave image generation unit 16 uses the reflected wave from the subject 8 detected by one electronic scan of the probe 4 as the reflected wave of the ultrasonic beam having the same position (scanning row) in the X-axis direction. , The signal intensity of the reflected wave is calculated, a shade image is obtained, and the display unit 17 displays it as an ultrasonic image. Therefore, a shade image having a reflectance distribution different from that of the subject 8 described with reference to FIG. 4C is displayed.

As will be described in detail below, the ultrasonic image of the irradiation point in the adjacent strip area leads to a display shift at the position where the outward path and the return path of the scanning operation in the X-axis direction are switched.

5A and 5B are diagrams illustrating an example of displaying an ultrasonic image when the probe 4 of the comparative example is reciprocated.

FIG. 5A is a diagram showing the position of the irradiation point of the electron scan of the probe 4 when the outer shape of the subject 8 is used as the scanning area.
As described with reference to FIG. 3B, since the electronic scan is performed in synchronization with the encoder output of the X-axis scanner 21, the positions in the X-axis direction match between the scan operation 1 and the scan operation 2 (for example, Xn coordinates). .. However, the irradiation points b, c, d, e, f, and g are slightly displaced positions depending on the scanning direction. Therefore, the irradiation points e, f, and g of the final electronic scan of the scan operation 1 irradiate the outside of the subject with the ultrasonic beam.

FIG. 5B is a diagram showing an ultrasonic image obtained by the electronic scan of FIG. 5A.
The reflected wave image generation unit 16 displays the reflected wave from the subject 8 detected by one electronic scan of the probe 4 as the reflected wave of the ultrasonic beam having the same position (scanning row) in the X-axis direction. , The irradiation points e, f, and g are displayed as ultrasonic images of the Xn coordinates of the subject 8.

Since the reflected wave of the subject 8 and the reflected wave outside the subject have different signal intensities, the reflected wave image corresponding to the irradiation points e, f, and g is displayed as a different density image and is visually recognized as a deviation of the image information. Ru. In FIG. 5B, for the sake of explanation, the reflected wave image of the subject 8 is white, and the reflected wave image outside the subject is black.

The array-type ultrasonic imaging apparatus 1 of the embodiment will be described below.

FIG. 6A is a diagram illustrating an irradiation point of the ultrasonic beam of the probe 4 of the embodiment.
The irradiation points a, b, c, d, e, f, and g are irradiation points of the ultrasonic beam by electron scanning of the oscillators a, b, c, d, e, f, and g of the probe 4. In particular, the irradiation point a is an irradiation point corresponding to the origin of the scanning area, and is an irradiation point of the first ultrasonic beam of the electronic scan synchronized with the encoder output of the X-axis scanner 21 during the scanning operation.

The electronic scan of the probe 4 is performed during the continuous movement of the scan operation. The solid rectangle in FIG. 6A indicates the position of the probe 4 when the ultrasonic beam is first irradiated, and the broken line rectangle indicates the position of the probe 4 when the ultrasonic beam is finally irradiated.

The probe 4 irradiates the irradiation point a with the ultrasonic beam and then irradiates the irradiation point g at the other end of the electron scan with the ultrasonic beam by the timing processing unit 13 (see FIG. 1). Next, the ultrasonic beam is irradiated to the irradiation point b on the center side of the irradiation point a. In this way, the probe 4 alternately irradiates ultrasonic beams from the irradiation points at the opposite ends toward the irradiation points at the central portion in order to perform an electronic scan.

In other words, the probe 4 irradiates the ultrasonic beam so that the irradiation point of the ultrasonic beam has a dogleg shape or an inverted shape depending on the direction of the scanning operation.

FIG. 6B is a diagram showing the positions of the irradiation points of the ultrasonic beam in the scanning areas of the scanning operation 1 and the scanning operation 2 of the probe 4.
Since the irradiation point a of the probe 4 is electronically scanned in synchronization with the encoder output of the X-axis scanner 21, the positions in the X-axis direction coincide with the scan operation 1 and the scan operation 2, and the irradiation points b and c are aligned. , D, e, f, and g are slightly displaced positions depending on the scanning direction.

7A and 7B are diagrams illustrating an example of displaying an ultrasonic image when the probe 4 of the comparative example is reciprocated.

FIG. 7A is a diagram showing the position of the irradiation point of the electron scan of the probe 4 when the outer shape of the subject 8 is used as the scanning area.
As described with reference to FIG. 6B, the irradiation point a of the probe 4 is electronically scanned in synchronization with the encoder output of the X-axis scanner 21, so that the positions in the X-axis direction are different between the scan operation 1 and the scan operation 2. At the same points, the irradiation points b, c, d, e, f, and g have an inverted or doglegged irradiation point of the ultrasonic beam depending on the scanning direction. As a result, the irradiation points c, d, and e of the final electronic scan of the scan operation 1 irradiate the outside of the subject with the ultrasonic beam.

FIG. 7B is a diagram showing an ultrasonic image obtained by the electronic scan of FIG. 7A.
The reflected wave image generation unit 16 displays the reflected wave from the subject 8 detected by one electronic scan of the probe 4 as the reflected wave of the ultrasonic beam having the same position (scanning row) in the X-axis direction. , The irradiation points c, d, and e are displayed in black as an ultrasonic image of the Xn coordinates of the subject 8. For the sake of explanation, the reflected wave image of the subject 8 is white, and the reflected wave image outside the subject having different signal intensities of the reflected wave is black.

In this way, in the final electronic scan of the forward processing immediately before the shift processing, the image near the edge boundary with the recovery processing is displayed in white, while the forward processing of the first electronic scan of the recovery processing is performed. The image near the edge boundary is also displayed in white. As a result, the image near the boundary between the forward and backward edges is displayed in white, which has the same gradation. That is, by irradiating the ultrasonic beam so that the irradiation point of the ultrasonic beam has a dogleg shape or an inverted shape according to the direction of the scan operation described with reference to FIG. 6A, the outward path and the return path of the scan operation are performed. In the image near the edge boundary, the gradation is the same, and it is possible to suppress the deviation of the generated image information and display an image close to the real image of the subject. That is, it is possible to correct the deviation of the display of the ultrasonic reflected wave at the position where the outward path and the return path of the scanning operation are switched.

Next, the operation flow of the plane scanning of the array type ultrasonic imaging apparatus 1 will be described with reference to FIG.
In step S81, the control device 10 acquires the scanning conditions of the position of the origin of the scanning area (XY coordinates), the width (length in the X-axis direction), and the height (length in the Y-axis direction).

In step S82, the mechanical control unit 11 drives the 3-axis scanner 2 to move the probe 4 to the position of the origin of the scanning range.

In step S83, the control device 10 repeats the processing of steps S83 to S811 for the height of the scanning area (Y-axis direction).

In step S84, the mechanical control unit 11 starts the scanning operation of the probe 4 in the X-axis direction of the scanning area by the X-axis scanner 21.

In step S85, the control device 10 repeats the processes of steps S86 to S88 for the width of the scanning area (in the X-axis direction).

In step S86, the control unit 18 of the control device 10 determines whether or not the encoder output of the X-axis scanner 21 notified from the mechanical control unit 11 has been detected, and when the encoder output is detected (Yes in S86), details are given. The electronic scan process of the probe 4 in step S87, which will be described later, is performed. If the encoder output cannot be detected, the process of step S86 is repeated to wait for the encoder output to be detected.

In step S89, the mechanical control unit 11 is moved by the Y-axis scanner 22 of the 3-axis scanner 2 in the Y-axis direction by the scanning width of the electronic scan, and shifts.

In step S810, the mechanical control unit 11 is set to reverse the moving direction (scanning direction) of the probe 4 in the scanning operation started in step S84.
By the above processing, the array type ultrasonic imaging device 1 captures an ultrasonic image of a predetermined scanning area of the subject 8.

FIG. 9 is a flow chart showing details of the electronic scan process of the probe 4 in step S87 of FIG.
In FIG. 9, the number of irradiation points of the probe 4 is n (odd number), the number of irradiation points at one end of the electron scan is 1, and the numbers are numbered in ascending order toward the other end.

In step S91, the timing processing unit 13 (see FIG. 1) repeats steps S92 to S94 from step S92 to (n-1) / 2 while adding one to the variable i.

In step S92, the timing processing unit 13 selects a group of vibrators that irradiate the irradiation point (i) with an ultrasonic beam, and the vibrator operation signal generation unit 14 (see FIG. 1) transmits a vibrator operation signal to the probe 4. Generate and irradiate the irradiation point (i) with an ultrasonic beam.

In step S93, the timing processing unit 13 selects a group of vibrators that irradiate the irradiation point (n + 1-i) with an ultrasonic beam, and the vibrator operation signal generation unit 14 (see FIG. 1) operates the vibrator 4 on the probe 4. A signal is generated and an ultrasonic beam is applied to the irradiation point (n + 1-i).
By repeating steps S92 and S93, the timing processing unit 13 alternately irradiates the ultrasonic beam from the irradiation point at the opposite end toward the irradiation point at the center.

In step S95, the timing processing unit 13 irradiates the irradiation point ((n + 1) / 2) with an ultrasonic beam. That is, the ultrasonic beam is applied to the irradiation point at the center of the electron scan.

By the above processing, the positions of the first irradiation point, the third irradiation point, and the like from one end of the electronic scan toward the center side, and the second irradiation point and the fourth irradiation point toward the center side from the opposite end ends. An ultrasonic beam is applied to the positions of the irradiation points ... In the order of the first irradiation point, the second irradiation point, the third irradiation point, and the fourth irradiation point.

Although FIG. 9 describes the case where the number of irradiation points of the probe 4 is an odd number, in the case of an even number, the variable i is changed from 1 to n / 2, and the variables are changed from step S92 to step S94 in step S91. Repeat while adding 1 to i. Then, the process of step S95 may be deleted.

By the above processing, as shown in FIG. 6B, the point sequence of the irradiation point g which is the irradiation point of the last ultrasonic beam of the electronic scan in the scan operation 1 and the first ultrasonic beam of the electronic scan in the scan operation 2 The deviation of the irradiation point a, which is the irradiation point of the above, from the point sequence of the irradiation point a is smaller than that shown in FIG. 3B.

Therefore, when the control device 10 calculates the signal intensity of the reflected wave and displays it as a shading image, the reflected wave by the electronic scan is regarded as the reflected wave of the ultrasonic beam having the same position (scanning row) in the X-axis direction. It is possible to reduce the deviation of the shaded image at the boundary between the display area by the scan operation 1 and the display area by the scan operation 2.

Further, since the probe 4 alternately irradiates ultrasonic beams from the irradiation points at the opposite ends toward the irradiation points at the central portion to perform an electronic scan, the misalignment of the adjacent irradiation points of the electronic scan is deteriorated. Can be reduced, and the shift of the shaded image in the display area by the scan operation 1 and the display area by the scan operation 2 can be suppressed from becoming apparent.

The array-type ultrasonic imaging device 1 of the embodiment described above can suppress the occurrence of image misalignment of the reflected wave image generated in the forward and backward movements of the scan of the probe 4, and is the image of the subject 8. Ultrasound images with reduced deviation can be acquired at high speed.

The present invention is not limited to the above-mentioned examples, and includes various modifications. The above-described embodiment has been described in detail in order to explain in an easy-to-understand manner in the present invention, and is not necessarily limited to the one including all the configurations described.

1 Array type ultrasonic imaging device 10 Control device 11 Mechanical control unit 12 Transmission / reception command unit 13 Timing processing unit 14 Oscillator operation signal generation unit 15 Reflected wave signal processing unit 16 Reflected wave image generation unit 17 Display unit 18 Control unit 2 3 axes Scanner 21 X-axis scanner 22 Y-axis scanner 23 Z-axis scanner 24 holder 3 sensor 4 probe (ultrasonic array probe)
42 collar 8 subject 91 aquarium 92 units

Claims (9)

An ultrasonic array probe in which a plurality of vibrators are linearly arranged in parallel is reciprocated in a direction perpendicular to the parallel direction of the vibrators while performing an electronic scan in which an ultrasonic beam is applied to a subject in a predetermined scanning order. The scanning operation and the shifting operation of moving the ultrasonic array probe in parallel with the juxtaposed direction of the vibrator perform plane scanning to irradiate the surface of the subject or the laminated boundary surface with an ultrasonic beam to irradiate the subject. It is an array type ultrasonic imaging device that displays the signal strength of the ultrasonic reflected wave from.
In the electronic scan, the ultrasonic beam is radiated to the irradiation point at one end of the electronic scan, and then the ultrasonic beam is radiated to the irradiation point at the other end facing each other. An array-type ultrasonic imaging device characterized in that a plurality of oscillators are selected and irradiated with ultrasonic beams so as to have a scanning order in which ultrasonic beams are alternately irradiated toward each other . In the array type ultrasonic imaging apparatus according to claim 1,
An oscillator operation signal generation unit that controls the transmission and reception of ultrasonic waves of the oscillator group of the ultrasonic array probe for each irradiation position of the ultrasonic beam.
A timing processing unit that selects the oscillator group corresponding to the scanning order of the electronic scan, and
A transmission / reception command unit that commands the oscillator operation signal generation unit to generate an oscillator operation signal via the timing processing unit and starts the electronic scan of the ultrasonic array probe.
An array-type ultrasonic imaging device including a control unit that controls a transmission / reception command unit in synchronization with a scanning operation of the ultrasonic array probe. In the array type ultrasonic imaging apparatus according to claim 2 ,
The timing processing unit arranges the vibrator group so that the irradiation point of the ultrasonic beam is apparently doglegged or inverted in the direction of travel of the ultrasonic array probe. An array-type ultrasonic imaging device characterized by selection. In the array type ultrasonic imaging apparatus according to claim 2 ,
The control unit
The coordinate system in which the ultrasonic array probe scans the subject in a plane is defined as the X-axis direction in the direction perpendicular to the juxtaposed direction of the oscillator of the ultrasonic array probe, and the Y-axis direction in the juxtaposed direction of the transducer. , When the first irradiation point of the ultrasonic beam to be scanned in a plane is set as the coordinate origin,
An array-type ultrasonic imaging apparatus characterized in that the X-coordinate position of the start position of the electronic scan immediately before the shift operation and the X-coordinate position of the start position of the electronic scan immediately after the shift operation are equal to each other. In the array type ultrasonic imaging apparatus according to claim 1,
The ultrasonic reflected wave from the subject is received at each irradiation position of the ultrasonic beam to obtain the signal intensity of the reflected wave, and the signal intensity is set to a predetermined position in the display area divided into a rectangular shape corresponding to the plane scanning. An array-type ultrasonic imaging device characterized by displaying an image of a corresponding density. In the array type ultrasonic imaging apparatus according to claim 1,
An array-type ultrasonic imaging device including a reflected wave signal processing unit that calculates the signal intensity of the reflected wave of the ultrasonic beam received by the vibrator. In the array type ultrasonic imaging apparatus according to claim 6 ,
The signal intensity of the reflected wave is calculated as the reflected wave of the ultrasonic beam having the same position in the X-axis direction from the reflected wave from the subject detected by one electronic scan of the ultrasonic array probe, and the reflection to obtain the grayscale image. Wave image generator and
An array-type ultrasonic imaging apparatus comprising: a display unit for displaying a light and shade image obtained by the reflected wave image generation unit as a light and shade image of a reflected wave of an ultrasonic beam scanned in a plane of a subject. An array type super that displays the signal intensity of the ultrasonic reflected wave from the subject by sequentially irradiating the subject with the ultrasonic beam of the ultrasonic array probe in which multiple oscillators are arranged side by side in a linear manner and performing an electronic scan. It is a control method for sound wave imaging equipment.
One from each end so that the subject is irradiated with an ultrasonic beam at one end of the electronic scan in a predetermined scanning order, and then the ultrasonic beam is irradiated at the opposite end of the irradiation point. While irradiating the ultrasonic beams by selecting the plurality of transducers so that the scanning order is such that the ultrasonic beams are alternately irradiated toward the central part, the directions of the transducers of the ultrasonic array probe are arranged side by side. The first step of continuously moving the ultrasonic array probe at a predetermined speed in a direction perpendicular to the
A shift step that moves the ultrasonic array probe in parallel with the parallel direction of the oscillators by the scanning width of the electronic scan, and a shift step.
One from each end so that the subject is irradiated with an ultrasonic beam at one end of the electronic scan in a predetermined scanning order, and then the ultrasonic beam is irradiated at the opposite end of the irradiation point. While irradiating the ultrasonic beams by selecting the plurality of transducers so that the scanning order is such that the ultrasonic beams are alternately irradiated toward the central part, the ultrasonic beams are irradiated in the opposite direction to the first step. Including a second step of continuously moving the ultrasonic array probe at a predetermined speed.
By repeating the first step, the shift step, and the second step, the entire surface of the subject is electronically scanned.
A control method for an array-type ultrasonic imaging device. In the control method of the array type ultrasonic imaging apparatus according to claim 8 ,
The step of detecting the presence / absence of the encoder output of the X-axis scanner that scans the ultrasonic array probe, and
A control method for an array-type ultrasonic imaging device, comprising a step of irradiating a first irradiation point at one end of an electronic scan with an ultrasonic beam when the encoder output is detected.

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