JP2003322646A - Ultrasonic image apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ultrasonic image apparatus of a simple constitution capable of accurately matching a focus area with a location to be measured even if a slope, etc., are present in a body to be inspected, measuring any interface of the body to be inspected at high resolution, and performing measurement in a short time. <P>SOLUTION: The ultrasonic image apparatus is provided with an ultrasonic probe 14 for transmitting ultrasonic waves to the body to be inspected 12 and receiving reflected waves; a distance measuring means for measuring the distance between the probe and the body to be inspected; a correcting means for creating data on the shapes of the surfaces and others of the body to be inspected and forming data for correction; and a measuring means for matching the focus area of the ultrasonic waves with a part to be measured on the basis of the data for correction from the correcting means and, by reflected waves from each location of the part to be measured, measuring the locations. When measurement is performed by making the probe scan the surfaces of the body to be inspected by the above-mentioned constitution, the focus area of an ultrasonic beam is controlled in such a way as to be matched with the part to be measured of the interior of the body to be measured on the basis of the data for correction provided by the correcting means. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic imaging apparatus, and in particular, it obtains information on the inclination and undulation of a measurement / inspection surface before the original measurement, and puts the information on the inclination and the like into a condition for focusing area. The present invention relates to an ultrasonic imaging apparatus in which the measurement is set and the measurement is performed.

[0002]

2. Description of the Related Art Generally, a focus type ultrasonic probe is used in an ultrasonic imager. The focus type ultrasonic probe is provided with an acoustic lens in a portion that outputs ultrasonic waves. The ultrasonic waves generated from the piezoelectric vibrator are focused by an acoustic lens to form a beam. Using the beam-shaped ultrasonic waves, the surface and the inside of the subject are observed at a fine pitch.

The beam diameter of the beam-like ultrasonic wave d (-6)
dB) is approximately represented by the following formula (Equation 1). As is clear from (Equation 1), the beam diameter depends on the frequency.
The smaller the beam diameter, the higher resolution the measurement can be made.

[0004]

## EQU1 ## d (-6 dB) = 0.705 × λ × f / R where λ: wavelength, f: focal length, R: radius of lens aperture

In the beam-shaped ultrasonic wave, the length of the beam-shaped narrowed portion is called the beam focal depth (L) and is approximately represented by the following equation (Equation 2). The beam focal depth L has a characteristic that it becomes smaller as the frequency becomes higher and the incident angle becomes larger.

[0006]

[Equation 2]

When performing flaw detection measurement on an object in an ultrasonic imaging apparatus, the distance between the object and the probe is adjusted so that the measurement interface is within the depth of focus of the beam. Enables high-resolution measurement. The beam depth of focus forms the focal area, or focal area.

Further, as a publicly known document related to the present invention, Japanese Patent No. 2722087 (issued on March 4, 1998) is cited. The ultrasonic flaw detector disclosed in this document has a configuration suitable for automatic flaw detection of a subject having a complicated surface shape. This ultrasonic flaw detector has a means for matching the direction of the central axis of the beam-shaped ultrasonic waves emitted from the ultrasonic probe with the normal direction at each position on the surface of the subject, and the ultrasonic probe and the subject It is provided with means for measuring the distance to the sample and control means for controlling the distance to be kept constant. With these configurations, even if the surface of the subject is changed in a complicated manner, it is possible to carry out ultrasonic flaw detection while keeping a certain distance and following the surface. On the other hand, assuming that the ultrasonic wave is diffusely reflected and cannot be received by the ultrasonic probe, it is further provided with a means for controlling the distance and the normal direction. The ultrasonic flaw detector according to the above document makes it possible to appropriately follow the surface of the subject even if the surface of the subject has undulations or inclination.

[0009]

When performing measurement with an ultrasonic imaging apparatus, the object to be measured is usually placed on a horizontal surface. On the other hand, depending on the measurement conditions, there is a case where the object is tilted at the time of installation, or naturally tilted, or the subject itself is warped or undulated. Therefore, in the conventional ultrasonic imaging apparatus, when measuring an arbitrary interface inside the subject, as shown in FIG. 14 and FIG. 15, the detection gate is always applied with an arbitrary delay time from the reflected echo wave from the surface. Therefore, the reflected echo wave from the defect or the like is measured. In FIGS. 14 and 15, 101 is a signal related to the transmitted wave, and 102 is a reflected wave 1 from the surface of the subject.
And 103 is an echo signal related to the reflected wave 2 from the interface inside the subject. A first gate 104 having a relatively wide gate width is set corresponding to the echo signal 102, and a second gate 105 is set for the first gate 104. When the echo signal 102 is detected by the first gate 104, the second gate 105 counts a delay time 106 for generating the second gate 105 based on the detection time point. In the example of FIG. 14, the echo signal 102 is detected early in the gate 104, and in the example of FIG.
It was detected late in 04. In these examples, in the case of FIG. 14, the focal region of the beam-shaped ultrasonic wave is aligned with the interface of the subject, so that the echo signal 103 of a desired level is extracted by the second gate 105. In the case of 15, the focal area is not exactly aligned with the outer surface, so that the echo signal 103 is taken out in a attenuated state.

Next, as shown in FIG. 16, when the beam focal depth L of the beam-like ultrasonic wave is small, when the surface height of the subject placed at a predetermined position is different, There arises a problem that a portion to be measured on the subject deviates from the beam focal depth (focal region). In FIG. 16, 201 is a subject and 20
Reference numeral 2 denotes a portion to be measured, such as a joint surface inside the subject 201. As is clear from the coordinate system including the X axis (horizontal axis) and the Z axis (vertical axis: depth direction) in FIG.
Are arranged in an inclined state in the X-axis direction. An ultrasonic probe 203 is arranged at a position above the subject 201, and the ultrasonic beam 203 is emitted from the ultrasonic probe 203 to the surface of the subject 201 from top to bottom. Is irradiated. The ultrasonic probe 204 at the position A moves to the position B by the scanning movement 205 in the X-axis direction. At this time, in the beam-shaped ultrasonic wave 204 emitted from the ultrasonic probe 203, a focal area 206 is shown corresponding to the portion of the beam focal depth 204a. As is clear from FIG. 16, since the subject 201 is inclined downward to the right, the point 202 to be measured at the left end of the subject 201 is in position coincident with the focal area 206 of the beam-shaped focal depth 204a. However, at the right end, the portion 202 to be measured is out of the focal area 206.

Due to the above problems,
It becomes impossible to perform highly accurate measurement over the entire object 201. That is, in this case, with respect to the right half of the subject 201, since the obtained image is not in focus, the problem of poor measurement accuracy is raised.

As an example, an ultrasonic probe often used for measuring a semiconductor package sealed with resin has a frequency of 25 MHz, a focal length of 25 mm, and an opening diameter of 6.4 m.
Taking the example of m, the beam diameter is 0.33 mm and the depth of focus is 7.48 mm. Further frequency is 150 MH
z, the focal length is 5.2 mm, and the aperture diameter is 2 mm, the beam diameter is 0.037 mm and the depth of focus is 0.
It becomes 54 mm. When the frequency becomes high, the depth of focus becomes extremely small, so that a slight tilt or undulation is not allowed in the subject, and the above-mentioned problem becomes remarkable.

Further, as mentioned above, Japanese Patent No. 27220
According to the ultrasonic flaw detector disclosed in Japanese Patent Publication No. 87, it is possible to deal with the case where the subject is tilted.
The above problem can be solved. However, in this ultrasonic flaw detector, the distance between the ultrasonic probe and the subject is measured, control is performed so that the distance is kept constant, and the beam shape transmitted from the ultrasonic probe is further measured. Since it is necessary to perform control so that ultrasonic waves are incident on the surface of the subject in the normal direction, the device configuration becomes complicated, the manufacturing cost is high, and the time required for measurement is long. Cause

An object of the present invention is to solve the above-mentioned problems, and even if the installed subject has tilt, warp, undulation, etc., the focus area is accurately adjusted to the measurement location. An object of the present invention is to provide an ultrasonic imaging apparatus capable of measuring a surface and an arbitrary interface with high resolution and having a simple configuration and in a short time.

[0015]

In order to achieve the above object, an ultrasonic imaging apparatus according to the present invention is constructed as follows.

First ultrasonic imaging apparatus (corresponding to claim 1)
Is an ultrasonic probe that transmits beam-shaped ultrasonic waves to the subject and receives reflected waves from the subject, and the distance between the ultrasound probe and the surface of the subject or any location. A distance measuring means for measuring and data relating to the morphology of the surface of the subject by the signal from the distance measuring means (data of the amount of inclination, profile data relating to an inclined surface or a curved surface) are created,
A correction unit that uses this data for correction during scanning of the measurement, and based on the correction data provided from this correction unit, the focal area of the ultrasonic wave is made to match the measurement target unit in the subject and each position of the measurement target unit is adjusted. And a measuring means for performing measurement at the position by the reflected wave from. According to the above configuration, when performing measurement by scanning the surface of the subject with the probe, the focal area of the ultrasonic beam matches the measurement target portion inside the subject based on the data given from the correction means. The height position of the probe is controlled and adjusted as described above.

Second ultrasonic imaging device (corresponding to claim 2)
In the above-mentioned first configuration, preferably, the distance measuring means acquires the road distance data of two points on both sides of the scanning line, and the correcting means detects the inclination of the object based on the road distance data to detect the object. And is characterized by correcting the distance of the ultrasonic probe.

Third ultrasonic imaging device (corresponding to claim 3)
In the above-mentioned first configuration, preferably, the distance measuring means acquires the distance data by performing distance measurement only in the forward movement, and the correcting means measures the distance data in the backward scanning of the ultrasonic probe. It is characterized by being measured by the measuring means while correcting the distance between the subject and the ultrasonic probe by utilizing it.

Fourth ultrasonic imaging device (corresponding to claim 4)
In the above-mentioned first configuration, preferably, the distance measuring means performs distance measurement on the entire measurement area of the subject to obtain road length data, and the measurement scan after the distance measurement is performed by the correcting means. Is used to correct the distance between the subject and the ultrasonic probe, and the measuring area is entirely measured by the measuring means.

Fifth ultrasonic imaging device (corresponding to claim 5)
In the first configuration described above, preferably, the distance measurement is performed while correcting the distance between the subject and the ultrasonic probe based on the path length data measured by the distance measurement means in the previous scanning line. Measure the path length by means, use the path length data obtained by this measurement to correct the next scanning line, and repeat the path length measurement in each scanning line sequentially,
It is configured to make a measurement.

[0021]

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings.

The configurations, shapes, sizes and arrangement relationships described in the embodiments are merely schematic ones to the extent that the present invention can be understood and put into practice, and numerical values and compositions (materials) of each constituent element. Is only an example. Therefore, the present invention is not limited to the embodiments described below, and can be modified into various forms without departing from the scope of the technical idea shown in the claims.

FIG. 1 is a block diagram showing the configuration of an ultrasonic imaging apparatus according to the present invention. The configuration of the ultrasonic imaging apparatus will be described with reference to FIG. The ultrasonic imaging apparatus 10 includes a scanning mechanism 11 having an XYZ moving mechanism, and a water tank 13 that stores water and in which a subject 12 is placed. X of the scanning mechanism 11
The YZ moving mechanism includes a moving mechanism in each direction of the X axis, the Y axis, and the Z axis. A focus type ultrasonic probe (hereinafter referred to as “probe”) 14 is attached to the scanning mechanism 11 and
2 is located above. The scanning mechanism 11 allows the probe 14 to freely move in each of the X-axis, Y-axis, and Z-axis directions. The probe 14 is moved by the scanning mechanism 11 to perform a main scan on the subject 12 in the X-axis direction and a sub-scan in the Y-axis direction.

The ultrasonic imaging apparatus 10 acquires measurement values for obtaining an A scope image at each measurement point on the subject 12 based on the XY scanning. Further, data for displaying the B-scope image and the display for the C-scope image are generated based on the measurement values related to the A-scope image, and the images for the B-scope image and the C-scope image are displayed.

In the present embodiment, it is assumed that the subject 12 has a defect, a bonding surface, an interface, or the like, which becomes an inspection target portion at a position at a certain depth from the surface thereof.

The scanning mechanism 11 is controlled by the scanning controller 15. The scan controller 15 includes an interface 16
Is controlled by the image processing device 20 having a control function. The probe 14 is connected to the ultrasonic flaw detector 17. The ultrasonic flaw detector 17 includes a transmitter 17a and a receiver 17
b, a clock circuit 17c, and other components such as an oscillator and a pulser / receiver. The ultrasonic flaw detector 17 is also controlled by the image processing apparatus 20 via the interface 16. In response to a control signal from the image processing device 20, the ultrasonic flaw detector 17 drives the probe 14 by sending pulse signals from its transmission terminal to the probe 14 in a predetermined cycle, and To emit ultrasonic waves. At this time, the probe 14 receives the ultrasonic wave reflection echo obtained from the subject 12 with respect to the ultrasonic wave from the probe 14, and converts it into an electric signal. The ultrasonic flaw detector 17 receives the electric signal converted by the probe 14 as an echo reception signal at its reception terminal, and amplifies this. The A / D conversion circuit 18
In response to the control signal from the image processing device 20, the analog signal obtained from the ultrasonic flaw detector 17 is converted into a digital value in 256 steps of 8 bits, for example. The measurement data of the digital value is input to the bus 21 of the image processing device 20. The measurement data is processed by the microprocessor (MPU) 22 of the image processing device 20.

In the above configuration, the ultrasonic imaging apparatus 10
In a normal measurement state at, for example, the probe 14 is
In the X-axis direction, the scanning operation is performed by a fixed unidirectional scan or a reciprocal scan. In the unidirectional scanning, after scanning one line in the X-axis direction, the scanning line returns to the starting point of the one-line scanning and is pitch-fed in the Y-axis direction, and then performs the scanning operation in the same direction as the previous scanning in the X-axis direction. In reciprocal scanning, after scanning one line in the X-axis direction, pitch feed is performed in the Y-axis direction, and scanning is performed in the opposite direction to the previous scan in the X-axis direction. Thus, the surface of the subject 12 is scanned on the XY plane. In this measurement scan, measurement is performed at each measurement point assigned at a predetermined pitch in the scan in the X-axis direction, digitized by the A / D conversion circuit 18, and the measurement data is converted into a digital value in the form of the MP data.
U22 takes in. The MPU 22 detects a peak value in a predetermined gate from these digitized echo signals, and sequentially corresponds to each measurement point in the data area 2 of the memory 23.
It will be stored in 3a.

The memory 23 also stores a peak detection program 23b, a measurement condition setting program 23c, a drive control program 23d, and the like. The peak detection program 23b and the drive control program 23d are the subject 1
2. The inspection measurement 2 is executed, display processing for creating an image is performed based on the measurement data regarding a large number of measurement points obtained by the inspection measurement, the image data for display is stored in the image memory 24, and the display circuit is further displayed. An image of the inspection surface in the subject 12 obtained by the measurement is displayed on the display screen of the CRT (display device) 26 via 25. The CRT 26 is the image processing device 2
It is placed outside 0. Measurement condition setting program 23c
Has a function of setting conditions required for measurement with an ultrasonic beam. In particular, in this embodiment, as will be described later, at a stage before the actual measurement, the distance measurement between the probe 14 and the subject (acquisition of distance data, etc.), the amount of inclination of the subject 12, Measure the surface profile of the subject 12,
Measurement conditions related to scanning are corrected and set based on the information related to the inclination, etc., and measurement points inside the subject (interface, etc.)
In either case, the focal range of the ultrasonic beam is adjusted. A correction means for performing the above correction is realized by the measurement condition setting program 23c. Further, the ultrasonic imaging apparatus 10 has an input device 28 connected to the bus 21 of the image processing apparatus 20 via an interface 27.
Equipped with. The input device 28 is provided with various input keys.

A first measurement example by the ultrasonic imaging apparatus according to the present invention will be described with reference to FIGS. FIG. 2 conceptually shows a scanning state in the first measurement example, FIG. 3 shows a flow chart of a measurement process for carrying out the first measurement example, and FIG. 4 shows a state in which the focus is matched in the first measurement example. Is shown.

In this measurement, the subject 12 has a relatively large shape, is flat, and has an inspection surface such as a bonding surface (interface) inside. It is assumed that the subject 12 is in an inclined arrangement state as shown in FIG. The surface 12a of the subject 12 is, for example, a flat surface, and it is assumed that there is no undulation. A probe 14 is disposed above the subject 12, and an ultrasonic wave emitting portion of the probe 14 faces the surface of the subject 12. Long arrows 31a, 31b, 31c shown on the surface of the subject 12 indicate the loci of main scanning of the probe 14, and short arrows 32a, 32b.
Indicates the locus of sub-scanning of the probe 14. Actually, the main scan and the sub scan occur over the entire surface of the measurement region, but FIG. 2 shows only the initial three main scans and the portions related to the two sub scans. Arrows 31a, 31b and 31c respectively indicate the first, second and third main scans, and arrows 32a, 31b
Each of 32b indicates the first and second sub-scanning (feeding). The right ends of the arrows 31a to 31c are scanning start points, and the left ends are scanning end points. At the start of measurement, the probe 14 is located at the left end 1 _LS of the first main scan 31a. Measurement is performed on the measurement region of the subject 12 based on the main scan and the sub-scan as shown in FIG. 2, and the C scope image is measured by focusing on an arbitrary interface (measurement point) inside the subject 12. To be done.

The measurement process will be described with reference to FIG. At the first stage, the probe 14 moves the first main scan 31
It is located at the left end 1 _LS of a. In the first step S11, the variable N is set and "1" is substituted into the variable N. This variable N represents the number of main scanning. The probe 14 is located at the left end 1 _LS of the main scan 31a, and in the next step S12, the distance from the probe 14 to the point 1 _LS on the surface of the subject 12 is measured. The distance is measured by transmitting a beam-like ultrasonic wave from the probe 14 and receiving an echo wave due to reflection from the point 1 _LS at the probe 14, and transmitting wave signal and echo on the A scope image. The distance is measured based on the temporal relationship of the signals by using the above-mentioned time counting circuit 17c and the like. Data relating to the distance measured for the point 1 _LS is stored in the data area 23a of the memory 23. Next, the probe 14 is moved to the position corresponding to the point 1 _LE . At the time of this movement, the height position of the probe 14 is maintained at the initially set constant height. Next, at the point 1 _LE position,
Similarly, the distance from the probe 14 to the subject surface 12a is measured, and the data related to the distance is stored (step S
13). Based on the distance data stored for the above two points, the amount of inclination of the surface of the subject 12 in the portion related to the main scan 31a is calculated (step S14). Next, at the point 1 _LE , the probe 14 is focused on an arbitrary interface inside the subject 12,
Further, based on the calculated tilt amount, the probe 14 is moved in the main scanning direction from the point 1 _LE to the point 1 _LS in accordance with the tilt of the subject 12, the normal flaw detection measurement is performed, and the image measurement of the C scope image is performed ( Step S16). When the probe 14 is moved from the point 1 _LE to the point 1 _LS in the main scanning 31a, the height position of the probe 14 is controlled and changed. C obtained by measurement
The data of the scope image is stored in the data area 23a of the memory 23.

In the next judgment step S17, it is judged whether or not the flaw detection measurement is completed. NO in determination step S17
In the case of, in step S18, the probe 14 is sub-scanned by a predetermined feed movement amount (arrow 32a), and the next main scanning 31b is performed.
Move it to the position where you want to measure. After that, the variable N
1 is added to the numerical value of (step S19), and step S1
Return to 2. After that, steps S12 to S17 described above regarding the main scanning 32b are repeated. Thus main scanning 32
The flaw detection measurement for b is completed. Judgment step S17
Then, it is again determined whether the flaw detection measurement is completed, and NO
If so, steps S18 and S19 are executed, and the above measurement steps are repeated for the next main scan 32b. If YES is determined in the determination step S17, the measurement operation is ended.

According to the first measurement example described above, the measurement is performed in an image as shown in FIG. 4 in comparison with FIG. 13 which illustrates the conventional problem described above. That is, in the case where the left end and the right end of the subject 12 have different heights and are tilted, the probe is applied to any position of the measurement point (interface or the like) 35 in the tilted state in the subject 12. Child 14
The focal region 37 of the beam-shaped ultrasonic wave 36 emitted from can be accurately matched for measurement. Therefore, according to the first measurement, it is possible to move the focal region 37 in accordance with the inclination of the measurement point 35 and obtain a focused and accurate C-scope image at any of the measurement points 35.

Next, a second measurement example by the ultrasonic imaging apparatus according to the present invention will be described with reference to FIGS. FIG. 5 shows a scanning state in the second measurement example, FIG. 6 shows a flow chart of a measurement process for implementing the second measurement example, and FIG. 7 shows a profile of the form obtained in the second measurement example.

In this second measurement example, the subject 12 is placed under the same conditions as those used in the first measurement example. The subject 12 has an inspection surface such as an interface inside. The subject 12 is in an inclined arrangement state as shown in FIG. Similarly, a probe 14 is provided above the subject 12.
Are arranged. Long arrows 31a, 31b, 31c shown on the surface of the subject 12 indicate the main scanning locus of the probe 14, and short arrows 32a, 32b indicate the sub scanning locus of the probe 14. The right end of each of the arrows 31a to 31c is the measurement scanning start point, and the left end is the measurement scanning end point. At the time of starting the measurement, the probe 14 moves to the left end 1 of the first main scan 31a.
It is located in the upper position corresponding to the _LS . Measurement is performed on the measurement region of the subject 12 based on the main scanning and the sub-scanning as shown in FIG. 5, and the C scope image is measured by focusing on an arbitrary interface inside the subject 12. The above points are the same as in the first measurement example described above.

In the second measurement example shown in FIG. 5, arrows 41a, 41b and 41c drawn by broken lines are further shown. These arrows 41 a to 41 c are measurement movements for creating a profile of the surface portion of the subject 12 to be measured, and the probe 14 for measuring the distance between the probe 14 and the subject 12. Shows the movement of. When performing the measurement movement by the probe 14 indicated by the arrows 41a to 41c, the height control of the probe 14 is not performed, and the probe 1
The height position of 4 is maintained at a constant height in the initial state. In this second measurement example, as indicated by arrows 41a to 41c, the profile of the surface of the subject corresponding to the interface to be measured is measured before the actual measurement.

The measurement processing process of the second measurement example will be described with reference to FIG. In the first stage, the probe 14 is the first
Is arranged above the left end 1 _LS of the main scan 31a. In the first step S21, the variable N is set and "1" is substituted into the variable N. This variable N represents the number of main scanning. The probe 14 is the left end 1 _LS of the main scanning 31a.
In the position. In the next step S22, the probe 14
Is moved from the point 1 _LS to a desired position in a section from the point 1 _LS to the point 1 _LE at a constant height above the surface of the subject 12, and the probe 14 and the subject surface 12a are moved in the section. The distance between the two is measured and a profile of the surface of the subject is created. The measurement of the distance is performed using the timing circuit 17c or the like as described in the first measurement example. FIG. 7 shows an example 42 of the created profile data. In Figure 7, the horizontal axis is X
The axis and the vertical axis mean time. In the illustrated example shown in FIG. 5, the subject 12 is inclined downward to the right, whereas in FIG. 7, the time is longer in the right portion. This means that the measured distance is large in the right part. The degree of inclination of the line 42a shown in FIG. 7 represents the amount of inclination. The profile data 42 is stored in the data area 23a of the memory 23.

In the next step S23, the probe 14 holds the position in the height direction at a constant position, and the main scanning 31 is performed.
It is moved to the position corresponding to the scanning start point 1 _LE of a. Then the probe 14 at point 1 _LE, focus on any interface of the inside of the subject 12, the point 1 from point 1 _LE in accordance with the inclination of the object 12 based on the profile data 42 is created and stored _The main scanning 31a is moved up to _LS , ordinary flaw detection measurement is performed, and image measurement of the C scope image is performed. The data of the C scope image obtained by the measurement is stored in the data area 23a of the memory 23.

In the next judgment step S24, it is judged whether or not the flaw detection measurement is completed. NO in determination step S24
In this case, in step S25, the probe 14 is sub-scanned by a predetermined movement amount (arrow 32a), and is moved to a position where the next main scanning 31b should be performed. After that, 1 is added to the numerical value of the variable N and the process returns to step S26. After that, main scanning 31
The steps S22 to S24 described above for b are repeated. Thus, the flaw detection measurement for the main scan 31b is completed. In the judgment step S24, it is judged again whether or not the flaw detection measurement is completed, and if NO, the steps S25, S
26 is executed, and the above distance measurement and measurement steps are repeated for the next main scan 31c. Judgment step S
As long as 24 is NO, the above processing is continued. If YES is determined in the determination step S24, the measurement operation is ended.

According to the second measurement example described above, the distance measurement is performed on the outward path, so that the left end and the right end of the subject 12 have different heights and an inclination occurs, as in the first measurement example. In this case, the measurement can be performed by accurately matching the focal areas of the ultrasonic beams emitted from the probe 14 with any of the measurement points in the subject 12 in an inclined state. Therefore, also by the second measurement, it is possible to obtain a focused and accurate C scope image by moving the focal region in accordance with the inclination of the measurement point.

Next, a third measurement example by the ultrasonic imaging apparatus according to the present invention will be described with reference to FIGS. Figure 8
10 shows a scanning state in the third measurement example, FIG. 9 shows a flow chart of measurement processing for carrying out the third measurement example, and FIG.
Shows the profile of the form obtained in the third measurement example.

In the third measurement example, the subject 51 is a tubular member.
Is. In the description of the third measurement example, the second measurement example and
The same elements will be described with the same reference numerals. Subject 51
Has an inspection surface such as a defect or an interface inside. Subject
51 is arranged substantially horizontally as shown in FIG.
However, since it is a tubular member, the measurement surface is cylindrical.
It has roundness. The upper position of the subject 51 is similarly searched.
The tentacles 14 are arranged. Shown on the surface of subject 12
The long arrows 31a, 31b, and 31c that are drawn are the main members of the probe 14.
The trajectories of scanning are shown, and the short arrows 32a and 32b indicate the probe 1.
4 shows a locus of sub-scanning. The right ends of the arrows 31a to 31c are
It is the measurement scanning start point, and the left end is the measurement scanning end point.
At the time of starting the measurement, the probe 14 moves the first main scan 31a.
Left edge 1 _LSIs arranged at an upper position corresponding to. Figure 8
The subject 51 based on the main scan and the sub-scan as shown in FIG.
Measurement is performed on the measurement area of
The C-scope image is measured by focusing on an arbitrary interface of the part
It

In the third measurement example shown in FIG. 8, arrows 41a, 41b and 41c drawn by broken lines are shown. These arrows 41 a to 41 c are measurement movements for creating a profile of the surface portion of the subject 12 to be measured, and the probe 14 for measuring the distance between the probe 14 and the subject 12. Shows the movement of. Arrows 41a-41
When performing the measurement movement by the probe 14 shown by c, the height control of the probe 14 is not performed and the height position of the probe 14 is maintained at a constant height position in the initial state. It

The measurement processing process of the third measurement example will be described with reference to FIG. In the first stage, the probe 14 is moved to the initial position (step S31). The initial position is, for example, a position above the left end 1 _LS of the first main scan 31a. In the next step S32, the probe 14 moves the subject 5
1 is moved from an initial position to a desired position at a constant height above the surface, the distance between the probe 14 and the subject surface is measured in that section, and a profile of the subject surface is created. . The measurement of the distance is performed using the timing circuit 17c or the like as described in the first measurement example. FIG. 10 shows an example 52 of the created profile data. In FIG. 10, the horizontal axis represents the X axis and the vertical axis represents time. In the example shown in FIG. 10, the distance is long on both sides of the subject 51 and the distance is short at the center. The degree of bending of the curve 52a shown in FIG. 10 represents the roundness of the surface of the subject. The profile data 52 is stored in the data area 23a of the memory 23.
Memorized in.

In the next judgment step S33, it is judged whether or not the target area for the flaw detection measurement is completed. Unless completed, step S34 is executed to move the probe 14 by the feed (sub-scanning) distance determined in the Y-axis direction. Then, step S32 is repeated. The above processing is continued until the creation and storage of the profile relating to the target area for flaw detection measurement are completed. In the distance measurement by the probe 14, the arrows 31a, 31b, 31c described above are used.
The probe 14 is moved according to the movement locus shown in FIG. In the above distance measurement, the height position of the probe 14 is maintained at a constant height, and the height position is not controlled.

If YES is determined in the determination step S33, the probe 14 is moved to the initial position for measurement scanning (step S35). This initial position is a position corresponding to the right end 1 _LE of the first main scanning 31a described above.
In the next step S36, the probe 14 is focused on an arbitrary interface inside the subject 51 at the point 1 _LE , and is fitted to the curved surface of the subject 51 based on the profile data 52 created and stored. The main scanning 31a is moved from the point 1 _LE to the point 1 _LS , ordinary flaw detection measurement is performed, and image measurement of the C scope image is performed. The data of the C scope image obtained by the measurement is stored in the data area 23a of the memory 23.

In the next judgment step S37, it is judged whether or not the flaw detection measurement is completed. NO in determination step S37
In this case, in step S38, the probe 14 is sub-scanned by a predetermined movement amount in the Y-axis direction (arrow 32a), and is moved to a position (point _2LE ) where the next main scanning 31b should be performed (step S38). . After that, step S36 described above regarding the main scanning 31b is repeated. Thus, the flaw detection measurement for the main scan 31b is completed. Judgment step S3
At 7, it is judged again whether or not the flaw detection measurement is completed.
When it is O, steps S38 and S36 are executed, and the above distance measurement and measurement steps are repeated for the next main scanning 31c. As long as the determination step S37 is NO, the above-described measurement processing by scanning is continued. When YES is determined in the determination step S37, the measurement operation is ended.

According to the third measurement example described above, first, the probe 14 is held at a constant height position and the distance is measured over the entire measurement area of the curved surface of the subject 51 to create profile data.・ Memorization was performed, and after that, flaw detection measurement was performed using profile data. Therefore, the measurement can be performed by accurately matching the focal areas of the ultrasonic beams emitted from the probe 14 to any of the measurement points. Therefore, also by the third measurement, it is possible to move the focal region in accordance with the inclination of the measurement location and obtain a focused and accurate C scope image.

Next, a fourth measurement example by the ultrasonic imaging apparatus according to the present invention will be described with reference to FIGS. 11 to 13. FIG. 11 shows a scanning state in the fourth measurement example, and FIG.
Shows a flow chart of the measurement process for implementing the measurement example of
FIG. 13 is a diagram for explaining a profile obtained by the scanning operation in the fourth measurement example. In the fourth measurement example, the subject is a plate-shaped member. In the description of the fourth measurement example, the first
The same elements as those in the measurement examples and the like are given the same reference numerals.

In this fourth measurement example, it is assumed that the subject 12 is placed under the same conditions as those used in the first measurement example. The subject 12 has an inspection surface such as an interface inside. The subject 12 is in an inclined arrangement state as shown in FIG. A probe 14 is similarly arranged above the subject 12. The long arrows 61a, 61b, 61c, 61d, ... Shown on the surface of the subject 12 indicate the loci of main scanning of the probe 14, and the short arrows 62a, 62.
b, ... Show the sub-scanning loci of the probe 14. Arrow 61a
˜61d are the trajectories of the first main scanning in which the broken line arrow 61a only measures the distance, and the solid line arrows 61b to 61d.
d is the second and subsequent loci for both scanning for measurement and distance measurement. In each arrow, the end where the arrow is drawn is the end point, and the other end is the start point.

At the start of the first measurement, the probe 14 is located at the upper position corresponding to the left end of the first main scan 61a. Measurement is performed on the entire measurement region of the subject 12 based on the main scanning and sub-scanning operations as shown in FIG. 11, and the C scope image is measured by focusing on an arbitrary interface inside the subject 12. To be done.

In the fourth measurement example, one arrow 61a drawn with a broken line and a plurality of arrows 61b to 61 drawn with a solid line.
As shown separately by d, the operation of each main scan is set as follows. This will be described with reference to FIG. Arrow 61a corresponding to the first (first line) outward path
In the main scan indicated by, only the distance is measured. This state is shown in FIG. That is, (A) of FIG.
In the left diagram of FIG. 1, the probe 14 is moved with respect to the inclined surface 12a of the subject 12 without changing its height position, and the distance between the probe 14 and the surface of the subject 12 is measured. Data relating to the profile 63 as shown in the right diagram of FIG. 13A is obtained based on the measured data of the distance from the surface of the subject 12. This profile data is a surface profile at the location on the surface of the subject indicated by the arrow 61a.

On the return path of the first line, as shown by the arrow 61b, the main scanning for measurement is started together with the distance measurement described above. At the starting point of the probe 14, the height position is adjusted based on the data obtained by the distance measurement described above, and in the return path of the first line, the height is as constant as possible with respect to the surface of the subject 12. The main scan (arrow 61b) is performed while being held so that the main position is reached. At this time, the subject 12
The measurement is performed in a state in which the focal region of the ultrasonic waves is aligned with the interface to be originally measured in (3), and at the same time, the distance measurement is performed. The state of main scanning related to the return path of the first line indicated by the arrow 61b is shown in the left diagram of FIG. With this, the interface measurement is performed and the distance measurement is performed,
As a result, the profile 64 shown in the right diagram in FIG. 13B is obtained. The profile 64 shown on the right side of FIG. 13B shows an example in which there is no change in the inclination or warpage of the surface of the subject 12 in the main scan in the returning path of the first line. After that, the same main scanning as the returning main scanning of the first line is performed on the outward (arrow 61c) and returning (arrow 6) of the second line.
1d) The main scanning is performed in the outward and return passes of the third line and the forward and return passes in the subsequent lines. If the inclination or warpage of the surface of the subject 12 is constant and the same on the second and subsequent lines, the surface profile obtained by distance measurement is the same as that shown in the right diagram of FIG. 13B. In this case, the movement trajectory of the probe 14 on the XZ plane of the previous line may be traced and scanned. On the other hand, when there is a change in the inclination or warpage on the surface of the subject as compared with the previous main scanning line, it is necessary to perform correction on the next main scanning line. FIG. 13C shows a surface profile 65 obtained by distance measurement when there is a change in inclination or warpage on the surface of the subject compared to the previous main scanning line. The shaded portion 66 is the changed portion, and this portion is the correction amount for the probe locus during the previous line scanning.

The measurement processing process of the fourth measurement example will be described with reference to FIG. First, 1 is assigned to the variable N (step S41). In the next step S42, the distance from the probe 14 to the surface of the subject 12 is measured for the Nth or first scanning line. Based on this distance measurement, a profile relating to the inclination of the surface of the subject 12 is created, and the data related to the profile is stored in the memory. Next, in step S43, focusing is performed at a desired position on the return path of the first line based on the created profile data, and distance measurement is performed while scanning. With this, a profile is created, and at the same time, the locus (measurement data) of the probe 14 on the XZ plane is saved.

In the next judgment step S44, it is judged whether or not the numerical value of the variable N is the final line. Step S
At 45, the numerical value of N is incremented by 1. As a result, 2
Main scanning is performed on the outward path of the line. Step S
At 46, sub-scanning is performed in the Y-axis direction. The probe 14 that has moved to the position of the second line starts main scanning for the forward path and the backward path for the second line (step S47). In the main scanning of the second line, step S47
Then, the difference between the profile of the previous scanning line (N−1th) and the constant scanning from the probe 14 to the subject 12 is calculated. Next, a distance correction value is obtained from the locus of the probe 14 on the previous scanning line on the XZ plane and the calculated difference (step S48). Based on the above distance correction value, the distance from the probe 14 to the object 14 is measured while scanning one line for the second line to create a profile, and at the same time, the XZ of the probe 14 is measured. The trajectory on the plane is measured and saved (step S49). Through the above steps S47 to S49, the scanning and measurement processing regarding the main scanning of the forward and return paths of the second line is performed.

Then, the process returns to step S44. Unless it is the final line, steps S45 to S49 are similarly executed for the forward and return passes of the next third line. When it is determined that the line is the final line in the determination step S44, the process ends. Before the final line is determined, steps S45 to S49 are executed for each line.

According to the fourth measurement example described above, scanning for measurement is performed while performing distance measurement for obtaining information about the inclination of the surface of the subject 14 in each main scanning line except for the first line. I'm trying to do. In this measurement example, 1
On the assumption that there is no large difference in the shape, that is, the profile of the object 12 between one scanning line and the adjacent scanning line, the distance measurement (distance measurement between the probe and the object, (Acquisition of path length data) is performed, and scanning is performed on the next scanning line while using the distance data. Also by the fourth measurement described above, it is possible to obtain a focused and accurate C scope image by moving the focal region according to the inclination or warpage of the measurement location. Furthermore, the measurement time can be shortened.

In the above embodiment, the distance measurement and the measurement scan are performed using a single probe. However, for example, two probes are prepared and the distance measurement and the measurement scan are performed separately. It can also be configured to be performed at the same time.

[0059]

As is apparent from the above description, according to the present invention, the distance between the probe and the subject is measured and the path length data is acquired in the ultrasonic imaging apparatus before measurement scanning is performed. Since the correction data is prepared as the path length data, and the measurement scan is performed while adjusting the focal area of the ultrasonic beam to the measurement target portion of the subject by using the correction data, tilt, warp, swell, etc. in the subject Even if there is, it is possible to measure the surface of the subject and the arbitrary interface with high resolution by accurately adjusting the focal area to the measurement location. Further, according to the present invention, it is possible to perform the measurement with a simple configuration and in a short time.

[Brief description of drawings]

FIG. 1 is a block diagram showing a system configuration of an ultrasonic imaging apparatus according to the present invention.

FIG. 2 is a scanning state diagram showing a first measurement example by the ultrasonic imaging apparatus according to the present invention.

FIG. 3 is a flowchart of a measurement process that implements a first measurement example.

FIG. 4 is a measurement state diagram in a focused state based on a first measurement example.

FIG. 5 is a scanning state diagram showing a second measurement example by the ultrasonic imaging apparatus according to the present invention.

FIG. 6 is a flowchart of a measurement process that implements a second measurement example.

FIG. 7 is a diagram showing profile data relating to the surface of a subject obtained by distance measurement according to a second measurement example.

FIG. 8 is a scanning state diagram showing a third measurement example by the ultrasonic imaging apparatus according to the present invention.

FIG. 9 is a flowchart of a measurement process that implements a third measurement example.

FIG. 10 is a diagram showing profile data relating to the surface of a subject obtained by distance measurement according to a third measurement example.

FIG. 11 is a scanning state diagram showing a fourth measurement example by the ultrasonic imaging apparatus according to the present invention.

FIG. 12 is a flowchart of a measurement process that implements a fourth measurement example.

FIG. 13 is a diagram for explaining scanning characteristics according to a fourth measurement example with reference to a profile.

FIG. 14 is a waveform diagram showing a first example of measurement by a conventional ultrasonic imaging apparatus.

FIG. 15 is a waveform diagram showing a second example of measurement by a conventional ultrasonic imaging apparatus.

FIG. 16 is a diagram illustrating a problem of measurement by a conventional ultrasonic imaging apparatus.

[Explanation of symbols]

10 Ultrasonic imaging equipment 11 Scanning mechanism 12 subject 13 aquarium 14 Ultrasonic probe 15 Scanning control device 17 Ultrasonic flaw detector 20 Image processing device 22 MPU 23 memory 35 measurement points 36 beam ultrasound 37 Focus area 51 subject

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Noboru Yamamoto             Hitachi Construction Machinery F, 650 Kintatemachi, Tsuchiura City, Ibaraki Prefecture             Inside Vinetech Co., Ltd. (72) Inventor Ken Takeuchi             Hitachi Construction Machinery F, 650 Kintatemachi, Tsuchiura City, Ibaraki Prefecture             Inside Vinetech Co., Ltd. (72) Inventor Makoto Ishijima             Hitachi Construction Machinery F, 650 Kintatemachi, Tsuchiura City, Ibaraki Prefecture             Inside Vinetech Co., Ltd. (72) Inventor Naoya Kawakami             Hitachi Construction Machinery F, 650 Kintatemachi, Tsuchiura City, Ibaraki Prefecture             Inside Vinetech Co., Ltd. F term (reference) 2F068 AA02 AA06 AA32 AA38 BB01                       BB25 CC00 DD07 EE01 FF03                       FF12 FF14 FF18 FF25 HH01                       JJ03 JJ13 KK12 LL02 NN02                       PP06 PP31 QQ01 QQ05 RR02                       RR13                 2G047 AB01 AB04 AB05 AC10 BA03                       BB06 BC08 BC09 BC18 CA01                       DA01 DA02 DA03 DB03 DB12                       DB16 EA01 EA09 EA14 GA03                       GA06 GF18 GG02 GG09 GG19                       GG24 GG41

Claims (5)

[Claims] 1. An ultrasonic probe that transmits a beam-shaped ultrasonic wave to a subject and receives a reflected wave from the subject, and measures a distance between the ultrasonic probe and the subject. Distance measuring means, and correction means for creating data relating to the morphology of the surface of the subject by a signal from the distance measuring means,
Measuring means for matching the focal region of the ultrasonic wave to the measurement target portion in the subject based on the data given from the correction means and performing measurement at the position by the reflected wave from each position of the measurement target portion An ultrasonic imaging apparatus comprising: 2. The distance measuring means acquires road distance data of two points on both sides of a scanning line, and the correcting means detects inclination of the object based on the path distance data to detect the object and the object. The ultrasonic imaging apparatus according to claim 1, wherein the distance of the acoustic probe is corrected. 3. The distance measuring means performs distance measurement only in forward movement to obtain road distance data, and the correcting means uses the distance data in scanning of the ultrasonic probe on the return path. The ultrasonic imaging apparatus according to claim 1, wherein the measurement is performed while correcting the distance between the subject and the ultrasonic probe. 4. The distance measuring means performs distance measurement on the entire measurement area of the subject to obtain road distance data, and the correction means uses the distance data in a measurement scan after the distance measurement. The ultrasonic imaging apparatus according to claim 1, wherein the measuring area is entirely measured by the measuring means while correcting the distance between the subject and the ultrasonic probe. 5. The distance measurement means measures the distance while correcting the distance between the subject and the ultrasonic probe based on the distance data measured by the distance measurement means in the previous scanning line. Measure and use the path length data obtained by this measurement to correct the next scan line,
The ultrasonic imaging apparatus according to claim 1, wherein the path length measurement is repeated in each scanning line to perform the measurement.