U.S. patent application number 13/372003 was filed with the patent office on 2012-06-07 for ultrasonic inspection equipment and ultrasonic inspection method.
This patent application is currently assigned to HITACHI, LTD.. Invention is credited to Atsushi BABA, So KITAZAWA, Naoyuki KONO.
Application Number | 20120137778 13/372003 |
Document ID | / |
Family ID | 40933157 |
Filed Date | 2012-06-07 |
United States Patent
Application |
20120137778 |
Kind Code |
A1 |
KITAZAWA; So ; et
al. |
June 7, 2012 |
ULTRASONIC INSPECTION EQUIPMENT AND ULTRASONIC INSPECTION
METHOD
Abstract
Ultrasonic inspection equipment facilitates alignment of display
positions of three-dimensional ultrasonic inspection data and
three-dimensional shape data, and quickly discriminates between a
defect echo and an inner-wall echo. A computer 102A has a position
correction function of correcting a relative display position
between three-dimensional shape data and three-dimensional
ultrasonic inspection data. A display position of the
three-dimensional ultrasonic inspection data or that of the
three-dimensional shape data is moved by a norm of a mean vector
along the mean vector that is calculated from a plurality of
vectors defined by a plurality of points selected in the
three-dimensional ultrasonic inspection data and by a plurality of
points selected in the three-dimensional shape data. The
three-dimensional shape data and the three-dimensional ultrasonic
inspection data are displayed in such a manner as to be
superimposed on each other on a three-dimensional display unit
103C.
Inventors: |
KITAZAWA; So; (Mito, JP)
; KONO; Naoyuki; (Mito, JP) ; BABA; Atsushi;
(Tokai, JP) |
Assignee: |
HITACHI, LTD.
Tokyo
JP
|
Family ID: |
40933157 |
Appl. No.: |
13/372003 |
Filed: |
February 13, 2012 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
12472873 |
May 27, 2009 |
|
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|
13372003 |
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Current U.S.
Class: |
73/606 |
Current CPC
Class: |
G01N 29/06 20130101;
G01N 29/04 20130101; G06T 19/20 20130101; G10K 11/00 20130101 |
Class at
Publication: |
73/606 |
International
Class: |
G01N 29/00 20060101
G01N029/00 |
Foreign Application Data
Date |
Code |
Application Number |
May 30, 2008 |
JP |
2008-142192 |
Claims
1. Ultrasonic inspection equipment comprising: an array-probe
ultrasonic sensor including a plurality of piezoelectric vibration
elements; a pulser for supplying each of the piezoelectric
vibration elements of the array-probe ultrasonic sensor with a
transmission signal; a receiver for receiving a signal from each of
the piezoelectric vibration elements of the array-probe ultrasonic
sensor; a delay control unit for setting a delay time for the
transmission signal and a delay time for the received signal
differently for respective piezoelectric vibration elements; a data
storage unit for storing a waveform of an ultrasonic wave received
by the array-probe ultrasonic sensor; a computer for image
processing, the computer generating three-dimensional ultrasonic
inspection data from the waveform recorded by the data storage
unit; a data storage unit for storing three-dimensional shape data;
and a three-dimensional display unit for displaying
three-dimensional shape data and the three-dimensional ultrasonic
inspection data; wherein the computer displays a picture of a
reflection intensity distribution of a plane which is parallel to
two axes of a coordinate system of the three-dimensional ultrasonic
inspection data from the data storage unit in which the waveform of
the ultrasonic wave received by the array-probe ultrasonic sensor
is stored on a cross-section display screen, displays the
three-dimensional inspection data and the three-dimensional shape
data from data storage unit in which three-dimensional shape data
is stored in such a manner as to be superimposed on each other, and
displays a plane which shows a position of a plane of the picture
of the reflection intensity distribution with the three-dimensional
inspection data and the three-dimensional shape data on the screen
of the display unit.
2. An ultrasonic inspection method comprising the steps of:
displaying a picture of a reflection intensity distribution of a
plane which is parallel to two axes of a coordinate system of the
three-dimensional ultrasonic wave received by the array-probe
ultrasonic sensor is stored on a cross-section display screen,
displaying the three-dimensional inspection data and the
three-dimensional shape data from data storage unit in which
three-dimensional shape data is stored in such a manner as to be
superimposed on each other, and displaying a plane which shows a
position of a plane of the picture of the reflection intensity
distribution with the three-dimensional inspection data and the
three-dimensional shape data on the screen of the display unit.
Description
[0001] This application is a continuation of U.S. patent
application Ser. No. 12/472,873, filed May 27, 2009.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to ultrasonic inspection
equipment and method for performing ultrasonic inspection that is a
kind of non-destructive examination, and more particularly to
ultrasonic inspection equipment and method that use an array-probe
ultrasonic sensor.
[0004] 2. Description of the Related Art
[0005] In the field of ultrasonic inspection methods for inspecting
various kinds of structural materials, an inspection method for
imaging an internal state of a target to be inspected in a short
period of time with high accuracy to inspect the target has been
developed in recent years. Such an inspection method for imaging is
typified by a phased array method, a synthetic aperture focusing
technique, and the like (for example, refer to non-patent document
1).
[0006] The phased array method uses a so-called array-probe
ultrasonic sensor having a plurality of piezoelectric vibration
elements arrayed therein. The phased array method is based on the
principles that wavefronts of ultrasonic waves individually
transmitted from the piezoelectric vibration elements interfere
with one another to form a composite wavefront, which then
propagates. Therefore, by delaying the ultrasonic-wave transmission
timing of each of the piezoelectric vibration elements so as to
shift the timing of each ultrasonic wave, an incident angle of each
ultrasonic wave can be controlled, thereby making it possible to
focus the ultrasonic waves.
[0007] In addition, upon reception of ultrasonic waves, a
reflection ultrasonic wave received by each of the piezoelectric
vibration elements is shifted prior to its addition. Thus, as is
the case with the transmission of ultrasonic waves, an incident
angle of the received ultrasonic wave can be controlled. Also it is
possible to receive the focused ultrasonic waves.
[0008] In general, the following methods are known as the phased
array method: the linear scan method in which piezoelectric
vibration elements of a one-dimensional array sensor are
rectilinearly scanned; and the sector scan method in which
transmission and receiving directions of an ultrasonic wave are
changed in sector-like fashion. In addition, if a two-dimensional
array sensor having piezoelectric vibration elements arrayed in a
lattice-shaped pattern is used, ultrasonic waves can be
three-dimensionally focused at any position, thereby providing a
scan method that is suitable for a target to be inspected. Both of
the above-described methods are capable of: scanning an ultrasonic
wave at high speed without moving an array-probe ultrasonic sensor;
and optionally controlling an incident angle of an ultrasonic wave
and a position of the depth of focus without replacing an
array-probe ultrasonic sensor. The linear scan method and the
sector scan method are techniques that enable high-speed,
high-accuracy inspection.
[0009] Next, the principle on which the synthetic aperture focusing
technique is based is as follows. When an ultrasonic wave is
transmitted in such a manner that wave motion of the ultrasonic
wave widely diffuses into a target to be inspected, and a reflected
ultrasonic wave signal of the ultrasonic wave is received, a
position of a defect, which is a sound source of the received
reflected ultrasonic wave, exists along a circular arc whose radius
is the propagation distance of the reflected ultrasonic wave with a
position of a piezoelectric vibration element which has transmitted
and received the ultrasonic wave defined as the center of the
circular arc. Based on the principle, an ultrasonic wave is
transmitted and is received while the piezoelectric vibration
element is successively moved, and each received waveform at
respective positions of the piezoelectric vibration element is
calculated by a computer so as to extend a waveform in the shape of
a circular arc. As a result, intersection points of the circular
arcs are concentrated on the position of a defect that is an
ultrasonic-wave reflection source, thereby making it possible to
identify the position of the defect. How the computer performs the
calculation for the above process is described in the non-patent
document 1.
[0010] With the above-described methods, each of which employs a
sensor in which a plurality of piezoelectric vibration elements are
arrayed, it is possible to three-dimensionally obtain a reflected
ultrasonic wave signal indicative of a defect without movement of
the sensor. However, in order to identify a three-dimensional
reflection position from the reflected ultrasonic wave signal, for
example, the following estimation is required: estimating the
reflection position from a plurality of two-dimensional images of
the reflection intensity distribution, positions of the
two-dimensional images spatially differing from one another; or
estimating the reflection position by converting the reflection
intensity distribution into three-dimensional data, and then by
three-dimensionally displaying the converted data.
[0011] For example, in the case of the linear scan and the sector
scan in the phased array method, a plurality of two-dimensional
reflection intensity images according to known scanning pitch can
be acquired. Accordingly, a direction in which a reflected wave
occurs can be identified by displaying images on a screen while the
images are successively switched. However, there are limits to
apply this method to some three-dimensional scanning other than the
above-described scanning.
[0012] In such a case, reflected ultrasonic wave signals from a
plurality of directions are subjected to interpolation processing
or the like to create three-dimensional lattice-shaped data. The
three-dimensional lattice-shaped data obtained is displayed as an
image using a method such as volume rendering and surface
rendering. There is also a method in which reflected ultrasonic
wave signals are displayed as a three-dimensional point group
without converting the reflected ultrasonic wave signals into
lattice-shaped data. In any case, because the reflected ultrasonic
wave signals are stored as three-dimensional ultrasonic inspection
data, an inspector can check the three-dimensional ultrasonic
inspection data from any direction after measurement (for example,
refer to non-patent document 2).
[0013] However, it is difficult to judge only from the
three-dimensional ultrasonic inspection data whether a peak of the
reflection intensity distribution results from the reflection on an
end face or a boundary surface of a target to be inspected or from
the reflection on a defect. In particular, in the case of a
complicatedly shaped target to be inspected, a large number of
reflected ultrasonic wave signals (inner-wall echoes) resulting
from such a shape are generated. Therefore, it is difficult even
for an expert to discriminate between an inner-wall echo and a
defect echo. However, software is developed that is capable of
displaying three-dimensional shape data of a target to be inspected
together with three-dimensional ultrasonic inspection data.
Superimposing these two pieces of data on each other to make a
comparison between them facilitates the discrimination between an
inner-wall echo and an echo resulting from a defect (defect echo).
Incidentally, data that has been separately created by
general-purpose CAD (Computer Aided Design) is often read and used
as three-dimensional shape data (for example, refer to the
non-patent document 2).
[0014] Cited references are as follows:
Patent document 1: [0015] JP-A-6-102258 Non-patent document 1:
[0016] "Norimasa KONDO, Yoshimasa OHASHI, Akiro SANEMORI, Digital
Signal Processing Series, Vol. 12 .left brkt-top.Digital Signal
Processing in Measurement Sensor.right brkt-bot., PP. 143-186, May
20, 1993, Published by Shokodo Non-patent document 2: [0017] Potts,
A.; McNab, A.; Reilly, D.; Toft, M., "Presentation and analysis
enhancements of the NDT Workbench a software package for ultrasonic
NDT data", REVIEW OF PROGRESS IN QUANTITATIVE NONDESTRUCTIVE
EVALUATION; Volume 19, AIP Conference Proceedings, Volume 509, pp.
741-748 (2000)
SUMMARY OF THE INVENTION
[0018] However, because three-dimensional ultrasonic inspection
data and three-dimensional shape data are usually made in separate
coordinate systems, correction of display positions is always
required to superimpose on each other these pieces of data are.
Further, a theoretical value and an actually measured value of the
sound velocity are used to display the three-dimensional ultrasonic
inspection data. However, because the theoretical value differs
from the actually measured value in a target to be inspected,
correction of display scales is also required. If the correction of
display positions and the correction of display scales are not
correctly performed, correlation of the three-dimensional
ultrasonic inspection data with the three-dimensional shape data
cannot be confirmed. This makes impossible to discriminate between
an inner-wall echo and a defect echo. Heretofore, an inspector
inputs information about the position correction and the sound
velocity correction through a display unit, or directly processes
three-dimensional ultrasonic inspection data and three-dimensional
shape data. The inspector need repeat the correction work until the
discrimination between an inner-wall echo and a defect echo is
attained. It is disadvantageous to take a huge amount of time for
such correction work.
[0019] Incidentally, it is known that two-dimensional ultrasonic
inspection data and two-dimensional shape data are displayed with
these pieces of data superimposed on each other (for example, refer
to lines 34 through 40 on the right column in page 6 of the patent
document 1). The patent document 1 does not describe a specific
technique for superimposing these pieces of data on each other.
However, the patent document 1 describes that the pieces of data
are superimposed on each other by establishing the coincidence
between coordinates of an origin point of the two-dimensional
ultrasonic inspection data and coordinates of an origin point of
the two-dimensional shape data. However, in general, the origin
point of the two-dimensional ultrasonic inspection data often
differs from the origin point of the two-dimensional shape data.
Accordingly, even if the coordinates of the origin point of the
two-dimensional ultrasonic inspection data simply coincide with the
coordinates of the origin point of the two-dimensional shape data,
both of data cannot be successfully superimposed on each other.
Moreover, the patent document 1 relates to the superimposition of
two-dimensional ultrasonic inspection data and two-dimensional
shape data. When the patent application described in the patent
document 1 was filed, there was no technique for acquiring
three-dimensional ultrasonic inspection data. Therefore, the
superimposition of three-dimensional ultrasonic inspection data and
three-dimensional shape data was not known. Differently from the
superimposition of two-dimensional ultrasonic inspection data and
two-dimensional shape data, for the superimposition of
three-dimensional ultrasonic inspection data and three-dimensional
shape data tilts of both data need be taken into consideration.
[0020] An object of the present invention is to provide ultrasonic
inspection equipment and method which facilitate alignment of
display positions of three-dimensional ultrasonic inspection data
and three-dimensional shape data, and which are capable of quickly
discriminating between a defect echo and an inner-wall echo.
[0021] (1) In order to achieve the above-described object,
according to one aspect of the present invention, there is provided
ultrasonic inspection equipment comprising:
[0022] an array-probe ultrasonic sensor including a plurality of
piezoelectric vibration elements;
[0023] a pulser for supplying each of the piezoelectric vibration
elements of the array-probe ultrasonic sensor with a transmission
signal;
[0024] a receiver for receiving a signal from each of the
piezoelectric vibration elements of the array-probe ultrasonic
sensor;
[0025] a delay control unit for setting a delay time for the
transmission signal and a delay time for the received signal
differently for respective piezoelectric vibration elements;
[0026] a data storage unit for storing a waveform of an ultrasonic
wave received by the array-probe ultrasonic sensor;
[0027] a computer for image processing, the computer generating
three-dimensional ultrasonic inspection data from the waveform
recorded by the data storage unit; and
[0028] a three-dimensional display unit for displaying
three-dimensional shape data and the three-dimensional ultrasonic
inspection data;
[0029] wherein the computer includes position correction means for
correcting a relative display position of the three-dimensional
shape data and that of the three-dimensional ultrasonic inspection
data; and
[0030] the position correction means is adapted to move a position
at which the three-dimensional ultrasonic inspection data is
displayed or a position at which the three-dimensional shape data
is displayed by a norm of a mean vector based on the mean vector,
and to then display the three-dimensional shape data and the
three-dimensional ultrasonic inspection data on the
three-dimensional display unit in such a manner as to be
superimposed on each other, wherein the mean vector is calculated
from a plurality of vectors defined by a plurality of points
selected in the three-dimensional ultrasonic inspection data and by
a plurality of points selected in the three-dimensional shape data,
the points selected in the three-dimensional shape data
corresponding to the respective points selected in the
three-dimensional ultrasonic inspection data.
[0031] The above-described configuration facilitates the alignment
of display positions of three-dimensional ultrasonic inspection
data and three-dimensional shape data. This makes it possible to
quickly discriminate between a defect echo and an inner-wall
echo.
[0032] (2) In the above-described item (1), preferably, the
computer includes scale correction means for correcting a relative
display scale between the three-dimensional shape data and the
three-dimensional ultrasonic inspection data; and the scale
correction means corrects a relative display scale between the
three-dimensional ultrasonic inspection data and the
three-dimensional shape data such that an absolute value of the
distance between coordinates of two points selected in the
three-dimensional ultrasonic inspection data coincides with an
absolute value of the distance between coordinates of two points
selected in the three-dimensional shape data.
[0033] (3) In the above-described item (1), preferably, when a
plurality of points are selected from the three-dimensional
ultrasonic inspection data, the position correction means displays
data points existing within a specified range of the
three-dimensional ultrasonic inspection data on the
three-dimensional display unit in order of decreasing absolute
value of the data points.
[0034] (4) In the above-described item (1), preferably, the
computer includes data creation means for creating
three-dimensional shape data such that the three-dimensional shape
data is displayed in such a manner as to be superimposed on the
three-dimensional ultrasonic inspection data.
[0035] (5) In the above-described item (1), preferably, the
computer displays a plane indicating a cross section at an optional
position of the three-dimensional ultrasonic inspection data on the
three-dimensional display unit together with the three-dimensional
ultrasonic inspection data.
[0036] (6) In order to achieve the above-described object,
according to another aspect of the present invention, there is
provided an ultrasonic inspection method comprising the steps
of:
[0037] moving a position at which the three-dimensional ultrasonic
inspection data is displayed or a position at which the
three-dimensional shape data is displayed by a norm of a mean
vector based on the mean vector, and then displaying the
three-dimensional shape data and the three-dimensional ultrasonic
inspection data, wherein the mean vector is calculated from a
plurality of vectors defined by a plurality of points selected in
the three-dimensional ultrasonic inspection data created from a
plurality of ultrasonic wave waveforms received by an array-probe
ultrasonic sensor and by a plurality of points selected in the
three-dimensional shape data, the points selected in the
three-dimensional shape data corresponding to the respective points
selected in the three-dimensional ultrasonic inspection data.
[0038] The above-described method facilitates the alignment of
display positions of three-dimensional ultrasonic inspection data
and three-dimensional shape data. This makes it possible to quickly
discriminate between a defect echo and an inner-wall echo.
[0039] (7) In the above-described item (6), preferably, the
ultrasonic inspection method further comprises the step of
correcting a relative display scale between the three-dimensional
ultrasonic inspection data and the three-dimensional shape data
such that the sum total of absolute values of the distance between
coordinates of two points selected in the three-dimensional
ultrasonic inspection data coincides with the sum total of absolute
values of the distance between coordinates of two points selected
in the three-dimensional shape data, the three-dimensional
ultrasonic inspection data being created from the plurality of
ultrasonic wave waveforms received by the array-probe ultrasonic
sensor.
[0040] According to the present invention, the alignment of display
positions of three-dimensional ultrasonic inspection data and
three-dimensional shape data is facilitated. This makes it possible
to quickly discriminate between a defect echo and an inner-wall
echo.
BRIEF DESCRIPTION OF THE DRAWINGS
[0041] FIG. 1 is a system block diagram illustrating a
configuration of ultrasonic inspection equipment according to one
embodiment of the present invention;
[0042] FIG. 2 is a flowchart illustrating processing executed based
on the position correction method for correcting a position of
three-dimensional ultrasonic inspection data and that of
three-dimensional shape data by the ultrasonic inspection equipment
according to one embodiment of the present invention;
[0043] FIG. 3 is a diagram illustrating the position correction
method for correcting a position of three-dimensional ultrasonic
inspection data and that of three-dimensional shape data by the
ultrasonic inspection equipment according to one embodiment of the
present invention;
[0044] FIG. 4 is a diagram illustrating the position correction
method for correcting a position of three-dimensional ultrasonic
inspection data and that of three-dimensional shape data by the
ultrasonic inspection equipment according to one embodiment of the
present invention;
[0045] FIG. 5 is a flowchart illustrating processing executed based
on the scale correction method for correcting a scale of
three-dimensional ultrasonic inspection data and that of
three-dimensional shape data by the ultrasonic inspection equipment
according to one embodiment of the present invention;
[0046] FIG. 6 is a diagram illustrating the scale correction method
for correcting a scale of three-dimensional ultrasonic inspection
data and that of three-dimensional shape data by the ultrasonic
inspection equipment according to one embodiment of the present
invention;
[0047] FIG. 7 is a flowchart illustrating processing executed based
on the creating method for creating three-dimensional shape data by
the ultrasonic inspection equipment according to one embodiment of
the present invention;
[0048] FIG. 8 is a diagram illustrating the creation method for
creating three-dimensional shape data by the ultrasonic inspection
equipment according to one embodiment of the present invention;
[0049] FIG. 9 is a diagram illustrating the creation method for
creating three-dimensional shape data by the ultrasonic inspection
equipment according to one embodiment of the present invention;
[0050] FIG. 10 is a flowchart illustrating processing executed
based on a distance measuring method for measuring the distance
between optional two points by the ultrasonic inspection equipment
according to one embodiment of the present invention; and
[0051] FIG. 11 is a system block diagram illustrating another
configuration of ultrasonic inspection equipment according to one
embodiment of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0052] A configuration of ultrasonic inspection equipment and
operation thereof according to one embodiment of the present
invention will be described below with reference to FIGS. 1 through
11.
[0053] First of all, a configuration of ultrasonic inspection
equipment according to this embodiment will be described with
reference to FIG. 1.
[0054] FIG. 1 is a system block diagram illustrating the
configuration of the ultrasonic inspection equipment according to
one embodiment of the present invention.
[0055] The ultrasonic inspection equipment according to this
embodiment includes: an array-probe ultrasonic sensor 101 for
emitting an ultrasonic wave toward a target to be inspected 100; a
transmitting/receiving unit 102; and a display unit 103 for
displaying a received signal and an inspection image.
[0056] As described in the figure, the array-probe ultrasonic
sensor 101 is basically constituted of a plurality of piezoelectric
vibration elements 104, each of which generates an ultrasonic wave
and then receives the ultrasonic wave. The array-probe ultrasonic
sensor 101 is disposed on an inspection surface of the target to be
inspected 100. The array-probe ultrasonic sensor 101 then generates
an ultrasonic wave 105 in response to a driving signal supplied
from the transmitting/receiving unit 102 so that the ultrasonic
wave 105 propagates into the target to be inspected 100. As a
result, the array-probe ultrasonic sensor 101 detects a reflected
wave of the ultrasonic wave 105 therefrom, and then inputs a
received signal into the transmitting/receiving unit 102.
[0057] The transmitting/receiving unit 102 transmits and receives
the ultrasonic wave generated by the array-probe ultrasonic sensor
101. The transmitting/receiving unit 102 includes a computer 102A,
a delay-time control unit 102B, a pulser 102C, a receiver 102D, a
data storage unit 102E, a mouse 102F, and a keyboard 102G. The
pulser 102C supplies the array-probe ultrasonic sensor 101 with a
driving signal. Then, when the receiver 102D receives a signal from
the array-probe ultrasonic sensor 101, the receiver 102D handles
the received signal.
[0058] The computer 102A basically includes a CPU 102A1, a RAM
102A2, and ROM 102A3. A program for controlling the CPU 102A1 is
written to the ROM 102A3. According to this program, the CPU 102A1
reads external data required by the data storage unit 102E, or
transmits/receives data to/from the RAM 102A2 while computation is
performed. In addition, the CPU 102A1 outputs handled data to the
data storage unit 102E if necessary.
[0059] Moreover, the CPU 102A1 controls the delay-time control unit
102B, the pulser 102C, and the receiver 102D so that required
operation is achieved. The delay-time control unit 102B controls
both the timing of a driving signal output from the pulser 102C and
the input timing of the received signal received by the receiver
102D. Thus the operation of the array-probe ultrasonic sensor 101
is performed based on the phased array method.
[0060] Here, in the operation of the array-probe ultrasonic sensor
101 based on the phased array method described above, the focal
depth and incident angle 106 of the ultrasonic wave 105 are
controlled so as to transmit an ultrasonic wave and then to receive
the ultrasonic wave. Thus, the received signal is supplied from the
receiver 102D to the data storage unit 102E. Next, the data storage
unit 102E handles the supplied received signal, and then records
the handled data as recorded data, and also transmits the handled
data to the computer 102A. On the receipt of the data, the computer
102A combines waveforms obtained by the piezoelectric vibration
elements in response to the delay time, and then performs
interpolation processing suitable for the waveforms of the
ultrasonic wave on an incident angle basis. The computer 102A then
creates the following data: two-dimensional ultrasonic inspection
data in a pixel format in which a two-dimensional square lattice
which is called a "pixel" is used as a unit; and three-dimensional
ultrasonic inspection data in a voxel format in which a
three-dimensional cubic lattice which is called a "voxel" is used
as a unit. The computer 102A controls to convert these pieces of
data into images to display the images on the display unit 103.
[0061] The display unit 103 includes: a two-dimensional display
screen 103B for displaying two-dimensional ultrasonic inspection
data; a three-dimensional display screen 103C for displaying
three-dimensional ultrasonic inspection data; and a waveform
display screen 103A for displaying waveform signals of the
piezoelectric vibration elements. FIG. 1 illustrates only one
display unit 103. However, the waveform display screen 103A, the
two-dimensional display screen 103B, and the three-dimensional
display screen 103C may also be displayed and shared among a
plurality of display units.
[0062] Three-dimensional ultrasonic inspection data is displayed on
the three-dimensional display screen 103C of the display unit 103.
In this case, the three-dimensional ultrasonic inspection data can
be displayed on an optional display scale through the operation of
the mouse 102F and the keyboard 102G connected to the computer
102A. An inspector is allowed to input the Magnification, which is
used to change the display scale, as a numerical value from the
keyboard 102G into the computer 102A. In addition, display color
and transparency can also be optionally changed through the
operation of the mouse 102F and the keyboard 102G. The display
color can be changed in response to the reflection intensity. In
this case, a plurality of display color patterns are prepared and
so the inspector can select among them on the basis of the use of
the three-dimensional ultrasonic inspection data.
[0063] It is to be noted that the three-dimensional drawing
algorithm as described above is implemented in libraries such as
OpenGL (registered trademark) and DirectX (registered trademark),
and that the OpenGL and the DirectX are industry-standard graphics
application programming interfaces (graphics API) used in graphics
applications. When these graphics APIs are used in a program to
give required information about an object to be displayed, such as
a shape, a viewpoint, and a display position, a three-dimensional
shape can be easily drawn at any position on the display unit with
the color, transparency, and scale optionally selected.
[0064] In addition, concurrently with the three-dimensional
ultrasonic inspection data, three-dimensional shape data indicating
a shape of the target to be inspected 100 is displayed on the
three-dimensional display screen 103C. The three-dimensional shape
data is read from the outside of the computer 102A. Moreover, the
inspector is also allowed to create the three-dimensional shape
data on the three-dimensional display screen 103C by use of the
mouse 102F and the keyboard 102G. How to create the
three-dimensional shape data on the three-dimensional display
screen 103C will be described later in detail with reference to
FIG. 7.
[0065] In particular, when CAD (Computer Aided Design) data of the
target to be inspected 100 is available, the CAD data can be read
and displayed. A CAD data format is a data format that enables CAD
software on the market to input and output data. For example, the
CAD data uses the STL (Stereo Lithography) format that enables most
of CAD software to read and output data. The STL format expressed a
surface of an object as a set of a large number of triangles. A STL
file includes surface normal vectors of these triangles, and
coordinate values of three vertexes of each triangle. By drawing
the plurality of triangles, it is easy to display the
three-dimensional shape data 202 from a file in the STL format
using the graphics APIs.
[0066] Further, a plurality of pieces of three-dimensional shape
data can also be concurrently displayed on the three-dimensional
display screen 103C. Irrespective of the three-dimensional
ultrasonic inspection data, selected three-dimensional shape data
can be displayed at any position on any scale from an optional
viewpoint through the operation of the mouse 102F and the keyboard
102G, both of which are connected to the computer 102A.
[0067] In addition, the inspector can also optionally change each
of the display color and the transparency irrespective of the
three-dimensional ultrasonic inspection data through the operation
of the mouse 102F and the keyboard 102G. As a result, even if the
three-dimensional shape data and the three-dimensional ultrasonic
inspection data overlap one another, these pieces of data can be
displayed in such a manner that the inspector can view them easily.
Moreover, show/hide of the three-dimensional shape data can be
switched if necessary.
[0068] Usually, because a coordinate system of three-dimensional
ultrasonic inspection data differs from that of three-dimensional
shape data, both of them are displayed at totally different
positions in an initial state in which these pieces of data are
superimposed upon each other. Even if initial information including
an incident position of a ultrasonic wave is provided, there is,
for example, a small difference in sound velocity inside the target
to be inspected between an actually measured value and a
theoretical value. Therefore, it is necessary to correct a display
position and a display scale.
[0069] As described above, the three-dimensional ultrasonic
inspection data and the three-dimensional shape data can be
displayed independently of each other at any positions on any
scales. The inspector, therefore, can also make alignments by trial
and error so that the three-dimensional ultrasonic inspection data
and the three-dimensional shape data are displayed at desired
relative positions on desired scales. However, because the above
correction work requires much time and effort, the use of a
position correction function and a scale correction function makes
the correction work becomes much easier, which will be described
below.
[0070] Next, a position correction method for correcting a position
of three-dimensional ultrasonic inspection data and that of
three-dimensional shape data by ultrasonic inspection equipment
according to this embodiment will be described with reference to
FIGS. 2 through 4.
[0071] FIG. 2 is a flowchart illustrating processing executed based
on the position correction method for correcting a position of
three-dimensional ultrasonic inspection data and that of
three-dimensional shape data by ultrasonic inspection equipment
according to one embodiment of the present invention. FIGS. 3 and 4
are diagrams each illustrating the position correction method for
correcting a position of three-dimensional ultrasonic inspection
data and that of three-dimensional shape data by ultrasonic
inspection equipment according to one embodiment of the present
invention.
[0072] The position correction method is a function of making a
correction such that three-dimensional ultrasonic inspection data
coincide with three-dimensional shape data at a desired
position.
[0073] In a step S1 shown in FIG. 2, an inspector specifies a
reference point. For example, as shown in FIG. 3, if the inspector
wants to move three-dimensional ultrasonic inspection data 201 in
parallel so that coordinates of an optional point 201A in the
three-dimensional ultrasonic inspection data 201 coincide with
coordinates of an optional point 202A in three-dimensional shape
data 202, the inspector first selects the reference point 201A and
the reference point 202A with the mouse 102F while viewing the
three-dimensional display screen 103C.
[0074] How to select these points on the three-dimensional display
screen 103C will be described as below. First, a position to be
specified as a first reference point in the three-dimensional
ultrasonic inspection data 201 is clicked with the mouse 102F on
the three-dimensional display screen 103C; and the clicked point is
then diagonally dragged with the mouse 102F, so that a rectangle
area is selected. Points included in the three-dimensional
ultrasonic inspection data 201, which are drawn in the rectangular
area, are read into the RAM 102A2 of the computer. Each of the
points has an identification number. Incidentally, identification
numbers are given to data points in order of decreasing absolute
value of data point (in descending order of intensity) among pieces
of ultrasonic inspection data included in the rectangular area.
[0075] In a step S2 shown in FIG. 2, when points included in a
minute area in plural, the CPU 102A1 displays a first point
included in these points on the three-dimensional display screen
103C as a candidate point.
[0076] In a step S3, the inspector specifies the candidate point
through the operation of the mouse 102F or the keyboard 102G.
However, when the candidate point is not a desired data point, the
process returns to the step S2 where the next candidate point is
displayed in order of identification numbers on the screen with the
color thereof successively changed.
[0077] In a step S4, when the desired data point is displayed as a
candidate, the inspector accepts the selection of this point
through the operation of the mouse 102F or the keyboard 102G.
[0078] Next, in a step S5 shown in FIG. 2, a judgment is made as to
whether or not there is another reference point. Here, because it
is also necessary to select the first reference point included in
the three-dimensional shape data 202, the processing in the steps
S1 through S4 is performed to select the first reference point 202A
included in the three-dimensional shape data 202 corresponding to
the first reference point 201A included in the ultrasonic
inspection data 201 shown in FIG. 3, and then to accept the
selection of the first reference point 202A. For example, if the
three-dimensional shape data 202 is STL format data, a point to be
selected is any one of vertexes of a triangle forming the
three-dimensional shape data 202. Algorithm for reading an
identification number of a selected point and positional
information about the selected point into the RAM 102A2 is already
implemented by graphics API such as OpenGL. Accordingly, the use of
functions provided in the graphics API makes it possible to easily
implement the algorithm.
[0079] Further, according to this embodiment, at least two
reference points are used in each of the ultrasonic inspection data
201 and the three-dimensional shape data 202. Therefore, the second
reference point 202B included in the three-dimensional shape data
202 corresponding to the second reference point 201B included in
the ultrasonic inspection data 201 is selected, and the selection
of the second reference point 202B is then accepted.
[0080] Here, the reference points to be selected are, for example,
an ultrasonic wave incident point 201B in the three-dimensional
ultrasonic inspection data 201 and a sensor mounting point
(ultrasonic wave incident position) 202B in the three-dimensional
shape data 202. In another case, the reference points to be
selected are, for example, a peak point of an inner-wall echo whose
cause is known (for example, the point 201A) and points surrounding
the peak point in the three-dimensional ultrasonic inspection data
201, and a point on an end face of the three-dimensional shape data
202 (for example, the point 202A). Besides, for example, the
following reference points shown in FIG. 3 can also be used as
reference points: the reference point 2010 and the reference point
201D included in the three-dimensional ultrasonic inspection data
201; and the reference point 202C and the reference point 202D
included in the three-dimensional shape data 202. With the increase
in the numbers of reference points, the degree of coincidence
between the three-dimensional ultrasonic inspection data and the
three-dimensional shape data can be increased.
[0081] Combinations of corresponding reference points are
automatically set as follows: the reference point 201A and the
reference point 202A; the reference point 201B and the reference
point 202B; the reference point 201C and the reference point 202C;
and the reference point 201D and the reference point 202D. In this
case, a selected reference point is displayed on the
three-dimensional display screen 103C with the color of the
selected reference point changed.
[0082] Next, in a step S6 shown in FIG. 2, the CPU 102A1 calculates
a motion vector of the three-dimensional ultrasonic inspection data
from the plurality of reference points. Here, on the assumptions
that the number of combinations of a point in the three-dimensional
ultrasonic inspection data 201 and its corresponding point in the
three-dimensional shape data 202 is N, and that in the i-th
combination, coordinates of a point and those of its corresponding
point are (xi1, Yi1, zi1) and (xi2, Yi2, zi2) respectively, the
motion vector is an average of motion vectors determined based on
the combinations. The motion vector is calculated by the following
equation (1):
V = ( i = 1 N Xi 2 - Xi 1 N , i = 1 N Yi 2 - Yi 1 N , i = 1 N Zi 2
- Zi 1 N ) Eq . 1 ##EQU00001##
[0083] Next, in a step S7, the CPU 102A1 controls to perform
parallel and rotational movement of the three-dimensional
ultrasonic inspection data 201 by the motion vector based on the
equation (1). The CPU 102A1 then redraws the three-dimensional
ultrasonic, inspection data 201 at a move-to-position as shown in
FIG. 4. Incidentally, the three-dimensional shape data 202 may also
be moved.
[0084] Next, a scale correction method for correcting a scale of
three-dimensional ultrasonic inspection data and that of
three-dimensional shape data by the ultrasonic inspection equipment
according to this embodiment will be described with reference to
FIGS. 5 and 6.
[0085] FIG. 5 is a flowchart illustrating processing executed based
on the scale correction method for correcting a scale of
three-dimensional ultrasonic inspection data and that of
three-dimensional shape data by the ultrasonic inspection equipment
according to one embodiment of the present invention. FIG. 6 is a
diagram illustrating the scale correction method for correcting a
scale of three-dimensional ultrasonic inspection data and that of
three-dimensional shape data by the ultrasonic inspection equipment
according to one embodiment of the present invention.
[0086] When the degree of coincidence between the three-dimensional
ultrasonic inspection data 201 and the three-dimensional shape data
202 is not sufficiently increased only if the position correction
function described with reference to FIGS. 2 through 4 is
performed, a scale correction function is used.
[0087] What will be described next is a case where, for example, as
shown in FIG. 6, the inspector wants to change a display scale of
the three-dimensional ultrasonic inspection data 201 in such a
manner that the distance between the reference point 201B and the
reference point 201D included in the three-dimensional ultrasonic
inspection data 201 coincides with the distance between the
corresponding reference point 202B and the corresponding reference
point 202D included in the three-dimensional shape data 202.
[0088] Processing in steps Sli through S15 shown in FIG. 5 is the
same as that in the steps S1 through S5 shown in FIG. 2.
[0089] Accordingly, in the steps S11 through S15 shown in FIG. 5,
the inspector makes selections on the three-dimensional display
screen 103C with the mouse 102F in the following order: first
selecting two points included in the three-dimensional ultrasonic
inspection data 201; and then selecting two points included in the
three-dimensional shape data 202.
[0090] Incidentally, selections may be made in any order in each of
the three-dimensional ultrasonic inspection data 201 and the
three-dimensional shape data 202. In this case, a selected
reference point is displayed on the three-dimensional display
screen 103C with the color of the selected reference point changed.
Here, the reference points to be selected are, for example, an
ultrasonic wave incident point 201B in the three-dimensional
ultrasonic inspection data 201 and a sensor mounting point 202B in
the three-dimensional shape data 202. In another case, the
reference points to be selected are, for example, a peak point of
an inner-wall echo whose cause is known (for example, the point
201D) and points surrounding the peak point in the
three-dimensional ultrasonic inspection data 201, and a point on an
end face of the three-dimensional shape data 202 (for example, the
point 202D).
[0091] Next, in a step S16, the CPU 102A1 calculates the
magnification of the three-dimensional ultrasonic inspection data
from these reference points. For example, on the assumption that
coordinates of the point 201B, the point 201D are (X1B, Y1B, Z1B),
(X1D, Y1D, Z1D) respectively, whereas coordinates of the point
202B, the point 202D are (X2B, Y2B, Z2B), (X2D, Y2D, Z2D)
respectively, the magnification is calculated by the following
equation (2):
S = ( X 2 D - X 2 B ) 2 + ( Y 2 D - Y 2 B ) 2 + ( Z 2 D - Z 2 B ) 2
( X 1 D - X 1 B ) 2 + ( Y 1 D - Y 1 B ) 2 + ( Z 1 D - Z 1 B ) 2 Eq
. 2 ##EQU00002##
[0092] Next, in a step S17, the CPU 102A1 redraws the
three-dimensional ultrasonic inspection data 201 on a scale that
has been corrected by the magnification calculated by use of the
equation (2). Incidentally, in contrast with the above, the
three-dimensional shape data 202 may also be corrected by a
reduction ratio that is an inverse number of the magnification
calculated by use of the equation (2), before the three-dimensional
shape data 202 is redrawn.
[0093] Next, a creation method for creating three-dimensional shape
data by the ultrasonic inspection equipment according to this
embodiment will be described with reference to FIGS. 7 through
9.
[0094] FIG. 7 is a flowchart illustrating processing executed based
on the creating Method for creating three-dimensional shape data by
the ultrasonic inspection equipment according to one embodiment of
the present invention. FIGS. 8 and 9 are diagrams each illustrating
the creation method for creating three-dimensional shape data by
the ultrasonic inspection equipment according to one embodiment of
the present invention.
[0095] As described above, the three-dimensional shape data 202 is
not necessarily read from the outside of the computer 102A. The
inspector is also allowed to create the three-dimensional shape
data 202 on the computer 102A through the operation of the mouse
102F and the keyboard 102G while viewing the three-dimensional
display screen 103C.
[0096] In a step S21 shown in FIG. 7, the inspector selects a basic
shape which the inspector wants to display on an operation screen.
The basic shape is, for example, a plane, a cube, a cuboid, a
sphere, a cone, or a cylinder.
[0097] Next, in a step S22, the inspector inputs a scale of the
basic shape. An optional numerical value can be inputted as the
scale.
[0098] In a step S23, the CPU 102A1 draws the selected basic shape
at an initial position on the three-dimensional display screen
103C. It is to be noted that the initial position may be set at any
position.
[0099] After the selected basic shape is drawn, the position and
scale of the basic shape relative to those of the three-dimensional
ultrasonic inspection data 201 are aligned to a desired state by
using the position correction function and the scale correction
function. By repeating the above operation for a plurality of basic
shapes, an external shape of the target to be inspected 100 can be
roughly formed. As a matter of course, only representative portions
of the target to be inspected (for example, an inspection surface,
a bottom surface, and a side surface) may be drawn.
[0100] Incidentally, because graphics API such as OpenGL has a
function of drawing shapes including a plane, a cube, a cuboid, a
sphere, a cone, and a cylinder, these shapes can be easily drawn by
use of the graphics API.
[0101] Here, as shown in FIG. 8, the three-dimensional display
screen 103C has a cross-section display screen 304 for displaying
the reflection intensity distribution of planes (for example, a X-Y
plane, a Y-Z plane, and a Z-X plane), each of which is parallel to
two axes of a coordinate system of the three-dimensional ultrasonic
inspection data 201. The cross-section display screen 304 includes
a screen 301A, a screen 302A, and a screen 303A, which display the
reflection intensity distribution of the X-Y plane, the Y-Z plane,
and the Z-X plane respectively. For example, in screen 303A, the
portion of the three-dimensional shape data 307 in the X-Y plane is
shown. Further, as shown in FIG. 9, planes 301B, 302B, and 303B,
which indicate positions of the above-described planes, are
displayed on the three-dimensional display screen 103C together
with the three-dimensional ultrasonic inspection data 201 and the
three-dimensional shape data 202. This enables the inspector to
easily check which portion of a cross section is displayed.
[0102] In addition, because a plane indicating a cross section at
an optional position of the three-dimensional ultrasonic inspection
data is displayed on a three-dimensional display unit together with
the three-dimensional ultrasonic inspection data, the inspector can
efficiently compare the three-dimensional ultrasonic inspection
data with the three-dimensional shape data so as to discriminate
between an inner-wall echo and a defect echo. This makes it
possible to easily and quickly identify a position of a defect of a
target to be inspected.
[0103] For example, when the three-dimensional ultrasonic
inspection data is voxel format data, the three-dimensional
ultrasonic inspection data has a data structure that is equally
spaced along X, Y, Z axes. Therefore, by specifying a value of X on
a voxel basis, the reflection intensity distribution of a Y-Z plane
corresponding to X (that is to say, the distribution of voxel
values) can be easily determined. Similarly, the reflection
intensity distribution of a Z-X plane, and that of a X-Y plane, can
be easily determined by specifying a value of Y and Z respectively.
As shown in FIG. 9, the planes 301B, 302B, 303B can be easily
displayed by using a plane display function of graphics API such as
OpenGL.
[0104] Next, a distance measuring method for measuring the distance
between optional two points by the ultrasonic inspection equipment
according to this embodiment will be described with reference to
FIG. 10.
[0105] FIG. 10 is a flowchart illustrating processing executed
based on the distance measuring method for measuring the distance
between optional two points by the ultrasonic inspection equipment
according to one embodiment of the present invention.
[0106] Referring to FIG. 8, when the inspector specifies two
optional points (for example, points 305A and 305B) with the mouse
102F connected to the computer 102A on the cross-section display
screen 304, the distance 306 between the two points is displayed
at, for example, a position 306 in proximity to a specified point
on the cross-section display screen 304. A method of specifying the
points 305A and 305B is similar to that for specifying a point
included in the three-dimensional ultrasonic inspection data and
the three-dimensional shape data by use of the above-described
graphics API such as OpenGL.
[0107] In a step S31 shown in FIG. 10, the inspector clicks a point
305A on the screen 301A with the mouse 102F.
[0108] Then, in a step S32, the CPU 102A1 selects a point whose
coordinates are closest to those of the clicked point from among
pixels included in a minute area having a specified area, the
minute area including the clicked point. The CPU 102A1 then reads
the coordinates of the selected point into the RAM 102A2 of the
computer.
[0109] Similarly, in steps S33 and S34, the CPU 102A1 selects a
point 305B, and then reads coordinates thereof into the RAM
102A2.
[0110] Next, in a step S35, the CPU 102A1 calculates the distance
between the two selected points from the coordinates of the two
selected points. In a step S36, the CPU 102A1 then displays the
distance on a screen.
[0111] It is to be noted that the above processing is the same as
that for the screen 302A or the screen 303A shown in FIG. 8.
[0112] Next, another configuration of the ultrasonic inspection
equipment according to this embodiment will be described with
reference to FIG. 11.
[0113] FIG. 11 is a system block diagram illustrating another
configuration of the ultrasonic inspection equipment according to
one embodiment of the present invention.
[0114] The example shown in FIG. 1 shows a case where
three-dimensional ultrasonic inspection data is obtained by a
phased array method. The present invention, however, can also be
applied to three-dimensional ultrasonic inspection data obtained by
a method other than the phased array method (for example, a
synthetic aperture focusing technique).
[0115] FIG. 11 is a diagram illustrating a configuration of
ultrasonic inspection equipment based on the synthetic aperture
focusing technique.
[0116] The ultrasonic inspection equipment according to this
example includes: an array-probe ultrasonic sensor 101 for emitting
an ultrasonic wave toward a target to be inspected 100; a
transmitting/receiving unit 102; and a display unit 103 for
displaying a received signal and an inspection image.
[0117] As described in the figure, the array-probe ultrasonic
sensor 101 is basically constituted of a plurality of piezoelectric
vibration elements 104, each of which generates an ultrasonic wave
and then receives the ultrasonic wave. The array-probe ultrasonic
sensor 101 is disposed on an inspection surface of the target to be
inspected 100. The array-probe ultrasonic sensor 101 then generates
an ultrasonic wave 105B in response to a driving signal supplied
from the transmitting/receiving unit 102 so that the ultrasonic
wave 105 propagates into the target to be inspected 100. As a
result, the array-probe ultrasonic sensor 101 detects a reflected
wave of the ultrasonic wave 105 therefrom, and then inputs a
received signal into the transmitting/receiving unit 102.
[0118] Each of the piezoelectric vibration elements 104 of the
array-probe ultrasonic sensor 101 is successively driven by a
driving signal in the required timing to generate an ultrasonic
wave. The driving signal is transmitted from a driving signal
control unit through a pulser. Each of the piezoelectric vibration
elements 104 then receives a reflected wave of the generated
ultrasonic wave in a two-dimensional manner. The received signal is
inputted into the receiver 102D of the transmitting/receiving unit
102.
[0119] In other words, the piezoelectric vibration elements 104 of
the array-probe ultrasonic sensor 101 receive reflected waves of
the ultrasonic waves generated by the piezoelectric vibration
elements 104 respectively. The number of the reflected waves is
equivalent to the total number of the piezoelectric vibration
elements 104.
[0120] The signal inputted into the receiver 102D is successively
recorded in the data storage unit 102E as recorded data. The
computer 102A uses the recorded data to handle a waveform obtained
by each of the piezoelectric vibration elements 104 such that the
waveform is subjected to three-dimensional image processing based
on the synthetic aperture focusing technique before the waveform is
displayed on the display unit 103.
[0121] The computer 102A basically includes a CPU 102A1, a RAM
102A2, and ROM 102A3. A program for controlling the CPU 102A1 is
written to the ROM 102A3. According to this program, the CPU 102A1
reads external data required by the data storage unit 102E, or
transmits/receives data to/from the RAM 102A2 while computation is
performed. In addition, the CPU 102A1 outputs handled data to the
data storage unit 102E if necessary.
[0122] How to display the three-dimensional ultrasonic inspection
data 201, which has been generated based on the synthetic aperture
focusing technique by the computer 102A, together with the
three-dimensional shape data 202 so as to handle the
three-dimensional ultrasonic inspection data 201 is similar to the
method described with reference to FIGS. 2 through 10.
[0123] As described above, according to this embodiment, the
ultrasonic inspection equipment has the position correction
function of correcting a relative display position of
three-dimensional shape data and that of three-dimensional
ultrasonic inspection data. Thus the inspector can efficiently
compare the three-dimensional ultrasonic inspection data with the
three-dimensional shape data so as to discriminate between an
inner-wall echo and a defect echo, thereby making it possible to
easily and quickly identify a position of a defect of a target to
be inspected.
[0124] In addition, the ultrasonic inspection equipment has the
scale correction function of correcting a relative display scale
between three-dimensional shape data and three-dimensional
ultrasonic inspection data. As a result, the inspector can
efficiently compare the three-dimensional ultrasonic inspection
data with the three-dimensional shape data so as to discriminate
between an inner-wall echo and a defect echo, thereby making it
possible to easily and quickly identify a position of a defect of a
target to be inspected.
[0125] Moreover, because data points included in three-dimensional
ultrasonic inspection data, which exist within a specified range,
are displayed on the three-dimensional display unit in order of
decreasing absolute value of data points, coordinates can be more
easily specified to make corrections. The inspector, therefore, can
efficiently compare the three-dimensional ultrasonic inspection
data with the three-dimensional shape data so as to discriminate
between an inner-wall echo and a defect echo, thereby making it
possible to easily and quickly identify a position of a defect of a
target to be inspected.
[0126] Further, because the ultrasonic inspection equipment has
data creation means for creating three-dimensional shape data, the
inspector can efficiently compare the three-dimensional ultrasonic
inspection data with the three-dimensional shape data so as to
discriminate between an inner-wall echo and a defect echo, thereby
making it possible to easily and quickly identify a position of a
defect of a target to be inspected.
[0127] Furthermore, because a plane indicating a cross section at
an optional position of the three-dimensional ultrasonic inspection
data is displayed on the three-dimensional display unit together
with the three-dimensional ultrasonic inspection data, the
inspector can efficiently compare the three-dimensional ultrasonic
inspection data with the three-dimensional shape data so as to
discriminate between an inner-wall echo and a defect echo, thereby
making it possible to easily and quickly identify a position of a
defect of a target to be inspected.
* * * * *