JPH116820A - Method for ultrasonic probe imaging - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for ultrasonic probe imaging capable of obtaining data of a surface echo and an inner flaw echo by one time of measuring, of reducing number of times of measuring and amount of data to be managed, of concurrently indicating at least two images and of improving clearness of the images. SOLUTION: An ultrasonic wave 18 is emitted to a body to be inspected 13 by pulses and the ultrasonic wave reflected by the body is received, then an echo signal is detected from the received signal by a gate. The echo signal is converted to image data. The measured image is indicated on a display device 25 by using the image data obtained at each of the measuring points. The gate consists of at least two independent gate units. One of the gate units detects a surface echo signal and the other detects an inner flaw echo signal. The image of an outer shape based on the surface echo signal and the image of an inner flaw shape based on the inner flaw echo signal are indicated on the display device 25 by indicating the relative position relationship of both of the shapes.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic exploration imaging method, and more particularly, to an ultrasonic exploration method which simultaneously captures an echo from the surface of an object and an echo from the inside to form an image and simultaneously displays the surface shape and the internal defect shape. Related to video method.

[0002]

2. Description of the Related Art In a conventional ultrasonic exploration imaging method, a focused ultrasonic wave is applied from an ultrasonic probe including an acoustic lens to a subject in water, and defects on the surface and inside of the subject are detected. The ultrasonic wave reflected by the ultrasonic probe returns to the ultrasonic probe and is detected as an echo, sent to a receiver as a voltage signal, the voltage signal is amplified by this receiver, and imaged by a gate circuit at the next stage detector Part of the information is taken out as a DC signal (peak value) as an echo signal. The ultrasonic probe is 3
It is moved along the measurement surface of the subject by the three-dimensional scanner,
The measurement is performed at specified measurement intervals, and the DC voltage at each measurement point is obtained. These DC voltage values are A / D
The converted measurement data is stored in the memory address of the image processing device in association with the measurement point and the XY position of each display dot on the display, so that the search video is displayed on the display in real time.

As a document of the conventional apparatus, Japanese Utility Model Laid-Open No. 5-4009
No. Gazette. This document discloses an ultrasonic flaw detector having a surface gate circuit and a central gate circuit.

[0004]

In the conventional general ultrasonic imaging method, the gate set by the gate circuit is one.
Therefore, only one of an echo signal from the surface of the subject and an echo signal from an internal defect could be detected.

By the way, when a certain causal relationship between the surface shape and the state of the subject and the shape and the state of the internal defect thereof is suspected in the measurement by the ultrasonic survey imaging method, the suspicion is clarified. Measurements need to be made. In such a measurement, since the conventional ultrasonic survey imaging method is a one-gate method, first measure the surface echo,
Next, a method has been adopted in which the defect echo is measured by changing the setting, and two images obtained from each measurement are compared and evaluated. For this reason, the measurement must be performed twice, which is troublesome, the data to be managed is doubled, and handling of data processing and image display is inconvenient.

[0006] The ultrasonic flaw detector disclosed in the above document has a configuration provided with two gate circuits. However, this configuration aims to perform flaw detection with less erroneous determination even when the thickness of the test piece changes, and to perform inspection as wide as possible in the plate thickness direction. There is no disclosure or suggestion of the technical matter of displaying different images simultaneously.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems. The data of the surface echo and the internal defect echo can be obtained by one measurement, and the number of measurements and the data to be managed can be reduced. It is an object of the present invention to provide an ultrasonic exploration image method capable of simultaneously displaying two images and improving visibility.

[0008]

According to the first aspect of the present invention, there is provided an ultrasonic exploration imaging method (corresponding to claim 1) for pulsating an ultrasonic wave with respect to a subject to achieve the above object. Irradiates, receives the ultrasonic wave reflected back from the subject, detects the echo signal from the received signal by the gate, converts this echo signal into video data, and obtains the video data obtained at each measurement point. A method of displaying a measurement image on a display device by using the above-mentioned method. Further, the above-mentioned gate is composed of at least two independent gates, one gate detects a surface echo signal, and the other gate detects an internal defect echo signal. A method of detecting and displaying, on the display device, an image of the surface shape based on the surface echo signal and an image of the internal defect shape based on the internal defect echo signal so that the relative positional relationship between the two shapes is clearly displayed. is there

In the above ultrasonic exploration imaging method, since at least two gates are provided, the image data of the surface echo and the image data of the internal defect echo can be obtained by one measurement. Data to be managed can be reduced. On the screen of the display device, the image of the surface shape and the image of the internal defect shape are displayed in one image so that the positional relationship is clear, and it is possible to obtain good information that is easy to see and judge as measurement information. It is.

According to a second aspect of the present invention, there is provided the ultrasonic exploration imaging method according to the first aspect, wherein the image of the surface shape based on the surface echo signal and the internal defect echo signal are preferably used. The image of the internal defect shape based on the image is synthesized and displayed in a superimposed manner. Since they are displayed in a superimposed state, the positional relationship can be clearly understood.

A third aspect of the present invention is directed to the ultrasonic exploration imaging method according to the first aspect, wherein the image of the surface shape based on the surface echo signal and the internal defect echo signal are preferably obtained. A different color is applied to each of the images of the internal defect shape based on the image. According to this method, each image can be distinguished by color, and the positional relationship can be clearly identified.

According to a fourth aspect of the present invention, there is provided an ultrasonic exploration imaging method according to the first to third aspects, wherein another internal defect echo signal is detected instead of the surface echo signal in the first to third methods. Another feature is that an image of the internal defect shape based on the internal defect echo signal and an image of the internal defect shape based on the internal defect echo signal described above are displayed. One of the images detected by the plurality of gates does not need to be an image related to the surface shape, and may be an image of a plurality of internal defects.

[0013]

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

FIG. 1 shows an outline of the overall configuration of the ultrasonic survey imaging apparatus. A subject 13 is arranged on a pedestal 12 on a sample stage 11. The subject 13 is usually placed in water, which is an ultrasonic wave propagation medium. A triaxial scanner 15 is provided on a support 14 provided on the sample stage 11, and an ultrasonic probe 16 is attached to a tip of the triaxial scanner 15. The three-axis scanner 15 can move the ultrasonic probe 16 in each of the X, Y, and Z axis directions. The ultrasonic probe 16 includes an acoustic lens, and is installed such that the tip thereof faces the surface of the subject 13. The ultrasonic probe 16 is scanned and moved by the three-axis scanner 15.

The transmitter 17 applies an oscillating voltage signal to the piezoelectric element included in the ultrasonic probe 16 in a pulsed manner. The ultrasonic probe 16 generates an ultrasonic wave 18 based on the voltage signal and irradiates the ultrasonic wave to the subject 13. The irradiated ultrasonic wave is reflected on the surface or an internal defect of the subject 13 and returns to the ultrasonic probe 16 as a reflected wave (ultrasonic echo). The ultrasonic probe 16 converts the echo into a voltage signal and sends it to the receiver 19. The receiver 19 amplifies the input voltage signal and outputs the amplified voltage signal to the next-stage two-gate ultrasonic flaw detector 20.

The two-gate ultrasonic flaw detector 20 has a function as a detector that extracts two types of echo signals using two gates. In this example, the two gates are independent. The first gate is set to detect an echo signal related to an ultrasonic echo from the surface of the subject 13, and the second gate is set to detect an echo signal related to an ultrasonic echo from a defect inside the subject 13. I have. 2
Data (measurement data) relating to the echo signal extracted by the gate type ultrasonic flaw detector 20 is output to the oscilloscope 21 and the control device 22. The oscilloscope 21 is used for observing an ultrasonic waveform. The control device 22 controls the entire device, and inputs measurement data obtained via the two-gate ultrasonic flaw detector 20, and the image processing device 23
Output to The driving device 24 is a device that operates a motor of each axis built in the three-axis scanner 15. The image processing device 23 visualizes the measurement site based on the measurement data provided from the control device 22. Specifically, video data is created by storing the measurement points and the XY positions of the respective display dots on the display in a memory address of the image processing apparatus in association with each other. The display 25 displays an image of the measurement site based on the image data created by the image processing device 23.

In the ultrasonic inspection and imaging apparatus having the above configuration, the ultrasonic flaw detector 20 is of a two-gate type, so that each gate detects an echo signal from the surface of the subject 13 and an echo signal from its internal defect. At the same time, image data is created from the echo signals obtained at each gate, and image display is performed on the screen of the display 25 so that the relative positional relationship between the two images, that is, the image of the surface and the image of the internal defect, becomes clear. It was configured to perform.

Next, a method for displaying two images will be described with reference to FIGS. FIG. 2 shows the relationship between the subject 13 and the ultrasound probe 16 and shows the state of the outer surface and the cross section B of the subject 13 as viewed from the arrow A. This subject 13
Then, a disk-shaped convex portion 13a (shown on the outer surface A) is provided on the surface thereof.
It is assumed that there is a triangular defect 13b (shown in the cross section B) inside the defect 13b. Reference numeral 18 denotes a pulsed focused ultrasonic wave provided from the ultrasonic probe 16 to the subject 13.

The subject 13 having the above-mentioned shape is irradiated with the ultrasonic waves 18 to obtain echoes thereof. In this case, FIG. 3 shows an example (A) and (B) of the one-gate method and an example (C) of the two-gate method. In FIG. 3A, the gate 31 is set corresponding to the signal 32 of the surface echo,
This shows a state where only a surface echo is detected. FIG. 3B shows a state in which the gate 33 is set in correspondence with the signal 34 of the defect echo of the section B, and detects only the defect echo. On the other hand, FIG. 3C shows a two-gate system, in which a gate 31 corresponding to a surface echo signal 32 and a gate 33 corresponding to a defect echo signal 34 in section B are set. 34 are detected. Signal 3
For 4, the threshold is set.

When an image is created by each of the detections shown in FIGS. 3A to 3C, the result is as shown in FIG. FIG. 4A corresponds to FIG. 3A, and is an image in which image data is created based on the surface echo signal 32 and displayed on the display 25. FIG. 4B corresponds to FIG. 3B, and is an image in which image data is created based on the signal 34 of the defect echo of the section B and displayed on the display 25. FIG. 4C is FIG.
2C, two images based on the image data based on the surface echo signal 32 and the image data based on the defect echo signal 34 of the section B are combined and displayed on the display 25. According to the composite image in FIG. 4C, the relative positional relationship between the two images is clear. Further, in this video, a process is performed in the image processing device 23 so as to show only the combined outline of the two shapes.

In the above embodiment, the two gates 31 independently set by the two-gate ultrasonic flaw detector 20,
32, an echo signal related to the shape of the surface of the subject 13 and an echo signal related to the shape of a defect in the section B inside the object 13 are detected, image data is created from each signal, and the two images are processed by image processing. It is composed and displayed. The number of gates is not limited to two, and may be three or more. When each image is created from the obtained image data of a plurality of shapes and these images are combined and displayed on the screen of the display 25, various methods can be used for the combination.

The technically important point is that, when applying the ultrasonic probe imaging method to the subject, the ultrasonic probe image method is applied to the image data of the surface of the subject and at least one image inside the subject. A plurality of gates can be set so that video data of a defect at a location can be set, and a plurality of videos created based on the plurality of video data are determined so that their relative positional relations can be clarified. Is configured to be displayed on one display screen. As a method of visualizing the relative positional relationship, it is preferable to display the same location in an overlapping manner.

With this configuration, the number of measurements can be reduced,
The amount of measurement data to be managed can be reduced. Further, the positional relationship between the surface shape of the subject and the internal defect shape can be clearly displayed. The surface shape and internal defect shape are 1
A clear image can be obtained as compared with the conventional transmission method that can be displayed on one measurement image by measuring the degree.

Next, an embodiment in which two or more gates are set to detect and image a plurality of defects existing inside the subject by referring to FIGS. 5 to 8 will be described. FIG. 5 shows an example of the subject, and the subject 41 has a multilayer structure. An example of the subject 41 is a new material CFRP. In the subject 41, it is assumed that defects are scattered in each of the layers 41a to 41e. 6A to 6E show respective layers 41a to 41e.
Indicates a defect. Therefore, in the case of the present embodiment, as shown in FIG. 7, the signals 42a to 42 of the reflected echoes from each layer.
e, five gates 43a-43e are set corresponding to each of e. The signal 42f is a signal related to the echo reflected from the surface of the subject. Using these gates, reflected echoes due to defects from each layer are simultaneously detected. An image related to each defect is created by using a signal based on a reflected echo from a defect in each layer detected at the same time, and is simultaneously displayed on a display screen. At this time, since the image of the defect of each layer shown in FIG. 6 is displayed in a superimposed manner, each layer is displayed in different colors for easy understanding. FIG. 8 shows a state of color classification by a convenience letter and a pattern. In this case, when a defect exists in two or more layers,
Either only the defect data of the layer closer to the surface is validated and displayed, or the display color for the overlapping defect is determined separately and displayed in that color.

[0025]

As is apparent from the above description, according to the present invention, in the ultrasonic exploration imaging method, by setting a plurality of gates, the image data of the surface of the subject and the plurality of internal data can be obtained by one measurement. Since the image data relating to the defect shape can be obtained, the number of measurements can be reduced, and the amount of measurement data to be managed can be reduced.
In addition, since the relative positional relationship between the surface shape of the subject and the internal defect shape can be clearly displayed, the information can be simultaneously displayed on the display screen, so that a clear and easy measurement result can be obtained.

[Brief description of the drawings]

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

FIG. 2 is a diagram showing a shape of a surface of a subject and a shape of a defect inside the subject.

FIG. 3 is a timing chart showing a relationship between an echo signal and a gate.

FIG. 4 is a diagram showing measurement images by a one-gate type and a two-gate type.

FIG. 5 is an external perspective view showing an example of a subject.

FIG. 6 is a diagram showing an example of a defect shape of each layer.

FIG. 7 is a timing chart showing a positional relationship between a reflected echo signal and each gate.

FIG. 8 is a diagram showing an image of each defect simultaneously displayed on the screen.

[Explanation of symbols]

 Reference Signs List 11 sample stage 13 subject 15 three-axis scanner 16 ultrasonic probe 31, 33 gate

Claims (4)

[Claims] 1. An object is irradiated with ultrasonic waves in a pulsed manner, receives ultrasonic waves reflected from the object and returns, detects an echo signal from a received signal by a gate, and converts the echo signal into an image. An ultrasonic exploration imaging method for converting data into data and displaying a measurement image on a display device using the image data obtained at each measurement point, wherein the gate comprises at least two independent gates, and one gate is a surface echo The other gate detects an internal defect echo signal, and the display device displays both a surface shape image based on the surface echo signal and an image of the internal defect shape based on the internal defect echo signal on the display device. An ultrasonic exploration imaging method characterized by displaying a relative positional relationship between shapes. 2. An image of a surface shape based on the surface echo signal and an image of an internal defect shape based on the internal defect echo signal are combined and displayed in a superimposed manner. Ultrasound imaging method. 3. The ultrasonic search according to claim 1, wherein a different color is added to each of the image of the surface shape based on the surface echo signal and the image of the internal defect shape based on the internal defect echo signal. Picture method. 4. An image of an internal defect shape based on the other internal defect echo signal, detecting another internal defect echo signal instead of the surface echo signal, and an image of an internal defect shape based on the internal defect echo signal. The ultrasonic exploration imaging method according to any one of claims 1 to 3, wherein