JPS6196460A - Method and apparatus for displaying ultrasonic video - Google Patents

Abstract

PURPOSE:To attain a high speed scanning by scanning an ultrasonic transducer in both positive and negative directions and converting an ultrasonic wave receiving signal in one direction into a video signal. CONSTITUTION:A high voltage electric pulse generated from an ultrasonic flaw detector 29 is applied to the ultrasonic transducer 21 through a scanner 24 and the generated ultrasonic pulse is irradiated to a subject 23 to be tested. A reflected signal from the internal defect 28 of the subject 23 is inputted to a flaw detector 29 through the transducer 21 and the scanner 24,amplified and outputted as an ultrasonic receiving signal 27. The transducer 21 is driven by the scanner 24, a positional signal 26 and a scanning direction signal 11 are outputted from the scanner 24. When the scanner 24 is reciprocally scanning in the positive and negative directions, the signal 11 is outputted so that a gate is set up to the opened level in the positive scanning or as a gate to the closed level in the negative scanning. Therefore, the signal 27 is inputted to a video device 13 through a gate circuit 12 in the positive scanning, but is interrupted at the negative scanning. The device 13 synthesizes a scanning video signal 14 from the signals 27, 26 and displays the synthesized video signal 14 on a display unit 15.

Description

[Detailed description of the invention] [Industrial application field 1 [Conventional technology] The conventional technique of τ will be explained with reference to FIG.

According to the conventional method of displaying ultrasonic flaw detection results as images, a finely focused ultrasonic wave beam 22 is generated from an ultrasonic transdecoder IJ-21 using a high-pressure pulse generated by an ultrasonic flaw detector 21). While irradiating the specimen 23, the reflected signal from the specimen 23 is received by the ultrasound transducer 21 and amplified by the ultrasound probe (mouthparts 29).

This ultrasonic transducer 21 is coupled to a scanner 24 and repeats reciprocating motion in both forward and reverse directions on a fixed scanning surface 25 to scan within a predetermined rectangular area. The position of the ultrasonic transducer 21 on the scanning plane 25 can be known by means of the device signal 2G constituted by the scanner 24. The ultrasonic flaw detection results are displayed as a two-dimensional image from this position signal and the ultrasonic receiving IT number 27.

An example of a flaw detection image obtained in this way is conceptually shown in FIG. 3. The surface image 31 and the internal defect image 32 correspond to the object 23o and the internal defect 28 in FIG.

Now, when area A in FIG. 3 is enlarged and displayed, it can be seen that the display position is shifted depending on the forward direction and reverse direction of scanning as shown in FIG. 4. This becomes a particular problem when performing ultrasonic flaw detection on a minute object by scanning and enlarging and displaying the results. For example, as shown in FIG. 5, an image that is originally a perfect circle is expressed as if it were an ellipse due to a shift in the display position. This causes large errors in recognizing the shape of the object and measuring the spread of internal defects in ultrasonic flaw detection, making quantitative flaw detection extremely difficult.

This display misalignment may be due to the mechanical precision of the scanner itself, physical defects related to the nature of internal defects and the incident angle of the ultrasound beam, or may occur during signal processing and image display. Due to electrical errors caused by
It is thought that -C occurs due to their combined action during scanning.

However, even if we try to eliminate these causes by conventional means, such as improving the mechanical precision of the scanner, C has certain limitations, especially when the cause is due to the physical behavior of ultrasound. The solution was extremely difficult. In particular, when magnifying and displaying the flaw detection results of a minute object, the deviation of the display position will also be magnified, which requires unrealistically high mechanical and electrical precision to eliminate this. It is becoming increasingly difficult to realize practical devices in response to these demands.

[Problems to be Solved by the Invention] The purpose of the present invention is to eliminate deviations in the display position of defects caused by causes related to scanning in ultrasonic flaw detection imaging, and in particular to solve Improving quantitative quality
There are many things.

[Means and actions for solving the problems] According to the present invention-
(, an ultrasonic wave L that moves and moves alternately in two mutually opposite directions)
The transducer receives only the ultrasound signal reflected from the object while moving in one direction, and generates an image from this ultrasound signal and the position signal of the transducer, thereby eliminating the positional shift of the defective image. do. An image of a defective area created during scanning in one direction and an image of a defective area created during scanning in the other direction may have little positional deviation within each image, but there may be positional deviation between the images. Therefore, rather than combining these images to make the final image, one of the images is selected as the final image, and the reduction in resolution at that time is prevented by reducing the size of the scanning line. Do it like this.

Video selection is performed using a scanning direction signal from the scanner. Therefore, according to the present invention, scanning direction signals having different levels for one direction scanning and other direction scanning are generated in the scanner,
The ultrasonic reception signal is applied to a gate circuit that opens with a scanning direction signal representing scanning in either direction. 1 image from the ultrasonic reception signal selected by the gate circuit and the transducer position signal from the scanner! do.

L Example J FIG. 1 shows an example of the present invention. In the figure, high-voltage electric pulses generated by an ultrasonic flaw detector 29 are applied to an ultrasonic transducer 21 via a scanner 24, and the generated ultrasonic pulses form a beam and irradiate the object 23. . The reflected signal from the internal defect 28 is again converted into an electric pulse by the ultrasonic transducer 21, enters the ultrasonic flaw detector via the scanner, is amplified, and is output as an ultrasonic reception signal Ci 27.

The ultrasonic transducer 21 is driven by a scanner 24 to scan a predetermined flaw detection surface, and the position and direction during scanning I3L are outputted from the scanner 24 as a position signal 26 and a scanning direction signal 11, respectively. be done.

Next, the ultrasonic receiver fi; (i'') is controlled by the scanning direction signal 11 in the gate circuit 12 as follows according to the present invention. When scanning a rectangular area, the scanning direction signal 11 is output at the gate-to-gate level during forward scanning, and the scanning direction signal 11 is output at the gate-to-gate level during reverse scanning.Therefore, the light and sound wave reception signal passes through the gate circuit 12 and is input to the acid blowing device 13 during normal scanning, but is blocked during reverse scanning. are combined and sent to the display 15 to display an ultrasonic detection 1M image.

This gate circuit 12 may be an independent circuit as shown in FIG. 1, or may be incorporated inside the video device 13. Further, as the display device 15, it is preferable to use a recording device such as a cathode ray tube display device, a printer, or a printer.

An example of the results of scanning flaw detection using the embodiment shown in Fig. 1 is shown in Fig. 6.
As shown in the figure. In the same figure, the solid line indicates that when the gate circuit 12 is open, the ultrasonic reception signal is input and the scanned image is transmitted to the display 1.
5, and the chain line indicates a portion 62 that is not displayed because the gate circuit 12 is in a closed state. The edges of the internal defect image 32 were displayed smoothly, and the size and shape matched well with the verification results from the destructive test of the test object 23.

In this embodiment, since data is not lost during reverse direction scanning, the scanning pitch (scanning line interval) of the operating device 24 is set in advance.
was set to 1/2 of the conventional value to prevent reduction in resolution. Moreover, since the scanning speed was set to double at the same time, the total scanning time was almost the same as in the conventional method. The reason why the scanning speed could be increased in this way is that it became possible to remove from the displayed image the mechanical positioning errors of the scanner that tend to occur at high speeds. The scanning speed can be set to a higher speed η if necessary, thereby reducing the operation time.

FIG. 7 shows another embodiment of the method of the invention. In the above explanation, the gate circuit was opened by treating the rightward operation as a positive direction operation as shown in Figure 7-1, but the leftward direction may be used as a positive direction as shown in Figure 7-2. Further, 1. The scanning line does not need to coincide with the horizontal direction of the display screen, and may be in the vertical direction or inclined.

Rough scanning does not need to be limited to linear scanning, and may be any non-linear scanning or scanning in which scanning lines in forward and reverse directions are non-parallel.

[Effects of the Invention] According to the present invention as described above, when displaying an ultrasonic flaw detection image of an object by scanning a rectangular area in both forward and reverse directions using an ultrasonic transducer, the By visualizing the ultrasonic reception signal in either direction scanning or reverse direction scanning, the defect display position shift error was removed and the quantitative nature of the ultrasonic flaw detection image was significantly improved. It has become possible to perform high-speed scanning without increasing the defect display position deviation error, and it has become possible to shorten the scanning time.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the ultrasonic image display device of the present invention. FIG. 2 is an inclined view of the scanning ultrasonic flaw detection device. FIG. 3 shows an example of 10 images of ultrasonic detection using the conventional method. FIG. 4 is an enlarged view of area A in FIG. FIG. 5 shows an example of positional deviation of defect display. Figure 7A6 shows an example of defect display obtained by the method of the present invention. FIG. 7-1 shows a forward scanning display according to the present invention, and FIG.
The figures each show a reverse scan display according to the invention. 1: scanning direction signal, 12: gate circuit, 13: video device, 14: scanning video signal, 21: ultrasound transducer, 22: ultrasound beam, 23: subject, 24: scanner,
26: Position signal, 21: Ultrasonic reception signal, 29. : Ultrasonic flaw detector, 25: Scanning surface, 28: Internal defect, 31: Surface image, 32: Internal defect image, 61: Table 41 section, 62
: Part that was not displayed.

Claims (1)

[Claims] 1. An ultrasonic image display characterized by moving an ultrasonic transducer alternately in two mutually opposite directions and generating an image from an ultrasonic signal received while moving in one direction. Method. 2. A scanner that moves an ultrasonic transducer alternately in two mutually opposite directions; a scanning direction that represents scanning in one direction by receiving a scanning direction signal from this scanner and an ultrasonic signal from the ultrasonic transducer; a gate circuit that outputs an ultrasonic signal in response to an applied signal; and a gate circuit that outputs a scanning video signal in response to the ultrasonic signal from the gate circuit and a position signal representing the position of the ultrasonic transducer from the scanner. An ultrasonic image display device characterized by being equipped with a video device.