JPS6078346A - Ultrasonic imaging device - Google Patents

Abstract

PURPOSE:To shorten an imaging processing time by using circularly a picture memory having a finite capacity to image continuously an object to be examined along a long course. CONSTITUTION:A probe 1 scans the surface of the object 14 to be examined, and an ultrasonic transmitting/receiving part 21 is used to digitize a receiving signal in a waveform storage part 22. The coordinates of ultrasonic transmission/reception points are detected by a position detecting part 23 and are digitized by a position signal converting part 24 and are inputted to a coordinate generating circuit 27. Delay time data is inputted to the circuit 27 also. Image data in an area where the imaging processing is terminated is outputted to an external image recording part 34 by a reading circuit 31. An image initializing circuit 32 is used to initialize the picture memory 26 terminated the imaging processing. This area is used for the operation of the next area to perform the imaging processing. In the imaging processing, the output data from the storage part 22 are allocated and are accumulated in the memory 26 with the circuit 27. The memory 26 is used for image formation, and images are outputted to an image display part 35 and an image recording part 36 through a storage part 34 and are monitored and recorded, thus shortening the processing time.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to an ultrasonic imaging device that transmits and receives ultrasonic waves to form and display cross-sectional images and planar images of a subject, and is particularly applicable to flaw detection over a wide range. The present invention relates to an ultrasonic imaging device suitable for an ultrasonic flaw detection device.

[Background of the invention]

Conventionally, in ultrasound imaging equipment that transmits and receives ultrasound waves at multiple points and synthesizes the received data from multiple points to form and display cross-sectional or planar images of the object, When performing continuous visualization, the image memory used to form images could only handle a limited area;
The drawback was that continuous image formation was not possible.

[Purpose of the invention]

An object of the present invention is to provide an ultrasound imaging apparatus that can realize continuous imaging of a subject along a long path.

[Summary of the invention]

The present invention focuses on an area in the image memory where calculations have been completed, initializes the image memory in the area where calculations have been completed, and uses the image memory of a finite size when used as memory for other areas. discovered that continuous image formation was possible, and realized continuous imaging of a subject along a long path.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings. 1st
The figure is an explanatory diagram of the principle of an aperture synthesis method that allows image formation with high resolution. The ultrasonic transmitting/receiving point 11 is expressed as a vector by rI+, and the reflectance at the position r of the subject 14 is ρ.
(r), the ultrasonic transmission waveform is s t (t), and the speed of sound is V. If the pulsed transmission waveform SL (t) is used, the ultrasonic transmission and reception point r and the reflectance ρ (r) position r
Since a reflected echo is obtained by going back and forth, the received signal Sr
(r, t) is 21r-r,,l S-(rs, t)-/ρ(r)・5t(t,) d
r・・・・・・・・・・・・(1) It can be expressed as follows. Here, it is assumed that attenuation during propagation of ultrasonic waves is compensated. Received signal Sr for transmission/reception point r8
(rg, t:), the reflection distribution ρ(r
), in the aperture synthesis method, the intensity distribution of the reconstructed image is
(r,) then 21ral 2 Hru) = Σ8. (rs) - (2) Form an image with rBv. Figure 2 shows how the image is formed.

Image formation may be performed according to equation (2). The received signal S, (rs, t) centered around the ultrasonic transmitting/receiving point 11
are added and accumulated concentrically on the image reproduction surface 16. As shown in FIG. 2, an intersection of circular arcs is formed at a position corresponding to the point reflection source 12, and a reconstructed image 13 of the point reflection source 12 is formed.

Here, the resolution δ of image formation in the azimuth direction can be expressed using the directivity angle ε of the ultrasound beam used and the wavelength λ of the ultrasound. If the directivity angle ε is set to 60°, a azimuthal resolution of one wavelength can be achieved.

The probe actually used has a finite directivity angle ε, that is, the ultrasonic irradiation range is a finite area. In the reproduction calculation for image formation as well, it is sufficient to perform the calculation based on the smell only with respect to the ultrasound irradiation area.

Next, consider a case where the object is visualized along a long path. FIG. 3 shows the case where the probe is scanned in a straight line and the cross section thereof is displayed as an image. In the conventional imaging device, since the playback area 17 is limited, a2 + b2 + C2
+ '2 area could only be handled. next a3
In order to reproduce the area + b3 H'3 + d3, it was necessary to reset the settings and perform calculations.

Here, when reproducing the area a2 + b2 + C2 + d2, x(, -X8 is required as the ultrasonic transmission/reception point. By the way, for the area a2, X.

Transmission/reception points up to x4 are required, but the ultrasonic beams do not irradiate 22 at x5 to x8, so they do not contribute to image formation calculations. Therefore, we have found a method of outputting the image data of a2 for which the calculation has been completed to the outside and using it for calculation of the next region a3. FIG. 4 shows the area side of the image memory and external image storage data. First, image memory 261
is a combination of received signals from ultrasonic transmitting/receiving points Xo to x4. At that point, the external image storage unit 341 stores a
It is assumed that data at both ends of areas 1 to d are included. Assuming that the next ultrasonic wave transmission/reception point is X5, the image forming process has been completed in area 22 of the image memory 261. Therefore, the image data of area a2 is stored in the external image storage unit 341.
A2 is added to the external image storage unit 342.

Furthermore, the area where 82 of the image memory was stored is initialized to set the image memory to 262. Next, the received signal at the position x6 is processed to form an image. The area initialized here is newly used for area a3, and area allocation υ of the image memory subjected to visualization processing is shown in 263. Similarly, the area b2 of the image memory is initialized when the imaging process is completed and used for bB.

By repeating the above operations, continuous image formation along a long path can be realized.

FIG. 5 shows a block diagram of the configuration of this embodiment. First, the probe 1 is scanned over the surface of the subject 14. Ultrasonic waves are transmitted and received using an ultrasound transmitting and receiving section 21, and the received signal is digitized and stored in a waveform storage section 22. At the same time, the coordinates of the ultrasonic transmitting and receiving points are detected by the position detection section 23, digitized by the position signal conversion section 24, and inputted to the write-in coordinate generation circuit 27 which generates the write address of the image memory. Outputs the received data of the received signal from the waveform storage unit, and
All delay time data is input to the write coordinate generation circuit 27. Here, the image reading circuit 31 outputs the image data of the area for which the visualization process has been completed to the external image storage section 34. Next, the image initialization circuit 32 is used to initialize the image memory 26 in which the above imaging process has been completed. Next, as explained in FIG. 4, the initialized area is used for calculation of the next area to perform imaging processing. Visualization is performed using the waveform storage unit 2.
Write the received data output from 2 and assign circuit 2
7 to add and accumulate in the image memory. Image formation is performed using the image memory 26, but the image storage is outputted to the image display section 35 and the image recording section 36 via the external image storage section 34 for monitoring and recording. Note that address generation for the image readout circuit 31 and the image initialization circuit 32 is performed by an image initialization address generation section. Further, the entire control of this device is performed by a control section 20.

According to this embodiment, it is possible to continuously execute the imaging process for a long path, and the continuous image formation described above can be performed simply by storing the image memory of the area where the maximum ultrasonic waves are irradiated. Can be executed. Another advantage is that only one system of imaging processing circuit is required.

〔Effect of the invention〕

According to the present invention, by cyclically using a finite size image memory, it is possible to realize continuous imaging of a subject along a long path, and to shorten the imaging processing time. effective.

[Brief explanation of the drawing]

Fig. 1 is a diagram of the principle of image formation using the aperture synthesis method, Fig. 2 is a model of image formation, Fig. 3 is a model of image formation along a long path, and Fig. 4 is a method of dividing and using image memory. FIG. 5 is a block diagram of the configuration of the device. 21... Ultrasonic transmitter/receiver unit, 26... Image memory, 3
1... Image reading circuit, 32... Image initialization circuit, 34... External image storage section. 1st Kasumi Katsu 2El Mouse, 5S /7 Foil 4 stitches 63

Claims (1)

[Scope of Claims] An ultrasound imaging device that transmits and receives 1° ultrasound and displays a cross-sectional image or a planar image of a subject using the received data,
Among one or more image memories storing image data,
An ultrasound imaging device characterized in that image data of an image memory of an area where calculation has been completed is outputted to the outside, and then initialized and used as an image memory of another area. 2. An ultrasound imaging apparatus according to claim 1, comprising an image recording section for recording image data of an image memory outputted to the outside. 3. The ultrasound imaging apparatus according to claim 1, characterized in that it has a function of allocating received data to an initialized area as well.