JPS6227393B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a frame memory device used in an ultrasonic diagnostic apparatus. More specifically, the present invention relates to the configuration of a frame memory device that stores echo images converted into digital data.

2. Description of the Related Art Ultrasonic diagnostic apparatuses that emit ultrasonic waves to an object to be examined and display an image of the object on a CRT based on the reflected waves are conventionally known. This type of device has a frame memory that converts the reflected wave (echo signal) into digital data using an analog-to-digital converter (hereinafter simply referred to as an A/D converter) and stores the digital data. The data stored in the frame memory is processed by a digital-to-analog converter (hereinafter simply D/A converter).
converter) is used to demodulate the signal into an analog voltage. The demodulated analog voltage (image signal) is
It is applied to the CRT, and an echo image of the object to be examined is displayed on the CRT.

FIG. 1 is a diagram showing an example of a CRT display of an echo image displayed in this manner. In the figure, 10 is a CRT and 11 is an echo image. Generally, such a CRT display uses a raster scan method. In such a raster system, the contents of the frame memory are scanned horizontally as shown in the figure in order to display them in a manner that naturally appeals to human vision. On the other hand, echo images occur in a direction perpendicular to the scanning direction. Therefore, reading out of the memory for display on a CRT must be performed in the horizontal direction, while writing image data into the memory must be performed in the vertical direction. In order to maintain real-time performance, the above writing and reading processes need to be performed at high speed.

In the conventional image processing method, the conventional apparatus performs a write operation using the retrace time of horizontal scanning or vertical scanning, that is, when reading is stopped. In such a method, the number of data that can be written is limited because the retrace time is short (especially in the horizontal scanning direction). Therefore, there is a drawback that high-speed processing cannot be performed to obtain the necessary images.

The present invention has been made in view of the above points, and the present invention has been made in view of the above points.
and a second memory, and when the first memory is being read, image data is written to the second memory, and conversely, when the second memory is being read, image data is written to the first memory. The present invention has realized a frame memory device that can transfer a large amount of data to an image memory at high speed without affecting reading for CRT display. Hereinafter, the present invention will be explained in detail with reference to the drawings.

FIG. 2 is an electrical connection diagram showing one embodiment of the present invention. In the figure, 1 is an A/D converter that converts an input echo signal into digital data. The echo signal is A/D converted at each sampling point in the horizontal and vertical directions. 2 and 3 are
This is an auxiliary memory that alternately stores the outputs of the A/D converter 1. SW ₁ is a switch for selecting either auxiliary storage memory 2 or 3. 4 is a first image memory A, and 5 is a second image memory B.
The auxiliary storage memories 2 and 3 are the image memories A,
They are each divided into two parts corresponding to B. In the auxiliary storage memory 2, a portion that stores data to be transferred to the image memory A is A', and a portion that stores data to be transferred to the image memory B is B'. The auxiliary storage memory 3 is similarly divided into A'' and B''.

Memory, A', A'' parts are connected to image memory A via switch SW ₂ , and B', B'' parts are connected to image memory A via switch SW 2.
Each image is transferred to image memory B via SW ₃ . Outputs from the image memories A and B are selected by a switch SW ₄ and sent to the D/A converter 8. The D/A converter 8 demodulates the captured digital data into an analog image signal. The demodulated analog signal is sent to the CRT. CRT is
In response to this analog signal, an echo image as shown in FIG. 1 is displayed.

6 is a display control circuit that controls switching of the switch SW ₄ . 7 is a write control circuit that controls switching of the switches SW ₂ and SW ₃ . Switch SW ₁ ~ _{SW 4}
Because high-speed performance is required, semiconductor switches are used in all cases. The operation of the circuit configured in this way will be explained below.

Assume that the contents of image memory A are now being read. The switch SW ₄ is connected to the image memory A side. During this time, the contents of the auxiliary storage memory 2 or 3 are sequentially written into the image memory B. At this time, the switch SW ₃ is operated, and the switch SW ₂ is open. The contents of B'' in memory 3 are stored in image memory B.
The A/D converter 1 outputs data even while data is being written. The output data at this time is stored in another unused memory 2. At this time, the switch SW ₁ is connected to the memory 2 side. B'' contents of memory 3 are written to image memory B.

When the contents of the image memory A are output for one raster, the switch SW ₄ is connected to the image memory B side, and the contents of the memory B are read for one raster. During this time, the data stored in A'' of the auxiliary storage memory 3 is written to the image memory A. During this time, the switch SW ₁ is connected to the memory 2 side and the A/D converter 1
The output data is stored in the auxiliary storage memory 2.
After writing to memory 2 is completed, write to memory 2.
The contents of A' are written to image memory A. During this time, the output of the A/D converter 1 is stored in A'' of the memory 3. By repeating the above operation, the output of the A/D converter 1 is stored in the image memories A and B.
Writing and reading are performed.

According to such a method, a large amount of data can be transferred because the writing time is not particularly restricted compared to the writing method using the retrace time as in the conventional device. Furthermore, since the image memories A and B can be used alternately for reading and writing, efficiency is high and high-speed processing is possible.

As described above in detail, according to the present invention, it is possible to realize a frame memory device that can perform high-speed processing and transfer a large amount of data by efficiently controlling the reading and writing of an image memory divided into two parts. .

[Brief explanation of the drawing]

Figure 1 is a diagram showing an example of displaying an echo image, Figure 2
The figure is an electrical connection diagram showing one embodiment of the present invention. 1... A/D converter, 2, 3... Auxiliary storage memory, 4, 5... Image memory, 6... Display control circuit, 7... Write control circuit, 8... D/A converter,
10...CRT, 11...Echo image, SW ₁ ~
SW ₄ ...Switcher.

Claims (1)

[Scope of Claims] 1. A frame configured to read and write data in different directions to a memory that stores image data, and to read and output data in an order suitable for a display device that uses a raster scan method. A memory device that stores echo signal data for one scan2.
a first image memory and a second image memory that are memories that store data in the auxiliary memory, and that divide image data for one display image into two and store each of them; Either one of the two auxiliary storage memories is
an auxiliary storage memory switch that selects and guides echo signal data for each scan; and a case of selecting whether or not to supply data from the two auxiliary storage memories to the first image memory; A symmetrical selection operation is performed between a first image memory input switch for retrieving data from either one of the two auxiliary storage memories, and the first image memory input switch. Select whether or not to supply data from the two auxiliary storage memories to the second image memory, and if selected, select the second image memory for retrieving data from either one of the two auxiliary storage memories. an image memory input switch; an image memory output switch that selectively selects the first image memory and the second image memory to output read data; and controls each of the switches as appropriate. and a control means for alternately reading and outputting contents from the first image memory and the second image memory for each raster, and outputting the contents to the image memory from which the reading is not being performed, one of the auxiliary storage memories in which the echo signal has already been stored;
It is controlled to read and input data from the memory area corresponding to the area to be stored in the image memory, and it is possible to input data into the image memory at high speed and in large quantities without affecting the readout from the image memory that supports raster scan display. A frame memory device characterized in that it is capable of data transfer.