JP3337618B2 - Ultrasound diagnostic equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an ultrasonic diagnostic apparatus, and more particularly to an ultrasonic diagnostic apparatus capable of simultaneously displaying a plurality of ultrasonic images.

[0002]

2. Description of the Related Art The operation modes of an ultrasonic diagnostic apparatus include:
B mode for displaying a two-dimensional tomographic image, M mode for displaying the temporal change of the luminance distribution on the ultrasonic beam as a sweep image, Doppler flow mode for displaying a two-dimensional Doppler image in color, temporal change of the Doppler frequency distribution at a certain point Various operation modes, such as a power spectrum mode (Doppler mode) in which is represented as a sweep image, are known. Note that these modes can be broadly classified into a mode for forming an image corresponding to a two-dimensional cross section and a mode for forming a sweep image with a time axis as a horizontal axis.

Generally, an ultrasonic diagnostic apparatus is provided with a function capable of simultaneously displaying a plurality of ultrasonic images as described above. This is to display a B-mode image in the upper half and an M-mode image in the lower half, for example. There are various other combinations, such as a combination of a B-mode and a power spectrum image and a combination of two B-mode images.

[0004]

However, in the prior art, after simultaneously displaying a plurality of ultrasonic images, the image data in the display memory is frozen (saved / fixed) and only one of the images is enlarged. It was not possible to display one image, or it was necessary to separately install a large-capacity memory in the apparatus. This will be described below.

FIG. 9 shows a basic configuration of a conventional ultrasonic diagnostic apparatus. In FIG. 9, ultrasonic waves are transmitted and received by a probe 10 which is an ultrasonic probe. The transmission / reception unit 12 performs transmission control and reception control of ultrasonic waves. The image processing unit 14 is a unit that forms an ultrasonic image based on a received signal. The display device 16 displays an ultrasonic image.

FIG. 10 shows a first example of the image processing unit 14 shown in FIG.
Is shown. The received signal (echo data) from the transmission / reception unit 12 is converted into a digital signal in the A / D converter 18. In the echo data processing circuit 20, processing such as interpolation processing and coordinate conversion for the echo data is executed, and the image data obtained by the processing is stored in the display memory 2.
2 is written. The display memory 22 is a so-called frame memory, and stores each image data (echo data) in the form of a display image. Image data is read from the display memory 22 in accordance with raster scanning in the display device, and the image data is subjected to gamma correction and luminance conversion in the image signal processing circuit 24, and the processed image data is transmitted to the D / A converter 26. After being converted back to an analog signal, it is output to the display device 16.

As described above, the display memory 22 stores image data for one frame of the display screen. In the configuration example shown in FIG. 10, no other memory for storing image data is provided. Therefore, in this configuration,
When a plurality of ultrasonic images are displayed at the same time, the image is reduced when image data is written to the display memory 22,
Thus, the plurality of reduced ultrasonic images are written in the display memory 22. And the display memory 2
By performing readout from Step 2 in accordance with raster scanning, a plurality of ultrasonic images were simultaneously displayed.

FIG. 11 conceptually shows the contents of the display memory when the configuration of FIG. 10 is adopted.
As shown in (A), in the case of the single image display mode, image data for one ultrasonic image is stored in the display memory 22 as it is. On the other hand, as shown in (B), in the case of the two-image display mode, the display memory is divided into two, and the reduced image data of one screen is stored.

Therefore, in the above configuration, in the case of the two-image display mode, since the image data is stored after the image data is reduced, a freeze operation is performed to enlarge only one of the ultrasonic images. Could not be displayed. For example, it is possible to enlarge an image by data interpolation, but in that case, a complicated operation must be separately performed, and there is a problem that image quality is reduced.

Therefore, a configuration as shown in FIG. 12 has been put to practical use. This is a configuration generally employed in high-end machines. 12, a large-capacity memory 30 is provided before the display memory 22. As shown on the left side of FIG. 13, a large number of ultrasonic images are stored in the large-capacity memory 30 according to the operation modes. Then, the ultrasonic image to be actually displayed is once transferred to the display memory 22 and then read out and displayed.
In this case, in the case of the two-image display mode shown in the upper right part of FIG. 13, a reduction process is performed on the image data when the image data is transferred to the display memory 22. When it is desired to obtain a magnified display of one of the images by performing the freeze operation after displaying the two images, as shown in the lower right part of FIG.
The image data of the image is transferred to the display memory 22 without being reduced, and the image data read therefrom is displayed. Therefore, in this case, the image can be freely enlarged after the freeze, and the image quality does not deteriorate.

However, according to this configuration, it is necessary to provide a large-capacity memory in the device, and there is a problem that the peripheral circuit configuration becomes large-scale in proportion to the large-capacity memory, thereby increasing the cost of the device.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and an object of the present invention is to display a plurality of ultrasonic images at the same time without simultaneously increasing the cost of the ultrasonic diagnostic apparatus. Is to be able to enlarge and display any of the ultrasonic images with good image quality.

[0013]

[Means for Solving the Problems]

(1) In order to achieve the above object, the present invention provides an ultrasonic diagnostic apparatus capable of displaying N ultrasonic images side by side on the same screen, wherein the memory comprises N storage planes. A display memory in which a plane has a storage capacity for one frame; and a writing control means for writing image data to one of the storage planes in the single display mode and writing image data of each ultrasonic image to each storage plane in the multiple display mode. Means for reading image data from the display memory at the display timing of the display, wherein the image data is read from any of the storage planes in the single display mode, and the image of each image is read from the plurality of storage planes in the multiple display mode. Read control means for reading out data while thinning the data, wherein the read control means comprises an image for each image in the multiple display mode. And executes a thinning read in accordance with the equation.

According to the above configuration, N (= 2, 3,...)
・) It is possible to simultaneously display two ultrasonic images side by side. In this case, each image data is stored in each storage plane of the display memory without being reduced. Then, at the time of reading out the image data, thinning-out is performed according to the image format or the like, and thereby the image is reduced.
That is, in the present invention, since the thinning is performed not at the time of storage in the display memory but at the time of reading, even if there is a request for enlarged display later, the request can be met only by reading the stored data.

(2) In a preferred aspect of the present invention, when the two-dimensional sectional image is displayed in the multiple display mode, the readout control means controls the image data in both the vertical and horizontal directions. When the image in the sweep format in which the horizontal sweep is performed is displayed, the thinning read is performed only in the vertical direction.

In the case of an image having the form of a two-dimensional section, since the reduction ratios in the vertical and horizontal directions need to be the same, thinning is performed to realize the same reduction ratio in both the horizontal and vertical directions. . On the other hand, in the case of a sweep image, the horizontal direction is a time axis, and there is a strong demand for maintaining a constant sweep speed. Therefore, thinning is not performed in the horizontal direction but is performed only in the vertical direction.

(3) In a preferred aspect of the present invention, the display memory is constituted by a plurality of memory chips having address terminals commonly connected to each other for the same address, and the plurality of memory chips include a horizontal display image. A display address is sequentially allocated along at least one of a direction and a vertical direction, and the read control unit selects image data simultaneously output from the plurality of memory chips according to the display mode and the image format. It has a chip selector.

According to the above configuration, thinning in the horizontal and vertical directions can be realized by selecting the chip output. Therefore, with a simple configuration, it is possible to reduce an image and enlarge it thereafter.

(4) In a preferred aspect of the present invention, the display image space on the display memory is divided into pixel blocks each including four pixels, and the pixel data of the upper left pixel in each pixel block is stored in the first memory chip. The pixel data of the upper right pixel in each pixel block is stored in the second memory chip, the pixel data of the lower left pixel in each pixel block is stored in the third memory chip, and the pixel data of the lower right pixel in each pixel block is stored. The data is stored in the fourth memory chip.

(5) In a desirable mode of the present invention, when the ultrasonic image is reduced to one fourth by thinning out the pixel data in both the horizontal direction and the vertical direction, a specific one of the four memory chips is specified. When the image data from only the memory chip is used and the image data is thinned out only in the vertical direction to reduce the image in the vertical direction by half,
Image data from only the first and second memory chips or only the third and fourth memory chips among the four memory chips is used.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a main configuration of an ultrasonic diagnostic apparatus according to the present invention. Specifically, the configuration of the image processing unit according to the present embodiment is shown. The configuration of the entire apparatus is the same as that shown in FIG.

The received signal (echo data) output from the transmitting / receiving section is converted into a digital signal by the A / D converter 18. The echo data converted into a digital signal is input to the echo data processing circuit 20. The echo data processing circuit 20 executes processing such as interpolation of echo data and coordinate conversion. The echo data output from the echo data processing circuit 20 is stored in the display memory 34 via the selector 46.

In the present embodiment, the display memory 34
In order to display two ultrasonic images simultaneously, it has two storage planes. That is, it has a first plane 36 and a second plane 38. These storage planes exist virtually, and as will be described later, the display memory 34 actually has four memories (memory chips).
It is composed of

The echo data output from the display memory 34 is input to the image signal processing circuit 24 via the selector 50. The image signal processing circuit 24 performs processing such as gamma correction and luminance conversion on the echo data. The image signal output from the image signal processing circuit 24 is returned to an analog signal by the D / A converter 26. Thereafter, the image signal is output to the display device.

A write controller 40 is provided to control the writing of echo data to the display memory 34. The write control unit 40 includes a write control circuit 44 and a selector 46. On the other hand, the display memory 34
A read control unit 42 is provided to control the reading of echo data from the CPU. This read control unit 42
Is configured by a read control circuit 48 and a selector 50. The specific operation of each of these circuits will be described in detail below.

The control section 52 controls the write control circuit 44 and the read control circuit 48. The control is performed based on inputs from a mode selector 56 and a freeze switch 54.

When displaying only a single ultrasonic image, the writing control unit 40 shown in FIG. 1 executes control for storing image data in only one of the first plane and the second plane. I do. For example, when displaying only the B-mode image, only the first plane 36 is selected by the selector 46, and the image data of the B-mode image is sequentially stored in the first plane. On the other hand, the write control unit 40
When the two-image display mode in which two ultrasonic images are arranged and displayed simultaneously is selected, the selector 46 sorts each echo data to the corresponding storage plane. That is, for example, the image data of the B-mode image is stored in the first plane 36, and the image data of the M-mode image is stored in the second plane 38.

Therefore, the write control unit 40
As a result, each storage plane stores the image data of the ultrasonic image for one frame. In the present embodiment, a reduction process such as thinning out of data is not executed when writing image data to the display memory 34 as in the related art. Data thinning is performed when image data is read from the display memory 34 as described below.

The read control section 42 is a circuit for appropriately selecting echo data output from each storage plane of the display memory 34 and outputting the selected echo data to the image signal processing circuit 24. Specifically, when the one-image display mode is selected, only the image data stored in any one of the storage planes is passed through the selector 50, and the ultrasonic image is displayed as it is. On the other hand, in the case of the two-image display mode, the image data from the first plane 36 is selected by the selector 50 when displaying the upper half of the screen, for example. Image data from the two planes 38 is selected.

The mode selector 56 functions as a means for selecting one image display mode or two image display mode.
It also functions as means for selecting the type of ultrasonic image to be actually displayed in each mode. In the present embodiment, for example, two ultrasonic images of the same type can be displayed simultaneously. The freeze switch 54 is a switch for preventing image data stored in the display memory 34 from being overwritten and storing the image data. This switch is operated, for example, when executing two-image display in real time and wanting to stop the image at a certain time phase and enlarge and display one of the two images.

FIG. 2 shows the state of the display memory 34 during normal operation. Here, an example is shown in which a B-mode image and an M-mode image are displayed vertically and displayed simultaneously.

As shown in FIG. 2, each of the storage planes 36 and 38 of the display memory 34 stores a B-mode image and an M-mode image by real-time processing. When the image data of the B-mode image is read out by the operation of the reading control unit 42 shown in FIG. 1, a thinning-out process for reducing the image by half in both the horizontal and vertical directions is executed. As a result, a B-mode image reduced to a quarter as a whole is displayed. Reference numeral 100 in FIG. 2 indicates a display image. Note that reference numeral 104 in FIG. 2 indicates a blank area. No ultrasonic image is displayed in this area. When an M-mode image is read as shown in FIG. 2, a thinning-out process is performed to reduce the image data by half only in the vertical direction. As a result, the M-mode image is displayed with a display image as indicated by reference numeral 100.

As described above, the B-mode image is an image corresponding to a cross section of the living body, and the scales in the vertical and horizontal directions need to be the same. Therefore, as described above, both the horizontal and vertical directions are used. The same scale is set. On the other hand, since the M-mode image is a sweep image in which the horizontal axis is the time axis and the vertical axis is the depth axis, reduction processing is performed only in the vertical direction to maintain the concept of the time axis which is the horizontal axis. ing.

In the state where the two-image display mode is executed as described above, the freeze switch 5 shown in FIG.
When the data in the display memory 34 is prohibited from being overwritten by operating the button 4, the enlarged display becomes possible as shown in FIG. For example, when the B mode image is enlarged and displayed using the mode selector 56, the B mode image is read as it is and displayed. The same applies to the case of the M mode, and the image data is read out as it is and displayed. Of course, in displaying an image, each pixel data is read out in a reading order according to a raster scan in the display device.

As described above, according to the image processing section of the present embodiment, although the scale of the display memory 34 is slightly increased, a large-capacity memory is not required unlike the related art, and after the freeze is performed by the simple thinning process. And read / write control can be executed on the premise of expansion of.

Next, the writing and reading will be described in more detail. FIG. 4 shows the storage space of the display memory 34. As described above, the display memory 34 is conceptually divided into the first plane 36 and the second plane 38.

The display memory 34 is physically composed of four memories A to D. Then, the storage space is divided into blocks each including four storage cells. Each storage address in each block corresponds to the address of four memories, and if the same block, the address of each memory is also the same. Therefore, when a certain address is specified at the time of writing or reading to the display memory 34, four memory cells are specified for one address specification. For this reason, in the present embodiment,
A selector 46 is provided in a stage preceding the display memory 34, and a selector 50 is provided in a stage subsequent to the display memory 34. The selector 46 and the selector 50 select a chip, that is, select a physical memory. FIG. 5 shows the operation of the selector 50. For example, when an address where the horizontal address x is 0 and the vertical address y is 0 is specified by the address signal 102, four pixel data are specified across four memories corresponding to the address. Become. The selector 50 has a function of selecting and outputting necessary pixel data from the four pixel data.

By connecting the addresses of the four memories in common as in this embodiment, the thinning-out processing can be realized with a simple configuration without increasing the number of address buses or the scale of peripheral circuits, for example. .

For example, when a B-mode image is reduced to one-fourth and displayed as shown in FIG. 2, only image data from the memory A is output to the display device in this embodiment. In addition, only in the vertical direction shown in FIG.
When displaying the reduced M-mode image, the selector 50 outputs the image data from only the memories A and B. Thus, it is possible to select only image data existing on every other horizontal line. Further, when the B-mode image or the M-mode image is displayed as it is as shown in FIG. 3, all the pixel data in the area of the first plane or the second plane shown in FIG. Will be. The above operation will be specifically described with reference to FIGS. In this example, it is assumed that the image data of the B-mode image is stored in the first plane 36 of the display memory 34, and the image data of the M-mode image is stored in the second plane 38.

FIG. 6 shows an operation example in the case of displaying a B-mode image reduced to a quarter as shown in FIG. In this case, the clock shown in FIG.
It is set to 6 MHz. Pixel data having the same address is output in parallel from each memory in synchronization with the rise of the clock. In contrast, selector 5
0 selects only memory A. Then, only the pixel data from the memory A is selectively output as shown in FIG. As a result, the B-mode image is reduced to a quarter. In other words, a similar result can be obtained by selecting a chip without performing a complicated calculation for a thinning target. In FIG. 6, as described above, thinning is performed in both the horizontal direction and the vertical direction.

FIG. 7 shows an operation example in the case of displaying an M-mode image reduced in half only in the vertical direction as shown in FIG. In this case, for example, 8 MHz is set as the read clock shown in FIG. That is, when horizontal thinning is not performed, the clock rate is set to one half. However, the operation in the selector 50 is executed at a rate of, for example, 16 MHz as in the case of FIG. As shown in FIG. 7, four pixel data having the same address are output from the four memories in synchronization with the clock. On the other hand, sampling is performed twice within one cycle of the clock by the selector 50. In this case, pixel data of only the memory A and the memory B is selected in that order.
As a result, pixel data is output in a data array as shown in FIG. Incidentally, as a result of the memory C and the memory D not being selected, the size is reduced by half in the vertical direction. That is, in the operation shown in FIG. 7, the half thinning is executed only in the vertical direction.

FIG. 8 shows the operation in the case of performing normal one-image display and the case of performing freeze after the two-image display mode to enlarge any image. As shown in FIG. 8, a clock rate similar to that shown in FIG. 7 is set, and four data are sequentially output from four memories in parallel in synchronization with the clock. The selector 50 selects either the memory A or the memory B in the even field, and selects the memory C or the memory D in the odd field. That is, the same address is generated twice corresponding to the even field and the odd field, and all the pixel data in the first plane or the second plane is selectively output. Thus, one-image display or enlarged display as shown in FIG. 3 is performed. The read control circuit 48 controls the selector 50 in order to realize the operations shown in FIGS.

In the above embodiment, the display memory 34 is constituted by four physical memories. However, by using more memories, arbitrary reduction ratios in the horizontal and vertical directions can be realized. . In consideration of the device cost and the demands of the user, it is considered best to use four memories as the display memory 34 to perform the above-described operation.

The display start position and the display end position of each image in the reduced state are managed by the read control circuit 48. In the present embodiment, each memory has an 8-bit gradation, but is not limited to this, and a memory having another number of bits may be used.

[0046]

As described above, according to the present invention,
Without incurring a significant cost increase of the ultrasonic diagnostic equipment,
After simultaneously displaying a plurality of ultrasonic images, any one of the ultrasonic images can be enlarged and displayed with good image quality.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of an image processing unit in an ultrasonic diagnostic apparatus according to the present invention.

FIG. 2 is a diagram illustrating an operation in a two-image display mode.

FIG. 3 is a diagram showing an operation of one image display (enlarged display).

FIG. 4 is a conceptual diagram showing a storage space of a display memory.

FIG. 5 is a conceptual diagram illustrating the operation of a selector.

FIG. 6 is a timing chart showing an operation when thinning in the horizontal and vertical directions is performed.

FIG. 7 is a timing chart showing an operation when thinning is performed only in the vertical direction.

FIG. 8 is a timing chart showing an operation when thinning is not performed in any of the horizontal direction and the vertical direction.

FIG. 9 is a block diagram illustrating a basic configuration of an ultrasonic diagnostic apparatus.

FIG. 10 is a diagram showing a configuration of a first conventional example.

FIG. 11 is a conceptual diagram showing the operation of the first conventional example.

FIG. 12 is a diagram showing a configuration of a second conventional example.

FIG. 13 is a conceptual diagram showing the operation of the second conventional example.

[Explanation of symbols]

34 display memory, 36 first plane, 38 second plane, 40 write controller, 42 read controller, 4
4 Write control circuit, 46 selector, 48 read control circuit, 50 selector, 52 control unit, 54 freeze switch, 56 mode selector.

Claims (4)

(57) [Claims] 1. An ultrasonic diagnostic apparatus capable of displaying N ultrasonic images side by side on the same screen, wherein the memory comprises N storage planes, each storage plane having a storage capacity of one frame. A display memory, writing control means for writing image data to any one of the storage planes in the single display mode, and writing image data of each ultrasonic image to each of the storage planes in the multiple display mode, and the display at the display timing of the display unit Reading control means for reading image data from a memory, reading image data from any of the storage planes in a single display mode, and reading out image data of each image from a plurality of storage planes in a multiple display mode, And the display memory has an address terminal for each same address.
A plurality of memory chips commonly connected to each other, the plurality of memory chips
Or display ads in order along at least one of the vertical
Address, and the read control unit controls the display mode and each of the supersonic
Depending on the image format of the wave image, the plurality of memory chips
Selector that selects image data output simultaneously from the
And the selection of image data by the chip selector
An ultrasonic diagnostic apparatus characterized in that image data is thinned out . 2. The apparatus according to claim 1, wherein the read control unit is configured to control image data in both a vertical direction and a horizontal direction when a two-dimensional sectional image is displayed in the multiple display mode. An ultrasonic diagnostic apparatus which performs thinning-out reading and performs thinning-out reading only in the vertical direction when an image in a sweep format in which horizontal sweeping is performed is displayed. 3. A device according to claim 1, storing said display displays image space on the memory is divided for each pixel block consisting of four pixels, the pixel data is the first memory chip of the top left pixel in each pixel block The pixel data of the upper right pixel in each pixel block is stored in the second memory chip, the pixel data of the lower left pixel in each pixel block is stored in the third memory chip, and the pixel of the lower right pixel in each pixel block An ultrasonic diagnostic apparatus wherein data is stored in a fourth memory chip. 4. The apparatus according to claim 3, wherein the pixel data is thinned out in both the horizontal direction and the vertical direction to reduce the ultrasonic image by a factor of four.
In the case where image data from only a specific one of the memory chips is used and the image data is thinned out only in the vertical direction to reduce the image vertically by half, An ultrasonic diagnostic apparatus, wherein image data from only the first and second memory chips or only the third and fourth memory chips is used.