JPH0595944A - Ultrasonic diagnostic apparatus - Google Patents

Abstract

PURPOSE:To achieve higher operability along with a low cost by minimizing the capacity of a software concerning an interpolation circuit. CONSTITUTION:X and Y addresses are generated with address generators 4 and 5 for an echo signal detected with a probe to be written into a writing address memory 6. Then, a writing end control section 7 determines a difference between the preceding and present X address values at each Y address of a scan line. When the difference exceeds a limit value preset, the writing into an image memory 1 is stopped with an image memory writing control section 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic diagnostic apparatus using a probe having a fan-shaped mapping such as a convex or sector probe.

[0002]

2. Description of the Related Art In an ultrasonic diagnostic apparatus using a probe having a fan-shaped mapping such as a convex or sector probe, the intervals between adjacent scan line images become wider as the distance from the probe increases, and the pixels between them become missing in the image data. become. Therefore, these vacant pixels are interpolated based on the adjacent image data to form an easy-to-see image.

FIG. 4 is a digital scan converter (hereinafter referred to as DSC) in a conventional ultrasonic diagnostic apparatus.
Shows a part of. The echo signal received by the probe is A
After being D-converted, it is once written in a line memory (not shown), then read as echo data and sent to the image memory 1. Further, the mapping address generation circuit 2 sequentially calculates the addresses corresponding to the echo data and sends them to the image memory 1.

In the image memory 1, the input echo data is written to a designated address, and the echo data is read out in the order of addresses at a predetermined timing and sent to the interpolation circuit 3. The interpolator 3 interpolates an address at which actual image data is not sent, that is, a pixel at a position not detected by the probe, from the actual data of the adjacent pixel from the value of the echo data sent in the order of address To do. The interpolated image data is sent to a DA converter (not shown) and displayed on a monitor screen such as a CRT.

FIG. 2 shows the structure of a scan line image to be displayed. In the case of a probe having a fan-shaped mapping such as a convex probe or a sector probe, a scan line image radiating downward from the probe portion is formed. Figure 3
2 is an enlarged view of a part of FIG. The intersection of the grid is a unit pixel, and the continuous pixels indicated by black circles and white circles are images of a series of scan lines. When this image is written in the image memory 1, it is written in the y-axis direction from above in the order of generation of echo data from the probe section. If the screen is displayed, x
Reading is performed in order from the top along the axial direction.

The intersections of the grids in the figure which are neither black circles nor white circles are empty pixels in which no image data is written. The vacant pixel is interpolated in the interpolation circuit 3 by the average value of black circles and white circles located before and after the screen scan direction parallel to the x axis.

[0007]

By the way, in the above-mentioned ultrasonic diagnostic apparatus, since the scan line image is displayed as a fan-shaped mapping, the distance between the scan line images increases as the distance from the probe increases, and the number of empty pixels in the meantime is increased. Will increase. However, the normal interpolation circuit 3
When the number of empty pixels is increased, the image data values in the meantime are not interpolated indefinitely, so that interpolation is not possible for a certain number or more of empty pixels.

Therefore, in the actual ultrasonic diagnostic apparatus, when the display screen is scrolled to display the lower screen, the number of empty pixels in the pixel data read from the image memory 1 is set in advance. If the limit value is exceeded, the operation of the interpolator 3 is restricted and it does not operate normally, which may lead to malfunction. Therefore, in order to keep the operation of the apparatus normal, a method of individually limiting the scroll amount of the screen or limiting the image processing depending on the type of diagnostic probe, the display magnification, and the like is adopted.

As described above, in the conventional apparatus, various kinds of software must be prepared and dealt with according to the configuration conditions and combinations of the apparatuses, and there is a problem that the software becomes large-scale. . The present invention has been made to solve the above problems, and an object thereof is to provide an ultrasonic diagnostic apparatus that is inexpensive and easy to use, while minimizing the scale of software related to an interpolation circuit. is there.

[0010]

In order to achieve the above object, the present invention converts an echo signal detected by a probe into a scan line image of a fan-shaped image by a digital scan converter having an interpolation circuit and displays it. In the ultrasonic diagnostic apparatus, means for calculating the number of empty pixels in the x-axis direction between adjacent scan line images, and scan line data to the image memory when the number of empty pixels exceeds a preset limit value. And means for stopping the writing of data.

[0011]

In the present invention, when the echo signal detected by the probe is converted into a scan line image by the DSC, the number of empty pixels in the x-axis direction between adjacent scan line images is calculated, and the empty pixel is calculated. When the number exceeds a preset limit value, writing of scan line data to the image memory is stopped.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing the configuration of a mapping address generating circuit of an ultrasonic diagnostic apparatus according to the present invention. Mapping data, a clock, and the like are input to the mapping address generation circuit 2. These signals are sent to the X address generator 4, the Y address generator 5 and the image memory write control unit 8, respectively.

The X address generator 4 and the Y address generator 5 generate an image based on the mapping data and the clock while the write end signal from the write end control unit 7, which is the empty pixel number calculating means, is off. Memory 1
To generate the X and Y addresses of the image memory 1, the write address memory 6, and the write end control unit 7.
Send to. The X and Y addresses are the X and Y addresses on the image memory 1 in which the scan line data is written in pixel units, and each pixel when the scan line image is displayed as a bitmap on a screen such as a CRT monitor. It is also the X and Y coordinates of.

The write address memory 6 sends X and Y addresses for each scan line until the control signal for instructing the end of writing is sent from the image memory writing controller 8 which is a writing stop means. Then, based on the Y address, the X address is written line by line. That is, for each Y address, the Y
The X address corresponding to each line is sequentially written in the address. When the X and Y addresses are input to the write address memory 6, if the X address of the previously input line has already been written for the input Y address, the value of the previous X address is used for the write end control. It is output to the unit 7.

When the X and Y addresses are input, the write end control unit 7 obtains the difference between the X address value of this time and the previous X address value output from the memory 6 for the Y address. Here, the obtained difference is the number of empty pixels, and when the number of empty pixels exceeds the maximum interpolable pixel number of the interpolation circuit 3, the write end signal is sent to the address generators 4 and 5 and the image memory write control. Send to Part 8. The maximum number of interpolable pixels is a value preset for each device, and is generally set to 16 pixels in many cases.

When the writing end signal is input, the image memory writing control section 8 sends a control signal instructing the end of writing to the writing address memory 6 and the image memory 1 based on the clock timing. Although not shown in FIG. 1, the image memory 1 is similar to FIG.
The echo signal detected by the fan-shaped image type probe connected to the mapping address generation circuit 2 is
Image memory 1 converted to scan line image by C
Are written into the monitor screen, and the vacant pixels are interpolated through the interpolation circuit 3 and then displayed on the monitor screen.

As described above, the mapping address generating circuit 2 according to the embodiment is provided with the write address memory 6 and calculates the X coordinate interval at the same Y coordinate for each displayed scan line image as the number of empty pixels. When the number of empty pixels exceeds the maximum number of interpolable pixels of the interpolation circuit 3, writing to the image memory 1 and the write address memory 6 is stopped.

That is, when the lower end of the scan line image is displayed on the screen by scrolling the image, the number of empty pixels gradually increases, and when the maximum interpolable pixel number of the interpolation circuit 3 is exceeded, mapping is performed. The address generation circuit 2 will stop scrolling. As a result, it is possible to prevent the occurrence of a malfunction due to the image data having an excessively large number of empty pixels being written in the image memory 1 and further being sent to the interpolation circuit 3. Further, as a result, the operational limitation that has been conventionally required depending on the diagnostic probe, the display magnification, etc. is not required, and the scale of the software is correspondingly reduced and the cost is reduced.

[0019]

As described above, according to the present invention, when the number of empty pixels in the x-axis direction of adjacent scan line images exceeds a preset limit value, the scan line data in the image memory is By stopping the writing, the operation of the interpolation circuit can be normally maintained even if the number of empty pixels is large. As a result, the software related to the interpolation circuit of the ultrasonic diagnostic apparatus is minimized, the cost is reduced, and the usability is improved.

[Brief description of drawings]

FIG. 1 is a block diagram showing a main part of an embodiment of the present invention.

FIG. 2 is a diagram showing a configuration of a displayed scan line image.

FIG. 3 is an enlarged view of a part of FIG.

FIG. 4 is a block diagram showing a part of DSC in the ultrasonic diagnostic apparatus.

[Explanation of symbols]

 1 Image Memory 2 Mapping Address Generation Circuit 3 Interpolation Circuit 4 X Address Generator 5 Y Address Generator 6 Write Address Memory 7 Write End Control Section 8 Image Memory Write Control Section

Claims (1)

[Claims] 1. An ultrasonic diagnostic apparatus for converting an echo signal detected by a probe into a scan line image of a fan-shaped image by a digital scan converter equipped with an interpolation circuit and displaying the scan line image. A means for calculating the number of free pixels in the direction, and a means for stopping the writing of scan line data to the image memory when the number of free pixels exceeds a preset limit value. Ultrasonic diagnostic device.