JPH05293100A - Ultrasonic diagnostic apparatus - Google Patents

Abstract

PURPOSE:To provide an ultrasonic diagnostic apparatus which enables the reduction of fatigue of an eye of an operator to concentrate on the diagnosis by minimizing flickering on a screen in a type which has a transmitting/ receiving section to obtain echo information of a specimen and a digital scan converter to convert the echo information into an interlace TV signal to display an ultrasonic image on a monitor. CONSTITUTION:Circuitry is as illustrated. An even field and an odd field continuing are inputted simultaneously into two line memories 8 and 9 and video information is compressed to a double horizontal frequency with the above line memories 8 and 9. The information is outputted alternately at each scan line with an SW4 as switch to a double speed monitor 12.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic image display apparatus for displaying a tomographic image of a subject and other echo information by transmitting and receiving ultrasonic waves for diagnostic use.

[0002]

2. Description of the Related Art An ultrasonic diagnostic apparatus excites ultrasonic probes consisting of piezoelectric elements arranged in strips to generate ultrasonic waves,
The generated ultrasonic waves are transmitted to the subject, signal processing is performed based on the obtained echo information, and a tomographic image and blood flow information are displayed on the TV screen in real time. This ultrasonic diagnostic device is relatively easy and almost non-invasive,
Due to its high diagnostic ability, it has recently been used in many medical fields.

Here, the conventional ultrasonic diagnostic apparatus converts a received signal obtained by ultrasonic scanning into a digital signal by an A / D converter, and further converts this signal into a digital scan converter (hereinafter referred to as "DSC"). The scanning method and the timing are converted into a TV signal conforming to the broadcasting standard, and then the output of the DSC is converted into an analog TV signal by the D / A converter and displayed on the standard TV monitor.

[0004]

However, according to the conventional configuration, the TV conforming to the broadcasting standard such as NTSC or PAL is used.
It is displayed as a signal, and unlike an ordinary landscape image, the ultrasonic image has poor correlation between the front and back fields,
In the interlace scanning method, flicker due to different images in the first field and the second field becomes conspicuous,
Particularly in ultrasonic diagnosis, since the operator visually recognizes at a position close to the monitor screen, the operator suffers from eye fatigue, resulting in a reduction in image reading ability.

Therefore, as a method for solving the above problem,
A method of detecting a motion of an image and adaptively selecting several kinds of signal processing methods such as an EDTV system and performing a double speed conversion can be considered, but most of them are based on experimental data and experience. Since the method of recreating the signal is adopted, there are problems such as poor reproducibility in motion detection in images with little correlation, and it is difficult to accept in ultrasonic images that require faithful reproducibility. is there. further,
There is also a problem that the cost of the circuit for that is high.

In the real-time display method such as M mode or ECG, the horizontal direction of the image is the time axis and the temporal change of the ultrasonic image is displayed. However, the continuity of the information on the display screen in the time direction is considered. A so-called scroll display method in which an image continuously updated at the right end of the screen is sent to the left at a constant speed is generally accepted. In the case of this scroll display method, the image is a constant horizontal movement with various vertical movements added. The portion of the naked eye that has less movement has a characteristic of seeing more in detail, and when scrolling, the flicker of the TV becomes noticeable in the portion that has less vertical movement.
Therefore, it is desired to reduce flicker in order to further increase the resolution.

[0007]

In order to solve the above problems, the present invention is, firstly, a transmitting / receiving section for obtaining echo information of a subject and a digital scan converter for converting a received signal into an interlaced TV signal. And an ultrasonic diagnostic apparatus for displaying an ultrasonic image of a subject on a monitor, the two storage units capable of compressing the time axis of video information in half and converting the horizontal frequency to twice the horizontal frequency of the input signal for output. And a switch capable of outputting video information from the two storage units at a predetermined timing, and the monitor is operated at a horizontal frequency twice as high as that of a normal TV, and is sent from a digital scan converter. The video information of one of the even field and the odd field of the interlace is input to one storage unit and the other video information is input to the other storage unit at the same time.
It is characterized in that it is read out at a double horizontal frequency, is alternately output for each scanning line by the switching device, and is displayed on the monitor. Secondly, a transmitting / receiving unit for obtaining echo information of the subject. And an ultrasonic diagnostic apparatus that includes a digital scan converter that converts a received signal into an interlaced TV signal, and that simultaneously or selects a scroll image and a non-scroll image and displays an ultrasound image of a subject on a monitor. There are provided two storage units capable of compressing the time axis of the video information in half and converting the horizontal frequency to twice the horizontal frequency of the input signal for output, and a switching unit capable of outputting the video information from the two storage units at a predetermined timing. In addition, the above monitor is a normal TV
In the non-scroll image mode, the video information of one of even and odd fields of the interlace sent from the digital scan converter is stored in one storage unit and the other video information of the other is transmitted in the non-scroll image mode. To the storage unit at the same time, read out at the storage unit at a double horizontal frequency, output alternately for each scanning line by the switching unit, display on the monitor, and in the scroll image mode, from the digital scan converter. The field image information to be sent is input to one of the storage units, and the storage unit
It is characterized in that it is read at a double horizontal frequency, is alternately output by the switching device for each scanning line, and is displayed on the monitor.

Thirdly, it has a transmitting / receiving unit for obtaining echo information of the subject and a digital scan converter for converting the received signal into an interlaced TV signal, and the ECG, M
In an ultrasonic diagnostic device that can display the temporal change of the ultrasonic image on the monitor by setting the horizontal direction of the screen as the time axis, such as modes, compress the time axis of the video information in half and double the input signal. , Which has two storage units capable of being converted into the horizontal frequency and outputting the same, and a switcher capable of outputting the video information from the two storage units at a predetermined timing. It is assumed that the digital scan converter operates at the horizontal frequency, and the digital scan converter starts reading from the field memory according to the display area at a fixed memory address and moves one vertical line on the screen at a constant speed from left to right. , Even if the interlace sent from the digital scan converter has the function of performing the so-called moving bar method that displays updated information on the left side of the vertical line One of the video information of the field and the odd field is input to one storage unit and the other video information is input to the other storage unit at the same time, and the storage unit reads out at a double horizontal frequency. It is characterized in that the output is alternately output every time and the whole area of the display screen is set to the non-scroll image mode and displayed on the monitor.

[0009]

In the present invention, the video information of the even field and the video information of the odd field from the DSC are simultaneously input to the respective storage sections. Since the storage unit can compress the time axis of the video information in half and convert it into a horizontal frequency twice as high as the input signal and output it, the video information of each even field and odd field is doubled horizontally in the storage unit. It is compressed to a frequency, and this is output alternately for each scanning line by a switching device.
Since it is displayed on a monitor that operates at twice the horizontal frequency, an image with less flicker is displayed.

When the moving bar method is adopted, the display screen itself is a still image, so an image with little flicker is displayed.

[0011]

Embodiments of the present invention will be described with reference to the drawings.
In the ultrasonic diagnostic apparatus according to the present invention, as shown in FIG. 1, after the received signal obtained from the transmitting / receiving unit 21 by transmitting / receiving ultrasonic waves is converted into a digital signal by the A / D converter 1, the interlace is performed by the DSC 2. Convert to TV signal.
Here, in the conventional case, the output of the DSC 2 is the D / A converter 1
1 is converted into an analog TV signal and displayed on a standard TV monitor.

In the present invention, the above DSC2 and D / A
It is characterized in that a circuit surrounded by a broken line is provided between the converters 11.

That is, the DSC 2 is serially connected with field memories 3 and 4 for storing video information within a field period of a TV signal, and the field memories 3 and 4 are D
Writing and reading are updated in synchronization with the timing of the field frequency output from SC2. The DSC 2 has a function of dividing into a scroll image mode such as an M mode (hereinafter referred to as a scroll mode) and a non-scroll image mode such as a B mode (hereinafter referred to as a non-scroll mode) on the TV screen. Area settings such as upper and lower halves on the same screen are controlled by the scroll mode area gate signal.

The outputs of the field memory 3 are SW1 and SW.
2 to the line memory 8 and SW1 and SW3 to the line memory 9, and the field memory 4
Is configured to be input to the line memory 8 via SW2. The video signal from DSC2 is input to the line memory 9 via SW3. The line memories 8 and 9 have a function of compressing the time axis of the video signal in half and doubling the horizontal frequency of the input signal for output, and correspond to the storage section in the claims. The outputs of the line memories 8 and 9 are read by the SW 4 at a predetermined timing and input to the D / A converter 11. This SW4
Corresponds to the switch in the claims. Then, the video information converted into the analog information is sent to the double speed monitor 12. The double-speed monitor 12 is a double-speed monitor that operates at a horizontal frequency twice as high as that of a normal TV since the line memories 8 and 9 output at a horizontal frequency twice as described above. As will be described later, the brightness correction 13 is provided because brightness correction is required in the non-scroll mode area.

Here, SW1 is controlled by the gate signal from DSC2 which sets the scroll mode area, and falls to the GND side only in the scroll mode area.
Stop the video signal. SW2 and SW3 are controlled by the scroll mode gate signal and the even-odd signal. SW4 is controlled by a signal 2f _H from the DSC 2 having a frequency twice the horizontal scanning frequency.

The detailed configuration of the DSC 2 is as shown in FIG. 2, and the USDR (ULTRASOUND D
The video information input to ATA RECEIVER is
Once stored in MM (MASS MEMORY), SC
(SCAN CONVERTER) is basically converted to standard TV scanning and PSTP (POST PROC)
It is output after finishing into a TV signal by ESS). Even-odd signal, scroll area gate signal, and double frequency signal 2
f _H is TBG (TIME BASE GENERATE)
OR).

Next, the operating condition of the present invention will be described with reference to the timing chart shown in FIG.

In the case of a non-scroll image mode such as B mode, the following is performed. For example, when the DSC 2 outputs the second field, that is, when focusing on the third field from the left in the DSC output of FIG. 3, the field memory 3 outputs the first field immediately before that. In this case, since it is in the non-scroll mode, the switch is controlled so that the first field from the field memory 3 and the second field from the DSC 2 are simultaneously input to the line memory 8 and the line memory 9, respectively. That is,
If the output of DSC2 is an even field, DSC2
Of even fields and the odd field of the field memory 3 are output. In the line memories 8 and 9, the time axis of the video signal is compressed in half and output at the same time, and the signals are switched and output for each scanning line by the SW4. Therefore, "10. SW4 output (non-scroll mode area ) ”Is obtained. SW4
The video information output from is converted by the D / A converter 11 and displayed at double speed by the double speed monitor 12.

Next, when the DSC 2 outputs the fourth odd field from the left shown in FIG. 3, the switch is controlled so that the even field is transferred from the field memory 3 to the line memory 9 in almost the same manner as above. , An odd field from the field memory 4 is input to the line memory 8, and as a result, the same information as when the DSC 2 outputs the previous even field is input to each line memory and is output at a double horizontal frequency. It will be. That is, the same video information is output twice.

Since the horizontal frequency is doubled and displayed as described above, it is possible to obtain an ultrasonic diagnostic image in which flicker is suppressed.

Next, in the scroll mode such as the M mode, there is a motion of the video within one frame, and the image is blurred when the above signal processing is performed, so the following processing is performed. .. In other words, in the scroll image mode, SW1 falls to the GND side, so the line memory 8
The video information is input to one of the line memories 9 and not input to the other, and an output as shown in "10. SW4 output (scroll mode area)" in FIG. 3 is obtained. In this case, the black level (no signal) appears every other line and the entire image becomes dark, so the brightness correction is performed by the brightness correction 13. That is, the flicker is not improved in the scroll mode. Interpolation processing in the field like EDTV is also conceivable, but in the case of an image with low correlation such as an ultrasonic image, flicker is not improved so much because of blurring and deterioration of image information. It was adopted.

The state of the patterns before and after conversion in the line memory 8 and the line memory 9 is shown. In the non-scroll image mode, as shown in FIG. 4, the patterns in which the images of the first field and the second field overlap each other. Is obtained. The same pattern is 2
As shown above, two of the same video information are drawn.
This is because it is output and displayed once. In the scroll image mode, as shown on the right side of FIG. 5, a black level appears every other line, so the image becomes darker, and luminance correction is required.

The operation is the same as in the scroll mode for external input signals such as VTR. Further, when freeze is applied by the ultrasonic diagnostic apparatus, since it is a still image, the operation is in the non-scroll mode. Therefore, when an ultrasonic image that is normally used is frozen for measurement, the screen is easy to see without flicker, and the effect of the present invention is exhibited. Also in the color ultrasonic diagnostic apparatus, the same effect can be obtained by applying the present system in parallel for each of the three types of RGB.

Here, in the above-mentioned embodiment, the screen in which the non-scroll image and the scroll image are mixed in the upper and lower halves has been described. However, when the whole screen is in the non-scroll image mode, the flicker occurs on the entire screen. You can get an ultrasonic screen without.

The following embodiment solves the problem that flicker cannot be improved in the scroll mode in the above embodiment. The feature of this embodiment is that the real-time display system is used. As a result, the moving bar method was adopted.

That is, in the scroll method, as shown in FIG. 6, information that is continuously updated in real time at the right end of the screen is flowed at a constant speed to the left for a certain section, as if the scroll on the screen is viewed. In contrast to the method of observing information over time, the moving bar method moves one vertical line on the screen from left to right at a constant speed and displays updated information on the left side of the vertical line. .. In the digital scan converter used in the ultrasonic diagnostic apparatus, the field memory information corresponding to the display area is updated in the continuous time phase. The difference between the two methods is that in the scroll method, as shown in FIG. Shows that the memory addresses at the beginning of writing and at the beginning of reading shift together with the movement of scrolling, whereas in the case of the moving bar method, as shown in FIG. However, the only difference is that the memory address is always shifted to a constant memory address at the beginning of reading.

The configuration according to this embodiment is almost the same as that of the above-described embodiment as shown in FIG. 9, and the received signal is converted from analog to digital by the A / D converter 1 and then by the DSC 2. Convert to TV signal. The field memories 3 and 4 are delayed by one field, and the multiplexer 14 inputs the field information to the line memories 8 and 9 in accordance with the even / odd signal of the field. Although the multiplexer 14 is used in this embodiment, it is functionally the same as the switch group used in the above embodiment. That is, as shown in FIG. 10, when the DSC 2 outputs an even field, the odd field of the field memory 3 is input to the line memory 8 and the even field of the DSC 2 is input to the line memory 9, while the DSC 2 outputs an odd field. When outputting a field, the field memory 4
The odd fields of 1 are input to the line memory 8, and the even fields of the field memory 3 are input to the line memory 9.
A TV signal is output at a double horizontal frequency in the line memories 8 and 9, and the output is switched by the SW4 to be converted into a non-interlaced TV signal by the D / A converter 11 and displayed on the double speed monitor 12.

FIG. 11 shows the state of the patterns before and after the conversion of the line memories 8 and 9, and the display screen observed by the operator is always a still image. Therefore, the simple circuit as described above is used. An image with less flicker can be obtained. However, according to the format of this embodiment, the images are discontinuous on the left and right sides of the moving bar, and continuous image information as in the scroll method cannot be obtained. However, if the display screen is frozen and the read address of the memory is intentionally changed to move the bar to the right end of the image area, it is possible to display an image equivalent to that at the time of scrolling. Note that this embodiment can be applied to a color ultrasonic diagnostic apparatus by adopting this method in parallel for each of the three types of RGB, as in the above-described embodiments.

[0029]

As described above, the present invention is configured as described above and compresses and displays the video information at the double horizontal frequency. Therefore, it is possible to provide an ultrasonic diagnostic image with suppressed flicker and the operator's eyes. It can reduce fatigue and focus on diagnosis. Further, even when the ultrasonic image is frozen, the image does not flicker and the measurement can be performed accurately.
In the present invention, since no correction is added to the image information, there is no adverse effect on the ultrasonic image quality such as deterioration or loss of the image information. Further, when the moving bar method is adopted, the entire screen becomes a still image, so that an image without flicker can be obtained.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing a configuration of the present invention.

FIG. 2 is a block diagram illustrating the DSC in FIG. 1 in detail.

FIG. 3 is a timing chart showing an operation state of the present invention.

FIG. 4 is an explanatory diagram showing a state of image information before and after conversion by a line memory in a non-scroll image mode area.

FIG. 5 is an explanatory diagram showing a state of line memory in a scroll image mode area and image information before and after conversion.

FIG. 6 is an explanatory diagram showing a scroll method and a moving bar method.

FIG. 7 is an explanatory diagram showing write and read operations in a field memory in a digital scan converter in a scroll system.

FIG. 8 is an explanatory diagram showing write and read operations in a field memory in a digital scan converter in the case of a moving bar method.

FIG. 9 is a circuit diagram showing a configuration of the present invention.

FIG. 10 is a timing chart showing an operation state of the present invention.

FIG. 11 is an explanatory diagram showing a state of image information before and after conversion in a line memory and a switch when a moving bar method is adopted.

[Explanation of Codes] 1 A / D converter 2 DSC 3, 4 field memory 5 SW1 6 SW2 7 SW3 8, 9 line memory 10 SW4 11 D / A converter 12 double speed monitor 14 multiplexer 21 transceiver unit

Claims (3)

[Claims] 1. A transmission / reception unit for obtaining echo information of a subject,
In an ultrasonic diagnostic apparatus having a digital scan converter for converting the echo information into an interlaced TV signal and displaying an ultrasonic image of a subject on a monitor, the time axis of the video information is compressed in half and input signal 2 It has two storage sections that can be converted into a double horizontal frequency and then output it, and a switcher that can output the video information from the two storage sections at a predetermined timing. The video data of one of the even and odd fields of the interlace sent from the digital scan converter is input to one storage unit and the other video information is input to the other storage unit at the same time. Read out at double horizontal frequency in memory,
An ultrasonic diagnostic apparatus characterized in that the switching device alternately outputs each scanning line and displays on the monitor. 2. A transmitting / receiving unit for obtaining echo information of a subject,
An ultrasonic diagnostic apparatus having a digital scan converter for converting the echo information into an interlaced TV signal and displaying an ultrasonic image of a subject on a monitor at the same time or by selecting a scroll image and a non-scroll image. It has two storage sections that can compress the time axis of information in half and convert it into a horizontal frequency that is twice that of the input signal and output it, and a switcher that can output the video information from the two storage sections at a predetermined timing. In addition, it is assumed that the monitor operates at a horizontal frequency twice as high as that of a normal TV, and in the non-scroll image mode, the video information of one of the even field and odd field of the interlace sent from the digital scan converter is To the other storage unit at the same time, and the other storage unit reads the video information at the double horizontal frequency, In the scroll image mode, the field image information sent from the digital scan converter is input to any one of the storage units, and is output to each of the storage units. An ultrasonic diagnostic apparatus characterized in that it is read at a double horizontal frequency, is alternately output for each scanning line by the switching device, and is displayed on the monitor. 3. A transmitting / receiving unit for obtaining echo information of a subject,
It has a digital scan converter for converting the echo information into an interlaced TV signal, and is capable of displaying a time change of an ultrasonic image on a monitor by taking a time axis on the screen like M mode and ECG. In a sonic diagnostic apparatus, two storage units capable of compressing the time axis of video information in half and converting it to a horizontal frequency twice the input signal and outputting the same, and outputting the video information from the two storage units at a predetermined timing. And a monitor capable of operating at a horizontal frequency twice as high as that of a normal TV. Further, the digital scan converter has a fixed memory address for reading from the field memory according to the display area. Beginning with the above, a so-called movie that moves one vertical line on the screen from left to right at a constant speed and displays updated information on the left side of the vertical line. Having the function of performing a ngbar system, inputting one video information of one of the even field and odd field of the interlace sent from the digital scan converter to one storage unit and the other video information to the other storage unit at the same time. Read out at double horizontal frequency in memory,
An ultrasonic diagnostic apparatus characterized in that the switching device alternately outputs each scanning line to display the entire area of the display screen in a non-scroll image mode on the monitor.