JPH05329161A - Ultrasonic diagnostic system - Google Patents

Abstract

(57) [Summary] [Object] An object of the present invention is to reduce the capacity of a memory for storing a reproduced image without deteriorating the image quality of the image displayed in real time. [Structure] When an ultrasonic image is displayed in real time, the signal detected by the probe 11 is an A / D for image signal.
The converter 12 converts the signal into a digital signal (for example, 8 bits), and the scanning converter 13 and the video signal D / A converter 15 perform scanning direction conversion and D / A conversion, which are displayed on the display device 16. .. When reproducing a recorded ultrasonic image, the analog video signal output from the VTR 17 has a smaller number of bits (for example, 5 bits) than that of the image signal A / D converter 12 for reproduction video A / D conversion. It is converted into a digital reproduction video signal by the device 18 and sequentially written in the reproduction video memory 19. Then, the switcher 14 adds 3-bit predetermined data to the 5-bit digital reproduction video signal read from the reproduction video memory 19, and the data is displayed on the display device 16 via the video signal D / A converter 15. It

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 for irradiating a subject with an ultrasonic signal and detecting a signal reflected from the subject to obtain an internal tomographic image or the like.

[0002]

2. Description of the Related Art An ultrasonic diagnostic apparatus is widely used because it can obtain a tomographic image of the inside of a human body without affecting the human body.

Some ultrasonic diagnostic apparatuses are capable of displaying an ultrasonic image in real time, recording an analog image displayed on a display unit in a recording device, and reproducing the recorded image. ..

In recent ultrasonic diagnostic apparatuses, digital signal processing is performed with a high bit width in order to improve the image quality of an image, and in a color Doppler apparatus for displaying a color image, the bit width of a video signal is much larger. Is becoming

[0005]

In an apparatus having a recording / playback function for ultrasonic images, as the bit width of the video signal increases as described above, the memory capacity of the video memory for recording the ultrasonic image increases accordingly. There was a problem that the cost would increase.

An object of the present invention is to reduce the capacity of the memory for storing reproduced images without deteriorating the image quality of images displayed in real time.

[0007]

FIG. 1 is a block diagram showing the principle of the first invention. An ultrasonic diagnostic apparatus having a function of irradiating a subject with ultrasonic waves, detecting a signal reflected from the subject, displaying an ultrasonic image, and recording the ultrasonic image in a recording device (8). The first A / D conversion means 1 converts an analog signal reflected from the subject into a digital signal.

The scanning conversion means 2 converts the scanning direction of the digital signal. The scan conversion means 2 converts a digital signal obtained by, for example, ultrasonic scanning into a TV scanning signal.

The second A / D conversion means 3 converts the analog reproduction video signal output from the recording device 8 during reproduction into a digital reproduction video signal with a bit number smaller than that of the first A / D conversion means 1. To do.

The reproduced video storage means 4 stores the digital reproduced video signal converted by the second A / D conversion means 3. The switching means 5 selects and outputs one of the digital video signal output from the scan conversion means 2 and the digital playback video signal output from the playback video storage means 4.

The video signal D / A conversion means 6 converts the digital video signal selected by the switching means 5 into an analog video signal. The display means 7 displays the analog video signal.

FIG. 2 is a block diagram showing the principle of the second invention. In the figure, the reproduction signal processing means 9 converts the signal reflected from the subject into an analog signal representing the Doppler shift amount.

The first A / D conversion means 1a converts the analog signal representing the Doppler shift amount into a digital signal. Hereinafter, the scan conversion means 2a, the second A / D conversion means 3a, the reproduced video storage means 4a, the switching means 5a, the video signal D / A conversion means 6a, and the display means 7 are the same as those of the first invention. It has a similar function.

[0014]

When the ultrasonic image is displayed in real time, the digital video signal output from the scanning conversion means 2 is selected by the switching means 5 and converted into an analog video signal by the video signal D / A conversion means 6. It is displayed on the display unit 7. The real-time ultrasonic image is recorded in the recording device 8.

When reproducing a recorded ultrasonic image, the analog reproduction video signal output from the recording device 8 is converted into a digital reproduction video signal by the second A / D conversion means 3, and the digital reproduction video signal is reproduced. The signal is stored in the reproduced video storage means 4.

At this time, since the number of conversion bits of the second A / D conversion means 3 is made smaller than that of the first A / D conversion means 1, the ultrasonic image displayed in real time is directly displayed. The amount of data to be stored is smaller than that in the case of storing, and the storage capacity of the reproduced video storage means 4 can be reduced.

In the second invention, the signal processing means 9 converts the reflected signal from the subject into a signal representing the Doppler shift amount, and the first A / D converting means 1a converts the signal into a digital signal. There is.

Therefore, in the ultrasonic diagnostic apparatus capable of displaying the distribution of blood flow and the like, by making the number of bits of the second A / D conversion means 3a smaller than that of the first A / D conversion means 1a, The same effect as the first invention can be obtained.

The recording device 8 may be built in the ultrasonic diagnostic device or may be provided separately from the ultrasonic diagnostic device.

[0020]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 3 is a configuration diagram of the ultrasonic diagnostic apparatus of the first embodiment.

In the figure, the probe 11 is composed of a large number of ultrasonic transducers, and radiates ultrasonic waves to detect echoes reflected inside the human body. The analog signal detected by the probe 11 is converted into a digital image signal by the image signal A / D converter 12. Further, the scan converter 13 performs scan conversion for displaying the digital image signal obtained by scanning the ultrasonic beam on a display device such as a CRT.

The switching device 14 is a circuit for selecting and outputting one of the output signals of the scan converter 13 and a reproduction video memory 19 which will be described later. In the case of displaying an ultrasonic image in real time, the switching device 14 performs scanning. The digital video signal output from the converter 13 is selected and output to the video signal D / A converter 15, and at the time of VTR reproduction, the digital reproduction video signal output from the reproduction image memory 19 is converted into a 3-bit digital signal. The signal is added and output to the video signal D / A converter 15.

The video signal D / A converter 15 converts a digital video signal (including a digital reproduction video signal) selected and output from the switcher 14 into an analog video signal and displays it on a display device 16 such as a CRT. Output and display as an ultrasonic image. The analog video signal displayed on the display device 16 is simultaneously recorded in the VTR 17.

When there is a reproduction instruction, the analog video signal recorded in the VTR 17 is reproduced video A / D converter 1
8 and is converted into a digital reproduced video signal in the reproduced video A / D converter 18.

Since the image quality of the VTR recorded image is lower than that of the image displayed in real time, the bit width in the case of A / D conversion of the reproduced image is displayed in real time in this embodiment. Have less.

For example, an image signal A / D for converting an analog image signal from the probe 11 into a digital image signal.
The converter 12 is composed of an 8-bit A / D converter, and a VTR
The reproduced video A / D converter 18 for converting the analog reproduced video signal output from 12 into a digital reproduced video signal is composed of a 5-bit A / D converter.

The playback video memory 19 is used for playback video A /
This is a memory for storing the digital reproduction video signal output from the D converter 18 in units of 5 bits, and outputs the stored digital reproduction video signal to the switcher 14.

It should be noted that the reproduced image is once reproduced in the video memory 1 for reproduction.
By storing it in 9, it is possible to improve the image quality when displaying a still image and the like, and it is possible to perform digital processing on the reproduced image.

As shown in FIG. 4, the switch 14 has two 8-bit input ports and one 8-bit output port, and one of the input ports is switched in accordance with the VTR reproduction switching signal input to the selector terminal. Select and output the signal.

While the digital reproduction video signal output from the reproduction video memory 19 is 5 bits,
Since the bit number of the video signal D / A converter 15 is 8 bits, the third bit (3B) of the lower 3 bits of the input port to which the digital reproduction video signal is input is set to "1" inside the switcher 14. The second bit (2B) and the first bit (1B) are set to "0". By doing so, the difference in brightness between the image before recording and the reproduced image can be reduced.

As described above, the bit number of the digital reproduction video signal is made smaller than the bit number of the real-time image, so that the data amount of the image data to be stored in the reproduction video memory 19 is reduced and the memory capacity of the reproduction video memory 19 is reduced. Can be reduced.

Next, an embodiment of the color Doppler device will be described with reference to FIG. The color Doppler device is a device for displaying a two-dimensional distribution of blood flow in color on a B-mode image and an M-mode image of an ultrasonic wave in real time.

Probe 3 comprising a Doppler probe or the like
The signal detected by 1 is converted into a shift signal representing the Doppler shift amount in the analog signal processing unit 32, and further converted into a digital signal in the A / D converter 33 for Doppler signal.

The digital signal is frequency-analyzed by the digital signal processing section 34 and converted into three kinds of R, G, B digital color signals. The scan converter 35, the switch 36, and the video signal D / A converter 37 are circuits similar to the circuit blocks of the ultrasonic diagnostic apparatus described above.
Three circuits are provided for each of the three types of G and B signals.

The scanning converter 35 converts the ultrasonic scanning signal into a TV signal.
The R, G, and B signals converted into scanning signals are sent to the switch 3
After passing through 6, the video signal D / A converter 37 converts the analog video signal into an analog video signal, which is displayed on the display device 3 as an ultrasonic image.
8 is displayed.

The encoder 39 is a circuit that converts the analog RGB signal output from the video signal D / A converter 37 into a composite signal and outputs the composite signal to the VTR 40. The decoder 41 is a circuit that converts a composite signal output from the VTR 40 into an analog RGB signal during reproduction.

Analog R converted by this decoder 41
The GB signal is converted into a digital RGB signal by the reproduction video A / D converter 42 provided for three circuits of R, G, and B, and stored in the reproduction video memory 43 similarly provided for three circuits. To be done.

In this embodiment, the reproduced video A / D converter 4 is used.
The bit number of 2 is 5 bits, the bit number of the Doppler signal A / D converter 33 is 8 bits, and the conversion bit number of the reproduced video A / D converter 42 is the Doppler signal A / D converter 3
Since the number of converted bits is smaller than 3, the data amount of the three types of digital reproduction video signals of R, G, and B to be stored in the reproduction video memory 43 is stored as a real-time image as a digital image. Compared to this, the memory capacity of the reproduction video memory 43 can be reduced.

[0039]

According to the present invention, for example, the number of bits of the reproducing A / D converter for converting an image recorded in the recording device into a digital signal is made smaller than the number of bits of the digital signal of the image displayed in real time. Thus, it is possible to reduce the memory capacity of the video memory for storing the reproduced image without deteriorating the image quality of the real-time image.

[Brief description of drawings]

FIG. 1 is a principle block diagram of a first invention.

FIG. 2 is a principle block diagram of a second invention.

FIG. 3 is a configuration diagram of the ultrasonic diagnostic apparatus of the first embodiment.

FIG. 4 is a configuration diagram of a switch.

FIG. 5 is a configuration diagram of a color Doppler device according to a second embodiment.

[Explanation of symbols]

 1, 1a First A / D conversion means 2, 2a Scan conversion means 3, 3a Second A / D conversion means 4, 4a Reproduced video storage means 5, 5a Switching means 6, 6a Video signal D / A conversion Means 7, 7a Display means 8 Recording device 9 Signal processing means

Claims (2)

[Claims] 1. A function of irradiating a subject with ultrasonic waves, detecting a signal reflected from the subject to display an ultrasonic image, and recording the ultrasonic image in a recording device (8). In the ultrasonic diagnostic apparatus, a first A / D conversion means (1) for converting an analog signal reflected from the subject into a digital signal, and output from the first A / D conversion means (1). Scan conversion means (2) for converting the scanning direction of a digital signal, and an analog reproduction video signal output from the recording device (8) at the time of reproduction with a smaller number of bits than the first A / D conversion means (1). Second A / D conversion means (3) for converting into a digital reproduction video signal, and reproduction video storage means (4) for storing the digital reproduction video signal converted by the second A / D conversion means (3). And the scan conversion means ( ), And a switching means (5) for selecting and outputting one of the digital video signal output from the digital video signal output from the reproduction video storage means (4) and the switching means (5). An ultrasonic diagnostic apparatus comprising: a video signal D / A conversion means (6) for converting a digital video signal into an analog video signal; and a display means (7) for displaying the analog video signal. 2. A function of irradiating a subject with ultrasonic waves, detecting a signal reflected from the subject to display an ultrasonic image, and recording the ultrasonic image in a recording device (8). In the ultrasonic diagnostic apparatus, signal processing means (9) for converting an analog signal reflected from the subject into an analog signal representing a Doppler shift amount, and an analog signal obtained by this signal processing means (9) is converted into a digital signal. First A / D conversion means (1a) for conversion
And a scanning conversion means (2a) for converting the scanning direction of the digital signal output from the first A / D conversion means (1a).
And a second one for converting an analog reproduction video signal output from the recording device (8) during reproduction into a digital reproduction video signal with a smaller number of bits than the first A / D conversion means (1a).
A / D conversion means (3a) and reproduction video storage means (4a) for storing the digital reproduction video signal converted by the second A / D conversion means (3a).
And a switching means (5a) for selecting and outputting one of the digital video signal output from the scan conversion means (2a) and the digital playback video signal output from the playback video storage means (4a). A video signal D / A conversion means (6a) for converting the digital video signal selected by the switching means (5a) into an analog video signal, and a display means (7a) for displaying the analog video signal. And ultrasonic diagnostic equipment.