JPH0218095B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an ultrasonic scanning method for an ultrasonic diagnostic apparatus.

Conventionally, the general block configuration of an ultrasonic diagnostic apparatus using a general NTSC television receiver for image display is as shown in FIG. In FIG. 1, a wave transmitting/receiving circuit 1 irradiates ultrasonic pulses toward an object to be diagnosed 2 such as a human body, receives the reflected waves reflected inside the human body, and receives analog echo signals (reflected wave signals). ). Digital scan
The converter 3 converts this echo signal into a digital quantity and stores it in its own frame memory, reads data from this frame memory in a signal format compatible with the standard NTSC television system, and
This is sent to the television receiver 4.

Such conventional digital scan converters are configured to read and write to the frame memory at the same time, so the control circuit for reading and writing is complicated, and furthermore, the control circuit for reading and writing is complicated. Memories called line buffers for temporarily storing data in order to adjust timing are required before and after the frame memory, which hinders miniaturization and cost reduction of the device.

The present invention eliminates the above-mentioned drawbacks of conventional devices, and eliminates the need for line buffers and complicated control circuits required in conventional digital scan converters, thereby making the device compact and inexpensive. The purpose of this invention is to provide a scanning method for a sound wave diagnostic device.

A feature of the present invention is that data is read from the frame memory during the time when the diagnostic image is displayed on the television image, and when the horizontal scanning line is blanked, the transceiver circuit uses a The present invention is configured to transmit and receive sound wave pulses and to write echo signals obtained from the wave transmitting and receiving circuit into a frame memory.

Hereinafter, the present invention will be explained based on the drawings.

FIG. 2 is a diagram showing the signal format of a video signal output from an ultrasonic device implementing the method of the present invention. NTSC television receivers, which are used to display images, use an interlaced system, with 525 horizontal scanning lines forming one frame, and each frame is divided into two fields: a first field and a second field. Of these 525 horizontal scanning lines, 232 horizontal scanning lines are actually used to display the diagnostic image, and these 232 horizontal scanning lines are indicated by diagonal lines in Figure 1. , 116 lines are assigned to each of the first and second fields, and blanking is performed on the remaining 293 horizontal scanning lines.

The analog echo signal output from the ultrasonic pulse transmitter/receiver circuit is temporarily stored in the frame memory in the digital scan converter, and read out from this frame memory in a signal format compliant with the NTSC standard television system. and sent to a television receiver.

In the method of the present invention, the diagnostic image is displayed as an image.
During the scanning time of 232 horizontal scanning lines, data is read from the frame memory, and during the scanning time of 293 horizontal scanning lines during which blanking is performed, ultrasonic pulses are transmitted and received by the transmitter/receiver circuit and data is read from the frame memory. data is written. That is, in FIG. 2, data is read from the frame memory in the shaded areas of the first and second fields where the diagnostic image is displayed. On the other hand, during the scanning period during which blanking is performed, the wave transmitting/receiving circuit transmits and receives ultrasonic pulses, and the obtained echo signals are sequentially written into the frame memory. One horizontal scanning time on a TV screen, or 1H, is approximately 63.55μs, and the time required to send and receive one ultrasonic pulse is
4H≒254μs. For this reason, ultrasonic waves are transmitted and received 36 times during the scanning line blanking time (146H or 147H), the obtained data is written into the frame memory, and the image is displayed in the next hatched area (116H). The operation of transmitting and receiving ultrasonic waves 36 times is repeated during the next blanking time.

If the write/read operations of the frame memory and the wave transmitting/receiving operations of the wave transmitting/receiving circuit are performed at the above-mentioned timings, the echo signal obtained from the wave transmitting/receiving circuit can be used for timing adjustment when writing to the frame memory. A hot line/buffer becomes unnecessary.

Figure 3 shows a digital computer that implements the method of the present invention.
FIG. 2 is a block configuration diagram of a scan converter.

In FIG. 3, an analog echo signal input from the wave transmitting/receiving circuit is converted into an analog/digital converter (hereinafter referred to as "A/D converter") 31.
After the bit digital signal is converted, it is input to frame memories 32A and 32B. The data read from the frame memories 32A and 32B are transferred to the latches 33 and 34 and the multiplexer 3.
A digital/analog converter (hereinafter referred to as "D/A converter") for video signals via 5 and 37.
38, and is sent from this D/A converter 38 to a television receiver as an analog video signal.

The addresses of the memories 32A and 32B are generated by a read address timing generator 39 and a write address timing generator 40. The generator 39 generates an address and a blanking (BLK) signal when reading from the memories 32A and 32B,
The generator 40 generates an RS signal indicating that reading is in progress, and generates an address when writing to the memories 32A, 32B and a WS signal indicating that writing is in progress. Address lines a ₀ to _{a 14} are connected to the generators 39 and 40, and these address lines
a ₀ to _{a 14} are connected to an address bus 41, and from this address bus 41 an address line is sent as an address in the depth direction of the ultrasonic sound rays of the memories 32a and 32B.
a ₀ to a ₇ , and the address in the ultrasonic beam scanning direction and address lines a ₉ to a ₁₄ to the memories 32A and 3, respectively.
Lead to 2B.

The TV sync generator 46 generates horizontal and vertical sync signals and field index (FI) signals (first and second fields) required for the NTSC standard television system.
This circuit generates field display signals), composite synchronization signals, etc. The timing generator 47 is a circuit that generates control signals such as X-position and Y-position synchronization signals to be sent to the wave transmitting/receiving circuit and trigger signals for the ultrasonic pulse generator.

Note that the adder 36, +1 circuit 42, gate 43,
44, 45, etc. are circuits for interpolating horizontal scanning lines for displaying diagnostic images on the television screen. In addition, this device performs writing/reading operations to the frame memory and horizontal scanning of the television receiver so that the scanning direction of the horizontal scanning line on the television screen matches the depth direction of the ultrasonic sound beam. It is configured as follows.

To explain the operation of this digital scan converter, in the shaded area (116H) of the first field in FIG.
Data is read from the D/A converter 3.
8, where it is converted into an analog signal and then sent to a television receiver for video display. At the same time, data is also read in the shaded area (116H) of the second field, but in this case, the adder 3
6, +1 circuit 42 operates to generate a signal for interpolating the horizontal scanning line drawn in the first field, and this signal is sent to the television receiver via the D/A converter 36.

Next, during the blanking time of the first and second fields, the wave transmitting/receiving circuit is activated by the control signal sent from the timing generator 47, and the echo signal obtained by the wave transmitting/receiving circuit is transmitted to the A/D converter 31. is input. This echo signal is sent to the A/D converter 31
is converted into a digital quantity and input into the frame memories 32A, 32B, and sequentially written to the addresses indicated by the generator 39.

In the above explanation, the number of horizontal scanning lines for displaying the diagnostic image is 232, and the number of horizontal scanning lines for blanking is 293, but the present invention is not limited to these numbers. , the most appropriate number can be selected depending on the type of device to which the present invention is applied. In addition, in this embodiment, as a television receiver,
I used an NTSC system, but of course you can also use a regular black and white TV receiver, and even
Television receivers such as PAL and SECAM systems can also be used.

As explained above, according to the present invention, the line buffer used in the digital scan converter of conventional ultrasonic diagnostic equipment can be eliminated, and the complicated control circuit for controlling it can be eliminated. This allows the device to be made smaller and less expensive.

[Brief explanation of drawings]

FIG. 1 is a block configuration diagram showing the general configuration of a conventional ultrasonic diagnostic apparatus. FIG. 2 is a diagram showing the signal format of a video signal for explaining the method of the present invention. Third
The figure is a block diagram of a digital scan converter implementing the method of the present invention. 31...A/D converter, 32A, 32B...Frame memory, 38...D/A converter for video, 39...Read address/timing generator, 40...Write address/timing generator, 46 ...TV synchronization generator, 47...timing generator.

Claims (1)

[Claims] 1. A wave transmitting/receiving circuit that irradiates an ultrasonic pulse toward an object to be diagnosed, receives reflected waves reflected by the object to be diagnosed, and outputs an analog reflected wave signal, and a frame.・Includes a memory, converts the reflected wave signal from the above wave transmitting/receiving circuit into a digital quantity and writes it into this frame memory, and converts the data read from this frame memory into an analog quantity in order to display the image on a television receiver. The conversion circuit is configured to display the diagnostic image on the screen of the television receiver by converting the diagnostic image based on the reflected wave signal obtained by the wave transmitting/receiving circuit into one vertical synchronizing signal section. means for displaying using a part of the series of horizontal scanning lines and blanking the remaining series of horizontal scanning lines; During the time to display the image, data is read from the frame memory, and during the blanking time using the remaining horizontal scanning lines, the transmitter/receiver circuit transmits and receives ultrasonic pulses, and the transmitter/receiver transmits and receives the ultrasonic pulses. An ultrasonic diagnostic apparatus comprising: means for writing a reflected wave signal obtained from the circuit into the frame memory.