JPH069620Y2 - Ultrasonic diagnostic equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (A) Field of Industrial Application The present invention mainly relates to a sector scanning ultrasonic diagnostic apparatus.

(B) Conventional technology and its problems In the conventional apparatus of this type, transmission and reception are performed while sector-scanning the ultrasonic beam in a sector shape, and the echo signal obtained thereby is stored in the image memory. Then, the echo signal data stored in the image memory is read as image data at the TV scanning speed in synchronization with the TV synchronizing signal, and this is displayed on the TV monitor. In this case, as shown in FIG. 3, echo signal data is written in a fan shape in the image memory in response to the ultrasonic sector scan. On the other hand, when reading the echo signal data from the image memory, T
The data is read out in the horizontal direction, for example, according to the V scanning direction.

By the way, when the echo signal data is written in the image memory for each sector scan line of ultrasonic waves, there are empty pixels in which data is not written between the sector scan lines. The number of empty pixels tends to increase toward the bottom of the fan. Therefore, when such echo signal data including many empty pixels is read out as it is and displayed on a TV monitor, a so-called moire pattern appears and the image becomes difficult to see. Therefore, conventionally, an interpolation circuit for interpolating between sector scan lines based on the echo signal data read from the image memory is provided, and the interpolation data created by this interpolation circuit is output to the TV monitor together with the echo signal data. .

As shown in FIG. 4, the interpolation at that time is performed between the echo signal data Dn and Dn _{+ 1} which are equidistant from the transmitting / receiving point o along the direction of the sector scanning line. It is originally preferable in that an interpolated image with high fidelity can be obtained, but for that reason, the circuit configuration becomes extremely complicated. Therefore, conventionally, interpolation is performed by adding and averaging the echo signal data Dn 'and Dn _{+ 1} ' before and after along the TV scanning direction.

However, although such an interpolation has a simple circuit structure, the data Dn 'and Dn _{+ 1} ' have a weak relationship with each other, so that the fidelity of the interpolated image becomes low and the brightness of the displayed image changes. Was discontinuous and the image quality was impaired.

The present invention has been made in view of the above circumstances, and has a relatively simple circuit configuration so as to complement the conventional drawbacks and can perform high-fidelity interpolation processing to obtain a good image quality. It is intended to display the sector scan image of.

(C) Means for Solving the Problems In order to achieve the above object, the present invention provides an image memory for storing digitized echo signal data obtained by sector-scanning ultrasonic waves, and this image memory. Contents of T
In an ultrasonic diagnostic apparatus for reading and displaying at a V scanning speed, data corresponding to one sector scanning line of the echo signal before being stored in the image memory is stored in a preceding stage on the echo signal input side of the image memory. At least two first, second
Line buffer memory, and an averaging circuit for averaging the previous data of the echo signal read from one of the line buffer memories and the present data stored in the other line buffer memory. A selection circuit for alternately selecting and outputting the averaged data from the averaging circuit and the echo signal data from the transducer side; and storing the data selected and output by the selection circuit as image data. An image memory and image data read out from the image memory at a TV scanning speed are input, and one of the echo signal data from the image memory is added with the averaged data. On average, between the two data,
And an interpolating circuit for adding and averaging the other echo signal data and the averaged data to interpolate between the two data along the TV scanning direction, respectively. It is characterized in that the echo signal data is output to the TV monitor.

(D) Function In the present invention, the echo signal obtained by sector scanning ultrasonic waves is first stored in one of the line buffer memories before one is stored in the image memory. Is memorized. At this time, the previous data of the echo signal corresponding to one sector scanning line which has already been stored is sequentially read from the other line buffer memories. Then, this previous data and the current data of the echo signal currently being stored in one of the line buffer memories are commonly input to the averaging circuit. The averaging circuit averages the current data and the previous data. The averaged data output from the averaging circuit and the current data are alternately selected by the selection circuit, and the selected data is stored in the image memory. Therefore, the current data and the averaged data of the echo signal are alternately stored in the image memory along the direction of the sector scanning line. Then, from the image memory, T
These data read at the V scanning speed are interpolated between the sector scanning lines along the TV scanning direction by the interpolation circuit, and these interpolation data are output to the TV monitor together with the echo signal data and the averaged data.

As described above, in the ultrasonic diagnostic apparatus of the present invention, before the echo signal data obtained by the sector scan is written in the image memory, based on these echo signal data, there is a mutual relation between the data and the fidelity. High interpolation data is created, and this interpolation data is written in the image memory together with the echo signal data. Then, the data read from the image memory at the TV scanning speed is interpolated by adding and averaging the data before and after the data along the TV scanning direction in the interpolation circuit, as in the conventional case.

(E) Embodiment FIG. 1 is a block diagram of an ultrasonic diagnostic apparatus according to an embodiment of the present invention. In the figure, reference numeral 1 indicates the whole ultrasonic diagnostic apparatus, 2 is a transducer for sector-scanning ultrasonic waves toward a subject, and 4 is a drive pulse for exciting the transducer 2 and an echo from the transducer 2. It is a transmission / reception circuit that amplifies and detects signals. Reference numeral 6 is an A / D converter for digitizing the echo signal from the transmission / reception circuit 4.

The feature of this embodiment is that first and second line buffer memories 8, 10, A for storing data corresponding to one sector scan line of the echo signal are provided in the preceding stage on the echo signal input side of the image memory 22 described later. / D converter 6 and first and second line buffer memories 8 and 10 for switching the connection between the first switching circuit 14, the first and second line buffer memories 8 and 10 to select the echo signal data output read The second switching circuit 16, the first line buffer memory 8 or the second
From the averaging circuit 18 and the averaging circuit 18 for averaging the previous data of the echo signal read from the line buffer memory 10 and the current data of the echo signal stored in the first or second line buffer memory 8 or 10. That is, a selection circuit 20 for selecting and outputting the output averaged data and the current data is provided. When the first switching circuit 14 is connected to the first line buffer memory 8, the second switching circuit 16 is connected to the second line buffer memory 10, and vice versa.
When connected to the line buffer memory 10, the second
The switching circuit 16 is connected to the first line buffer memory 8.

Reference numeral 22 is an image memory for storing echo signal data as image data, 24 is an interpolation circuit for creating interpolation data for interpolating between sector scan lines based on the echo signal data read from the image memory 22 at the TV scanning speed, 26 Is D /
A converter, 28 is a TV synchronizing signal generating circuit, 30 is an adding circuit for superimposing the output of the D / A converter 26 on the TV synchronizing signal, 32 is a TV monitor, 34 is the first and second switching circuits 14 and 16. The control circuit controls the operation of the selection circuit 20 and the operation of writing and reading the echo signal data to and from the image memory 22.

Next, the operation of displaying a tomographic image by sector scanning in the ultrasonic diagnostic apparatus of this embodiment will be described.

First, when the ultrasonic wave is transmitted / received while the ultrasonic beam is sector-scanned by the transducer 2, an echo signal corresponding to the received ultrasonic echo is output from the transducer 2, and the echo signal is transmitted / received by the transmitting / receiving circuit 4. Amplification and detection are performed, and this is further digitized by the A / D converter 6, and then sent to the first switching circuit 14, the averaging circuit 18 and the selection circuit 20, respectively.

The first switching circuit 14 receives the echo signal data for one ultrasonic scanning line in response to a control signal given from the control circuit 34, and outputs the first and second line buffer memories 8 and 1 each time.
Alternate 0 connections. So, for example,
When the first switching circuit 14 is connected to the first line buffer memory 8, the echo signal data for one ultrasonic scanning line is stored in the first line buffer memory 8. At this time, since the second switching circuit 16 is connected to the second line buffer memory 10, the previous data of the echo signal corresponding to one sector scan line already stored from the second line buffer memory 10 is stored. It is read out sequentially. Then, since the previous data and the current data of the echo signal being stored in the first line buffer memory 8 are commonly input to the averaging circuit 18, the averaging circuit 18 compares the current data and the previous data. Average out. That is, by the averaging circuit 18, as shown in FIG.
Averaged data Dm that interpolate between the data Dn and Dn ₊₁ equidistant from
Is obtained.

The averaging data obtained by the averaging circuit 18 and the current data digitized by the A / D converter 6 are selected by the selecting circuit 20.
Are alternately selected, and the selected data is stored in the image memory 22.
Memorized in. Therefore, the current data and the averaged data of the echo signal are sequentially written in the image memory 22 along the direction of the sector scanning line.

Then, these data read out from the image memory at the TV scanning speed are given to the interpolation circuit 24 in the next stage. As shown in FIG. 2, the interpolation circuit 24 is based on the echo signal data Dn ′, Dn _{+ 1} ′ obtained corresponding to the sector scanning line and the averaged data Dm obtained by the averaging circuit 18. , And interpolate between these data along the TV scanning direction to create interpolated data Da and Db. The interpolated data obtained by the interpolator 24 is analogized by the D / A converter 26 together with the echo signal data and the averaged data, and then superimposed on the TV sync signal by the adder 30 and output to the TV monitor 32.

Therefore, the data output to the TV monitor 32 is interpolated before and after being stored in the image memory 22, so that the amount of data is increased as a whole and a moire pattern does not appear on the screen.

In this embodiment, the first and second run-in buffer memories 8 and 10 are provided in only one stage, but they may be provided in a plurality of stages. In this case, since a plurality of averaged data for interpolating between ultrasonic scanning lines can be obtained, interpolation data with higher fidelity can be obtained.

Further, by simultaneously reading the old data and writing the new data, the first and second switching circuits 14 and 16 are
Can be omitted, and the first and second line buffer memories 8 and 10 can be combined into one line buffer memory.

(F) Effect As described above, according to the present invention, before the echo signals obtained by the sector scanning are written in the image memory, the echo signal data which are equidistant from the transmitting / receiving point along the direction of the sector scanning line can be exchanged. After performing the averaging process between them to create interpolation data with high fidelity that is related to the data, and write this interpolation data in the image memory together with the echo signal data,
Further, the interpolating circuit performs interpolation by adding and averaging the data before and after along the TV scanning direction read out from the image memory at the TV scanning speed, so that the conventional drawbacks are complemented and the circuit configuration is relatively simple. Therefore, it is possible to perform interpolation processing with high fidelity, and it is possible to display an excellent effect such that a sector scan image with good image quality can be displayed.

[Brief description of drawings]

FIG. 1 is a block diagram of an ultrasonic diagnostic apparatus according to an embodiment of the present invention, FIG. 2 is an explanatory diagram of a method for creating interpolation data in this apparatus, and FIG. 3 is an operation for writing and reading echo signal data to and from an image memory. FIG. 4 is an explanatory view of a conventional interpolation method. 1 ... Ultrasonic diagnostic device, 8, 10 ... First and second line buffer memories, 18 ... Averaging circuit, 20 ... Selection circuit, 22 ... Image memory, 24 ... Interpolation circuit.

Claims (1)

[Scope of utility model registration request] 1. An image memory for storing digitized echo signal data obtained by sector-scanning ultrasonic waves,
In an ultrasonic diagnostic apparatus for reading out and displaying the contents of the image memory at a TV scanning speed, a sector scan line of the echo signal before being stored in the image memory is provided in a stage preceding the echo signal input side of the image memory. Storing at least two first and second data corresponding to
Line buffer memory, and an averaging circuit for averaging the previous data of the echo signal read from one of these line buffer memories and the current data stored in the other line buffer memory. A selection circuit for alternately selecting and outputting the averaged data from the averaging circuit and the echo signal data from the transducer side; and storing the data selected and output by the selection circuit as image data. An image memory and image data read from the image memory at a TV scanning speed are input, and one of the echo signal data from the image memory is added with the averaged data. On average, between the two data,
And an interpolating circuit for arithmetically averaging the other echo signal data and the averaged data to interpolate between the two data along the TV scanning direction, respectively. The interpolated data by the interpolating circuit, the averaged data, and the An ultrasonic diagnostic apparatus, which outputs echo signal data to a TV monitor.