JPH11299777A - Ultrasonic diagnostic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the resolution in the lateral direction at a noticed portion by equipping a diagnostic device with a function to change the number of beams of ultrasonic beams at a halfway position in the scanning range to make one frame of image and reconstituting image data by RΘ interpolation corresponding to changes of the number of beams. SOLUTION: Various transmitted data are read out from RAM and ultrasonic beams transmitted from an ultrasonic vibrator 1 are controlled by a transmission control circuit 2. Echo signals received by the ultrasonic vibrator 1 are beam- formed by a beam former 3. The beam-formed data are processed by a vector processor 4 and then transmitted to a scan converter 5. Image data are constituted from vector data stored in a frame buffer 7 at the scan convertor 5 and the vector data are RΘ interpolated by an RΘinterpolation circuit 8 and converted into luster image data and the image is displayed on a monitor 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to an ultrasonic diagnostic apparatus.

[0002]

2. Description of the Related Art Conventionally, in an ultrasonic diagnostic apparatus,
An image is produced based on an echo signal obtained by transmitting an ultrasonic beam.In a conventional ultrasonic diagnostic apparatus, although not shown, a predetermined visual field width is set. It is common to scan the entire scan area with the same number of ultrasound transducers, multiples of the ultrasound transducer, or an integral number of beams, such as a quadruple. .

[0003]

The number of ultrasonic beams and the frame rate are in a reciprocal relationship, and when the number of beams is increased to improve the resolution in the lateral direction, the frame rate decreases. Was supposed to. That is, for example, when the number of ultrasonic beams is doubled, the frame rate is reduced to half, and it is very difficult to suppress the reduction of the frame rate while improving the resolution in the lateral direction. Has become. Therefore, even if it is necessary to improve the resolution in the lateral direction at a specific part of the scan area,
In practice, it is not possible to obtain sufficient resolution as needed to avoid a significant reduction in frame rate.

The present invention has been made in view of such circumstances, and has a configuration capable of minimizing the reduction of the frame rate while improving the resolution in the lateral direction at the target portion of the scan area. The purpose of the present invention is to provide an improved ultrasonic diagnostic apparatus.

[0005]

In order to achieve such an object, an ultrasonic diagnostic apparatus according to the present invention changes the number of ultrasonic beams at a position halfway in a scan area for producing an image of one frame. And a function of reconstructing image data by RΘ interpolation corresponding to a change in the number of beams. Note that the middle position of the scan area where the number of beams is changed is specified in advance.

According to the above arrangement, the number of ultrasonic beams at the target portion of the scan area, that is, at the target portion whose lateral resolution is to be improved, is different from the number of beams at other portions. Specifically, if necessary, the number of ultrasonic beams in a designated region of interest is locally changed so that the number of beams is larger than in other regions, and the number of beams is different from each other. Even if the region of interest and other regions are within the same scan area, RΘ interpolation is performed to reconstruct image data so that a normal raster image is created.

Therefore, the resolution in the lateral direction at the target portion of the scan area for producing an image of one frame is improved by the increased number of beams as compared with the other portions. When the above configuration is adopted, the frame rate is reduced in accordance with the improvement in the resolution in the lateral direction. Does not occur, it is possible to suppress the reduction of the frame rate as much as possible while improving the resolution in the lateral direction at the site of interest in the scan area.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a block diagram showing a simplified configuration of a main part of an ultrasonic diagnostic apparatus, FIG. 2 is an explanatory diagram of items relating to a scan area, and FIG. 3 is an explanation of items relating to RΘ interpolation. FIG. In the present embodiment, it is assumed that the ultrasonic diagnostic apparatus is a sector scan type, but the present invention is not limited to the sector scan type, and may be a convex scan type or a linear scan type. Of course.

The ultrasonic diagnostic apparatus according to the present embodiment
As shown in FIG. 1, an ultrasonic transducer 1 for transmitting an ultrasonic beam and receiving an echo signal, a transmission control circuit 2 for controlling the transmission of the ultrasonic beam, A beamformer 3 for forming, a vector processor 4 for executing processes such as reception dynamic filtering and detection, a scan converter 5 for forming image data from vector data, and a monitor 6 such as a CRT for displaying a produced image. It has.

The scan converter 5 is provided with a frame buffer 7 for storing one frame of vector data.
, An RΘ interpolation circuit 8 for converting vector data into image data, and an image memory 9 for storing image data. In addition, the ultrasonic diagnostic apparatus at this time,
Transmission control circuit 2 and beamformer 3, RΘ interpolation circuit 8
And a control panel 11 used to instruct necessary operations.

Next, the operation and operation of the ultrasonic diagnostic apparatus according to the present embodiment will be described with reference to FIGS.

In the control panel 11, in the preset stage, a portion X of interest in the scan area S where the resolution in the lateral direction (indicated by an arrow A in FIG. 2) needs to be improved, that is, a scan for producing an image of one frame. The target portion X whose resolution is to be improved by increasing the number of the ultrasonic beams L at a position in the middle of the region S, for example, by doubling the number of beams, is graphically displayed, and the field width of the target portion X is displayed. And setting by designating the start position Xp. Then, parameters such as the field width of the entire scan area S, the field width of the attention site X, and the start position Xp are transmitted from the control panel 11 to the control circuit 10.

In the control circuit 10, based on the transmitted parameters, the target portion X of the scan area S, that is, the number of ultrasonic beams L is set to 2 of the number of transducers of the ultrasonic transducer 1. A site X to be increased by a factor of two, a site Y having the same number of beams as the ultrasonic transducer 1,
Z are determined, and these sites X, Y, Z
Is determined, the number of ultrasonic beams L in each part X, Y, and Z and the transmission direction are determined, and each of the transducers included in the ultrasonic transducer 1 at the time of transmission is determined. After calculating delay data for each and control data at the time of receiving, the transmission data is transmitted to the RAMs of the transmission control circuit 2 and the beamformer 3, respectively.

The transmission control circuit 2 reads out various data transmitted from the RAM and controls the ultrasonic beam L transmitted from the ultrasonic transducer 1. In 3, beam forming is performed on the echo signal received by the ultrasonic transducer 1. The beam-formed data is to be transmitted to the vector processor 4 for processing, and the processed vector data is transmitted from the vector processor 4 to the scan converter 5.

In the scan converter 5, image data is composed of the vector data stored in the frame buffer 7, and the RΘ interpolation circuit 8 converts the vector data into raster image data after performing RΘ interpolation. Be executed. Therefore, in the RΘ interpolation of each of the parts Y and Z in the scan area S, as shown in FIG. 3, four echo signal data a, b, c, and d surrounding the target pixel P to be interpolated, The address of each of the echo signal data a, b, c, and d located on a pair of adjacent ultrasonic beams L0 and L1 and the weighting data in the R and Θ directions are used, and the The address data and weighting data of P are calculated.

However, in this case, R
In the interpolation, since the number of the ultrasonic beams L is twice the number of the portions Y and Z and the ultrasonic beam L2 exists between the ultrasonic beams L0 and L1, the target pixel P to be interpolated is used. Echo signal data a, b,
c, d, e, and f are available, and the address data and weighting data of the pixel P are calculated using these echo signal data a, b, c, d, e, and f. Is performed. That is, in the target region X of the scan region, the RΘ interpolation is performed using more echo signal data than the regions Y and Z, so that the accuracy of the calculated address data and the weighted data is reduced to the positions Y and Z. More than it is.

Further, the address data and the weighting data for each pixel P are transmitted to the RAM of the RΘ interpolation circuit 8, and the image data of each pixel P stored in the image memory 9 is stored in a frame buffer. 7 by interpolating the vector data read from the address data 7 using the address data calculated by the RΘ interpolation circuit 8. Then, the image composed of the image data thus configured is displayed on the monitor 6.

[0018]

As described above, according to the ultrasonic diagnostic apparatus of the present invention, when it is necessary to improve the resolution in the lateral direction at a specific target part of the scan area, the ultrasonic diagnostic apparatus according to the present invention has the following advantages. The resolution in the lateral direction can be improved by an increase in the number of beams as compared with other portions. Therefore, even if the frame rate may decrease due to the improvement in the resolution in the lateral direction, there is no practical effect as long as the region of interest in the scan area is not so large, and the resolution in the lateral direction at the region of interest does not occur. The effect that the reduction of the frame rate can be suppressed as much as possible while improving the image quality can be obtained.

[Brief description of the drawings]

FIG. 1 is a simplified block diagram showing a configuration of a main part of an ultrasonic diagnostic apparatus.

FIG. 2 is an explanatory diagram of items related to a scan area.

FIG. 3 is an explanatory diagram of matters related to RΘ interpolation.

[Explanation of symbols]

 L Ultrasonic beam S Scan area X Attention site

Claims (1)

[Claims] 1. A function of changing the number of ultrasonic beams at an intermediate position in a scan region for producing an image of one frame, and reconstructing image data by RΘ interpolation corresponding to the change in the number of beams. An ultrasonic diagnostic apparatus, comprising: