JPS58152552A - Display system of linear scanning type ultrasonic tomography apparatus - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in the display method of a linear scanning ultrasonic tomography apparatus.

Conventional linear scanning ultrasonic tomography devices usually display depth information up to 18CIn, as shown by the solid line in Figure 1, but as shown by the dotted line in Figure 1, depth information is displayed up to 23Cr.
In order to make it possible to observe up to
, the period t2 must be 23 Cm. However, these cycles 1. Since and t are fixed, the time T! to obtain one tomographic image is fixed. takes longer than the time T required to actually display a tomographic image. In other words, it takes a length of T, -T to obtain one tomographic image.

Therefore, in the 23α display shown by the dotted line in FIG. 1, deep information can be obtained to a great depth, but it takes an unnecessary time of Tz T1 to obtain one tomographic image from 00 to 18C. Furthermore, this has the disadvantage that the number of frames for displaying tomographic images is reduced compared to the 18 m display shown in FIG. 1, and flickering increases.

The present invention has been made to eliminate the above-mentioned drawbacks, and its characteristics are that when deep information is not observed, a tomographic image is displayed with a short ultrasound pulse repetition period, and deep information is When a tomographic image is displayed at a pulse repetition period and deep information is to be observed, a means for displaying the tomographic image at a long ultrasonic pulse repetition period is provided.

The principle and embodiments of the present invention will be explained below.

(1) Principle of the present invention FIG. 3 is a diagram for explaining the present invention in detail.
A) is an ultrasonic pulse repetition signal, (B) is a Y scan synchronization signal, and (C) is a Y' scan synchronization signal.

Depth 1), cm (
For example, when observing an object part up to 18CrIl), if the sound velocity is Ccm/sec, the time required to display one Y scan line, that is, the period 1 of Y scan synchronization signal B + (ultrasonic pulse The period of the repetitive signal A) is just fine. Assuming that n Y scanning lines are required to obtain one tomographic image (one frame), the time required to obtain one tomographic image is nt seconds, and a tomographic image of depth DlcnL is required. N to display the image.

If a frame is required, the time it takes is N.

Xnt, seconds.

Here, DtCI is made deeper than the depth D1CrrL.
rL (for example, 23CrfL), the ultrasonic pulse repetition signals A' and Y' at this time, as shown in FIG.
The period t of the scan synchronization signal C is longer than the period t1 of the Y scan synchronization signal A by Δt, and the time required to create one tomographic image is also long, so the present invention provides If information up to D2α is not observed,
The tomographic image is displayed at the period t of the Y-scan synchronization signal, and the depth D
2 CIrL'! When observing information at , the tomographic image is displayed at the period t2 of the Y' scan synchronization signal.

For example, as shown in FIG.
) Crn, even if the display start point of the tomographic image is moved by ΔDcm in the display field, the time required to create one tomographic image is n(.

Therefore, flickering does not occur when information is displayed at depths of 0 to D and cml. Therefore, as shown in FIG. 4, when the tomographic image passes the point P where the display field of view has moved by the amount ΔD, the period of the ultrasonic pulse repetition signal A' and Y' scan synchronization signal C is switched to t2. , the time required to create one tomographic image n(.

A tomographic image at a depth D t (?m'4) can be displayed.

(2) Embodiment of the present invention FIG. 5 is a diagram showing the structure of an embodiment made in accordance with the principle of the present invention. In the figure, 1 is an ultrasonic probe, 2 is an ultrasonic transmitter/receiver, and 6 is a digital scan gomber M.
, 4i1 A display device such as a television, l/monitor, etc. 5 is an ultrasonic pulse repetition period t.

6 is a delay circuit, and 7 is a Y' scanning synchronizing signal generator.

Next, the operation of this embodiment will be explained.

Now, when the display field of view position setter 5 is set to the ultrasonic pulse repetition period t1, the delay circuit 6 operates and converts the address of the Y' scan synchronization signal generator 7 to an address delayed by Δt as shown in FIG. Then, the Y scan synchronization signal (B
) and input it to the ultrasonic transmitter/receiver 2 and the digital scan controller 3. As a result, the repetition period t
, are emitted and displayed on the information nine-ball display device 4 at depths 0-p and Crn. If the display field of view position setter 5 is reset, the delay circuit 6 does not operate, so a Y-scan synchronization signal (0) with a period of t is generated, and the ultrasonic transmitter/receiver 2 and the digital scan controller 3 Input the repetition period t.

An ultrasonic pulse is emitted, and information on depths from 0 to DxCm is displayed on display wave #4.

In addition, a display field movement detector is provided in place of the display field position setting device 5, and when the point P is exceeded, the display field position is automatically adjusted to the period t2 of the ultrasonic pulse repetition signal A' and Y' scanning synchronization signal (C). It is also possible to switch between the two.

Of course, various changes may be made without changing the gist of the above.

As explained above, according to the present invention, when deep information is not observed, a tomographic image is displayed with a short ultrasound pulse repetition period, and when deep information is observed, a tomographic image is displayed with a long ultrasound pulse repetition period. Since the tomographic image is displayed at , when observing a relatively shallow area from zero depth to a predetermined depth, the number of frames required to display the tomographic image must be reduced to avoid flickering. It is also possible to observe deep information.

[Brief explanation of drawings]

1 and 2 are diagrams for explaining the problems of the display method of the conventional linear scanning ultrasonic tomography apparatus, and FIGS. 3 and 4 are diagrams for explaining the present invention in detail. , FIG. 5 is a diagram showing the configuration of an embodiment of the present invention. 1 Ultrasonic probe 2 Ultrasonic transmitting/receiving section 3 Digital scan converter section 4 Display device 5 Display field of view position setter 6 Delay circuit 7-, Y' scan synchronization signal generator agent Patent attorney Aki 1) Shu Kidai 1 Figure 2 Figure 5

Claims (1)

[Claims] In an IJ near-scanning ultrasonic tomography device, when deep information is not observed, tomographic images are displayed with a short ultrasound pulse repetition cycle, and when deep information is to be observed, tomographic images are displayed with a long ultrasound pulse repetition cycle. 1. A display method for a linear scanning ultrasonic tomography apparatus, characterized by comprising means for displaying.