JPH0443213Y2 - - Google Patents

Description

[Detailed description of the invention] (a) Industrial application field The present invention relates to an ultrasonic diagnostic apparatus, and in particular, a contour enhancement circuit ( enhancement circuit)
Regarding.

(b) Prior art and its problems Generally, in an ultrasonic diagnostic apparatus, the outline of a diagnostic image is emphasized by an outline enhancement circuit to make the image easier to see. This contour enhancement is performed using the original echo signal E1 shown in FIG. 3A, and the original echo signal E1 shown in FIG.
Based on the first and second delayed echo signals E2 and E3 respectively shown in C, predetermined coefficient values k1 and k
By multiplying by 2, the contour emphasis signal E4 (=E2-k1・E1-k2・
E3).

However, in such a conventional contour enhancement circuit, although the high frequency components of the echo signal are attenuated as it passes through the human body, the delay time t
1, t2 and the coefficient values k1, k2 are set constant in advance, so that, for example, as shown in FIG.
In the case of the echo signal shown in Figure 4B, if the degree of contour enhancement in shallow areas is set to be optimal, the contours in deep areas will not be sufficiently emphasized as shown in Figure 4B. On the other hand, if the degree of contour enhancement in deep areas is set to be optimal, as shown in Figure 4C, the contours in shallow areas will be overemphasized, resulting in an unnatural image. I become confused. In addition, in FIG. 4, the left side corresponds to the shallow part, and the right side corresponds to the deep part.

The present invention has been developed in view of the above-mentioned points, and an object of the present invention is to enable natural contour enhancement from shallow to deep areas.

(c) Means for solving the problem In order to achieve the above-mentioned purpose, the present invention uses ultrasonic waves that form an edge-enhancing signal based on an echo signal and a delayed echo signal obtained by delaying the echo signal. In the contour enhancement circuit of the diagnostic device, a first variable delay circuit that delays and outputs the echo signal;
a second variable delay circuit that delays and outputs the delayed echo signal; a first variable multiplication circuit that multiplies the echo signal by a coefficient value; and a second variable multiplication circuit that multiplies the delayed echo signal from the second variable delay circuit by a coefficient value. It includes a variable multiplier circuit, and a control circuit that varies the delay times of the first and second variable delay circuits and the coefficient values of the first and second variable multiplier circuits in accordance with the passage of time after transmitting the ultrasonic wave. .

(D) Effect According to the above configuration, the delay time and the coefficient value can be changed according to the passage of time after the ultrasonic wave is transmitted, and thereby the degree of contour enhancement can be adjusted from the shallow part to the deep part. will be adjusted optimally.

(e) Embodiments Examples of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a block diagram of one embodiment of the present invention. The contour emphasizing circuit 1 of this embodiment is as follows:
The ultrasonic diagnostic apparatus is provided with an echo signal E1 from a subject to be applied to an input terminal 2, and a timing signal P for transmitting ultrasonic waves to an input terminal 3.

This contour enhancement circuit 1 includes a first variable delay circuit 4 that delays the echo signal E1, a second variable delay circuit 5 that delays the first delayed echo signal E2 from the first variable delay circuit 4, and a second variable delay circuit 5 that delays the first delayed echo signal E2 from the first variable delay circuit 4. A first variable multiplier circuit 6 that multiplies the second delayed echo signal E3 from the second variable delay circuit 5 by a coefficient value, a second multiplier circuit 7 that multiplies the second delayed echo signal E3 from the second variable delay circuit 5 by a coefficient value, and a first A third variable multiplication circuit 8 that multiplies the delayed echo signal E2 by a coefficient value, and an arithmetic circuit 10 that calculates the outputs of the first, second, and third variable multiplication circuits 6, 7, and 8.
and a control circuit 9 for controlling these.

The first and second variable delay circuits 4 and 5 are connected to a control circuit 9
The first and second delay time control signals Sa1 and Sa2 from
The first, second, and third variable multiplier circuits 6, 7, and 8 are configured to vary the delay time based on the first, second, and third coefficient values from the control circuit 9. The coefficient values are configured to vary in correspondence to control signals Sb1, Sb2, and Sb3, respectively. For example, when the first and second variable delay circuits 4 and 5 are configured with coils and capacitors, they can be controlled with variable capacitance diodes, etc.
The first to third variable multiplication circuits 6 to 8 can be configured with field effect transistors or the like.

The arithmetic circuit 10 subtracts the outputs of the first and second variable multipliers 6 and 7 from the output of the third variable multiplier 8, and outputs the result as an edge emphasis signal E4.

The control circuit 9 controls each variable so that both the delay time and the coefficient value increase as time elapses from the transmission of the ultrasonic wave, that is, as it progresses from the shallow part to the deep part, based on the transmission timing signal P. Controls delay circuits 4 and 5 and first to third variable multiplication circuits 6 to 8.

That is, the contour emphasizing circuit 1 of the present invention is configured so that the deeper the echo signal, the greater the attenuation of high-frequency components, and the deeper the echo signal, the higher the degree of contour enhancement.

In this way, the delay times of the first and second variable delay circuits 4 and 5 and the coefficient values of the first to third variable multiplier circuits 6 to 8 are made to increase as time passes after ultrasonic wave transmission. Therefore, for example, if the original echo signal is as shown in Figure 2A, the contour will become more emphasized as it goes deeper, as the high frequency components attenuate. As shown in the contour enhancement signal E4 in FIG. B, optimal contour enhancement is performed from deep to deep, resulting in a natural image.

(F) Effects As described above, according to the present invention, the echo signal and
In an edge enhancement circuit of an ultrasound diagnostic apparatus that forms an edge enhancement signal based on a delayed echo signal obtained by delaying the echo signal, the edge enhancement circuit includes a first variable delay circuit that delays and outputs the echo signal, and a first variable delay circuit that delays and outputs the echo signal; a second variable delay circuit that delays and outputs the
a first variable multiplication circuit that multiplies the echo signal by a coefficient value; a second variable multiplication circuit that multiplies the delayed echo signal from the second variable delay circuit by a coefficient value; A control circuit that varies the delay time of the first and second variable delay circuits and the coefficient values of the first and second variable multiplier circuits is provided, and the control circuit is provided to accommodate the high frequency component of the echo signal that attenuates as it progresses from the shallow part to the deep part. Since the degree of contour enhancement is further increased, optimal contour enhancement is achieved from shallow to deep areas.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of an embodiment of the present invention;
1 is a signal waveform diagram of the embodiment shown in FIG. 1, FIG. 3 is a signal waveform diagram for explaining the principle of edge enhancement, and FIG. 4 is a signal waveform diagram of a conventional example. 1... Contour emphasis circuit (enhancement circuit), 4,
5...First and second variable delay circuits, 6-8...First
~Third variable multiplier circuit, 9...control circuit.

Claims (1)

[Claims for Utility Model Registration] In a contour enhancement circuit of an ultrasound diagnostic device that forms a contour enhancement signal based on an echo signal and a delayed echo signal obtained by delaying the echo signal, the echo signal is delayed and outputted. a first variable delay circuit that delays and outputs the delayed echo signal; a first variable multiplication circuit that multiplies the echo signal by a coefficient value; and a delayed echo from the second variable delay circuit. a second variable multiplication circuit that multiplies a signal by a coefficient value; and a variable delay time of the first and second variable delay circuits and coefficient values of the first and second variable multiplication circuits according to the passage of time after ultrasonic wave transmission. 1. A contour enhancement circuit for an ultrasonic diagnostic apparatus, comprising: a control circuit for controlling the contour of an ultrasonic diagnostic apparatus.