JPH0312141A - Ultrasonic diagnostic device - Google Patents

Abstract

PURPOSE:To precisely control transmission delay time without requiring a counter circuit, for which expansive super high-speed operating element are sued, by providing a delay circuit to output plural clock signals, for which a reference clock signal is delayed to plural steps, and a selecting circuit. CONSTITUTION:In a delay circuit 2, an n-pieces of output terminals are wholly connected to an n-pieces of selecting circuits 3a-3n and the output terminals of the respective selecting circuits 3a-3n are respectively connected to an n-pieces of counter circuits 4a-4n. Then, the terminals of these counter circuits are respectively connected to transmission circuits 5a-5n. Clock signals Ca-Cn, which are delayed to n-steps based on arbitrary delay time Ta-Tn, are generated by the delay circuit 2. These clock signals Ca-Cn are inputted to the respective selecting circuits 3a-3n, respectively alternatively selected and afterwards, counted by the respective counter circuits 4a-4n. Accordingly, the transmission delay time through the transmission circuits 5a-5n can be precisely controlled only for the number of the delayed steps in the delay circuit 2 without depending on a reference clock signal period T.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an ultrasonic diagnostic device, and more specifically, an ultrasonic diagnostic device that sets a focal position during transmission of an ultrasonic beam using an electronic circuit, and particularly The present invention relates to an ultrasonic diagnostic device that uses a counter circuit to control transmission delay time.

(Prior art) Ultrasonic diagnostic equipment, which transmits ultrasound beams toward a living body and displays reflected waves from inside the living body, is widely used in clinical diagnosis because of its high safety and ease of use. It is being In order to obtain more accurate diagnosis contents, such an ultrasonic diagnostic apparatus is required to be able to obtain a clear and focused image at any part of the diagnostic region.

Here, as shown in FIG. 4, the conventional ultrasonic diagnostic apparatus includes a clock signal generation circuit 11 and a counter circuit that counts clock signals and sends out a transmission timing pulse when the count value reaches a certain value. 14, a transmission circuit 15 that receives the transmission timing pulse and drives an ultrasonic transducer (not shown), and a trigger signal generation circuit 16 that sends a trigger signal to the clock signal generation circuit 11 and the counter circuit 14. There is. Although not shown, a plurality of counter circuits 14 and a plurality of transmission circuits 15 are provided corresponding to the number of ultrasonic transducers.

In the ultrasonic diagnostic apparatus having the above configuration, the counter circuit 1
The clock signal generation circuit 11 uses an ultra-high-speed operating element in 4.
By shortening the clock signal period, the transmission delay time required for setting the focal position is finely controlled.

(Problems to be Solved by the Invention) In the conventional ultrasonic diagnostic apparatus described above, for example, 10 (ns)
) When controlling the transmission delay time with a time resolution of It is necessary to configure using

However, this makes circuit design difficult, and there are also problems such as increased power consumption of the circuit and increased parts cost.

The present invention has been made to solve the above problems,
The objective is to provide an ultrasonic diagnostic apparatus that can finely control transmission delay time without requiring a counter circuit using expensive ultra-high-speed operating elements.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides a reference clock signal S from a clock signal generation circuit 1, as shown in FIG.
A plurality of clock signals Ca are obtained by delaying the reference clock signal S in a plurality of stages without inputting it directly to the counter circuit 4.
, Cb, ..., Delay circuit 2 that outputs Cn
and the plurality of clock signals Ca.

A selection circuit 3 which selects one of Cb, . . . , Cn and outputs it to a count circuit 4 is added.

In FIG. 1, reference numeral 5 indicates a transmitting circuit, and reference numeral 6 indicates a trigger signal generation circuit that outputs a trigger signal for starting/stopping/resetting the clock signal generation circuit 1 and the counter circuit 4, respectively.

In short, the ultrasonic diagnostic apparatus according to the present invention is an ultrasonic diagnostic apparatus that controls the transmission delay time of an ultrasonic beam based on a count value of a clock signal by a counter circuit. a delay circuit that outputs a clock signal; and a selection circuit that selects one of the plurality of clock signals output from the delay circuit and outputs it to the counting circuit, the transmission delay time being equal to the reference clock. Control is performed with a time resolution shorter than the signal period.

(Function) According to the present invention, first, a reference clock signal S having a period T as shown in FIG. 2 is output from the clock signal generation circuit 1 to the delay circuit 2. In the delay circuit 2, the delay times from n output terminals are Ta, Tb, ......, T
A plurality of delayed clock signals Ca, Cb, .
..., Cn are output, and these clock signals C
a, Cb, . . . , Cn are input to the selection circuit 3.

The selection circuit 3 uses the clock signals Ca, Cb, . . .
- Select one from Cn and output it to the counter circuit 4. For example, when the clock signal cb is selected in the selection circuit 3 and the count value of the counter circuit 4 is set to M, the transmission delay time is TXM+Tb+K (K is the delay time specific to the circuit), where the delay time Tb can be selected independently of the reference clock signal period T, so
According to the present invention, the transmission delay time of an ultrasound beam can be controlled for a time shorter than the clock signal period T with resolution.

(Example) An embodiment of the present invention will be described below with reference to FIG.

FIG. 3 shows the configuration of an embodiment of the present invention, where 1 is a clock signal generation circuit and 2 is a clock signal generation circuit that delays the reference clock signal S in multiple stages (n stages) to generate n clock signals as in FIG. 1. A delay circuit 6 converts the clock signal Ca=Cn, and a trigger signal generating circuit 6 outputs a trigger signal for starting/stopping/resetting the clock signal generating circuit 1 and counter circuits 4a to 4n, which will be described later.

The n output terminals of the delay circuit 2 are connected to the n selection circuits 38 to 3.
The output terminals of each selection circuit 38 to 3n are connected to n counter circuits 4a to 4n, respectively, and the output terminals of each counter circuit 4a to 4n are connected to transmission circuits 58 to 5n, respectively. has been done. and,
Although not shown, n ultrasonic transducers are connected to each of the transmitting circuits 58 to 5n.

According to this embodiment, by using a single relatively expensive delay circuit 2 and connecting its output terminal in common to n selection circuits 38 to 3n, the cost of the entire circuit including the delay circuit can be reduced. It is possible to reduce the number of parts and the number of parts.

Regarding the operation of this circuit, as is already clear, the delay circuit 2 generates the clock signal Ca=Cn delayed by n stages based on an arbitrary delay time Ta''Tn, and these clock signals Ca=Cn are Selection circuit 38-3
n and are selectively selected, respectively, and used for counting in each of the counter circuits 4a to 4n, so that the transmission delay time via the transmission circuits 58 to 5n depends on the reference clock signal period T. It is possible to perform fine control by the number of delay stages in the delay circuit 2 without having to do so.

Further, due to the above principle, it is not necessary to use ultra-high speed operating elements as the counter circuits 4a to 4n.

The present invention is applicable to various ultrasonic diagnostic apparatuses regardless of the type of probe, such as linear type, convex type, annular type, etc., as long as the focal position is electronically controlled.

(Effects of the Invention) As described above, according to the present invention, the clock signal is delayed and selected in multiple stages without depending on the reference clock signal period, and then counted.
Counter circuits that used ultra-high-speed operating elements such as
It can be configured using general operating elements such as MO8, and it is possible to simplify circuit design, reduce size through high integration, and reduce power consumption and component costs.

Therefore, there are effects such as the ability to greatly contribute to the realization of an inexpensive ultrasonic diagnostic apparatus with accurate diagnostic content.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of the present invention, FIG. 2 is a timing chart for explaining the operation, FIG. 3 is a block diagram showing an embodiment of the present invention, and FIG. 4 is a block diagram showing the conventional technology. FIG. 1... Clock signal generation circuit 3.3a-3n... Selection circuit 4.4a-4n... Counter circuit 5.5a-5n... Transmission circuit 6... Trigger signal generation circuit 2... Delay Circuit s1 diagram

Claims (1)

[Scope of claims] An ultrasound diagnostic apparatus that controls the transmission delay time of an ultrasound beam based on a count value of a clock signal by a counter circuit, which outputs a plurality of clock signals obtained by delaying a reference clock signal in multiple stages. and a selection circuit that selects one of the plurality of clock signals outputted from the delay circuit and outputs it to the counting circuit, the transmission delay time being longer than the period of the reference clock signal. An ultrasonic diagnostic device characterized by control with short temporal resolution.