JPS58206736A - Ultrasonic diagnostic 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] [Technical Field of the Invention] The present invention relates to an ultrasonic device that transmits ultrasonic pulses toward the human body and captures and captures the ultrasonic pulses reflected from a target object. Regarding diagnostic equipment. In particular, the present invention relates to a device for controlling the power of ultrasonic pulses to be transmitted.

[Background of Brother Akira]

Increasing the power of the ultrasonic pulses sent into the human body by the ultrasonic diagnostic WFR device improves the signal-to-sound ratio of the reflected waves, but increasing the transmitted power can be harmful to the human body. Therefore, the transmission power must be set to the minimum necessary.In conventional equipment, the operation
A transmission power adjustment circuit capable of adjusting the transmission power is provided.

On the other hand, an ultrasonic transducer of #lI structure with a large number of elements arranged is used, and the timing of driving the elements is slightly different, so that the ultrasonic waves propagating throughout the body depending on the distance of the target object. A device is known in which the surface has a focus of km. In other words, if all the rows of transducer elements are arranged in a VC array and the drive timing of the end elements is earlier than the drive timing of the center element, the wave front advancing inside the body will become narrower as it goes further forward, and the entire focus will be focused. It becomes like this.

By changing the drive timing, you can change the focal length.

Such a device is configured to change the focal length automatically or by manual operation depending on the distance of the object to be observed from the body surface. The objective is to automatically adjust the focal length setting and the necessary ultrasonic power to achieve II++ m and C layers.

[Purpose of the invention]

An object of the present invention is to provide a device t'i that can set the required minimum ultrasonic power RJK according to the distance from the body surface of the target to be observed.

[Summary of the Invention] The present invention is a means for automatically controlling the power of transmitted ultrasonic waves by inputting a control signal for a focus control circuit according to the distance of a target. i- Characterized by being biased.

[Example based on examples]

Section 1 is a circuit block diagram of a device according to an embodiment of the present invention.

Trigger generation circuit IQ-1 is a device that repeatedly generates one trigger pulse. Connect this Tajiki lj variable delay circuit 2 to the human crab. The output of the focus control circuit 3 is connected to the control input C of the 6J variable delay circuit 2. This aJ variable delay circuit 2
has a shift register and multiple output terminals 01.02.0
3...On is provided, and delay times T1, T2, T5... are provided for the signals applied to the human power 11, respectively.
...Tn is given and sent. This delay time T1,
T2, T5, . . . , Tn are configured to be variable depending on the signal given to the control human power C. The signals of the output terminals 01 to On are respectively applied to the trigger inputs of the transmitting circuits 4-1 to 4-n of n161. The transmitting circuits 4-1 to 4-n are commonly supplied with power supply current necessary for their operation from the vL power supply circuit.

Each output t of each transmitting circuit 4-1 to 4-n is supplied to a large number of elements of a transducer 7 via a transmitting/receiving coupling circuit 6.

A large number of elements are arranged in the transducer 7,
Generally, the smallest signal of the delay lid is applied to the outermost element, and No. 16 with a larger delay lid is connected to the innermost element. The received signal appearing in the wiring of each element of the transducer 7 in the housing is the known transmitting/receiving coupling circuit 6? The signal rL is applied to the receiving circuit 8 via the signal rL.

Here, the features of the present invention are as follows: L, focus control circuit 3;
where the control signal generated by is guided to the power supply circuit, and 'f
The JL source circuit 5 is configured so that the magnitude of the output voltage (or output current) is automatically controlled by this control signal. In this example? , 1. Since the power supply circuit 5 is constituted by a constant voltage circuit, it is configured to switch this voltage reference according to a control signal.

In the device configured in this way, when a short focal length 1iiik command is issued from the focus control circuit 3, the variable M extension circuit 2Vf,
Among the elements of the transducer 7, the pulse signals supplied to the elements arranged in the center are controlled so as to be delayed more than the pulse signals supplied to the elements arranged in the painful area. At this time, the wave front of the ultrasonic wave emitted by the transducer 7 and penetrating into the body operates to focus with a shallow zero shear.

'Also, the long focal length k + j from the focal side (goods) circuit 3
5%, the variable delay circuit 2 is configured such that among the elements of the transducer 7, the pulse signal supplied to the elements arranged at the center is higher than the pulse signal supplied to the elements arranged at the ends. It is played with a small delay. At this time, the wave front of the ultrasonic wave emitted by the transducer 7 operates to focus at a deep position within the body.

The ultrasonic waves penetrating into the body are reflected at acoustic impedance mismatch points in the body tissue, reach the elements of the transducer 7 again, and are converted into electrical signals. This electrical signal is input from the transmitting/receiving coupling circuit 6 to the receiving circuit 8 where it is analyzed or displayed.

In this analysis or display, the control (goods) circuit 3 is used as described above.
The accuracy is good near the focal point commanded by
h image is clear. Therefore, by sequentially changing the depth of focus from shallow to deep, it is possible to visualize objects in detail from shallow to deep over time. Also, we will focus on those who particularly wish to see the theater.
With 6 constant I/L, it is possible to view the target near the focal point in a continuous manner.

In the device of the present invention, as described above, the power of the ultrasonic pulse to be transmitted changes automatically in response to the focal point setting command 3. In other words, the focal length is lengthened to observe a position deeper than the body surface. 1. The distance that the ultrasonic waves travel inside the body becomes longer and the attenuation of the waves increases, so increase the power of the ultrasonic pulses to be transmitted.3. To observe a position shallower than the surface (, j
Since the attenuation of the ultrasonic pulse is small, the power of the ultrasonic pulse to be transmitted should be small.

In the embodiment described above, the focal length setting is in four stages, and the output control signal of the focus control circuit 3 is a 2-bit binary signal. According to this system (goods) (g), the digit positions of the shift register are disconnected and connected in the delay circuit 2.
In the L-circuit 5, constant ridge pressure standards for four glazes are switched and connected.

In the above example, the output power was changed by changing the source voltage, but it is also possible to change the ultrasonic transmission power by other methods, such as by changing the power supply current or by changing the amplitude of a manual trigger. I can do it.

The control signal does not have to be a digital signal, but may be an analog No. 18 signal.

In the example of bit 2, the focus control is performed by transmitting 4g, but it is also possible to perform focus control by the receiver, and the power of the transmitted ultrasonic wave is automatically adjusted according to the focus control of the receiver. It can be configured to operate in a controlled manner.

[Explanation of effects]

As explained above, according to the present invention, it is possible to suppress the power of the transmitted ultrasonic waves to the necessary minimum depending on the distance of the target to be observed.1. Ru. The device of the present invention has the advantage that it does not unnecessarily apply harmful ultraviolet waves to the human body, and that the operation is simple and error-prone.

[Brief explanation of the drawing]

Figure tj is a circuit block diagram of a device according to an embodiment of the present invention. l... Tri force generation circuit, 2... uJ variable delay processing circuit, 3
... Focus control circuit, t-1-4-n... Transmission circuit, 5
. . . Power supply circuit, 6. -- Transmission/reception coupling circuit, 7. Transducer, 8. Receiving circuit. Patent Applicant Yokomen IT Shin Manufacturing + 5T Daikon In
Patent Attorney Nao Takashi Ide

Claims (1)

[Claims] (1) Ultrasonic diagnosis comprising means for transmitting ultrasonic pulses toward a target object, means for receiving ultrasonic pulses reflected from the target object, and means for focusing 14111 according to the distance of the target object. The apparatus 1￥C is characterized by being equipped with a means for automatically controlling the power of the ultrasonic pulse to be transmitted (111('g)) by human power and (2) for controlling the means for performing the focus control. Ultrasound diagnostic equipment