JPS61193652A - 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 (Field of Industrial Application) The present invention relates to an ultrasonic diagnostic apparatus with improved detection capability, ie, exploration depth.

(Prior art) 8 modes of living tissue to TM (Time Moti
The ultrasonic transmission level (so-called irradiation intensity) necessary and sufficient to observe the echo image of the on > mode and the irradiation intensity necessary to detect the Doppler shift of blood flow in living tissue may be extremely difficult in some cases. There is a big gap between the two.

(Problems to be Solved by the Invention) When attempting to add Doppler capability to conventional ultrasound diagnostic equipment, the transmission level is generally insufficient, especially for deep large blood vessels or obese patients. There was a problem that effective detection ability could not be achieved.

The present invention has been made in view of the above problems, and its purpose is to amplify the power of the transmitted pulse and apply it to the probe element group without changing the timing distribution of the transmitted pulse group necessary for the array. On the other hand, it is an object of the present invention to provide an ultrasonic diagnostic apparatus in which a received signal can be transmitted to a receiving circuit inside the apparatus corresponding to the same element.

(Means for Solving the Problems) The present invention, which solves the above problems, is an ultrasonic diagnostic apparatus using an array transducer, which includes a limiter,
The array is equipped with a forward high level switch means for amplifying the power of only the transmitting pulses applied from the transmitting/receiving circuit side of the apparatus main body via the limiter, and an input signal amplifier for appropriately increasing the width of the received signal. - The high level switch means and the input signal amplifier are connected in antiparallel to each element of the transducer, and transmitting pulses and receiving signals are sent and received to the transmitting/receiving circuit side via the limiter. It is characterized by the following structure.

(Example) Examples of the present invention will be described in detail below using the drawings. FIG. 1 is a block diagram of main parts showing an embodiment of the present invention, and shows only the structure of a circuit related to one probe. Therefore, in reality, circuits having the same configuration are connected one-to-one to each element of the array. In the figure, LM is a limiter, SW is a high level switch means, and TD is an array switch.
The transducer element A M P is the input signal amplifier.

The limiter LM limits the peak value of the applied signal, and is made by, for example, connecting a Zener diode ZD with a Zener voltage of about 9 to 12 V and a normal diode D4 in anti-series, and connecting a resistor R6 in parallel to the circuit. , has an open surface that suppresses the peak value to about 10 to 16V.

The high level switch means SW amplifies the transmitted wave pulse only when it is given from the transmitter/receiver circuit of the device and applies it to the element TD. It is composed of D2, etc. The input signal amplifier AMP is designed to amplify only the signal from the element, and is composed of antiparallel connected diodes D5 to D6, a transistor 02, etc., and its output is applied to the limiter LM.

The operation in such a configuration will be described in detail below. When a pulse of 100 Vpp or more is applied from the transmitter/receiver circuit as shown in the figure, the limiter LM is applied via the capacitor C2.
added to. In the limiter LM this pulse is the second
As shown in the figure (a), it is clamped at about 10 to 16V. This signal is applied to the gate of FETQt. FET QI
A high voltage of -400 V is applied to the drain of the resistor R1 through the resistor R1, and the voltage changes as shown in FIG. 2(b). Such a drain voltage signal is connected to the capacitor C! is added to point A of the diode circuit via the diode circuit. Point A is normally approximately OV, and the connection point B with element TD changes as shown in FIG. 2(c) according to changes in the drain voltage. That is, element TD is driven with a negative pulse of 0 to -350V.

Thereby, the element TD is driven by a high-level signal and can generate ultrasonic waves with sufficient irradiation intensity.

In this case, the element drive pulse is also applied to the input signal amplifier AMP via the resistor R3, but falls to the common line through the circuit of diodes Ds and Ds, so as not to destroy the transistor Q2.

Next, the received signal from element TD is guided to the input signal amplifier AMP via resistor R3, and transistor Q2
is amplified by and guided to limiter LM. The received signal that has passed through the transistor Q2 is a weak signal of several volts or less, and is input to the transmission/reception circuit on the device main body side via the capacitor C2 without activating the FET QI.

The feature of this circuit is that when a large-amplitude, positive-rising transmission/reception pulse is sent from the main body side, it is clamped and applied to the gate of FETQr, and the power is amplified once before being applied to element TD. Next, the echo signal is amplified by the input signal amplifier AMP in the opposite direction, and then passed to the main body at the limiter LM. After the transmission pulse ends, the limiter LM has no longer clamped, so the output of the transistor Q2 is transmitted to the main body without distortion or attenuation. Further, with this configuration, there is a secondary effect that a transistor Q2 having a low breakdown voltage can be used since the transmission pulse output from the main body is not directly applied to the transistor Q2.

(Effects of the Invention) As described above, according to the present invention, it is possible to amplify the power of the transmitted pulse and improve the irradiation intensity with a simple configuration. The mode echo image observation device can also be applied to a Doppler device without changing the transmitting/receiving circuit.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram of main parts showing an embodiment of an ultrasonic diagnostic apparatus according to the present invention, and FIG. 2 is a waveform diagram of each part. LM...Limiter SW...High level switch means TD...Element AMP...Human signal amplifier Patent applicant Yokogawa Medical Systems Co., Ltd. M2 diagram

Claims (1)

[Claims] An ultrasonic diagnostic device using an array transducer, which includes a limiter, a forward high level switch means for amplifying the power of only the transmitting pulses given from the transmitting/receiving circuit side of the device main body via the limiter, and a receiving signal. The high level switch means and the input signal amplifier are connected in antiparallel to each element of the array transducer, and the transmitting pulse and the receiving signal are connected to each element of the array transducer. An ultrasonic diagnostic apparatus characterized in that the ultrasonic diagnostic apparatus is configured to transmit and receive the signal to and from the transmitting/receiving circuit via the limiter.