JP2987723B2 - Ultrasound diagnostic equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic diagnostic apparatus, and more particularly to an ultrasonic diagnostic apparatus having an ultrasonic probe having an acoustic lens.

[0002]

2. Description of the Related Art When an ultrasonic probe is left in the air for a long time, the ultrasonic probe generates heat because the vibration energy of the piezoelectric element is not released, thereby deteriorating the characteristics.

In order to prevent this, for example, Japanese Patent Application Laid-Open
An ultrasonic diagnostic apparatus disclosed in JP-A-122429 has been proposed. In the ultrasonic diagnostic apparatus disclosed in JP-A-63-122429, as shown in FIG. 7, a signal waveform a received when an ultrasonic probe is applied to a living body is shown in FIG.
Then, while the signal level is large in both the sample period g1 and the sample period g2, in the signal waveform b received when the ultrasonic probe is left in the air, the signal level in the sample period g2 is smaller than the signal level in the sample period g1. It is determined whether or not the ultrasonic probe is left in the air by paying attention to the point that the signal level becomes extremely small. And
When it is determined that the ultrasonic probe is left in the air, the driving of the ultrasonic probe is interrupted.

[0004]

In the conventional ultrasonic diagnostic apparatus described above, it is determined whether or not the ultrasonic probe is left in the air by paying attention to the signal levels in the sample periods g1 and g2. However, if the portion corresponding to the sample period g1 is the living tissue and the portion corresponding to the sample period g2 is the water inside the living body even when the ultrasonic probe is applied to the living body, the received signal waveform is as shown in FIG. The waveform becomes like the signal waveform d, and it is erroneously determined that the ultrasonic probe is left in the air. That is, there is a problem that it is not reliable to determine whether the ultrasonic probe is left in the air.

An object of the present invention is to provide an ultrasonic diagnostic apparatus which accurately determines whether an ultrasonic probe is left in the air and controls the transmission of the ultrasonic probe.

[0006]

According to the ultrasonic diagnostic apparatus of the present invention, there is provided an ultrasonic diagnostic apparatus having an ultrasonic probe having an acoustic lens. And a transmission control means for controlling the transmission of the ultrasonic probe according to the output of the reflection detection means.

[0007]

When an ultrasonic probe having an acoustic lens such as rubber is applied to a living body, the ultrasonic wave travels in the living body without causing multiple reflection of the ultrasonic wave in the acoustic lens. However, when left in the air, multiple reflections of ultrasonic waves occur in the acoustic lens. Therefore, in the ultrasonic diagnostic apparatus of the present invention, the reflection of the ultrasonic wave by the acoustic lens is detected by the reflection detecting means, and it is determined whether or not the ultrasonic probe is left in the air. When it is determined that the ultrasonic probe is left in the air, the transmission of the ultrasonic probe is interrupted or suppressed by the transmission control unit.

As described above, since attention is paid to the reflection of the ultrasonic wave from the acoustic lens, it is possible to accurately determine whether or not the ultrasonic probe is left in the air.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in more detail with reference to the embodiments shown in the drawings. It should be noted that the present invention is not limited by this. FIG. 1 is a main block diagram of an ultrasonic diagnostic apparatus according to one embodiment of the present invention.

In the ultrasonic diagnostic apparatus 1, the transmission beamformer 3 transmits an ultrasonic wave from the ultrasonic probe 4 in synchronization with a system trigger generated by the system trigger generator 2. The ultrasonic echo signal is received by the ultrasonic probe 4, and is input to the DSC 7 via the reception beamformer 5 and the filter logarithmic compression unit 6. Then, an image is generated by the DSC 7 and displayed on the CRT 8.

The waveform shaping section 10 is a filter circuit for removing ringing and noise from the output signal of the filter logarithmic compression section 6 and extracting only a portion having a high signal level.
The gate signal generator 11 is provided with the system trigger generator 2
"H" for a predetermined period from the system trigger signal where
Output the gate signal. Further, the predetermined time is adjustable so that multiple reflection of ultrasonic waves by the acoustic lens can be detected. The pulse generating unit 12 outputs a pulse when the output signal of the waveform shaping unit 10 becomes higher than a predetermined level when the gate signal is “H”.

The pulse interval determination unit 13 measures the interval between the pulses, and when three or more pulses are consecutive at equal intervals, determines that the ultrasonic probe 4 is left in the air and transmits the ultrasonic probe 4 to the transmission beam former 3. Output the wave suppression signal. on the other hand,
When three or more pulses continue at irregular intervals, the ultrasonic probe 4
Is determined to have hit the living body, and the output of the transmission suppression signal to the transmission beam former 3 is stopped.

The transmission beam former 3 transmits the ultrasonic waves from the ultrasonic probe 4 in synchronization with the system trigger as described above while the transmission suppression signal is not input. Is input, the ultrasonic wave is transmitted from the ultrasonic probe 4 in synchronization with the system trigger once every 100 times, and the remaining 99 times are paused. In addition, 1
It may be once per frame.

The ultrasonic probe 4, the receiving beamformer 5, the filter logarithmic compressing unit 6, the waveform shaping unit 10, the gate signal generating unit 11, the pulse generating unit 12, and the pulse interval determining unit 13 constitute a reflection detecting means. The transmission beamformer 3 constitutes a transmission control unit.

FIG. 2 shows a state in which the ultrasonic probe 4 is applied to a living body. The ultrasonic wave is emitted from the piezoelectric ceramics 4a, passes through the matching film 4b and the rubber lens 4c, and travels into the living body F as indicated by α in FIG. At this time, the signal A as shown in FIG. 3 is input to the waveform shaping unit 10, and the signal B as shown in FIG. When the signal B as shown in FIG. 3 becomes larger than a predetermined level T when the gate signal C as shown in FIG. 3 is "H", the pulse generator 12 outputs a pulse of the signal D as shown in FIG. . Pulse interval determination unit 1
3, when the signal D of FIG. 3 is input, the pulse intervals P1,
Since P2 is not equal, no transmission suppression signal is output. Therefore, the transmission beamformer 3 transmits an ultrasonic wave from the ultrasonic probe 4 in synchronization with a system trigger.

FIG. 4 shows a state where the ultrasonic probe 4 is left in the air. The ultrasonic wave is shown in FIG.
As indicated by α2, the light is multiple-reflected by the rubber lens 4c.
At this time, the signal A as shown in FIG. 5 is input to the waveform shaping unit 10, and the signal B as shown in FIG. When the signal B as shown in FIG. 5 becomes larger than a predetermined level T when the gate signal C as shown in FIG. 5 is "H", the pulse generator 12 outputs a pulse of the signal D as shown in FIG. . When the signal D in FIG. 5 is input, the pulse interval determination unit 13 outputs a transmission suppression signal because the pulse intervals P1, P2, and P3 are equal. Therefore, the transmission beamformer 3 transmits an ultrasonic wave from the ultrasonic probe 4 in synchronization with the system trigger once every 100 times,
It has been dormant nine times. Therefore, heat generation of the ultrasonic probe 4 is suppressed. The transmission of the ultrasonic wave from the ultrasonic probe 4 only once every 100 times of the system trigger is performed by detecting that the ultrasonic probe 4 has been applied to the living body again, stopping the output of the transmission suppression signal, and This is to automatically return to the state.

The level T is set, for example, to a level at which a signal based on the fourth multiple reflection can be exceeded.

Another embodiment is one in which the transmission beamformer 3 lowers the transmission power by the transmission suppression signal.

As still another embodiment, as shown in FIG. 6, the period when the gate signal C is "H" is set to the first and / or
Alternatively, it is set short enough to receive the signal based on the second multiple reflection, and when the signal B input during that period exceeds a predetermined level T, the pulse interval determination unit detects the multiple reflection by the acoustic lens. Things.

[0020]

According to the ultrasonic diagnostic apparatus of the present invention, the state in which the ultrasonic probe is left in the air can be accurately detected. In addition, since the transmission from the ultrasonic probe is controlled thereby, heat generation and characteristic deterioration can be reliably prevented.

[Brief description of the drawings]

FIG. 1 is a main block diagram of an embodiment of an ultrasonic diagnostic apparatus according to the present invention.

FIG. 2 is an explanatory diagram of a state where an ultrasonic probe is applied to a living body.

FIG. 3 is a waveform diagram of a signal of each unit of the apparatus of FIG. 1;

FIG. 4 is an explanatory diagram of a state where an ultrasonic probe is left in the air.

FIG. 5 is a waveform diagram of a signal of each unit of the apparatus of FIG. 1;

FIG. 6 is a waveform diagram of a signal according to still another embodiment of the ultrasonic diagnostic apparatus of the present invention.

FIG. 7 is an explanatory diagram of a principle of determining a state where an ultrasonic probe is left in the air in a conventional ultrasonic diagnostic apparatus.

FIG. 8 is a waveform diagram of a signal according to a conventional ultrasonic diagnostic apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ultrasonic diagnostic apparatus 3 Ultrasonic beam former 4 Ultrasonic probe 4c Rubber lens 10 Waveform shaping part 11 Gate signal generating part 12 Pulse generating part 13 Pulse interval judging part

Claims (1)

(57) [Claims] 1. An ultrasonic diagnostic apparatus comprising an ultrasonic probe having an acoustic lens, a reflection detecting means for detecting reflection of ultrasonic waves by the acoustic lens, and a transmission of the ultrasonic probe in accordance with an output of the reflection detecting means. An ultrasonic diagnostic apparatus comprising: a transmission control unit configured to control a wave.