JPH0295355A - Transducer driver for ultrasonic diagnostic device - Google Patents

Abstract

(57) [Abstract] 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 a transducer drive device for an ultrasonic diagnostic apparatus, and particularly to a method for controlling the frequency band of emitted ultrasonic waves.

[Conventional technology]

Ultrasonic diagnostic equipment is generally used in the medical field to diagnose the heart, circulatory system, etc.; is measured, and this distribution is displayed on the CRT in the same way as above.

This ultrasonic diagnostic device includes a probe having a transducer for sending and receiving, and a diagnostic device main body to which the probe is connected. The transducer provided in the probe converts an electric signal into an ultrasonic signal or an ultrasonic signal into an electric signal.

That is, an impulsive drive voltage (pulse) is applied to the transducer, which causes the transducer to output an ultrasonic signal. This ultrasound signal is transmitted into the living body, and reflected ultrasound echoes from the living body are received by the transducer. The transducer is
This reflected ultrasonic echo is converted into an electrical signal and input into the main body of the diagnostic apparatus, where various signal processing is performed.

At this time, the transducer has a natural frequency, and therefore, in order to efficiently obtain an ultrasonic signal, it is necessary to apply a drive voltage with an appropriate waveform to the transducer used.

[Problem to be solved by the invention]

As described above, an impulse-like drive voltage, that is, a drive voltage having a wide frequency distribution is applied to the transducer to widen the band of the ultrasonic signal and improve the distance resolution.

However, even if the frequency distribution of the driving voltage becomes wideband, the waveforms of the emitted ultrasonic signals and reflected echoes will be vibratory and not short due to the inherent resonance characteristics of the transducer itself. , the distance resolution may be poor.

Furthermore, when an ultrasound signal enters a living body, the higher the frequency, the greater the attenuation. Therefore, if you try to apply an impulse drive voltage to the transducer and improve the deep S/N, you will need a higher drive voltage, which will make the configuration of the power supply difficult, and the transducer The problem is the pressure resistance.

Furthermore, in an ultrasonic diagnostic apparatus, a multi-stage focusing method is sometimes used in order to obtain images with good resolution over the entire region from a shallow region to a deep region. When implementing this multi-stage focusing method, taking into consideration the attenuation characteristics of ultrasonic waves as described above, the frequency should be increased for shallow areas to obtain clearer images, and the frequency should be lowered for deep areas. There are cases where it is desired to change the frequency distribution of the ultrasound signal depending on the focus position so that the ultrasound signal reaches that part.

This invention has been made in view of the above points, and it is possible to obtain ultrasonic signals and their reflected echoes with optimum efficiency for various probes without increasing the driving voltage, and also to adapt to the diagnostic field of view. An object of the present invention is to obtain a transducer drive device for an ultrasonic diagnostic apparatus that can change the frequency distribution of an ultrasonic signal.

[Means to solve the problem]

A transducer drive device for an ultrasound diagnostic apparatus according to the present invention includes a waveform data storage means for storing a drive voltage waveform of a transducer, a waveform data selection means, a waveform data reading means, and a transducer drive means. It has been established.

The waveform data storage means stores a large number of drive voltage waveforms, and the waveform data selection means selects one of the stored waveform data to be applied to the transducer in response to an external instruction. Select the desired driving voltage waveform. Further, the waveform data reading means reads data of the drive waveform selected by the waveform data selection means from the waveform data storage means, and the transducer drive means uses the waveform data of the read drive voltage. drive the transducer based on the

[Effect]

In this invention, data of a large number of voltage waveforms for driving the transducer is stored in a storage means such as a memory. Then, an optimal waveform is selected from among the large number of drive voltage waveforms depending on the transducer used and the diagnostic field of view. This selection is performed by a computer or the like, and the data of the voltage waveform selected as 0 is read out by a reading means constituted by an address control circuit or the like, and the transducer is driven based on the read data.

Thereby, the transducer can be driven with an optimal voltage waveform depending on the transducer used, and the necessary band of the ultrasonic signal can be extracted without loss.

Furthermore, when adopting a multi-stage focusing method, by selecting the drive voltage waveform of the transducer according to each focus position, the frequency distribution can be changed according to the diagnostic field of view. For example, clear images can be obtained in shallow areas, and ultrasonic signals can also be transmitted to deep areas for diagnosis.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a schematic configuration diagram of a transducer drive circuit according to an embodiment of the present invention. In the figure, 1a to 1n are transducer elements (micro oscillators), and each of these transducer elements 1a to In (hereinafter simply referred to as transducer) is a driving amplifier 2.
It is connected to delay lines 3a to 3n having different delay amounts via a to 2n.

Further, 5 is a waveform data storage device that stores a large number of voltage waveform data for driving the transducer, and 6 selects one of the large number of waveform data stored in this waveform data storage device 5. This is a waveform data selection device that selects the waveform data in response to instructions from a control device 7 made up of a computer or the like. Also, 8
Reference numeral 9 denotes a waveform data readout circuit that reads out the selected waveform data by inputting a firing trigger pulse, and 9 a readout clock generation circuit that provides a readout clock to the waveform data readout circuit 8.

Further, IO is a D/A conversion circuit that converts digital data read from the waveform data storage device 5 into analog data that can drive the transducer. In this way, the D/A conversion circuit 10. delay lines 3a to 3n,
The drive amplifiers 2a to 2n constitute a drive means for the transducer.

FIG. 2 shows an example of the waveform data stored in the waveform data storage means 5, and the areas (■, ■, ■, . . . ) each contain different drive voltage waveforms as shown in the figure. Data is stored.

Next, the operation will be explained.

When the firing trigger pulse is input to the waveform data readout circuit 8, a signal from the readout clock generation circuit 9 of, for example, 20MHz is generated.
According to the read clock, the waveform data read circuit 8 outputs address data.

Here, the address data for reading the waveform data is, for example, the upper n bits (n is set according to the number of drive waveform data to be selected), the lower 6 bits (one set of drive waveform data consists of 64 bits) Suppose that it is composed of data). Then, the control device 7 outputs a control signal to the waveform data selection circuit 6 so that the drive voltage waveform most suitable for the characteristics of the transducer to be used is selected, and the waveform data selection circuit 6 selects the drive waveform data to be used. Outputs the corresponding upper address. On the other hand, each data in the area selected by the upper address data is read out by the lower address data from the waveform data reading circuit 8.

As mentioned above, when a 20 MHz read clock is used, its cycle is 50 ns, and a 3.2 μs drive pulse waveform is output as digital data from the waveform data storage device 5 as one set of data. This data is converted into analog data by the D/A conversion circuit 10. Then, as in the conventional case, the signal is input to each delay line 3a to 3n and applied to the transducers 1a to 1n via drive amplifiers 2a to 2n.

In addition, when this embodiment is used in a multi-stage focusing method,
Programming is performed so that the optimum drive voltage waveform is selected depending on the focus position. For example, when the focus position is shallow, a drive waveform that emphasizes high frequencies is selected to make the image clearer, and when the focus position is deep, the drive waveform is selected to emphasize low frequencies so that the ultrasound waves reach that area. A driving waveform is selected.

In this embodiment, an optimal drive voltage waveform can be selected depending on the transducer used, and ultrasonic waves in a necessary band can be efficiently extracted without increasing the drive voltage. In addition, for example, it can be applied to a multi-stage focusing method to change the frequency distribution depending on the diagnostic field of view.
More accurate diagnosis can be performed.

〔Effect of the invention〕

As described above, according to the present invention, a large number of drive voltage waveforms of transducers are stored, and the drive voltage waveform is appropriately selected depending on the transducer used, so that the drive voltage waveform is always optimal. The transducer can be driven with a voltage waveform, and the required band of the ultrasound signal can be extracted without loss.Also, the drive voltage of the transducer can be changed according to the diagnostic field of view, and the frequency distribution of the ultrasound signal can be adjusted. can be changed depending on the depth of the site to be diagnosed.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a transducer driving device according to an embodiment of the present invention, and FIG. 2 is a diagram showing the stored contents of a memory included in the circuit. la~1n...Transducer element, 2a~
2n...Drive amplifier, 3a-3n...Delay line, 5.
... Waveform data storage device, 6... Waveform data selection circuit, 7... Control device, 8... Waveform data reading circuit, 1
0...D/A conversion circuit. Billet ・Brim ・】～

Claims (1)

[Claims] (1) A transducer drive device for applying a predetermined drive voltage to a transducer that generates ultrasonic waves, which includes waveform data storage means for storing a large number of drive voltage waveforms for driving the transducer, and a waveform data storage means for storing a large number of drive voltage waveforms for driving the transducer; waveform data selection means for selecting drive voltage waveform data stored in the waveform data storage means in response to an instruction; and waveform data reading means for reading out the waveform data selected by the waveform data selection means from the waveform data storage means. A transducer driving device for an ultrasonic diagnostic apparatus, comprising: a driving means for applying a driving voltage to the transducer based on the read waveform data.