JP2837464B2 - Ultrasonic probe drive - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an ultrasonic probe driving device.

[Conventional technology]

As a conventional ultrasonic diagnostic apparatus, for example, JP-A-58-4540
As disclosed in Japanese Unexamined Patent Application Publication No. H11-207, an electronic linear scan is performed by using a two-dimensional array in which a large number of transducers are arranged in a matrix as ultrasonic transducers, and driving the transducers in a column direction and a row direction alternately. By doing so, it has been proposed to prevent the interference of the sound fields of the transducers in the columns and rows so as to simultaneously obtain ultrasonic images of different tomographic planes.

[Problems to be solved by the invention]

However, in the above-described ultrasonic diagnostic apparatus,
Since the two-dimensional array is used, the characteristics of the transducers are equal. Therefore, it is not suitable for obtaining, for example, an ultrasonic image of the entire pancreas and an ultrasonic image of the pancreas wall from the duodenum.

As an ultrasonic diagnostic apparatus suitable for simultaneously obtaining such different ultrasonic images, for example, a plurality of mechanical scanning ultrasonic probes that transmit and receive ultrasonic waves while rotating ultrasonic transducers having different characteristics are used. Can be considered.

However, in this case, if only a plurality of ultrasonic probes are used, there is a problem that ultrasonic waves projected from the respective ultrasonic probes interfere with each other, and an ultrasonic image with good image quality cannot be obtained. Moreover, when a mechanical scanning ultrasonic probe is used, unlike the above-described two-dimensional array, the ultrasonic diagnostic apparatus does not have a circuit for generating a timing pulse for driving the transducer, and the Since the driving of the vibrator is controlled based on the output of the rotary encoder that detects the rotation angle, the technique using the two-dimensional array described above cannot be applied.

The present invention has been made in view of such a problem, and two ultrasonic probes including at least one mechanical scanning ultrasonic probe are arranged so that their sound fields do not interfere with each other. It is an object of the present invention to provide an ultrasonic probe driving device appropriately configured to be driven so as to obtain an ultrasonic image with good image quality.

[Means and actions for solving the problem]

In order to achieve the above object, an ultrasonic probe driving device according to the present invention includes: a first ultrasonic probe having a first ultrasonic vibrator; and a rotational drive for rotationally driving the first ultrasonic vibrator. Means, a rotation state detection means for detecting a driving state of the rotation drive means, a first reference signal generation means for generating a first reference signal, and the first reference signal generation means generated by the first reference signal generation means. Phase comparison means for comparing the phase of the reference signal of the first and the detection signal detected by the rotation state detection means; rotation control means for controlling the driving of the rotation drive means in accordance with the comparison result by the phase comparison means; A first drive signal generating means for generating a first drive signal for driving the first ultrasonic transducer based on a detection signal of the rotation state detecting means; and a second ultrasonic transducer. Second ultrasonic wave having A lobe, a second reference signal generating means connected to the first reference signal generating means for generating a second reference signal having a phase different from the phase of the first reference signal; And second driving signal generating means for generating a second driving signal for driving the second ultrasonic transducer based on the second reference signal generated by the means. It is assumed that.

Further, an ultrasonic probe driving device according to the present invention includes: a first ultrasonic probe having a first ultrasonic vibrator; a rotation driving unit that rotationally drives the first ultrasonic vibrator; Rotation state detection means for detecting the drive state of the drive means, reference signal generation means for generating a reference signal for setting the rotation state of the rotation drive means, reference signal generated by the reference signal generation means, and the rotation state A rotation control unit that controls driving of the rotation driving unit based on a detection signal detected by the detection unit; and a first ultrasonic transducer that is driven based on a detection signal of the rotation state detection unit. Drive signal generation means for generating a first drive signal for the second, a second ultrasonic probe having a second ultrasonic vibrator, connected to the rotation state detection means, the detection signal Phased And a second drive signal generating means for generating a second drive signal for driving the second ultrasonic transducer based on the signal. It is.

〔Example〕

FIG. 1 shows a first embodiment of the present invention. In this embodiment, two ultrasonic probes 1 and 2 are connected to an ultrasonic diagnostic apparatus 3 to obtain two types of ultrasonic images. The ultrasonic probe 1 is provided with an ultrasonic vibrator 4 rotatably at an insertion end thereof, is driven to rotate by a motor 5 via a flexible shaft 6, and performs radial scanning. The rotation speed and the rotation speed are detected by the rotary encoder 7. Similarly, the ultrasonic probe 2 is provided with an ultrasonic vibrator 8 rotatably at the insertion end thereof, and is rotationally driven by a motor 9 via a flexible shaft 10 to perform radial scanning. The rotation angle and the rotation speed are detected by the rotary encoder 11. Here, the ultrasonic transducers 4 and 8 have different characteristics such as a focal length, a vibration frequency, and an aperture.

The A-phase signal output from the rotary encoder 7 of the ultrasonic probe 1 at each predetermined rotation angle is supplied to the pulser 12 in the ultrasonic diagnostic apparatus 3 and to one input terminal of the phase comparator 13. The other input terminal of the phase comparator 13 is supplied with the output of a reference clock generator 14 for generating a reference clock signal as shown in FIG. 2A, and outputs the output of the phase comparator 13 to a low-pass filter (LPF). ) The current is rectified by the transistor 15 having the characteristic, and the driving of the motor 5 is controlled by the PLL so as to have a speed corresponding to the reference clock signal. Accordingly, the A-phase signal output from the rotary encoder 7 has the same phase as the reference clock signal shown in FIG. 2A, as shown in FIG. 2B.

The A-phase signal output from the rotary encoder 11 of the ultrasonic probe 2 at each predetermined rotation angle is supplied to the pulser 16 in the ultrasonic diagnostic apparatus 3 and the phase comparator 17
To one of the input terminals. A reference clock signal from the reference clock generator 14 is supplied to the other input terminal of the phase comparator 17 by a 90 ° phase shifter 18 with a 90 ° phase shift as shown in FIG. 2C. The output of the circuit 17 is rectified by the transistor 19 having the LPF characteristic in the same manner as described above, and the driving of the motor 9 is controlled by the PLL so that the driving speed becomes a speed corresponding to the reference clock signal. Accordingly, the A-phase signal output from the rotary encoder 11 has the same phase as the output of the 90 ° phase shifter 18 shown in FIG. 2C, as shown in FIG. 2D, and the reference clock signal shown in FIG. In contrast, the phase is shifted by 90 °. Note that the reference clock generator
The frequency of the reference clock signal from 14 can be switched to 1/2, 1/4 or 2 times, 4 times by the scanning line density changeover switch 20, thereby adjusting the scanning line density of the ultrasonic image. To do. Also, 90 ゜ phase shifter
Instead of using 18, the phase of the reference clock signal from the reference clock generator 14 may be shifted by a variable delay line, a shift register, a one-shot multivibrator, or the like.

On the other hand, in the pulser 12, the rotary encoder 7
With the A-phase signal as a trigger, a transmission pulse voltage as shown in FIG. 2E is generated, and this is supplied to the ultrasonic transducer 4 via the slip ring and the cable 21 (not shown) in the ultrasonic probe 1. Then, ultrasonic waves are projected from the ultrasonic transducer 4 into the subject. The ultrasonic wave projected into the subject is received by the ultrasonic transducer 4 and converted into an electric signal, and the echo signal is transmitted through the cable 21, the slip ring and the preamplifier (not shown) into the ultrasonic diagnostic apparatus 3. And demodulates it. The output of the detection circuit 22 is converted into a digital signal by an A / D converter 23, then converted into a required television signal by a digital scan converter (DSC) 24, and supplied to an image display circuit 25. To display an ultrasonic image by the ultrasonic probe 1.

Similarly, in the pulser 16, the rotary encoder
Using the A-phase signal from 11 as a trigger, a transmission pulse voltage as shown in FIG.
Is supplied to the ultrasonic vibrator 8 via a slip ring and a cable 27 (not shown) so that ultrasonic waves are projected from the ultrasonic vibrator 8 into the subject. The ultrasonic wave projected into the subject is received by the ultrasonic vibrator 8 and converted into an electric signal, and the echo signal is transmitted to the ultrasonic diagnostic apparatus 3 via the cable 27, a slip ring and a preamplifier (not shown). And demodulates it. The output of the detection circuit 28 is converted into a digital signal by an A / D converter 29, then converted into a required television signal by a DSC 30, and supplied to an image display circuit 25. The ultrasonic image and the ultrasonic image by the ultrasonic probe 1 are displayed on two screens.

Thus, in this embodiment, the ultrasonic probe
The phases of the reference clock signals for controlling the PLLs of the motors 5 and 9 are different from each other, so that the ultrasonic transducer 4 of the ultrasonic probe 1 and the ultrasonic transducer 8 of the ultrasonic probe 2 are different from each other. Since the driving is performed at different timings, the sound fields do not interfere with each other, so that an ultrasonic image with good image quality can be obtained, and accurate ultrasonic diagnosis can be performed.

FIG. 3 shows a second embodiment of the present invention. In this embodiment, an A-phase signal obtained from the rotary encoder 7 of the ultrasonic probe 1 is supplied to an F / V converter 32 via a frequency divider 31 whose division ratio can be adjusted by a scanning line density changeover switch 20, Here, it is converted into a voltage signal and supplied to one input terminal of the differential amplifier 33. A reference voltage is supplied to the other input terminal of the differential amplifier 33 by a variable voltage generator 34 to obtain a difference from the output voltage of the F / V converter 32, and the difference signal is supplied to the base of a transistor 35. Thus, the collector current is controlled to perform analog proportional control so that the rotation speed of the motor 5 becomes a speed corresponding to the reference voltage set by the variable voltage generator 34. The A-phase signal from the rotary encoder 7 is a 90 ° phase shifter.
The signal is supplied to a phase comparator 17 through an A / P signal 18, where the phase is compared with the A-phase signal obtained from the rotary encoder 11 of the ultrasonic probe 2.
PLL control is performed such that the rotation speed of the motor 9 becomes a speed corresponding to the A-phase signal from the rotary encoder 7, that is, the reference voltage set by the variable voltage generator 34 via the motor 9.
Other configurations are the same as those of the first embodiment.

Therefore, also in this embodiment, as in the first embodiment, the phases of the A-phase signals of the rotary encoders 7 and 11 are different by 90 °, so that the ultrasonic transducers 4 and 8 of the ultrasonic probes 1 and 2 Since they are driven at different timings, sound field interference can be effectively prevented. In this embodiment, the A-phase signal from the rotary encoder 7 is divided by the frequency divider 31. However, the frequency may be multiplied depending on the frequency of the A-phase signal. The A-phase signal from the rotary encoder 7 to be supplied to the phase comparator 17 is a 90 ° phase shifter.
Instead of using 18, the phase may be shifted by a variable delay line, a shift register, a one-shot multivibrator, or the like.

FIG. 4 shows a third embodiment of the present invention. In this embodiment, a mechanical scanning type ultrasonic probe 1 and an electronic scanning type ultrasonic probe 52 are driven. The ultrasonic probe 1 rotates the ultrasonic vibrator 4 while performing PLL control so that the motor 5 rotates at a speed corresponding to the reference clock signal from the reference clock generator 14 in the same manner as described with reference to FIG. Drive is performed based on the A-phase signal (in phase with the reference clock signal) from the encoder 7.

The ultrasonic probe 52 drives the reference clock signal from the reference clock generator 14 by the pulser 16 based on the pulse whose phase is shifted by 90 ° by the 90 ° phase shifter 18. The ultrasonic probe 52 is provided with a plurality of ultrasonic transducers 56 arranged at the distal end thereof.
Is connected to the multiplexer 58 in the ultrasonic diagnostic apparatus 3 via the. Multiplexers 58 are connected to a plurality of delay lines 61 for focusing the ultrasonic waves radiated from the ultrasonic probe 52, and a transmission pulse voltage from the pulser 16 is simultaneously applied to the delay lines 61, and the delay lines 61 61 and a plurality of ultrasonic transducers 56 in the array direction corresponding to the number thereof are sequentially connected by the scanning signal from the scanning signal generator 60 in the multiplexer 58, so that the ultrasonic transducer 56 is Linear or radial scanning is performed, and the received signal is processed by a known signal processing circuit (not shown) via a multiplexer 58 and a delay line 61, and is then transmitted to the monitor 26 along with an ultrasonic image by the ultrasonic probe 4 and an ultrasonic wave by the ultrasonic probe 52. The image is divided and displayed on the screen. The delay line 61 in the ultrasonic probe 52
Is set to be shorter than half the time of the pulse width of the reference clock signal from the reference clock generator 14.

With this configuration, the ultrasonic vibrator 4 of the ultrasonic probe 1 and the ultrasonic vibrator 56 of the ultrasonic probe 52 are alternately driven. Thus, the same effect as in the above-described embodiment can be obtained. In this embodiment, the ultrasonic probe 1 uses the A-phase signal having the same phase as the reference clock signal,
Is driven by a signal obtained by shifting the reference clock signal by 90 °, but the ultrasonic probe 1 is driven by a signal obtained by shifting the reference clock signal by 90 ° and the ultrasonic probe 52 is driven by the reference clock signal. You may make it.

FIG. 5 shows a fourth embodiment of the present invention.
This embodiment also drives the mechanical scanning type ultrasonic probe 1 and the electronic scanning type ultrasonic probe 52, as in the third embodiment.
In the same manner as described in FIG. 3, the rotation speed of the motor 5 is set to a speed corresponding to the reference voltage based on the A-phase signal from the rotary encoder 7 and the reference voltage set by the variable voltage generator 34. The ultrasonic transducer 4 is driven based on the A-phase signal from the rotary encoder 7 while performing analog proportional control, and the ultrasonic probe 52 transmits the A-phase signal from the rotary encoder 7 through the 90 ° phase shifter 18 to the pulser 16. To be driven.

Therefore, also in this embodiment, the drive timing of the ultrasonic transducer 4 of the ultrasonic probe 1 differs from that of the ultrasonic transducer 56 of the ultrasonic probe 52 by 90 ° as in the above-described embodiment. Interference in the sound field can be effectively prevented.

In the above-described embodiment, the ultrasonic images obtained by the two ultrasonic probes are divided and displayed on one monitor 26, but may be displayed on separate monitors.

〔The invention's effect〕

As described above, according to the present invention, two ultrasonic probes including at least one mechanical scanning ultrasonic probe are driven so that their sound fields do not interfere with each other. An ultrasonic image with good image quality can be obtained, and thus accurate ultrasonic diagnosis can be performed.

[Brief description of the drawings]

FIG. 1 is a diagram showing a first embodiment of the present invention, FIGS. 2A to 2F are diagrams showing signal waveforms at various parts thereof, FIG. 3 is a diagram showing a second embodiment of the present invention, FIG. FIG. 5 is a view showing a third embodiment of the present invention, and FIG. 5 is a view showing a fourth embodiment of the present invention. 1,2 ... Ultrasonic probe, 3 ... Ultrasonic diagnostic device 4,8 ... Ultrasonic transducer, 5,9 ... Motor 6,10 ... Flexible shaft 7,11 ... Rotary encoder, 12,16 … Pulsa 13,17… Phase comparator, 14… Reference clock generator 15,19… Transistor, 18… 90 ° phase shifter 20… Scan line density switch, 21,27… Cable 22, 28 Detection circuit, 23, 29 A / D converter 24, 30 DSC, 25 Image display circuit 26 Monitor, 31 Frequency divider 32 F / V converter, 33 Differential amplifier 34 …… Variable voltage generator, 35 …… Transistor 52 …… Ultrasonic probe 56 …… Ultrasonic transducer 58 …… Mux, 60 …… Scanning signal generator 61 …… Delay line

Claims (2)

(57) [Claims] A first ultrasonic probe having a first ultrasonic vibrator; a rotary driving means for driving the first ultrasonic vibrator to rotate; and a rotation detecting a driving state of the rotary driving means. State detection means, first reference signal generation means for generating a first reference signal, and the first reference signal generated by the first reference signal generation means and detected by the rotation state detection means A phase comparison unit that compares a phase with a detection signal; a rotation control unit that controls driving of the rotation driving unit in accordance with a result of the comparison by the phase comparison unit; First
First driving signal generating means for generating a first driving signal for driving the ultrasonic transducer of the first embodiment, a second ultrasonic probe having a second ultrasonic transducer, and the first reference signal A second reference signal connected to the generating means for generating a second reference signal having a phase different from that of the first reference signal;
And a second drive signal for driving the second ultrasonic transducer based on the second reference signal generated by the second reference signal generation means. A driving apparatus for an ultrasonic probe, comprising: a second driving signal generating unit. 2. A first ultrasonic probe having a first ultrasonic vibrator, a rotary driving means for driving the first ultrasonic vibrator to rotate, and a rotation detecting a driving state of the rotary driving means. State detection means, reference signal generation means for generating a reference signal for setting a rotation state of the rotation driving means, reference signal generated by the reference signal generation means, and detection signal detected by the rotation state detection means A rotation control unit that controls the driving of the rotation driving unit based on the first and second rotation driving units;
A first drive signal generating means for generating a first drive signal for driving the ultrasonic vibrator, a second ultrasonic probe having a second ultrasonic vibrator, and the rotational state detecting means. A second drive signal generating means connected to generate a signal having a phase different from the detection signal and to generate a second drive signal for driving the second ultrasonic transducer based on the signal; A driving apparatus for an ultrasonic probe, comprising: