JP2010194045A - Ultrasonic diagnostic apparatus and transmission unit for ultrasonic diagnostic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To collect good image data by reducing transient responses in driving pulses. <P>SOLUTION: A transmission part 21 of the ultrasonic diagnostic apparatus includes a driving control signal generating part 212 which generates driving control signals Sc1 and Sc2 having prescribed delay times, and a driving pulse generating part 213 which controls switching circuits Sw1 and Sw2 according to the driving control signals and generates bipolar type driving pulses having positive polarity and negative polarity in a secondary-side coil L2 by alternately switching the direction of the electric current flowing in a primary-side coil L1 of a pulse transformer Pt. The ultrasonic diagnostic apparatus generates driving pulses with reduced transient responses by controlling the switching circuits based on the driving control signals composed of basic driving control pulses Po1 and Po2 for generating driving pulses directly contributing to the radiation of ultrasonic pulses and transient response-reducing driving control pulse Pc for reducing the transient responses of the driving pulses. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an ultrasonic diagnostic apparatus and an ultrasonic diagnostic apparatus transmission unit, and more particularly to an ultrasonic diagnostic apparatus and an ultrasonic diagnostic apparatus transmission unit that drive a vibration element using bipolar drive pulses.

  The ultrasonic diagnostic apparatus radiates an ultrasonic pulse generated from a vibration element built in an ultrasonic probe into a subject, and receives an ultrasonic reflected wave caused by a difference in acoustic impedance of a living tissue by the vibration element. It collects various biological information. Recent ultrasonic diagnostic apparatus capable of electronically controlling the transmission / reception direction and focal point of ultrasonic waves by controlling the delay time of drive signals supplied to a plurality of vibration elements and reception signals obtained from the vibration elements. Since real-time image data can be easily observed with a simple operation by simply bringing an ultrasonic probe into contact with the body surface, it is widely used for morphological diagnosis and functional diagnosis of living organs.

  When generating image data of a subject using such an ultrasound diagnostic apparatus, as a driving method for driving an oscillating element provided in the ultrasound probe to emit an ultrasound pulse into the body of the subject Using a driving pulse having a positive polarity and a negative polarity generated in the secondary winding by alternately switching the direction of the current flowing in the primary winding of the pulse transformer using an electronic switching circuit There is a bipolar driving method for driving a vibrating element (see, for example, Patent Document 1).

  FIG. 8 shows a specific configuration of a conventional drive pulse generator 213a composed of a pulse transformer Pt and switching circuits Sw1 and Sw2 for the purpose of generating a bipolar drive pulse, and is supplied to this drive pulse generator 213a. The drive control signals Sc1 and Sc2 are shown. In the drive pulse generator 213a, as shown in FIG. 8, the switching circuit Sw1 connected to the end of the primary winding L1 constituting the pulse transformer Pt and By short-circuiting or opening Sw2 in accordance with the drive control signals S1 and S2 supplied from the drive control signal generator 212a, the DC power supply Vp connected to the center tap of the primary winding L1 is transferred to the primary winding L1. The direction of the incoming current is controlled. The vibration element is driven by a high-voltage drive pulse Px generated at both ends of the secondary winding L2 in accordance with the current flowing through the primary winding L1.

JP 2006-87602 A

  When the bipolar drive pulse Px is generated using the above-described pulse transformer Pt, a transient response component ΔPa is generated at the rear portion of the drive pulse Px generated in the secondary winding L2 of the pulse transformer Pt as shown in FIG. The transient response component ΔPa continues for a period Δτ1 starting from time t3 when the supply of the drive control signal S2 ends. Then, the drive pulse Px including the transient response component ΔPa is supplied to the vibration element provided in the ultrasonic probe, and the ultrasonic pulse is radiated into the body of the subject. It is converted into an electrical reception signal by the vibration element and supplied to the reception unit. That is, the reception signal obtained from the vibration element of the ultrasonic probe is supplied to the reception unit in a state of being superimposed on the transient response component ΔPa of the drive pulse Px.

On the other hand, a limiter circuit that eliminates a pulse component having an amplitude larger than a predetermined threshold value Vs is provided in the preceding stage of the above-described receiving unit in order to protect the receiving unit from the high-voltage drive pulse Px. The limiter circuit eliminates the transient response component ΔPa generated and having an amplitude larger than the threshold value Vs and the reception component superimposed on the transient response component ΔPa. That is, by generating the transient response component ΔPa in the drive pulse Px, it is possible to collect image data in a relatively wide area from the ultrasonic probe corresponding to the duration Δτ1 to the distance ΔR represented by the following equation (1). It had the problem that it was not possible.

  The present invention has been made in view of the above-described problems, and an object thereof is to supply an oscillating element when an oscillating element provided in an ultrasonic probe is driven to emit an ultrasonic pulse to a subject. Another object of the present invention is to provide an ultrasonic diagnostic apparatus and a transmission unit for an ultrasonic diagnostic apparatus that can collect good image data even in the vicinity of the ultrasonic probe by reducing the transient response of the drive pulse.

  In order to solve the above problem, the transmission unit for an ultrasonic diagnostic apparatus according to the first aspect of the present invention is directed to a vibrating element provided in an ultrasonic probe for emitting an ultrasonic pulse into the body of a subject. In a transmission unit for an ultrasonic diagnostic apparatus that supplies a bipolar drive pulse, drive control signal generating means for generating a drive control signal having a predetermined transmission delay time, and generating the drive pulse based on the drive control signal The drive control signal generated by the control signal generator is a basic drive control pulse for generating a drive pulse that directly contributes to the emission of the ultrasonic pulse and a transient of the drive pulse. It is characterized by comprising a drive control pulse for reducing the transient response for reducing the response.

  On the other hand, the ultrasonic diagnostic apparatus of the present invention according to claim 6 radiates an ultrasonic pulse into the body of a subject by driving a vibration element provided in an ultrasonic probe using a bipolar drive pulse, An ultrasonic diagnostic apparatus that generates image data based on an ultrasonic reflected wave obtained from the body, and is generated by the transmission unit for an ultrasonic diagnostic apparatus according to any one of claims 1 to 5. The vibration element is driven using the drive pulse.

  According to the present invention, when a vibration element provided in an ultrasonic probe is driven to emit an ultrasonic pulse to a subject, the ultrasonic probe is reduced by reducing a transient response of the drive pulse supplied to the vibration element. Good image data can be collected even in the vicinity of.

1 is a block diagram showing the overall configuration of an ultrasonic diagnostic apparatus according to an embodiment of the present invention. The block diagram which shows the specific structure of the transmission / reception part with which the ultrasonic diagnosing device of the Example is provided. The figure which shows the specific circuit structure of the drive pulse generation part with which the transmission part of a present Example is provided. The figure which shows the specific circuit structure of the preamplifier with which the receiving part of the Example is provided. The figure for demonstrating the transient response of the drive pulse which generate | occur | produces in the transmission part of the Example. The block diagram which shows the specific structure of the received signal processing part with which the ultrasonic diagnosing device of the Example is provided. The figure which shows the modification of the drive control signal which the drive control signal generation part of a present Example produces | generates. The figure for demonstrating the specific structure of the conventional drive pulse generation part aiming at generation | occurrence | production of a bipolar type drive pulse, and the drive control signal supplied to this drive pulse generation part.

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

  The transmitter included in the ultrasonic diagnostic apparatus of the present embodiment described below includes a drive control signal generator that generates a two-channel drive control signal having a predetermined delay time, and a switching circuit based on the drive control signal. Driving to generate a bipolar driving pulse having a positive polarity and a negative polarity in the secondary winding of the pulse transformer by controlling and alternately switching the direction of the current flowing in the primary winding of the pulse transformer A pulse generator, wherein the drive pulse generator generates a basic drive control pulse for generating a drive pulse that directly contributes to the emission of the ultrasonic pulse generated by the drive control signal generator and a transient response of the drive pulse. The transient response is controlled by controlling the switching circuit based on the drive control signal configured by the drive control pulse for reducing the transient response to reduce the transient response. Gensa the performing generation of driving pulses.

  In the following embodiments, a sector scanning ultrasonic diagnostic apparatus will be described, but an ultrasonic diagnostic apparatus to which a linear scanning method, a convex scanning method, or the like is applied may be used.

(Device configuration)
The configuration of the ultrasonic diagnostic apparatus according to this embodiment will be described with reference to FIGS. However, FIG. 1 is a block diagram showing an overall configuration of the ultrasonic diagnostic apparatus, and FIGS. 2 and 6 are block diagrams showing specific configurations of a transmission / reception unit and a received signal processing unit included in the ultrasonic diagnostic apparatus. It is.

  The ultrasonic diagnostic apparatus 100 of the present embodiment shown in FIG. 1 emits an ultrasonic pulse (transmitted ultrasonic wave) to an imaging region including a diagnostic target part of a subject and obtains an ultrasonic reflection obtained from the diagnostic target part. An ultrasonic probe 3 having a plurality of vibration elements for converting a wave (reception ultrasonic wave) into an electric signal (reception signal), and a driving pulse for radiating a transmission ultrasonic wave to the diagnosis target site And transmitting / receiving unit 2 for phasing and adding received signals of a plurality of channels obtained from these oscillating elements, and B-mode data as ultrasonic data by processing the received signals after phasing and adding. And a reception signal processing unit 4 that generates color Doppler data, and an image data generation unit 5 that generates image data based on the above-described ultrasonic data obtained by ultrasonic scanning on the diagnosis target region. Further, a display unit 6 for displaying image data generated by the image data generation unit 5, an input unit 7 for inputting subject information, setting image data collection conditions, inputting various command signals, and the like, and a transmission / reception unit 2 Are provided with a scanning control unit 8 for controlling the ultrasonic scanning of the diagnosis target part by setting a transmission delay time and a reception delay time, and a system control unit 9 for comprehensively controlling each unit described above.

  The specific configuration and function of each unit provided in the ultrasonic diagnostic apparatus 100 of the present embodiment will be described below.

  The ultrasonic probe 3 in FIG. 1 has N vibrating elements (not shown) at its tip, and each of these vibrating elements is connected to an input / output terminal of the transmission / reception unit 2 via an N-channel multicore cable. ing. The vibration element is an electroacoustic transducer, which converts electrical pulses (drive pulses) into ultrasonic pulses (transmitted ultrasonic waves) during transmission, and converts ultrasonic reflected waves (received ultrasonic waves) into electrical received signals during reception. It has a function to do.

  In the following, in order to simplify the description, a case where N vibration elements provided in the ultrasonic probe 3 are used as a transmission vibration element and a reception vibration element will be described. That is, each of the N transmitting vibration elements is driven by an N-channel driving pulse supplied from the transmission / reception unit 2 to radiate a transmission ultrasonic wave into the subject, and the transmission ultrasonic wave causes the transmission ultrasonic wave to be emitted from within the subject. The obtained reception ultrasonic wave is converted into an N-channel reception signal by the reception vibration element.

  Next, the transmission / reception unit 2 illustrated in FIG. 2 includes a transmission unit 21 that supplies a driving pulse including an N channel for radiating transmission ultrasonic waves to the subject to the transmission vibration element of the ultrasonic probe 3; A receiving unit 22 for performing phasing addition (that is, adding and synthesizing the phases of reception signals corresponding to reception ultrasonic waves from a predetermined direction) of N-channel reception signals obtained from the reception vibration element of the ultrasonic probe 3. I have.

  The transmission unit 21 includes a transmission delay setting unit 211, a drive control signal generation unit 212, and a drive pulse generation unit 213. The transmission delay setting unit 211 transmits transmission ultrasonic waves according to the scanning control signal supplied from the scanning control unit 8. A transmission delay time is set based on a deflection delay time for deflecting in a predetermined direction and a focusing delay time for focusing to a predetermined distance. In this case, the transmission delay time is uniquely determined by the number N of transmission vibration elements, the arrangement interval of the vibration elements, the transmission direction, the transmission focal length, and the like. For example, the transmission delay time may be calculated using an arithmetic circuit (not shown). A variety of delay time data stored in advance as a lookup table may be selected and used.

  On the other hand, the drive control signal generation unit 212 generates drive control signals Sc1 and Sc2 each consisting of N channels based on the transmission delay time information supplied from the transmission delay setting unit 211, and supplies the drive control signals Sc1 and Sc2 to the drive pulse generation unit 213. To do. In this case, the drive control signal Sc1 is a drive control pulse (hereinafter referred to as a basic drive control pulse) for generating a drive pulse that directly contributes to the transmission ultrasonic wave, and a drive generated by the drive pulse generator 213. A drive control pulse (hereinafter referred to as a transient response reduction drive control pulse) for reducing the transient response of the pulse is constituted, and the drive control signal Sc2 is constituted only by the basic drive control pulse. Will be described later.

  Next, a specific circuit configuration of the drive pulse generator 213 will be described with reference to FIG. Each of the drive pulse generators 213 configured of N channels drives the transmitting vibration element provided in the ultrasonic probe 3 based on the drive control signals Sc1 and Sc2 supplied from the drive control signal generation unit 212. And has two-channel switching circuits Sw1 and Sw2 and a pulse transformer Pt as shown in FIG. The center tap co of the primary winding L1 constituting the pulse transformer Pt is connected to the DC power supply Vp, the terminal c1 of the primary winding L1 is connected to the terminal c5 of the switching circuit Sw1, and the primary winding. The other terminal c2 of the line L1 is connected to the terminal c8 of the switching circuit Sw2. Further, the terminal c3 of the secondary side winding L2 constituting the pulse transformer Pt is connected to a transmitting vibration element provided in the ultrasonic probe 3 and a preamplifier 221 described later included in the receiving unit 22, and the secondary side winding L2 is connected. The other terminal c4 is grounded.

  On the other hand, the terminal c5 of the switching circuit Sw1 and the terminal c8 of the switching circuit Sw2 are respectively connected to the terminal c1 and the terminal c2 of the primary winding L1, as described above, and the terminal c6 of the switching circuit Sw1 and the terminal c8 of the switching circuit Sw2 are connected. The terminal c9 is grounded. The control terminal c7 of the switching circuit Sw1 and the control terminal c10 of the switching circuit Sw2 are connected to the output terminal of the drive control signal generation unit 212.

  That is, the switching circuits Sw1 and Sw2 of the drive pulse generator 213 are turned on (short-circuited) by the two-channel drive control signals Sc1 and Sc2 supplied from the drive control signal generator 212 to the control terminals c7 and c10. An OFF (open) state is determined. When the switching circuit Sw1 is short-circuited by the basic drive control pulse Po1 of the drive control signal Sc1 supplied from the drive control signal generation unit 212, the DC power supply Vp passes through the first winding L1 and the switching circuit Sw1. Then, a pulse current i1 flows, and a drive pulse of voltage Vo1 is output between the terminal C3 and the terminal C4 of the second winding L2 along with the pulse current i1.

  On the other hand, when the switching circuit Sw2 is short-circuited by the basic drive control pulse Po2 of the drive control signal Sc2 supplied from the drive control signal generator 212, the DC power supply Vp passes through the first winding L1 and the switching circuit Sw2. Then, a pulse current i2 flows, and a drive pulse of voltage Vo2 (Vo2 = −Vo1) is output between the terminal C3 and the terminal C4 of the second winding L2 along with the pulse current i2.

  Note that the switching circuits Sw1 and Sw2 described above use, for example, N-channel FETs having the same switching characteristics, and alternately open and short during the period in which the drive control signals Sc1 and Sc2 are supplied. In this case, the drain terminal of the FET is connected to the terminal c1 and the terminal c2 in the first winding L1 of the pulse transformer Pt, and the cathode terminal is grounded. Further, the gate terminal of the FET is connected to the output terminal of the drive control signal generation unit 212, and the drain terminal in each FET is based on the drive control signals Sc1 and Sc2 supplied from the drive control signal generation unit 212 to the gate terminal. Opening / short-circuiting with the cathode terminal is performed.

  Returning to FIG. 2, the reception unit 22 of the transmission / reception unit 2 includes an N-channel preamplifier 221 and an A / D converter 222 corresponding to each of the reception vibration elements provided in the ultrasonic probe 3, and a phasing addition unit. 223. The preamplifier 221 is for amplifying the reception signal supplied from the receiving vibration element of the ultrasonic probe 3 to ensure a sufficient S / N. In the first stage, a drive pulse of the transmission unit 21 is generated. A limiter circuit is provided for protecting the preamplifier 221 from a large-amplitude driving pulse generated by the unit 213. The N-channel received signal obtained by the receiving vibration element is amplified to a predetermined magnitude by the preamplifier 221, converted into a digital signal by the A / D converter 222, and then supplied to the phasing adder 223. Is done.

  On the other hand, the phasing addition unit 223 includes a reception delay setting unit and an addition unit (not shown). The reception delay setting unit has a predetermined direction with respect to the N-channel reception signal converted into a digital signal by the A / D converter 222. A reception delay time is set based on a deflection delay time for setting a strong reception directivity and a focusing delay time for focusing a reception ultrasonic wave from a predetermined depth. The adder adds and synthesizes (phased addition) the received signals of the N channels given the reception delay time.

  FIG. 4 shows a specific circuit configuration of the preamplifier 221, and the preamplifier 221 includes a limiter circuit 2211 and an amplifier circuit 2212.

The limiter circuit 221a uses, for example, diodes D1 to D6 and resistors R1 and R2 as shown in FIG. 4, and the input impedance of the preamplifier 221 increases for a signal with a large amplitude such as a drive pulse, and the received signal Such a small amplitude signal is configured to be small.

  That is, the limiter circuit 221a includes a bridge circuit BR configured by diodes D1 to D4 such as a planar diode and a Schottky diode that can withstand a high voltage, and a clamp circuit CL configured by diodes D5 and D6. A positive DC voltage V3 is applied to the anode of the diode D1 and the anode of the diode D3 constituting the bridge circuit BR via the resistor R1. Similarly, a resistance is applied to the cathode of the diode D2 and the cathode of the diode D4. A negative DC voltage V4 (| V4 | = V3) is applied via R2. With such a configuration, the ON resistance for a signal with a small amplitude (reception signal) is lowered by always passing a bias current through the diodes D1 to D4 of the bridge circuit BR.

  On the other hand, one end of the clamp circuit CL configured by connecting two diodes D5 and D6 having different directions in parallel (for example, a connection between the cathode of the diode D5 and the anode of the diode D6) is the output of the bridge circuit BR. The other end (the connection between the anode of the diode D5 and the cathode of the diode D6) is connected to the terminal and grounded.

  With the above-described configuration, the preamplifier 221 exhibits a high input impedance with respect to the large-amplitude driving pulse supplied from the driving pulse generation unit 213 of the transmission unit 21 and has a small amplitude supplied from the vibration element of the ultrasonic probe 3. Presents low input impedance to the received signal. Accordingly, a signal (drive pulse) having an amplitude larger than the threshold value Vs of the diode is clamped, and a signal (received signal) having an amplitude smaller than the threshold value Vs is supplied to the amplifier circuit 221b as it is, so that the amplifier circuit 221b by the drive pulse is used. Can be prevented.

  Next, the transient response of the drive pulse generated in the transmitter 21 will be described with reference to FIG.

  5A and 5B show the drive control signals Sc1 and Sc2 generated by the drive control signal generation unit 212 based on the transmission delay time Δτ set in the transmission delay setting unit 211 of the transmission unit 21. FIG. From the first output terminal of the drive control signal generation unit 212, the basic drive control pulse Po1 having the pulse width τo generated at the time t1 when the transmission delay time Δτ has elapsed from the reference time t0, and the time t1 to 2τo. A drive control signal Sc1 composed of the transient response reduction drive control pulse Pc having the pulse width τc (τc <τo) generated at the time t3 when only elapses.

  On the other hand, the second output terminal of the drive control signal generator 212 outputs the drive control signal Sc2 having the basic drive control pulse Po2 having the pulse width τo generated at time t2 when τo has elapsed from the time t1 described above. The The pulse width τo of the basic drive control pulses Po1 and Po2 described above is set based on the resonance frequency fo of the vibration element provided in the ultrasonic probe 3, and for example, τo = 1 / 2fo.

  Next, FIG. 5C shows the control terminal and switching of the switching circuit Sw1 in which the drive control signal Sc1 of FIG. 5A and the drive control signal Sc2 of FIG. A drive pulse Pcx output from the output end of the pulse transformer Pt (that is, both ends of the secondary winding L2) when supplied to the control terminal of the circuit Sw2 is schematically shown. In this case, as already described in FIG. 8, the basic drive control pulse Po1 of the drive control signal Sc1 having the pulse width τo and the drive pulse Px generated by the basic drive control pulse Po2 of the drive control signal Sc2 include the basic drive. A transient response component is generated in a relatively long period Δτ1 from time t3 when the driving by the control pulse Po2 ends.

  However, as in this embodiment, by driving the drive pulse generator 213 using the transient response reduction drive control pulse Pc having the pulse width τc at the time t3 when the drive by the basic drive control pulse Po2 ends. The transient response component generated by the basic drive control pulses Po1 and Po2 and the transient response component generated by the transient response reduction drive control pulse Pc cancel each other. Therefore, as shown in FIG. 5C, the vibration element of the ultrasonic probe 3 can be driven by the drive pulse Pcx in which the transient response period is significantly shortened.

  FIG. 5D shows the reception signal Sr output from the preamplifier 221 of the reception unit 22 at this time. The reception signal detected by the vibration element is transmitted to the preamplifier 221 in FIG. It is supplied in a state of being superimposed on the drive pulse Pcx. For this reason, the preamplifier 221 having the limiter circuit 2211 receives in the period Δτ2 from the time t3 when the driving by the basic driving control pulse Po2 ends to the time t4 when the transient response component of the driving pulse Pcx attenuates below the predetermined threshold Vs. The signal cannot be received. However, in this embodiment, the transient response period of the drive pulse Pcx is greatly shortened by adding the transient response reduction drive control pulse Pc to the basic drive control pulses Po1 and Po2 to drive the drive pulse generator 213. Therefore, the period Δτ2 during which the received signal cannot be received is significantly shortened as compared with the period Δτ1 shown in FIG. 8, and therefore good image data can be collected even in the vicinity of the ultrasonic probe 3.

  Next, a specific configuration of the received signal processing unit 4 shown in FIG. 1 will be described with reference to the block diagram of FIG. The reception signal processing unit 4 includes a B-mode data generation unit 41 that performs signal processing on the reception signal after phasing addition output from the phasing addition unit 223 of the reception unit 22 to generate B-mode data, and the reception signal Is provided with a color Doppler data generation unit 42 for generating color Doppler data.

  The B-mode data generation unit 41 includes an envelope detector 411 that performs envelope detection on each of the reception signals output from the phasing addition unit 223 of the reception unit 22, and a logarithmic conversion on the reception signal after envelope detection. A logarithmic converter 412 that generates B-mode data by relatively enhancing small signal amplitude by processing is provided.

  On the other hand, the color Doppler data generation unit 42 includes a π / 2 phase shifter 421, mixers 422-1 and 422-2, and LPFs (low-pass filters) 423-1 and 423-2. The reception signal output from the adder 223 is subjected to quadrature detection to generate a complex signal (I signal and Q signal).

  Further, the color Doppler data generation unit 42 includes a Doppler signal storage unit 424, an MTI filter 425, and an autocorrelation calculator 426, and a complex signal obtained by quadrature detection is temporarily stored in the Doppler signal storage unit 424. On the other hand, the MTI filter 425, which is a high-pass digital filter, reads the above-described complex signal stored in the Doppler signal storage unit 424, and performs the respiratory movement of the organ's fixed reflector or organ contained in the complex signal. A Doppler component (clutter component) caused by pulsatile movement or the like is removed. Further, the autocorrelation calculator 426 calculates an autocorrelation value for the Doppler component of the blood flow information extracted by the MTI filter 425, and further, based on the autocorrelation value, an average blood flow velocity value and a variance value The color value Doppler data is generated by calculating the power value and the like.

  Returning to FIG. 1, the image data generation unit 5 includes a B-mode image data generation unit and a color Doppler image data generation unit (not shown), and the B-mode image data generation unit generates the B-mode data of the reception signal processing unit 4. The B-mode image data is generated by sequentially storing the time-series B-mode data generated by the unit 41 in correspondence with the transmission / reception direction of the ultrasonic waves. Similarly, the color Doppler image data generation unit generates color Doppler image data by sequentially storing time-series color Doppler data generated by the color Doppler data generation unit 42 of the reception signal processing unit 4.

  On the other hand, the display unit 6 includes a display data generation unit, a data conversion unit, and a monitor (not shown), and displays B-mode image data and color Doppler image data generated by the image data generation unit 5. For example, the display data generation unit superimposes the B mode image data generated by the B mode image data generation unit of the image data generation unit 5 and the color Doppler image data generated by the color Doppler image data generation unit, and further subjects information Display data is generated by adding incidental information such as. The data converter performs various conversion processes on the display data generated by the display data generator and displays the converted data on the monitor.

  The input unit 7 includes input devices such as a display panel, a keyboard, a trackball, a mouse, a selection button, and an input button on the operation panel. The input unit 7 inputs subject information, sets ultrasonic data collection conditions and image data generation conditions, Further, various command signals are input.

  The scanning control unit 8 performs delay time control for performing ultrasonic scanning on the imaging region including the diagnosis target part of the subject on the transmission delay setting unit 211 of the transmission unit 21 and the phasing addition unit 223 of the reception unit 22. Against.

  On the other hand, the system control unit 9 includes a CPU and a storage circuit (not shown), and the above-described various information input or set by the input unit 7 is stored in the storage circuit. The CPU comprehensively controls each unit of the ultrasound diagnostic apparatus 100 based on the input information and setting information described above, and generates and displays image data for the diagnosis target region of the subject.

  According to the present embodiment described above, when the vibration element provided in the ultrasonic probe is driven to emit an ultrasonic pulse to the subject, the transient response of the drive pulse supplied to the vibration element is reduced. As a result, good image data can be collected even in the vicinity of the ultrasonic probe. For this reason, the diagnostic precision with respect to the diagnostic object site | part located in the vicinity of the body surface can be improved.

  In particular, in the above-described embodiment, it is constituted by a basic drive control pulse for generating a drive pulse that directly contributes to the emission of an ultrasonic pulse and a drive control pulse for reducing a transient response for reducing the transient response of this drive pulse. Since the drive pulse is generated based on the drive control signal, the transient response of the drive pulse can be reduced without complicating the circuit configuration of the drive pulse generator.

  Also, when generating a bipolar drive pulse in the secondary winding of the pulse transformer by controlling the direction of the current flowing in the primary winding of the pulse transformer using a drive control signal comprising two channels, By adding a transient control reducing drive control pulse to any one of the drive control signals described above, a bipolar drive pulse in which the transient response of the drive pulse is greatly reduced can be generated.

Furthermore, according to the above-described embodiment, it is possible to observe the diagnosis target site near the body surface using a normal ultrasonic probe by reducing the transient response of the drive pulse. That is, since the insertion of the coupling medium into the vibration element-body surface, which has been conventionally performed in the diagnosis of a shallow organ, is unnecessary, the operability of the ultrasonic probe is improved, and further, the multiplexing generated in the coupling medium is improved. As described above, the embodiments of the present invention have been described. However, the present invention is not limited to the above-described embodiments, and may be modified and implemented. Is possible. For example, in the above-described embodiments, the sector scanning ultrasonic diagnostic apparatus 100 has been described. However, an ultrasonic diagnostic apparatus to which a linear scanning method, a convex scanning method, or the like is applied may be used.

  In addition, although the case where the vibration element provided in the ultrasonic probe 3 and the transmission / reception unit 2 are connected by an N-channel multicore cable has been described, all or some of the units constituting the transmission / reception unit 2 are It may be built in the ultrasonic probe 3 together with the element.

  Furthermore, although the case where image data is generated based on B-mode data and color Doppler data collected as ultrasonic data has been described, image data can be generated using either B-mode data or color Doppler data. The image data may be generated using other ultrasonic data.

  On the other hand, in the above-described embodiment, the case where the N vibration elements provided in the ultrasonic probe 3 are used as the transmission vibration element and the reception vibration element has been described. An element, a reception-only vibration element, and a transmission / reception vibration element may be selected and used. In this case, the drive pulse supplied to the transmission / reception vibration element is generated by the method described in the above embodiment, but the drive pulse supplied to the transmission-dedicated vibration element or reception-dedicated vibration element may be generated by the same method. Good. In particular, the distance resolution of the entire image data can be improved by driving the transmission-dedicated vibration element and the transmission / reception vibration element using a drive pulse with reduced transient response.

  Further, each of the drive control signals Sc1 and Sc2 in the above-described embodiment has been described as having one basic drive control pulse, but may have a plurality of basic drive control pulses. However, as shown in FIG. 7A, when the drive control signals Sc1 and Sc2 have the same number of basic drive control pulses, the last basic drive control pulse included in the drive control signal Sc2 is the same as in the above embodiment. Subsequently, a drive control pulse Pc for transient response reduction included in the drive control signal Sc1 is supplied to the drive pulse generator 213.

  On the other hand, as shown in FIG. 7B, when the drive control signals Sc1 and Sc2 have different numbers of basic drive control pulses (that is, the number of basic drive control pulses included in the drive control signal Sc1 is equal to the drive control signal Sc2). When the drive control signal Sc1 is one more than the number of basic drive control pulses included), the drive control signal Sc2 includes the drive control pulse Sc for reducing the transient response that is included in the drive control signal Sc2 following the last basic drive control pulse included in the drive control signal Sc1. Supplied to.

2. Transmission / reception unit 21 ... Transmission unit 211 ... Transmission delay setting unit 212 ... Drive control signal generation unit 213 ... Drive pulse generation unit 22 ... Reception unit 221 ... Preamplifier 2211 ... Limiter circuit 2212 ... Amplification circuit 222 ... A / D converter 223 ... phasing addition part 3 ... ultrasonic probe 4 ... reception signal processing part 41 ... B-mode data generation part 42 ... color Doppler data generation part 5 ... image data generation part 6 ... display part 7 ... input part 8 ... scanning control part 9 ... System controller 100 ... Ultrasonic diagnostic apparatus

Claims (6)

In a transmission unit for an ultrasonic diagnostic apparatus that supplies a bipolar drive pulse to a vibration element provided in an ultrasonic probe to emit an ultrasonic pulse into the body of a subject,
Drive control signal generating means for generating a drive control signal having a predetermined transmission delay time;
Drive pulse generating means for generating the drive pulse based on the drive control signal,
The drive control signal generated by the control signal generating means includes a basic drive control pulse for generating a drive pulse that directly contributes to the emission of the ultrasonic pulse and a transient response reduction for reducing a transient response of the drive pulse. A transmission unit for an ultrasonic diagnostic apparatus, characterized in that the transmission unit is constituted by a drive control pulse for use.   2. The transmission unit for an ultrasonic diagnostic apparatus according to claim 1, wherein a pulse width of the transient response reducing drive control pulse constituting the drive control signal is narrower than a pulse width of the basic drive control pulse.   2. The transmission unit for an ultrasonic diagnostic apparatus according to claim 1, wherein the drive control signal generation unit generates the transient response reduction drive control pulse following the plurality of basic drive control pulses.   The drive pulse generating means has a pulse transformer and two switching circuits connected to the end of the primary winding of the pulse transformer, and the drive control signal generated by the drive control signal generating means is switched to the switching circuit. 4. The bipolar drive pulse is generated in the secondary winding of the pulse transformer by alternately supplying to each circuit and switching the current direction of the primary winding. Transmitter unit for ultrasonic diagnostic equipment.   A transmission delay setting means, wherein the transmission delay setting means includes a deflection delay time for deflecting the ultrasonic pulse in a predetermined direction and a focusing delay time for focusing the ultrasonic pulse at a predetermined distance. 2. The transmission unit for an ultrasonic diagnostic apparatus according to claim 1, wherein the transmission delay time is set based on at least one of them. By driving the vibration element provided in the ultrasonic probe using a bipolar drive pulse, an ultrasonic pulse is emitted into the body of the subject, and image data is generated based on the reflected ultrasonic wave obtained from the body. An ultrasonic diagnostic apparatus,
An ultrasonic diagnostic apparatus, wherein the vibration element is driven using a drive pulse generated by the transmission unit for an ultrasonic diagnostic apparatus according to any one of claims 1 to 5.

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