JP4087762B2 - Ultrasonic diagnostic equipment - Google Patents

Description

  The present invention relates to an ultrasonic diagnostic apparatus, and more particularly to signal transmission between a probe head and an apparatus main body.

  In recent years, array transducers have become multi-element. In particular, a 2D array transducer that can electronically scan an ultrasonic beam two-dimensionally includes a plurality of vibration elements. Therefore, it is necessary to insert a large number of signal lines corresponding to these vibration elements in the probe cable, and the probe cable becomes extremely thick, and the operability of the probe is lowered.

  Japanese Patent Application Laid-Open No. H10-228561 discloses a device in which a CCD is provided in a probe head, thereby performing phasing addition in the probe head and transmitting a received signal after phasing addition to the apparatus main body. However, according to this method, the number of signal lines can be surely reduced, but there are various restrictions for the analog phasing addition processing, and it seems that there is a problem in terms of signal quality. In particular, it can be pointed out that it is difficult to cope with a method of simultaneously forming a plurality of reception beams by one transmission and reception.

  Patent Document 2 below converts a plurality of analog reception signals into a plurality of digital reception signals in a probe head, converts them into a serial signal by time-division processing, and transmits it to the apparatus main body. Is disclosed. However, the transfer rate is limited due to the time division processing, and in particular, it is actually very difficult to process received signals from a large number of vibration elements.

JP 2000-33087 A JP 2003-10187 A

  An object of the present invention is to make a probe cable thinner when a large number of vibration elements are provided in a probe head.

  Another object of the present invention is to reduce the number of signal lines even if digital phasing and adding processing is performed in the probe.

  The present invention relates to an ultrasonic diagnostic apparatus having a probe head and an apparatus main body to which the probe head is connected via a probe cable, wherein the probe head includes an array transducer including a plurality of transducer elements, and the array transducer A phasing addition A / D converter for converting a plurality of analog reception signals from a plurality of digital reception signals, and generating a digital phasing addition signal by performing phasing addition processing on the plurality of digital reception signals And a transmission D / A converter for converting the digital phasing addition signal into an analog phasing addition signal, and the apparatus body digitally adds the analog phasing addition signal to the digital phasing addition signal. A transmission A / D conversion unit that converts the signal into a signal, and an image forming unit that forms an ultrasonic image based on the digital phasing addition signal output from the transmission A / D conversion unit. And butterflies.

  According to the above configuration, since digital phasing and adding processing can be performed within the probe head, various advantages resulting from digital processing can be obtained, and particularly good signal quality can be obtained. In addition, signal transmission from the probe head to the apparatus main body is performed as an analog signal, and a large number of signal lines per signal are unnecessary as in the case of parallel transmission with a plurality of bits. That is, one signal line is basically provided for one signal after phasing addition. On the apparatus body side, the digital phasing addition signal is reproduced from the analog phasing addition signal, and the digital phasing addition signal is processed.

  As described above, a plurality of signals are digitally phased and summed in the probe head, and the digital signal generated thereby is analog-transmitted. Both advantages of easy transmission can be enjoyed. The apparatus main body may include a cable connector, and an electronic circuit such as a transmission A / D converter may be provided in the cable connector.

  Preferably, the array transducer is a 2D array transducer in which a plurality of transducer elements are divided into m (where m is an integer equal to or greater than 2) subarrays, A circuit provided corresponding to a sub-array, wherein m sub-phased and summed circuits that perform sub-phased and added processing on the plurality of digital received signals to generate m sub-digital phased and summed signals The transmission D / A conversion unit is configured by m transmission D / A converters that convert the m sub-digital phasing addition signals into m sub-analog phasing addition signals. The A / D converter for transmission is composed of m A / D converters for transmission that convert the m sub-analog phasing / adding signals into m sub-digital phasing / adding signals, The main body further responds to the m sub-digital phased and summed signals. Performing main phase adjusting and summing process Te includes a main phase adjusting and summing unit for generating a main phase adjusting and summing signals.

  According to the above configuration, the sub phasing addition processing is executed for each sub array in the probe head, and m sub digital phasing addition signals generated thereby are transmitted to the apparatus main body as analog signals. On the apparatus body side, the m sub-analog phasing addition signals are converted into digital signals and then subjected to main phasing addition processing, thereby obtaining the main digital phasing addition signals. In this way, the reception beam may be formed by phasing addition processing in several stages.

  Preferably, in the apparatus main body, n main phasing and adding units are arranged in parallel in order to form n (where n is an integer of 2 or more) reception beams by one ultrasonic transmission / reception. Is provided.

  Preferably, n (where n is an integer greater than or equal to 2) reception beams are formed for each transmission / reception of an ultrasonic wave, and the phasing adder is configured to be parallel to the plurality of digital reception signals. There are provided n phasing / adding units for performing n phasing / adding processes to generate n digital phasing / adding signals, and the n digital phasing / adding units are used as the transmission D / A conversion unit. N transmission A / D converters for converting a signal into n analog phasing addition signals are provided, and the n analog phasing addition signals are converted into n transmission phasing and addition signals. There are provided n transmission D / A converters for converting into digital phasing and addition signals.

  According to the above configuration, n digital phasing and addition signals are generated based on a plurality of digital reception signals, and these are transmitted as analog signals to the apparatus body side. Since n pieces of ray information can be obtained by transmitting and receiving ultrasonic waves once, the frame rate or volume rate can be improved.

  Preferably, the probe head includes a transmission unit that supplies a plurality of transmission signals to the array transducer. If the transmission unit is provided in the probe head in this way, it is not necessary to supply the transmission signal of each channel from the apparatus main body side to the probe head, and the probe cable can be reduced in diameter.

  In each of the above configurations, a single circuit that performs time-division operation may be provided instead of a plurality of circuits arranged in parallel. In particular, in the case of a digital phasing and adding circuit or the like, it is possible to easily perform time-division operation on the principle.

  As described above, according to the present invention, there is an advantage that the digital phasing addition can be performed in the probe head and the probe cable can be made thin.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described with reference to the drawings.

  FIG. 1 is a conceptual diagram showing the overall configuration of an ultrasonic diagnostic apparatus according to the present invention.

  This ultrasonic diagnostic apparatus is roughly composed of a probe unit and an apparatus main body 12, and the probe unit is composed of a probe head 10, a probe cable 14, and a cable connector (not shown).

  The probe head 10 is used in contact with the body surface, for example. In the present embodiment, various electronic circuits as shown in FIG. 1 are accommodated in a probe case in the probe head. The probe case has an outer shape to be gripped by the user, and a 2D array transducer 16 described below is disposed on the distal end surface thereof. The 2D array vibrator 16 is formed by two-dimensionally arranging a plurality of vibration elements 16a. An ultrasonic beam is formed by the 2D array transducer 16, and the ultrasonic beam is electronically scanned. Examples of the electronic scanning method include electronic sector scanning. In the present embodiment, the 2D array transducer 16 is composed of, for example, 384 vibrating elements 16a, and the plurality of vibrating elements 16a are divided into 96 subarrays as will be described later. Of course, other configurations can be adopted. For example, the 2D array transducer 16 may be configured by 2000 or 3000 vibrating elements. The 2D array transducer 16 may be a so-called sparse 2D array transducer.

  A transmission / reception control unit 20 is provided in the probe head 10. The transmission / reception control unit 20 receives a control signal from a system control unit 36 (to be described later) in the apparatus main body 12 and controls the operation of each electronic circuit provided in the probe head 10 accordingly. In particular, the transmission / reception control unit 20 performs transmission delay control and reception delay control described below.

  The transmission delay unit 24 includes a plurality of transmitters corresponding to a plurality of transmission channels. Each transmitter may be configured as a circuit that generates a desired transmission waveform, or may be configured as a circuit that simply generates a transmission pulse. The pulsar unit 26 drives a plurality of transmission signals generated by the transmission delay unit 24 with a certain delay relationship, and supplies a plurality of transmission drive signals to the array transducer 16 accordingly. When such a plurality of transmission drive signals are supplied to the plurality of vibration elements 16a constituting the 2D array transducer 16, ultrasonic waves are emitted from the 2D array transducer 16 into the living body, thereby forming a transmission beam. Is done.

  On the other hand, the reflected wave from the living body is received by the 2D array transducer 16. As a result, reception signals as analog signals are output from the plurality of transducer elements 16 a to the A / D conversion unit 28.

  The A / D converter 28 includes a plurality of A / D converters corresponding to a plurality of reception channels, and converts an input reception signal from an analog signal to a digital signal. Incidentally, a preamplifier group or the like may be provided between the 2D array transducer 16 and the A / D converter 28.

  The phasing addition unit 30 is configured as a digital beam former, that is, performs phasing addition processing on a plurality of digital reception signals, thereby generating a signal after phasing addition (digital phasing addition signal). Circuit. In this embodiment, as shown in FIG. 2 later, the phasing adder 30 is configured by a plurality of sub phasing adders, which are arranged in parallel. As described above, when the 2D array transducer 16 is configured by, for example, 384 vibrating elements 16a, they are divided into 96 subarrays, and a sub phase adjusting and adding circuit is provided for each subarray. Each sub phase adjusting and adding circuit executes sub phase adjusting and adding processes for the received signals for four channels.

  The D / A conversion unit 32 is a module that converts the digital phasing addition signal output from the phasing addition unit 30 into an analog phasing addition signal. When a plurality of digital phasing addition signals are output from the phasing addition unit 30, the D / A conversion unit 32 is configured by a plurality of D / A converters corresponding to them. For example, when the digital reception signal output from the A / D conversion unit 28 is configured with 12 bits and the digital phasing addition signal output from the phasing addition unit 30 is configured with 20 bits, the digital adjustment is performed with the same number of bits. When the phase addition signal is supplied to the apparatus main body in parallel, an extremely large number of signal lines are required for each signal. Alternatively, even when time division transmission is performed, extremely high-speed processing is required, and when the number of channels is extremely increased, such time division transmission is also impossible.

  On the other hand, according to the present embodiment, such a multi-bit signal is converted into one analog signal and output, so that the number of signal lines constituting the probe cable 14 can be significantly reduced. It becomes.

  As shown in FIG. 1, the probe cable 14 includes one or a plurality of signal transmission signal lines 34 and a plurality of control lines 22 including a control signal, a clock signal, a power line, and the like. . The control line 22 can be composed of, for example, 10 to 20 lines. Since the probe cable 14 as a whole only needs to have several tens of lines, that is, signal lines, the diameter of the probe cable 14 can be reduced. As a result, it is possible to make the operability of the probe head 10 very good when taking in the three-dimensional echo data, and to reduce the burden on the user.

  Next, the apparatus main body 12 will be described. The system control unit 36 functions as a central control unit and performs operation control of each component in the apparatus main body 12.

  The reception processing unit 38 includes an A / D conversion unit 39 in the present embodiment. The A / D converter 39 is composed of a number of A / D converters corresponding to the number of input analog phasing addition signals. For example, when 96 analog phasing and addition signals are input, 96 A / D converters are provided correspondingly. Thereby, each analog phasing addition signal is restored to a digital phasing addition signal.

  In addition to the A / D conversion unit 39, the reception processing unit 38 includes a main phasing addition unit and the like as necessary. This will be described later with reference to FIG.

  In any case, a phasing addition signal converted into a digital signal is output from the reception processing unit 38, and the beam processing unit 40 performs necessary signal processing on such a signal. For example, for echo signal processing, processing such as gain adjustment and logarithmic compression is performed.

  The image constructing unit 42 is configured by, for example, a digital scan converter (DSC) or the like, and constructs a tomographic image, a three-dimensional image, or the like based on input information for each beam. The ultrasonic image formed thereby is displayed on the display unit 44. Incidentally, the input unit 46 is configured by an operation panel having a keyboard, a trackball, and the like, and data or conditions input thereby are transferred to the system control unit 36.

  Incidentally, when a large number of channels are reduced to, for example, 96 channels as described above, the main phasing addition processing can be performed using the configuration of the conventional ultrasonic diagnostic apparatus as it is. In this case, however, it is necessary to add a program change and control signal output in the system control unit 36.

  FIG. 2 illustrates a specific configuration of the receiving system in the probe head 10 shown in FIG.

  As described above, the 2D array transducer is configured by a plurality of vibrating elements 16a, which are divided into a plurality of subarrays 16b. The sub-array 16b is composed of, for example, four vibration elements 16a, and the four vibration elements form, for example, a square.

  The preamplifier group 50 includes a preamplifier 50a provided for each vibration element 16a. Similarly, the A / D converter 28 includes an A / D converter 28a provided for each vibration element 16a. .

  The phasing / adding unit 30 includes a plurality of sub phasing / adding circuits 51 provided for each sub-array 16a. That is, the first-stage phasing addition is performed on the four received signals in the subarray 16a. As shown in FIG. 2, the sub phase adjusting and adding circuit 51 includes a plurality of delay circuits 52 and an adding circuit 54 for adding the outputs. The delay circuit 52 is a circuit that gives a delay time to an input signal as illustrated later with reference to FIG. The D / A converter 32 includes a D / A converter 32a provided for each subarray 16a.

  On the other hand, when the circuit configuration shown in FIG. 2 is adopted, the reception processing unit 38 in the apparatus main body 12 has the configuration shown in FIG. That is, the A / D conversion unit 39 is configured by a plurality of A / D converters 39a provided for each subarray, and one main phasing addition circuit 56 is provided at the subsequent stage thereof. The main phasing / adding circuit 56 includes a plurality of delay circuits 58 for performing delay processing on the digital phasing / adding signal output for each subarray, and an adding circuit 60 for adding the outputs of the delay circuits. The From the adding circuit 60, the main phasing addition signal is output as a digital signal.

  FIG. 4 shows a configuration example of the delay circuit 52 shown in FIG. 2 and the delay circuit 58 shown in FIG. The input signal is input to the line memory 64 through a low pass filter (LPF) 62. Writing and reading of data in the line memory 64 is controlled by a delay controller 66. The delay controller 66 reads a signal from the line memory 64 at a predetermined timing according to the delay time set in the delay memory 68 especially when reading data. The read signal is output to the interpolation circuit 70. The interpolation circuit 70 performs an interpolation process to adjust the delay time of the input signal to a very small amount (decimal part), and thereby a delay time corresponding to the delay data set in the delay memory 68. A signal delayed by this amount is output.

  Incidentally, it is also possible to perform delay processing on a plurality of signals by one circuit by performing the time division operation on the circuit configuration shown in FIG. This is also an advantage of the digital beam former.

  5 and 6 show a modified example related to the above configuration.

  In the example shown in FIG. 5, a plurality of phasing adders 30 are provided in parallel at the subsequent stage of the A / D converter 28 in the probe head. Each phasing adder 30 executes a plurality of phasing addition processes in parallel in order to simultaneously form a plurality of reception beams per transmission / reception. A plurality of D / A converters 32 a are provided at the subsequent stage of the phasing adder 30. Therefore, according to the configuration shown in FIG. 5, it is possible to perform a process of electronically forming a plurality of reception beams in the probe head 10, and a plurality of phasing addition signals obtained as a result are converted into analog signals. 12 can be transmitted.

  In the example shown in FIG. 6, on the assumption that the configuration shown in FIG. 2 is adopted, a plurality of main phasing and adding circuits 56 are provided in parallel in the apparatus main body. That is, a plurality of main phasing and adding circuits 56 are provided in parallel with each other at the subsequent stage of the A / D conversion unit 38, and each main phasing and adding circuit 56 is provided with a plurality of sub-arrays. A second phasing addition process is performed on the sub phasing addition signal, thereby generating a main phasing addition signal. This makes it possible to electronically form a plurality of reception beams per transmission / reception. In this case, a plurality of sub phase adjusting and summing circuits in the probe head are shared by each reception beam.

  In the above embodiment, if a clock generator is provided in the probe head 10, it is not necessary to supply a clock signal from the apparatus main body side. In general, since the synchronization signal and the control signal supplied from the apparatus body side are state signals, the problem of noise with respect to the received signal is solved or reduced. Although various numerical values have appeared in the above-described embodiment, they are merely examples, and various numerical values can be adopted.

  When an analog signal is transmitted from the probe head 10 to the apparatus main body 12, the analog signal may be a voltage signal or a current signal.

1 is a conceptual diagram showing an overall configuration of an ultrasonic diagnostic apparatus according to the present invention. It is a circuit diagram which shows the specific example of the receiving system in the probe head shown in FIG. It is a block diagram which shows the structural example of the reception process part in the apparatus main body shown in FIG. FIG. 4 is a block diagram illustrating a configuration example of a delay circuit illustrated in FIGS. 2 and 3. It is a figure which shows the example of a circuit structure for forming a several receiving beam simultaneously. It is a figure which shows the other circuit structural example for forming simultaneously a some receiving beam.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 Probe head, 12 Apparatus main body, 14 Probe cable, 16 2D array vibrator | oscillator, 28 A / D conversion part, 30 Phased addition part, 32 D / A conversion part, 38 Reception processing part, 39 A / D conversion part.

Claims (5)

In an ultrasonic diagnostic apparatus having a probe head and an apparatus main body to which the probe head is connected via a probe cable,
The probe head is
An array vibrator comprising a plurality of vibration elements;
A phasing addition A / D converter for converting a plurality of analog reception signals from the array transducer into a plurality of digital reception signals;
A phasing addition unit that generates a digital phasing addition signal by performing phasing addition processing on the plurality of digital reception signals;
A D / A converter for transmission for converting the digital phasing addition signal into an analog phasing addition signal;
Including
The apparatus main body is
An A / D converter for transmission that converts the analog phasing addition signal into a digital phasing addition signal;
An image forming unit that forms an ultrasonic image based on the digital phasing addition signal output from the A / D conversion unit for transmission;
An ultrasonic diagnostic apparatus comprising: The apparatus of claim 1.
The array transducer is a 2D array transducer in which the plurality of transducer elements are divided into m (where m is an integer of 2 or more) sub-arrays,
The phasing / adding unit is a circuit provided corresponding to the m subarrays, and performs subphasing / addition processing on the plurality of digital reception signals to generate m subdigital phasing / addition signals. Is composed of m sub-phasing and adding circuits,
The transmission D / A converter is composed of m transmission D / A converters that convert the m sub-digital phasing addition signals into m sub-analog phasing addition signals,
The transmission A / D conversion unit includes m transmission A / D converters that convert the m sub-analog phasing addition signals into m sub-digital phasing addition signals,
The apparatus main body further includes at least one main phasing addition unit that performs main phasing addition processing on the m sub-digital phasing addition signals to generate a main phasing addition signal. Ultrasound diagnostic device. The apparatus of claim 2.
The apparatus main body is provided with n main phasing / adding units in parallel in order to form n (where n is an integer of 2 or more) reception beams by one ultrasonic transmission / reception. An ultrasonic diagnostic apparatus characterized by that. The apparatus of claim 1.
N (where n is an integer of 2 or more) receive beams are formed for each transmission / reception of an ultrasonic wave,
As the phasing and adding unit, n phasing and adding units that perform n phasing and adding processes in parallel on the plurality of digital reception signals to generate n digital phasing and adding signals are provided. ,
As the transmission D / A converter, n transmission A / D converters for converting the n digital phasing addition signals into n analog phasing addition signals are provided,
As the transmission A / D converter, n transmission D / A converters for converting the n analog phasing addition signals into n digital phasing addition signals are provided.
An ultrasonic diagnostic apparatus. The apparatus of claim 1.
The ultrasonic diagnostic apparatus, wherein the probe head includes a transmission unit that supplies a plurality of transmission signals to the array transducer.

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