JPWO2016143133A1 - Ultrasonic probe, method for adjusting ultrasonic probe, and ultrasonic diagnostic apparatus - Google Patents

Abstract

In a multi-channel transducer probe, in order to reduce reception gain variation between channels, a transducer, a transmission circuit for transmitting a signal for driving the transducer with ultrasonic waves, and a signal transmitted from the transmission circuit Correct the capacitance of the line including the wiring that transmits the signal from the vibrator driven by ultrasonic waves, the receiving circuit that connects to the wiring and receives the signal from the vibrator, and the wiring from the vibrator to the receiving circuit The combination with the capacitance correction circuit is one channel, and an ultrasonic probe is configured with multiple channels, and the capacitance of the line including the wiring from the transducer to the receiving circuit is measured for each channel. The capacity correction circuit was adjusted for each channel so that the measured capacity of the channels was the same.

Description

  The present invention relates to an ultrasonic probe, an adjustment method of an ultrasonic probe, and an ultrasonic diagnostic apparatus.

  With the increase in the number of channels of transducers incorporated in the probe of the ultrasonic diagnostic apparatus, control for each channel is performed on the receiving circuit of the ultrasonic diagnostic apparatus. Japanese Patent Application Laid-Open No. H10-228688 describes that a CPU (Central Processing Unit) corresponding to the number of channels of the vibrator is provided, and that the disturbance of the diagnostic image is corrected by processing the received signal.

  Patent Document 2 discloses a signal correction technique for a touch sensor having a plurality of operation pads as a technique for correcting a received signal of a printed wiring board on which elements of a plurality of channels are mounted.

Japanese Patent Laid-Open No. 11-9594 JP 2012-95180 A

  By the way, it has been found that the wiring length and the wiring width of the printed wiring board in the connection between the multi-channel ultrasonic transducer and the receiving circuit cause variations in the reception gain of the echo signal between channels.

FIG. 9 shows an example of a probe substrate of a multi-channel ultrasonic transducer.
FIG. 9 is a diagram showing a state of wiring connecting the transducer and the transmission / reception circuit and the transducer and the transmission / reception circuit of the ultrasonic probe, and wiring connecting the transmission / reception circuit and the transducer arranged near the transducer. 2 is a plan view of an ultrasonic probe showing a state in which the length of the wire is different from the length of the wiring connecting the transmission / reception circuit and the transducer arranged far from the transducer.

  910 is a probe substrate, 911 is a vibrator, 9124 to 9128 are receiving circuits of channel 4 to channel 8, and 9151 to 915n are wirings for connecting the receiving circuit and the vibrators 9111 to 911n.

  As shown in the figure, the wiring 9156 that connects the receiving circuit 9126 and the vibrator arranged close to the vibrator is short, so the wiring parasitic capacitance Cp is small, but the receiving circuit 9128 that is arranged far from the vibrator and the vibrator are connected. Since the wiring 9158 is long, the wiring parasitic capacitance Cp is large.

  This wiring parasitic capacitance Cp is expressed by (Equation 1), and the output signal of the ultrasonic transducer is affected by this Cp. Therefore, if the variation in Cp is large, the reception gain varies.

  Conventionally, when the receiving circuit far from the transducer, that is, the wiring length is long, the wiring width W is narrowed, and when the receiving circuit near the transducer, that is, the wiring length is short, the wiring width W is increased to make the area L × W constant. It was close to the value to suppress variations.

However, with the recent increase in the number of transducer channels, it is difficult to manufacture a printed wiring board while maintaining a large number of receiving circuits at a constant value of L × W, and a glass epoxy board that is an inexpensive printed wiring board Has a manufacturing tolerance in the wiring width W and the dielectric layer thickness d, and thus there is a problem that variations remain.
Cp = εr × (L × W) / d (Equation 1)
L: Wiring length W: Wiring width d: Dielectric thickness εr: Dielectric relative permittivity In the invention described in Patent Document 1 for this problem, the received signal can be controlled for each channel of the vibrator. However, since the channel-to-channel variation included in the transducer output is not corrected, the signal processing is performed with the variation included, and the influence of the variation cannot be removed.

  In the invention described in Patent Document 2, the glass-sensor distance of the touch sensor is corrected by correcting reception signals from a plurality of operation pads based on the output signal of the adjustment pad. As for, individual variation for each touch sensor is corrected.

  However, the invention described in Patent Document 2 does not correct variations in output signals among a plurality of operation pads, and thus does not correct variations between channels of a plurality of elements.

  Accordingly, the present invention provides an ultrasonic probe, an ultrasonic probe adjustment method, and an ultrasonic diagnostic apparatus that reduce variations in reception gain between channels in a multi-channel transducer probe.

  In order to solve the above-described problems, in the present invention, an ultrasonic probe includes a transducer, a transmission circuit that transmits a signal that drives the transducer with ultrasonic waves, and an ultrasonic wave that is transmitted from the transmission circuit. Capacitance correction that corrects the capacitance of the line including the wiring that transmits signals from the vibrator driven by, the receiving circuit that connects to the wiring and receives the signal from the vibrator, and the wiring from the vibrator to the receiving circuit The combination with the circuit is one channel, and a plurality of channels are provided.

  In order to solve the above problems, in the present invention, in an ultrasonic probe adjustment method, a transducer, a transmission circuit that transmits a signal for driving the transducer with ultrasonic waves, and a transmission circuit that transmits the transducer. Capacitance of the line including the wiring that transmits the signal from the transducer driven by ultrasonic waves with the received signal, the receiving circuit that is connected to the wiring and receives the signal from the transducer, and the wiring from the transducer to the receiving circuit Measure the capacitance of the line including the wiring from the transducer to the receiving circuit for each channel with an ultrasonic probe equipped with multiple channels, with a combination with a capacitance correction circuit that corrects The capacity correction circuit was adjusted for each channel so that the measured capacity of each channel was the same.

  Furthermore, in order to solve the above-described problems, in the present invention, in an ultrasonic diagnostic apparatus including an ultrasonic probe and an ultrasonic apparatus main body, the ultrasonic probe includes a transducer and an ultrasonic apparatus main body. A transmission circuit for transmitting a signal for driving the vibrator transmitted from the ultrasonic wave, a wiring for transmitting a signal from the vibrator driven by the ultrasonic wave by a signal transmitted from the transmission circuit, and connecting the wiring A combination of a receiving circuit that receives a signal from the transducer and transmits the signal to the ultrasonic apparatus main body and a capacitance correction circuit that corrects the capacitance of the line including the wiring from the transducer to the receiving circuit is a single channel, and is a plurality of channels. The ultrasonic device main body includes a transmission circuit unit that transmits an ultrasonic signal applied to the transducer via a transmission circuit, and a transducer to which the ultrasonic signal transmitted from the transmission circuit unit is applied. Signal from the receiver circuit A receiving circuit unit for transmitting, a control circuit unit for controlling the transmitting circuit unit and the receiving circuit unit, a transmission / reception separating circuit unit for separating a signal transmitted from the transmitting circuit unit and a signal received by the receiving circuit unit, and a receiving circuit unit The image processing unit configured to generate an image by processing the signal received by the image processing unit, and an image display unit configured to display the image generated by the image processing unit.

  According to the present invention, a gain variation between channels of a plurality of transducers is suppressed, and an ultrasonic diagnostic image with high definition and high contrast can be obtained.

  Problems, configurations, and effects other than those described above will be clarified by the following description of embodiments.

1 is a circuit block diagram showing a schematic configuration of an ultrasound probe according to Embodiment 1 of the present invention. It is a flowchart which shows the flow of the process which adjusts the capacity | capacitance of the ultrasound probe which concerns on Example 1 of this invention. 1 is a circuit block diagram showing a schematic configuration of a capacitance measurement circuit and a capacitance correction circuit of an ultrasonic probe according to Embodiment 1 of the present invention. It is the block diagram which showed the structure of the outline of the ultrasound diagnosing device which concerns on Example 2 of this invention. It is a circuit block diagram explaining the structure of the capacity | capacitance correction circuit of the ultrasonic diagnosing device which concerns on Example 2 of this invention. It is a flowchart which shows the flow of the process which adjusts the capacity | capacitance of the ultrasonic probe which concerns on Example 2 of this invention. It is the block diagram which showed the structure of the outline of the ultrasound diagnosing device which concerns on Example 3 of this invention. It is a circuit block diagram explaining the structure of the inductor correction circuit of the ultrasonic diagnosing device which concerns on Example 3 of this invention. It is a flowchart which shows the flow of the process which adjusts the capacity | capacitance of the ultrasound probe which concerns on Example 3 of this invention. It is a figure showing the state of the wiring connecting the transducer and transmitter / receiver circuit of the ultrasonic probe, and the transducer and transmitter / receiver circuit. The length of the wiring connecting the transmitter / receiver circuit arranged near the transducer and the transducer It is a top view of the ultrasonic probe which shows the state from which the length of the wiring which connects the transmission / reception circuit arrange | positioned in the place far away is different. In the fourth embodiment of the present invention, an ultrasonic probe and an ultrasonic apparatus main body in a state where a receiving circuit, a capacitance measuring circuit, a capacitance correcting circuit, and an antiparallel diode circuit are integrated into a plurality of vibration elements into an LSI are mounted. FIG.

  The present invention relates to a vibrator, a transmission circuit for transmitting a signal for driving the vibrator with ultrasonic waves, a wiring for transmitting a signal from the vibrator driven with ultrasonic waves by a signal transmitted from the transmission circuit, and a wiring A combination of a receiving circuit that receives a signal from the vibrator connected to the oscillator and a capacity correction circuit that corrects the capacitance of the line including the wiring from the vibrator to the receiving circuit is provided as one channel, and includes a plurality of channels. Configure the ultrasonic probe, measure the capacitance of the line including the wiring from the transducer to the receiving circuit for each channel, and the capacitance correction circuit for each channel so that the measured capacitance of all channels is the same Is adjusted.

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

FIG. 1 is a diagram showing an ultrasonic probe 10 according to the first embodiment of the present invention.
11 is a multichannel vibrator, 111 is a first channel element of the multichannel vibrator 11, 11n is an nth channel element of the multichannel vibrator 11, 12 is a receiving circuit, 13 is a capacitance measuring circuit, and 14 is a capacitance. A correction circuit 16 is a circuit for passing a signal for driving the transducer 11 from a transmission circuit (not shown) of the ultrasonic apparatus body 3 and is composed of an antiparallel diode in which a pair of diodes are arranged in opposite directions. Has been. 151 is a wiring for connecting the first-channel vibrator 111 and the receiving circuit 12, and 15n is a wiring for the n-th channel.

  Each transducer 11n applies ultrasonic vibration to the subject, receives a reflected wave from the subject, and outputs a signal obtained by acoustoelectric conversion to the receiving circuit side.

  A circuit including the vibrator 11n, the receiving circuit 12, the capacity measuring circuit 13, the capacity correcting circuit 14, the antiparallel diode circuit 16, and the wiring 15n is configured for each vibrator 11n. The ultrasonic probe 10 is connected to the ultrasonic apparatus main body 3 by a cable 4.

  The ultrasonic probe 10 is formed on a glass epoxy substrate, for example, and the wiring 151 is formed by a printed copper wiring.

  The operation of the first embodiment for determining the correction capacity value of each channel will be described with reference to the flowchart of FIG.

  In the initial state, the correction capacities of all the channels are turned off, and 0 is assigned to each channel Cn to set the reference capacity value Cref = 0 (S101).

  Next, n = 1 (S102), the receiving circuit 12 measures the parasitic capacitance value of the first channel wiring 151 by the capacitance measuring circuit 13, and sets the measured capacitance value C1 in the shift register of the capacitance measuring circuit ( S103). C1 is substituted into Cref (S104).

  Next, n = n + 1 (S105), the wiring parasitic capacitance of the second channel is measured, C2 is set in the shift register of the capacitance measuring circuit (S106), and it is determined whether C2> C1 is satisfied (S107). If C2 is large (in the case of Yes), C2 is substituted into Cref (S108), and n is replaced with n + 1 (S109). On the other hand, if C2 is small in S107 (in the case of No), the process proceeds to S109 and n is replaced with n + 1. Next, it is confirmed whether n has reached the number of all vibrators (S110). If No, the process returns to S106 again to measure the wiring capacity of CHn and set it in the shift register of the capacity measuring circuit.

  The receiving circuit sequentially performs the measurement operation up to channel n (until S110 becomes Yes), and determines Cref which is the maximum value of all channels.

When the measurement and setting of the wiring capacitance is confirmed for all the vibrators in S110 (Yes in S110), n = 1 is set (S111), the channel 1 is returned to again, and from the measured C1 and Cref,
Cref−C1 = Ccal1 (Expression 2)
Thus, Ccal1 is determined and set in the capacity correction circuit 14 (S112).

Next, n is replaced with n + 1 (113), and it is confirmed whether the replaced n has reached the number of all the vibrators (S114).
Cref−Cn = Ccaln (Equation 3)
Is repeated until S114 is Yes, and Ccaln of all channels is determined and set in the capacity correction circuit 14 of each channel. In other words, the correction value Ccal n is set in the capacitance correction circuit 14 of each channel so that the wiring capacitance matches the maximum value Cref of all channels.

  As a result, the wiring capacity of the receiving unit of the probe 10 is all equal to Cref in all channels, so that there is no wiring capacity variation.

  As a result, in the signal reception from the probe 11n received by the receiving circuit 12n, the wiring capacity variation among the receiving circuits 12n is eliminated, so that the variation in reception gain between channels is also eliminated.

Next, specific examples of the capacitance measuring circuit 13 and the capacitance correcting circuit 14 will be described with reference to FIG.
In FIG. 3, 211 is a wiring capacitance current source, 212 is a capacitance measurement current source, 221 is a measurement capacitance array, 223 is a capacitance measurement register, 222 is a capacitance measurement switch, 241 is a measurement capacitance voltage, 213 is a comparator, and 214 is a flip-flop. 216 is a capacitance measurement discharge circuit, 215 is a wiring capacitance discharge circuit, 219 is a clock, 21 is a control unit, 22 is a wiring parasitic capacitance, 231 is a correction capacitance array, 233 is a capacitance correction register, 232 is a capacitance correction switch, 242 Is a wiring capacity voltage, 217 is a reception input switch, and 218 is a reception output switch.

  When bit 1 is set in the capacitance measurement register 223 and the capacitance correction register 233, corresponding portions of the capacitance measurement switch 222 and the capacitance correction switch 232 are closed, and when bit 0 is set, the capacitance measurement switch 222 and the capacitance correction switch 232 are set. The corresponding part opens.

  The clock 219 is input to the comparator 214, the wiring capacitance discharge circuit 215, and the capacitance measurement discharge circuit 216. The wiring capacitance discharge circuit 215 and the capacitance measurement discharge circuit 216 are in an open state when the clock 219 is H level, and the clock 219 is L level. In a short circuit state (that is, discharged).

  For example, the measurement capacitor array 221 and the correction capacitor array 231 are connected in parallel with single capacitors of 0.8 pF, 0.4 pF, 0.2 pF, and 0.1 pF in order from the MSB (Most Significant Bit).

  The capacitance measuring circuit 13 measures the parasitic capacitance 22 of the wiring 151 (S103 and S106 in FIG. 2), and a specific operation will be described.

  In the initial state, the capacity correction register 233 is 0000 in order from the MSB, the capacity measurement register 223 is 0010, and the clock 219 is at the H level. In this state, both the reception input switch 217 and the reception output switch 218 are in an OFF state.

  The output current of the wiring capacitance current source 211 flows to the wiring 151, charges the parasitic capacitance 22, and the wiring capacitance voltage 242 increases.

  At the same time, the output current of the capacitance measurement current source 212 flows through the capacitance measurement switch 222, charges 0.2 pF of the measurement capacitance array 221, and the measurement capacitance voltage 241 increases.

At this time, the parasitic capacitance 22 of the wiring 151 is 0.25 pF.
Since the measurement capacitance array 221 is 0.2 pF and smaller than the parasitic capacitance 22, the measurement capacitance voltage 241 is higher than the wiring capacitance voltage 242 and the output of the comparator 213 is at the H level.
When the clock 219 falls from the H level to the L level, the flip-flop circuit 214 outputs a Q output (H level) to the control circuit 21.

  At the same time, the wiring capacitance discharge circuit 215 and the capacitance measurement discharge circuit 216 are closed, so that discharge starts and the wiring capacitance voltage 242 and the measurement capacitance voltage 241 decrease to 0 volts.

  The control unit 21 determines that the wiring capacitance 22 is larger than the capacitance measurement array 222 because the Q level is H, and changes the capacitance measurement register 223 from 0010 to 0011.

  Similarly, at the next rise of the clock 219, charging of the parasitic capacitance 22 and the capacitance measuring array 222 starts, and the wiring capacitance voltage 242 and the measured capacitance voltage 241 rise.

  In this clock cycle, since the capacitance measurement array 222 is 0.3 pF with respect to the parasitic capacitance of 0.25 pF, the measurement capacitance voltage 241 is lower than the wiring capacitance voltage 242 and the output of the comparator 213 is L level.

  At the falling edge of the clock 219, the flip-flop circuit 214 outputs a Q output (L level) to the control circuit 21.

  The control unit 21 determines that the value of the capacitance measurement array 222 at this time is the wiring parasitic capacitance 22 because the Q level that has been H level has changed to L, and fixes the capacitance measurement register 223 to 0011 to End measurement.

  Because of this operation, the wiring parasitic capacitance 22 which is 0.25 pF can be measured with a measurement error of 0.3 pF and ± 0.1 pF or less.

  This measurement operation is sequentially performed up to the channel N, and the reference capacitance Cref of the wiring parasitic capacitance is determined (S107 in FIG. 2).

Next, the operation (S112 in FIG. 2) in which the capacitance correction circuit 14 determines the correction capacitance value will be described.
It is assumed that Cref = 1.0 pF, that is, the register value 1010 as a result of all channel measurements.

  The control unit 21 reads the capacity measurement register 223 of the channel 1 and obtains the register value 0011.

Binary subtraction between Cref and the capacity measurement register 223 shown in (Expression 3) is performed, and 0111 is set in the capacity correction register 233.
1010-0011 = 0111
As a result, the correction capacitor array 231 is set to 0.7 pF, and the sum of the wiring parasitic capacitance 22 and 0.25 pF is 0.95 pF, so that the error is set within ± 0.1 pF with respect to the reference capacitor 1.0 pF. The

  Thereafter, by setting the capacitance correction array 231 up to N channels, the wiring capacitance of all channels can be suppressed to ± 0.1 pF or less with respect to the reference capacitance Cref. As a result, according to the present embodiment, the wiring capacitance variation can be sufficiently reduced to such an extent that there is no problem in obtaining a high-definition and high-contrast ultrasonic diagnostic image.

  FIG. 4 is a diagram showing an ultrasonic probe 410 and an ultrasonic apparatus main body 30 of the ultrasonic diagnostic apparatus according to the second embodiment of the present invention.

  The difference from the first embodiment described with reference to FIGS. 1 and 3 is that, in the first embodiment, the control unit 21 that controls the receiving circuit 12 and the capacitance correction circuit 14 is built in the probe 10. In the present embodiment, the control unit 36 is different in that it is built in the ultrasonic apparatus main body 30. Furthermore, the present embodiment is different from the first embodiment in that the capacitance measuring circuit 13 in the first embodiment is not provided.

  The receiving circuit 12 and the capacitance correction circuit 14 are built in the ultrasonic probe 410, and the control unit 36 is arranged in the ultrasonic apparatus main body 30, and the lines from the plurality of capacitance correction circuits 14 are combined into one. A control unit 36 is connected.

  The ultrasonic apparatus main body 30 of the ultrasonic diagnostic apparatus according to the present embodiment includes a transmission signal output to the ultrasonic probe 410 side and a reception signal input from the ultrasonic probe 410 in addition to the control unit 36. A transmission / reception separation circuit 32 for separating the signal from the subject, a transmission circuit 33 for transmitting a signal for applying an ultrasonic vibration to the subject via the transmission / reception separation circuit 32 to the subject on the ultrasonic probe 410 side, A receiving circuit 34, an image processing unit 31, and an image display unit 35 that receive a reflected wave by a transducer 111 and receive a signal obtained by acoustoelectric conversion via a transmission / reception separation circuit 32 are provided.

  The image processing unit 31 controls transmission of signals from the transmission circuit 33 and reception of signals by the reception circuit 34, and processes the signals received by the reception circuit 34 to form an ultrasonic image.

  FIG. 5 shows a circuit configuration of the capacitance correction circuit 14 inside the ultrasonic probe 410 of the ultrasonic diagnostic apparatus according to the present embodiment.

  22 is a wiring parasitic capacitance, 231 is a correction capacitance array, 233 is a capacitance correction register, 232 is a capacitance correction switch, 217 is a reception input switch, and 218 is a reception output switch. These configurations are the same as those described in the first embodiment with reference to FIG.

  When bit 1 is set in the capacity correction register 233, the corresponding part of the capacity correction switch 232 is closed, and when bit 0 is set, the corresponding part of the capacity correction switch 232 is opened.

  The operation for determining the correction capacity value of each channel in the configuration of the second embodiment will be described with reference to the flowchart of FIG.

  First, in the initial state, n = 1 is set (S601), the capacity correction register 233 is set to 0000 in order from the MSB, the correction capacity of all channels is set to 0, and the reception input switch 217 and the reception output switch 218 are closed. A large value that does not actually occur is substituted for the initial level V0 and the reference reception level Vref (Gref = maximum value if reception gain) (S602).

  The control unit 36 opens the reception input switch 217 and the reception output switch 218 to drive the vibrator 111 of the first channel, and then reverses a reference transmission signal (for example, a pulse wave having an amplitude VTref) from the transmission circuit 33. The voltage is applied to the vibrator 111 via the parallel diode circuit 16 (S603).

  Subsequently, the control unit 36 closes the reception input switch 217 and the reception output switch 218, receives the signal from the reception circuit 12, which is an echo signal from the transducer 111, and inputs it to the reception circuit 34. The reception level V1 is measured (S604). The reception gain is obtained by Gn = Vn / VTref, but the following description will be made using the reception level Vn for simplification.

  Next, V1 of the reception level is compared with V0 of the initial level which is Vref (S605). If V1 is smaller than V0 (Vref) (Yes), the process proceeds to S606, and V1 is not smaller than V0 (Vref). In (No), it progresses to S607. Here, since a large value that does not actually occur is substituted for the initial level V0 that becomes Vref, V1 <V0 is obtained, and the determination result in S605 is Yes, and V1 is substituted for Vref in S606.

  Next, the value of n + 1 is replaced with n (S607), and it is determined whether the replaced new n is larger than the number of transducers (S608). As a result, when it is determined that it is still small (No in S608), a series of measurement operations from S603 are sequentially performed up to channel N, and the reference reception level Vref that is the minimum value of the reception level is determined. As an example of the minimum value of the reception level, suppose Vref = 0.50V.

  On the other hand, if it is determined in S608 that the value of n is larger than the number of transducers 11 (Yes in S608), the process proceeds to the next step of S609.

Next, the operation in which the capacitance correction circuit 14 determines the correction capacitance value will be described.
First, n is set to 1 (S609). Next, a value (for example, 0100 (capacitance value = 0.4 pF)) is set in the capacitance correction register 233 (S610).

  The control unit 36 opens the reception input switch 217 and the reception output switch 218, and applies the reference transmission signal from the transmission circuit 33 to the first vibrator 111 via the antiparallel diode circuit 16 (S611).

  Subsequently, the control unit 36 closes the reception input switch 217 and the reception output switch 218, receives the signal from the reception circuit 12, which is an echo signal from the transducer 111, and inputs it to the reception circuit 34. The reception level V1 is measured (S612).

  Next, the received level V1 obtained by measurement is compared with the previously obtained Vref (S613). If V1 is larger than Vref (Yes in S613), the process proceeds to S614 and the capacity correction register is obtained. Decrease the value by 1 bit and return to S661. On the other hand, if V1 is not larger than Vref (No in S613), the process proceeds to S615, and the magnitude of the difference between V1 and Vref is compared with the target value ΔTg between channels.

  As a result of the comparison in S615, when the difference between V1 and Vref is not less than ΔTg (in the case of No), the value of the capacity correction register 233 is increased by 1 bit (S616), and the process returns to S611. On the other hand, when the difference between V1 and Vref is equal to or less than ΔTg (in the case of Yes), the value of the capacitance correction register 233 is fixed (S617), n is updated to n + 1 (S618), and the updated n is the transducer. It is determined whether or not the number is greater than 11 (S619). If the number is greater (Yes), the capacity correction circuit 14 ends the operation of determining the correction capacity value. On the other hand, when the updated n is not larger than the number of transducers 11 (No in S619), the process returns to S610 and the steps from S610 are executed for the next transducer.

  For example, if V1 = 0.45V, the determination in S613 shows that Vref = 0.5V is smaller than that, and that the parallel capacitance added by the capacitance correction circuit 14 is 0.4 pF.

  Accordingly, the control unit 36 lowers the inductor correction register 233 by 1 bit from 0100 and changes it to 0011 (0.3 pF) (S663), returns to S611, applies the reference signal to the first vibrator 111 again, and in S612 V1 is measured again.

On the other hand, if the reception level measured in S612 is V1 = 0.52V, the corrected capacity is not lower than the reference reception level, No is determined in S613, and the process proceeds to S615 to determine a predetermined inter-channel variation target value ΔTg. (For example, 0.05 V) and Vn−Vref = 0.52−0.50 = 0.02 <0.05
Therefore, it is determined that the reference reception level is close (Yes in S615), and the inductor correction register 233 is fixed (S617).

  That is, the wiring parasitic capacitance 22 of the channel 1 is close to the reference reception level Vref when 0.3 pF is corrected.

  By sequentially correcting up to the channel N in this way, the reception level Vn (= reception gain) can be set close to the reference reception level Vref, and reception level variations between channels can be suppressed within a certain range.

  Since the correction processing of this embodiment receives an echo signal from the transducer 11n, a probe is connected to a jig imitating a human body at the time of product shipment, or a matching agent for ultrasonic diagnosis is probed at the time of customer delivery. It is effective to receive the echo signal by applying to the child.

  In the above description, the control unit 36 controls the reception input switch 217 and the reception output switch 218. However, a means for detecting the transmission level is prepared. For example, if the transmission level is 3V or more, the reception input switch 217 and the reception input are automatically performed. Even if the output switch 218 is opened, this is an embodiment of the present invention.

  FIG. 7A is a diagram showing an ultrasound probe 710 of an ultrasound diagnostic apparatus according to the third embodiment of the present invention.

  The difference from the configuration described in the first embodiment shown in FIG. 1 is that an inductor correction circuit 731n that can be set with a variable inductor value is connected between the vibrator 711 and the wiring 715n. This is based on the principle that the inductance component cancels the capacitance component. The inductor correction circuit 731 includes elements 731n that are individually connected to the elements 711n of the vibrator 711. The ultrasonic probe 710 according to the present embodiment including the inductor correction circuit 731 does not include the capacitance measurement circuit 13n and the capacitance correction circuit 14n of the ultrasonic probe 10 described in the first embodiment.

  FIG. 7B shows an inductor correction circuit 731n connected to the vibrator 711n as an example of the configuration of the inductor correction circuit 731. The inductor correction circuit 731n includes a variable inductor 732n and a multi-bit inductor correction register 733n. The inductance of the variable inductor 732n is set by the inductor correction register 733n, and is the minimum inductance when all bits are 0. This increases the inductance.

  The inductor correction register 733n is controlled by a control unit 736 disposed inside the ultrasonic apparatus main body 730. In addition to the image processing unit 731 that controls the entire ultrasonic apparatus main body 730 and performs image processing, the control unit controls the transmission / reception separation circuit 732, the transmission circuit 733, the reception circuit 734, the image display unit 735, and the inductor correction circuit 731n. 736.

Hereinafter, the inductor correction register 733n will be described as a 4-bit register.
In the third embodiment, the operation for determining the correction capacity value of each channel will be described with reference to the flowchart of FIG.

  First, n is set to 1 (S701), and in the initial state, a minimum value is set in the inductor correction register 733n. That is, 0000 is sequentially set from the inductor correction register MSB, the correction inductances of all the channels are set to the minimum value 0, the reception input switch 717 and the reception output switch 718 are closed, and the initial level V0 and the reference reception level Vref are set. Is substituted with 0V (Gref = 0 if reception gain) (S702).

  The image processing unit 737 opens the reception input switch 717 and the reception output switch 718 in order to drive the vibrator 7111 of the first channel, and then transmits a reference transmission signal from the transmission circuit 733 disposed inside the ultrasonic apparatus main body 730. (For example, a pulse wave having an amplitude VTref) is applied to the vibrator 7111 via the antiparallel diode circuit unit 716 (S703).

  Subsequently, the image processing unit 737 closes the reception input switch 717 and the reception output switch 718, receives a signal from the reception circuit 712 that is an echo signal from the transducer 7111, and measures the reception level V1 (S704). The reception gain is obtained by Gn = Vn / VTref, but the following description will be made with the reception level Vn for the sake of simplicity.

  Next, V1 of the reception level is compared with V0 of the initial level which is Vref (S705). If V1 is larger than Vref (Yes), the process proceeds to S706, and if V1 is not larger than Vref (No), S707 is reached. Proceed to Here, since the minimum value 0 has been input as the initial level V0 to be Vref, V1> V0, the determination in S705 is Yes, and V1 is substituted for Vref in S706.

  Next, the value of n + 1 is replaced with n (S707), and it is determined whether the replaced new n is larger than the number of transducers (S708). As a result, when it is determined that it is still small (in the case of No in S708), a series of measurement operations from S703 are sequentially performed up to the channel N, and the reference reception level Vref that is the maximum value of the reception level is determined. As an example of the maximum value of the reception level, it is assumed that Vref = 0.50V.

  On the other hand, when it is determined in S708 that the value of n is larger than the number of transducers 711 (Yes in S708), the process proceeds to the next step S709.

Next, the operation in which the capacitance correction circuit 14 determines the correction capacitance value will be described.
First, n is set to 1 (S709). Next, a value (for example, 0100 (numerical example, inductance value = 4 nH)) is set in the inductor correction register (S710). Next, the control unit 736. The reception input switch 717 and the reception output switch 718 are opened, and a reference transmission signal (for example, a pulse wave having an amplitude VTref) is applied from the transmission circuit 733 to the first vibrator 7111 via the antiparallel diode circuit 716 (S711).

  Subsequently, the image processing unit 731 closes the reception input switch 717 and the reception output switch 718, receives a signal from the reception circuit 712 as an echo signal by the transmission separation circuit 732, and inputs the signal to the reception circuit 734 to obtain the reception level V1. Measure (S712).

  Next, the received level V1 obtained by measurement is compared with the previously obtained Vref (S713). If V1 is smaller than Vref (Yes in S713), the process proceeds to S714 and the capacity correction register. Decrease the value by 1 bit and return to S711. On the other hand, if V1 is not smaller than Vref, the process proceeds to S715, and the magnitude of the difference between V1 and Vref is compared with the inter-channel variation target value ΔV.

  As a result of the comparison in S715, if the difference between V1 and Vref is not less than ΔV (No in the determination in S715), the value of the capacity correction register 733 is increased by 1 bit (S716), and the process returns to S711. On the other hand, when the difference between V1 and Vref is ΔV or less (Yes in S715), the value of the capacity correction register 733 is fixed (S717), n is updated to n + 1 (S718), and this update is performed. It is determined whether n is larger than the number of vibrators 11 (S719). If it is larger (Yes in S719), the inductor correction circuit 731 ends the operation of determining the correction inductance value. On the other hand, when the updated n is not larger than the number of transducers 711 (in the case of No in S719), the process returns to S710 and the steps from S710 are executed for the next transducer.

  For example, if V1 = 0.43V, the result of determination in S713 is smaller than Vref = 0.50V, and correction is insufficient for a predetermined CH variation target value ΔV (for example, 0.05V). That is, it can be seen that the series inductance 4nH added by the inductor correction circuit 731 is small.

  Therefore, the control unit 736 lowers the inductor correction register 733 by 1 bit from 0100 and changes it to 0101 (5 nH) (S714), returns to S711, applies the reference signal to the first vibrator 7111 again, and again in step S712 V1 Measure.

On the other hand, if the reception level measured in S712 is V1 = 0.52V, it is greater than Vref = 0.50V, so the determination in S713 is No, and in the determination in S715, the inter-channel variation target value ΔV (for example, , 0.05V)
Vref−Vn = 0.50−0.47 = 0.03 <0.05
Therefore, the inductor correction register 733 is fixed (S717) because it is determined that it is close to the reference reception level (Yes in S715).

  That is, when the wiring parasitic capacitance 22 of the channel 1 is corrected to 5 nH, it approaches the reference reception level.

  By sequentially correcting up to channel N in this way, the reception level (= reception gain) can be set to the highest side of all the channels, and reception level variations between channels can be suppressed within a certain range.

  In the present embodiment, the ultrasonic transducer 1010 of the ultrasonic diagnostic apparatus includes the receiving circuit 12, the capacitance measuring circuit 13, the capacitance correcting circuit 14, and the ultrasonic probe 10 illustrated in FIGS. 1 and 3 described in the first embodiment. A control unit 21 that controls the antiparallel diode circuit 16, the capacitance measuring circuit 13, and the capacitance correcting circuit 14 is attached to a plurality of vibration elements 11n in an LSI. That is, as shown in FIG. 10, the ultrasonic probe 1010 in this embodiment includes a multi-channel transducer 1011 and a plurality of transmission / reception LSIs 1020n, and wiring from a plurality of vibration elements 11n to one transmission / reception LSI 1020n. 1015n are connected, and they are configured to be controlled by the control LSI 1021. Since a plurality of transmission / reception LSIs 1020n are arranged, the lengths of the wirings 1015n connecting the transmission / reception LSIs 1020n and the multi-channel vibrator 1011 are different, which causes variations in gain between channels.

  Even in the same transmission / reception LSI 1020n, the length of each wiring 1015n may be different.

  In the present embodiment, in such a configuration, the circuit corresponding to the three control units 21 that are not incorporated in each transmission / reception LSI 1020n operates each transmission / reception LSI 1020n, and as described in the flowchart of FIG. 2 in the first embodiment. The correction capacity value of each channel is determined by a simple procedure.

  In the example described above, an example in which the correction capacitance value of each channel is determined for all the wirings 1015n of each transmission / reception LSI 1020n by the procedure described in the flowchart of FIG. However, in one transmission / reception LSI 1020n, it is considered that there is almost no difference in the length of the plurality of wirings 1015n connecting the multi-channel vibrator 1011, and the procedure of each channel is performed according to the procedure described in the flowchart of FIG. When determining the correction capacitance value, in one transmission / reception LSI 1020n, the correction capacitance value of the channel is measured as a representative of one wiring 1015n, and other wirings of the same transmission / reception LSI 1020n are corrected with the same correction value. Good.

  Further, corresponding to the second embodiment, a circuit corresponding to the control unit 21 in FIG. 3 is not built in the transmission / reception LSI 1020n, but is controlled by a control unit on the ultrasonic apparatus body 1030 side (not shown) to correct each channel. The capacitance value may be determined.

  Furthermore, the LSI may be configured by a circuit corresponding to the third embodiment, and the inductor value may be corrected instead of the parasitic capacitance.

  Thus, in the configuration in which the inside of the ultrasound probe 1010 is made into an LSI, the capacitance of each channel can be corrected to suppress the channel-to-channel gain variation of the plurality of transducers. By processing the signal from 1010 by the ultrasonic apparatus main body 1030, an ultrasonic diagnostic image with high definition and high contrast can be obtained.

  The present invention is not limited to the above-described embodiments, and includes various modifications. For example, the above-described embodiments are described in detail for the entire system in order to explain the present invention in an easy-to-understand manner, and are not necessarily limited to those having all the configurations described. Further, a part of the configuration of one embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of one embodiment. Further, it is possible to add, delete, and replace other configurations for a part of the configuration of each embodiment. Each of the above-described configurations, functions, processing units, processing means, and the like may be realized by hardware by designing a part or all of them with, for example, an integrated circuit.

  3, 30, 730, 1030 ... ultrasonic device main body 10, 710, 1010 ... ultrasonic probe 11 ... multi-channel transducer 12 ... receiving circuit 13 ... capacitance measuring circuit 14 ... Capacitance correction circuit 15n ... n-th channel wiring

Claims (20)

A vibrator,
A transmission circuit for transmitting a signal for driving the vibrator with ultrasonic waves;
Wiring for transmitting a signal from the transducer driven by ultrasonic waves by a signal transmitted from the transmission circuit;
A receiving circuit connected to the wiring and receiving a signal from the vibrator;
The combination with a capacitance correction circuit that corrects the capacitance of the line including the wiring from the vibrator to the receiving circuit is one channel,
An ultrasonic probe characterized by having multiple channels.   2. The ultrasonic probe according to claim 1, wherein the capacitance correction circuit includes a capacitance correction register, a correction capacitance array, and a capacitance correction switch. Child.   2. The ultrasonic probe according to claim 1, further comprising a switch between the receiving circuit and the transducer, wherein the capacitance correction circuit is connected between the switch and the transducer. Ultrasonic probe characterized by   2. The ultrasonic probe according to claim 1, further comprising a capacitance measuring circuit that measures a capacitance of a line including the wiring from the transducer to the receiving circuit.   The ultrasonic probe according to claim 1, wherein the capacitance correction circuit is configured by an inductor circuit having a variable inductor value, and the inductor circuit is connected between the vibrator and the wiring. An ultrasonic probe characterized by that.   2. The ultrasonic probe according to claim 1, wherein the transmission circuit, the reception circuit, and the capacitance correction circuit for a plurality of channels are integrated.   The ultrasonic probe according to claim 6, wherein the transmission circuit, the reception circuit, and the capacitance correction circuit for the plurality of channels are integrated into an LSI and are integrated into one LSI. An ultrasonic probe characterized by having a correction amount of wiring connected to a terminal as a correction amount of wiring connected to the remaining receiving terminals of the LSI. A transducer, a transmission circuit for transmitting a signal for driving the transducer with ultrasonic waves, a wiring for transmitting a signal from the transducer driven by ultrasonic waves by a signal transmitted from the transmission circuit, and the wiring A combination of a receiving circuit that receives a signal from the transducer connected to the transducer and a capacitance correction circuit that corrects the capacitance of the line including the wiring from the transducer to the receiving circuit, for one channel. A method of adjusting an ultrasonic probe with minutes,
Measure the capacitance of the line including the wiring from the vibrator to the receiving circuit for each channel,
The method of adjusting an ultrasonic probe, wherein the capacitance correction circuit is adjusted for each channel so that the measured capacitances of all channels are the same.   9. The method of adjusting an ultrasonic probe according to claim 8, wherein adjusting the capacity correction circuit for each channel specifies a channel having the largest capacity among the measured capacity for each channel. And adjusting the capacity correction circuit of another channel so that the capacity of the channel having the specified maximum capacity is the same as the capacity of the channel having the specified maximum capacity.   9. The method of adjusting an ultrasonic probe according to claim 8, wherein the adjustment of the capacitance correction circuit is adjusted using a capacitance correction register, a correction capacitance array, and a capacitance correction switch. To adjust the ultrasonic probe.   9. The method of adjusting an ultrasonic probe according to claim 8, wherein the switch is connected between the switch and the transducer in a state where the switch between the receiving circuit and the transducer is turned off. An ultrasonic probe adjustment method comprising adjusting the capacitance correction circuit.   9. The method of adjusting an ultrasonic probe according to claim 8, wherein the capacitance correction circuit is configured by an inductor circuit having a variable inductor value connected between the vibrator and the wiring, and the capacitance The method of adjusting an ultrasonic probe, wherein the correction circuit is adjusted by adjusting an inductor value of the inductor circuit.   9. The method of adjusting an ultrasonic probe according to claim 8, wherein the transmission circuit, the reception circuit, and the capacitance correction circuit for the plurality of channels are integrated into an LSI and are integrated into an LSI. A method of adjusting an ultrasonic probe, characterized in that a correction amount of a wiring connected to one receiving terminal is taken as a correction amount of a wiring connected to the remaining receiving terminals of the LSI. An ultrasonic diagnostic apparatus including an ultrasonic probe and an ultrasonic apparatus main body,
The ultrasonic probe is
A vibrator,
A transmission circuit for transmitting a signal for driving the vibrator with ultrasonic waves transmitted from the ultrasonic device main body;
Wiring for transmitting a signal from the transducer driven by ultrasonic waves by a signal transmitted from the transmission circuit;
A receiving circuit connected to the wiring and receiving a signal from the transducer and transmitting the signal to the ultrasonic device body;
The combination with a capacitance correction circuit that corrects the capacitance of the line including the wiring from the transducer to the receiving circuit is one channel, and includes a plurality of channels.
A transmission circuit unit for transmitting an ultrasonic signal applied to the vibrator via the transmission circuit;
A receiving circuit unit that receives a signal from the transducer to which the ultrasonic signal transmitted from the transmitting circuit unit is applied, via the receiving circuit;
A control circuit unit for controlling the transmission circuit unit and the reception circuit unit;
A transmission / reception separation circuit unit for separating a signal transmitted from the transmission circuit unit and a signal received by the reception circuit unit;
An image processing unit that generates an image by processing a signal received by the receiving circuit unit;
An ultrasonic diagnostic apparatus comprising: an image display unit that displays an image generated by the image processing unit.   15. The ultrasonic diagnostic apparatus according to claim 14, wherein the control unit is configured so that the capacitance of the line including the wiring from the transducer to the receiving circuit of the plurality of channels becomes equal within a predetermined error range. An ultrasonic diagnostic apparatus that controls the capacitance correction circuit.   15. The ultrasonic diagnostic apparatus according to claim 14, wherein the control unit includes a channel having a maximum capacity of a line including the wiring from the transducer of the plurality of channels to the receiving circuit. An ultrasonic diagnostic apparatus, wherein the capacity correction circuit of the other channel is controlled to match the capacity.   15. The ultrasonic diagnostic apparatus according to claim 14, wherein the capacitance correction circuit of the ultrasonic probe includes a capacitance correction register, a correction capacitance array, and a capacitance correction switch. Ultrasonic diagnostic equipment.   15. The ultrasonic diagnostic apparatus according to claim 14, further comprising a switch between the receiving circuit of the ultrasonic probe and the transducer, wherein the capacitance correction circuit is between the switch and the transducer. An ultrasonic diagnostic apparatus connected to   15. The ultrasonic diagnostic apparatus according to claim 14, wherein the capacitance correction circuit of the ultrasonic probe is configured by an inductor circuit having a variable inductor value, and the inductor circuit includes the transducer and the wiring. An ultrasonic diagnostic apparatus characterized by being connected in between.   15. The ultrasonic diagnostic apparatus according to claim 14, wherein the transmission circuit, the reception circuit, and the capacitance correction circuit for a plurality of channels of the ultrasonic probe are integrated into an integrated circuit. Ultrasonic diagnostic equipment.

Images