Invention content
The main object of the present invention is provides a kind of ultrasonic transmitter-receiver probe, it is intended to solve the ultrasound in existing fetus-voice meterThe technical issues of wave transceiver probe cannot precisely detect heart of fetus.
The present invention proposes a kind of ultrasonic transmitter-receiver probe, conductive including substrate, extraction electrode, the first conductive layer and secondLayer；
First conductive layer is attached on the first surface of the substrate, on the second surface opposite with the first surfaceAttach second conductive layer；
Second conductive layer includes multiple conductive subregions, is distributed to multiple conductive subregion mutually insulateds；
The extraction electrode includes the first extraction electrode and the second extraction electrode；First extraction electrode and described firstConductive layer is electrically connected；Second extraction electrode include it is multiple, multiple second extraction electrodes respectively with multiple conductionsSubregion.
Preferably, first conductive layer and the second conductive layer on the substrate surface by coating piezoelectric material shapeInto the piezoelectric material includes one kind in piezopolymer, piezoelectric ceramics and piezo-electric crystal.
Preferably, the piezopolymer includes Kynoar, Kynoar-trifluoro ethylene copolymer and includesIt is one or two kinds of in the Kynoar of air.
The present invention also provides a kind of ultrasonic wave transducer array apparatus, including：Above-mentioned ultrasonic transmitter-receiver probe, is also wrappedInclude ultrasonic driving apparatus, driving circuit；
Described driving circuit one end connects the ultrasonic driving apparatus, and the other end connects the ultrasonic transmitter-receiver probeEach conductive subregion, each conductive subregion receives drive signal that the ultrasonic driving apparatus is sent simultaneously respectivelyGenerate ultrasonic signal.
Preferably, the ultrasonic wave transducer array apparatus, including multiple first antiparallel diodes pair, multiple described firstAntiparallel diode to being connected in series between each conductive subregion and the ultrasonic driving apparatus respectively；Ultrasonic wave drivesThe drive signal that dynamic device generates under driving voltage effect, is acted on simultaneously by multiple first antiparallel diodes pairEach conductive subregion, to generate ultrasonic signal and launch, and the ultrasonic wave that each conductive subregion receivesFeedback signal is respectively by connected first antiparallel diode to preventing back to the ultrasonic driving apparatus.
Preferably, the ultrasonic wave transducer array apparatus further includes ultrasound feedback signal calculation circuit, the ultrasonic waveFeedback signal counting circuit is connected between each conductive subregion and each first antiparallel diode pair, receives each instituteIt states the ultrasound feedback signal that conductive subregion receives and calculates size.
Preferably, the ultrasound feedback signal calculation circuit includes a plurality of signal processing branch, the processing branch per barsRoad exports the ultrasound feedback signal that each conductive subregion receives respectively, and big according to the intensity of ultrasound feedback signalThe orientation of the most strong ultrasound feedback signal of small discernible signal intensity.
Preferably, the signal processing branch includes the resistor and signal amplifier of series connection；Each resistor in seriesBetween each signal amplifier and each conductive subregion.
Preferably, the ultrasonic wave transducer array apparatus, further includes multiple second antiparallel diodes pair, and each described secondAntiparallel diode is connected to one end between the resistor and signal amplifier, other end ground connection.
The present invention also provides a kind of fetus-voice meter, including above-mentioned ultrasonic wave transducer array apparatus.
Preferably, the fetus-voice meter further includes shell, and the ultrasonic transmitter-receiver probe is with the conduction of the first surfaceLayer is close to the outer casing inner wall, and the ultrasonic transmitter-receiver probe is in planar or arc curved shape.
Preferably, the thickness of the shell is 1/4 wavelength of sheathing material sound wave；The acoustic impedance of the sheathing material is inUltrasonic transmitter-receiver is popped one's head between material impedance and propagation medium impedance.
Preferably, N times of half-wavelength for sheathing material sound wave of the thickness of the shell, N=0,1,2,3 or 4；It is described outerThe acoustic impedance of shell material is between ultrasonic transmitter-receiver probe material impedance and propagation medium impedance.
Advantageous effects of the present invention：The present invention passes through second surface that the ultrasonic transmitter-receiver of large area is popped one's head inConductive layer be designed to the conductive subregions of the multiple array distributions separated, ultrasonic driving apparatus is in the driving of driving voltageIt is lower to drive multiple conductive subregions, it can be achieved that synchronizing, realize the big cross section ultrasonic wave of large area ultrasonic transmitter-receiver probe transmittingBeam realizes precise positioning to increase overlay area；And when receiving ultrasound feedback signal, multiple conduction subregion individual receptionsFeedback signal, solves the different receiving areas of integrated large area ultrasonic transmitter-receiver probe, and the feedback signal of reception is mutualThe technical issues of interference, improves accuracy of detection.
Specific embodiment
It should be appreciated that the specific embodiments described herein are merely illustrative of the present invention, it is not intended to limit the present invention.
With reference to Fig. 1, the ultrasonic transmitter-receiver of one embodiment of the invention is popped one's head in, including substrate 1, extraction electrode, the first conductionLayer and the second conductive layer；
First conductive layer, the second surface opposite with the first surface are attached on the first surface of the substrate 1It is upper to attach second conductive layer；
Second conductive layer includes multiple conductive subregions 2, is distributed to 2 mutually insulated of multiple conductive subregions；
The extraction electrode includes the first extraction electrode and the second extraction electrode；First extraction electrode and described firstConductive layer is electrically connected；Second extraction electrode include it is multiple, multiple second extraction electrodes respectively with multiple conductionsSubregion 2 is electrically connected.
As shown in Fig. 2, the embodiment of the present invention passes through second surface that the ultrasonic transmitter-receiver of large area is popped one's head inConductive layer is isolated into multiple conductive subregions 2, the conductive subregion 2 of multiple array arrangements is integrated on a substrate 1, with oneThe conductive layer of the first surface of body forms the sensor of multiple array distributions, and ultrasonic driving apparatus is in the driving of driving voltageIt is lower to drive multiple conductive subregions 2, it can be achieved that synchronizing, realize the big cross section ultrasonic wave of large area ultrasonic transmitter-receiver probe transmittingBeam realizes precise positioning to increase overlay area；And when receiving ultrasound feedback signal, multiple conduction subregions 2 independently connectFeedback signal is received, the different receiving areas for solving large area ultrasonic transmitter-receiver probe, the feedback signal of reception interferesThe technical issues of, improve accuracy of detection.Citing ground, the ultrasonic transmitter-receiver probe of the present embodiment is collects on one big area glass substrateInto 9 or 12 grid-like continuous arrangements and mutually independent conductive subregion 2.Conductive son in other embodiments of the inventionArrangement mode, shape, pattern and the quantity in region 2 can be designed according to actual needs.
Further, the first conductive layer of the ultrasonic transmitter-receiver probe of the present embodiment and the second conductive layer pass through describedIt coats piezoelectric material on substrate 1 to be formed, the piezoelectric material includes one in piezopolymer, piezoelectric ceramics and piezo-electric crystalKind.
Piezopolymer is at low cost compared to piezoelectric ceramics or piezo-electric crystal, therefore the preferred piezo-polymeric of the present embodimentObject is as ultrasonic transmitter-receiver the first conductive layer of probe and the coating material of the second conductive layer, to reduce large area ultrasonic transmission/receptionThe cost of manufacture of device probe.The preferred Kynoar, Kynoar-trifluoro ethylene copolymer of the present embodiment and include skyIt is one or two kinds of in the Kynoar of gas.
With reference to Fig. 3, the present invention also provides a kind of ultrasonic wave transducer array apparatus, including：Above-mentioned ultrasonic transmitter-receiverProbe, further includes ultrasonic driving apparatus 3, driving circuit；
Described driving circuit one end connects the ultrasonic driving apparatus 3, and the other end connects the ultrasonic transmitter-receiver and visitsEach conductive subregion 2 of head, each conductive subregion 2 receive the driving that the ultrasonic driving apparatus 3 is sent respectivelySignal simultaneously generates ultrasonic signal.
The ultrasonic wave transducer array apparatus of the present embodiment, when emitting drive signal, ultrasonic driving apparatus 3 passes through drivingCircuit drives each conductive subregion 2 that ultrasonic transmitter-receiver is popped one's head in simultaneously, and ultrasonic transmitter-receiver probe is as an entiretyTransmitting ultrasonic signal outward is accumulated, increase ultrasound with the effective cross section for increasing ultrasonic transmitter-receiver probe transmitting ultrasonic beamThe overlay area of wave signal, to solve the problems, such as to be not easy to position.
Further, the ultrasonic wave transducer array apparatus, it is multiple described including multiple first antiparallel diodes to 4First antiparallel diode is connected in series in 4 respectively between each conductive subregion 2 and the ultrasonic driving apparatus 3；The drive signal that ultrasonic driving apparatus 3 generates under driving voltage effect, by multiple first antiparallel diodes to 4Each conductive subregion 2 is acted on simultaneously to generate ultrasonic signal, and is launched by ultrasonic transmitter-receiver probe, andThe ultrasound feedback signal that each conductive subregion 2 receives is hindered by connected first antiparallel diode 4 respectivelyOnly return to the ultrasonic driving apparatus 3.
The ultrasonic wave transducer array apparatus of the present embodiment, when receiving feedback signal, by the first antiparallel diode to 4The switching circuit of composition makes each conductive subregion 2, and into feedback signal reception area is independent, the first of the present embodiment is anti-flatRow diode pair 4 includes two antiparallel connected diodes, as shown in fig. 6, crest voltage is 0.7V, with conventional diodeStructure it is different.Each conduction subregion 2 passes through the first antiparallel two pole respectively by ultrasonic driving apparatus in the present embodimentPipe drives simultaneously to 4, as shown in figure 3, with the connection relation example of limited quantity, each conductive subregion of the present embodiment in figure2 are all connected with the first antiparallel diode to 4, and the ultrasonic transmitter-receiver probe or planar ultrasonic wave transceiver probe being bentFirst antiparallel diode of connection is to 4 also without any difference.The drive voltage range of the present embodiment ultrasonic transmitter-receiver probeFor 10-100V, driving frequency MHZ, ultrasonic driving apparatus impedance is low.Within the driving pulse period, when driving voltage is zeroWhen, electric current zero, the first antiparallel diode has very high impedance to 4, and each conductive subregion 2 is caused to be driven with ultrasonic waveDynamic device disconnects, and when receiving feedback signal, the feedback signal that each conduction subregion 2 receives must drive with ultrasonic waveDevice disconnection, because its Low ESR absorbs or weaken the feedback signal received, and each conductive reception of subregion 2 is anti-The feedback signal that feedback signal must be received with other conductive subregions 2 be isolated from each other disconnection, just can effectively detect feedback letterNumber, the present embodiment is by the first antiparallel diode to 4 and the matched mode of ultrasonic transmitter-receiver probe of special structure designOptimization solves above-mentioned technical proposal.As shown in fig. 6, the voltage-current characteristic of single diode is：When forward voltage is (from arrow tailTo head) apply forward voltage, during more than 0.7V, current direction arrow direction, but the positive direction electric current less than 0.7V will not produceRaw electric current.But when voltage is applied to negative direction (from arrow to tail direction), no current flows.First antiparallel diode pair4 be two diodes in parallel and Opposite direction connection, and the ultrasonic beam for having reached emission mode simultaneously according to voltage-current characteristic hasBig cross-sectional area, under reception pattern, the feedback signal that each conduction subregion 2 receives is not interfere with each other, and do not driven by ultrasonic waveThe voltage pulse interference of device improves the reliability of detection signal.
The substrate 1 of the ultrasonic transmitter-receiver probe of the present embodiment is PVDF, as shown in Figure 3 on the first surface of PVDFEven ground coated conductive layer, and the electrode of conductive layer is ground connection；Conductive layer on second surface is divided into many regions, each areaIt is separated between domain with dotted line, and independent control, as shown in Figure 4.When ultrasonic transmitter-receiver probe as transmission mode in use, allConductive subregion 2 be driven via storage capacitors simultaneously, the large area conductive region single as one is activated, the wheel of the ultrasonic beam of transmittingExterior feature has big cross-sectional area, when ultrasonic transmitter-receiver probe bending is in use, the ultrasonic beam of bigger cross-sectional area can be propagated.When ultrasonic transmitter-receiver probe as reception mode in use, conductive region is isolated into multiple conductive subregions 2, each conductionSubregion 2 is respectively received ultrasound feedback signal, and selects maximum feedback signal as detection signal, to improve detection essenceAccuracy.In the transmission mode, ultrasonic signal directly enters heart of fetus from ultrasonic transmitter-receiver detecting head surface.Due to the fetus heartThe dirty much smaller size than ultrasonic transmitter-receiver probe, the ultrasonic signal of reflection spread or scatter in heart, and scattering surpassesSound wave is modeled as the point source of radiation.As shown in figure 5, the transmission route A of conductive subregion 2 vertically reached from cardiac positionDistance is shortest, and is more than A routes with transmission range of the conductive subregion 2 there are the B routes of plane holder degree.Apart from shortestThe feedback signal of transmission route is most strong, and the phase of reception signal also influences feedback signal in same conductive subregion 2Power, as shown in figure 4, the feedback signal that the corresponding conductive subregion 2 of hatched area receives is most strong.
Influence of the phase effect to feedback signal, as shown in figure 5, the ultrasound in section of popping one's head in from heart to ultrasonic transmitter-receiverWave is almost 90 degree along the angle of direct route A and ultrasonic transmitter-receiver detecting head surface, and reaching ultrasonic transmitter-receiver from heart visitsThe distance of head is most short.Fig. 5 medium wavelength λ regions are the phase face of spherical surface ultrasonic wave, block curve and dashed curve expression sound respectivelyPress the positive negative of wave.It is that 2 all the points of conduction subregion receive in the feedback signal that same conductive subregion 2 receivesAcoustic pressure summation.The high phase place of sound pressure phase is almost constant in region, but low phase changes with the variation of positive charge, andAnd variation is very big.In low phase, positive and negative acoustic pressure is cancelled out each other, and becomes very weak, so the signal from low phase is than comingIt is weak much from the signal of high phase place.As described above, the intensity of feedback signal that each conduction subregion 2 receives is different, such as oneThe feedback signal that a conduction subregion 2 receives is most strong, and the feedback signal that other conductive subregions 2 receive is weaker, when allWhen conductive subregion 2 is electrically connected, the most strong feedback signal of intensity is to the weaker conductive subregion 2 of other feedback signalsDiffusive transport causes all feedback signals to die down.
Further, the ultrasonic wave transducer array apparatus further includes ultrasound feedback signal calculation circuit 5, described superSound wave feedback signal counting circuit 5 is connected to each conductive subregion 2 and each first antiparallel diode between 4,It receives the ultrasound feedback signal that each conductive subregion 2 receives and calculates size.
For the present embodiment when receiving feedback signal, the feedback signal that each conduction subregion 2 receives is anti-by ultrasonic waveFeedback signal counting circuit 5 exports outward.Further, the ultrasound feedback signal calculation circuit 5 includes a plurality of signal processingBranch, per bars, processing branch exports the ultrasound feedback signal that each conductive subregion 2 receives respectively, and according to superThe orientation of the most strong ultrasound feedback signal of the intensity size discrimination signal strength of sound wave feedback signal.
Further, the signal processing branch includes the resistor 50 of series connection and signal amplifier 51；Each resistanceDevice 50 is series between each signal amplifier 51 and each conductive subregion 2.The resistors such as R1, R2 50 are fed back to accordinglySignal amplifier 51, the resistance value very little of resistor 50, feedback signal can pass through, outside will pass through signal amplifier 51It exports and shows corresponding testing result.
Further, the ultrasonic wave transducer array apparatus further includes multiple second antiparallel diodes to 52, each describedSecond antiparallel diode is connected to 52 one end between the resistor 50 and signal amplifier 51, other end ground connection.
Second antiparallel diode of the present embodiment is to inhibit the high-voltage pulse of below 0.7V to 52 effect, to avoid superThe function of the driving pulse damage high-gain amplifier of sound wave driving device.Second antiparallel diode of the present embodiment to 52,With very high impedance and signal is received less than ± 0.7V, so the second antiparallel diode does not influence signal amplifier 51 to 52Receive feedback signal.The output signal of the signal amplifier 51 of the present embodiment passes through doppler Method or pulse timing method and otherSpecific algorithm carries out integrated treatment, is moved with the rate for detecting heart, and determines that fetal rhythm is normal or abnormal situation.
The present invention also provides a kind of fetus-voice meter, including above-mentioned ultrasonic wave transducer array apparatus.Further, the fetal rhythmInstrument further includes shell, and the ultrasonic transmitter-receiver is popped one's head in the conductive layer of the first surface close to the outer casing inner wall, describedUltrasonic transmitter-receiver probe is in planar or arc curved shape.
The assembling shape of the ultrasonic transmitter-receiver probe of the present embodiment can be planar or arc curved shape, but be intended to meetHeart is popped one's head in ultrasonic transmitter-receiver in the range of the distance of near field for emitting ultrasonic beam.The fetus-voice meter of the present embodiment has shell,Shell is the external structure of ultrasonic transmitter-receiver probe, to prevent the external disturbance from machinery, chemistry or electromagnetism source, but shellThickness and material can influence ultrasonic transmitter-receiver probe performance.From the point of view of acoustical behavior, the design and material of outer casing thicknessThe specific score of medium wavelength is related.According to the relationship with wavelength, bandwidth may be modified as wider or narrower.When pulse timing is surveyedWhen amount is for detecting heart of fetus movement, need, using poop, to need wide bandwidth.When using Doppler frequency shift, due toHigh sensitivity needs to use long pulse (pulse) and narrow bandwidth.Fetus-voice meter non-housing in other embodiments of the invention, ultrasonic wave are receivedDevice probe is sent out directly as detection contact surface.
As shown in fig. 7, the ultrasonic beam of ultrasonic transmitter-receiver probe transmitting is directly propagated from ultrasonic transmitter-receiver probe,But in a critical point X=X of near-field region CN, ultrasonic beam starts to spread, in the D of far-field region, in disperse state.Expand hereinArea is dissipated, sound pressure level (SPL) is maximum in reference axis, weaker with the distribution function of reference axis vertical direction.The distribution of SPL is by frequencyRate, frequency converter size and spread speed determine, are provided by the simple equation of far-field distribution.Angle θ1/2Place's acoustic pressure becomes 50%,θ1/2=arcs i n (1.1 λ/π a) 0.35 λ of ≌/a, (λ is wavelength, and 2a is the diameter of ultrasonic transmitter-receiver probe), for example, directly2a=12 millimeters of diameter, λ=1.5 millimeter (1MHz), θ1/2=5.0 degree, or λ=0.75 millimeter (2MHz), θ1/2=2.5 degree(2MHz).Even if but the ultrasonic transmitter-receiver of small area probe ultrasonic beam spread, the cross section of ultrasonic beam it is straightDiameter is also not big enough, is difficult to find cardiac position by mobile ultrasonic transmitter-receiver probe.But the ultrasonic beam in near-field region CIt will not spread, the profile or size of ultrasonic beam are roughly the same or smaller with the size that ultrasonic transmitter-receiver is popped one's head in, andCritical point X=XNPlace is minimum, and distance is more than X=XNStart to dissipate later, the distribution of the ultrasonic beam in near-field region C is shownComplicated pattern is shown, it is impossible to be represented with simple equation, referred to as near field distribution.Fig. 8 is round ultrasonic transmitter-receiver probeThe distributed wave of ultrasonic beam, for zero at the center in area near field, zero is popped one's head in not close in ultrasonic transmitter-receiver, bestDesign XNMore than the distance of ultrasonic transmitter-receiver probe to heart, as shown in the figure, working as X=XNThe size ratio X of ultrasonic beam when/3=XNThe size of ultrasonic beam when/2 is big, X=XNWhen minimum, and X ＞ XNWhen, ultrasonic beam starts to spread.
The round ultrasonic transmitter-receiver probe (2a=12mm) of small size, near-field region is to passing through X between far-field regionN=a2/ λ carries out transition, for example, diameter 24mm (1MHZ) and diameter 48mm (2MHZ).In far-field region, ultrasonic beam is according to far fieldEquation is diffused, in critical point X=XNWhen ultrasonic dimensional it is minimum, about ultrasonic transmitter-receiver probe cross-sectional area40%, referred to as beam waist or focus.By taking the ultrasonic beam diffusion of diameter 12mm as an example, ultrasonic transmitter-receiver probe 5 degree (1MHZ)Or 2.5 degree (2MHZ), 50% in the diameter of ultrasonic beam at ultrasonic transmitter-receiver probe 10cm is converted to 17.6mm(1.0MHZ) and 8.8mm (2.0MHZ).
When in another embodiment of the present invention using PZT (1 or 2MHZ, PZT refer to lead titanate piezoelectric ceramics) of diameter 12mm,Ultrasonic beam will not seriously be spread in far-field region.Average distance of the heart of fetus apart from skin is 90mm.Far field ultrasoundWave beam has small cross-sectional area, it is difficult to position heart by observing feedback signal.When PZT diameter dimensions become larger, XNBecomeBigger (XNWith a2It is directly proportional), much larger than the distance of skin to heart of fetus.X in order to obtainN=400mm, ultrasonic transmitter-receiver are visitedHead diameter is necessary for 49mm (1MHZ) or 35mm (2MHZ), and such heart is located at near-field region, the ultrasonic beam at cardiac positionDiameter dimension for 49mm or 35mm, it is single nor too small although size is not big enough.Therefore, ultrasonic transmitter-receiver probe is straightDiameter 2a=50mm is minimum dimension, when ultrasonic transmitter-receiver probe diameter size is less than 50mm, such as 2a=30mm so that heartDistance is than XNIt is slightly shorter, and the size of ultrasonic beam can not position cardiac position much smaller than 30mm.To more easily position the heartDirty position needs the ultrasonic beam of big cross-sectional area, so the diameter dimension of ultrasonic transmitter-receiver probe must be as big as possible.ThanSuch as, ultrasonic transmitter-receiver probe diameter 2a=90mm, frequency 2MHZ, XNFor 2.7m, cardiac position compares XNIt is short, ultrasonic beamCross-sectional area easily puts position cardiac position close to the diameter 90mm of Chang'an device.But PZT material is of high cost, the present embodimentIt is preferred that ultrasonic transmitter-receiver probe prepared by piezopolymer.
In one embodiment of the invention, the thickness of the shell is 1/4 wavelength of sheathing material sound wave；The sheathing materialAcoustic impedance is between ultrasonic transmitter-receiver probe material impedance and propagation medium impedance.It is provided to design wider bandwidthSubstantially pulse excitation and reception.
In another embodiment of the present invention, gradually increase and gradually decay to be more advantageous to the long pulse of high RST amplitude,The sharp resonant ultrasonic transceiver probe of narrow bandwidth is devised, the thickness of the shell is the half-wavelength of sheathing material sound waveN times, N=0,1,2,3 or 4；The acoustic impedance of the sheathing material, which is in ultrasonic transmitter-receiver probe material impedance and propagates, to be situated betweenBetween matter impedance.
The ultrasonic transmitter-receiver frequency probe ranging from 1MHZ to 2MHZ of the present embodiment, to avoid negative shadow is caused to fetusIt rings.The PVDF of individual layer and the resonant frequency of conductive layer are too high, are not suitable for fetus-voice meter, and the present embodiment is by designing the PVDF of multilayerUltrasonic transmitter-receiver is popped one's head in, and resonant frequency is made to be reduced to 2MHZ, as shown in Figure 10, gold is added in the both side surface of polymeric layerBelong to layer, and be added to preceding matching layer to generate bandwidth.Concrete structure is as follows：The both side surface of 52 μm of PVDF60, it is symmetrical to coat12 μm of silver inks 61 symmetrically coat 5 μm of epoxy 62, both sides epoxy 62 in 61 layers of both sides silver inks after drySurface 200 μm of copper 63 is respectively coated, the finally plastics 64 of 300 μm of coating and mixing in the layers of copper 63 close to heart sideGrease 65.
In other embodiments of the invention, when PVDF is interior hollow structure (or interior fill air), and thickness reaches 500 μm,The metal layer of front and rear layer, such as above-mentioned layers of copper can be removed, and when resonant frequency is 1MHZ, matching layer before also can remove, becauseIt is acoustic impedance close to human body, and sensitizing pulse is sharp enough, retention substrate PVDF60, silver inks conductive layer 61 and protectsApplication can be met by protecting and leading the layer polymerization object protective layer 66 of 25-50 μm of electric layer, as shown in figure 11.
The embodiment of the present invention is designed by the conductive layer of second surface that the ultrasonic transmitter-receiver of a large area is popped one's head inInto the conductive subregion 2 of the multiple array distributions separated, ultrasonic driving apparatus is under the driving of driving voltage, it can be achieved that sameThe multiple conductive subregions 2 of step driving realize that large area ultrasonic transmitter-receiver probe emits big cross section ultrasonic beam and covered to increaseCover area realizes precise positioning；And when receiving ultrasound feedback signal, multiple conduction 2 individual reception feedback signals of subregion,It the technical issues of different receiving areas of solution large area ultrasonic transmitter-receiver probe, the feedback signal of reception interferes, carriesHigh measurement accuracy.
The foregoing is merely the preferred embodiment of the present invention, are not intended to limit the scope of the invention, every utilizationThe equivalent structure or equivalent flow shift that description of the invention and accompanying drawing content are made directly or indirectly is used in other correlationsTechnical field, be included within the scope of the present invention.