464 results about "Piezoelectric transduction" patented technology

The technology described herein is directed towards resonators that incorporate or are closely coupled to transducers from which energy is harvested. The resonators can be unit cells of a metasurface configured for narrowband sound absorption by phase cancellation of the acoustic wave Electroacoustic transducers such as piezoelectric transducers can be positioned, e.g., at the neck ports of the resonators, to generate electricity as the air pressure of incoming acoustic waves enters the unit cells. Energy can be harvested from the electricity, and stored for usage and / or used directly to power a device. Such a device powered by the harvested energy can change the resonant frequency of the device, e.g., by changing temperatures in the resonators' air cavities, changing respective dimensions of the respective air cavities, or changing the resonant frequency of the unit cells resonators by changing respective airflow in the respective air cavities.

The invention discloses a method, a system, equipment and a medium based on a multi-composite ultrasonic penetration technology, and the method comprises the steps: generating high-frequency fundamental ultrasonic waves through a piezoelectric transducer array, and adjusting the frequency range to match the acoustic impedance characteristic of target soil; first, second and third harmonics are generated through the induction of a nonlinear medium in the fundamental wave propagation process, the phases of the harmonics are adjusted to realize coherent superposition, and the fundamental wave and the first, second and third harmonics are guided into a composite waveguide device for focusing and delay compensation to form a high-energy composite wave beam; a pulse interval is adjusted by adopting an intermittent emission strategy so as to inhibit energy attenuation in the soil; reflected wave spectrum components are monitored through an embedded acoustic sensor array, and driving parameters are dynamically adjusted; and residual ultrasonic energy is captured and fed back to a driving circuit to form a closed-loop energy utilization system. By integrating multi-order harmonic resonance and a dynamic frequency tuning technology, efficient transmission and deep penetration of ultrasonic energy in a complex medium are realized.

The invention relates to a multi-modal fusion pipeline damage positioning method, which comprises the following steps of: uniformly arranging piezoelectric transducer arrays along the circumferential direction of a pipeline, generating non-frequency dispersion L (0, 2) and T (0, 1) guided waves respectively excited by 70kHz sine pulses as excitation signals, and unidirectionally spreading the excitation signals along the pipeline; the method comprises the following steps: acquiring reflection echoes at a to-be-measured section of a pipeline, and performing matched filtering, omega-k domain filtering and circumferential modal decomposition on the reflection echoes to obtain two modal components in an L (0, 2) mode and a T (0, 1) mode; performing back propagation and focusing imaging on each modal component to obtain imaging results under two modals L (0, 2) and T (0, 1); and fusing the imaging results in the two modals to obtain a multi-modal fusion pipeline damage image. Compared with the prior art, the method has the advantages that the problem that sensitivity of different defect types is difficult to consider due to single-mode optimization and the problems of signal waveform distortion and energy dispersion existing in multi-mode signals are solved.

Disclosed herein are ultrasound transducers that are selectively insulated to thereby enable the transducers to be exposed to an electrically conductive fluid without causing a short circuit between electrodes of the transducers. Such a transducer includes a piezoelectric transducer body having a first surface and a second surface that are spaced apart from one another and do not intersect with one another. The ultrasound transducer also includes a first electrode disposed on the first surface, a second electrode disposed on the second surface, and an electrical insulator covering only one of first and second electrodes and configured to inhibit electrical conduction between the first electrode and the second electrode when the ultrasound transducer is placed within an electrically conductive fluid. Also disclosed are apparatuses and systems that include such a transducer. Related methods are also disclosed herein.

The invention discloses an ultrasonic phased array driven graphene oxide flow stripping and closed-loop regulation and control system and method, and the system comprises an ultrasonic phased array module, and a piezoelectric transducer array element in the ultrasonic phased array module controls sound beam focusing and energy distribution through a phase delay controller, and carries out the stripping of graphite oxide flowing in a flow channel; a micro-Raman spectrometer in the micro-fluidic-Raman detection module collects characteristic peak data of a graphene oxide sheet layer in a micro-fluidic chip in real time and sends the characteristic peak data to a signal analysis unit; and the feedback control module is used for receiving the layer number distribution data output by the signal analysis unit, dynamically adjusting ultrasonic parameters of the phase delay controller, and controlling the diverter valve to guide substandard products into a secondary treatment channel and finally return the substandard products to the flow channel for stripping again. The system and the method for stripping the graphene oxide based on coupling of the ultrasonic phased array and the micro-fluidic chip have the advantages of efficient stripping, accurate detection, closed-loop optimization and the like.

A system for chip-removing machining of a workpiece and for measuring and evaluating force and torque during the chip-removing machining of the workpiece includes a machine tool with a tool for chip-removing machining of the workpiece; a device for measuring force and torque that includes a plurality of piezoelectric transducers generating polarization charges being communicated through a respective measuring channel; and a stationary evaluation unit for evaluating measured value data of the device. The device includes a measuring unit installed in the machine tool and rotates with the tool about an axis of rotation during chip-removing machining. The device includes a control unit that transmits measured values as measured value data in a wireless manner directly to the evaluation unit with a transmission power in the range of 0.1 mW to 10 mW.

The invention discloses a multi-medium sound field control system based on an AI algorithm, which belongs to the field of intelligence and comprises a data acquisition module, a sound field modeling module, an AI optimization control module, a self-adaptive adjustment module, a hardware execution module and the like. The data acquisition module is used for sampling and acquiring acoustic signals in air, water and a solid medium; the sound field modeling module is combined with a finite difference time domain method and a graph neural network to accurately simulate sound wave propagation; the AI optimization control module fuses near-end strategy optimization and a differential evolution algorithm to generate an optimal excitation parameter; the adaptive adjustment module is based on a model migration and contrast learning mechanism; the hardware execution module generates a controllable sound field by using a piezoelectric transducer array; and the feedback evaluation module passes back measurement data through laser vibration measurement and a microphone array to realize closed-loop correction of control parameters. The method has the advantages that high-precision sound wave modeling, intelligent control parameter optimization and dynamic self-adaptive adjustment capacity are achieved, and the real-time performance, stability and the like of sound field control in the multi-medium environment are improved.

The invention provides a uniform tin droplet target generating device for inhibiting axial shaking of tin droplets, which comprises a crucible, tin melt, a nozzle, a heating assembly and a disturbance assembly, the tin melt is located inside the crucible, and the heating assembly is located outside the crucible and is used for heating the tin melt in the crucible; the nozzle is located at the bottom of the crucible and used for spraying uniform tin liquid drops and reducing axial shaking of the tin liquid drops. The disturbance assembly comprises a signal generator, a piezoelectric transducer and a vibration transmission rod, the vibration transmission rod is located in the molten tin, the piezoelectric transducer is located above the crucible and connected with the vibration transmission rod through a connecting piece, and the signal generator is connected with the piezoelectric transducer; a sine disturbance signal generated by the signal generator is provided for the vibration transmission rod through the piezoelectric transducer, and the disturbance signal is transmitted into molten tin through the vibration transmission rod, so that the jetted tin jet flow is broken into uniform liquid drop flow; according to the device provided by the invention, the distance between the liquid drops can be regulated and controlled; the designed nozzle can reduce the axial jitter of the liquid drop flow and increase the axial stability of the liquid drop.

The invention belongs to the technical field of fluid control and atomization, and particularly relates to a main control system, a liquid supply system, a generation system and an auxiliary system. The generating system comprises a water storage tank, a porous steel sheet arranged at the bottom of the water storage tank, conical micropores formed in the porous steel sheet, a piezoelectric transducer fixed to the bottom of the porous steel sheet, a soaking copper plate arranged at the top of the water storage tank and an electric heating layer installed on the soaking copper plate. Due to the fact that an existing annular transducer cannot meet the requirement for generation of a single water drop or multiple water drops and cannot meet the requirement for accurate and controllable sizes of the water drops, a rectangular transducer pair is adopted as an excitation device, surface wave superposition can be generated through vibration of the transducer, meanwhile, the liquid level of a water storage tank is controllable, and the energy storage efficiency is improved. High-temperature pulses are applied to the air layer on the upper surface of the water layer, so that the pressure in the water tank is controllable during spraying, and inconsistent diameters of water drops caused by uncontrollable pressure are avoided.

The invention provides a resonator, a filter and electronic equipment. Relates to the technical field of resonators. The resonator can improve the electromechanical coupling coefficient. The resonator can comprise a substrate, a first electrode, a piezoelectric transduction layer and a plurality of second electrodes, the first electrode, the piezoelectric transduction layer and the multiple second electrodes are arranged on the substrate, the piezoelectric transduction layer is provided with a first side and a second side, the multiple second electrodes are located on the first side and are arranged side by side in the first direction, the first electrode is located on the second side, the first side deviates from the substrate, and the second side faces the substrate; the piezoelectric transduction layer comprises a first piezoelectric layer and a second piezoelectric layer which are stacked; the first piezoelectric layer has a first piezoelectric tensor component e33, the second piezoelectric layer has a second piezoelectric tensor component e33, and the first piezoelectric tensor component e33 and the second piezoelectric tensor component e33 are opposite. By using the adjacent piezoelectric layers with opposite piezoelectric tensor components e33, the resonator can have large vibration so as to improve the electromechanical coupling coefficient.

The invention discloses an ultrasonic fingerprint identification method, a chip, a system, electronic equipment and a storage medium, and the method comprises the steps: controlling an ultrasonic piezoelectric transducer to work based on first configuration information, and obtaining one or more first fingerprint images; performing spatial frequency identification on the one or more first fingerprint images, and determining a first spatial frequency corresponding to the one or more first fingerprint images; when one or more first fingerprint images meet the adaptive condition, determining second configuration information based on the first spatial frequency and the first configuration information; and updating the first configuration information by adopting the second configuration information. According to the method, the first configuration information is dynamically adjusted based on the first spatial frequency corresponding to the first fingerprint image, so that the adjusted second configuration information can effectively guarantee the overall performance of the ultrasonic fingerprint system, the quality of the fingerprint image acquired subsequently is improved, the recognition effect is improved, and the universality of the system is improved.

The present disclosure provides a piezoelectric transducer and a pressure sensing button. The piezoelectric transducer includes as follows: A piezoelectric ceramic having a shape of a sheet. An upper elastic sheet and a lower elastic sheet disposed on two opposite sides of the piezoelectric ceramic, respectively. Two ends of the upper elastic sheet are fixed to an upper surface of the piezoelectric ceramic. Two ends of the lower elastic sheet are fixed to a lower surface of the piezoelectric ceramic. A plurality of resistive layers fixed to the upper elastic sheet and the lower elastic sheet, respectively, and the plurality of resistive layers are electrically connected to each other to form a bridge structure. The piezoelectric transducer of the present disclosure can recognize the external force applied to the pressure sensing button through the resistance change and realize the pressure change detection.

The invention specifically discloses an ultrasonic guided wave edge real-time communication method and system based on an FPGA (Field Programmable Gate Array), and the method comprises the following steps: the FPGA of a guided wave communication transmitting circuit receives data needing to be transmitted, completes the data package construction and carrier modulation, and outputs a digital signal; after digital-to-analog conversion, a multi-stage power amplification circuit and a matching network circuit, the ultrasonic guided waves are transmitted to an excitation piezoelectric transducer, and the excitation piezoelectric transducer generates ultrasonic guided waves to be transmitted in a metal medium; the receiving piezoelectric transducer converts ultrasonic guided waves transmitted in a metal medium into piezoelectric signals, the piezoelectric signals sequentially pass through the active filter circuit, the variable gain amplification circuit and the analog-to-digital conversion circuit and are transmitted to the FPGA of the guided wave communication receiving circuit in the form of digital quantity, and the FPGA operates a demodulation algorithm to restore effective binary data. And the data is transmitted to other equipment. According to the technical scheme, the FPGA serves as a processing unit, high-frequency carrier modulation and real-time operation of a complex demodulation algorithm can be completed, and the high-speed communication requirement can be met.

A conformable piezoelectric transducer array for performing ultrasound or the like includes a silicone elastomer substrate and a silicone elastomer superstrate. A plurality of piezoelectric transducer elements are disposed between the substrate and superstrate. A first electrical interconnect layer electrically interconnects a first surface of the transducer elements adjacent to the substrate and a second electrical interconnect layer electrically interconnecting a second surface of the transducer elements adjacent to the superstrate.

The invention provides a bulk acoustic wave resonator, a filter and electronic equipment. The bulk acoustic wave resonator comprises a substrate layer, a Bragg reflection layer arranged on the substrate layer and a piezoelectric transduction structure layer arranged on the Bragg reflection layer. The Bragg reflection layer comprises a plurality of film layers which are arranged in a stacked mode, and the refractive indexes of every two adjacent film layers are different; the piezoelectric transduction structure layer comprises a piezoelectric layer and an electrode layer which are stacked; at least one film layer, close to the piezoelectric transduction structure layer, in the Bragg reflection layer is a preset film layer, the preset film layer comprises cavity parts and supporting parts, the cavity parts and the supporting parts are alternately arranged in the first direction, and the first direction is parallel to the substrate layer. According to the bulk acoustic wave resonator, acoustic wave energy is concentrated on the piezoelectric layer through the cavity parts, the electromechanical coupling coefficient of the bulk acoustic wave resonator is increased, under the alternate arrangement of the cavity parts and the supporting parts, the slowness curve of the main vibration mode of the bulk acoustic wave resonator is flattened, the transverse mode and stray response are restrained, and therefore the quality factor of the bulk acoustic wave resonator is improved.

Fluid analyzation devices, methods, and systems are disclosed including an analyzation device comprising a sample vessel having an outer surface, a microchannel within the confines of the outer surface, a first port extending through the outer surface to the microchannel, and a second port extending through the outer surface to the microchannel; and an piezo transducer bonded to the outer surface of the sample vessel to form a monolithic structure, the piezo transducer configured to emit ultrasonic acoustic waves having a first frequency, a second frequency, and a third frequency into and / or to a blood sample within the microchannel, the first frequency configured to begin separation of red blood cells and plasma in the blood sample, the second frequency configured to complete separation of the red blood cells and plasma, and the third frequency configured to rupture cell walls of the blood cells producing a lysed blood sample.

The invention discloses a longitudinal bending composite type six-degree-of-freedom piezoelectric active vibration isolation platform and a working method thereof. The vibration isolation platform adopts a modular structural design, a vibration isolation connecting platform and a base platform are sequentially arranged from top to bottom and are connected through four uniformly distributed vibration isolation modules, and each vibration isolation module forms a multi-stage vibration transmission structure through a fixed base, a transducer base, a piezoelectric transducer, an amplitude-change pole, a pre-tightening bolt and a small flexible hinge. The control module collects feedback signals of a first acceleration sensor arranged on the vibration isolation connecting platform and feedforward signals of a second acceleration sensor arranged on the base platform, and outputs 12-channel control signals to the piezoelectric transducers of the vibration isolation modules after signal processing. The piezoelectric transducer is driven to generate a composite motion mode of longitudinal vibration and multidirectional bending vibration, and active suppression of longitudinal vibration and radial bending vibration in any direction of a vibration isolation object is achieved. The device has the advantages of multi-degree-of-freedom vibration isolation, compact structure, lightweight design, independent control, high stability and the like, and has important application value in the fields of space reflecting mirrors, micro-nano manufacturing equipment vibration control and multi-degree-of-freedom vibration isolation systems.

The invention discloses a double-cantilever-beam piezoelectric vibration energy collector based on an annular steady state, which comprises a piezoelectric transducer, an elastic cantilever beam, a magnet and a base, after the piezoelectric transducer is mounted on the elastic cantilever beam to form a double-layer composite cantilever beam, the magnet is mounted at the free end of the double-layer composite cantilever beam, nonlinear coupling is carried out through repulsive magnetic force, and the piezoelectric transducer is connected with the base. The two-dimensional annular potential well structure with the adjustable potential well is formed, and the energy collector can easily trigger large-amplitude inter-well movement through the potential well structure. Through the nonlinear coupling induced internal resonance effect, inter-well energy transfer and two-dimensional potential well modulation are realized, and vibration energy can be efficiently captured in a broadband without a large amount of energy input or a complex structure. According to the design, the collection efficiency of low-frequency, low-intensity and multi-direction environment vibration energy in a wide working bandwidth is good.

The invention discloses an oscillation microbubble chip, a separation system and an acoustic manipulation method, the device utilizes the acoustic eddy current effect induced by oscillation microbubbles to realize micro-nano particle acoustic manipulation, the chip structure and operation are simple, the biocompatibility is high, and by designing the chip structure, due to the breathable and water-repellent characteristics of PDMS and the surface tension of fluid, the micro-nano particle acoustic manipulation can be realized. Alternatively arranged equilateral triangle column cavities with different sizes are formed on the side wall of the PDMS microfluidic channel to anchor bubbles. Bubble oscillation is driven by bulk acoustic waves generated by exciting a piezoelectric transducer through a signal generator, symmetrical vortexes are formed on the surfaces of the bubbles through secondary acoustic radiation force generated by bubble oscillation, then large-size particles are captured, and small-size particles flow to an outlet along with flowing under the action of drag force. Gradient separation is adopted to separate small particles from a mixed solution and enrich large particles, enrichment, separation and other control of microparticles are achieved through the acoustic vortex field effect of a specific structure, great potential is achieved in biological research, the structure is simple, the equipment cost is low, and integration is easy.

An apparatus for mitigating contamination in a fuel supply is an ultrasonic generator coupled with a piezoelectric transducer that propagates ultrasonic waves through a fuel tank. In some embodiments the apparatus is used to mitigate the growth of microbial organisms. In other embodiments the apparatus is used to emulsify water into the fuel, particularly in diesel fuel. The apparatus addresses water and microbial growth found in boats, cars, and aircraft as well as in storage tanks such as those used at fuel stations. In some embodiments, the fluid is diesel fuel.

A system is provided including one or more piezoelectric assemblies, where the one or more piezoelectric assemblies include a plurality of piezoelectric transducers. The system includes amplifier circuitry coupled to the plurality of piezoelectric transducers and configured to provide an alternating-current (AC) voltage signal to one or more piezoelectric transducers of the plurality of piezoelectric transducers, based on a target configuration associated with removing regolith dust from a vehicle operable in a space environment. The one or more piezoelectric transducers are configured to vibrate based on a magnitude and a frequency of the AC voltage signal.

The invention provides an acoustic resonator, a filter and electronic equipment. The acoustic resonator comprises a substrate layer, a piezoelectric transduction structure layer and an energy adjusting layer, the piezoelectric transduction structure layer is arranged on one side of the substrate layer; the energy adjusting layer is arranged between the substrate layer and the piezoelectric transduction structure layer, the energy adjusting layer comprises a plurality of binding grooves, and each binding groove at least penetrates through the surface, facing the piezoelectric transduction structure layer, of the energy adjusting layer. Through the binding grooves which are arranged at intervals and penetrate through the surface, facing the piezoelectric transduction structure layer, of the energy adjusting layer, sound wave energy is concentrated on the piezoelectric transduction structure layer, leakage of the sound wave energy towards the substrate layer is reduced, and the electromechanical coupling coefficient of the acoustic resonator is improved; the piezoelectric transduction structure layer is supported, collapse of the piezoelectric transduction structure layer is avoided, the situation that the power capacity of the acoustic resonator is reduced is reduced, and therefore the power capacity and the electromechanical coupling coefficient of the acoustic resonator are improved.

An ultra-high-cell-density multicellular tissue lifting bioprinting device assisted by oblique incident bulk wave and a printing method therefor are provided, and the printing device includes a printing liquid tank, a printing platform, a light source and an oblique incident bulk wave chip; the printing liquid tank contains a printing liquid which is a mixture of cells and a photocurable bioink; the printing platform is arranged horizontally and extends into the printing liquid tank to come into contact with the printing liquid; the printing platform is capable of going up and down; the light source is arranged under the printing liquid tank, and light enters the printing liquid tank; the oblique incident bulk wave chip is a piezoelectric transducer arranged obliquely; the piezoelectric transducer is arranged under the printing liquid tank and tilted relative to the horizontal plane to generate an oblique incident bulk wave acoustic field in the printing liquid.

The invention provides a piezoelectric transducer and method for directionally exciting and receiving non-dispersion torsional guided waves, and relates to the technical field of ultrasonic nondestructive testing, the piezoelectric transducer comprises a first circumferential array, and the first circumferential array is composed of a plurality of first piezoelectric units and a plurality of first time delay units; and the second circumferential array is composed of a plurality of second piezoelectric units and a plurality of second time delay units. The piezoelectric transducer capable of directionally exciting and receiving the non-dispersion torsional guided wave is constructed through the thickness shearing type piezoelectric unit and the height difference time delay unit, no matter unidirectional excitation or unidirectional receiving is needed, an additional circuit or equipment is not needed to provide time delay, and the complexity and cost of the whole structure are reduced. In addition, the time delay unit is adopted to replace a piezoelectric unit to be in curved surface combination with the pipeline, the problem that the piezoelectric unit is not matched with the detected pipeline due to too small flexibility can be avoided, then the fitting degree is improved, signal transmission is guaranteed, and detection is more efficient and accurate.

Embodiments of the present disclosure provide an ultrasonic fingerprint identification apparatus and a lamination thickness adjustment method therefor, and an electronic device, and relate to the technical field of fingerprint identification. A specific embodiment of the ultrasonic fingerprint identification apparatus comprises: an integrated chip and a piezoelectric transducer, wherein a back surface of the integrated chip is connected to an application layer, and the piezoelectric transducer is located on a surface of the integrated chip. Through excitation of a driving pulse, the piezoelectric transducer transmits an ultrasonic signal to the application layer through the integrated chip, and a signal receiving circuit of the integrated chip receives an ultrasonic echo signal returned from a finger through the application layer. The embodiment can avoid an interference effect of surface defects of a lamination on fingerprint imaging, and improve accuracy of fingerprint identification.

Ultrasonic sensors, sensor controllers, and sensor control methods are provided with self-cleaning functionality. An illustrative method includes: driving a piezoelectric transducer to generate a short acoustic burst for obstacle detection or distance measurement; obtaining a receive signal to monitor for reflections of the short acoustic burst; and operating to clean the sensor by driving the piezoelectric transducer to generate a long acoustic burst at a resonant frequency of the piezoelectric transducer. The method may be implemented by a sensor controller having a transmitter configured to drive the piezoelectric transducer, a receiver coupled to the piezoelectric transducer and a microphone to detect a reflection of the acoustic burst within a measurement interval associated with the acoustic burst; and a microcontroller configured to control a length of the acoustic burst. The sensor controller may be incorporated into a sensor that also includes a piezoelectric transducer and optionally includes one or more microphones.

The invention provides an ultrasonic parameter adaptive adjustment and cleaning evaluation method in a wafer cleaning process, and relates to the technical field of semiconductor manufacturing, and the method comprises the steps: calculating sound field energy distribution through collecting wafer surface temperature distribution and cavity vibration response data; based on the temperature gradient and the sound intensity gradient, calculating the micro-flow field distribution of the cleaning fluid, and establishing a cavitation bubble collapse characteristic matrix; recognizing and cleaning a dead zone through singular value decomposition of the feature matrix, and controlling a piezoelectric transducer to generate focused ultrasonic waves; meanwhile, the plasma resonance sensor is used for monitoring the surface adsorption characteristic change and evaluating the cleanliness. According to the invention, real-time self-adaptive adjustment of ultrasonic cleaning parameters is realized, and the cleaning uniformity and efficiency are improved.

Machine Learning based scaling estimation in the art mostly used a complex guided wave setup. Further, selection of features for ML is critical to the predict significant points on the US signal response providing appropriate but minimum features that capture maximum scaling characteristics, thus keeping the ML features minimal to provide time and resource efficient computation. A method and system for estimation of scaling in objects by processing ultrasound responses using ML is disclosed. The system uses low-voltage pulse packets to generate ultrasonic (US) waves, capable of penetrating metal structures, using an economically repurposed piezoelectric transducer. These US signal response from the object-scaling interface and scaling-fluid interface, is captured using the repurposed piezoelectric transducer and processed to generate the envelope of the US signal response, and unique 42 features are extracted. A pretrained ML model processes the features to estimate various levels of scaling present in the object.

The present invention relates to an ultrasonic sensor (5) and a vehicle, wherein the ultrasonic sensor (5) comprises: a housing (10), a diaphragm cup (20), and a piezoelectric transducer (30), wherein the diaphragm cup (20) has a substantially cylindrical wall (22) and an oscillatable diaphragm (25) and is formed on the basis of a polymer, wherein the piezoelectric transducer (30) is integrated into the diaphragm (25) in that the piezoelectric transducer (30) is completely covered by the polymer of the diaphragm (25), and wherein the diaphragm cup (20) is at least partially inserted into the housing (10) and fastened to the housing (10).

The invention relates to the technical field of solid plate defect detection, in particular to a solid plate defect detection method based on Lamb wave end face echoes, which comprises the following steps: exciting and receiving wedge piezoelectric transducers are arranged on the same side of a solid plate, exciting and receiving a single-mode Lamb wave signal, and acquiring a multi-path signal comprising a direct wave, a side face echo and a defect reflection echo; by analyzing the difference between a direct wave and a side echo, a defect reflection signal is extracted, and by combining the time difference between the defect reflection signal and the side echo and the Lamb wave propagation speed, a geometric model is established, and the defect position is accurately calculated. By adjusting the position of a transducer, the time difference between a defect reflected wave and a direct wave is constant, a defect echo amplitude value is obtained under the equal propagation condition and compared with a standard test block amplitude value, a mapping relation between the amplitude value and the size is constructed, and accurate quantification of the defect size is achieved.