Method and device for dynamically measuring sound field of transducer based on array mark optical imaging

Abstract

The invention discloses a transducer sound field dynamic measurement method and device based on array marking optical imaging, and relates to the technical field of ultrasonic transducers, and the method comprises the steps: obtaining a vibration image sequence; the vibration image sequence is obtained by an experiment for driving an ultrasonic transducer to generate ultrasonic waves in a material sample; mark point arrays arranged at equal intervals are prepared on the surface of the material sample; after the ultrasonic excitation module and the optical imaging system are synchronously triggered, a vibration image sequence of the mark point array under the ultrasonic action is captured; calculating plane displacement and out-of-plane displacement of each mark point according to the reference frame and the time sequence image data; according to the plane displacement and the out-of-plane displacement, mapping the three-dimensional displacement time sequence of each mark point to a regular space network to obtain a four-dimensional array; and acquiring sound field parameters and a visualization result according to the four-dimensional array. According to the invention, full-field, synchronous and dynamic three-dimensional displacement measurement can be carried out on the sound field.

Description

Technical Field

[0001] This application relates to the field of ultrasonic transducer technology, and in particular to a method and apparatus for dynamic measurement of transducer acoustic field based on array marker optical imaging. Background Technology

[0002] The development of modern industry has placed extremely high demands on the safe operation of critical equipment and structures (such as pressure pipelines, aerospace components, and railway tracks). Non-destructive testing (NDT), a technique that inspects the surface or internal structure of an object without damaging or affecting its performance, has become an indispensable core means of ensuring industrial safety and improving product quality. Currently widely used NDT methods include radiographic testing, magnetic particle testing, penetrant testing, eddy current testing, and ultrasonic testing. Among these methods, ultrasonic testing is widely recognized as one of the most important and universal NDT techniques due to its strong penetrating power, high detection sensitivity, accurate defect localization, and harmlessness to humans. It evaluates and measures the internal structure of a workpiece by emitting ultrasonic waves into the workpiece and receiving the echoes reflected from defects or interfaces.

[0003] The core component of an ultrasonic testing system is the ultrasonic transducer, whose performance directly determines the capabilities of the entire system. The acoustic field characteristics generated by the transducer (including energy distribution, focusing characteristics, near-field / far-field behavior, diffusion angle, etc.) play a decisive role in the detection resolution, signal-to-noise ratio, and accuracy of defect quantification. Therefore, accurate measurement and characterization of the ultrasonic transducer's acoustic field are crucial for evaluating its performance, guiding its optimized design, and ultimately ensuring the reliability of the test results.

[0004] The acoustic field characteristics of ultrasonic transducers play a decisive role in their detection performance. However, existing acoustic field measurement techniques (such as scanning laser Doppler vibrometers) have inherent drawbacks, including low measurement efficiency, inability to capture transient acoustic fields, and lack of spatial synchronization. These drawbacks make it difficult to accurately and efficiently characterize the three-dimensional spatiotemporal distribution characteristics of the transducer's acoustic field, and thus cannot provide a comprehensive and effective basis for the optimal design and performance evaluation of the transducer. Summary of the Invention

[0005] The purpose of this application is to provide a method and device for dynamic measurement of transducer sound field based on array marker optical imaging, which can realize full-field, synchronous, and dynamic three-dimensional displacement measurement of sound field, providing a more reliable and comprehensive technical means for transducer sound field analysis, modal identification and performance optimization.

[0006] To achieve the above objectives, this application provides the following solution: In a first aspect, this application provides a method for dynamic measurement of the acoustic field of a transducer based on array-marked optical imaging, including: A vibration image sequence is acquired; the vibration image sequence includes: a reference frame and time-series image data; the vibration image sequence is obtained by an experiment in which an ultrasonic transducer is driven to generate ultrasonic waves in a material sample; an array of equally spaced markers is prepared on the surface of the material sample; after synchronously triggering the ultrasonic excitation module and the optical imaging system, the vibration image sequence of the marker array under ultrasonic action is captured; the ultrasonic excitation module is used to drive the ultrasonic transducer to generate ultrasonic waves in the material sample; the optical imaging system is used to capture the vibration image sequence of the marker array under ultrasonic action; Calculate the planar displacement and out-of-plane displacement of each marker point based on the reference frame and time-series image data; Based on the planar displacement and the out-of-plane displacement, the three-dimensional displacement time series of each marker point is mapped to a regular spatial network to obtain a four-dimensional array; The sound field parameters and visualization results are obtained based on the four-dimensional array.

[0007] Optionally, the sound field parameters are obtained from the four-dimensional array, specifically including: By using the formula for calculating sound energy distribution, the squares of displacements at all time points are summed to obtain the relative sound energy density distribution at each marker point; Based on the four-dimensional array, the time difference between the arrival of the wavefront at two reference points is calculated using a cross-correlation algorithm or a wavefront peak tracking method; the two reference points are two reference points selected along the main direction of the sound beam. The wave velocity is calculated based on the time difference and the positions of the two reference points. Based on the relative acoustic energy density distribution, an energy distribution curve is extracted along the main direction of the sound beam; Based on the relative acoustic energy density distribution, a point far from the near-field region is selected to obtain the diffusion angle calculation point; Along the arc direction with the diffusion angle calculation point as the radius, determine the two points where the energy on both sides drops to the first energy, and obtain the upper point and the lower point; the first energy is half of the energy at the diffusion angle calculation point; The width of the sound beam in the main direction is determined based on the distance between the upper and lower points; The diffusion angle is calculated based on the width of the sound beam in the main direction and the distance from the origin; the distance from the origin is the distance between the diffusion angle calculation point and the origin; the origin is the position of the ultrasonic transducer.

[0008] Optionally, obtaining the visualization result based on the four-dimensional array specifically includes: The four-dimensional array is visualized using pseudo-color encoding, three-dimensional vector field display, or volume rendering methods to generate a three-dimensional dynamic visualization sequence.

[0009] Optionally, acquiring the vibration image sequence specifically includes: Obtain a sequence of vibration images within a set sound field measurement range; the set sound field measurement range is determined based on the characteristics of the ultrasonic transducer.

[0010] Secondly, this application provides a transducer acoustic field dynamic measurement device based on array marker optical imaging, including: an ultrasonic excitation module, an optical imaging system, a synchronous triggering unit, and a signal processing and reconstruction module. The ultrasonic excitation module is used to drive the ultrasonic transducer to generate ultrasonic waves in the material sample; the surface of the material sample is prepared with an array of equally spaced marker points. The optical imaging system is used to capture a vibration image sequence of the marker array under ultrasonic action; the vibration image sequence includes: a reference frame and time-series image data; The synchronization triggering unit is used to generate a synchronization triggering signal; the synchronization triggering signal is used to synchronously trigger the ultrasonic excitation module and the optical imaging system. The signal processing and reconstruction module is used for: Calculate the planar displacement and out-of-plane displacement of each marker point based on the reference frame and time-series image data; Based on the planar displacement and the out-of-plane displacement, the three-dimensional displacement time series of each marker point is mapped to a regular spatial network to obtain a four-dimensional array; The sound field parameters and visualization results are obtained based on the four-dimensional array.

[0011] Optionally, the array spacing of the marker point array is less than half the wavelength of the ultrasonic wave.

[0012] Optionally, the frame rate of the optical imaging system is greater than twice the maximum value of the excitation frequency generated by the ultrasonic excitation module, and the image resolution satisfies that each marker point covers 3-5 pixels.

[0013] Thirdly, this application provides a computer device, including: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the transducer acoustic field dynamic measurement method based on array marker optical imaging as described above.

[0014] Fourthly, this application provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the transducer acoustic field dynamic measurement method based on array marker optical imaging as described above.

[0015] Fifthly, this application provides a computer program product, including a computer program that, when executed by a processor, implements the transducer acoustic field dynamic measurement method based on array marker optical imaging as described above.

[0016] According to the specific embodiments provided in this application, the following technical effects are disclosed: This application provides a method and apparatus for dynamic measurement of transducer acoustic field based on array-marked optical imaging. The method includes: acquiring a vibration image sequence; the vibration image sequence includes a reference frame and time-series image data; the vibration image sequence is obtained by an experiment in which an ultrasonic transducer is driven to generate ultrasonic waves in a material sample; an array of equally spaced markers is prepared on the surface of the material sample; after synchronously triggering an ultrasonic excitation module and an optical imaging system, the vibration image sequence of the marker array under ultrasonic action is captured; the ultrasonic excitation module is used to drive the ultrasonic transducer to generate ultrasonic waves in the material sample; the optical imaging system is used to capture the vibration image sequence of the marker array under ultrasonic action; the planar displacement and out-of-plane displacement of each marker point are calculated based on the reference frame and time-series image data; based on the planar displacement and the out-of-plane displacement, the three-dimensional displacement time sequence of each marker point is mapped to a regular spatial network to obtain a four-dimensional array; and the acoustic field parameters and visualization results are obtained based on the four-dimensional array. This application abandons the "point scanning" approach and directly measures the entire measurement area, using an optical imaging system to simultaneously observe the entire two-dimensional array composed of markers. This means that at the instant of ultrasonic excitation, a single frame of the imaging system records the state of all marker points within the entire field of view at the same moment. Through continuous imaging, a data cube is obtained, which naturally contains complete spatial and temporal information, thereby enabling full-field, synchronous, and dynamic three-dimensional displacement measurement of the sound field. This provides a more reliable and comprehensive technical means for transducer sound field analysis, modal identification, and performance optimization. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is an application environment diagram of a transducer acoustic field dynamic measurement method based on array marker optical imaging according to an embodiment of this application.

[0019] Figure 2 This is a flowchart illustrating a method for dynamic measurement of transducer acoustic field based on array marker optical imaging, as provided in Embodiment 1 of this application.

[0020] Figure 3 This is a schematic diagram of the structure and arrangement of an experiment in which an ultrasonic transducer is driven to generate ultrasonic waves in a material sample, as provided in Embodiment 1 of this application.

[0021] Figure 4 This is a schematic diagram of wave velocity extraction provided in Embodiment 1 of this application.

[0022] Figure 5 This is a schematic diagram of the extraction diffusion angle provided in Embodiment 1 of this application.

[0023] Figure 6 This is a schematic diagram of the control flow of the transducer acoustic field dynamic measurement device based on array marker optical imaging provided in Embodiment 2 of this application.

[0024] Figure 7 This is a flowchart illustrating a method for dynamic measurement of transducer acoustic field based on array marker optical imaging, as provided in Embodiment 3 of this application.

[0025] Figure 8 This is a schematic diagram of the sound wave fluctuation in the specimen at a certain moment, provided in Embodiment 3 of this application.

[0026] Figure 9 This is a schematic diagram of the structure of a computer device provided in an embodiment of this application. Detailed Implementation

[0027] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0028] Currently, the research and evaluation of sound field characteristics mainly rely on finite element method (FEM) simulation and analytical modeling. While these numerical methods can provide some theoretical insights, their accuracy heavily depends on the precision of the input material parameters and boundary conditions, and they are computationally expensive and difficult to realistically reproduce actual working conditions. In terms of experimental measurement, existing methods mainly include scanning measurement methods based on hydrophones, ultrasonic transducers, and laser vibrometers. Among these, hydrophones are only suitable for underwater measurements and cannot be applied to sound field measurements of solid materials; ultrasonic transducers suffer from problems such as unstable coupling and low spatial resolution; and although laser Doppler vibrometers (LDV) can perform non-contact nanoscale measurements, they can only measure one point at a time. For sound field measurements covering an area, point-by-point scanning is still required, making the measurement of the entire sound field extremely time-consuming.

[0029] Therefore, this application provides a method for non-contact, full-field, rapid, and high-precision measurement and visualization of ultrasonic wave propagation on the surface of solid materials. This method overcomes the inefficiency of existing point scanning techniques, providing crucial experimental data support and technical means for sensor design optimization, performance evaluation, standardization, and ultimately reliable application in complex industrial scenarios.

[0030] The prior art related to this application is a scanning laser Doppler vibrometer used for acoustic field measurement of ultrasonic transducers. Its core technical solution lies in performing point-by-point measurements using a sequentially moving laser focus, assuming the acoustic field is stable and repeatable, and finally reconstructing the acoustic field distribution through post-synthesis. Specifically: a signal generator produces a continuous or repetitive periodic electrical signal to drive the ultrasonic transducer to repeatedly excite an ultrasonic field in the specimen; the LDV system emits a focused laser beam, and a computer-controlled galvanometer system sequentially and point-by-point positions the laser focus to a point on a pre-set measurement grid on the specimen surface; at each measurement point, the vibration velocity or displacement is measured based on the Doppler effect, and multiple excitation averagings are performed to improve the signal-to-noise ratio; after completing the measurement of one point, the laser focus is moved to the next point, and the process is repeated until all points are measured. Finally, software combines all the single-point data collected at different time points to synthesize the acoustic field distribution map of the entire measurement area.

[0031] This technique employs a combination of "sequential point-by-point scanning" and "repeated excitation averaging." This characteristic requires the ultrasonic transducer to be excited countless times with perfect uniformity, and the responses at each point to be averaged and synthesized. However, in reality, minute fluctuations in transducer performance and inhomogeneities in the specimen material mean that the sound field generated by each excitation is not absolutely consistent. This forced averaging process homogenizes the instantaneous fluctuations in the sound field, failing to accurately reflect the true state of the sound field under a single excitation and reducing the fidelity of the measurement results.

[0032] This technology reconstructs the sound field by measuring different points in space at different times and then synthesizing the data. This approach implicitly assumes that the system is absolutely stable throughout the entire process. However, factors such as thermal deformation caused by changes in ambient temperature and energy drift of the excitation source during the several-hour measurement process introduce uncorrectable systematic errors between the data measured at different times. This disrupts the spatial consistency of the sound field phase information, making sound field analysis and modal identification unreliable.

[0033] This technology achieves non-contact measurement through laser scanning using a high-precision mechanical galvanometer. This approach relies on complex optical paths and moving parts to achieve micron-level positioning, directly resulting in a complex system structure, large size, and high cost. Furthermore, the lengthy scanning time requires the system to operate within a highly stable vibration-isolated platform and a temperature-controlled laboratory, significantly limiting its deployment and application in noisy industrial environments with limited temperature control.

[0034] The fundamental flaw in existing technology stems from its "sequential point-by-point scanning": Problem 1 (inefficiency) stems from the "point-by-point" mechanism. Measuring N points requires stimulating N points and moving them N-1 times.

[0035] Problem 2 (inability to capture transient fields): This is a direct consequence of Problem 1. Because a single measurement takes too long, far exceeding the duration of a transient ultrasonic pulse (usually in the range of microseconds to milliseconds), it is physically impossible to capture the transient process.

[0036] Problem 3 (Lack of Spatial Synchronization): This stems from the "sequential" mechanism. Because data from different spatial points are collected at different times, it means we can never know what the complete spatial distribution of the entire sound field looks like at a specific time t. This disrupts the spatiotemporal correlation of the sound field data.

[0037] This application abandons the "point scanning" approach and measures the entire measurement area using a high-speed optical imaging system to simultaneously observe a two-dimensional array of marker points. This means that at the instant of ultrasonic excitation, a single frame of the imaging system records the state of all marker points within the entire field of view at the same moment. Through continuous imaging, a data cube I(x, y, z, t) is obtained, which naturally contains complete spatial and temporal information.

[0038] A single exposure can capture all the data in the field, so the total time required to complete a measurement no longer depends on the number of points N, but only on the number of frames (i.e., the duration) to be acquired, thus improving measurement efficiency. The short total acquisition time allows the system to completely record the entire process of transient sound fields from their generation to their disappearance. This solves the problem of "inability to capture transient fields" and also addresses the problem of "lack of spatial synchronization."

[0039] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0040] The transducer acoustic field dynamic measurement method based on array marker optical imaging provided in this application can be applied to, for example... Figure 1In the application environment shown, terminal 102 communicates with server 104 via a network. A data storage system can store the data that server 104 needs to process. The data storage system can be set up independently, integrated into server 104, or placed in the cloud or on another server.

[0041] The terminal 102 can be, but is not limited to, various desktop computers, laptops, smartphones, tablets, IoT devices, and portable wearable devices. IoT devices can include smart speakers, smart TVs, smart air conditioners, and smart in-vehicle devices. Portable wearable devices can include smartwatches, smart bracelets, and head-mounted devices. The server 104 can be implemented using a standalone server or a server cluster composed of multiple servers, or it can be a cloud server.

[0042] Example 1: In one exemplary embodiment, such as Figure 2 As shown, a method for dynamic measurement of transducer acoustic field based on array marker optical imaging is provided. This method is executed by a computer device, specifically by a terminal or server alone, or by both a terminal and a server. In this embodiment, the method is applied to... Figure 1 Taking server 104 as an example, the explanation includes the following steps S1 to S4. Wherein: S1. Acquire a vibration image sequence; the vibration image sequence includes: a reference frame and time-series image data; the vibration image sequence is obtained by an experiment in which an ultrasonic transducer is driven to generate ultrasonic waves in a material sample; an array of equally spaced markers is prepared on the surface of the material sample; after synchronously triggering the ultrasonic excitation module and the optical imaging system, the vibration image sequence of the marker array under ultrasonic action is captured; the ultrasonic excitation module is used to drive the ultrasonic transducer to generate ultrasonic waves in the material sample; the optical imaging system is used to capture the vibration image sequence of the marker array under ultrasonic action. In this embodiment, a material with a different optical reflectivity than the sample surface can be used as the marker array, which can be called optical markers.

[0043] Please see Figure 3 First, preparations were made for the experiment of driving an ultrasonic transducer to generate ultrasonic waves in a material sample.

[0044] (1) Preparation of test object. Prepare the ultrasonic transducer to be tested and the material sample, and set the placement point O of the ultrasonic transducer to be tested on the material sample.

[0045] (2) Set the sound field measurement range. Based on the characteristics of the ultrasonic transducer being tested, set the sound field measurement range as follows: Establish a spatial coordinate system The origin is taken at the location where the ultrasonic transducer is placed on the sample. The x-axis and y-axis directions are along two sides of the material sample, and the z-axis direction is perpendicular to the plane of the material sample and pointing upwards. The measurement area is set as follows: arrive .

[0046] (3) Preparation of the marker array. An array of markers arranged regularly with equal spacing is prepared on the surface of the material sample. The array spacing design needs to meet the following requirements. ,in The wavelength of ultrasound is , where This represents the spacing along the x-axis. This indicates the spacing along the y-axis.

[0047] (4) Set the optical imaging system parameters. The frame rate setting of the optical imaging system must meet the following requirements. ,in The frame rate of the optical imaging system. To maximize the excitation frequency, the image resolution is set to [value]. Pixels; the image resolution must ensure that each marker point covers at least 3-5 pixels.

[0048] (5) Selection of acquisition method. For cases with a small measurement range, a single sampling method can be selected; for cases where the measurement range exceeds the acquisition range of the optical imaging system, multiple scanning sampling or multiple optical imaging systems can be selected; the optical imaging system is placed above the material sample.

[0049] (6) Acquire a static reference image. Before ultrasonic excitation and dynamic data acquisition, the material sample is in a static, vibration-free state. Acquire a static reference image, which will serve as the reference frame for subsequent displacement calculation. .

[0050] (7) Real-time data acquisition of ultrasonic transducer sound field. The ultrasonic transducer is installed at the designated position O on the material sample, and the ultrasonic excitation module is controlled to excite ultrasonic waves in the material sample through the ultrasonic transducer. The optical imaging system is simultaneously triggered to acquire data using an appropriate acquisition method.

[0051] (8) Data storage. Establish a three-dimensional array. Used to store time-series image data acquired by the optical imaging system, wherein Represents the horizontal coordinate of a pixel. Represents the vertical coordinate of a pixel. Indicates the number of time frames.

[0052] S2. Calculate the planar displacement and out-of-plane displacement of each marker point based on the reference frame and time sequence image data.

[0053] Calculate the planar displacement. Extract the measurement area, and then... Locate each marker point in the middle. For each marker point, a phase correlation or cross-correlation algorithm is used to compare the current frame with the reference frame. By performing matching, the x and y displacements of the marker points on the image plane can be obtained. , .

[0054] Calculate the out-of-plane displacement. For each frame of the dynamic image sequence. Image processing algorithms are used to extract each marker point. The area of ​​the light spot, and its current projected area are accurately calculated. From reference frame Extract the initial projected area of ​​each marker point. ; Calculate the rate of change of the projected area of ​​each frame marker relative to the area of ​​the reference frame. Substitute the calculated rate of change into the calibration curve. Calculate the displacement of the marked point from the surface at the current moment. The displacement from the surface is the displacement along the z-axis.

[0055] S3. Based on the planar displacement and the out-of-plane displacement, map the three-dimensional displacement time series of each marker point to a regular spatial network to obtain a four-dimensional array.

[0056] This embodiment uses spatial interpolation and reconstruction to uniformly map the three-dimensional displacement time series of all marked points to a regular spatial network, establishing a four-dimensional array. Where x and y represent the spatial horizontal and vertical coordinates, z represents the depth coordinates calculated through out-of-plane displacement, and t represents time, this four-dimensional array fully characterizes the dynamic evolution process of the ultrasonic sound field in three-dimensional space and time domain.

[0057] S4. Obtain the sound field parameters and visualization results based on the four-dimensional array.

[0058] Among them, sound field visualization employs pseudo-color encoding, 3D vector field display, or volume rendering methods to visualize the reconstructed four-dimensional array. Visualize the data, generate a 3D dynamic visualization sequence, and export video files for observing the spatial propagation and evolution of the sound field.

[0059] The sound field parameter extraction process is as follows: ① Extract the sound energy distribution. The formula for calculating the sound energy distribution is as follows: The relative acoustic energy density distribution of each spatial point (marked point) is obtained by summing the squares of the displacements at all time points t.

[0060] ② Extract wave velocity. From a four-dimensional array In the middle, the displacement time series of the wavefront is extracted along the main direction of the sound beam (y direction). Set two reference points and (The two reference points are selected along the main direction of the sound beam (y-axis).) The time difference between the arrival of the wavefront at the two reference points is accurately calculated using a cross-correlation algorithm or wavefront peak tracking method. Then wave speed The extraction process is as follows Figure 4 As shown; the selection of the two reference points must meet the following conditions: a) the two points should be located on the main direction (y direction) of the sound beam determined by the sound energy distribution map; b) the two points should be located in the far field region of the transducer sound field to avoid the influence of near field interference effect; c) there should be sufficient distance between the two points to ensure the measurement accuracy of the time difference, thereby ultimately ensuring the calculation accuracy of the wave velocity.

[0061] ③ Extract the diffusion angle. From the relative acoustic energy density distribution diagram... In the middle, an energy distribution curve is extracted along the main direction of the sound beam. Choose a point R (diffusion angle calculation point) far from the near field region. The distance from this point to the origin is r. Take the energy value at this point. Calculate the energy drop on both sides along the vertical direction (x-direction) or along the arc with radius centered at that point. E R The position corresponding to the point (Upper point) and (Lower position), the width of the sound beam in the main direction is... The formula for calculating the diffusion angle is: The extraction process is as follows Figure 5 As shown.

[0062] This embodiment enables non-contact, full-field, dynamic, and high-precision measurement and visualization of the acoustic field characteristics of ultrasonic transducers, allowing for an objective, quantitative, and comprehensive evaluation of transducer performance. This method provides an advanced experimental characterization tool for transducer optimization design, quality control, and application effect evaluation, overcoming the bottlenecks of low efficiency and information gaps in traditional acoustic field measurement techniques. Traditional acoustic field measurement techniques (such as scanning laser vibrometers) are only suitable for single-point scanning measurements of steady-state acoustic fields, and struggle to obtain complete and synchronous full-field information for transient and complex ultrasonic guided wave fields. This embodiment not only acquires dynamic full-process information on sound field propagation but also enables precise parameter extraction and quantitative analysis of various complex acoustic field characteristics, more accurately evaluating transducer performance indicators, particularly solving the problem of difficulty in quantifying and evaluating acoustic field energy distribution, modal purity, and directivity characteristics. In this embodiment, the preparation of the marker matrix and the real-time acquisition of transducer sound field data enable "non-contact, full-field, synchronous, and dynamic" measurement; the calculation of planar displacement and the calculation of out-of-plane displacement enable "nanoscale high-precision" displacement measurement; data reconstruction obtains "three-dimensional dynamic full-process" sound field information; and sound field visualization and sound field parameter extraction enable "sound field visualization and parameter quantification" analysis.

[0063] Example 2: In one exemplary embodiment, such as Figure 6 As shown, a transducer acoustic field dynamic measurement device based on array marker optical imaging is provided, including: an ultrasonic excitation module, an optical imaging system, a synchronous triggering unit, and a signal processing and reconstruction module.

[0064] The ultrasonic excitation module is used to drive the ultrasonic transducer to generate ultrasonic waves in the material sample; the surface of the material sample is prepared with an array of equally spaced markers. The array spacing of the markers is less than half the wavelength of the ultrasonic wave.

[0065] The marker array is prepared by a marker preparation module. The marker preparation module mainly consists of marker array preparation units, which use precision instruments to prepare an array of markers arranged with equal spacing and high precision on the surface of the specimen.

[0066] The optical imaging system is used to capture a sequence of vibration images of the marker array under ultrasonic stimulation. Depending on the measurement range, a single or array-type optical imaging system can be deployed. The vibration image sequence includes a reference frame and time-series image data. The frame rate of the optical imaging system is greater than twice the maximum excitation frequency generated by the ultrasonic excitation module, and the image resolution satisfies that each marker point covers 3-5 pixels.

[0067] The synchronization triggering unit is used to generate a high-precision synchronization triggering signal; the synchronization triggering signal is used to synchronously trigger the ultrasonic excitation module and the optical imaging system to ensure that the start time of sound field excitation and image acquisition is strictly synchronized.

[0068] The signal processing and reconstruction module is responsible for processing the vibration image sequence, executing the core algorithm, and finally outputting sound field parameters and visualization results, as follows: The planar displacement and out-of-plane displacement of each marker point are calculated based on the reference frame and time-series image data.

[0069] Based on the planar displacement and the out-of-plane displacement, the three-dimensional displacement time series of each marker point is mapped to a regular spatial network to obtain a four-dimensional array.

[0070] The sound field parameters and visualization results are obtained based on the four-dimensional array.

[0071] Example 3: In one exemplary embodiment, such as Figure 7 As shown, a method for dynamic measurement of transducer acoustic field based on array-marked optical imaging is provided. This embodiment takes the measurement of SH wave acoustic field excited by an electromagnetic ultrasonic transducer (EMAT) in an aluminum plate as an example. A size of [missing information] is selected. A mm thick aluminum alloy plate was used as the test object, and its surface was polished to form a smooth light-reflecting substrate. A marker array was prepared, with the markers arranged in an equally spaced grid, and the spacing set to... and The spacing between marker points must meet the following requirements. and Set the parameters of the ultrasonic excitation module; the center frequency is... Excitation voltage The number of cycles, T. Sets the frame rate of the optical imaging system. Resolution This ensures that each marker occupies a sufficient number of pixels in the image. Total data acquisition time. It needs to be long enough to cover the main physical processes of ultrasound within the monitoring area.

[0072] Before ultrasonic excitation and dynamic data acquisition, the sample is kept stationary and without vibration, and a static reference image is acquired. A high-precision synchronization signal is generated by the synchronization trigger unit and sent to both the ultrasonic excitation module and the optical imaging system to ensure strict synchronization between the start of ultrasonic wave emission and image acquisition. Under the control of the synchronization trigger signal, the ultrasonic transducer excites ultrasonic waves in the specimen, while the optical imaging system begins acquiring an image sequence. This ultimately yields a set of temporally continuous spatial image sequences. ,in In the signal processing and reconstruction stage, a four-dimensional array is established. This is used to store data on the three-dimensional displacement of each marker point over time, where the z-direction represents the out-of-plane displacement. The obtained... The dataset, after normalization and pseudo-color encoding, can visually display the ultrasonic wave propagation process, including wavefront evolution, interference phenomena, and energy diffusion (e.g., Figure 8 (As shown). Further calculations and processing of the data can extract various physical parameters of the sound field, such as sound velocity, energy flux density, phase distribution, dispersion relation, beam directivity, diffusion angle, and attenuation coefficient, thereby achieving quantitative and accurate characterization of the propagation law of ultrasonic sound field.

[0073] In one exemplary embodiment, a computer device is provided, which may be a server or a terminal, and its internal structure diagram may be as follows. Figure 9 As shown, this computer device includes a processor, memory, input / output (I / O) interfaces, and a communication interface. The processor, memory, and I / O interfaces are connected via a system bus, and the communication interface is also connected to the system bus via the I / O interfaces. The processor provides computational and control capabilities. The memory includes non-volatile storage media and internal memory. The non-volatile storage media stores the operating system, computer programs, and databases. The internal memory provides the environment for the operation of the operating system and computer programs stored in the non-volatile storage media. The I / O interfaces are used for exchanging information between the processor and external devices. The communication interface is used for communicating with external terminals via a network connection. When the computer program is executed by the processor, it implements a method for dynamic measurement of the transducer sound field based on array-marked optical imaging.

[0074] Those skilled in the art will understand that Figure 9 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0075] In one exemplary embodiment, a computer device is also provided, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps in the above-described method embodiments.

[0076] In one exemplary embodiment, a computer-readable storage medium is provided storing a computer program that, when executed by a processor, implements the steps in the above-described method embodiments.

[0077] In one exemplary embodiment, a computer program product is provided, including a computer program that, when executed by a processor, implements the steps in the above-described method embodiments.

[0078] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, data stored, data displayed, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of the relevant data must comply with relevant regulations.

[0079] Those skilled in the art will understand that all or part of the processes in the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments described above. Any references to memory, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take many forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM).

[0080] The databases involved in the embodiments provided in this application may include at least one type of relational database and non-relational database. Non-relational databases may include, but are not limited to, distributed databases based on blockchain. The processors involved in the embodiments provided in this application may be, but are not limited to, general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, quantum computing-based data processing logic devices, etc.

[0081] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0082] This document uses specific examples to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this application. Furthermore, those skilled in the art will recognize that, based on the ideas of this application, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A method for dynamic measurement of the acoustic field of a transducer based on array-marked optical imaging, characterized in that, include: Obtain vibration image sequences; The vibration image sequence includes: a reference frame and time-series image data; the vibration image sequence is obtained by an experiment in which an ultrasonic transducer is driven to generate ultrasonic waves in a material sample; an array of equally spaced markers is prepared on the surface of the material sample; after synchronously triggering the ultrasonic excitation module and the optical imaging system, the vibration image sequence of the marker array under ultrasonic action is captured; the ultrasonic excitation module is used to drive the ultrasonic transducer to generate ultrasonic waves in the material sample; the optical imaging system is used to capture the vibration image sequence of the marker array under ultrasonic action; Calculate the planar displacement and out-of-plane displacement of each marker point based on the reference frame and time-series image data; Based on the planar displacement and the out-of-plane displacement, the three-dimensional displacement time series of each marker point is mapped to a regular spatial network to obtain a four-dimensional array; The sound field parameters and visualization results are obtained based on the four-dimensional array.

2. The method for dynamic measurement of transducer acoustic field based on array marker optical imaging according to claim 1, characterized in that, The sound field parameters are obtained from the four-dimensional array, specifically including: By using the formula for calculating sound energy distribution, the squares of displacements at all time points are summed to obtain the relative sound energy density distribution at each marker point; Based on the four-dimensional array, the time difference between the arrival of the wavefront at two reference points is calculated using a cross-correlation algorithm or a wavefront peak tracking method; the two reference points are two reference points selected along the main direction of the sound beam. The wave velocity is calculated based on the time difference and the positions of the two reference points. Based on the relative acoustic energy density distribution, an energy distribution curve is extracted along the main direction of the sound beam; Based on the relative acoustic energy density distribution, a point far from the near-field region is selected to obtain the diffusion angle calculation point; Along the arc direction with the diffusion angle calculation point as the radius, determine the two points where the energy on both sides drops to the first energy, and obtain the upper point and the lower point; the first energy is half of the energy at the diffusion angle calculation point; The width of the sound beam in the main direction is determined based on the distance between the upper and lower points; The diffusion angle is calculated based on the width of the sound beam in the main direction and the distance from the origin; the distance from the origin is the distance between the diffusion angle calculation point and the origin; the origin is the position of the ultrasonic transducer.

3. The method for dynamic measurement of transducer acoustic field based on array marker optical imaging according to claim 1, characterized in that, The visualization results obtained from the four-dimensional array specifically include: The four-dimensional array is visualized using pseudo-color encoding, three-dimensional vector field display, or volume rendering methods to generate a three-dimensional dynamic visualization sequence.

4. The method for dynamic measurement of transducer acoustic field based on array marker optical imaging according to claim 1, characterized in that, The acquisition of the vibration image sequence specifically includes: Obtain a sequence of vibration images within a set sound field measurement range; the set sound field measurement range is determined based on the characteristics of the ultrasonic transducer.

5. A transducer acoustic field dynamic measurement device based on array marker optical imaging, characterized in that, include: Ultrasonic excitation module, optical imaging system, synchronous triggering unit, signal processing and reconstruction module; The ultrasonic excitation module is used to drive the ultrasonic transducer to generate ultrasonic waves in the material sample; the surface of the material sample is prepared with an array of equally spaced marker points. The optical imaging system is used to capture a vibration image sequence of the marker array under ultrasonic action; the vibration image sequence includes: a reference frame and time-series image data; The synchronization triggering unit is used to generate a synchronization triggering signal; the synchronization triggering signal is used to synchronously trigger the ultrasonic excitation module and the optical imaging system. The signal processing and reconstruction module is used for: Calculate the planar displacement and out-of-plane displacement of each marker point based on the reference frame and time-series image data; Based on the planar displacement and the out-of-plane displacement, the three-dimensional displacement time series of each marker point is mapped to a regular spatial network to obtain a four-dimensional array; The sound field parameters and visualization results are obtained based on the four-dimensional array.

6. The method for dynamic measurement of transducer acoustic field based on array marker optical imaging according to claim 1, characterized in that, The spacing between the marker points is less than half the wavelength of the ultrasonic wave.

7. The method for dynamic measurement of transducer acoustic field based on array marker optical imaging according to claim 1, characterized in that, The frame rate of the optical imaging system is more than twice the maximum value of the excitation frequency generated by the ultrasonic excitation module, and the image resolution satisfies that each marker point covers 3-5 pixels.

8. A computer device, comprising: A memory, a processor, and a computer program stored in the memory and capable of running on the processor, characterized in that the processor executes the computer program to implement the transducer acoustic field dynamic measurement method based on array marker optical imaging as described in any one of claims 1-4.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, When executed by a processor, the computer program implements the transducer acoustic field dynamic measurement method based on array marker optical imaging as described in any one of claims 1-4.

10. A computer program product, comprising a computer program, characterized in that, When executed by a processor, the computer program implements the transducer acoustic field dynamic measurement method based on array marker optical imaging as described in any one of claims 1-4.

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