A high spatiotemporal resolution elastic guided wave mode detection system

Abstract

This invention discloses a high spatiotemporal resolution elastic guided wave mode detection system, comprising an excitation source, a sample to be tested, a multi-channel fiber optic interferometer, a photoelectric detection module, and a signal recognition and processing module. The excitation source generates ultrasonic waves in the sample to be tested. The multi-channel fiber optic interferometer detects the ultrasonic signals propagating along a specific direction. The photoelectric detection module then converts the optical signals into electrical signals, which are finally processed by the signal recognition and processing module to achieve high-resolution feature detection. This high spatiotemporal resolution elastic guided wave detection system features high measurement accuracy, small error, ease of construction, and wide applicability. It can be applied to underwater sound source localization and non-destructive testing, demonstrating significant application value and promising prospects.

Description

Technical Field

[0001] This invention belongs to the field of laser ultrasonic nondestructive testing technology, specifically relating to an elastic guided wave mode detection system with high spatiotemporal resolution. Background Technology

[0002] In the face of the vast ocean, timely and efficient information transmission is of paramount importance. Due to factors such as high humidity and evaporation in the ocean, optical and wireless communications are severely interfered with. Sound waves, however, propagate rapidly and attenuate minimally in the seabed, making sound wave detection essential for acquiring information from the seabed. Among solid-borne sound waves, elastic waves possess significant advantages such as high propagation speed, low energy loss, and large information capacity, enabling them to effectively modulate information. As the thickness of the metal plate under test gradually increases, the number of modes also increases. Each mode has its corresponding displacement, group velocity, phase velocity, and stress distribution. By observing the fluctuations in sound velocity, we can infer changes in stress and mass at the boundaries. Therefore, this invention has significant scientific research value for studying the propagation modes of surface acoustic waves in solids and underwater solids.

[0003] The rapid development of laser ultrasonic technology is closely related to the rapid improvement of detection technology. Fiber optic sensors are one of the new types of sensor devices, characterized by adjustability, high precision, small size, and wide applicability. They also have low loss and can be used for long-distance detection of complex terrain. In 2007, Liang Yijun's team designed a sensor based on a fiber optic Fizeau interferometer, which can be used to detect displacement caused by surface acoustic wave vibration. In 2010, Ni Chenmeng et al. conducted experiments on the detection of surface cracks in aluminum plates using fully optical excitation and studied and analyzed the transmission characteristics of surface acoustic waves. In 2017, Zhong Yunjie published "Simulation of Laser Ultrasonics for Detection of Surface-Connected Rail Defects" in the "Journal of Nondestructive Evaluation," using a laser ultrasonic detection system to conduct nondestructive testing experiments on cracked rails.

[0004] The above studies all used a single optical path for measurement, which cannot guarantee the high-precision measurement and real-time recording of signal information required for high spatiotemporal resolution elastic guided wave mode detection. Based on the needs of practical development, there is an urgent need to develop a high-precision elastic guided wave mode detection system with high spatiotemporal resolution. Summary of the Invention

[0005] Based on the technical problems existing in the prior art, the present invention provides an elastic guided wave mode detection system with high spatiotemporal resolution. The present invention solves the problem of elastic guided wave mode detection with high spatiotemporal resolution and realizes multi-channel simultaneous measurement of the transmission process of ultrasonic waves in air or underwater in solids.

[0006] Based on the technical solution of this invention, this invention provides an elastic guided wave mode detection system with high spatiotemporal resolution, which includes an excitation source, a sample to be tested, a multi-channel fiber interferometer, a photoelectric detection module, and a signal recognition and processing module. The excitation source excites ultrasonic waves in the sample to be tested, the multi-channel fiber interferometer detects the ultrasonic wave signal transmitted along a specific direction, the photoelectric detection module converts the optical signal into an electrical signal, and finally the signal recognition and processing module processes the signal to achieve high-resolution feature detection.

[0007] Furthermore, the excitation source is non-contact excitation, which uses ultrasonic excitation or pulsed laser source to excite elastic guided wave signals.

[0008] Furthermore, the multi-channel fiber optic interferometer is a multi-channel fiber optic Fizeau interferometer, which simultaneously measures the elastic guided wave signals at different locations on the surface of the sample to be tested.

[0009] The elastic guided wave mode detection system with high spatiotemporal resolution achieves simultaneous detection of elastic wave mode field distribution at different spatial locations by selecting the arrangement of multi-channel fiber optic probes of a multi-channel fiber optic interferometer. The multi-channel fiber optic probes can be arranged in various ways, such as longitudinal, transverse, ring, or T-shaped.

[0010] Preferably, the spatial resolution of different signal detections is controlled by adjusting the channel spacing within the multi-channel fiber optic probe. A multi-core fiber with a core spacing on the order of micrometers is selected as the fiber optic probe for the multi-channel interferometer, thereby achieving ultrasonic signal detection with micrometer-level resolution.

[0011] Furthermore, the photoelectric detection module simultaneously receives multi-channel photoelectric signals. After processing by the signal recognition and processing module, detailed information on the propagation mode, velocity, phase, and intensity distribution in the elastic material can be obtained, and the proportion of different elastic guided wave mode components can be obtained based on the mode analysis algorithm.

[0012] Preferably, the sample to be tested is usually a metal sample, and a four-bearing electric displacement stage is used to drive the metal sample to be tested with an error of less than 0.01 mm.

[0013] Compared with existing technologies, the advantages of the elastic guided wave mode detection system with high spatiotemporal resolution of the present invention are:

[0014] 1. By employing a non-contact excitation method, samples in air (using a solid-state laser) or underwater (using an ultrasonic signal generator) can be excited, which can reduce errors and energy loss.

[0015] 2. The signal is measured using a multi-channel fiber optic interferometry method. The fibers are closely arranged, and the accuracy can reach the micrometer level, solving the problem of low resolution in conventional measurements.

[0016] 3. This system can detect signals at multiple points simultaneously and record the amplitude oscillations at different points at the same time. After processing, it can present a complete pattern distribution at the same time within the scanning area, solving the problem that the waveform will oscillate over time when a single probe measures signals at different points at different times.

[0017] 4. The experimental system can effectively avoid interference from factors such as arm length, is suitable for working in environments with large temperature differences, and has the advantages of high sensitivity, easy adjustment, and high signal-to-noise ratio. It can measure the transmission of elastic waves above and below water, analyze their guided wave modes, and detect the characteristics of the sound source.

[0018] 5. This invention can also be applied to detect defects such as cracks and pores on metal surfaces. It is simple to manufacture and has a wide range of applications. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of an elastic guided wave detection system with high spatiotemporal resolution according to the present invention.

[0020] Figure 2 This is a diagram of the multi-channel fiber optic probe of the elastic guided wave mode detection system with high spatiotemporal resolution of the present invention.

[0021] Figure 3 This is the best-fit curve image for a specific frequency where multiple modes are superimposed. Detailed Implementation

[0022] The accompanying drawings illustrate practical embodiments and technical solutions of the present invention. The described embodiments represent only a portion of the embodiments of the present invention and do not represent all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention. Furthermore, the scope of protection of the present invention should not be limited to the specific parameters of specific modules or parts in the following systems.

[0023] It should be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly or indirectly on that other element. When an element is referred to as being "connected to" another element, it can be directly or indirectly connected to that other element. Unless otherwise specified, the embodiments and features described in the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0024] It should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention.

[0025] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0026] This invention proposes an elastic guided wave mode detection system with high spatiotemporal resolution, which improves the spatiotemporal resolution of the measurement. It uses a detection matrix composed of multiple optical fibers, which can be applied to high-resolution scanning detection, real-time detection and recording of signal information, and has considerable research value in the fields of ultrasonic non-destructive testing technology and seabed acoustic signal source detection.

[0027] The high spatiotemporal resolution elastic guided wave mode detection system of the present invention includes an excitation source, a sample under test, a multi-channel fiber optic interferometer, a photoelectric detection module, and a signal recognition and processing module. The excitation source generates ultrasonic waves in the sample under test. The multi-channel fiber optic interferometer detects the ultrasonic signals propagating along a specific direction. The photoelectric detection module then converts the optical signals into electrical signals, and finally, the signal recognition and processing module processes the signals to achieve high-resolution feature detection. The high spatiotemporal resolution elastic guided wave mode detection system of the present invention includes an excitation source capable of accurately detecting minute vibrations on the sample surface and detecting elastic waves propagating along the surface of the sample under test. The detected vibration magnitude can reach the micrometer level.

[0028] The excitation source uses a non-contact excitation method, which includes two scenarios: The first scenario involves measuring the transmission of underwater ultrasonic signals through a solid. An ultrasonic signal generator is used to excite the sample underwater to generate an ultrasonic signal. The excitation and receiving ends of the ultrasonic probe are located on opposite sides of the metal sample. The synchronization signal port of the ultrasonic signal generator is connected to the corresponding port on the oscilloscope as a synchronization signal. The second scenario involves measuring the transmission of ultrasonic signals in air through a solid. A pulsed laser source is used to excite the sample to generate an ultrasonic signal. The laser emitted by the laser source is split into two parts by a plane lens. One part of the light passes through the plane lens and is focused onto the surface of the sample by a convex lens to generate ultrasonic waves. The other part of the light reflected by the plane lens is converted into an electrical signal by a photoelectric detection module and then transmitted to the oscilloscope as a synchronization signal.

[0029] The sample to be tested is usually a metal sample. A four-bearing electric displacement stage is used to drive the metal sample to be tested, with an error of less than 0.01 mm.

[0030] The multi-channel fiber optic interferometer employs a multi-channel fiber optic Fizeau interferometer to measure ultrasonic waves at different points within the sample. Preferably, the multi-channel fiber optic probes of the multi-channel interferometer can be arranged according to the sample surface size and actual needs. Adapting to the arrangement direction of the multi-channel fibers, the probes can be selectively fabricated in longitudinal, transverse, ring, or T-shaped arrangements, allowing for high-resolution detection of the ultrasonic field distribution at different locations on the sample. In another embodiment, multi-core fibers with a core spacing on the order of micrometers can be used as the multi-channel fiber optic probes of the multi-channel fiber optic interferometer. An optical support is used to fine-tune the fiber optic probes, with each fiber end face having a diameter of 125 μm, achieving micrometer-level resolution ultrasonic signal detection. This enables high-precision, high spatiotemporal resolution detection of elastic waves propagating along the plate thickness direction.

[0031] The photoelectric detection module consists of multiple photodetectors and can simultaneously convert multiple optical signals into electrical signals.

[0032] The signal recognition and processing module includes an oscilloscope with a high sampling rate and high vertical resolution, as well as a high-pass or low-pass filter module. It uses signal processing algorithms to process the measured signal and analyze changes in phase difference and delay. After processing by the signal recognition and processing module, information such as propagation modes, velocity, phase, and intensity distribution details in the elastic material can be obtained. Based on mode analysis algorithms, the proportion of different elastic guided wave modes can be obtained.

[0033] Working principle of an elastic guided wave mode detection system with high spatiotemporal resolution:

[0034] The elastic guided wave mode detection system with high spatiotemporal resolution utilizes a laser to radiate onto the surface of the sample to be tested. (1) For solid materials, based on the principle of thermoelastic effect, the excited laser generates ultrasonic waves such as Lamb waves, Rayleigh waves, longitudinal waves, and transverse waves in the metal. (2) For underwater samples, an ultrasonic signal generator is used to excite ultrasonic signals in the underwater sample. Based on the optical interference method, the measurement light and the laser reflected from the surface of the sample to be tested generate an alternating bright and dark interference signal. By appropriately adjusting the optical resonant cavity, a light intensity output proportional to the vibration signal can be obtained. The interferometer built is a multi-channel fiber optic Fizeau interferometer, which can simultaneously measure ultrasonic waves at different points in the sample to be tested. The signal recognition and processing module is used to identify the ultrasonic waves transmitted along the side of the sample and to perform corresponding frequency band filtering based on the actual excited ultrasonic wave frequency band. The MATLAB program is used to analyze the ultrasonic waves in the time and frequency domains. After processing and calculation, information such as the propagation speed, phase, and intensity distribution of ultrasonic waves in the material can be obtained, thereby obtaining the high spatiotemporal resolution feature detection of the elastic guided wave.

[0035] Compared to existing technologies, this invention enables high-resolution detection. Its working principle lies in the fact that the fiber optic probes of the multi-channel interferometer can be arranged in various ways, including longitudinal, transverse, circular, and T-shaped arrangements, etc., according to actual needs. This allows for high-resolution detection of the ultrasonic field distribution at different locations on the sample. The spacing between different channels in the multi-channel fiber optic probe can be adjusted as needed, and multi-core fibers with a core spacing on the order of micrometers can also be used as the interferometer's fiber optic probes to achieve micrometer-level resolution ultrasonic signal detection.

[0036] The waveform transmitted in the sample under test is a standing wave. Although the nodes and frequency do not change at different times, they oscillate over time. This invention, a high spatiotemporal resolution elastic guided wave mode detection system, effectively solves this problem by using a densely arranged multi-channel fiber optic probe to simultaneously measure ultrasonic signals at different points within the sample. The spatiotemporal resolution is further enhanced by adjusting the optical path design and detection method, improving the efficiency of the photoelectric converter, and increasing the number of sampling times during detection.

[0037] When ultrasonic signals propagate through solids, they generate symmetrical and antisymmetric modes of different orders and reflection numbers. By applying equal-sized, perpendicular loads about the neutral plane along the plate thickness, symmetrical or antisymmetric modes such as S0, A0, S1, A1, etc., can be measured. Depending on the excitation conditions or the introduced structure, different mode variations will occur in the sample under test, and under specific conditions, mode superposition may occur.

[0038] The elastic guided wave mode detection system of this invention, with high spatiotemporal resolution, can determine the main mode distribution and mode change law in signal transmission by processing and analyzing the measured ultrasonic signal. Systematic analysis of this system can help explore the specific location of underwater sound sources and solve problems such as ultrasonic non-destructive testing.

[0039] The present invention will be further described below with reference to the accompanying drawings and preferred embodiments. Figure 1 As shown, Figure 1 This diagram illustrates an elastic guided wave detection system with high spatiotemporal resolution. When measuring underwater ultrasonic signals transmitted through solids, an underwater ultrasonic excitation module is used. An ultrasonic signal generator, via an underwater ultrasonic probe, excites ultrasonic waves on the surface of the sample. When measuring airborne ultrasonic signals transmitted through solids, an airborne ultrasonic excitation module is used. A pulsed laser source radiates laser light; a portion of the light is reflected by a plane lens as reference light, then passes through a photodetector and connects to the corresponding synchronization signal port of the oscilloscope. The other portion of the light passes through the plane lens and is focused onto the surface of the sample by a convex lens to excite ultrasonic waves. A narrow-linewidth laser is selected as the measurement light source. Its radiated laser light is split into multiple paths by a beam splitter. Each path is connected to a fabricated fiber optic probe via a circulator, forming a multi-channel fiber optic interferometer. The output signal is received by multiple photodetectors, forming a photodetector module that converts the optical signal into an electrical signal. The signal is then acquired by a multi-channel oscilloscope and processed using a signal recognition and processing module composed of a high-pass (low-pass) filter processor and algorithms programmed in MATLAB.

[0040] Furthermore, this invention employs an underwater ultrasonic signal generator to excite ultrasonic waves. A semi-submerged aluminum plate, measuring 6mm × 120mm × 200mm, is selected as the test sample. A four-bearing precision electric displacement stage is used to fix or clamp the aluminum plate, adjusting it along the z-axis to ensure it is semi-submerged. An ultrasonic signal generator is used to generate an ultrasonic signal underwater, with the ultrasonic probe fully submerged and 6mm from the lower edge of the aluminum plate. The selected ultrasonic signal generator has a frequency range of 0.25MHz-20MHz and a pulse voltage range of 100V-400V. The frequency is adjusted to 1MHz, the voltage to 400V, and the gain to -49dB. A seven-channel fiber optic interferometer is used for detection. The detection light source emitted by a narrow-linewidth laser is split into seven beams by a beam splitter, each connected to a circulator to ensure the light travels along a specific path. Each circulator is connected at one end to a fiber optic probe fixed on a flange and adjustable via a fiber optic adjustment bracket. The fiber optic probes are arranged in a seven-core ring configuration, with a seven-core fan-in / fan-out design. The probes are fixed on a fiber optic adjustment bracket that allows for three-dimensional adjustment. The output signal is received by a photodetector, which converts the interference light signal generated by the optical path difference between the detection light passing through the fiber end face and the surface of the aluminum plate sample into an electrical signal, which is then output to a multi-channel signal recognition and processing module for processing.

[0041] A MATLAB program was used to filter the measured signal and perform a Fourier transform to analyze its frequency domain. An ultrasonic probe was used to receive the time-domain signal of the excited elastic wave. It was observed that the elastic wave time-domain signal measured by the fiber optic probe exhibited significant phase differences in its horizontal arrangement and significant delay differences in its vertical arrangement. The frequency domain signal obtained after the Fourier transform was largely consistent with the frequency domain of the excitation signal. The ultrasonic frequency excited by the probe was approximately 1 MHz, and the measured signal, after frequency domain analysis, showed a significant amplitude around 1 MHz.

[0042] It should be further explained that in a simple thin-plate waveguide made of aluminum, both symmetrical and antisymmetrical waveguide modes can coexist, and the proportion of each mode varies depending on the excitation conditions. By analyzing the measured signal in both the time and frequency domains, the sound velocity can be calculated, and then the distribution of different waveguide modes can be analyzed.

[0043] In this embodiment, high-resolution detection is achieved by using a densely arranged multi-fiber optic probe to simultaneously measure ultrasonic waves at different points within the sample (aluminum plate), adjusting the optical path design and detection method, and improving the efficiency of the photoelectric converter and the number of sampling times.

[0044] The above description represents a preferred application of the present invention, but the scope of protection of the present invention is not limited thereto. The number of fiber optic probes is not limited to seven; more channel fiber optic probes are also within the scope of protection of the present invention. Any modifications or substitutions easily conceived by researchers skilled in the art within the scope of the technology disclosed in this invention should fall within the scope of protection of this invention.

[0045] In another embodiment, when measuring the transmission of underwater ultrasonic signals in a solid, an underwater ultrasonic excitation module is used. An ultrasonic signal generator uses an underwater ultrasonic probe to excite ultrasonic waves on the surface of the sample under test. When measuring the transmission of airborne ultrasonic signals in a solid, an airborne ultrasonic excitation module is used. A pulsed laser source radiates laser light; part of the light is reflected by a plane lens as reference light and then connected to the corresponding synchronization signal port of the oscilloscope via a photodetector. The other part of the light passes through the plane lens and is focused onto the surface of the sample under test by a convex lens to excite ultrasonic waves. A narrow-linewidth laser is selected as the measurement light source. Its radiated laser light is split into multiple paths by a beam splitter. Each path is connected to a fabricated fiber optic probe via a circulator, forming a multi-channel fiber optic interferometer. The output signal is received by multiple photodetectors, forming a photodetector module that converts the optical signal into an electrical signal. The signal is then acquired by a multi-channel oscilloscope, and processed by a signal recognition and processing module composed of a high-pass (low-pass) filter processor and computer algorithms such as MATLAB.

[0046] like Figure 2 The diagram shows a multi-channel fiber optic probe. Ultrasonic waves are excited on the surface of the sample, and the probe is used for scanning and measurement. The spacing between different channels in the multi-channel fiber optic probe can be adjusted according to actual needs. Alternatively, multi-core fibers with a core spacing on the order of micrometers can be selected as interferometer fiber optic probes to achieve ultrasonic signal detection with micrometer-level resolution. The probe core arrangement can be designed as a ring arrangement (①), a longitudinal arrangement (②), a transverse arrangement (③), a T-shaped arrangement (④), etc. The arrangement can be customized according to actual needs to achieve high-resolution detection of the ultrasonic field distribution at different locations on the sample.

[0047] Figure 3 This is the best-fit curve image for multiple modes superimposed at a specific frequency. The electric field along the y-axis near the sample inlet is fitted, and the system is used to detect the mode distribution and analyze the multi-mode transmission. The fitting algorithm shows that the A0 and S1 modes account for a relatively large proportion.

[0048] Compared with existing technologies, this invention designs and fabricates an elastic guided wave detection system with high spatiotemporal resolution, capable of simultaneously measuring and calculating high spatiotemporal resolution elastic guided wave mode information using multiple fiber optic probes. The advantages of this invention are: employing a non-contact excitation method to excite samples in air (using a solid-state laser in air) or underwater (using an ultrasonic signal generator in underwater), reducing errors and energy loss; and using a multi-channel fiber optic interferometry method to measure signals, with tightly arranged fibers, achieving micrometer-level accuracy, thus solving the problem of low resolution in conventional measurements. This invention presents a high spatiotemporal resolution elastic guided wave detection system capable of simultaneously detecting signals at multiple points, recording the amplitude oscillations at different points at the same time. After processing, the system displays a complete pattern distribution within the scanning area at the same moment, solving the problem of waveform oscillations caused by a single probe measuring signals at different points at different times. Furthermore, this system effectively avoids interference from factors such as arm length, is suitable for operation in environments with large temperature differences, and boasts advantages such as high sensitivity, ease of adjustment, and a high signal-to-noise ratio. It can measure the transmission of elastic waves above and below water, analyze their guided wave modes, and detect the characteristics of the sound source. This system can also be applied to detect defects such as cracks and pores on metal surfaces, is simple to manufacture, and has a wide range of applications.

[0049] The above description is merely a specific embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the working principle and structural composition of the present invention should be included within the protection scope of the present invention.

Claims

1. An elastic guided-wave mode detection system with high spatial and temporal resolution, characterized by, It includes an excitation source, a sample to be tested, a multi-channel fiber interferometer, a photoelectric detection module, and a signal recognition and processing module. The excitation source generates ultrasonic waves in the sample to be tested, the multi-channel fiber interferometer detects the ultrasonic signals transmitted along a specific direction, the photoelectric detection module converts the optical signals into electrical signals, and finally the signal recognition and processing module processes the signals to achieve high-resolution feature detection. The multi-channel fiber optic interferometer is a multi-channel fiber optic Fizeau interferometer used to simultaneously measure elastic guided wave signals at different locations on the surface of the sample under test. A narrow linewidth laser is selected as the measurement light source. The radiation laser from the measurement light source is split into multiple beams by a beam splitter. Each beam is connected to a fabricated fiber optic probe through a circulator to form a multi-channel fiber optic interferometer. The output signal is received by multiple photodetectors to form a photodetector module, which converts the optical signal into an electrical signal. By selecting the arrangement of the multi-channel fiber optic probes of a multi-channel fiber optic interferometer, the simultaneous detection of elastic wave mode field distributions at different spatial locations can be achieved. The multi-channel fiber optic probes of the multi-channel fiber optic interferometer can be arranged in longitudinal, transverse, ring, or T-shaped configurations. The spatial resolution of different signal detections can be controlled by adjusting the channel spacing within the multi-channel fiber optic probe. Multi-core optical fibers with a core spacing on the order of micrometers are selected as the fiber optic probes of the multi-channel interferometer to achieve ultrasonic signal detection with micrometer-level resolution.

2. The elastic guided-wave mode detection system with high spatial and temporal resolution of claim 1, wherein, The excitation source uses a non-contact excitation method, which employs ultrasonic excitation or pulsed laser source to excite elastic guided wave signals.

3. The elastic guided-wave mode detection system with high spatial and temporal resolution of claim 1, wherein, The photoelectric detection module simultaneously receives photoelectric signals from multiple channels.

4. A high spatiotemporal resolution elastic guided wave mode detection system according to claim 1 or claim 3, characterized in that, After processing by the signal recognition and processing module, detailed information on the propagation mode, velocity, phase, and intensity distribution in the elastic material can be obtained, and the proportion of different elastic guided wave mode components can be obtained based on the mode analysis algorithm.

5. The elastic guided-wave mode detection system with high spatial and temporal resolution of claim 1 or claim 3, wherein, The sample to be tested is a metal sample. A four-bearing electric displacement stage is used to drive the metal sample, with an error of less than 0.01 mm.

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