Nondestructive testing method and nondestructive testing device

Abstract

The present invention relates to the field of quantum nondestructive sensing technology, and the scheme includes a nondestructive testing method and a nondestructive testing device, wherein the nondestructive testing device comprises a fluorescence signal acquisition module, an electrical signal acquisition module, a signal processing module and a signal judgment module; the present invention combines a diamond NV color center that can generate a wide-field fluorescence signal with a wide-field camera for sensing detection, and is configured with an electrical signal acquisition module, a signal processing module and a signal judgment module, and quickly locates the defect position through a normalized electrical signal, and can automatically switch working modes, and realizes two-dimensional imaging of the position after the defect position is determined, realizes coverage detection, and can obtain more accurate defect morphology.

Description

Technical Field

[0001] The present invention relates to the field of quantum nondestructive sensing technology, and in particular to a nondestructive testing method and a nondestructive testing device. Background Art

[0002] Magnetic flux leakage detection has always been an important research direction in the field of non-destructive testing. Magnetic flux leakage detection equipment using traditional magnetic sensors has been relatively complete, and its functions have their own advantages and disadvantages. This application is based on the research of quantum precision measurement, a new detection technology, and plans to make new breakthroughs in the field of magnetic flux leakage non-destructive testing based on quantum sensing. In recent years, the research on solid-state spin color center systems in the field of quantum precision has developed rapidly, especially for the detection of magnetic fields. A detection method based on optical detection magnetic resonance (ODMR) has been developed. By studying the linear relationship between the magnetic resonance frequency and the external magnetic field, the precise measurement of the external magnetic field can be achieved.

[0003] For example, the Chinese invention patent with authorization announcement number CN117705932B proposes a quantum nondestructive sensor and a rail surface defect detection machine, which utilizes diamond NV color centers to realize nondestructive detection of ferromagnetic materials. It can accurately detect the leakage magnetic field on a single path, but at present, the volume of single-crystal diamond NV color centers is generally at the micron level, and the measurement coverage area is small, which is not conducive to rapid and comprehensive detection of wide fields. Although the combination of some existing large-size diamond NV color centers and wide-field cameras can solve the comprehensive detection function of wide fields, in actual detection, it will generate a large amount of useless data, resulting in a large amount of back-end data calculation and storage, and greatly affecting the measurement efficiency.

[0004] The present invention is designed based on this problem and proposes a corresponding solution. Summary of the invention

[0005] The present invention provides a nondestructive testing method and a nondestructive testing device to solve the problems existing in the prior art.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] A non-destructive testing method comprising:

[0008] Acquire a wide-field fluorescence signal generated by detecting the surface of the object to be tested using a diamond NV color center sensor unit;

[0009] Using a wide-field camera to collect the wide-field fluorescence signal and form a detection electrical signal;

[0010] The detection electrical signal is received and data processing is performed based on the following two modes:

[0011] Mode 1: In the absence of a change instruction, the detected electrical signal is averaged or maximized to obtain a quick-check electrical signal;

[0012] Mode 2: In the case of a change instruction, a two-dimensional defect map is generated based on the difference in the detected electrical signals of each pixel point;

[0013] Receive and determine whether the quick-check electrical signal exceeds the detection threshold. If not, no change instruction is issued; if so, a change instruction is issued and the defect point location is marked.

[0014] A further solution also includes moving the diamond NV color center sensing unit back to the marked defect point when executing mode two.

[0015] A further solution also includes issuing a change instruction when the following conditions are met, that is, issuing a change instruction after it is found that the quick-check electrical signal exceeds the detection threshold, and then when the quick-check electrical signal recovers to be lower than the detection threshold.

[0016] In a further embodiment, the size of the signal observation area of ​​the wide-field camera when there is no change instruction is smaller than the size of the signal observation area when there is a change instruction.

[0017] On the other hand, the present invention also provides a nondestructive testing device, comprising:

[0018] A fluorescence signal acquisition module, used to acquire a wide-field fluorescence signal generated by detecting the surface of the object to be tested using a diamond NV color center sensor unit;

[0019] An electrical signal acquisition module, used to collect the wide-field fluorescence signal using a wide-field camera and form a detection electrical signal;

[0020] The signal processing module is used to receive the detection electrical signal and perform data processing based on the following two modes:

[0021] Mode 1: In the absence of a change instruction, the detected electrical signal is averaged or taken to the extreme value to obtain a quick-check electrical signal;

[0022] Mode 2: In the case of a change instruction, a two-dimensional defect map is generated based on the difference in the detected electrical signals of each pixel point;

[0023] The signal judgment module is used to receive and judge whether the quick-check electrical signal exceeds the detection threshold. If not, no change instruction is issued; if so, a change instruction is issued and the defect point position is marked.

[0024] A further solution also includes a position fine-tuning module, which is used to move the diamond NV color center sensor unit back to the marked defect point when executing mode two.

[0025] In a further solution, the signal judgment module further includes a command trigger unit, which issues a change instruction when the following conditions are met, that is, after it is found that the quick-check electrical signal exceeds the detection threshold, and then when the quick-check electrical signal first recovers to be below the detection threshold, a change instruction is issued.

[0026] In a further solution, an observation adjustment module is also included, which is used to automatically adjust the size of the observation area of ​​the wide-field camera, and the trigger medium for the automatic adjustment is a change instruction.

[0027] In a further embodiment, the diamond NV color center sensing unit comprises:

[0028] A substrate containing NV color centers is used to generate wide-field fluorescence signals under the illumination of excitation light;

[0029] an objective lens, located above the substrate and used for magnifying the substrate;

[0030] The microwave antenna is located on the peripheral side or the lower side of the substrate and is used for receiving microwave signals and radiating microwave fields to the substrate.

[0031] A further solution also includes a laser module for generating excitation light and a microwave module for generating microwave signals.

[0032] A further solution also includes a spectrometer disposed above the objective lens, wherein the spectrometer is configured to: direct the excitation light introduced from one side into the objective lens and then illuminate the substrate to generate a wide-field fluorescence signal, and to direct the wide-field fluorescence signal that returns to the substrate along the original light path from the other side.

[0033] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention combines the diamond NV color center that can generate a wide-field fluorescence signal with a wide-field camera for sensing detection, and is configured with an electrical signal acquisition module, a signal processing module and a signal judgment module. The defect position is quickly located through a normalized electrical signal, and the working mode can be automatically switched. Once the defect position is determined, two-dimensional imaging of the position is achieved, and coverage detection is realized, so that more accurate defect morphology can be obtained. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for describing the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0035] Figure 1 is a system block diagram of the nondestructive testing device in Example 1;

[0036] Figure 2is a schematic diagram of the fluorescence signal acquisition module in Example 1;

[0037] Figure 3 Schematic diagram of the structure of the diamond NV color center sensing unit in Example 1;

[0038] Figure 4 Schematic diagram of the structure of the substrate containing NV color center in Example 1;

[0039] Figure 5 This is a flow chart of the nondestructive testing method in Example 2. DETAILED DESCRIPTION

[0040] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0041] <Example 1>

[0042] See attached Figure 1 This embodiment provides a nondestructive testing device, which includes a fluorescence signal acquisition module, an electrical signal acquisition module, a signal processing module and a signal judgment module.

[0043] In this example, the fluorescence signal acquisition module is used to acquire the wide-field fluorescence signal generated by detecting the surface of the object to be tested using the diamond NV color center sensor unit; to achieve the generation of the wide-field fluorescence signal, the NV color center in the diamond NV color center sensor unit should be distributed in a relatively large range. In the exemplary scheme, it is preferred to use large-sized flake diamonds containing NV color centers, and other structures can also be used (further description will be made later). Considering that a lot of stray light is generated along with the wide-field fluorescence signal, in the preferred scheme, the fluorescence signal acquisition module should also include filtering devices (such as filters, dichroic filters, etc.) ), these stray lights are filtered out; of course, it should be known that the fluorescence signal acquisition module should also include basic components that promote the formation of wide-field fluorescence signals, such as a laser module for generating excitation light, a microwave module for generating microwave signals, etc. In this example, corresponding to the diamond NV color center, a green laser with a wavelength of 532nm can be used as the excitation laser, and the diamond NV color center can generate 637nm red fluorescence under its irradiation. In a specific example, the laser module includes a 532nm laser and can also include an optical modulator, by which the excitation laser can be modulated to obtain a better detection effect.

[0044] For ease of understanding, an exemplary scheme introduces the composition of a fluorescence signal acquisition module, specifically, as shown in the attached Figure 2 As shown, it includes a diamond NV color center sensor unit 1, a laser module 2, a microwave module 3, a wide-field camera 4, a filter 5 and a host 6. When working, the laser module 2 emits an excitation laser, and the microwave module 3 emits a microwave signal. The excitation laser and the microwave signal finally act on the diamond NV color center sensor unit 1, forcing it to generate a wide-field fluorescence signal. The wide-field fluorescence signal is filtered and removed by the filter 5 and then processed by the wide-field camera 4. The host 6 processes and analyzes the data sent back by the wide-field camera 4. As a possible preferred structure, as shown in the attached figure, Figure 3 As shown, the diamond NV color center sensing unit 1 includes a substrate 11 containing NV color centers, which is used to generate a wide-field fluorescence signal under the irradiation of excitation light; an objective lens 12, which is located above the substrate 11 and is used to amplify the substrate 11; a microwave antenna 13, which is located on the peripheral side or the lower side of the substrate 11 and is used to receive microwave signals and radiate microwave fields to the substrate 11; further, it also includes a spectrometer 14 (dual-color plate) arranged above the objective lens 12, and the spectrometer 14 is configured to: introduce the excitation laser introduced from one side into the objective lens 12 and then irradiate the substrate 11 to generate a wide-field fluorescence signal, and export the wide-field fluorescence signal that returns to the incident itself along the original light path from the other side. As for the substrate 11, it can be a sheet-like diamond block, but considering the difficulty in making large-sized diamond blocks and the high price, in other schemes, such as the attached Figure 4 As shown, the substrate 11 is a block of a transparent material (such as silicon dioxide, etc.), which includes a first surface and a second surface relative to each other, the second surface faces the objective lens 12, and the first surface is evenly distributed with diamond powder (nano or micron level) containing NV color centers. This structural design has a lower cost and also meets basic measurement requirements.

[0045] In this example, the electrical signal acquisition module is used to collect the wide-field fluorescence signal using a wide-field camera and form a detection electrical signal; a conventional wide-field camera has the ability to convert light signals into electrical signals, but it will perform further conversion and ultimately present graphic imaging information. This solution requires the use of electrical signals before they are converted into graphic imaging information, and thus defines an electrical signal acquisition module, the detection electrical signal output by which retains the fluorescence intensity and position information of each detection point.

[0046] In this example, the signal processing module is used to receive the detection electrical signal and perform data processing based on the following two modes:

[0047] Mode 1: In the absence of a change instruction, the detected electrical signal is averaged or taken to the extreme value to obtain a quick-check electrical signal;

[0048] Regarding mode one, its main purpose is to achieve rapid discovery of defects and their locations. This process does not require individual analysis of the fluorescence generated by all diamond NV color centers. It only needs to know whether there are outliers. Therefore, for the detection of electrical signals, the average value or the extreme value can be used for processing. This algorithm greatly reduces the workload of the back-end processing equipment and can effectively shorten the detection time of defects and their locations.

[0049] Mode 2: In the case of a change instruction, a two-dimensional defect map is generated based on the difference in the detected electrical signals of each pixel point;

[0050] Regarding mode 2, its purpose is to obtain the accurate morphology of the defect, so it is necessary to independently analyze the batch of wide-field fluorescence signals and finally form a two-dimensional defect map. This process is basically consistent with the function of a conventional wide-field camera and will not be repeated here. In the preferred solution, the wide-field camera can be a CCD camera or a CMOS camera.

[0051] In this example, the signal judgment module is used to receive and determine whether the quick-check electrical signal exceeds the detection threshold. If not, no change instruction is issued; if so, a change instruction is issued and the defect point location is marked. Regarding the signal judgment module, it is a conventional data comparison module, in which the detection threshold is collected in some early simulation tests, and the specific size depends on the detection requirements.

[0052] In some inspection situations, such as continuous mobile inspection of the inspection surface (non-handheld movement), after the defect position is found based on mode 1, due to reaction time or other settings, the diamond NV color center sensor unit often moves a certain distance. At this time, it is necessary to move it to the exact defect point position for mode 2 detection. Therefore, the further solution also includes a position fine-tuning module ( Figure 1 The light-colored part in the middle), which is used to move the diamond NV color center sensor unit back to the marked defect point when executing Mode 2. The moving distance can be determined in the previous simulation experiment and will not be repeated here. If the non-destructive testing device is to maintain continuous automatic testing, it is necessary to move the diamond NV color center sensor unit to reset (the position before position fine-tuning) through the position fine-tuning module after Mode 2 is completed, and continue to detect in Mode 1 from the reset point.

[0053] In some inspection situations, there are often continuous defects in a longer area. If the defect detection device switches to mode two at the starting point of the defect, a relatively complete measurement effect cannot be obtained. Therefore, in a further scheme, the signal judgment module also includes a command trigger unit, which issues a change instruction when the following conditions are met, that is, after it is found that the quick-check electrical signal exceeds the detection threshold, the change instruction is issued when the quick-check electrical signal recovers to be lower than the detection threshold for the first time. The purpose is to facilitate the determination of the extension length of the defect point and know the starting and end points of the defect. At this time, mode two is used to complete the coverage detection of the entire defect (if the defect area is too long, the image of the entire defect area can be obtained by splicing shooting).

[0054] For mode one, since it is not necessary to analyze the fluorescence signal of each point, in order to further reduce the working intensity of the instrument, it can be set to acquire the local wide-field fluorescence signal. Therefore, in a further scheme, it also includes an observation adjustment module, which is used to automatically adjust the size of the observation area of ​​the wide-field camera. The trigger medium for its automatic adjustment is the change instruction. Specifically, the observation adjustment module can be a ROI (region of interest) control module. Different from the traditional ROI control module, this scheme needs to bind it with the change instruction. After the initial setting is completed, the wide-field fluorescence signal collects the wide-field fluorescence signal of the set area. When an abnormal value is found and a change instruction is issued, the ROI control module should be able to switch to fluorescence collection of a larger area according to the change instruction.

[0055] <Example 2>

[0056] As attached Figure 5 As shown, embodiment 2 corresponds to the nondestructive testing device of embodiment 1, and proposes a nondestructive testing method, comprising:

[0057] S1. Obtain a wide-field fluorescence signal generated by detecting the surface of the object to be tested using a diamond NV color center sensor unit; in a specific example, in order to generate a wide-field fluorescence signal, a large-area distributed NV color center should be used, which generates a red wide-field fluorescence signal under the action of a microwave field and a 532nm laser.

[0058] S2. Use a wide-field camera to collect the wide-field fluorescence signal and form a detection electrical signal. In a specific example, an objective lens should be arranged between the wide-field camera and the diamond NV color center sensor unit, and the wide-field fluorescence signal is collected by photographing with the wide-field camera. In this step, the wide-field camera does not need to output an image, but only needs to obtain the electrical signal before it is converted into graphic imaging information.

[0059] S3, receiving the detection electrical signal, and performing data processing based on the following two modes:

[0060] Mode 1: In the absence of a change instruction, the detected electrical signal is averaged or maximized to obtain a quick-check electrical signal; in mode 2, for the detected electrical signal obtained in step S2, there is no need to perform a separate analysis based on the electrical signal obtained from each pixel point, and the average value or extreme value can be used for processing. This algorithm greatly reduces the workload of the back-end processing equipment and can effectively shorten the detection time of defects and their locations.

[0061] Mode 2: In the case of a change instruction, a two-dimensional defect map is generated based on the difference in the detected electrical signals of each pixel point; its purpose is to obtain the accurate morphology of the defect, so it is necessary to independently analyze the wide-field fluorescence signals of a batch and finally form a two-dimensional defect map. This process is basically the same as the function of a conventional wide-field camera and will not be repeated here.

[0062] S4, receiving and judging whether the quick-check electrical signal exceeds the detection threshold, if not, no change instruction is issued; if yes, a change instruction is issued and the defect point location is marked; regarding the signal judgment module, it is a conventional data comparison module, in which the detection threshold is collected in some early simulation tests, and the specific size is determined according to the detection requirements.

[0063] In some inspection situations, such as continuous mobile inspection of the inspection surface (non-handheld movement), after the defect position is found based on mode one, due to reaction time or other settings, the diamond NV color center sensor unit often moves a certain distance. At this time, it is necessary to move it to the exact defect point position for mode two detection. Therefore, when executing mode two, it is also necessary to move the diamond NV color center sensor unit back to the marked defect point. The principles and structures used in the mobile reset process are relatively common and will not be repeated here.

[0064] In some inspection situations, there are often continuous defects in a relatively long area. If the defect detection device switches to Mode 2 at the starting point of the defect, a relatively complete measurement effect cannot be obtained. Therefore, in some inspection schemes, it is also required to include issuing a change instruction when the following conditions are met, that is, after the quick-check electrical signal is found to exceed the detection threshold, a change instruction is issued until the quick-check electrical signal recovers to be lower than the detection threshold. The purpose is to facilitate the determination of the extension length of the defect point and know the starting and ending points of the defect. At this time, Mode 2 is used to complete the coverage detection of the entire defect (if the defect area is too long, the image of the entire defect area can be obtained by splicing shooting).

[0065] For mode 1, since it is not necessary to analyze the fluorescence signal of each point, in order to further reduce the working intensity of the instrument, it can be set to acquire the local wide-field fluorescence signal. Therefore, in a further scheme, the signal observation area size of the wide-field camera when there is no change instruction can be required to be smaller than the signal observation area size when there is a change instruction; specifically, the observation adjustment module can be a ROI (region of interest) control module. Different from the traditional ROI control module, this scheme needs to bind it with the change instruction. After the initial setting is completed, the wide-field fluorescence signal collects the wide-field fluorescence signal of the set area. When an abnormal value is found and a change instruction is issued, the ROI control module should be able to switch to fluorescence collection of a larger area according to the change instruction.

[0066] In the description of this specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0067] The preferred embodiments of the present invention disclosed above are only used to help explain the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to only specific implementation methods. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A nondestructive testing method, characterized in that: Include: Acquire a wide-field fluorescence signal generated by detecting the surface of the object to be tested using a diamond NV color center sensor unit; Using a wide-field camera to collect the wide-field fluorescence signal and form a detection electrical signal; The detection electrical signal is received and data processing is performed based on the following two modes: Mode 1: In the absence of a change instruction, the detected electrical signal is averaged or maximized to obtain a quick-check electrical signal; Mode 2: In the case of a change instruction, a two-dimensional defect map is generated based on the difference in the detected electrical signals of each pixel point; Receive and determine whether the quick-check electrical signal exceeds the detection threshold. If not, no change instruction is issued; if yes, a change instruction is issued and the defect point location is marked; For continuous defects in a long area, a change instruction is issued when the following conditions are met, that is, a change instruction is issued after the quick-check electrical signal is found to exceed the detection threshold, and then when the quick-check electrical signal recovers to be lower than the detection threshold.

2. The nondestructive testing method according to claim 1, characterized in that: The method also includes moving and restoring the diamond NV color center sensing unit to the marked defect point when executing mode two.

3. The nondestructive testing method according to claim 1, characterized in that: The signal observation area size of the wide-field camera when there is no change command is smaller than the signal observation area size when there is a change command.

4. A nondestructive testing device, characterized in that: Include: A fluorescence signal acquisition module, used to acquire a wide-field fluorescence signal generated by detecting the surface of the object to be tested using a diamond NV color center sensor unit; An electrical signal acquisition module, used to collect the wide-field fluorescence signal using a wide-field camera and form a detection electrical signal; The signal processing module is used to receive the detection electrical signal and perform data processing based on the following two modes: Mode 1: In the absence of a change instruction, the detected electrical signal is averaged or taken to the extreme value to obtain a quick-check electrical signal; Mode 2: In the case of a change instruction, a two-dimensional defect map is generated based on the difference in the detected electrical signals of each pixel point; The signal judgment module is used to receive and judge whether the quick-check electrical signal exceeds the detection threshold. If not, no change instruction is issued; if so, a change instruction is issued and the defect point location is marked; the signal judgment module also includes a command trigger unit. For continuous defects in a long area, a change instruction is issued when the following conditions are met, that is, after it is found that the quick-check electrical signal exceeds the detection threshold, a change instruction is issued when the quick-check electrical signal recovers to be below the detection threshold for the first time.

5. The nondestructive testing device according to claim 4, characterized in that: It also includes a position fine-tuning module, which is used to move the diamond NV color center sensing unit back to the marked defect point when executing mode two.

6. The nondestructive testing device according to claim 4, characterized in that: It also includes an observation adjustment module, which is used to automatically adjust the size of the observation area of ​​the wide-field camera, and the trigger medium for the automatic adjustment is a change instruction.

7. The nondestructive testing device according to claim 4, characterized in that: The diamond NV color center sensing unit comprises: A substrate containing NV color centers is used to generate wide-field fluorescence signals under the illumination of excitation light; an objective lens, located above the substrate and used for magnifying the substrate; The microwave antenna is located on the peripheral side or the lower side of the substrate and is used for receiving microwave signals and radiating microwave fields to the substrate.

8. The nondestructive testing device according to claim 7, characterized in that: It also includes a laser module for generating excitation light and a microwave module for generating microwave signals.

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