Quantum detection system, magnetic flux leakage detection equipment and detection method

Abstract

The present invention relates to the field of quantum lossless sensing technology, and the scheme is a quantum detection system, a magnetic flux leakage detection device and a detection method, which include a first detection area, a narrow field sensing probe, a second detection area, a wide field imaging probe, a laser unit, a microwave unit, a fluorescence acquisition unit and a data processing module; the present invention can quickly discover and locate surface defects of an object to be detected through the designed narrow field sensing probe, and then accurately image the discovered defects through the wide field imaging probe. The system greatly reduces the difficulty of fluorescence data processing, makes defect measurement more efficient and accurate, and can meet a variety of detection needs.

Description

Technical Field

[0001] The present invention relates to the field of quantum lossless sensing technology, and in particular to a quantum detection system, magnetic flux leakage detection equipment and a detection method. 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. 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 proposes a quantum detection system, a magnetic flux leakage detection device and a detection method 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 quantum detection system, comprising:

[0008] The first detection area;

[0009] A narrow field sensing probe, configured to perform sensing detection on the first detection area, comprising a plurality of detection positions distributed at intervals, wherein the detection positions comprise diamond grains containing NV color centers;

[0010] A second detection area, which is spaced apart from the first detection area in front and behind;

[0011] A wide-field imaging probe, configured to perform sensing detection on the second detection area, comprising a substrate containing NV color centers and an objective lens placed therewith;

[0012] a laser unit, configured to transmit a first excitation light to the narrow field sensing probe and / or transmit a second excitation light to the wide field imaging probe, wherein the first excitation light is used to excite the diamond grains to generate a first fluorescent signal, and the second excitation light is used to excite the substrate to generate a second fluorescent signal;

[0013] a microwave unit configured to transmit a first microwave signal to the narrow field sensing probe and / or transmit a second microwave signal to the wide field imaging probe;

[0014] A fluorescence collection unit, configured to collect the first fluorescence signal and / or collect the second fluorescence signal through an objective lens;

[0015] Data processing module, used for signal conditioning, data processing and system control.

[0016] In a further embodiment, the narrow field sensing probe comprises diamond grains containing NV color centers arranged in a row, and sensing areas of adjacent diamond grains overlap.

[0017] In a further solution, each diamond grain is independently configured with an optical fiber and bonded to the middle of one end face of the optical fiber. The side of all optical fibers away from the diamond grain is converged into an input light path through a beam combiner. The first excitation light enters the beam combiner through the input light path and is evenly divided and transmitted to each diamond grain.

[0018] In a further embodiment, the lengths of the optical fibers connected to the diamond particles are different, and the first excitation light is configured as pulsed light.

[0019] In a further embodiment, the substrate is a light-transmitting medium, and the substrate comprises a first surface and a second surface that are opposite to each other, the second surface is arranged toward the objective lens, and NV color centers are evenly distributed on the first surface.

[0020] In a further embodiment, the substrate is a sheet of diamond containing NV color centers as a whole.

[0021] In a further solution, a driving unit is also included, and the driving unit is used to control the position movement of the wide-field imaging probe and the narrow-field sensing probe.

[0022] In a further embodiment, the fluorescence collection unit includes a photodiode and a wide-field camera, the photodiode is configured to collect a first fluorescence signal, and the wide-field camera is configured to collect a second fluorescence signal.

[0023] On the other hand, the present invention also provides a magnetic flux leakage detection device, which applies the quantum detection system as described above and further includes a magnetizer, wherein the magnetizer is configured to magnetize the object to be tested so as to generate a magnetic flux leakage field at the surface defects of the object.

[0024] On the other hand, the present invention also provides a defect detection method, which applies the detection system as described above, first calibrates the defect position using a narrow-field sensing probe, then uses a wide-field imaging probe to perceive the calibrated defect as a whole and captures the image through a fluorescence acquisition unit.

[0025] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention can quickly detect and locate surface defects of the object to be tested through the designed narrow-field sensing probe, and then accurately image the discovered defects through the wide-field imaging probe. The system greatly reduces the difficulty of fluorescence data processing, making defect measurement more efficient and accurate, and can meet a variety of detection needs. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] 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.

[0027] Figure 1 is a system block diagram of the quantum detection system in Example 1;

[0028] Figure 2 is a schematic diagram of the narrow field sensing probe in Example 1;

[0029] Figure 3 Schematic diagram of the structure of the substrate containing NV color center in Example 1;

[0030] Figure 4 is a structural schematic diagram of the laser unit in Example 1;

[0031] Figure 5 is another structural schematic diagram of the laser unit in Example 1;

[0032] Figure 6 It is a schematic diagram of the microwave radiation structure adapted for two probes in Example 1;

[0033] Figure 7 is a schematic diagram of an area comparison between the first detection area and the second detection area in Example 1;

[0034] Figure 8 Another schematic diagram of area comparison between the first detection area and the second detection area in Example 1;

[0035] Fig. 9 This is a schematic diagram of the combination of the magnetizer and the two probes in Example 2;

[0036] Fig.10 is a schematic structural diagram of the magnetizer in Example 2;

[0037] Fig.11 This is a flow chart of the defect detection method in Example 3. DETAILED DESCRIPTION

[0038] 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.

[0039] <Example 1>

[0040] See attached Figure 1 This embodiment provides a quantum detection system, including a first detection area 1, a narrow field sensing probe 2, a second detection area 3, a wide field imaging probe 4, a laser unit 5, a microwave unit 6, a fluorescence collection unit 7 and a data processing module 8.

[0041] The first detection area 1 is a virtual area corresponding to the narrow field sensing probe 2 , and the first detection area 1 refers to a collection of sensing areas of the diamond grains 21 containing NV color centers.

[0042] In this example, the narrow field sensing probe 2 is configured to perform sensing detection on the first detection area 1, which includes a plurality of detection positions distributed at intervals, and the detection positions include diamond particles 21 containing NV color centers. In an exemplary solution, as shown in the attached Figure 2 As shown, the narrow field sensing probe 2 includes diamond grains 21 containing NV color centers arranged in a row, and the sensing areas (light-colored circular areas in the figure) of adjacent diamond grains 21 overlap. In a preferred embodiment, each diamond grain 21 is independently configured with an optical fiber 22 and bonded to the middle of one end face of the optical fiber 22. The side of all optical fibers 22 away from the diamond grain 21 is converged into an input light path through a beam combiner 23. The first excitation light enters the beam combiner 23 through the input light path and is evenly divided and transmitted to each diamond grain 21. Further, in order to accurately know the defect The point is located in the first detection area. In some schemes, the aforementioned structure is also optimized. One of the schemes is to set the lengths of the optical fibers 22 to be different from each other, and configure the first excitation light to be in the form of pulsed light. Due to the different total lengths of the optical paths, the fluorescence signals generated by different diamond grains 21 are obtained at different times. Based on this difference, the detection signal generated by each diamond grain 21 can be distinguished, and then the abnormal value can be bound to the position of the diamond grain 21, so that the exact position of the defect in the first detection area can be obtained.

[0043] In this example, the second detection area 3 is also a virtual area (corresponding to the sensing area of ​​the wide-field imaging probe 4), which is spaced apart from the first detection area 1 in front and behind. Compared with the first detection area 1, the second detection area 3 has a wider area to facilitate the acquisition of specific detection images of the defect point and its surroundings.

[0044] In this example, the wide-field imaging probe 4 is configured to perform sensing detection on the second detection area 3, and includes a substrate 41 containing NV color centers and an objective lens 42 placed therewith. In this example, the purpose of the wide-field imaging probe 4 is to obtain defect imaging information, so the substrate 41 is required to have a larger detection area, such as 3cm*3cm. In some schemes, the substrate 41 can be a sheet of diamond containing NV color centers as a whole, which has better measurement results, but the manufacturing difficulty and cost of large-sized diamonds are relatively high. Therefore, as some preferred alternatives, such as the attached Figure 3 As shown, the substrate 41 is a light-transmitting medium (such as silicon dioxide, etc.), and the substrate 41 includes a first surface and a second surface that are opposite to each other. The second surface is arranged toward the objective lens, and NV color centers (which can be nano-scale diamond powder containing NV color centers) are evenly distributed on the first surface. This structural design can reduce manufacturing costs and can easily obtain a larger detection area.

[0045] In this example, the laser unit 5 is configured to transmit a first excitation light to the narrow-field sensing probe 2 and / or a second excitation light to the wide-field imaging probe 4, wherein the first excitation light is used to excite the diamond grains 21 to generate a first fluorescence signal, and the second excitation light is used to excite the substrate 41 to generate a second fluorescence signal. In an exemplary scheme, an optical path switching device 50 may also be provided on the light output side of the laser unit 5 to selectively pass the required light as needed.

[0046] In addition, it should be known that the first excitation light and the second excitation light should be different, and the second excitation light should be a wide field light that can fully excite the substrate 4. To meet this goal, in the exemplary solution, as shown in the attached Figure 4 As shown, the laser unit 5 includes a wide-field light source 51 and a beam laser 52. The wide-field light source 51 is used to emit the second excitation light, and the beam laser 52 is used to emit the first excitation light. This dual-light source design has the ability to open and close the light path, so there is no need to configure an optical path opening and closing device. In other solutions, such as the attached Figure 5 As shown, the laser unit 5 has only one beam laser 52, and a one-to-two optical splitter 53 is connected on its output side to divide the laser beam into two paths. One path is expanded by a beam expansion lens group 54 to become a wide-field light (i.e., the second excitation light), and the other path acts on the narrow-field sensor probe 2 (i.e., the first excitation light). In this case, since the laser is in a normally-on state, it is suitable to be configured with an optical path switching device for use.

[0047] In this example, the microwave unit 6 is configured to transmit a first microwave signal to the narrow field sensing probe 2 and / or transmit a second microwave signal to the wide field imaging probe 4. In an exemplary solution, a microwave switching device 60 may be connected to the output side of the microwave unit 6 to form two microwave signals to work separately. Regarding the microwave radiation structure, in an exemplary solution, as shown in the attached Figure 6 As shown, corresponding to the substrate 41, the microwave radiation structure can be a copper strip 62 arranged on the side of the substrate 41, and corresponding to the narrow field sensing probe 2, the microwave radiation structure can be a copper wire 61 including a plurality of spiral structures, and each diamond grain 21 is located inside a spiral structure. Of course, these are only some example structural designs of the microwave radiation structure.

[0048] In this example, the fluorescence collection unit 7 is configured to collect the first fluorescence signal and / or collect the second fluorescence signal through the objective lens. This solution not only realizes the rapid inspection and imaging of defects, but also meets some separate detection requirements. For example, when there is no need for detection imaging, only the first fluorescence signal needs to be collected. It can also meet the needs of continuous imaging detection, when only the second fluorescence signal needs to be collected. In some example solutions, such as the attached Figure 1 The fluorescence collection unit 7 includes a first light collector 71 for collecting a first fluorescence signal, a second light collector 72 for collecting a second fluorescence signal, and two groups of lens combinations arranged on the input side of the collector, the lens combination includes a dichroic plate 70 and a filter 73. When working, the first excitation light passes through the dichroic plate 70 to enter the narrow field sensing probe 2, and excites the diamond particles 21 to generate a first fluorescence signal. The first fluorescence signal returns along the original path, is reflected by the same dichroic plate 70, and is filtered by a filter 73 before being received by the first light collector 71. Similarly, the second excitation light passes through another dichroic plate 70 to enter the wide field imaging probe 4, and excites it to generate a second fluorescence signal. The second fluorescence signal returns along the original path, is reflected by the same dichroic plate 70, and is filtered by a filter 73 before being received by the second light collector 72. Preferably, the first light collector 71 is a photodiode (such as an avalanche diode, etc.), and the second light collector 72 is a wide field camera (such as a CCD, CMOS, etc.).

[0049] In this example, the data processing module 8 is used for signal conditioning, data processing and system control. Conventionally, the data processing module 8 is a device with corresponding capabilities, such as a computer and an FPGA.

[0050] In some schemes, such as Figure 7 As shown, the length of the first detection area is much greater than the length of the second detection area, or as shown in the attached Figure 8As shown, the lengths of the two are close. Corresponding to the former solution, when actually switching detection (switching from narrow-field detection to wide-field imaging detection), it is necessary to move the second detection area longitudinally to achieve sufficient coverage detection. Corresponding to the latter solution, it is also necessary to move the second detection area laterally to achieve an accurate measurement position. Therefore, the preferred solution also includes a driving unit for controlling the position movement of the wide-field imaging probe and the narrow-field sensing probe.

[0051] <Example 2>

[0052] This embodiment is further improved on the basis of the embodiment 1, and proposes a magnetic flux leakage detection device. Specifically, as shown in the attached Fig. 9 As shown, a magnetizer 9 is added, which is configured to magnetize the object to be tested so as to generate a leakage magnetic field at the surface defects of the object to be tested. The narrow field sensing probe 2 and the wide field imaging probe 4 are both located at positions where the leakage magnetic field can be detected. In the exemplary scheme, as shown in the attached Fig.10 As shown, the magnetizer 9 includes an iron core and two magnets, wherein the main body of the iron core is a U-shaped block, the two ends of the U-shaped block are bent downward to form two curved legs (and each curved surface is a smooth arc surface), and a slot is provided on the bottom surface of the curved leg, and the magnet is installed in the slot, and the polarities of the left and right magnets are set oppositely.

[0053] Of course, in some solutions, the aforementioned magnet may also be connected to an energized coil to generate the required magnetizing magnetic field.

[0054] <Example 3>

[0055] This example corresponds to the quantum detection system of Example 1, and proposes a defect detection method, specifically:

[0056] S1. First, use the narrow field sensor probe to calibrate the defect position.

[0057] In a specific example, the first fluorescence signal generated by the narrow field sensor probe can be obtained based on a photodiode. For this case, two situations are discussed here:

[0058] First, the photodiode does not distinguish the fluorescence signals sent back by the diamond particles containing NV color centers at each detection point. At this time, the photodiode collects all the fluorescence signals uniformly and generates an electrical signal. The data processing module compares the electrical signal with the pre-stored monitoring threshold. If the value exceeds the threshold, an instruction is issued to switch the working mode.

[0059] Secondly, the photodiode can distinguish the fluorescence signals transmitted back by the diamond particles containing NV color centers at each detection point. At this time, it will generate corresponding multiple electrical signals (in pulse form, see the previous text for details). The data processing module compares each electrical signal with the pre-stored monitoring threshold (of course, the mode of comparing the extreme value or average value can also be adopted). If the value is exceeded, an instruction is issued to switch the working mode.

[0060] S2. Use the wide-field imaging probe to perceive the calibrated defects as a whole and take images through the fluorescence acquisition unit.

[0061] In some inspection situations, such as continuous mobile inspection of the inspection surface (non-handheld movement), after the defect position is found based on the narrow-field sensor probe, due to reaction time or other settings, the equipment often moves a certain distance. At this time, it is necessary to move it to the exact defect point position for detection based on the wide-field imaging probe. Therefore, before executing S2, the wide-field imaging probe needs to be moved back to the marked defect point. The principle and structure used in the mobile reset process are relatively common and will not be repeated here.

[0062] In addition, in some other detection situations, there are often continuous defects in a longer area. If the defect detection device switches to the S2 step at the starting point of the defect, a more complete measurement effect cannot be obtained. Therefore, in some detection schemes, it is also required to include issuing a change instruction when the following conditions are met, that is, after it is found that the electrical signal exceeds the monitoring threshold, and then the change instruction is issued when the electrical signal recovers to be lower than the monitoring threshold. 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, the S2 step 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).

[0063] 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.

[0064] 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 quantum detection system, characterized in that: Include: The first detection area; A narrow field sensing probe, configured to perform sensing detection on the first detection area, comprising a plurality of detection positions distributed at intervals, wherein the detection positions comprise diamond grains containing NV color centers; A second detection area, which is spaced apart from the first detection area in front and behind; A wide-field imaging probe, configured to perform sensing detection on the second detection area, comprising a substrate containing NV color centers and an objective lens placed therewith; a laser unit, configured to transmit a first excitation light to the narrow field sensing probe and / or transmit a second excitation light to the wide field imaging probe, wherein the first excitation light is used to excite the diamond grains to generate a first fluorescent signal, and the second excitation light is used to excite the substrate to generate a second fluorescent signal; a microwave unit configured to transmit a first microwave signal to the narrow field sensing probe and / or transmit a second microwave signal to the wide field imaging probe; A fluorescence collection unit, configured to collect the first fluorescence signal and / or collect the second fluorescence signal through an objective lens; Data processing module, used for signal conditioning, data processing and system control.

2. A quantum detection system according to claim 1, characterized in that: The narrow field sensing probe comprises diamond grains containing NV color centers arranged in a row, and sensing areas of adjacent diamond grains overlap.

3. A quantum detection system according to claim 2, characterized in that: Each diamond particle is independently configured with an optical fiber and bonded to the middle of one end face of the optical fiber. The side of all optical fibers away from the diamond particles is converged into an input light path through a beam combiner. The first excitation light enters the beam combiner through the input light path and is evenly divided and transmitted to each diamond particle.

4. A quantum detection system according to claim 3, characterized in that: The lengths of the optical fibers connected to the diamond grains are different, and the first excitation light is configured as pulse light.

5. A quantum detection system according to claim 1, characterized in that: The substrate is a light-transmitting medium, and includes a first surface and a second surface that are opposite to each other, the second surface is arranged toward the objective lens, and NV color centers are evenly distributed on the first surface.

6. A quantum detection system according to claim 1, characterized in that: The substrate is a sheet-like diamond containing NV color centers as a whole.

7. A quantum detection system according to claim 1, characterized in that: The device also comprises a driving unit, which is used to control the position movement of the wide-field imaging probe and the narrow-field sensing probe.

8. A quantum detection system according to claim 1, characterized in that: The fluorescence collection unit includes a photodiode and a wide-field camera. The photodiode is configured to collect a first fluorescence signal, and the wide-field camera is configured to collect a second fluorescence signal.

9. A magnetic flux leakage detection device, using the quantum detection system according to any one of claims 1 to 8, characterized in that: The device also comprises a magnetizer, which is configured to magnetize the object to be tested so as to generate leakage magnetic field at the surface defects of the object.

10. A defect detection method, using the quantum detection system according to any one of claims 1 to 8, characterized in that: First, the defect position is calibrated using a narrow-field sensing probe, and then the calibrated defect is perceived as a whole using a wide-field imaging probe and imaged using a fluorescence acquisition unit.

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