Magnetic detection device

Abstract

The utility model provides a magnetic detection device which comprises a light source which is configured to emit detection light, and the detection light is polarized light at least at a preset position where the detection light enters a detected object; the detector is configured to at least receive the detection light reflected by the detected object, and the detector detects the magneto-optical effect at the preset position according to the received detection light; the magnetic field generating device comprises a magnetic field generating coil and a pulse power supply device for providing current for the magnetic field generating coil, and the magnetic field generating coil is constructed to be in a form of at least forming a magnetic field environment at the preset position, so that the test requirement in the high-speed changing magnetic field environment can be met; the magnetic field at the preset position is easy to adjust and is convenient to control.

Description

Technical Field

[0001] The utility model belongs to the technical field of measuring magnetic variables, relates to measuring by using magneto-optical effect, and specifically relates to a magnetic detection device. Background Art

[0002] The magneto-optical Kerr effect means that reflected light will change due to the magnetization of the reflective medium. Therefore, the magnetism of the object under test can be obtained by detecting the reflected light on the surface of the object under test. On this basis, the magneto-optical Kerr detection equipment measures the polarization state of the reflected light of the object under test by emitting polarized light to the object under test, thereby measuring the magnetism of the surface of the object under test.

[0003] In some cases, it is necessary to place the object under test in a magnetic field environment so that the magnetism of the object under test changes under the influence of the magnetic field environment, and use a magneto-optical Kerr detection device to detect the magnetic changes of the object under test, so as to analyze the magnetic properties of the object under test. In the prior art, a magnetic field is usually generated by using an electromagnet, and the pole head of the electromagnet is brought close to the object under test so that the object under test is placed in a controllable magnetic field environment. However, since the pole head material in the electromagnet is prone to generate induced current during operation, thereby partially offsetting the excitation effect, the speed at which the electromagnet generates a magnetic field is usually slow, and cannot meet the test requirements in a high-speed changing magnetic field environment. In some cases, the speed of change of the magnetic field can be increased by removing the pole head or the magnetic core, but this method greatly reduces the magnetic field strength of the generated magnetic field environment and cannot meet the test requirements in a large magnetic field environment.

[0004] Therefore, it is difficult to simultaneously meet the requirements of high-speed change and high magnetic field strength in existing magnetic field generation schemes.

[0005] The above information disclosed in the background technology section is only used to enhance the understanding of the background of the present invention and therefore may contain information that does not constitute the prior art known to ordinary technicians in this field. Utility Model Content

[0006] In order to provide a device capable of performing magnetic detection of an object to be measured in a magnetic field environment with high-speed changes and high magnetic field strength, the utility model provides a magnetic detection device, comprising: a light source, which is configured to emit detection light, and the detection light is polarized light at least at a preset position of the incident object to be measured; a detector, which is configured to at least receive the detection light reflected by the object to be measured, and the detector detects the magneto-optical effect at the preset position based on the received detection light; a magnetic field generating device, comprising a magnetic field generating coil and a pulse power supply device for providing current to the magnetic field generating coil, and the magnetic field generating coil is constructed in a form capable of forming a magnetic field environment at least at the preset position.

[0007] According to one embodiment of the present utility model, the pulse power supply device is a capacitor pulse power supply device.

[0008] According to one embodiment of the utility model, the magnetic detection device also includes a signal acquisition device, which is communicatively connected to the magnetic field generating device and the detector, and is constructed to be able to synchronously acquire the current of the magnetic field generating coil and the signal of the detector.

[0009] According to one embodiment of the present utility model, the magneto-optical effect detection component includes the light source and the detector, and two magneto-optical effect detection components are respectively arranged on both sides of the object to be detected.

[0010] According to one embodiment of the present utility model, at least one magnetic field generating coil is respectively disposed on both sides of the object to be measured.

[0011] According to one embodiment of the present invention, the detection light passes through the magnetic field generating coil and enters the object to be measured.

[0012] According to one embodiment of the present utility model, the magnetic field generating coils disposed on both sides of the object to be measured are connected to the same pulse power supply device.

[0013] According to one embodiment of the present utility model, the two magnetic field generating coils are symmetrically arranged on both sides of the object to be measured.

[0014] According to one embodiment of the present utility model, the light source includes a light emitting device and a polarizer, and the light emitted by the light emitting device passes through the polarizer and serves as the detection light.

[0015] According to one embodiment of the present utility model, the detector includes a polarizer and a photodetector, and the detection light reflected by the object to be detected enters the photodetector after passing through the polarizer.

[0016] According to one embodiment of the present utility model, the detector includes a Wollaston prism and two photoelectric detectors. After the detection light reflected by the object to be detected passes through the Wollaston prism, it enters the two photoelectric detectors respectively.

[0017] According to one embodiment of the present utility model, the axis of the magnetic field generating coil is perpendicular to the surface of the object to be measured.

[0018] According to one embodiment of the present utility model, the power supply device is a pulse power supply device.

[0019] According to one embodiment of the present utility model, the detection light is incident on the preset position along a direction perpendicular to the object to be measured; the magnetic detection device also includes a spectroscope, the detection light emitted by the light source is incident on the preset position via the spectroscope, and the detection light reflected by the object to be measured is incident on the detector via the spectroscope.

[0020] According to one embodiment of the present utility model, the detection light is incident on the preset position at an angle.

[0021] According to one embodiment of the present utility model, the magnetic detection device further includes a stage, and the stage is configured to support the object to be detected.

[0022] According to one embodiment of the present utility model, the stage can at least drive the object to be measured to move in a direction parallel to the plane where the surface of the object to be measured is located.

[0023] The utility model has at least the following beneficial effects: the utility model provides a magnetic detection device, which uses a magnetic field generating coil without a pole head or a magnetic core to generate a magnetic field, which can avoid the influence of the hysteresis and residual magnetism of the pole head or the magnetic core on the speed of change of the magnetic field, and greatly improve the speed of change of the magnetic field; the preset position to be tested of the object to be tested is located in the magnetic field environment of the magnetic field generating coil to meet the testing requirements in a high-speed changing magnetic field environment, and the magnetic field at the preset position is easy to adjust, which greatly facilitates the control of the magnetic field and the use of the detection equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the overall structure of an implementation method of a magnetic detection device.

[0025] Figure 2 It is a schematic diagram of the overall structure of another embodiment of the magnetic detection device.

[0026] Figure 3 It is a schematic diagram of the overall structure of another embodiment of the magnetic detection device.

[0027] Figure 4 It is a schematic diagram of the overall structure of another embodiment of the magnetic detection device.

[0028] Figure 5 It is a schematic diagram of the relationship between the preset position involved in the magnetic detection device and the magnetic field generating coil.

[0029] Figure 6 It is a schematic diagram of the overall structure of another embodiment of the magnetic detection device.

[0030] Figure 7 It is a schematic diagram of the overall structure of another embodiment of the magnetic detection device. DETAILED DESCRIPTION

[0031] In order to make the purpose and features of the utility model more obvious and easy to understand, the specific implementation methods of the utility model are further described below in conjunction with the accompanying drawings. It should be noted that the accompanying drawings are all in a very simplified form and use inaccurate ratios, which are only used to conveniently and clearly assist in explaining the embodiments of the utility model.

[0032] The utility model provides a magnetic detection device, including: a light source 100, which is configured to emit a detection light L, and the detection light L is polarized light at least at a preset position F incident on the object to be measured 400. Specifically, a polarizer or a polarizer can be inserted into the path of the light emitted by the light source, or polarized light can be obtained in the form of reflection or refraction, or a birefringent crystal or lens can be inserted into the path of the light emitted by the light source, or a dichroic mirror can be inserted into the path of the light emitted by the light source, etc., to obtain polarized light. For the specific method of obtaining polarized light, those skilled in the art can select it according to actual needs, and it will not be repeated here.

[0033] The detection light L needs to be polarized light when it enters the preset position F of the object to be measured 400. There is no limitation on where in the optical path the detection light L meets the requirement of polarized light. For example, the polarized light can be formed in the light source 100 or in the propagation process of the detection light L. To be more specific, the corresponding lens or optical device that makes the detection light L have the characteristics of polarized light only needs to be arranged in the optical path before the detection light L enters the preset position F of the object to be measured 400.

[0034] The detection light L is polarized light, which mainly means that the detection light L can be roughly regarded as linearly polarized light to obtain a better magneto-optical effect detection effect.

[0035] The detector 200 is configured to at least receive the detection light L reflected by the object 400. The detector 200 detects the magneto-optical effect at the preset position F according to the received detection light L. The detector 200 can output corresponding data or signals according to the needs and the difference in actual configuration. The detector 200 is at least in a form that can detect the polarization state or polarization direction of the detection light L. As a more common form, the detector 200 may include an analyzer 210 and a photodetector 220. The polarization direction of the detection light L is converted into light intensity information by the analyzer 210, and then the light intensity information is analyzed by the photodetector 220 to analyze the magneto-optical effect at the preset position F. In addition, a combination of a Wollaston prism 230 and two photodetectors 221 and 222 can also be used. The detection light L reflected by the object 400 is divided into two orthogonal polarized lights by the Wollaston prism 230, and enters the photodetectors 221 and 222 respectively. The magneto-optical effect at the preset position F is analyzed by jointly analyzing the signals of the two photodetectors 221 and 222.

[0036] The magnetic field generating device 300 includes a magnetic field generating coil 310 and a pulse power supply device 320 for providing current to the magnetic field generating coil 310. The magnetic field generating coil 310 is configured to form a magnetic field environment at least at a preset position F. The pulse power supply device 320 provides current to the magnetic field generating coil 310 for generating a magnetic field environment.

[0037] Through the above-mentioned settings, the magnetic field is generated by the magnetic field generating coil 310 without a pole head or a magnetic core, which can avoid the influence of the hysteresis and residual magnetism of the pole head or the magnetic core on the speed of change of the magnetic field, greatly improve the speed of change of the magnetic field, and make the preset position F of the object to be tested 400 located in the magnetic field environment of the magnetic field generating coil 310, so as to meet the test requirements in the magnetic field environment with high-speed changes; the pulse power supply device 320 is used to provide current to the magnetic field generating coil 310, which can provide at least instantaneous large current to the magnetic field generating coil 310, so as to further enhance the magnetic field strength generated by the magnetic field generating coil 310. By using this solution, a large magnetic field with high-speed changes can be obtained, which can meet the detection requirements of high-speed large magnetic fields.

[0038] In some cases, as needed, a corresponding magnetic core can be set near the magnetic field generating coil 310 to at least enhance the strength of the magnetic field, and by adjusting the size, shape, material, state and other characteristics of the magnetic core, the influence of the magnetic core on the changing speed of the magnetic field at the preset position F can be reduced to meet the corresponding detection requirements.

[0039] For the measured position of the measured object 400, i.e., the preset position F, the relative position of the preset position F and the magnetic field generating coil 310 can be set to clarify the magnetic field at the preset position F of the measured object 400 and ensure that the magnetic field at the preset position F meets the detection requirements. Specifically, the preset position F is set within the range of the projection S1 of the inner ring 311 of the magnetic field generating coil 310. Please refer to Figure 5 , shows a specific position setting method, wherein the magnetic field generating coil 310 can be annular, including a hollow inner ring. The inner ring of the magnetic field generating coil 310 forms a projection range S1 on the surface 410 of the object 400 to be measured, and the preset position F is located within the projection range S1.

[0040] The preset position F is located within the projection range S1, and the corresponding preset position F can be arbitrarily selected within the projection range S1 as the detection position. As a better implementation method, the preset position F can be located near the intersection of the axis of the magnetic field generating coil 310 and the surface 401 of the object 400 to make the magnetic field at the preset position F easier to control and calculate.

[0041] In addition, since the preset position F is located within the range of the projection S1 of the inner ring 311 of the magnetic field generating coil 310, the uniformity of the magnetic field within this range is relatively good, which can ensure that the magnetic field environment of the preset position F meets the detection requirements, and it is easy to adjust the magnetic field of the preset position F, which greatly facilitates the control of the magnetic field and the use of the detection equipment. In addition, the inner ring of the magnetic field generating coil 310 can be used for the optical path of the detection light L, which can simplify the optical path structure of the equipment and reduce the equipment cost.

[0042] It should be noted that the cross section of the magnetic field generating coil 310 is circular, square or any other shape, which can determine the range of the projection S1 . For example, the range of the projection S1 is determined by the minimum cross section of the inner ring 311 .

[0043] As an optional implementation, the pulse power supply device 320 can be selected as needed, for example, it can be a capacitor pulse power supply device, an inductor pulse power supply device, or a mechanical energy pulse power supply device. As a better implementation, a capacitor pulse power supply device can be used.

[0044] In some cases, a signal acquisition device can be further provided on the basis of the technical solution provided by the utility model, and the signal acquisition device is communicatively connected with the magnetic field generating device and the detector, and the signal acquisition device is constructed to synchronously acquire the current of the magnetic field generating coil 310 and the signal of the detector 200. According to the current of the magnetic field generating coil 310, the magnetic field of the magnetic field generating coil 310 can be calculated, and then the magnetic field at the preset position F of the measured object 400 can be obtained; according to the signal of the detector 200, the intensity of the magneto-optical effect at the preset position F can be obtained, and then the magnetism at the preset position F can be obtained; according to the magnetic field and the magnetic data at the preset position F, the magnetic properties of the measured object can be analyzed.

[0045] In some cases, both sides of the object 400 to be tested need to be magnetically detected. Accordingly, the light source 100 and the detector 200 can be used as magneto-optical effect detection components, and at least one magneto-optical effect detection component is respectively arranged on both sides of the object 400 to be tested, so as to realize double-sided detection of the object 400 to be tested. Figure 6 , shows a specific implementation method with two magneto-optical effect detection components, wherein the first light source 100 and the first detector 200 are used as the first magneto-optical effect detection component and are arranged on the left side of the object to be measured 400; the second light source 100' and the second detector 200' are used as the second magneto-optical effect detection component and are arranged on the right side of the object to be measured 400. The two magneto-optical effect detection components can detect the magnetism on both sides of the object to be measured respectively.

[0046] When detecting the magnetism of the two sides of the object 400 to be tested, in some cases, one magnetic field generating coil 310 is sufficient to make the magnetic field environment at the preset position F on both sides of the object 400 to be tested meet the detection requirements; in other cases, one magnetic field generating coil 310 is difficult to make the magnetic field environment at the preset position F on both sides of the object 400 to be tested meet the detection requirements. At least one magnetic field generating coil 310 can be set on both sides of the object 400 as needed. Of course, the required number of magnetic field generating coils 310 can also be set on both sides of the object 400 as needed. Please refer to Figure 6 , shows a specific implementation, wherein the magnetic field generating coil 310 is disposed on the left side of the object under test 400, and the magnetic field generating coil 310' is disposed on the right side of the object under test 400.

[0047] In some cases, in order to further make the magnetic field environments of the preset positions F on both sides of the object 400 to be measured the same, the two magnetic field generating coils 310 and 310 ′ may be symmetrically arranged on both sides of the object 400 to be measured.

[0048] In some cases, the performance or structure of the magnetic field generating coils 310, 310' are the same; the performance or structure of the magnetic field generating coils 310, 310' can also be different; and according to the detection requirements, the position relationship between the coils 310, 310' and the object under test 400 is configured to configure the magnetic field environment in which the object under test 400 is located.

[0049] When two magnetic field generating coils 310 and 310' are provided, in some cases, it is necessary to make the two magnetic field generating coils 310 and 310' generate magnetic fields substantially at the same time. Figure 6 The magnetic field generating coils 310 and 310' disposed on both sides of the object 400 can be connected to the same pulse power supply device 320, see Figure 7 Or the magnetic field generating coils 310, 310' arranged on both sides of the object under test 400 can be connected to different pulse power supply devices 320, 320' and the pulse power supply devices 320, 320' are synchronously controlled so that the currents of the two magnetic field generating coils 310, 310' are roughly synchronized.

[0050] As a more feasible solution, please refer to Figures 1 to 4 The light source 100 includes a light emitting device 110 and a polarizer 120. The light emitted by the light emitting device 110 has a corresponding polarization state after passing through the polarizer 120, and can be used as the detection light L to be incident on a preset position F of the object to be measured 400. For the light emitting device 110, a laser light source, a light emitting diode light source, or other devices capable of generating light can be selected as the light emitting device 110.

[0051] See also Figure 1 , 34. The detector 200 may include a polarizer 210 and a photodetector 220. The detection light L reflected by the object 400 enters the photodetector 220 after passing through the polarizer 210. The corresponding magneto-optical effect is analyzed according to the signal of the photodetector 220, especially the light intensity signal.

[0052] See also Figure 2 , shows another scheme of the detector 200, wherein the detector 200 may include a Wollaston prism 230 and two photodetectors 221 and 222. The detection light L reflected by the object 400 passes through the Wollaston prism 230 and enters the two photodetectors 221 and 222 respectively, and calculations are performed between the two photodetectors 221 and 222, for example, the signals of the two photodetectors 221 and 222 are subtracted to analyze the corresponding magneto-optical effect.

[0053] See also Figure 5 As an embodiment with better effect, the axis of the magnetic field generating coil 310 is perpendicular to the surface 410 of the object 400 to form a magnetic field substantially perpendicular to the surface 410 of the object 400 in at least a part of the surface 410 of the object 400. In this case, a relatively uniform magnetic field substantially perpendicular to the surface 410 of the object 400 can be formed within the range of the projection S1 of the inner ring 311 of the magnetic field generating coil 310.

[0054] In order to further increase the speed of change of the magnetic field generated by the magnetic field generating coil 310, the pulse power supply device 320 can be either a single pulse or a multi-pulse, and the specific output waveform is not limited here.

[0055] See also Figure 1 , 2 , the detection light L can be incident on the preset position F along a direction perpendicular to the object 400 to at least detect the polar magneto-optical Kerr effect at the preset position F. At this time, a spectroscope 600 can usually be set in the optical path, and the detection light L emitted by the light source 100 is incident on the preset position F through the spectroscope 600, and the detection light L reflected by the object 400 is incident on the detector 200 through the spectroscope 600. As a feasible method, please refer to Figure 5 In this case, at least the magnetism of the object 400 in the vertical direction can be detected by the detector 200 .

[0056] See also Figure 3 , Figure 4 , the detection light L can also be incident on the preset position F at an angle. Specifically, the detection light L can pass through the inner ring 311 of the magnetic field generating coil 310, and the direction of the detection light L forms an angle with the vertical direction of the surface 401 of the object 400. As a feasible method, please refer to Figure 5The specific path of the detection light L2 in the object 400. In this case, the angle at which the detection light L is incident on the object 400 can be adjusted to detect the magnetism in the in-plane direction and the vertical direction of the object 400. Generally, a smaller incident angle can be used to mainly analyze the magnetism in the vertical direction at the preset position F of the object 400, or a larger incident angle can be used to mainly analyze the magnetism in the vertical direction and in-plane direction at the preset position F of the object 400.

[0057] See also Figures 1 to 5 The magnetic detection device provided by the utility model further includes a stage 500, which is configured to support the object 400. Specifically, the stage 500 can provide an area on which the object 400 is placed, and can also further provide a fixing effect on the object 400. The specific form of the stage 500, in addition to the platform form for carrying the object 400, can also be a fixed structure, a displacement structure, etc. for grabbing or fixing the object 400, which can be selected according to needs.

[0058] In some cases, the object to be measured 400 needs to be moved to adjust the detected position as needed. Accordingly, the stage 500 can drive the object to be measured 400 to move in some cases. More specifically, the stage 500 can at least drive the object to be measured 400 to move in a plane parallel to the surface 401 of the object to be measured.

[0059] The above shows and describes the basic principles, main features and advantages of the utility model, so the above is only an embodiment of the utility model. The technicians in this industry should understand that the utility model is not limited by the above embodiments, and the above embodiments and descriptions only describe the principles of the utility model. Without departing from the spirit and scope of the utility model, the utility model also includes various equivalent changes and improvements, which will fall within the scope of the utility model to be protected.

Claims

1. A magnetic detection device, characterized in that: include: A light source configured to emit detection light, wherein the detection light is polarized light at least at a preset position where the detection light is incident on the object to be measured; a detector configured to at least receive detection light reflected by the object to be detected, and the detector detects the magneto-optical effect at the preset position according to the received detection light; The magnetic field generating device comprises a magnetic field generating coil and a pulse power supply device for providing current to the magnetic field generating coil, wherein the magnetic field generating coil is configured to form a magnetic field environment at least at the preset position.

2. A magnetic detection device as claimed in claim 1, characterized in that: The pulse power supply device is a capacitor pulse power supply device.

3. A magnetic detection device as claimed in claim 1, characterized in that: The magnetic detection device also includes a signal acquisition device, which is communicatively connected with the magnetic field generating device and the detector, and is configured to synchronously acquire the current of the magnetic field generating coil and the signal of the detector.

4. A magnetic detection device as claimed in claim 1, characterized in that: The magneto-optical effect detection component comprises the light source and the detector, and two magneto-optical effect detection components are respectively arranged on both sides of the object to be detected.

5. A magnetic detection device as claimed in claim 4, characterized in that: At least one magnetic field generating coil is respectively arranged on both sides of the object to be measured.

6. A magnetic detection device as claimed in claim 5, characterized in that: The two magnetic field generating coils are symmetrically arranged on two sides of the object to be measured.

7. A magnetic detection device as claimed in claim 1, characterized in that: The detection light passes through the magnetic field generating coil and enters the object to be measured.

8. A magnetic detection device as claimed in claim 1, characterized in that: The axis of the magnetic field generating coil is perpendicular to the surface of the object being measured.

9. A magnetic detection device as claimed in claim 1, characterized in that: The magnetic detection device further comprises a stage, and the stage is configured to support the object to be detected.

10. A magnetic detection device as claimed in claim 9, characterized in that: The stage can at least drive the object to be measured to move in a direction parallel to the plane where the surface of the object to be measured is located.

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