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 measurement technical field of magnetic variable, relates to utilize the measurement of magneto-optic effect, specifically, a kind of magnetic detection device. BACKGROUND

[0002] Magneto-optic Kerr effect refers to the reflection light can change due to the magnetization of reflecting medium, so the magnetism of measured object can be obtained by detecting the reflection light of the surface of measured object. On this basis, the magneto-optic Kerr detection equipment measures the polarization state of the reflection light of measured object by emitting polarized light to measured object, so as to measure the magnetism of the surface of measured object.

[0003] In some cases, it is necessary to place the measured object in a magnetic field environment so that the magnetism of the measured object changes under the influence of the magnetic field environment, and the magneto-optic Kerr detection equipment is used to detect the change of the magnetism of the measured object, so as to analyze the magnetic properties of the measured object. In the prior art, an electromagnet is usually used to generate a magnetic field, and the pole head of the electromagnet is placed close to the measured object so that the measured object is placed in a controllable magnetic field environment. However, since the pole head material in the electromagnet is prone to generating induced current during operation, which partially offsets the magnetizing effect, accordingly, the speed of generating a magnetic field by the electromagnet is usually slow, which cannot meet the testing requirements in a high-speed changing magnetic field environment. In some cases, the speed of changing the magnetic field can be improved by removing the pole head or magnetic core, but this method greatly reduces the magnetic field strength of the generated magnetic field environment, which cannot meet the testing requirements in a large magnetic field environment.

[0004] Therefore, in the existing magnetic field generation scheme, it is difficult to simultaneously satisfy the high-speed changing and large magnetic field strength magnetic field.

[0005] The above information disclosed in the background section is only used to enhance the understanding of the background of the utility model, and therefore can contain information that is not prior art known to those skilled in the art. CONTENT OF THE UTILITY MODEL

[0006] In order to provide a device capable of detecting the magnetism of measured object in a high-speed changing and large magnetic field strength magnetic field environment, the utility model provides a magnetic detection device, comprising: a light source configured to emit detection light, the detection light being polarized light at least at a preset position incident on the measured object; a detector configured to receive at least the detection light reflected by the measured object, the detector detecting magneto-optic effect at the preset position according to 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, the magnetic field generating coil being configured to form at least a magnetic field environment in the form of the preset position.

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

[0008] According to one embodiment of the utility model, the magnetic detection device further comprises a signal acquisition device, which is in communication connection 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.

[0009] According to one embodiment of the utility model, the magneto-optical effect detection assembly comprises the light source and the detector, and two of the magneto-optical effect detection assemblies are arranged on the two sides of the measured object.

[0010] According to one embodiment of the utility model, the two sides of the measured object are respectively provided with at least one of the magnetic field generating coils.

[0011] According to one embodiment of the utility model, the detection light passes through the magnetic field generating coil and is incident on the measured object.

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

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

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

[0015] According to one embodiment of the utility model, the detector comprises an analyzer and a photodetector, and the detection light reflected by the measured object passes through the analyzer and then enters the photodetector.

[0016] According to one embodiment of the utility model, the detector comprises a Wollaston prism and two photodetectors, and the detection light reflected by the measured object passes through the Wollaston prism and then enters the two photodetectors respectively.

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

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

[0019] According to one embodiment of the utility model discloses, the detection light is oblique and is incident the preset position.

[0020] According to one embodiment of the utility model discloses, the detection light is oblique and is incident the preset position.

[0021] According to one embodiment of the utility model discloses, the magnetic detection device still includes the stage, the stage is configured to support the form of measured object.

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

[0023] According to one embodiment of the utility model discloses, measured object is arranged on the inner side or the outer side of the magnetic field generating coil.

[0024] The utility model discloses at least has following beneficial effect: the utility model provides a kind of magnetic detection device, utilize the magnetic field of magnetic head or magnetic core's magnetic field generating coil generation magnetic field, can avoid the influence of magnetic hysteresis and residual magnetism of magnetic head or magnetic core on the change speed of magnetic field, greatly improve the change speed of magnetic field;The preset position to be measured of measured object is located in the magnetic field environment of magnetic field generating coil, to meet the testing demand under the high-speed change magnetic field environment, easy to adjust the magnetic field of preset position, greatly facilitate the control of magnetic field, and the use of detection equipment. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 It is the whole structure schematic view of one embodiment of magnetic detection device.

[0026] Figure 2 It is the whole structure schematic view of another embodiment of magnetic detection device.

[0027] Figure 3 It is the whole structure schematic view of another embodiment of magnetic detection device.

[0028] Figure 4 It is the whole structure schematic view of another embodiment of magnetic detection device.

[0029] Figure 5 It is the whole structure schematic view of another embodiment of magnetic detection device.

[0030] Figure 6 It is the schematic view of the relationship between preset position and magnetic field generating coil of magnetic detection device.

[0031] Figure 7 A schematic diagram of an overall structure of another embodiment of the magnetic detection device.

[0032] Figure 8 A schematic diagram of an overall structure of another embodiment of the magnetic detection device. DETAILED DESCRIPTION

[0033] To make the purpose and features of the present application more obvious and easy to understand, the specific embodiments of the present application will be further described below in conjunction with the drawings. It should be noted that the drawings are all in a very simplified form and all use non-precise ratios, and are only used for the purpose of conveniently and clearly assisting in the description of the embodiments of the present application.

[0034] The present application provides a kind of magnetic detection device, comprising: light source 100, it is configured to emit detection light L, detection light L at least at the preset position F of incidence measured object 400 is polarized light.Specifically, polarizer or polarizer can be inserted in the path of light emitted by light source, or polarization light is obtained by using reflection or refraction, or birefringent crystal or lens is inserted in the path of light emitted by light source, or dichroic mirror is inserted in the path of light emitted by light source, etc., to obtain polarization light.For the specific way of obtaining polarization light, those skilled in the art can select according to actual needs, and will not be repeated here.

[0035] For detection light L, it needs to be polarized light when it is incident on the preset position F of measured object 400, and the requirement of polarization light is not limited for detection light L in its light path, for example, polarization light can be formed in light source 100, or polarization light can be formed in the propagation process of detection light L.More specifically, the corresponding lens or optical device that makes detection light L have the characteristics of polarized light only needs to be arranged in the light path before the preset position F of measured object 400.

[0036] Detection light L is polarized light, mainly refers to detection light L can be generally regarded as linearly polarized light, to obtain better magneto-optic effect detection effect.

[0037] A detector 200 is configured to receive at least the detection light L reflected by the measured object 400, and 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 differences in actual configurations. The detector 200 is at least in the form of being able to detect the polarization state or polarization direction of the detection light L. As a more common form, the detector 200 can include an analyzer 210 and a photodetector 220. The analyzer 210 is used to convert the polarization direction of the detection light L into light intensity information, and then the photodetector 220 is used to analyze the light intensity information 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 Wollaston prism 230 is used to divide the detection light L reflected by the measured object 400 into two beams of orthogonal polarized light, and the two beams of orthogonal polarized light enter 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.

[0038] A 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 at least form a magnetic field environment at the preset position F, and the pulse power supply device 320 provides current to the magnetic field generating coil 310 to generate a magnetic field environment.

[0039] Through the foregoing arrangement, the magnetic field generating coil 310 with a pole head or a magnetic core is used to generate a magnetic field, which can avoid the influence of hysteresis and residual magnetism of the pole head or the magnetic core on the change speed of the magnetic field, greatly improve the change speed of the magnetic field, and make the preset position F to be measured of the measured object 400 located in the magnetic field environment of the magnetic field generating coil 310 to meet the testing requirements in the high-speed changing magnetic field environment. The pulse power supply device 320 is used to provide current to the magnetic field generating coil 310, which can provide at least a large instantaneous current to the magnetic field generating coil 310 to further enhance the magnetic field strength generated by the magnetic field generating coil 310. Using the present scheme, a high-speed changing large magnetic field can be obtained, which can meet the detection requirements of high-speed large magnetic field.

[0040] In some cases, a corresponding magnetic core can also be arranged near the magnetic field generating coil 310 according to the needs, 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 change speed of the magnetic field at the preset position F is reduced to meet the corresponding detection requirements.

[0041] For the measured position of the measured object 400, i.e. the preset position F, the relative position between the preset position F and the magnetic field generating coil 310 can be set to determine 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 projection S1 of the inner ring 311 of the magnetic field generating coil 310. Please refer to Figure 6 , which shows a specific position setting mode. The magnetic field generating coil 310 can be in the shape of a circular ring, which contains 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 measured object 400, and the preset position F is located within the projection range S1. In some cases, the space in the inner ring of the magnetic field generating coil 310 is sufficient to accommodate the measured object 400. Accordingly, the surface 410 of the measured object 400 can be located inside or outside the magnetic field generating coil 310. Specifically, Figure 5 shows a form of the measured object 400, which at least includes the surface 410 located within the inner ring 311 of the magnetic field generating coil 310, i.e. the form of the surface 410 of the measured object 400 located inside the magnetic field generating coil 310; Figures 1 to 4 、 Figure 7 、 Figure 8 respectively show forms of the surface 410 of the measured object 400 located outside the magnetic field generating coil 310. It should be noted that the measured object 400 is located inside or outside the magnetic field generating coil 310 mainly refers to that the measured surface 410 of the measured object 400 is located inside or outside the magnetic field generating coil 310.

[0042] 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, 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 measured object 400, so that the magnetic field at the preset position F is easier to control and calculate. It should be noted that when the surface 410 of the measured object 400 is located inside or outside the magnetic field generating coil 310, the configuration mode of the preset position F located within the projection range S1 can be formed.

[0043] In addition, since the preset position F is located within 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 is easy to adjust the magnetic field at the preset position F, greatly facilitating 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 light path of the detection light L, which can simplify the optical path structure of the equipment and reduce the cost of the equipment.

[0044] 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, by the minimum cross section of the inner ring 311 to determine the range of the projection S1.

[0045] As an optional embodiment, the pulse power supply device 320 can be selected as needed, for example, it can be a capacitive pulse power supply device, an inductive pulse power supply device, a mechanical energy pulse power supply device. As a better implementation, a capacitive pulse power supply device can be used.

[0046] In some cases, a signal acquisition device can be further provided on the basis of the technical scheme of the utility model, the signal acquisition device is in communication connection with the magnetic field generating device and the detector, and the signal acquisition device is configured 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 data of the magnetic field and the magnetism at the preset position F, the magnetic properties of the measured object can be analyzed.

[0047] In some cases, the measured object 400 has magnetic detection requirements on both sides, accordingly, the light source 100 and the detector 200 can be used as a magneto-optical effect detection assembly, and at least one magneto-optical effect detection assembly can be arranged on both sides of the measured object 400 which has detection requirements, so as to realize double-sided detection of the measured object 400. Please refer to Figure 7 , which shows a specific embodiment provided with two magneto-optical effect detection assemblies, wherein the first light source 100 and the first detector 200 are used as a first magneto-optical effect detection assembly and are arranged on the left side of the measured object 400; the second light source 100' and the second detector 200' are used as a second magneto-optical effect detection assembly and are arranged on the right side of the measured object 400, and the two magneto-optical effect detection assemblies can detect the magnetism on both sides of the measured object.

[0048] When detecting the magnetism on both sides of the measured object 400, 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 measured object 400 meet the detection requirements; in another part of the case, one magnetic field generating coil 310 is difficult to make the magnetic field environment at the preset position F on both sides of the measured object 400 meet the detection requirements. At least one magnetic field generating coil 310 can be arranged on both sides of the measured object 400 as needed. Of course, the required number of magnetic field generating coils 310 can also be arranged on both sides of the measured object 400 as needed. Please refer to Figure 7, show a specific embodiment, wherein the magnetic field generating coil 310 is arranged at the left side of the measured object 400, and the magnetic field generating coil 310' is arranged at the right side of the measured object 400. In some cases, a slit can also be arranged in the magnetic field generating coil, and the measured object 400 is arranged in the slit, although the magnetic field generating coil seems to have only one, but in essence, it has very similar functions and effects as using two magnetic field generating coils; the connection between the magnetic field generating coils on both sides of the slit plays the role of connecting the coils on both sides of the slit, and the magnetic field generating coils on both sides of the slit can be equivalent to two magnetic field generating coils in essence. That is, the way of arranging a slit in the magnetic field generating coil is equivalent to the way of arranging two magnetic field generating coils.

[0049] In some cases, in order to further make the magnetic field environment of the preset position F on both sides of the measured object 400 the same, the two magnetic field generating coils 310, 310' can be arranged symmetrically on both sides of the measured object 400.

[0050] In some cases, the performance or structure of the magnetic field generating coils 310, 310' is 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 positional relationship between the coils 310, 310' and the measured object 400 is configured to configure the magnetic field environment in which the measured object 400 is located.

[0051] When two magnetic field generating coils 310, 310' are arranged, in some cases, it is necessary to make the two magnetic field generating coils 310, 310' generate magnetic fields at substantially the same time, accordingly, please refer to Figure 7 , the magnetic field generating coils 310, 310' arranged on both sides of the measured object 400 can be connected to the same pulse power supply device 320, for example, connected in series, in parallel or other ways to the same pulse power supply device 320, please refer to Figure 8 , or the magnetic field generating coils 310, 310' arranged on both sides of the measured object 400 can be connected to different pulse power supply devices 320, 320' and the pulse power supply devices 320, 320' are controlled synchronously, so that the currents of the two magnetic field generating coils 310, 310' are substantially synchronized.

[0052] As a more feasible scheme, 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 detection light L incident on the preset position F of the measured object 400. For the light emitting device 110, a laser light source can be selected, a light emitting diode light source can also be selected, or other devices capable of generating light can be selected as the light emitting device 110.

[0053] Please refer to Figure 1 ,3 , 4, the detector 200 can include a polarizer 210, photodetector 220, the measured object 400 reflected detection light L through the polarizer 210 into the photodetector 220, according to the photodetector 220 signal, especially light intensity signal, analysis of the corresponding magneto-optical effect.

[0054] Please refer to Figure 2 , shows another detector 200 scheme, wherein the detector 200 can include a Wollaston prism 230, two photodetectors 221, 222, the measured object 400 reflected detection light L through the Wollaston prism 230, respectively into two photodetectors 221, 222, by two photodetectors 221, 222 between the operation, for example, the difference between the two photodetectors 221, 222 signal to analyze the corresponding magneto-optical effect.

[0055] Please refer to Figure 6 , as a good effect of the embodiment, the axis of the magnetic field generating coil 310 and the measured object 400 surface 410 perpendicular to at least part of the region on the surface 410 of the measured object 400 to form a substantially perpendicular to the surface 410 of the measured object 400 magnetic field. In this case, the projection S1 of the inner ring 311 of the magnetic field generating coil 310 can be formed within the scope of a more uniform and substantially perpendicular to the surface 410 of the measured object 400 magnetic field.

[0056] In order to further improve the speed of change of the magnetic field generated by the magnetic field generating coil 310, the pulse power supply device 320, which can be a single pulse, can also be a multi-pulse, for the specific output waveform, not limited here.

[0057] Please refer to Figure 1 , 2 , the detection light L can be incident in the direction perpendicular to the measured object 400 at the preset position F to detect at least the polar Kerr effect at the preset position F. At this time, the light path can also be provided with a beam splitter 600, the detection light L emitted by the light source 100 is incident on the preset position F through the beam splitter 600, and the detection light L reflected by the measured object 400 is incident on the detector 200 through the beam splitter 600. As a feasible way, please refer to the specific path of the detection light L1 in Figure 6 In this case, at least the vertical direction of the measured object 400 can be detected by the detector 200.

[0058] Please refer to Figure 3 , Figure 4 , the detection light L can also be incident obliquely at the preset position F, 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 and the vertical direction of the surface 401 of the measured object 400 form an angle, as a feasible way, please refer toFigure 6 In this case, the angle of incidence of the detection light L2 on the measured object 400 can be adjusted to detect the in-plane direction and the vertical direction of the magnetism of the measured object 400. Generally, a smaller angle of incidence can be used to mainly analyze the vertical direction of the magnetism at the preset position F of the measured object 400, and a larger angle of incidence can be used to mainly analyze the vertical direction and the in-plane direction of the magnetism at the preset position F of the measured object 400.

[0059] Referring to Figures 1 to 6 The magnetic detection device provided by the utility model further comprises a carrier table 500 which is configured to support the measured object 400. Specifically, the carrier table 500 can provide an area on which the measured object 400 is placed, and can further provide a fixing effect on the measured object 400. As for the specific form of the carrier table 500, in addition to the platform form for supporting the measured object 400, the carrier table 500 can also be in the form of a fixing structure or a displacement structure for grabbing or fixing the measured object 400, and the form can be selected as required.

[0060] In some cases, the measured object 400 needs to be moved to adjust the position to be detected as required. Accordingly, the carrier table 500 can drive the measured object 400 to move in some cases. More specifically, the carrier table 500 can at least drive the measured object 400 to move in a plane parallel to the surface 401 of the measured object.

[0061] The basic principles, main features and advantages of the utility model are shown and described above, and therefore the above description is only an embodiment of the utility model. It should be understood by those skilled in the art that the utility model is not limited by the above embodiment, and the above embodiment and the description in the specification are only 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, and these changes and improvements will fall within the scope of the claimed utility model.

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 predetermined 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 measured, and detect 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, wherein the magnetic field generating coil is configured to form a magnetic field environment at least at the preset position; The object to be measured is arranged inside the magnetic field generating coil.

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

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

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

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

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

7. A magnetic detection device according to claim 1, characterized in that: The magnetic detection device further includes a stage, which is configured to support the object to be detected.

8. A magnetic detection device according to claim 7, 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.

Images