A magnetic detection device

Abstract

The utility model provides a kind of magnetic detection device, comprising: light source of sending detection light, detector according to the magnetic optical effect of the preset position detected by received detection light, magnetic field generating device, detection light is incident the preset position of measured object along the direction perpendicular to measured object, and detection light is polarized light at least in incident preset position;Magnetic field generating device includes magnetic field generating coil and pulse power supply device for providing current for magnetic field generating coil, and the axis of magnetic field generating coil is perpendicular to the surface of measured object;Without changing the structure of detection device, by switching the type of measured object set in equipment, calibration and magnetic detection of magnetic field can be realized, without additional use of magnetic field sensor and other equipment for calibration, greatly simplify the calibration process, facilitate the use of equipment.

Description

Technical Field

[0001] This utility model belongs to the field of magnetic variable measurement technology, and relates to measurement using the magneto-optical effect. Specifically, it relates to a magnetic detection device. Background Technology

[0002] The magneto-optical effect refers to the change in polarization state of polarized light due to the magnetization state of the medium it passes through. Therefore, the magnetism of an object can be obtained by detecting the polarized light passing through it. Based on this, magneto-optical Kerr detection equipment measures the magnetism of the object's surface by emitting polarized light into it and measuring the polarization state of the reflected light; magneto-optical Faraday detection equipment measures the magnetism of the object's surface by emitting polarized light into it and measuring the polarization state of the transmitted light.

[0003] In some cases, it is necessary to place the object under test in a magnetic field environment so that its magnetism changes under the influence of the magnetic field. Magneto-optical detection equipment, such as magneto-optical Kerr detection equipment or magneto-optical Faraday detection equipment, is used to detect these changes in magnetism, thereby analyzing the magnetic properties of the object. Since the detection light needs to be irradiated onto the target location of the object to detect the magnetism at that location, the magnetic field sensor and other magnetic field measuring devices need to be set at the target location during the calibration process. This calibration process is relatively complex, time-consuming, and labor-intensive.

[0004] The information disclosed in the background section is only intended to enhance the understanding of the background of this utility model, and therefore may contain information that does not constitute prior art known to those skilled in the art. Utility Model Content

[0005] To address the problem of time-consuming and labor-intensive magnetic field calibration processes in existing technologies, this utility model provides a magnetic detection device, comprising:

[0006] A light source is configured to emit detection light, which is incident on a predetermined position of the object being measured in a direction perpendicular to the object being measured, and the detection light is polarized light at least at the predetermined position of incidence;

[0007] A detector that detects the magneto-optical effect at the preset position based on the received detection light;

[0008] A magnetic field generating device includes a magnetic field generating coil and a pulse power supply device for supplying current to the magnetic field generating coil. The magnetic field generating coil is configured to form a magnetic field environment at least at the preset position, and the axis of the magnetic field generating coil is perpendicular to the surface of the object being measured.

[0009] According to one embodiment of this application, the pulse power supply device is a capacitor pulse power supply device.

[0010] According to one embodiment of this application, the detection light passes through the object under test to illuminate the preset position.

[0011] According to one embodiment of this application, the test object includes a first test object with a first preset position and a second test object with a second preset position. The light source includes a first light source emitting a first detection light and a second light source emitting a second detection light. The first detection light passes through the first test object to illuminate the first preset position, and the second detection light passes through the second preset position. The detector includes a first detector for receiving the first detection light and a second detector for receiving the second detection light.

[0012] According to one embodiment of this application, the first detection light enters the first detector after being reflected by the first preset position.

[0013] According to one embodiment of this application, the first light source and the second light source are respectively disposed on both sides of the magnetic field generating coil.

[0014] According to one embodiment of this application, the object to be tested is disposed inside the inner ring of the magnetic field generating coil.

[0015] According to one embodiment of this application, the test object includes a first test object with a first preset position and a second test object with a second preset position, wherein the relative positions of the first test object and the second test object are fixed.

[0016] According to one embodiment of this application, the test object includes a first test object with a first preset position and a second test object with a second preset position. The first test object is fixedly disposed, and the second test object is movably disposed.

[0017] According to one embodiment of this application, the magnetic detection device further includes a beam splitter, wherein the detection light emitted by the light source is incident on the preset position at least through the beam splitter, and the detection light reflected from the preset position is incident on the detector at least through the beam splitter.

[0018] This invention has at least the following beneficial effects: It provides a magnetic detection device that, without altering the device's structure, can analyze the magnetic field at a corresponding location by using a Faraday rotator or magneto-optical material as the test object and ensuring that the detection light at least partially passes through the test object, thereby calibrating the magnetic field generated by the magnetic field generator. When testing the test object, the sample to be tested is placed in the optical path to detect the magnetism on the surface of the test object, achieving magnetic detection of the sample. Without changing the structure and components of the detection device, magnetic field calibration and magnetic detection can be achieved by switching the type of test object placed in the device, eliminating the need for additional magnetic field sensors or other equipment for calibration, greatly simplifying the calibration process and facilitating device use. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall structure of one embodiment of the magnetic detection device.

[0020] Figure 2 This is a schematic diagram of the overall structure of another embodiment of the magnetic detection device.

[0021] Figure 3 This is a schematic diagram of one implementation method for detecting light at a preset position.

[0022] Figure 4 This is a schematic diagram of another implementation method for detecting light at a preset position.

[0023] Figure 5 This is a schematic diagram of one embodiment showing the relative positions of the first and second test objects.

[0024] Figure 6 This is a schematic diagram of another embodiment showing the relative positions of the first and second test objects.

[0025] Figure 7 This is a schematic diagram of another embodiment showing the relative positions of the first and second test objects.

[0026] Figure 8 This is a schematic diagram of another embodiment showing the relative positions of the first and second test objects.

[0027] Figure 9 This is a schematic diagram of the overall structure of another embodiment of the magnetic detection device. Detailed Implementation

[0028] To make the objectives and features of this utility model clearer and easier to understand, the specific embodiments of this utility model will be further described below with reference to the accompanying drawings. It should be noted that the drawings are all in a very simplified form and use non-precise ratios, and are only used to facilitate and clearly assist in illustrating the embodiments of this utility model.

[0029] A magnetic detection device, comprising:

[0030] A light source 100 is configured to emit a detection light L. The detection light L is incident on a preset position of the object 400 along a direction perpendicular to the object being measured 400. The detection light L is polarized light at least at the incident position. The polarization of the detection light L primarily means that it can be considered largely linearly polarized light to achieve better magneto-optical effect detection. Specifically, polarizers or polarizers can be inserted into the path of the light emitted from the light source, or polarized light can be obtained through reflection or refraction. Alternatively, birefringent crystals or lenses can be inserted into the path of the light emitted from the light source, or dichroic mirrors can be inserted, etc., to obtain polarized light. Those skilled in the art can choose the specific method for obtaining polarized light according to actual needs, and will not be elaborated further here.

[0031] A detector 200 detects the magneto-optical effect at a preset position based on the received detection light L. Specifically, the magneto-optical effect can be either the magneto-optical Kerr effect or the magneto-optical Faraday effect. The detector 200 can output corresponding data or signals depending on the needs and actual configuration. The detector 200 is at least capable of detecting the polarization state or polarization direction of the detection light L. As a common form, the detector 200 may include an analyzer 210 and a photodetector 220. The analyzer 210 converts the polarization direction of the detection light L into light intensity information, and the photodetector 220 analyzes 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 be used. The Wollaston prism 230 splits the detection light L passing through the object under test 400 into two orthogonally polarized beams, which enter the photodetectors 221 and 222 respectively. The magneto-optical effect at the preset position F can be analyzed by jointly analyzing the signals from the two photodetectors 221 and 222.

[0032] The magnetic field generating device 300 includes a magnetic field generating coil 310 and a pulse power supply device 320 for supplying 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, and the axis of the magnetic field generating coil 310 is perpendicular to the surface of the object under test 400.

[0033] When the detection light L propagates at least partially within the test object 400, the polarization state of the detection light L received by the detector 200 is affected by the magneto-optical Faraday effect. By analyzing the polarization state of the received detection light L, the detector 200 can analyze the magneto-optical Faraday effect at a preset position of the test object 400 and determine the magnetism at the preset position of the test object 400. When a Faraday rotator or magneto-optical material with known magnetism is used as the test object 400, the strength of the magneto-optical Faraday effect is affected by the magnetic field at the preset position of the test object 400 through which the detection light L passes. Therefore, the magnetic field at the preset position can be calculated through the magneto-optical Faraday effect at the preset position.

[0034] When the detection light L is reflected from the surface of the object under test 400, the polarization state of the detection light L received by the detector 200 is affected by the magneto-optical Kerr effect. By analyzing the polarization state of the received detection light L, the detector 200 can analyze the magneto-optical Kerr effect at a preset position on the object under test 400. The strength of the magneto-optical Kerr effect is affected by the magnetism at the preset position on the object under test 400 through which the detection light L passes. Therefore, the magnetism at the preset position can be calculated through the magneto-optical Kerr effect at the preset position. In some cases, the detection light L can also pass through the object under test 400 to analyze the magnetism at the preset position on the object under test 400 using the Faraday effect.

[0035] Using the aforementioned method, the same magnetic detection device can be used without changing its structure. When calibrating the magnetic field generating coil 310, a Faraday rotator or magneto-optical material is used as the test object 400, and the detection light L passes through the test object 400 at least partially to analyze the magnetic field condition at the corresponding location. This is combined with the magnetic field generated by the magnetic field generating device 300, thereby calibrating the magnetic field generated by the magnetic field generating device 300. When testing the test object 400, the sample to be tested is placed in the optical path, and the detection light L is reflected or transmitted through the surface of the test object 400 to detect the magnetism of the test object 400, thus realizing the magnetic detection of the sample to be tested. During the use of the equipment, there is no need to change the structure and components of the detection device. By switching the type of test object 400 set in the equipment, the magnetic field can be calibrated. Switching the test object 400 to the sample to be tested allows for magnetic detection without the need for additional magnetic field sensors or other equipment for calibration, greatly simplifying the calibration process and facilitating the use of the equipment.

[0036] Please see Figure 1 The present invention illustrates a method of configuring a detection light L such that the detection light L is incident perpendicularly to a preset position of the test object 400, for at least the purpose of detecting the poloidal magnetism at the preset position of the test object 400 by means of the poloidal magneto-optical Kerr effect, or detecting the magnetism at the preset position of the test object 400 by means of the magneto-optical Faraday effect.

[0037] In some cases, the relative position of the object under test 400 and the magnetic field generating coil 310 can be configured such that the detection light L can at least partially pass through the inner ring of the magnetic field generating coil 310 to illuminate the object under test 400. Regarding the relative position of the object under test 400 and the magnetic field generating coil 310, the object under test 400 can be located either outside or inside the magnetic field generating coil 310. Please refer to [link / reference]. Figure 3 The diagram illustrates a form in which the object under test 400 is disposed inside the inner ring of the magnetic field generating coil 310, wherein the size of the object under test 400 is typically smaller than the size of the inner ring of the magnetic field generating coil 310.

[0038] In some cases, the magnetic detection device provided by this utility model also includes a stage 500. The stage 500 is configured to support the object 400 to be measured. It can also be a fixed structure, a displacement structure or other form for gripping or fixing the object 400 to be measured, and can be selected as needed.

[0039] In some cases, it is also necessary to enable the object under test 400 to move so as to adjust the position of the object under test as needed. Accordingly, the stage 500 can move the object under test 400 in some cases. More specifically, the stage 500 can at least move the object under test 400 in a plane parallel to the surface 401 of the object under test.

[0040] The pulse power supply device 320 can be selected as needed. As some optional implementation methods, it can be a capacitor pulse power supply device, an inductive pulse power supply device, or a mechanical energy pulse power supply device. As a preferred implementation, a capacitor pulse power supply device can be used.

[0041] In some cases, a preset position can be configured so that the detection light L illuminates the surface of the object being tested 400. Please refer to [link / reference]. Figure 3 A preset position Fa can be set to be located on the surface 401 of the object under test 400 near the light source 100, so that the detection light L can directly irradiate the preset position Fa of the object under test 400 without passing through the object under test 400, so that the reflected detection light L can be used to analyze the magnetism at the preset position Fa.

[0042] In some cases, a preset position can be configured so that the detection light L passes through the object 400 as it illuminates the preset position. Please refer to [link / reference]. Figure 4A preset position Fb can be set to be located on the surface 402 of the object under test 400 that is far from the light source 100, so that the detection light L needs to pass through the object under test 400 and illuminate the preset position Fa of the object under test 400. This allows the detection light L to be used to analyze the influence of the magneto-optical Faraday effect on the detection light during its propagation in the object under test 400 near the preset position Fb, and thus analyze the magnetism of the object under test 400 near the preset position Fb or the magnetic field near the preset position Fb.

[0043] In some cases, after the detection light L passes through the object under test 400 and illuminates the preset position Fb, it can either continue to extend outward from the object under test 400 and enter the detector 200, or a reflective element can be set at the preset position Fb to reflect the detection light L and exit the object under test 400 from the side where it entered. Accordingly, the detector 200 can be configured to be located at a relative position to the object under test 400 to receive the corresponding detection light L, and by analyzing and obtaining the detection light L, the magnetism of the object under test 400 near the preset position Fb or the magnetic field near the preset position Fb can be analyzed.

[0044] In some cases, two preset positions can be set simultaneously in the detection device. A Faraday rotator or magneto-optical material is used as the first test object 410, and one of the preset positions is set on it to obtain the magnetic field. The sample to be tested is used as the second test object 420, and the other preset position is set on it for sample magnetic detection. This allows the obtained magnetic field to match the magnetic field of the sample. The preset position Fb for obtaining the magnetic field and the preset position Fa for detecting the test object 400 can be brought close to each other so that the magnetic field obtained through the preset position Fb is substantially the same as or similar to the magnetic field at the preset position Fa, or the magnetic field at the preset position Fa can be calculated based on the magnetic field obtained through the preset position Fb.

[0045] The test object 400 includes a first test object 410 and a second test object 420. In some cases, the relative positions of the first test object 410 and the second test object 420 are fixed. Please refer to [link / reference]. Figures 5 to 9 Several possible setup methods are shown.

[0046] Please see Figure 5 The first test object 410 and the second test object 420 can be superimposed, and the preset position Fb on the first test object 410 and the preset position Fa on the second test object 420 can be brought close to each other. In some cases, the magnetic field varies little or is relatively uniform within a certain range; please refer to [reference needed]. Figure 6 The first test object 410 and the second test object 420 can be set at intervals, and the preset position Fb on the first test object 410 and the preset position Fa on the second test object 420 can be brought close to each other; please refer to Figure 7Alternatively, the first test object 410 and the second test object 420 can be stacked together, and a certain distance can be set between the preset position Fb on the first test object 410 and the preset position Fa on the second test object 420 as needed. Accordingly, in use, the first detection light L1 passes through the first test object 410 and is incident on the preset position Fb, and the first detection light L1 is reflected and exited from the first test object 410, so that the magnetic field of the preset position Fb can be detected by the corresponding detector 200; the second detection light L2 is incident on the preset position Fa on the surface of the second test object 420, so that the magnetism of the preset position Fa can be detected by the corresponding detector 200; the magnetic field at the preset position Fb on the first test object 410 is used as the magnetic field at the preset position Fa on the second test object 420, and combined with the magnetism at the preset position Fa on the second test object 420, it is used to analyze the magnetism of the second test object 420.

[0047] Please see Figure 8 In some cases, a preset distance can be set between the first test object 410 and the second test object 420. A certain distance can be set between the preset position Fb on the first test object 410 and the preset position Fa on the second test object 420 as needed, so that the detection light L1 passing through the first test object 410 passes through the first test object 410 and illuminates the preset position Fb before directly exiting the first test object 410 and entering the detector 200 for detection. Accordingly, in use, the first detection light L1 passes through the first test object 410 and is incident on the preset position Fb and then exits the first test object 410, so that the magnetic field at the preset position Fb can be detected by the corresponding detector 200; the second detection light L2 is incident on the preset position Fa on the surface of the second test object 420, so that the magnetism at the preset position Fa can be detected by the corresponding detector 200; the magnetic field at the preset position Fb on the first test object 410 is used as the magnetic field at the preset position Fa on the second test object 420, and combined with the magnetism at the preset position Fa on the second test object 420, it is used to analyze the magnetism of the second test object 420.

[0048] In some cases, the first test object 410 can be fixedly set, while the second test object 420 can be movably set, so that the first test object 410 remains in a fixed position. When different test samples need to be tested, only different test samples need to be set as the second test object 420 in the testing device. When different positions of the second test object 420 need to be tested, only the second test object 420 needs to be moved to adjust the position of the detection light L2 illuminating it. During the aforementioned use, there is no need to adjust the first test object 410, which facilitates the use of the testing device.

[0049] In some cases, the first detection light L1 enters the first detector 201 after being reflected by a preset position Fb on the first object under test 410; alternatively, the first detection light L1 passes through the first object under test 410 and then through the preset position Fb on the first object under test 410 before entering the first detector 201. Please refer to [link to relevant documentation]. Figures 5 to 7 Several forms of reflection of the first detection light L1 at a preset position Fb on the first test object 410 are shown, and the reflected first detection light L1 is used to incident on the first detector 201; please refer to Figure 8 The diagram shows a first detection light L1 that passes through a first test object 410 and passes through a preset position Fb on the first test object 410. The transmitted first detection light L1 is used to incident on the first detector 201.

[0050] In one feasible implementation, the test object 400 includes a first test object 410 and a second test object 420. The light source 100 includes a first light source 101 emitting a first detection light and a second light source 102 emitting a second detection light. The first detection light passes through the first test object 410 to illuminate a preset position on the first test object 410, and the second detection light passes through a preset position on the second test object 420. The detector includes a first detector 201 for receiving the first detection light and a second detector 202 for receiving the second detection light. The first detection light can be reflected from the preset position on the test object 410 and exit the test object 410 before entering the corresponding first detector 201, or it can pass through the test object 410 to enter the first detector 201. Similarly, the second detection light can be reflected from the second test object 420 to enter the second detector 202, or it can pass through the second test object 420 to enter the second detector 202.

[0051] Please see Figure 9 This paper illustrates a feasible implementation method, in which a first light source 101 and a second light source 102 are respectively disposed on both sides of a magnetic field generating coil 310, and a first test object 410 and a second test object 420 are disposed in the magnetic field generated by the magnetic field generating coil 310. A first detection light emitted from the first light source 101 passes through the first test object 410 to illuminate a corresponding preset position. After being reflected, the first detection light exits the first test object 410 and enters the first detector 201. A second detection light emitted from the second light source 102 illuminates a preset position on the second test object 420, and after being reflected by the second test object 420, enters the second detector 202. Accordingly, when the first detection light and the second detection light illuminate the corresponding test object from both sides of the magnetic field generating coil 310, and both are reflected and enter the corresponding detector 200, the positions of the corresponding detectors 200 can be configured on both sides of the magnetic field generating coil 310.

[0052] In some cases, when one of the first detection light and the second detection light passes through the corresponding object to be measured, the corresponding detectors 200 can be configured to be located on the same side of the magnetic field generating coil 310, and the two detectors 200 can receive the first detection light and the second detection light respectively.

[0053] In some cases, when both the first detection light and the second detection light pass through the corresponding object to be measured, the corresponding detectors 200 can be configured to be located on both sides of the magnetic field generating coil 310, and the two detectors 200 can receive the first detection light and the second detection light respectively.

[0054] In some cases, the first detection light L1 can be configured to be reflected at a first preset position Fb; in other cases, the first detection light L1 can be configured to be reflected after passing through the first preset position Fb. Those skilled in the art can make adjustments based on this application and according to actual needs.

[0055] In some cases, the magnetic detection device provided in this application further includes a beam splitter 600, wherein the detection light emitted from the light source 100 is incident on the preset position via the beam splitter 600 at least once, and the detection light reflected from the preset position is incident on the detector 200 via the beam splitter 600 at least once. Please refer to... Figure 1 , Figure 3 , Figure 8 When the detection light is incident perpendicularly on the object 400, the detection light reflected by the object 400 will return along the incident light path. Accordingly, by setting a beam splitter 600, the detection light incident on the object 400 and the detection light reflected by the object 400 are separated, so that one of the detection light incident on the object 400 and the detection light reflected by the object 400 is transmitted through the beam splitter 600, and the other is reflected by the beam splitter 600, so that the detection light reflected by the object 400 can enter the detector 200 for corresponding analysis.

[0056] In some cases, a single magnetic field generating coil 310 is sufficient to ensure that the magnetic field environment at the preset positions F on both sides of the object under test meets the detection requirements; in other cases, a single magnetic field generating coil 310 may not be sufficient to ensure that the magnetic field environment at the preset positions F on both sides of the object under test meets the detection requirements. At least one magnetic field generating coil 310 may be installed on each side of the object under test, as needed. Alternatively, a required number of magnetic field generating coils 310 may be installed on both sides of the object under test, as required.

[0057] In some cases, in order to further improve the uniformity of the magnetic field environment near the object under test 400, two magnetic field generating coils 310 can be symmetrically arranged on both sides of the object under test 400.

[0058] As a feasible solution, 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 incident on the preset position F of the object under test 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.

[0059] As a feasible solution, the detector 200 may include an analyzer 210 and a photodetector 220. The detection light L reflected by the object under test 400 enters the photodetector 220 after passing through the analyzer 210. Based on the signal from the photodetector 220, especially the light intensity signal, the corresponding magneto-optical effect is analyzed.

[0060] To further improve the rate of change of the magnetic field generated by the magnetic field generating coil 310, the pulse power supply device 320 can be either single pulse or multi pulse, and the specific output waveform is not limited here.

[0061] The basic principles, main features, and advantages of this utility model have been shown and described above. Therefore, the above description is only an embodiment of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are only the principles of this utility model. Without departing from the spirit and scope of this utility model, this utility model also includes various equivalent changes and modifications, all of which will fall within the scope of this utility model as claimed.

Claims

1. A magnetic detection device, characterized in that, include: A light source is configured to emit detection light, which is incident on a predetermined position of the object being measured in a direction perpendicular to the object being measured, and the detection light is polarized light at least at the predetermined position of incidence; A detector that detects the magneto-optical effect at the preset position based on the received detection light; A magnetic field generating device includes a magnetic field generating coil and a pulse power supply device for supplying current to the magnetic field generating coil. The magnetic field generating coil is configured to form a magnetic field environment at least at the preset position, and the axis of the magnetic field generating coil is perpendicular to the surface of the object being measured.

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

3. The magnetic detection device as described in claim 1, characterized in that: The detection light passes through the object being tested to illuminate the preset position.

4. The magnetic detection device as described in claim 1, characterized in that: The test object includes a first test object and a second test object. The light source includes a first light source emitting a first detection light and a second light source emitting a second detection light. The first detection light passes through the first test object to illuminate the preset position on the first test object. The second detection light passes through the preset position on the second test object. The detector includes a first detector for receiving the first detection light and a second detector for receiving the second detection light.

5. A magnetic detection device as described in claim 4, characterized in that: The first detection light enters the first detector after being reflected by the preset position on the first test object, or the first detection light passes through the first test object and enters the first detector after passing through the preset position on the first test object.

6. The magnetic detection device as described in claim 4, characterized in that: The first light source and the second light source are respectively disposed on both sides of the magnetic field generating coil.

7. A magnetic detection device as described in claim 1, characterized in that: The object under test is placed inside the inner ring of the magnetic field generating coil.

8. A magnetic detection device as described in claim 1, characterized in that: The test object includes a first test object and a second test object, and the relative positions of the first test object and the second test object are fixed.

9. A magnetic detection device as described in claim 1, characterized in that: The test object includes a first test object and a second test object, wherein the first test object is fixedly installed and the second test object is movably installed.

10. A magnetic detection device as described in claim 1, characterized in that: The magnetic detection device further includes a beam splitter, wherein the detection light emitted by the light source is incident on the preset position at least through the beam splitter, and the detection light reflected from the preset position is incident on the detector at least through the beam splitter.

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