A magnetic field generating device

Abstract

This invention provides a magnetic field generating device, including an excitation coil, a pulse power supply device, a magnetic field monitoring device, and a computing device. The excitation coil is configured to generate a magnetic field in a preset area. The magnetic field monitoring device includes a light source, a polarizer, a Faraday rotator, and a detector. The Faraday rotator is disposed in the preset area, and the detector is communicatively connected to the computing device. This device can provide a rapidly changing magnetic field to the object under test while simultaneously monitoring the magnetic field with high precision and low latency for analysis. It can retain high-frequency magnetic field data, improve the synchronization between the magnetic detection results of the object under test and the magnetic field environment data, and facilitate the magnetic analysis of the object under test. It also allows for easy feedback control of the rapidly changing magnetic field to meet corresponding magnetic field requirements.

Description

Technical Field

[0001] This utility model belongs to the field of magnetic material detection technology, and relates to a device for generating the magnetic field environment of a magneto-optical Kerr device, specifically a magnetic field generating device. Background Technology

[0002] Magnetic material testing is of great significance in physics, materials science, electronics, and industrial production. In some cases, it is necessary to construct a specific magnetic field environment at the test location of the object to detect the magnetic characteristics exhibited by the object under the corresponding magnetic field environment, thereby analyzing the magnetic properties of the object. Therefore, the device for generating the magnetic field environment is an important component required for magnetic testing.

[0003] In practical applications, the magnetic field generated by a magnetic field generator is typically monitored by monitoring the current flowing through it. However, since the actual and theoretical structures of a magnetic field generator are rarely identical, a discrepancy arises between the magnetic field calculated from the current and the actual magnetic field, making it difficult to accurately determine the magnetic field environment of the object being measured. Therefore, existing technologies employ magnetic field sensors such as Hall effect meters within the range of the magnetic field generated by the generator to monitor the magnetic field. However, when the magnetic field changes rapidly, the limited bandwidth of the Hall effect meter leads to high-frequency data loss, resulting in the loss of data on the rapidly changing magnetic field at certain times. Furthermore, data delays can cause the magnetic field detected by the Hall effect meter to become out of sync with the actual magnetic field, thus affecting data analysis.

[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 that existing magnetic field monitoring methods in magnetic field generating devices affect the data analysis of rapidly changing magnetic fields, this application provides a magnetic field generating device, including an excitation coil, a pulse power supply device, a magnetic field monitoring device, and a computing device. The pulse power supply device is electrically connected to the excitation coil, which is configured to generate a magnetic field in a preset area. The magnetic field monitoring device includes a light source, a polarizer, a Faraday rotator, and a detector. Light emitted from the light source passes through the polarizer and the Faraday rotator before entering the detector. The detector is configured to output a corresponding signal based on the polarization state of the incident light. The Faraday rotator is located in the preset area, and the detector is communicatively connected to the computing device.

[0006] According to one embodiment of this application, the magnetic field monitoring device further includes a reflector disposed on the side of the Faraday rotator away from the light source.

[0007] According to one embodiment of this application, the light emitted by the light source is incident on the reflector after passing through at least the Faraday rotator, and the reflector is configured to make the incident light and the reflected light parallel; the magnetic field monitoring device further includes a beam splitter, and the light emitted by the light source passes through at least the beam splitter and the Faraday rotator before incident on the reflector, and the light reflected by the reflector passes through at least the Faraday rotator and the beam splitter before incident on the detector.

[0008] According to one embodiment of this application, the preset region is located inside the excitation coil.

[0009] According to one embodiment of this application, the preset region is arranged along the axis of the excitation coil.

[0010] According to one embodiment of this application, the incident light from the Faraday rotator is parallel to the axis of the excitation coil.

[0011] According to one embodiment of this application, the detector includes an analyzer and a light sensor. Light incident on the detector passes through the analyzer and then enters the light sensor. The light sensor is configured to output a corresponding signal based on the light intensity of the light incident on the light sensor.

[0012] According to one embodiment of this application, the detector includes a Wollaston prism, a first light sensor, and a second light sensor. Light incident on the detector is divided into two beams after passing through the Wollaston prism and is incident on the first light sensor and the second light sensor respectively. The first light sensor and the second light sensor are configured to output corresponding signals based on the light intensity of the light incident on the light sensor.

[0013] According to one embodiment of this application, the pulse power supply device includes at least one capacitor.

[0014] According to one embodiment of this application, the signal output by the computing device responds to the energizing state of the excitation coil.

[0015] This invention has at least the following beneficial effects: This application provides an ultrafast magnetic field for the detection of the test object by combining an excitation coil and a pulse power supply device. The magnetic field monitoring device monitors the ultrafast magnetic field, enabling high-precision and low-delay monitoring of the magnetic field for analysis of the test object while providing a rapidly changing magnetic field to it. It can retain high-frequency magnetic field data, improve the synchronization between the magnetic detection results of the test object and the magnetic field environment data, and facilitate the magnetic analysis of the test object. It also facilitates feedback control of the rapidly changing magnetic field to meet the corresponding magnetic field requirements. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the overall structure of one embodiment of a magnetic field generating device.

[0017] Figure 2 This is a schematic diagram of the overall structure of one embodiment of a magnetic field generating device.

[0018] Figure 3 This is a schematic diagram illustrating one embodiment of the relative positional relationship between a Faraday rotator and a mirror.

[0019] Figure 4 This is a schematic diagram illustrating one embodiment of the relative positional relationship between a Faraday rotator and a mirror. Detailed Implementation

[0020] 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.

[0021] This application provides a magnetic field generating device, including an excitation coil 1, a magnetic field monitoring device, a pulse power supply device 3, and a computing device 4. The pulse power supply device 3 is electrically connected to the excitation coil 1, and the excitation coil 1 is configured to generate a magnetic field in a preset area. The preset area refers to an area where the object to be measured can be placed. Accordingly, the preset area can be either inside the excitation coil 1 or near the excitation coil 1, as long as the magnetic field at that location can be altered by the excitation coil 1.

[0022] By using an excitation coil 1 with a poleless head or magnetic core to generate a magnetic field, the influence of hysteresis and remanence of the pole or magnetic core on the rate of magnetic field change can be avoided, greatly increasing the rate of magnetic field change to meet the testing requirements in high-speed changing magnetic field environments. Using a pulse power supply device 3 to provide pulsed current to the excitation coil 1 can further increase the rate of change of the magnetic field generated by the excitation coil 1. Through the aforementioned methods, a magnetic field with a duration of milliseconds or less can be achieved for testing the object under test.

[0023] The magnetic field monitoring device includes a light source 21, a polarizer 22, a Faraday rotator 23, and a detector 24. The light emitted from the light source 21 passes through the polarizer 22 and the Faraday rotator 23 and then enters the detector 24. The detector 24 is configured to output a corresponding signal based on the polarization state of the incident light. The light emitted from the light source 21 becomes polarized light after passing through the polarizer 22. When the polarized light passes through the Faraday rotator 23, the polarization direction of the polarized light is rotated due to the influence of the magnetic field at which the Faraday rotator 23 is located. Thus, the Faraday rotator 23 establishes a correlation between the magnetic field environment and the polarization direction of the polarized light. The detector 24 receives the polarized light that has passed through the Faraday rotator 23 and analyzes the polarization state, thereby analyzing the magnetic field at which the Faraday rotator 23 is located.

[0024] A Faraday rotator 23 is disposed in a preset area for setting the object under test, so as to monitor the magnetic field of the preset area. A detector 24 is communicatively connected to a computing device 4, thereby outputting information about the magnetic field of the preset area based on the signal output by the detector 24. The Faraday rotator 23 is primarily made of magneto-optical material. When an external magnetic field is applied, the Faraday rotator 23 can rotate the polarization plane of linearly polarized light passing through it. For example, it can be made of garnet crystals such as terbium gallium garnet, or terbium-based compound crystals, terbium-doped glass, paramagnetic glass, or semiconductor materials.

[0025] The detector 24 is capable of outputting a corresponding signal based on the polarization state of the incident light. Specifically, the detector 24 can be an analyzer 241 or a photodetector 242. The analyzer 241 converts the polarization direction of the light incident on the detector 24 into light intensity information, and the photodetector 242 analyzes the light intensity information and outputs a signal corresponding to the polarization state of the light incident on the detector 24 for analyzing the magnetic field at the Faraday rotator 23. The detector 24 can also be a combination of a Wollaston prism and two photodetectors 242. The Wollaston prism splits the light incident on the detector 24 into two orthogonally polarized beams, which enter the two photodetectors 242 respectively, outputting a signal corresponding to the polarization state of the light incident on the detector 24. The signals from the two photodetectors 242 can be analyzed together to analyze the magnetic field at the Faraday rotator 23. Alternatively, optical devices such as waveplates can be used to transform and process the light incident on the detector 24 to output a corresponding signal based on the polarization state of the light incident on the detector 24 for analyzing the magnetic field at the Faraday rotator 23.

[0026] Since the detector 24 monitors the polarization state of light through optical means, and thus monitors the magnetic field of the preset area, the bandwidth of the optical detector can reach the GHz level, which is much larger than the kHz to MHz bandwidth of the Hall meter. It can respond to signal changes at the nanosecond or even picosecond level, and can monitor changes in the magnetic field in a very short time. Even for magnetic fields with a duration of milliseconds or less, it can still monitor the change process of the magnetic field with high time resolution, improve the accuracy of magnetic field monitoring, and reduce data latency.

[0027] This application provides an ultrafast magnetic field for the detection of a test object by combining an excitation coil 1 and a pulse power supply device 3. Combined with a magnetic field monitoring device, the ultrafast magnetic field can be monitored with high temporal resolution while being generated, preserving high-frequency magnetic field data. This allows for high-precision, low-latency monitoring of the magnetic field while simultaneously providing a rapidly changing magnetic field to the test object for analysis. This improves the synchronization between the magnetic detection results of the test object and the magnetic field environment data, eliminating the need for time matching and facilitating magnetic analysis. In some cases, the high temporal resolution of the magnetic field monitoring data allows for feedback control of the rapidly changing magnetic field, or adjustment of at least one of the excitation coil 1 and the pulse power supply device 3 to meet specific magnetic field requirements. Furthermore, the high accuracy and low delay of the monitored magnetic field improve the accuracy of magnetic analysis of the test object. The magnetic field generating device provided in this application can also be used to analyze the temporal relationship between the magnetic changes of the test object and the magnetic field, expanding the applicability of the magnetic field generating device.

[0028] Please see Figure 1 This illustrates a feasible implementation of the present application. In this implementation, an excitation coil 1 is used to generate a magnetic field for monitoring the object under test. The object under test can be placed inside the excitation coil 1, and correspondingly, a Faraday rotator 23 is also placed inside the excitation coil 1 to monitor the magnetic field of the object under test. A light source 21 and a detector 24 are respectively placed on opposite sides of the excitation coil 2. Light emitted from the light source 21 passes through the Faraday rotator 23 and enters the detector 24 to monitor the magnetic field near the Faraday rotator 23.

[0029] In some cases, the path of the light emitted by the light source 21 can be configured to adapt to the corresponding magnetic field monitoring requirements. As a feasible implementation, the magnetic field monitoring device also includes a reflector 25, which is disposed on the side of the Faraday rotator 23 away from the light source 21. In some cases, the light passing through the Faraday rotator 23 can be reflected by the reflector 25 and then enter the detector 24 or re-enter the Faraday rotator 23 to make corresponding adjustments to the optical path.

[0030] When light passing through Faraday rotator 23 is reflected by mirror 25 and re-enters Faraday rotator 23, the light passes through Faraday rotator 23 twice. This causes the polarization direction of the light to rotate twice due to the influence of the magnetic field of Faraday rotator 23, thereby increasing the rotation angle of the polarization direction of the light. This improves the signal-to-noise ratio of the light received by detector 24, enabling more accurate analysis of the magnetic field of Faraday rotator 23.

[0031] As a feasible implementation, the light emitted by the light source 21 is incident on the reflector 25 after passing through the Faraday rotator 23 at least. The reflector 25 is configured to make the incident light and the reflected light parallel. In some cases, the incident light and the reflected light can be made parallel to each other and opposite in direction, so that the light source 21, the polarizer 22, the Faraday rotator 23, and the detector 24 are placed on the same side of the reflector 25, thereby making the overall structure of the magnetic field monitoring device more compact.

[0032] Specifically, the incident light can be incident perpendicular to the reflector 25 so that the reflected light shares at least part of the optical path with the incident light; multiple reflectors 25 can also be used in combination so that after the incident light is reflected by multiple reflectors 25, the outgoing light is parallel to the incident light.

[0033] Please see Figure 3 , Figure 4 The diagram shows two different arrangements of the positional relationship between the reflector 25 and the Faraday rotator 23. Please refer to [the diagram for details]. Figure 3 The reflector 25 can be separately mounted from the Faraday rotator 23. Please refer to [link / reference]. Figure 4 The reflector 25 can also be mounted on the Faraday rotator 23; users can select and adjust it according to actual needs based on the concept of this application.

[0034] In some cases, the magnetic field monitoring device also includes a beam splitter 26. The light emitted from the light source 21 passes through at least the beam splitter 26 and the Faraday rotator 23 before entering the reflector 25. The light reflected by the reflector 25 passes through at least the Faraday rotator 23 and the beam splitter 26 before entering the detector 24. For the light entering the reflector 25 and the light reflected by the reflector 25, the beam splitter 26 can be configured as needed to guide the light entering the reflector 25 to the reflector 25 and the light reflected by the reflector 25 to the detector 24.

[0035] As one possible implementation method, please refer to Figure 2 The light emitted by the light source 21 passes through the polarizer 22 and the beam splitter 26 to enter the Faraday rotator 23 and then the reflector 25. The light reflected by the reflector 25 passes through the Faraday rotator 23 and is reflected by the beam splitter 26 to enter the detector 24.

[0036] Please see Figure 1 , Figure 2 The Faraday rotator 23 is used to set the preset area for the object to be measured and can be placed inside the excitation coil 1 to obtain a relatively stable magnetic field. In use, the object to be measured can be placed within the preset area inside the excitation coil 1, and the Faraday rotator 23 can be positioned close to the object to be measured.

[0037] As a more user-friendly implementation method, the preset area can be set along the axis of the excitation coil 1 so that the direction of the magnetic field in the preset area is approximately along the axis of the excitation coil 1, so as to facilitate the determination of the direction of the magnetic field of the object under test and the Faraday rotator 23.

[0038] Please see Figure 1 , Figure 2 As a feasible implementation method, the incident light of the Faraday rotator 23 is parallel to the axis of the excitation coil 1, so that the direction of the magnetic field of the Faraday rotator 23 is parallel to the direction of the incident light, thereby reducing or avoiding the change in the polarization direction of the incident light caused by the magnetic field perpendicular to the direction of the incident light, thus more accurately monitoring the intensity of the magnetic field in the preset area where the Faraday rotator 23 is located, and at the same time being able to know the direction of the magnetic field in the preset area.

[0039] In some cases, detector 24 may include analyzer 241 and light sensor 242. Light incident on detector 24 passes through analyzer 241 and then enters light sensor 242. Light sensor 242 is configured to output a corresponding signal based on the light intensity of light incident on light sensor 242.

[0040] In some cases, detector 24 may include a Wollaston prism, a first light sensor, and a second light sensor. Light incident on detector 24 is divided into two beams after passing through the Wollaston prism and is incident on the first light sensor and the second light sensor respectively. The first light sensor and the second light sensor are configured to output corresponding signals based on the light intensity of the light incident on the light sensor.

[0041] The light sensor 242 can be a photodetector, a camera, a sensor array, or any other device, as long as it can output a corresponding signal based on the light intensity. The processing unit 4 receives the signal output by the light sensor 242 and analyzes the magnetic field strength of the preset area where the Faraday rotator 23 is located based on the signal output by the light sensor 242, so as to realize the monitoring of the magnetic field of the preset area.

[0042] In some cases, the pulse power supply device 3 can be a capacitor energy storage pulse power supply device, and correspondingly, the pulse power supply device 3 includes at least one capacitor. As a feasible implementation, the capacitor energy storage power supply device may include a capacitor charging circuit, a capacitor, and a capacitor discharging circuit. The capacitor is connected to an external power source through the capacitor charging circuit, and the excitation coil 1 is connected to the capacitor through the capacitor discharging circuit.

[0043] The pulse current supplied by the pulse power supply device 3 to the excitation coil 1 can be a single pulse or multiple pulses; it can be a positive pulse, a negative pulse, or multiple pulses containing both positive and negative pulses; the waveform of the pulse current is not limited here and can be adjusted as needed.

[0044] In some cases, the data processing time of the arithmetic unit 4 can be configured so that when the excitation coil 1 generates a magnetic field, the arithmetic unit 4 processes data synchronously to monitor the magnetic field synchronously. Accordingly, the signal output by the arithmetic unit 4 can respond to the energizing state of the excitation coil 1, so that when the excitation coil 1 is energized, the arithmetic unit 4 outputs a corresponding signal to monitor the magnetic field generated by the excitation coil 1.

[0045] 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 field generating device, characterized in that: It includes an excitation coil, a pulse power supply device, a magnetic field monitoring device, and a computing device. The pulse power supply device is electrically connected to the excitation coil, and the excitation coil is configured to generate a magnetic field in a preset area. The magnetic field monitoring device includes a light source, a polarizer, a Faraday rotator, and a detector. The light emitted by the light source passes through the polarizer and the Faraday rotator and then enters the detector. The detector is configured to output a corresponding signal according to the polarization state of the incident light. The Faraday rotator is located in the preset area, and the detector is communicatively connected to the computing device.

2. The magnetic field generating device as described in claim 1, characterized in that: The magnetic field monitoring device also includes a reflector, which is disposed on the side of the Faraday rotator away from the light source.

3. The magnetic field generating device as described in claim 2, characterized in that: The light emitted by the light source passes through the Faraday rotator at least before entering the reflector, and the reflector is configured to make the incident light and the reflected light parallel; the magnetic field monitoring device also includes a beam splitter, and the light emitted by the light source passes through the beam splitter and the Faraday rotator at least before entering the reflector, and the light reflected by the reflector passes through the Faraday rotator and the beam splitter at least before entering the detector.

4. The magnetic field generating device as described in claim 1, characterized in that: The preset area is located inside the excitation coil.

5. A magnetic field generating device as described in claim 1, characterized in that: The preset area is set along the axis of the excitation coil.

6. The magnetic field generating device as described in claim 1, characterized in that: The incident light from the Faraday rotator is parallel to the axis of the excitation coil.

7. A magnetic field generating device as described in claim 1, characterized in that: The detector includes an analyzer and a light sensor. Light incident on the detector passes through the analyzer and then enters the light sensor. The light sensor is configured to output a corresponding signal based on the light intensity incident on the light sensor.

8. A magnetic field generating device as described in claim 1, characterized in that: The detector includes a Wollaston prism, a first optical sensor, and a second optical sensor. Light incident on the detector is divided into two beams after passing through the Wollaston prism and is incident on the first optical sensor and the second optical sensor respectively. The first optical sensor and the second optical sensor are configured to output corresponding signals based on the light intensity of the light incident on the optical sensor.

9. A magnetic field generating device as described in claim 1, characterized in that: The pulse power supply device includes at least one capacitor.

10. A magnetic field generating device as described in claim 1, characterized in that: The signal output by the computing device responds to the energizing state of the excitation coil.

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