Magnetic field intensity determination system, method, equipment and medium

Abstract

The invention discloses a magnetic field intensity determination system, method, device and medium, the system comprises a magnetic field area module, a laser emission module, a signal processing module and a data processing module, the magnetic field area module comprises two magnetic field generation units, a magneto-optical medium and a displacement platform; the laser emitting module emits a laser signal to the magnetic field area module, receives the laser signal modulated by the magnetic field area module, generates a self-mixing interference signal and reflects the self-mixing interference signal to the signal processing module; the magneto-optical medium changes a polarization plane of a passing laser signal under the action of a magnetic field of the magnetic field area; the displacement platform generates displacement, modulates a laser signal transmitted by the magneto-optical medium, and reflects the laser signal modulated by the displacement back to the magneto-optical medium; the signal processing module processes the self-mixing interference signal, generates a to-be-detected electric signal and sends the to-be-detected electric signal to the data processing module so as to determine the magnetic field intensity of the magnetic field area. The system is simple in structure, high in sensitivity, high in anti-interference capability, low in cost and high in precision.

Description

Technical Field

[0001] The present invention relates to the field of laser technology, and in particular to a magnetic field intensity determination system, method, device and medium. Background Art

[0002] Magnetic field measurement is one of the basic tools for physics research. It is used to explore the fundamental properties of matter, such as the magnetization process of magnetic materials and the Meissner effect of superconductors. In particle physics, magnetic fields are used to control the trajectory of charged particles, for example, in the Large Hadron Collider (LHC), magnetic fields are used to precisely control the path of particle beams.

[0003] In recent years, scholars from various countries have done a lot of research on fiber optic magnetic field sensors for magnetic field measurement. According to the measurement mechanism, they can be divided into types based on Faraday effect optical rotation, based on magnetic fluid refractive index, and based on magnetostrictive effect. Among them, magnetic fluid is a special functional material whose refractive index changes with the magnetic field. Combining magnetic fluid materials with micro-nano optical fibers is conducive to further improving the sensitivity of fiber optic magnetic field sensors; giant magnetostrictive materials will undergo physical deformation according to the magnetic field conditions, and can achieve more energy forms conversion with alternating magnetic fields, with good linearity and reversibility.

[0004] However, the refractive index type fiber optic magnetic field sensor is limited by the characteristics of both materials, has a small measurement range, and can only be applied to some specific fields. Giant magnetostrictive materials are temperature sensitive, and fiber optic magnetic field sensors are affected by external temperature and need to be calibrated. Summary of the invention

[0005] The present invention provides a magnetic field strength determination system, method, device and medium to achieve measurement of magnetic field strength.

[0006] According to a first aspect of the present invention, a magnetic field strength determination system is provided, the system comprising: a magnetic field region module, a laser emission module, a signal processing module and a data processing module, the magnetic field region module comprising two magnetic field generating units, a magneto-optical medium and a displacement platform, the two magnetic field generating units are symmetrically placed according to a preset air gap, and the magneto-optical medium is arranged between the two magnetic field generating units;

[0007] The two magnetic field generating units are used to generate a magnetic field region to be measured between a preset air gap based on a set current;

[0008] The laser emitting module is used to emit a laser signal to the magnetic field region module, receive the laser signal modulated by the magnetic field region module, and generate a self-mixed interference signal to be reflected to the signal processing module;

[0009] The magneto-optical medium is used to change the polarization plane of the laser signal passing through under the action of the magnetic field of the magnetic field region;

[0010] The displacement platform is used to generate a displacement, modulate the laser signal transmitted by the magneto-optical medium by the displacement, and reflect the laser signal modulated by the displacement back to the magneto-optical medium;

[0011] The signal processing module is used to process the self-mixing interference signal, generate an electrical signal to be detected and send it to the data processing module;

[0012] The data processing module is used to determine the magnetic field strength of the magnetic field area according to the output power of the electrical signal to be detected.

[0013] According to a second aspect of the present invention, a method for determining magnetic field strength is provided, characterized in that the method is applied to a magnetic field strength determination system as described in any embodiment of the present invention, the system comprising: a magnetic field area module, a laser emission module, a signal processing module and a data processing module, the magnetic field area module comprising two magnetic field generating units, a magneto-optical medium and a displacement platform, the two magnetic field generating units are symmetrically placed according to a preset air gap, the magneto-optical medium is arranged between the two magnetic field generating units, and the method comprises:

[0014] generating a magnetic field region to be measured between the preset air gaps by using the two magnetic field generating units based on a set current;

[0015] The laser emitting module emits a laser signal to the magnetic field region module, receives the laser signal modulated by the magnetic field region module, and generates a self-mixed interference signal to be reflected to the signal processing module;

[0016] The magneto-optical medium changes the polarization plane of the laser signal passing through the magneto-optical medium under the action of the magnetic field in the magnetic field region;

[0017] Generate a displacement through the displacement platform, modulate the laser signal transmitted by the magneto-optical medium through the displacement, and reflect the laser signal modulated by the displacement back to the magneto-optical medium;

[0018] Processing the self-mixing interference signal through the signal processing module to generate an electrical signal to be detected and sending it to the data processing module;

[0019] The magnetic field strength of the magnetic field area is determined by the data processing module according to the output power of the electrical signal to be detected.

[0020] According to a third aspect of the present invention, a computer device is provided, wherein the computer device is used as an execution subject of each module in the magnetic field strength determination system according to any embodiment of the present invention, and comprises:

[0021] at least one processor; and

[0022] a memory communicatively connected to the at least one processor; wherein,

[0023] The memory stores a computer program executable by the at least one processor, and the computer program is executed by the at least one processor so that the at least one processor can execute the magnetic field strength determination system described in any embodiment of the present invention.

[0024] According to a fourth aspect of the present invention, a computer-readable storage medium is provided, wherein the computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a processor to implement the method for determining magnetic field strength described in any embodiment of the present invention when executed.

[0025] The technical solution of the embodiment of the present invention is to establish a magnetic field strength determination system, the system includes: a magnetic field area module, a laser emission module, a signal processing module and a data processing module, the magnetic field area module includes two magnetic field generating units, a magneto-optical medium and a displacement platform, the two magnetic field generating units are symmetrically placed according to a preset air gap, and the magneto-optical medium is mounted between the two magnetic field generating units; the two magnetic field generating units are used to generate a magnetic field area to be measured between the preset air gaps based on a set current; the laser emission module is used to emit a laser signal to the magnetic field area module, receive the laser signal modulated by the magnetic field area module, and generate a self-mixing interference signal to reflect to the signal processing module; the magneto-optical medium is used to change the polarization plane of the laser signal passing through under the action of the magnetic field in the magnetic field area; the displacement platform is used to generate a displacement, modulate the laser signal transmitted by the magneto-optical medium by the displacement, and reflect the laser signal modulated by the displacement back to the magneto-optical medium; the signal processing module is used to process the self-mixing interference signal, generate an electrical signal to be detected and send it to the data processing module; the data processing module is used to determine the magnetic field strength of the magnetic field area according to the output power of the electrical signal to be detected. The laser can realize the functions of polarization and polarization analysis at the same time, and uses fewer optical devices, which can realize a highly compact optical system, which makes it have a lower cost. The sensitivity of magnetic field measurement is improved by magneto-optical medium, and it has strong anti-interference ability. The laser interferometer high-precision magnetic field sensor system based on the Faraday effect has the characteristics of system optical path design, simple structure, compactness and easy alignment, strong sensitivity, strong anti-interference ability and high precision.

[0026] The technical solution of the embodiment of the present invention is illustrated by the accompanying drawings

[0027] Figure 1 is a structural schematic diagram of a magnetic field strength determination system provided according to Embodiment 1 of the present invention;

[0028] Figure 2 is a structural schematic diagram of a magnetic field region module in a magnetic field strength determination system provided in accordance with Embodiment 1 of the present invention;

[0029] Figure 3 is another structural schematic diagram of a magnetic field strength determination system provided according to Embodiment 1 of the present invention;

[0030] Figure 4 is an example signal diagram of a magnetic field strength determination system provided according to Embodiment 1 of the present invention;

[0031] Figure 5 is an example diagram of errors of a magnetic field strength determination system provided in accordance with Embodiment 1 of the present invention;

[0032] Figure 6 is a flow chart of a method for determining magnetic field strength provided according to Embodiment 1 of the present invention;

[0033] Figure 7 It is a schematic diagram of the structure of a computer device implementing an embodiment of the present invention. DETAILED DESCRIPTION

[0034] The present invention is further described below in conjunction with the accompanying drawings and specific implementation methods. It should be noted that, under the premise of no conflict, the various embodiments or technical features described below can be arbitrarily combined to form a new embodiment.

[0035] Embodiment 1

[0036] Figure 1 A structural schematic diagram of a magnetic field strength determination system is provided for Embodiment 1 of the present invention. This embodiment is applicable to the determination of magnetic field strength.

[0037] like Figure 1 As shown, the system includes: a magnetic field region module 1, a laser emission module 2, a signal processing module 3 and a data processing module 4. The magnetic field region module 1 includes two magnetic field generating units 11, a magneto-optical medium 12 and a displacement platform 13. The two magnetic field generating units 11 are symmetrically placed according to a preset air gap, and the magneto-optical medium 12 is set between the two magnetic field generating units 11. The dotted line represents the propagation path of the laser signal.

[0038] The two magnetic field generating units 11 are used to generate a magnetic field region to be measured between the preset air gaps based on a set current; the laser emitting module 2 is used to emit a laser signal to the magnetic field region module 1, receive the laser signal modulated by the magnetic field region module 1, and generate a self-mixing interference signal to be reflected to the signal processing module 3; the magneto-optical medium 12 is used to change the polarization plane of the laser signal passing through under the action of the magnetic field of the magnetic field region; the displacement platform 13 is used to generate a displacement, modulate the laser signal transmitted by the magneto-optical medium 12 by the displacement, and reflect the laser signal modulated by the displacement back to the magneto-optical medium 12; the signal processing module 3 is used to process the self-mixing interference signal, generate an electrical signal to be detected and send it to the data processing module 4; the data processing module 4 is used to determine the magnetic field strength of the magnetic field region according to the output power of the electrical signal to be detected. Among them, the set current can be understood as the current used to generate the magnetic field. The preset air gap can be understood as the interval between the two magnetic field generating units 11. The magnetic field generating unit 11 is a unit for generating a magnetic field by an electric current, for example, a permanent magnet, an electromagnetic coil or any other applicable magnetic field generator. The magnetic field region can be understood as the region between the two magnetic field generating units 11 that is affected by the magnetic field. The magneto-optical medium 12 is used to react to changes in the magnetic field, and is a terbium gallium garnet crystal with a high transmittance. The terbium gallium garnet (TGG) crystal is a magneto-optical crystal with a large Verdet constant, which is sensitive to the magnetic field, and the polarization state of polarized light is changed by applying a magnetic field to the TGG crystal. The laser 21 can be a helium-neon laser 21, a semiconductor laser 21 or any other suitable laser 21. The displacement platform 13 can be a piezoelectric ceramic (Piezoelectric Ceramic Transducer, PZT) three-dimensional displacement platform 13, etc., and a reflector can be provided on the surface of the displacement platform 13 to reflect the laser signal. The self-mixing interference signal can be understood as a signal formed by the light generated by the laser diode being reflected or scattered by an external object, and part of the light returns and interferes with the light emitted by itself. The electrical signal to be detected can be understood as a signal converted into an electrical form. The output power can be understood as the light energy outputted from the laser 21. The magnetic field strength can be understood as the strength of the magnetic field that characterizes the magnetic field region.

[0039] Specifically, two magnetic field generating units 11 with horizontal magnetic field directions can be used to generate a magnetic field region to be measured between preset air gaps based on a set current. The laser emitting module 2 emits a laser signal to the magnetic field region module 1, and the laser signal passes through the magneto-optical medium 12 and hits the displacement platform 13. The magneto-optical medium 12 changes the polarization plane of the laser signal passing through under the action of the magnetic field of the magnetic field region, and the displacement platform 13 generates a displacement, modulates the laser signal passing through the magneto-optical medium 12 by the displacement, and reflects the laser signal modulated by the displacement back to the magneto-optical medium 12. Passing through the magneto-optical medium 12 twice improves the sensitivity of magnetic field measurement and has a strong anti-interference property. The magneto-optical medium 12 changes the polarization plane of the laser signal returned through the displacement platform 13 again under the action of the magnetic field of the magnetic field region. The laser emitting module 2 receives the laser signal modulated by the magnetic field region module 1, and generates a self-mixing interference signal to be reflected to the signal processing module 3. The signal processing module 3 amplifies and converts the self-mixing interference signal into an electrical signal, generates an electrical signal to be detected, and sends it to the data processing module 4. The data processing module 4 determines the magnetic field strength of the magnetic field area according to the output power of the electrical signal to be detected.

[0040] Further, Figure 2 FIG. 1 is a schematic diagram of the structure of a magnetic field region module 1 in a magnetic field strength determination system according to Embodiment 1 of the present invention. Figure 2 As shown, the magnetic field region module 1 includes two magnetic field generating units 11, a magneto-optical medium 12 and a displacement platform 13, wherein the displacement platform 13 is not shown, the two magnetic field generating units 11 are symmetrically placed according to a preset air gap, a magnetic field generating medium, such as an electromagnet, is arranged in the middle of the magnetic field generating unit 11, and a magnetic field is generated by energizing, and the magneto-optical medium 12 is arranged between the two magnetic field generating units 11.

[0041] Furthermore, the overall magnetic field strength determination system is demonstrated with a specific example. Figure 3 FIG. 1 is another structural diagram of a magnetic field strength determination system provided according to the first embodiment of the present invention. Figure 3 As shown, a magnetic field region module 1, a laser emission module 2, a signal processing module 3 and a data processing module 4, the magnetic field region module 1 includes two magnetic field generating units 11, a magneto-optical medium 12 and a displacement platform 13, the laser emission module 2 includes a laser 21 and a beam splitter prism 22, and the signal processing module 3 includes a signal amplifier 31 and a photodetector 32. The dotted line represents the propagation path of the laser beam.

[0042] Further, on the basis of the above embodiment, the laser emitting module 2 includes: a laser 21 and a beam splitter prism 22; the laser 21 is used to emit a laser beam to the beam splitter prism 22, and receive the laser signal modulated by the magnetic field region module 1, and mix it with the laser beam emitted by itself through the Brewster window in the inner cavity of the laser 21 to generate a self-mixing interference signal and emit it to the beam splitter prism 22; the beam splitter prism 22 is used to split the laser beam or the self-mixing interference signal into two coherent laser signals, wherein the laser first emits a laser beam, and the signal reflected back into the laser cavity forms a self-mixing interference signal. If the laser beam is not a linearly polarized laser beam, a polarizer can be added in front of the beam splitter prism 22 to polarize the laser beam into a polarized laser beam, and the first coherent laser signal is transmitted to the magnetic field region module 1, and the second coherent laser signal is reflected to the signal processing module 3.

[0043] The laser 21 may be a helium-neon laser 21, a semiconductor laser 21 or any other suitable laser 21. The system may use a linearly polarized helium-neon laser 21. When light is reflected back and forth between two mirrors and incident on the window at the Brewster angle, light vibrating parallel to the incident surface is not reflected but completely transmitted, while light vibrating perpendicular to the incident surface is reflected and absorbed successively, so that no oscillation occurs.

[0044] The beam splitter prism 22 is a depolarizing beam splitter prism 22, and the depolarizing beam splitter prism 22 has a beam splitting ratio of 50:50, and can split the incident light into two beams in a ratio of half transmission and half reflection. A linearly polarized laser beam can be understood as light in which the electromagnetic field vector of the light wave vibrates in a certain direction. A coherent laser signal refers to two laser beams with a fixed phase difference and frequency difference.

[0045] Specifically, the laser emitting module 2 emits a laser beam to the beam splitter prism 22 through the laser 21, and the laser beam is split into two coherent laser signals through the beam splitter side of the beam splitter prism 22. The first coherent laser signal is transmitted to the magnetic field region module 1, and the second coherent laser signal is reflected to the signal processing module 3. The light-transmitting side (i.e., the opposite side of the beam splitter side) of the beam splitter prism 22 transmits the laser signal modulated by the magnetic field region module 1. The laser 21 receives the laser signal modulated by the magnetic field region module 1, and mixes it with the laser beam emitted by itself through the Brewster window in the inner cavity of the laser 21, generates a self-mixing interference signal and emits it to the beam splitter prism 22. The beam splitter prism 22 splits the self-mixing interference signal into two coherent laser signals through the beam splitter side. The first coherent laser signal is transmitted to the magnetic field region module 1, and the second coherent laser signal is reflected to the signal processing module 3.

[0046] Furthermore, the signal processing module 3 includes: a signal amplifier 31 and a photodetector 32; the signal amplifier 31 is used to amplify the self-mixing interference signal to obtain an amplified light signal and transmit it to the photodetector 32; the photodetector 32 is used to convert the amplified light signal into an electrical signal to be detected and send it to the data processing module 4.

[0047] In this embodiment, the signal amplifier 31 can be understood as a device for enhancing the amplitude or power of a signal. The amplified optical signal can be understood as a signal enhanced by the signal amplifier 31. The photodetector 32 can be understood as a device for converting an optical signal into an electrical signal, and can also be a photodiode or any other suitable detector. The electrical signal to be detected can be understood as a signal converted into an electrical signal for determining the magnetic field strength.

[0048] Specifically, the signal processing module 3 first amplifies the self-mixing interference signal or laser signal reflected by the splitter prism 22 through the signal amplifier 31 to obtain an amplified light signal, and then receives the amplified light signal through the photodetector 32, and converts the output power of the laser into a change in the output electrical signal by detecting the intensity change of the reflected light beam, thereby obtaining the electrical signal to be detected and transmitting it to the data processing module 4.

[0049] Furthermore, the electrical signal to be detected includes a first electrical signal to be detected that has not been acted upon by a magnetic field and a second electrical signal to be detected that has been acted upon by a magnetic field, and the data processing module 4 includes:

[0050] An information acquisition unit, used to acquire a preset Verdet constant and medium length of the magneto-optical medium 12;

[0051] The magnetic field strength determination unit is used to determine the magnetic field strength of the magnetic field area according to the Verdet constant, the medium length, the first peak-to-peak value of the amplitude of the first electrical signal to be detected, and the second peak-to-peak value of the amplitude of the second electrical signal to be detected.

[0052] In this embodiment, the Verdet constant can be understood as a physical quantity that describes the optical properties of a material, which is related to the refractive index and extinction coefficient of the material. The medium length can be understood as the length of the magneto-optical medium 12. The first electrical signal to be detected can be understood as the electrical signal to be detected that passes when the magnetic field region module 1 does not generate a magnetic field region. The second electrical signal to be detected can be understood as the electrical signal to be detected that passes when the magnetic field region module 1 generates a magnetic field region.

[0053] Specifically, when receiving the electrical signal to be detected, the information acquisition unit can determine the magnetic field strength of the magnetic field area based on the Verdet constant, the medium length, the first peak-to-peak value of the amplitude of the first electrical signal to be detected, and the second peak-to-peak value of the amplitude of the second electrical signal to be detected.

[0054] For example, in the initial state where no magnetic field region is generated, the electric field E in the cavity mirror of the laser can be expressed as:

[0055]

[0056] Where l is the cavity length of the laser, E0 is the amplitude of the electric field, ω is the angular frequency, is the initial phase. c is the refractive index of the laser cavity, t is the time. K = 2π / λ is the wave vector, where λ is the wavelength of the laser.

[0057] After that, it is coupled to the inner cavity and finally detected by the photodetector after superposition. The superimposed wave is the same as the initial wave. The reflection coefficient r of the equivalent reflector can be obtained by calculation. eff :

[0058]

[0059] Among them, n c is the refractive index of the magneto-optical medium, the distance from the external cavity (i.e., the laser to the displacement platform) is L, and the displacement platform is modulated with a frequency f and an amplitude ΔL, r3 is the reflection coefficient of the reflector on the displacement platform, t a is the transmission coefficient of the magneto-optical medium due to absorption or reflection of the magneto-optical medium, t p is the transmittance of the Brewster window. M1 and M2 are two reflection surfaces inside the laser. The reflection coefficient of M2 is r2. The reflected light wave makes a round trip in the laser cavity. Then the feedback coupling coefficient is obtained. The amplitude P of the laser self-mixing signal without magnetic field effect F0 It can be expressed as:

[0060]

[0061] When a constant magnetic field is applied to both ends of the magneto-optical medium, the polarization angle of the feedback light changes by θ. Since the Faraday angle doubles in the process of light returning to the laser cavity, θ can be expressed as:

[0062] θ=2VBl s

[0063] Where V is the Verdet constant, B is the magnetic field strength, l s Indicates the length of the medium.

[0064] Then the laser output power that produces the magnetic field region effect is:

[0065]

[0066] The first peak-to-peak value ΔP of the self-mixing output power before and after the magnetic field is applied is obtained. F0 and the second peak-to-peak value ΔP FB The ratio of and the magnitude of the magnetic field have the following relationship:

[0067]

[0068] Among them, ΔP FB Indicates the second peak-to-peak value, ΔP F0 represents the first peak-to-peak value, and V represents the Verdet constant.

[0069] It follows that:

[0070]

[0071] The above formula shows the linear relationship between S and the magnetic field size B.

[0072] Wherein, the magnetic field strength determination unit is specifically used for:

[0073] According to the Verdet constant, the medium length, the first peak-to-peak value of the amplitude of the first electrical signal to be detected, and the second peak-to-peak value of the amplitude of the second electrical signal to be detected, the magnetic field intensity of the magnetic field region is determined by the following formula:

[0074]

[0075] Where B represents the magnetic field strength, ΔP FB Indicates the second peak-to-peak value, ΔP F0 represents the first peak-to-peak value, V represents the Verdet constant, l s Indicates the length of the medium.

[0076] The technical solution of the embodiment of the present invention can realize the functions of polarization and detection simultaneously through the laser, use fewer optical devices, and realize a highly compact optical system with lower cost. The sensitivity of magnetic field measurement is improved by magneto-optical medium, and it has strong anti-interference ability and can adapt to magnetic field detection in different environments. The laser interference high-precision magnetic field sensor system established based on the Faraday effect has the characteristics of system optical path design, simple structure, compactness and easy alignment, strong sensitivity, strong anti-interference ability and high precision. Then, the magnetic field strength of high-quality signals to be detected is calculated through the data processing module, which ensures the accuracy of the determination of the magnetic field strength.

[0077] For example, in order to facilitate understanding of the signal effect in the present invention, a specific example is used for demonstration. Figure 4 This is a signal example diagram of a magnetic field strength determination system provided in Embodiment 1 of the present invention, such as Figure 4 The figure shows the self-mixing signal obtained after adjusting the magnetic field, which is the result of filtering by the variational mode decomposition filtering (VMD) algorithm. According to the Faraday effect, the polarization angle of the laser beam passing through the crystal changes. Then, the light returning to the laser cavity is modulated, causing the output power of the laser to change. This partial contribution manifests itself as the envelope amplitude modulation of the electrical signal to be detected. The results show that as the magnetic field gradually increases, the envelope of the signal gradually decreases. In addition, the envelope of the power peak before and after the application of the magnetic field is approximately constant. In the figure, the amplitude is larger when the horizontal axis time is 0-2, which corresponds to the signal before the magnetic field is applied, and the corresponding amplitude is the first peak-to-peak value ΔP F0 ; After the horizontal axis time is 2, the amplitude gradually decreases and stabilizes at 3, which corresponds to the signal after the magnetic field is applied. The corresponding amplitude is the second peak-to-peak value ΔP FB .

[0078] For example, in order to facilitate understanding of the magnetic field strength determination effect of the present invention, a specific example is used for demonstration. Figure 5 : is an error example diagram of a magnetic field strength determination system provided according to the first embodiment of the present invention. The value range of the two magnetic field generating units (electromagnets in this example) in the magnetic field region module is adjusted from 0mT to different magnetic field values, with an interval of about 10mT. Each magnetic field value is measured five times, and it can be seen that the linear fit of the actual magnetic field and the measured magnetic field and the relative error are as follows Figure 5 As shown, the square mark is the magnetic field measurement value, the line with the square mark represents the linear fit, and the line with the triangle mark represents the relative error. After calculation, the Pearson parameter Pearson's r is 0.99975, and the determination coefficient (R square) is 0.99947, which shows that the measured value has a good linear fit with the actual value. In the measurement range of 0-100mT, the relative error is stable within ±1.6%. When the magnetic field continues to increase, the visibility of the self-mixing interference signal fringes will be reduced, and the noise percentage will increase relatively, affecting the experimental accuracy. Therefore, the optimal measurement range of the system is 0-100mT, and the magnetic field measurement method described in the present invention has good stability.

[0079] The above-mentioned embodiments are only preferred embodiments of the present invention and cannot be used to limit the scope of protection of the present invention. Any non-substantial changes and substitutions made by technicians in this field on the basis of the present invention shall fall within the scope of protection required by the present invention.

[0080] Embodiment 2

[0081] Figure 6 A flowchart of a method for determining magnetic field strength is provided for the first embodiment of the present invention. This embodiment is applicable to the determination of magnetic field strength. The method can be executed by a magnetic field strength determination system, and the magnetic field strength determination system can be executed by a computer device as the execution subject of each module. The system includes: a magnetic field area module, a laser emission module, a signal processing module and a data processing module. The magnetic field area module includes two magnetic field generating units, a magneto-optical medium and a displacement platform. The two magnetic field generating units are symmetrically placed according to a preset air gap, and the magneto-optical medium is set between the two magnetic field generating units.

[0082] like Figure 6 As shown, the method includes:

[0083] S610 , generating a magnetic field region to be measured between preset air gaps based on a set current using two magnetic field generating units.

[0084] S620, emitting a laser signal to the magnetic field region module through the laser emitting module, receiving the laser signal modulated by the magnetic field region module, and generating a self-mixing interference signal to reflect to the signal processing module.

[0085] S630, changing the polarization plane of the laser signal passing through the magneto-optical medium under the action of the magnetic field in the magnetic field region.

[0086] S640, generating a displacement through a displacement platform, modulating a laser signal transmitted through the magneto-optical medium through the displacement, and reflecting the laser signal modulated by the displacement back to the magneto-optical medium.

[0087] S650, receiving the laser signal modulated by the magnetic field region module through the laser emission module, and generating a self-mixing interference signal to be reflected to the signal processing module.

[0088] S660: Process the self-mixing interference signal through the signal processing module to generate an electrical signal to be detected and send it to the data processing module.

[0089] S670. Determine the magnetic field strength of the magnetic field region according to the output power of the electrical signal to be detected by the data processing module.

[0090] The technical solution of the embodiment of the present invention is to establish a magnetic field strength determination system, the system includes: a magnetic field area module, a laser emission module, a signal processing module and a data processing module, the magnetic field area module includes two magnetic field generating units, a magneto-optical medium and a displacement platform, the two magnetic field generating units are symmetrically placed according to a preset air gap, and the magneto-optical medium is set between the two magnetic field generating units. The method includes generating a magnetic field area to be measured between the preset air gaps based on a set current by two magnetic field generating units; emitting a laser signal to the magnetic field area module by the laser emission module, receiving the laser signal modulated by the magnetic field area module, and generating a self-mixing interference signal to reflect to the signal processing module; changing the polarization plane of the laser signal passing through the magneto-optical medium under the action of the magnetic field in the magnetic field area; generating a displacement by the displacement platform, modulating the laser signal transmitted by the magneto-optical medium by the displacement, and reflecting the laser signal modulated by the displacement back to the magneto-optical medium; processing the self-mixing interference signal by the signal processing module, generating an electrical signal to be detected and sending it to the data processing module; determining the magnetic field strength of the magnetic field area according to the output power of the electrical signal to be detected by the data processing module. The anti-interference ability of the system is determined by the magnetic field strength, and a higher quality signal to be detected is obtained. The magnetic field strength is then calculated by the signal to be detected, thereby ensuring the accuracy of the determination of the magnetic field strength.

[0091] Embodiment 3

[0092] Figure 7 A schematic diagram of a computer device 70 that can be used to implement an embodiment of the present invention is shown. The computer device is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The computer device can also represent various forms of mobile devices, such as personal digital processing, cellular phones, smart phones, wearable devices (such as helmets, glasses, watches, etc.) and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely examples and are not intended to limit the implementation of the present invention described and / or required herein.

[0093] like Figure 7As shown, the computer device 70 includes at least one processor 71, and a memory connected to the at least one processor 71, such as a read-only memory (ROM) 72, a random access memory (RAM) 77, etc., wherein the memory stores a computer program that can be executed by at least one processor, and the processor 71 can perform various appropriate actions and processes according to the computer program stored in the read-only memory (ROM) 72 or the computer program loaded from the storage unit 78 to the random access memory (RAM) 73. In the RAM 73, various programs and data required for the operation of the computer device 70 can also be stored. The processor 71, the ROM 72, and the RAM 73 are connected to each other via a bus 74. An input / output (I / O) interface 75 is also connected to the bus 74.

[0094] A number of components in the computer device 70 are connected to the I / O interface 75, including: an input unit 76, such as a keyboard, a mouse, etc.; an output unit 77, such as various types of displays, speakers, etc.; a storage unit 78, such as a disk, an optical disk, etc.; and a communication unit 79, such as a network card, a modem, a wireless communication transceiver, etc. The communication unit 79 allows the computer device 70 to exchange information / data with other devices through a computer network such as the Internet and / or various telecommunication networks.

[0095] The processor 71 may be a variety of general and / or special processing components with processing and computing capabilities. Some examples of the processor 71 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various special artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, a digital signal processor (DSP), and any appropriate processor, controller, microcontroller, etc. The processor 71 performs the various methods and processes described above, such as a magnetic field strength determination method.

[0096] In some embodiments, the magnetic field strength determination method may be implemented as a computer program, which is tangibly contained in a computer-readable storage medium, such as a storage unit 78. In some embodiments, part or all of the computer program may be loaded and / or installed on the computer device 70 via the ROM 72 and / or the communication unit 79. When the computer program is loaded into the RAM 73 and executed by the processor 71, one or more steps of the magnetic field strength determination method described above may be performed. Alternatively, in other embodiments, the processor 71 may be configured to perform the magnetic field strength determination method in any other suitable manner (e.g., by means of firmware).

[0097] Various implementations of the systems and techniques described above herein can be implemented in digital electronic circuit systems, integrated circuit systems, field programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), application specific standard products (ASSPs), systems on chips (SOCs), load programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various implementations can include: being implemented in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which can be a special purpose or general purpose programmable processor that can receive data and instructions from a storage system, at least one input device, and at least one output device, and transmit data and instructions to the storage system, the at least one input device, and the at least one output device.

[0098] Computer programs for implementing the methods of the present invention may be written in any combination of one or more programming languages. These computer programs may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, so that when the computer program is executed by the processor, the functions / operations specified in the flow chart and / or block diagram are implemented. The computer program may be executed entirely on the machine, partially on the machine, partially on the machine and partially on a remote machine as a stand-alone software package, or entirely on a remote machine or server.

[0099] In the context of the present invention, a computer-readable storage medium may be a tangible medium that may contain or store a computer program for use by or in combination with an instruction execution system, device or equipment. A computer-readable storage medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices or equipment, or any suitable combination of the foregoing. Alternatively, a computer-readable storage medium may be a machine-readable signal medium. A more specific example of a machine-readable storage medium may include an electrical connection based on one or more lines, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0100] To provide interaction with a user, the systems and techniques described herein can be implemented on a computer device having: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to the user; and a keyboard and a pointing device (e.g., a mouse or trackball) through which the user can provide input to the computer device. Other types of devices can also be used to provide interaction with the user; for example, the feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user can be received in any form (including acoustic input, voice input, or tactile input).

[0101] The systems and techniques described herein may be implemented in a computing system that includes backend components (e.g., as a data server), or a computing system that includes middleware components (e.g., an application server), or a computing system that includes frontend components (e.g., a user computer with a graphical user interface or a web browser through which a user can interact with implementations of the systems and techniques described herein), or a computing system that includes any combination of such backend components, middleware components, or frontend components. The components of the system may be interconnected by any form or medium of digital data communication (e.g., a communication network). Examples of communication networks include: a local area network (LAN), a wide area network (WAN), a blockchain network, and the Internet.

[0102] A computing system may include a client and a server. The client and the server are generally remote from each other and usually interact through a communication network. The client and server relationship is generated by computer programs running on the corresponding computers and having a client-server relationship with each other. The server may be a cloud server, also known as a cloud computing server or cloud host, which is a host product in the cloud computing service system to solve the defects of difficult management and weak business scalability in traditional physical hosts and VPS services.

[0103] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps described in the present invention can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solution of the present invention can be achieved, and this document does not limit this.

[0104] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A magnetic field strength determination system, characterized in that: The system comprises: a magnetic field region module, a laser emission module, a signal processing module and a data processing module, wherein the magnetic field region module comprises two magnetic field generating units, a magneto-optical medium and a displacement platform, wherein the two magnetic field generating units are symmetrically placed according to a preset air gap, and the magneto-optical medium is arranged between the two magnetic field generating units; The two magnetic field generating units are used to generate a magnetic field region to be measured between a preset air gap based on a set current; The laser emitting module is used to emit a laser signal to the magnetic field region module, receive the laser signal modulated by the magnetic field region module, and generate a self-mixed interference signal to be reflected to the signal processing module; The magneto-optical medium is used to change the polarization plane of the laser signal passing through under the action of the magnetic field of the magnetic field region; The displacement platform is used to generate a displacement, modulate the laser signal transmitted by the magneto-optical medium by the displacement, and reflect the laser signal modulated by the displacement back to the magneto-optical medium; The signal processing module is used to process the self-mixing interference signal, generate an electrical signal to be detected and send it to the data processing module; The data processing module is used to determine the magnetic field strength of the magnetic field area according to the output power of the electrical signal to be detected.

2. The system according to claim 1, characterized in that The laser emitting module comprises: a laser and a beam splitter prism; The laser is used to emit a laser beam to the beam splitter prism, receive the laser signal modulated by the magnetic field region module, and mix it with the laser beam emitted by itself through the Brewster window in the laser cavity to generate a self-mixing interference signal and emit it to the beam splitter prism; The beam splitter prism is used to split the laser beam or the self-mixing interference signal into two coherent laser signals, the first coherent laser signal is transmitted to the magnetic field region module, and the second coherent laser signal is reflected to the signal processing module.

3. The system according to claim 2, characterized in that The beam splitter prism is a depolarizing beam splitter prism, and the beam splitting ratio of the depolarizing beam splitter prism is 50:

50.

4. The system according to claim 1, characterized in that The signal processing module includes: a signal amplifier and a photoelectric detector; The signal amplifier is used to amplify the self-mixing interference signal to obtain an amplified optical signal and transmit it to the photoelectric detector; The photoelectric detector is used to convert the amplified optical signal into an electrical signal to be detected and send it to the data processing module.

5. The system according to claim 1, characterized in that The magneto-optical medium is terbium gallium garnet crystal.

6. The system according to claim 1, characterized in that The electrical signal to be detected includes a first electrical signal to be detected that has not been acted upon by a magnetic field and a second electrical signal to be detected that has been acted upon by a magnetic field, and the data processing module includes: An information acquisition unit, used for acquiring a preset Verdet constant and a medium length of the magneto-optical medium; The magnetic field strength determination unit is used to determine the magnetic field strength of the magnetic field area according to the Verdet constant, the medium length, the first peak-to-peak value of the amplitude of the first electrical signal to be detected, and the second peak-to-peak value of the amplitude of the second electrical signal to be detected.

7. The system according to claim 1, characterized in that The magnetic field strength determination unit is specifically used for: According to the Verdet constant, the medium length, the first peak-to-peak value of the amplitude of the first electrical signal to be detected, and the second peak-to-peak value of the amplitude of the second electrical signal to be detected, the magnetic field intensity of the magnetic field region is determined by the following formula: Where B represents the magnetic field strength, ΔP FB Indicates the second peak-to-peak value, ΔP F0 represents the first peak-to-peak value, V represents the Verdet constant, l s Indicates the length of the medium.

8. A method for determining magnetic field strength, characterized in that: The method is applied to a magnetic field strength determination system according to any one of claims 1 to 7, the system comprising: a magnetic field region module, a laser emission module, a signal processing module and a data processing module, the magnetic field region module comprising two magnetic field generating units, a magneto-optical medium and a displacement platform, the two magnetic field generating units are symmetrically placed according to a preset air gap, the magneto-optical medium is arranged between the two magnetic field generating units, the method comprising: generating a magnetic field region to be measured between the preset air gaps by using the two magnetic field generating units based on a set current; The laser emitting module emits a laser signal to the magnetic field region module, receives the laser signal modulated by the magnetic field region module, and generates a self-mixed interference signal to be reflected to the signal processing module; The magneto-optical medium changes the polarization plane of the laser signal passing through the magneto-optical medium under the action of the magnetic field in the magnetic field region; Generate a displacement through the displacement platform, modulate the laser signal transmitted by the magneto-optical medium through the displacement, and reflect the laser signal modulated by the displacement back to the magneto-optical medium; Processing the self-mixing interference signal through the signal processing module to generate an electrical signal to be detected and sending it to the data processing module; The magnetic field strength of the magnetic field area is determined by the data processing module according to the output power of the electrical signal to be detected.

9. A computer device, characterized in that: The computer device is used as the execution subject of each module in the magnetic field strength determination system according to any one of claims 1 to 7, including: at least one processor; and a memory communicatively connected to the at least one processor; wherein, The memory stores a computer program executable by the at least one processor, and the computer program is executed by the at least one processor so that the at least one processor can perform the magnetic field strength determination method according to claim 8.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a processor to implement the method for determining the magnetic field strength of claim 8 when executed.

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