A magnetic detection device

Abstract

The present invention discloses a magnetic detection device, which belongs to the technical field of magneto-optical Kerr effect detection and is used to solve the technical problem that the polar and longitudinal detection results of existing magneto-optical Kerr effect detection devices are difficult to match with the detection position. The device includes a first polarized light source, a first beam splitter, a lens assembly, a first analyzer, and a first photoelectric sensor; a second polarized light source, a second analyzer, and a second photoelectric sensor; first polarized light emitted from the first polarized light source passes through the first beam splitter and vertically enters the measured position of the measured object through a first optical path channel, and the first polarized light reflected by the measured object passes through the first optical path channel and the first analyzer to irradiate the first photoelectric sensor; second polarized light emitted from the second polarized light source passes through the second optical path channel and the second analyzer to irradiate the second photoelectric sensor.

Description

Technical Field

[0001] The present invention relates to the technical field of magneto-optical Kerr effect detection, and in particular to a magnetic detection device. Background Art

[0002] The magneto-optical Kerr effect means that reflected light will change due to the magnetization state of the reflective medium. Therefore, the magnetism of the object being measured can be obtained by detecting the reflected light on the surface of the object being measured. On this basis, magnetic detection equipment based on the magneto-optical Kerr effect emits polarized light to the object being measured, measures the polarization state of the reflected light from the object being measured, and thus measures the magnetism of the surface of the object being measured. In some cases, depending on the magnetic state of the object being measured, it is necessary to choose to use the polarimetric magneto-optical Kerr effect or the longitudinal magneto-optical Kerr effect to detect the object being measured. The polarimetric magneto-optical Kerr effect requires that the incident light be irradiated perpendicularly to the object being measured in order to obtain a better detection effect. The longitudinal Kerr effect requires that the incident light be irradiated obliquely to the object being measured and that the incident plane of the incident light be parallel to the direction of the magnetic domain being measured in order to obtain a better detection effect.

[0003] Existing magnetic detection devices based on the magneto-optical Kerr effect require two sets of optical paths when detecting the polar and longitudinal magneto-optical Kerr effects. It is difficult for the two sets of optical paths to be aligned at the same position, making it difficult to match the detection positions of the polar and longitudinal detection results. Summary of the Invention

[0004] An embodiment of the present invention provides a magnetic detection device for solving the following technical problem: it is difficult to match the detection positions of the polar and longitudinal detection results obtained by the existing magneto-optical Kerr detection device.

[0005] The embodiment of the present invention adopts the following technical solutions:

[0006] In one aspect, an embodiment of the present invention provides a magnetic detection device, comprising: a first polarized light source, a first beam splitter, a lens assembly, a first analyzer, and a first photoelectric sensor; a second polarized light source, a second analyzer, and a second photoelectric sensor;

[0007] The lens assembly is provided with a first optical path channel along the axial direction, and the lens assembly is symmetrically provided with a second optical path channel along the axial direction;

[0008] The first polarized light emitted from the first polarized light source passes through the first beam splitter and vertically enters the measured position of the object to be measured from the first optical path channel. The first polarized light reflected by the object to be measured passes through the first optical path channel and the first analyzer and is irradiated to the first photoelectric sensor.

[0009] The second polarized light emitted from the second polarized light source enters the measured position of the measured object along a preset inclination angle through the second optical path channel, and the second polarized light reflected by the measured object passes through the second optical path channel and the second analyzer and is irradiated to the second photoelectric sensor.

[0010] In a feasible embodiment, a reflective element is provided in the second optical path channel, and the second polarized light emitted from the second polarized light source is reflected by the reflective element and then enters the object to be measured along a preset inclination angle. The second polarized light reflected by the object to be measured is reflected by the reflective element and then irradiated to the second photoelectric sensor through the second polarizer.

[0011] In a feasible implementation manner, it is characterized in that: the reflective element is a plane mirror or a curved mirror.

[0012] In a feasible implementation, a lens element is provided in the first optical path, and the measured position of the object to be measured is located at the focus of the lens element.

[0013] In a feasible embodiment, a lens element is provided in the first optical path channel, the second photoelectric sensor is an imaging device, and the first polarized light reflected by the object to be measured passes through the lens element and forms an image on the photosensitive surface of the imaging device.

[0014] In a feasible embodiment, the device further includes: a plurality of excitation devices arranged within a preset distance from the object to be measured; the excitation devices are used to generate a magnetic field to act on the object to be measured.

[0015] In a feasible embodiment, the device further includes: a light beam guiding component, through which the second polarized light emitted from the second polarized light source enters the second optical path channel.

[0016] In a feasible embodiment, two second polarized light sources are provided, and two second photoelectric sensors are provided. The two second polarized light sources respectively emit second polarized light, and the two beams of second polarized light are respectively incident on the second optical path channel symmetrically along the axis of the lens assembly; the two beams of second polarized light reflected by the object to be measured are respectively incident on the corresponding second photoelectric sensors.

[0017] In a feasible embodiment, the device also includes a second spectrometer, and the second polarized light emitted from the second polarized light source enters the second optical path channel after at least passing through the second spectrometer; the second polarized light reflected by the object to be measured is irradiated to the second photoelectric sensor after at least passing through the second spectrometer.

[0018] In a feasible embodiment, two second beam splitters are provided, and the two beams of second polarized light are configured to pass through at least one of the second beam splitters to enter the object to be measured, and the second polarized light reflected by the object to be measured passes through at least the other of the second beam splitters to enter the photoelectric sensor.

[0019] Compared with the prior art, the magnetic detection device provided by the embodiment of the present invention has the following beneficial effects:

[0020] The magnetic detection device provided by an embodiment of the present invention incorporates two optical paths within a single device. One optical path can generate polarized light perpendicular to the object being measured to detect the polar magneto-optical Kerr effect, while the other optical path can simultaneously generate two beams of polarized light obliquely directed at the object being measured to detect the longitudinal magneto-optical Kerr effect. Furthermore, the two optical paths can be aligned with the same position on the object being measured, thereby simultaneously acquiring both polar magneto-optical Kerr effect and longitudinal magneto-optical Kerr effect detection results for the same detection position. This eliminates the need for optical path adjustment or position calibration. This reduces optical path costs while also improving detection accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments described in the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0022] Figure 1 A schematic structural diagram of a magnetic detection device provided in an embodiment of the present invention;

[0023] Figure 2 A schematic structural diagram of a magnetic detection device using another optical path design provided by an embodiment of the present invention;

[0024] Figure 3 A schematic structural diagram of a magnetic detection device including a second spectrometer provided in an embodiment of the present invention.

[0025] Description of reference numerals:

[0026] 1. First light source; 2. First polarizer; 3. First analyzer; 4. First photoelectric sensor; 5. First spectroscope; 6. Lens assembly; 7. Excitation device; 8. Object to be measured; 9. Second light source; 10. Second polarizer; 11. Second spectroscope; 12. Second analyzer; 13. Second photoelectric sensor; 14. Beam guiding assembly. DETAILED DESCRIPTION

[0027] In order to enable those skilled in the art to better understand the technical solutions of the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of this specification, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0028] An embodiment of the present invention provides a magnetic detection device, Figure 1 A schematic structural diagram of a magnetic detection device provided in an embodiment of the present invention is shown in FIG. Figure 1 As shown, the magnetic detection device at least includes: a first polarized light source, a first beam splitter 5, a lens assembly 6, a first analyzer 3, a first photoelectric sensor 4; a second polarized light source, a second analyzer 12, and a second photoelectric sensor 13.

[0029] The first polarized light source is composed of a first light source 1 and a first polarizer 2. The second polarized light source is composed of a second light source 9 and a second polarizer 10. The polarized light source is used to emit polarized detection light.

[0030] The lens assembly 6 is provided with a first optical path channel along the axial direction, and the lens assembly 6 is symmetrically provided with a second optical path channel along the axial direction.

[0031] Lens elements are installed in the lens assembly 6 in the first optical path. First polarized light emitted from the first polarized light source passes through the first beam splitter 5 and vertically incident on the measured position of the object 8 through the first optical path. The first polarized light reflected by the object 8 passes through the first optical path and the first analyzer 3 and illuminates the first photosensor 4. The first light source 1, first polarizer 2, first beam splitter 5, and lens elements form the first incident optical path of the object 8. The lens elements, first beam splitter 5, first analyzer 3, and first photosensor 4 form the first outgoing optical path of the object 8.

[0032] In one embodiment, the measured position of the object 8 is located at the focal point of the lens element. Therefore, the first polarized light passes through the lens element and converges at the measured position of the object, thereby detecting the poloidal magneto-optical Kerr effect at the measured position and, in turn, detecting the poloidal magnetism at the measured position. In this case, the first photosensor can be a photodetector, a balanced optical detector, a four-quadrant detector, an imaging device, or the like, as long as it can convert a light intensity signal into an electrical signal.

[0033] In another embodiment, the first photosensor is an imaging device. The first polarized light reflected by the object being measured passes through a lens element and forms an image on a photosensitive surface of the imaging device, thereby imaging magnetic domains within a predetermined range around the measured location. The imaging device can be a camera, a photosensitive array, or other imaging device, and typically includes a photosensitive surface for converting light intensity signals into electrical signals.

[0034] Furthermore, the second polarized light emitted from the second polarized light source passes through the second optical path channels on both sides of the lens assembly 6 and is incident on the measured position of the object to be measured 8 along a preset inclination angle. The second polarized light reflected by the object to be measured 8 passes through the second optical path channel and the second polarizer 12 and is irradiated to the second photoelectric sensor 13.

[0035] A reflective element is provided in the second optical path channel. After the second polarized light emitted from the second polarized light source reaches the second optical path channel on both sides of the lens assembly 6, it is reflected by the reflective element and incident on the object to be measured 8 along a preset inclination angle. The second polarized light reflected by the object to be measured 8 is reflected by the reflective element of the second optical path channel and then irradiated to the second photoelectric sensor 13 through the second polarizer 12.

[0036] As a feasible embodiment, the reflective element is a plane mirror or a curved mirror. The plane mirror can reflect the incident light perpendicularly incident into the second optical path onto the object under test 8 and focus it on the object under test 8 in cooperation with other optical components. The curved mirror can also be used to reflect the incident light perpendicularly incident into the second optical path at an angle onto the object under test 8, where it is focused at the measured position.

[0037] Furthermore, the device also includes a beam guiding component 14, such as Figure 1 As shown, the beam guide assembly 14 includes a plurality of reflectors at predetermined positions and predetermined tilt angles. The second polarized light emitted from the second polarized light source is reflected by the reflectors in different directions in the beam guide assembly 14 and then incident on the object under test along the second optical path of the lens assembly 6.

[0038] In some cases, two second polarized light sources and two second photosensors are provided. The two second polarized light sources each emit second polarized light. The two second detection light beams are incident on the second optical path symmetrically along the axis of the lens assembly. Accordingly, they can be incident on the measured position of the object at an angle from both sides. The two second detection light beams reflected by the object are incident on the corresponding second photosensors, and two longitudinal magneto-optical Kerr signals can be obtained through analysis, thereby reducing noise signals and enhancing the detection accuracy of in-plane magnetism.

[0039] As a feasible implementation method, Figure 2 A schematic structural diagram of a magnetic detection device using another optical path design provided in an embodiment of the present invention is shown in FIG. Figure 2As shown, the magnetic detection device provided by the present invention can also have another optical path configuration. A second light source 9 is provided, and the second polarized light emitted by the light source passes through a second polarizer 10 and is incident on a second optical path, where it is obliquely incident on the object under test 8. The second polarized light reflected by the object under test 8 is emitted through another second optical path, passes through a second analyzer 12, and is incident on a second photosensor 13. Figure 2 The light path setup shown is similar to Figure 1 Although the optical path structures of the optical path settings shown are different, the design concepts are consistent. Users can flexibly select an optical path structure for magnetic detection according to actual conditions.

[0040] In some cases, based on Figure 2 The magnetic detection device structure shown in FIG. 1 may further include a second spectroscope 11, such as Figure 3 As shown, the second polarized light emitted from the second polarized light source enters the second optical path through at least the second beam splitter 11 , and the second polarized light reflected by the object 8 is irradiated to the second photoelectric sensor 13 through at least the second beam splitter 11 .

[0041] As a feasible implementation, in some cases, two beams of second polarized light symmetrically incident on the object 8 are present in the second optical path. The second polarized light incident on the object 8 in the left second optical path will be reflected by the object 8 and then emitted from the right second optical path. At this time, there is also second polarized light incident on the right second optical path, resulting in a shared optical path. Therefore, a second beam splitter 11 is provided in the path of the second polarized light to separate the two beams sharing the same optical path.

[0042] See also Figure 1 、 Figure 3 , showing two different forms of light paths, where Figure 1 In the illustrated embodiment, a second beam splitter 11 is provided, and both the incident light path and the reflected light path of the second polarized light pass through the same second beam splitter 11; Figure 3 In the illustrated embodiment, two second beam splitters 11 are provided, and the incident light path and the reflected light path of the second polarized light pass through different second beam splitters 11 .

[0043] like Figure 1 As shown, the second light source 9, the second polarizer 10, the second beam splitter 11, the beam guide assembly 14, and the lens assembly 6 form a second incident light path of the object 8. The lens assembly 6, the beam guide assembly 14, the second beam splitter 11, the second analyzer 12, and the second photoelectric sensor 13 form a second outgoing light path of the object 8.

[0044] The beam guide assembly 14 uses multiple reflectors to adjust the direction of the second polarized light, aligning it with the second optical paths on either side of the lens assembly 6. After passing through the second optical paths, the second polarized light is focused at a preset angle onto the object under test 8. Light reflected from the object under test 8 then returns to the beam guide assembly 14 through the second optical paths in the lens assembly 6. After being guided by the beam guide assembly 14, it reaches the second analyzer 12 and finally enters the second photosensor 13.

[0045] Furthermore, the device further comprises: a plurality of excitation devices arranged within a preset distance from the object to be measured, wherein the excitation devices are used to generate a magnetic field to act on the object to be measured.

[0046] The magnetic detection device provided by an embodiment of the present invention incorporates two optical paths within a single device. One optical path can generate polarized light perpendicular to the object being measured to detect the polar magneto-optical Kerr effect, while the other optical path can simultaneously generate two beams of polarized light obliquely directed at the object being measured to detect the longitudinal magneto-optical Kerr effect. Furthermore, the two optical paths can be aligned with the same position on the object being measured, thereby simultaneously acquiring both polar magneto-optical Kerr effect and longitudinal magneto-optical Kerr effect detection results for the same detection position. This eliminates the need for optical path adjustment or position calibration. This reduces optical path costs while also improving detection accuracy.

[0047] It should also be noted that the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, commodity, or apparatus that includes a series of elements includes not only those elements but also other elements not explicitly listed, or includes elements inherent to such process, method, commodity, or apparatus. In the absence of further limitations, an element defined by the phrase "comprises a ..." does not exclude the presence of other identical elements in the process, method, commodity, or apparatus that includes the element.

[0048] This specification may be described in the general context of computer-executable instructions, such as program modules, executed by a computer. Generally, program modules include routines, programs, objects, components, data structures, and the like that perform specific tasks or implement specific abstract data types. This specification may also be practiced in distributed computing environments where tasks are performed by remote processing devices connected through a communications network. In a distributed computing environment, program modules may be located in both local and remote computer storage media, including storage devices.

[0049] The various embodiments of the present invention are described in a progressive manner. Similar portions between the various embodiments can be referenced to each other, and each embodiment focuses on the differences from the other embodiments. In particular, the device, apparatus, and non-volatile computer storage medium embodiments are generally similar to the method embodiments, so their descriptions are simplified. For relevant details, refer to the descriptions of the method embodiments.

[0050] The above description of specific embodiments of the present invention is provided. In addition, the processes depicted in the accompanying drawings do not necessarily require the specific order or sequential order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0051] The foregoing is merely an embodiment of the present invention and is not intended to limit the present invention. It will be apparent to those skilled in the art that various modifications and variations may be made to the embodiments of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the embodiments of the present invention are intended to be included within the scope of protection of the present invention.

Claims

1. A magnetic detection device, characterized in that: The device comprises: A first polarized light source, a first beam splitter, a lens assembly, a first analyzer, and a first photoelectric sensor; a second polarized light source, a second analyzer, and a second photoelectric sensor; The lens assembly is provided with a first optical path channel along the axial direction, and the lens assembly is symmetrically provided with a second optical path channel along the axial direction; A reflective element is provided in the second optical path channel. The second polarized light emitted from the second polarized light source is reflected by the reflective element and then incident on the object to be measured along a preset inclination angle. The second polarized light reflected by the object to be measured is reflected by the reflective element and then irradiated to the second photoelectric sensor through the second analyzer. The reflective element is a plane mirror or a curved mirror. The first polarized light emitted from the first polarized light source passes through the first beam splitter and vertically enters the measured position of the object to be measured from the first optical path channel. The first polarized light reflected by the object to be measured passes through the first optical path channel and the first analyzer and is irradiated to the first photoelectric sensor. The second polarized light emitted from the second polarized light source passes through the second optical path and is incident on the measured position of the object at a preset angle. The second polarized light reflected by the object passes through the second optical path and the second analyzer and is irradiated to the second photoelectric sensor. Two second polarized light sources are provided, and two second photoelectric sensors are provided. The two second polarized light sources respectively emit second polarized light, and the two second polarized light beams are incident on the second optical path symmetrically along the axis of the lens assembly; the two second polarized light beams reflected by the object to be measured respectively enter the corresponding second photoelectric sensor; The second polarized light incident on the object under test in the left second optical path channel will be emitted from the right second optical path channel after being reflected by the object under test. The second polarized light is also incident on the right second optical path channel. A second beam splitter is provided in the path of the second polarized light to separate the two beams of light shared by the optical path. The two beams of second polarized light reflected by the object to be measured are incident on the corresponding second photoelectric sensors respectively, and two longitudinal magneto-optical Kerr signals can be obtained by analysis, thereby reducing the noise signal and enhancing the detection accuracy of the in-plane magnetism.

2. A magnetic detection device according to claim 1, characterized in that: A lens element is provided in the first optical path, and the measured position of the object to be measured is located at the focus of the lens element.

3. A magnetic detection device according to claim 1, characterized in that: A lens element is provided in the first optical path, and the second photoelectric sensor is an imaging device. The first polarized light reflected by the object to be measured passes through the lens element and forms an image on the photosensitive surface of the imaging device.

4. A magnetic detection device according to claim 1, characterized in that: The device further comprises: a plurality of excitation devices arranged within a preset distance from the object to be measured; the excitation devices are used to generate a magnetic field to act on the object to be measured.

5. The magnetic detection device according to claim 1, characterized in that: The device further includes a light beam guiding component, through which the second polarized light emitted from the second polarized light source enters the second optical path channel.

6. The magnetic detection device according to claim 1, characterized in that: The device also includes a second beam splitter, and the second polarized light emitted from the second polarized light source enters the second optical path after at least passing through the second beam splitter; the second polarized light reflected by the object to be measured is irradiated to the second photoelectric sensor after at least passing through the second beam splitter.

7. A magnetic detection device according to claim 6, characterized in that: Two second beam splitters are provided, and the two second polarized light beams are configured to enter the object under test through at least one of the second beam splitters, and the second polarized light reflected by the object under test enters the photoelectric sensor through at least the other of the second beam splitters.

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