Magnetic detection device

Abstract

The invention discloses a magnetic detection device, belongs to the technical field of magneto-optical Kerr effect detection, and is used for solving the technical problem that polar and longitudinal detection results detected by an existing magneto-optical Kerr detection device are difficult to match detection positions. The device comprises a first polarized light source, a first spectroscope, a lens assembly, a first polarization analyzer and a first photoelectric sensor. A second polarization light source, a second analyzer and a second photoelectric sensor; first polarized light emitted from a first polarized light source vertically enters a measured position of a measured object from a first light path channel through a first spectroscope, and the first polarized light reflected by the measured object irradiates a first photoelectric sensor through the first light path channel and a first polarization analyzer; second polarized light emitted from the second polarized light source enters the measured object through the second light path channel along the preset inclination angle, and the second polarized light reflected by the measured object passes through the second light path channel and the second polarization analyzer and irradiates 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 refers to the fact that the reflected light will change due to the magnetization state of the reflecting medium. Therefore, the magnetism of the object to be measured can be obtained by detecting the reflected light on the surface of the object to be measured. On this basis, a magnetic detection device based on the magneto - optical Kerr effect emits polarized light to the object to be measured and measures the polarization state of the reflected light of the object to be measured, thereby measuring the magnetism on the surface of the object to be measured. In some cases, for the magnetic state of the object to be measured, it is necessary to select to use the polar magneto - optical Kerr effect or the longitudinal magneto - optical Kerr effect to detect the object to be measured. The polar magneto - optical Kerr effect requires the incident light to be perpendicularly incident on the object to be measured to obtain a better detection effect. The longitudinal Kerr effect requires the incident light to be obliquely incident on the object to be measured and requires the incident plane of the incident light to be parallel to the direction of the measured magnetic domain to obtain a better detection effect.

[0003] When the existing magnetic detection devices based on the magneto - optical Kerr effect detect the polar and longitudinal magneto - optical Kerr effects, two sets of optical paths need to be set up. It is difficult to align the two sets of optical paths at the same position, resulting in difficulty in matching the detection positions of the polar and longitudinal detection results. Summary of the Invention

[0004] The embodiments of the present invention provide a magnetic detection device to solve the following technical problem: it is difficult to match the detection positions of the polar and longitudinal detection results detected by the existing magneto - optical Kerr detection device.

[0005] The embodiments of the present invention adopt the following technical solutions: On the one hand, the embodiments of the present invention provide a magnetic detection device, which includes: a first polarized light source, a first beam splitter, a lens assembly, a first analyzer, a first photoelectric sensor; a second polarized light source, a second analyzer, a second photoelectric sensor; The lens assembly is axially provided with a first optical path channel, and the lens assembly is axially symmetrically provided with a second optical path channel; The first polarized light emitted from the first polarized light source passes through the first beam splitter and perpendicularly enters the measured position of the object to be measured through the first optical path channel. The first polarized light reflected by the object to be measured passes through the first optical path channel, the first analyzer and is irradiated onto the first photoelectric sensor; The second polarized light emitted from the second polarized light source enters the measured position of the object to be measured through the second optical path channel at a preset inclination angle. The second polarized light reflected by the object to be measured passes through the second optical path channel, the second analyzer and is irradiated onto the second photoelectric sensor.

[0006] In a feasible implementation, a reflecting element is provided in the second optical path channel. The second polarized light emitted from the second polarized light source is reflected by the reflecting element and then incident on the object to be measured at a preset inclination angle. The second polarized light reflected by the object to be measured is reflected by the reflecting element and then irradiated onto the second photoelectric sensor through the second analyzer.

[0007] In a feasible implementation, it is characterized in that: the reflecting element is a plane mirror or a curved mirror.

[0008] In a feasible implementation, a lens element is provided in the first optical path channel, and the measured position of the object to be measured is located at the focal point of the lens element.

[0009] In a feasible implementation, 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.

[0010] In a feasible implementation, 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 acting on the object to be measured.

[0011] In a feasible implementation, the device further includes: a beam guiding assembly, and the second polarized light emitted from the second polarized light source is incident on the second optical path channel through the beam guiding assembly.

[0012] In a feasible implementation, there are two second polarized light sources, 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 axially symmetrically along 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.

[0013] In a feasible implementation, the device further includes a second beam splitter, and the second polarized light emitted from the second polarized light source enters the second optical path channel after passing through at least the second beam splitter; the second polarized light reflected by the object to be measured is irradiated onto the second photoelectric sensor after passing through at least the second beam splitter.

[0014] In a feasible implementation, there are two second beam splitters, and the two beams of second polarized light are configured to be incident on the object to be measured after passing through at least one of the second beam splitters, and the second polarized light reflected by the object to be measured is incident on the photoelectric sensor after passing through at least the other of the second beam splitters.

[0015] Compared with the prior art, a magnetic detection device provided by an embodiment of the present invention has the following beneficial effects: The magnetic detection device provided by the embodiment of the present invention sets two optical paths in one device. It can generate polarized light that perpendicularly irradiates the object to be measured through one optical path to detect the polar magneto-optic Kerr effect, and at the same time generate two polarized lights that obliquely irradiate the object to be measured through the other optical path to detect the longitudinal magneto-optic Kerr effect. And the two optical paths can be aligned with the same position of the object to be measured, so as to simultaneously obtain the detection results of the polar magneto-optic Kerr effect and the longitudinal magneto-optic Kerr effect at the same detection position, without adjusting the optical path and without calibrating the position. This not only reduces the cost of the optical path, but also improves the detection accuracy. Description of the Drawings

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments recorded in the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings. In the drawings: Figure 1 It is a schematic structural diagram of a magnetic detection device provided by an embodiment of the present invention; Figure 2 It is a schematic structural diagram of a magnetic detection device with another optical path design provided by an embodiment of the present invention; Figure 3 It is a schematic structural diagram of a magnetic detection device including a second beam splitter provided by an embodiment of the present invention.

[0017] Description of the Reference Numerals: 1. First light source; 2. First polarizer; 3. First analyzer; 4. First photoelectric sensor; 5. First beam splitter; 6. Lens assembly; 7. Excitation device; 8. Object to be measured; 9. Second light source; 10. Second polarizer; 11. Second beam splitter; 12. Second analyzer; 13. Second photoelectric sensor; 14. Beam guiding assembly. Detailed Embodiments

[0018] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of this specification, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0019] The embodiment of the present invention provides a magnetic detection device, Figure 1Schematic structural diagram of a magnetic detection device provided by an embodiment of the present invention, as Figure 1 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.

[0020] Among them, 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 function of the polarized light source is to emit polarized detection light.

[0021] The lens assembly 6 is axially provided with a first optical path channel, and the lens assembly 6 is axially symmetrically provided with a second optical path channel.

[0022] A lens element is provided in the lens assembly 6 in the first optical path channel. The first polarized light emitted from the first polarized light source passes through the first beam splitter 5 and vertically enters the measured position of the object to be measured 8 through the first optical path channel. The first polarized light reflected by the object to be measured 8 passes through the first optical path channel, the first analyzer 3 and irradiates the first photoelectric sensor 4. The first incident optical path of the object to be measured 8 is composed of the first light source 1, the first polarizer 2, the first beam splitter 5 and the lens element. The first exit optical path of the object to be measured 8 is composed of the lens element, the first beam splitter 5, the first analyzer 3 and the first photoelectric sensor 4.

[0023] In one embodiment, the measured position of the object to be measured 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 to be measured, so as to detect the polar magneto-optical Kerr effect at the measured position, and then detect the magnetism in the polar direction of the measured position. In this case, for the first photoelectric sensor, it can be a photodetector, a balanced optical detector, a quadrant detector, an imaging device, etc., as long as it can convert the light intensity signal into an electrical signal.

[0024] In another embodiment, the first 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 to image the magnetic domains within a preset range around the measured position. For the imaging device, it can be a camera, a photosensitive array or other devices capable of imaging, and usually a photosensitive surface is provided to convert the light intensity signal into an electrical signal.

[0025] Further, 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 enters the measured position of the object to be measured 8 at a preset inclination angle. The second polarized light reflected by the object to be measured 8 passes through the second optical path channel, the second analyzer 12 and irradiates the second photoelectric sensor 13.

[0026] A reflection 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 channels on both sides of the lens assembly 6, it is reflected by the reflection element and incident on the object to be measured 8 at a preset inclination angle. The second polarized light reflected by the object to be measured 8 is reflected by the reflection element in the second optical path channel and then irradiated to the second photoelectric sensor 13 through the second analyzer 12.

[0027] As a feasible implementation, the reflection element is a plane mirror or a curved mirror. The plane mirror can reflect the incident light vertically incident into the second optical path channel onto the object to be measured 8 and focus on the object to be measured 8 with the cooperation of other optical components. The curved mirror can also be used to obliquely reflect the incident light vertically incident into the second optical path channel onto the object to be measured 8 and converge at the measured position.

[0028] Furthermore, the device further includes a beam guiding assembly 14, as Figure 1 shown. The beam guiding assembly 14 includes several reflectors arranged at preset positions and preset inclination angles. The second polarized light emitted from the second polarized light source is reflected by the reflectors in different directions in the beam guiding assembly 14 and then incident on the object to be measured along the second optical path channel of the lens assembly 6.

[0029] In some cases, there are two second polarized light sources and two second photoelectric sensors. The two second polarized light sources respectively emit second polarized light, and the two second detection lights are symmetrically incident on the second optical path channel along the axis of the lens assembly. Correspondingly, they can obliquely incident on the measured position from both sides of the measured position of the object to be measured. The two second detection lights reflected by the object to be measured are respectively incident on the corresponding second photoelectric sensors, and two longitudinal magneto-optical Kerr signals can be obtained through analysis, thereby reducing the noise signal and enhancing the detection accuracy of the in-plane direction magnetism.

[0030] As a feasible implementation, Figure 2 is a schematic structural diagram of a magnetic detection device using another optical path design provided by an embodiment of the present invention. As Figure 2 shown, the magnetic detection device provided by the present invention can also have another optical path form. A second light source 9 is provided and the second polarized light emitted by it passes through the second polarizer 10 and is incident into the second optical path channel and obliquely incident on the object to be measured 8. The second polarized light reflected back by the object to be measured 8 is emitted in another second optical path channel and is incident on the second photoelectric sensor 13 through the second analyzer 12. Figure 2 The optical path setting shown in Figure 1 Although the optical path structures of the optical path settings shown are different, the design concepts are the same. Users can flexibly select one of the optical path structures for magnetic detection according to the actual situation.

[0031] In some cases, based on Figure 2 the structural diagram of the magnetic detection device shown, the device can also include a second beam splitter 11, asFigure 3 As shown, the second polarized light emitted from the second polarized light source enters the second optical path channel at least through the second beam splitter 11, and the second polarized light reflected by the object under test 8 irradiates the second photoelectric sensor 13 at least through the second beam splitter 11.

[0032] As a feasible implementation, in the second optical path channel in some cases, there are two beams of second polarized light symmetrically incident on the object under test 8. The second polarized light incident on the object under test 8 in the left second optical path channel will be reflected by the object under test 8 and then exit from the right second optical path channel. At this time, there is also the second polarized light that is being incident in the right second optical path channel, so there will be a problem of shared optical paths. Therefore, a second beam splitter 11 is provided in the path of the second polarized light to separate the two beams of light sharing the optical path.

[0033] Please refer to Figure 1 、 Figure 3 which shows two different forms of optical paths. Among them, Figure 1 in the shown implementation, there is one second beam splitter 11, and both the incident optical path and the reflected optical path of the second polarized light pass through the same second beam splitter 11; Figure 3 in the shown implementation, there are two second beam splitters 11, and the incident optical path and the reflected optical path of the second polarized light pass through different second beam splitters 11.

[0034] As Figure 1 shown, the second incident optical path of the object under test 8 is composed of the second light source 9, the second polarizer 10, the second beam splitter 11, the beam guiding assembly 14 and the lens assembly 6. The second exit optical path of the object under test 8 is composed of the lens assembly 6, the beam guiding assembly 14, the second beam splitter 11, the second analyzer 12 and the second photoelectric sensor 13.

[0035] The beam guiding assembly 14 adjusts the direction of the second polarized light through a plurality of reflectors, so that the second polarized light is aligned with the second optical path channels on both sides of the lens assembly 6, and is focused on the object under test 8 at a preset inclination angle after passing through the second optical path channel. The light reflected from the object under test 8 returns to the beam guiding assembly 14 through the second optical path channel in the lens assembly 6, is guided by the beam guiding assembly 14 and then reaches the second analyzer 12, and finally enters the second photoelectric sensor 13.

[0036] Furthermore, the device further includes: a plurality of excitation devices arranged within a preset distance from the object under test. The excitation device is used to generate a magnetic field acting on the object under test.

[0037] The magnetic detection device provided by the embodiment of the present invention is provided with two sets of optical paths in one set of devices. It can generate polarized light that vertically irradiates the object to be measured through one set of optical paths to detect the polar magneto-optic Kerr effect, and at the same time generate two beams of polarized light that obliquely irradiate the object to be measured through the other set of optical paths to detect the longitudinal magneto-optic Kerr effect. Moreover, the two sets of optical paths can be aligned with the same position of the object to be measured, so as to simultaneously obtain the detection results of the polar magneto-optic Kerr effect and the longitudinal magneto-optic Kerr effect at the same detection position, without adjusting the optical path and without calibrating the position. This not only reduces the optical path cost but also improves the detection accuracy.

[0038] It should also be noted that the term "comprising", "including" or any other variation thereof is intended to cover non-exclusive inclusion, so that a process, method, commodity or device including a series of elements includes not only those elements but also other elements not expressly listed, or also includes elements inherent in such process, method, commodity or device. Without further limitation, an element defined by the statement "including a..." does not exclude the existence of additional identical elements in the process, method, commodity or device including the said element.

[0039] This specification can be described in the general context of computer-executable instructions executed by a computer, such as program modules. Generally, program modules include routines, programs, objects, components, data structures, etc. that perform specific tasks or implement specific abstract data types. This specification can also be practiced in a distributed computing environment where tasks are performed by remote processing devices connected through a communication network. In a distributed computing environment, program modules can be located in local and remote computer storage media including storage devices.

[0040] The various embodiments of the present invention are described in a progressive manner. The same or similar parts between the various embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the embodiments of the device, equipment, and non-volatile computer storage medium, since they are basically similar to the method embodiments, the description is relatively simple, and the relevant parts can refer to the partial description of the method embodiments.

[0041] The above describes specific embodiments of the present invention. Additionally, the processes depicted in the drawings do not necessarily require the specific order or continuous order shown to achieve the desired result. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0042] The above are only embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, various modifications and variations can be made to the embodiments of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the embodiments of the present invention shall be included within the protection scope 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; 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 measured object from the 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 and irradiates the first photoelectric sensor; 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 irradiates the second photoelectric sensor.

2. A magnetic detection device according to claim 1, characterized in that: A reflective element is arranged 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 at 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.

3. A magnetic detection device according to claim 2, characterized in that: The reflective element is a plane mirror or a curved mirror.

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

5. A magnetic detection device according to claim 1, characterized in that: A lens element is arranged in the first optical path channel, 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.

6. A magnetic detection device according to claim 1, characterized in that: The device also 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.

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

8. A magnetic detection device according to claim 1, characterized in that: There are two second polarized light sources, and two second photoelectric sensors. The two second polarized light sources respectively emit second polarized light, and the two beams of the second polarized light are respectively incident on the second optical path channel symmetrically along the axis of the lens assembly; the two beams of the second polarized light reflected by the object to be measured are respectively incident on the corresponding second photoelectric sensors.

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

10. A magnetic detection device according to claim 9, characterized in that: Two second beam splitters are provided, and the two second polarized light beams are configured to enter the object to be measured through at least one of the second beam splitters, and the second polarized light reflected by the object to be measured enters the photoelectric sensor through at least the other of the second beam splitters.

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