Optical path correction method for magnetic domain imaging equipment

Abstract

The present invention discloses an optical path correction method for a magnetic domain imaging device, and belongs to the field of magnetic domain imaging technology. The method comprises: causing detection light emitted by a light source to be incident on a digital micromirror device (DMD); reflecting the detection light toward the position of the object to be measured through a preset reflection area of ​​the digital micromirror device (DMD); when a light spot is formed on the object to be measured, calculating the light intensity of the light spot, and adjusting the preset reflection area of ​​the digital micromirror device (DMD) through the light intensity. The present invention can quickly and easily achieve optical path alignment or optical path adjustment through the above scheme, reducing the difficulty of optical path adjustment.

Description

Technical Field

[0001] The invention relates to the technical field of magnetic domain imaging, and in particular to an optical path correction method for magnetic domain imaging equipment. Background Art

[0002] In current magnetic domain imaging equipment, the incident light path of the object to be measured is composed of a light source, a polarizer, an objective lens, etc., and the reflected light path of the object to be measured is composed of an objective lens, an analyzer, a camera, etc.

[0003] When testing the object to be tested, the test light emitted by the light source is required to reach the object to be tested through the incident light path and form a light spot at the tested position of the object to be tested. Therefore, the light path needs to be adjusted accordingly before starting the test. Since the light spot formed by the test light at the tested position of the object to be tested is usually small, for example, the light spot size in some cases is only a few microns, high precision is required when adjusting the light path, making the light path adjustment process more difficult and inefficient. Summary of the invention

[0004] The present invention provides an optical path correction method for a magnetic domain imaging device, which is used to solve at least one of the above technical problems.

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

[0006] On the one hand, the present invention provides a method for correcting the optical path of a magnetic domain imaging device, the method comprising: making detection light emitted by a light source incident on a digital micromirror device (DMD); reflecting the detection light toward the position of an object to be measured through a preset reflection area of ​​the digital micromirror device (DMD); when a light spot is formed on the object to be measured, calculating the light intensity of the light spot, and adjusting the preset reflection area of ​​the digital micromirror device (DMD) according to the light intensity.

[0007] In a possible implementation of the present invention, before reflecting the detection light toward the position of the object to be measured through the preset reflection area of ​​the digital micromirror device DMD, the method also includes: adjusting each secondary reflection area of ​​the digital micromirror device DMD to reflect the detection light in turn; and determining the preset reflection area based on the secondary reflection area that causes the detection light to form a light spot on the object to be measured.

[0008] In a possible implementation of the present invention, the preset reflection area of ​​the digital micromirror device DMD is adjusted by the light intensity, including: when a secondary reflection area is provided on the digital micromirror device DMD, adjusting the position of the secondary reflection area; comparing the light intensity of the light spot formed on the object under test before and after the adjustment, and adjusting the preset reflection area to include a secondary reflection area corresponding to a stronger light intensity.

[0009] In a possible implementation of the present invention, if the light intensities of the light spots formed on the object to be measured are equal before and after the adjustment, the adjustment of the preset reflection area is terminated.

[0010] In a possible implementation of the present invention, the preset reflection area of ​​the digital micromirror device DMD is adjusted by the light intensity, including: when at least two secondary reflection areas are provided on the digital micromirror device DMD, comparing the light intensities of the detection lights respectively reflected by the secondary reflection areas to form light spots on the object under test; adjusting the digital micromirror device DMD to move the secondary reflection area to the position of the secondary reflection area corresponding to the maximum light intensity in the light intensity; and adjusting the preset reflection area to include the secondary reflection area after the move.

[0011] In a possible implementation of the present invention, if the detection lights respectively reflected by the moved secondary reflection areas form light spots on the object to be measured with equal intensities and / or the intensity difference is within a preset difference range, the adjustment of the preset reflection area is terminated.

[0012] In a possible implementation of the present invention, the preset reflection area of ​​the digital micromirror device DMD is adjusted by the light intensity, including: when at least three secondary reflection areas are provided on the digital micromirror device DMD, the position of the detection light on the digital micromirror device DMD is calculated according to the light intensity of the light spots formed on the object to be measured by the detection light reflected by the secondary reflection areas respectively and the positions of the secondary reflection areas; and the position of the preset reflection area is adjusted according to the position of the detection light on the digital micromirror device DMD.

[0013] In a possible implementation of the present invention, the distance between the center of the secondary reflection area and the center of the detection light spot formed by the detection light on the digital micromirror device DMD is D, and the light intensity of the light spot corresponding to the secondary reflection area is W, and the mapping relationship D between D and W is calibrated as D= f (W); According to the position of the three secondary reflection areas, D = f (W), calculating the position of the detection light on the digital micromirror device DMD by means of triangulation positioning.

[0014] In a possible implementation of the present invention, the coordinates of the center of the light spot on the digital micromirror device DMD are ( x L , y L ); the coordinates of the three secondary reflection areas on the digital micromirror device DMD and the light intensities of the corresponding light spots are: the first secondary reflection area, the coordinates are ( x 1, y 1), the corresponding light intensity is W1; The second secondary reflection area, coordinates are ( x 2, y 2), the corresponding light intensity is W 2; The third secondary reflection area, coordinates are ( x 3, y 3), the corresponding light intensity is W 3;

[0015] By solving the following system of equations ( x L , y L ) to calculate the position of the detection light on the digital micromirror device DMD:

[0016] .

[0017] In a possible implementation of the present invention, the secondary reflection areas are arranged in a regular polygon on the digital micromirror device DMD. If the detection lights reflected by the moved secondary reflection areas respectively form light spots on the object to be measured with equal intensities and / or the intensity difference is within a preset difference range, the center of the preset reflection area is adjusted to the center position of the regular polygon.

[0018] The optical path correction method of a magnetic domain imaging device provided by the present invention has the following beneficial effects:

[0019] The optical path structure of the present invention adopts a digital micromirror device DMD. By reflecting the detection light through different reflection areas or reflection units set on the digital micromirror device DMD, the incident surface or incident direction of the detection light when it enters the object to be measured can be changed. It can not only adapt to the detection requirements of different objects to be measured or different magnetic domains, but also change the incident surface or incident direction by changing the reflection area. The scheme does not need to change the position of the light source, which reduces the installation cost and maintenance cost of the optical path. At the same time, through the digital micromirror device DMD introduced in the optical path structure, the intensity of the light spot formed by the detection light on the object to be measured is adjusted to adjust the preset reflection area on the digital micromirror device DMD. The alignment or correction of the optical path can be achieved by adjusting the digital micromirror device DMD, which reduces the difficulty of adjustment and installation of the optical path. In addition, the digital micromirror device DMD has a fast reaction speed, which can realize the rapid alignment and adjustment of the optical path, and also improve the efficiency of the optical path alignment. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the prior art descriptions. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0021] Figure 1 An optical path structure diagram of a magnetic domain imaging device provided by the present invention;

[0022] Figure 2 A flow chart of an optical path correction method for a magnetic domain imaging device provided by the present invention;

[0023] Figure 3 A schematic diagram of a reflection area before correction provided by the present invention;

[0024] Figure 4 A schematic diagram of a corrected reflection area provided by the present invention.

[0025] Figure 5 Another schematic diagram of a reflection area before correction provided by the present invention.

[0026] Among them, 101, light source; 102, optical fiber; 103, polarizer; 104, prism; 105, digital micromirror device DMD; 106, spectroscope; 107, objective lens; 108, analyzer; 109, camera; 110, light trap assembly; 200, object to be measured; 301, detection light spot; 302, preset reflection area; 303, first secondary reflection area; 304, second secondary reflection area; 305, third secondary reflection area; 306, fourth secondary reflection area; C1, center of the first secondary reflection area; C2, center of the second secondary reflection area; C3, center of the third secondary reflection area; CP, center of the preset reflection area; CL, center of the detection light spot. DETAILED DESCRIPTION

[0027] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the technical solutions in the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the present invention. Obviously, the described embodiments 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 creative work should fall within the scope of protection of the present invention.

[0028] Figure 1 The optical path structure diagram of a magnetic domain imaging device provided by the present invention is Figure 1In the figure, the light source 101, the optical fiber 102, the polarizer 103, the prism 104, the digital micromirror device DMD 105, the beam splitter 106 and the objective lens 107 constitute the incident light path of the object 200 to be measured, and the objective lens 107, the beam splitter 106, the polarizer 108 and the camera 109 constitute the outgoing light path of the object 200 to be measured. The light emitted from the light source 101 is outputted through the optical fiber 102, and then enters the preset reflection area of ​​the digital micromirror device DMD105 after passing through the polarizer 103 and the prism 104. There are a number of micro-reflection units similar to small lenses on the digital micromirror device DMD105, and each secondary reflection area is composed of at least one micro-reflection unit. The light reflected by different secondary reflection areas on the digital micromirror device DMD105 enters different positions of the objective lens 107 after passing through the beam splitter 106, so as to reach the object under test 200 with different incident planes or incident directions. The light reflected by the object under test 200 enters the camera 109 after passing through the objective lens 107, the beam splitter 106 and the analyzer 108, so that the camera 109 obtains the magnetic domain images of the object under test 200 at different incident planes or incident directions.

[0029] That is, when magnetic domain imaging is performed on the object under test 200, a preset reflection area for reflecting the detection light will be predetermined on the digital micromirror device DMD105. However, when setting the optical path, it is usually difficult to determine the position where the detection light is irradiated on the digital micromirror device DMD105, which results in the detection light being unable to be located in the predetermined reflection area. In this way, when the reflection unit in the preset reflection area is controlled to try to reflect the detection light, there may be some reflection units where there is no detection light to reflect, and then an incomplete light spot, a weak light spot intensity, or even no light spot may appear on the object under test. At this time, the optical path needs to be adjusted and corrected so that the detection light is roughly hit at the center of the preset reflection area of ​​the digital micromirror device DMD105, so that the detection light reflected by the reflection unit in the preset reflection area can form a strong and complete light spot on the object under test 200, thereby realizing the detection of the object under test 200.

[0030] The preset reflection area refers to the reflection area selected by the user. When using the magnetic domain imaging device, the specific position and / or range of the preset reflection area is used to control the corresponding reflection unit on the digital micromirror device DMD105 to reflect the detection light toward the object under test 200 or to other directions. The secondary reflection area refers to the area composed of at least part of the reflection units of the digital micromirror device. The reflection states of the reflection units in the same secondary reflection area are the same.

[0031] by Figure 1 Taking the optical path structure shown in as an example, the optical path correction method in the present invention is explained. Figure 2 A flow chart of a method for correcting an optical path of a magnetic domain imaging device provided by the present invention, such as Figure 2As shown, the optical path correction method of the magnetic domain imaging device provided in the present invention at least includes the following execution steps:

[0032] Step 201: Make the detection light emitted by the light source incident on the digital micromirror device (DMD).

[0033] When the optical path needs to be corrected, the light source 101 is started to emit detection light, which is output to the polarizer 103 through the optical fiber 102 and changed into polarized light, and then enters the digital micromirror device DMD105 through the prism 104.

[0034] Step 202: Reflect the detection light toward the location of the object to be detected through the preset reflection area of ​​the digital micromirror device (DMD).

[0035] A preset reflection area for reflecting detection light is pre-set on the digital micromirror device DMD105. The number of reflection units included in the preset reflection area can be one, two, three or even more. The specific number can be adjusted according to the detection requirements of the object under test 200, and the present invention does not limit this.

[0036] After the detection light enters the digital micromirror device DMD105 , it is reflected by the aforementioned preset reflection area, and the detection light is reflected to the location of the object to be detected 200 .

[0037] In one example, the aforementioned preset reflection area is selected and determined in a secondary reflection area on the digital micromirror device DMD105 that enables the detection light to form a light spot on the object under test 200, and the specific determination process is as follows:

[0038] First, the detection light is made incident on the digital micromirror device DMD105;

[0039] Secondly, the digital micromirror device DMD105 is adjusted so that each secondary reflection area on it reflects the detection light in turn, and detects whether a light spot is formed on the object under test 200 during the reflection;

[0040] Finally, the preset reflection area is determined by the secondary reflection area that enables the detection light to form a light spot on the object 200. That is, the position of the preset reflection area is determined according to the position of the secondary reflection area. In some cases, the center of the preset reflection position can be adjusted to coincide with the center of the secondary reflection area; in addition, the digital micromirror device DMD105 may have multiple secondary reflection areas that enable the detection light to form a light spot on the object 200. In this case, the preset reflection area can also include one, two, three or even more of the secondary reflection areas.

[0041] Step 203: When a light spot is formed on the object to be measured, the light intensity of the light spot is calculated, and the preset reflection area of ​​the digital micromirror device DMD is adjusted according to the light intensity.

[0042] According to the above content, when the preset reflection area reflects the detection light, the detection light can form a light spot on the object to be measured 200, and the light intensity of the light spot is one of the criteria for judging the alignment of the optical path and can be used as a reference for adjusting the preset reflection area. The calculation of the light spot intensity here can be achieved through existing technology or algorithms, and the present invention will not be elaborated here.

[0043] In one example, adjusting the preset reflection area of ​​the digital micromirror device DMD105 according to the light intensity of the light spot specifically includes:

[0044] 1) When a secondary reflection area is provided on the digital micromirror device DMD105:

[0045] Adjust or change the position of the preset reflection area. When adjusting the position here, it is adjusted based on the position of the secondary reflection area determined above, which can make the detection light form a light spot on the object under test 200, so as to ensure the adjustment efficiency of the preset reflection area and avoid adjusting to the position of the reflection area that cannot make the detection light form a light spot on the object under test 200.

[0046] Compare the intensities of the light spots formed on the object under test 200 before and after the position adjustment. If the intensity of the light spots formed on the object under test increases after the position adjustment, update the position of the preset reflection area according to the position of the secondary reflection area after the position adjustment. For example, use the secondary reflection area as the preset reflection area, or make the preset reflection area include the corresponding secondary reflection area. If the intensity of the light spots formed on the object under test 200 decreases after the position adjustment, continue to adjust the preset reflection area to other positions, that is, move the preset reflection area to the position of the secondary reflection area where the light spots with larger intensity are formed.

[0047] Further, when the light intensity of the light spot formed on the measured object 200 before and after the position adjustment of the secondary reflection area is equal, the adjustment of the preset reflection area is ended. Alternatively, when the light intensity difference of the light spot formed on the measured object 200 before and after the position adjustment is within the preset difference range, the adjustment of the preset reflection area is ended.

[0048] 2) When two secondary reflection areas are provided on the digital micromirror device DMD105:

[0049] The intensity of the light spots formed by the detection light reflected by the two secondary reflection areas on the object under test 200 is calculated, and the light intensities are compared to move the preset reflection area to the position of the reflection area corresponding to the light spot with larger light intensity. For example, the two secondary reflection areas form two light spots on the object under test 200, one on the left and one on the right, and the light spot on the right has stronger intensity. At this time, the two reflection areas can be moved as a whole (the relative positions of the two remain unchanged) to the position of the reflection area corresponding to the light spot on the right.

[0050] The preset reflection area is updated to include two secondary reflection areas after the moving position. It should be noted that, since the preset reflection area includes two secondary reflection areas, and the moving step size during the movement may be 1, the preset reflection area before and after the movement may include an identical secondary reflection area. For example, the preset reflection area before the movement includes two secondary reflection areas A and B. If the detection light reflected by the secondary reflection area B forms a light spot on the object 200 with a stronger light intensity, when the preset reflection area is moved to the position of B, assuming that the moving step size is 1, the preset reflection area after the movement may include two secondary reflection areas B and C.

[0051] Furthermore, if the light intensities of the light spots formed by the detection lights reflected by the two secondary reflection areas after the position movement on the object to be measured 200 are equal, and / or the light intensity difference is within a preset difference range, the adjustment of the preset reflection area is terminated.

[0052] That is, in this case, the preset reflection area is adjusted by moving the preset reflection area to the position of the secondary reflection area corresponding to the light spot with stronger light intensity, and the adjustment is ended until the light intensities of the detection lights reflected by the two secondary reflection areas contained in the preset reflection area forming light spots on the object to be measured 200 are equal and / or the light intensity difference is within the preset difference range.

[0053] 3) When three secondary reflection areas are provided on the digital micromirror device DMD105:

[0054] The light intensity of the light spot formed by the detection light reflected by the three secondary reflection areas on the object to be measured 200 is calculated, and the position of the detection light on the digital micromirror device DMD105 is calculated according to the light intensity and the position of the corresponding secondary reflection area. Then, according to the position of the detection light on the digital micromirror device DMD105, the position of the preset reflection area is adjusted, for example, so that the center of the preset reflection area is close to or coincides with the center of the detection light on the digital micromirror device DMD105.

[0055] The preset reflection area is moved to the center of the position of the detection light on the digital micromirror device DMD105 and the position of the preset reflection area is updated. It should be noted that the preset reflection area before and after the movement may include one or two identical secondary reflection areas.

[0056] Furthermore, if the light intensities of the light spots formed by the detection lights reflected by the three secondary reflection areas after position movement on the object to be measured 200 are equal, and / or the light intensity difference is within a preset difference range, the adjustment of the preset reflection area is terminated.

[0057] That is, in some cases, the preset reflection area is adjusted by moving the preset reflection area toward the center of the position of the detection light on the digital micromirror device DMD105, and the adjustment is ended until the light intensities of the light spots formed by the detection lights reflected by the three reflection areas included in the preset reflection area on the object to be measured are equal and / or the light intensity difference is within a preset difference range.

[0058] When the number of secondary reflection areas included in the preset reflection area is four or more, the adjustment principle and process are the same or similar to those when it includes two or three secondary reflection areas, and the present invention will not elaborate on them here.

[0059] For example, Figure 3 The preset reflection area 302 includes four secondary reflection areas, namely a first secondary reflection area 303, a second secondary reflection area 304, a third secondary reflection area 305 and a fourth secondary reflection area 306. After the detection light is incident on the digital micromirror device DMD105, a detection light spot 301 is formed on the digital micromirror device DMD105. When these four secondary reflection areas reflect the detection light, three of the secondary reflection areas can form corresponding light spots on the object under test 200 (the reflection area below cannot receive the detection light, that is, it cannot reflect the detection light to form a light spot). Since the position where the detection light hits the digital micromirror device DMD105, that is, the position of the detection light spot 301 and the preset reflection area 302 do not overlap, when different secondary reflection areas reflect the detection light, the light spots formed on the object under test 200 have inconsistent intensities, and the difference between them is large. At this time, according to the above-mentioned adjustment principle or adjustment process, the preset reflection area 302 is moved to the position of the reflection area with stronger light spot intensity (the first secondary reflection area 303 is closer to the center of the detection light, and the corresponding light spot intensity formed is the strongest, so the preset reflection area 302 is moved to the position of the first secondary reflection area 303, that is, moved upward), until the detection light reflected by the preset reflection area 302 forms four light spots on the object under test 200 with consistent intensities and / or the difference satisfies the preset difference range, and the adjustment is ended, and finally adjusted to Figure 4 The position shown, that is, the center position of the preset reflection area 302 coincides with the center position of the detection light spot 301 formed when the detection light hits the digital micromirror device DMD105.

[0060] In one example, the distance between the center of the secondary reflection area and the center of the detection light spot formed by the detection light on the digital micromirror device DMD is D, and the light intensity of the light spot corresponding to the secondary reflection area is W, and the mapping relationship between D and W is calibrated as D= f (W); According to the position of the three secondary reflection areas, D = f (W), the position of the detection light on the digital micromirror device DMD is calculated by triangulation. Mapping relationship D =f (W) is mainly determined by the device, so the mapping relationship D= f (W) is used for adjusting the preset area. Mapping relationship D = f (W) can be analyzed and derived through the device structure, or obtained through multiple experiments. More specifically, the mapping relationship D= can be obtained by determining that the detection light is irradiated at the center of the digital micromirror device DMD105 and reflecting by setting secondary reflection areas at different distances. f (W).

[0061] Specifically, Figure 5 In the illustrated case, three secondary reflection areas are selected to calculate the position of the detection light on the digital micromirror device DMD105, so as to adjust the position of the preset area. Specifically, the coordinates of the center C1 of the first secondary reflection area are ( x 1, y 1), the light intensity of the light spot formed by the detection light reflected by the first secondary reflection area 303 is W 1; The coordinates of the center C2 of the second secondary reflection area are ( x 2, y 2), the light intensity of the light spot formed by the detection light reflected by the second secondary reflection area 304 is W 2; The coordinates of the center of the third secondary reflection area C3 are ( x 3, y 3), the light intensity of the light spot formed by the detection light reflected by the third secondary reflection area 305 is W 3. The coordinates of the detection light spot center CL on the digital micromirror device DMD are ( x L , y L ).

[0062] When the three secondary reflection areas are capable of reflecting at least part of the detection light to form a light spot on the object 200, the position of the detection light spot center CL on the digital micromirror device DMD105 can be calculated based on the positions of the three secondary reflection areas and the light intensity of the light spot. Specifically, it can be calculated by solving the following equation group: x L , y L ) to calculate the position of the detection light on the digital micromirror device DMD:

[0063] .

[0064] in, , , According to the mapping relationship D= f(W), combined with the corresponding light intensity W 1. W 2. W 3 is calculated. Therefore, the above equations can be transformed into:

[0065] .

[0066] In this system of equations, only x L , y L Unknown, can be solved by solving the equations to obtain x L , y L .

[0067] After obtaining the coordinates of the center CL of the detection light spot on the digital micromirror device DMD105 ( x L , y L ), the position of the preset reflection area 302 can be moved, for example, the center CP of the preset reflection area and the center CL of the detection light spot can be made close to or even overlap each other, so as to further determine the corresponding secondary reflection area for detection.

[0068] In one example, the preset reflection area 302 includes three or more secondary reflection areas (for example, including Figure 3-4 When the adjustment of the preset reflection area 302 is completed, that is, when the detection light reflected by the at least three secondary reflection areas forms a light spot on the object to be measured 200 with equal intensity and / or the light intensity difference is within the preset difference range, not only the at least three secondary reflection areas after adjustment can be used as the preset reflection area 302, but also the center position of the regular polygon can be used as the center position of the preset reflection area 302. This is because, after the adjustment is completed, the center position of the detection light spot 301 formed by the detection light hitting the digital micromirror device DMD105 and the center position of the regular polygon roughly coincide with each other. Due to the geometric characteristics of the regular polygon, when the optical axis is at the center position of the regular polygon, it can be ensured that the detection light reflected by the secondary reflection areas arranged in a regular polygon forms a light spot with equal intensity on the object to be measured 200.

[0069] After the preset reflection area 302 is adjusted, it can be ensured that the detection light reflected by the preset reflection area 302 forms a light spot with the strongest intensity on the object under test 200, and the light intensity of the light spot reflected by the secondary reflection area included in the preset reflection area 302 is equal and / or the intensity difference is within the preset difference range, that is, the alignment of the optical path is achieved.

[0070] The aforementioned preset difference range can be set according to actual needs. For example, the difference can be set to be no greater than 5% of the light intensity before adjustment.

[0071] The present invention achieves adjustment or alignment of the optical path by introducing a digital micromirror device DMD105 into the optical path structure and adjusting a preset reflection area on the digital micromirror device DMD105 by detecting the position of light hitting the digital micromirror device DMD105, thereby reducing the difficulty of adjusting or aligning the optical path, shortening the adjustment time, and improving the use efficiency of the magnetic domain imaging device.

[0072] The various embodiments of the present invention are described in a progressive manner, and 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.

[0073] It will be appreciated by those skilled in the art that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0074] It should also be noted that the terms "include", "comprises" or any other variations thereof are 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 explicitly listed, or also includes elements inherent to such process, method, commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the process, method, commodity or device including the elements.

[0075] The above are only embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for correcting the optical path of a magnetic domain imaging device, characterized in that: The method comprises: The detection light emitted by the light source is made incident on a digital micromirror device (DMD); The detection light is reflected toward the position of the object to be measured through the preset reflection area of ​​the digital micromirror device DMD, so that the camera obtains the magnetic domain image of the object to be measured at different incident planes or incident directions; When a light spot is formed on the object to be measured, the light intensity of the light spot is calculated, and a preset reflection area of ​​the digital micromirror device DMD is adjusted according to the light intensity, including: When at least three secondary reflection areas are provided on the digital micromirror device DMD, the position of the detection light on the digital micromirror device DMD is calculated according to the light intensity of the light spots formed on the object to be measured by the detection light reflected by the secondary reflection areas respectively and the positions of the secondary reflection areas; and the position of the preset reflection area is adjusted according to the position of the detection light on the digital micromirror device DMD; The distance between the center of the secondary reflection area and the center of the detection light spot formed by the detection light on the digital micromirror device DMD is D, and the light intensity of the light spot corresponding to the secondary reflection area is W. The mapping relationship between D and W is calibrated as D= f (W); According to the position of the three secondary reflection areas, D = f (W), calculating the position of the detection light on the digital micromirror device DMD by means of triangulation; The coordinates of the center of the light spot on the digital micromirror device DMD are ( x L , y L ); the coordinates of the three secondary reflection areas on the digital micromirror device DMD and the light intensities of the corresponding light spots are: the first secondary reflection area, the coordinates are ( x 1, y 1), the corresponding light intensity is W 1; The second secondary reflection area, coordinates are ( x 2, y 2), the corresponding light intensity is W 2; The third secondary reflection area, coordinates are ( x 3, y 3), the corresponding light intensity is W 3; By solving the following system of equations ( x L , y L ) to calculate the position of the detection light on the digital micromirror device DMD: The secondary reflection areas are arranged in a regular polygon on the digital micromirror device DMD. If the detection lights reflected by the moved secondary reflection areas respectively form light spots on the object to be measured with equal intensities and / or the intensity difference is within a preset difference range, the center of the preset reflection area is adjusted to the center position of the regular polygon.

2. The optical path correction method of a magnetic domain imaging device according to claim 1, characterized in that: Before reflecting the detection light toward the position of the object to be detected through the preset reflection area of ​​the digital micromirror device DMD, the method further includes: Adjusting each secondary reflection area of ​​the digital micromirror device DMD to reflect the detection light in sequence; The preset reflection area is determined according to a secondary reflection area that causes the detection light to form a light spot on the object to be detected.

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