Laser collimation adjustment and included angle and distance measurement method, system, equipment and medium

Abstract

The invention provides a laser collimation adjustment and included angle and distance measurement method, system and device and a medium. The optical equipment comprises a light path adjusting device and an objective lens, and laser passes through the objective lens after passing through the light path adjusting device; the method comprises the following steps: P1, controlling the light path adjusting device to change the inclination angle of the laser, so that the laser is parallel to the optical axis of the objective lens; and P2, controlling the light path adjusting device to translate the laser, so that the light beam center of the laser coincides with the optical axis of the objective lens. The method can quickly and accurately realize laser collimation adjustment and measure the included angle and the distance between the laser and the optical axis of the objective lens.

Description

Technical Field

[0001] The present invention relates to the technical field of laser alignment of optical equipment, and in particular to a laser alignment adjustment method and a laser alignment adjustment system for optical equipment, a computer-readable storage medium, and an optical equipment for executing the laser alignment adjustment method and an optical equipment including the laser alignment adjustment system. Background Art

[0002] With the development of scientific research and the upgrading of the photonics industry, the strong demand for the ability to finely characterize the optical properties of materials at the mesoscopic scale and to quickly obtain sample information in real time will promote the advancement of related detection technologies. Optical equipment commonly used for optical measurement uses laser as the excitation light source, which enters the microscope module after passing through the excitation light path, and then irradiates the sample surface. The signal light generated by the sample passes through the microscope module and is collected and processed by the collection light path. In optical equipment, the center of the laser beam often deviates from the optical axis of the objective lens, so that the center of the light spot formed by the laser irradiating the sample surface deviates from the center of the field of view. How to quickly and accurately adjust the laser alignment is an important topic in the research and development of optical equipment. Summary of the invention

[0003] The present invention provides a laser alignment adjustment method for an optical device, wherein the optical device comprises an optical path adjustment device, an imaging device, an objective lens, and a lifting sample stage; a laser is irradiated onto a sample on the lifting sample stage after passing through the optical path adjustment device and the objective lens, and the imaging device can image the sample; the method comprises the following steps:

[0004] Step P11: controlling the lifting and lowering of the lifting sample stage and acquiring a first image having a focused light spot from the imaging device, wherein the focused light spot is a light spot when the laser is in a focused state;

[0005] Step P12: Identify a first coordinate of the center of the focused light spot, and determine whether the absolute value of a first difference between the first coordinate and a reference coordinate of the optical axis of the objective lens is less than a first threshold; the first coordinate is the coordinate of the projection of the center of the focused light spot on a coordinate plane, the reference coordinate is the coordinate of the projection of the optical axis of the objective lens on the coordinate plane, and the coordinate plane is perpendicular to the lifting direction of the lifting sample stage;

[0006] Step P13: when the absolute value of the first difference is greater than or equal to the first threshold, controlling the optical path adjustment device according to the first difference so that the absolute value of the first difference is less than the first threshold; when the absolute value of the first difference is less than the first threshold, not executing step P13;

[0007] Step P21: controlling the lifting sample stage to move up and down and acquiring a second image having a defocused light spot from the imaging device, wherein the defocused light spot is a light spot when the laser is in a defocused state;

[0008] Step P22: Identify a second coordinate of the center of the defocused light spot, and determine whether an absolute value of a second difference between the second coordinate and the reference coordinate of the optical axis of the objective lens is less than a second threshold; the second coordinate is the coordinate of the projection of the center of the defocused light spot on the coordinate plane;

[0009] Step P23: When the absolute value of the second difference is greater than or equal to the second threshold, the optical path adjustment device is controlled according to the second difference so that the absolute value of the second difference is less than the second threshold; when the absolute value of the second difference is less than the second threshold, step P23 is not executed.

[0010] The present invention also provides a laser alignment adjustment method for an optical device, wherein the optical device comprises an optical path adjustment device and an objective lens, and a laser passes through the objective lens after passing through the optical path adjustment device; the method comprises the following steps:

[0011] Step P1: controlling the optical path adjustment device to change the inclination angle of the laser so that the laser is parallel to the optical axis of the objective lens; and

[0012] Step P2: Control the optical path adjustment device to translate the laser so that the center of the laser beam coincides with the optical axis of the objective lens.

[0013] The present invention also provides a laser alignment adjustment system for an optical device, wherein the optical device comprises an optical path adjustment device and an objective lens, and a laser passes through the objective lens after passing through the optical path adjustment device; the laser alignment adjustment system comprises:

[0014] a first control module, used for controlling the optical path adjustment device to change the inclination angle of the laser so that the laser is parallel to the optical axis of the objective lens; and

[0015] A second control module is used to control the optical path adjustment device to translate the laser so that the center of the laser beam coincides with the optical axis of the objective lens.

[0016] The present invention also provides a laser alignment adjustment system for an optical device, the optical device comprising an optical path adjustment device, an imaging device, an objective lens, and a lifting sample stage; a laser is irradiated onto a sample on the lifting sample stage after passing through the optical path adjustment device and the objective lens, and the imaging device can image the sample; the laser alignment adjustment system comprises:

[0017] a first image acquisition module, used to control the lifting and lowering of the lifting sample stage and to acquire a first image with a focused light spot from the imaging device, wherein the focused light spot is a light spot when the laser is in a focused state;

[0018] a first identification and judgment module, used to identify a first coordinate of the center of the focused light spot, and to judge whether the absolute value of a first difference between the first coordinate and a reference coordinate of the optical axis of the objective lens is less than a first threshold; the first coordinate is the coordinate of the projection of the center of the focused light spot on a coordinate plane, the reference coordinate is the coordinate of the projection of the optical axis of the objective lens on the coordinate plane, and the coordinate plane is perpendicular to the lifting direction of the lifting sample stage;

[0019] a first control execution module, configured to control the optical path adjustment device according to the first difference so that the absolute value of the first difference is less than the first threshold value when the absolute value of the first difference is greater than or equal to the first threshold value; and not perform an operation when the absolute value of the first difference is less than the first threshold value;

[0020] a second image acquisition module, used for controlling the lifting and lowering of the lifting sample stage and acquiring a second image with a defocused light spot from the imaging device, wherein the defocused light spot is a light spot when the laser is in a defocused state;

[0021] a second identification and judgment module, used for identifying a second coordinate of the center of the defocused light spot, and judging whether an absolute value of a second difference between the second coordinate and the reference coordinate of the optical axis of the objective lens is less than a second threshold; the second coordinate is the coordinate of the projection of the center of the defocused light spot on the coordinate plane;

[0022] A second control execution module is used to control the optical path adjustment device according to the second difference so that the absolute value of the second difference is less than the second threshold when the absolute value of the second difference is greater than or equal to the second threshold; when the absolute value of the second difference is less than the second threshold, no operation is performed.

[0023] The present invention also provides an optical device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the above-mentioned laser alignment adjustment method when executing the computer program.

[0024] The present invention also provides an optical device, comprising: an optical path adjustment device, an imaging device, an objective lens, a lifting sample stage and a laser alignment adjustment system; a laser is irradiated onto a sample on the lifting sample stage after passing through the optical path adjustment device and the objective lens, and the imaging device can image the sample; the laser alignment adjustment system is the above-mentioned laser alignment adjustment system.

[0025] The present invention also provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, including steps for implementing the above-mentioned laser alignment adjustment method when the computer program is executed by a processor.

[0026] The present invention provides a laser alignment adjustment method and system, optical equipment and medium. In the laser alignment adjustment method, by obtaining a focused light spot, adjusting an optical path adjustment device so that the deviation between the focused light spot and the optical axis of the objective lens is less than a first threshold value, so that the laser can be parallel to the optical axis of the objective lens; then, by obtaining a defocused light spot, adjusting the optical path adjustment device so that the deviation between the defocused light spot and the optical axis of the objective lens is less than a second threshold value, so that the center of the laser beam can coincide with the optical axis of the objective lens. The method can quickly and accurately achieve laser alignment adjustment. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 A schematic structural diagram of an optical device provided by the present invention;

[0028] Figure 2 A schematic structural diagram of another optical device provided by the present invention;

[0029] Figure 3 A schematic diagram of the structure of an optical path adjustment device provided by the present invention;

[0030] Figure 4 for Figure 2 A schematic diagram of the three-dimensional structure of the second adjustment mechanism;

[0031] Figure 5 A flow chart of the laser alignment adjustment method provided by the present invention;

[0032] Figure 6 A schematic diagram of the optical path of the laser beam provided by the present invention, in which the center of the laser beam deviates from the optical axis of the objective lens;

[0033] Figure 7 A position relationship diagram of the focused light spot provided by the present invention in a coordinate plane;

[0034] Figure 8 A schematic diagram of the optical path of the laser provided by the present invention being parallel to the optical axis of the objective lens;

[0035] Fig. 9 A position relationship diagram of the focused light spot and the defocused light spot in the coordinate plane when the laser provided by the present invention is parallel to the optical axis of the objective lens;

[0036] Fig.10 A schematic diagram of a process of deflecting a laser in a first direction provided by the present invention;

[0037] Fig.11A schematic diagram of the optical path in which the laser center provided by the present invention coincides with the optical axis of the objective lens;

[0038] Fig.12 A position relationship diagram of the focused light spot and the defocused light spot in the coordinate plane when the laser center provided by the present invention coincides with the optical axis of the objective lens;

[0039] Fig.13 A schematic structural diagram of a laser alignment adjustment system provided by the present invention.

[0040] Explanation of reference numerals: 10 lifting sample stage, 20 optical path adjustment device, 22 optical adjustment frame, 23 cage right-angle adjustment frame, 30 microscope module, 40 imaging device, 50 laser alignment adjustment system, 51 first control module, 52 second control module, 100 sample, 201 first reflecting element, 202 second reflecting element, 211 first translation mechanism, 212 second translation mechanism, 220 mounting frame, 221 first angle adjustment mechanism, 222 second angle adjustment mechanism, 223 mirror frame, 224 tension spring, 225 top screw, 241 first mounting seat, 242 second mounting seat, 251 first table, 252 second table, 300 objective lens, 301 first Optical element, 302 second optical element, 303 light entrance hole, 511 first image acquisition module, 512 first recognition and judgment module, 513 first control execution module, 521 second image acquisition module, 522 second recognition and judgment module, 523 second control execution module, Re laser, Rf reflected light, S0 coordinate plane, R1 incident laser, R2 first exit laser, R3 second exit laser, B1 focused spot, B2 defocused spot, T center, C optical axis, X first direction, Y second direction, Z third direction, Rx fourth direction, Ry fifth direction, Rz sixth direction, S1 first plane, S2 second plane, H1 first height, H2 second height. DETAILED DESCRIPTION

[0041] Figure 1 A schematic structural diagram of an optical device provided by the present invention; Figure 2 A schematic structural diagram of another optical device provided by the present invention; Figure 3 A schematic diagram of the structure of an optical path adjustment device provided by the present invention; Figure 4 for Figure 2 Schematic diagram of the three-dimensional structure of the second adjustment mechanism. Figure 1-4 It can be seen that the optical device includes: an optical path adjustment device 20, an imaging device 40, an objective lens 300, a lifting sample stage 10 and a laser alignment adjustment system 50; a laser Re is irradiated onto a sample 100 on the lifting sample stage 10 after passing through the optical path adjustment device 20 and the objective lens 300, and the imaging device 40 can image the sample 100.

[0042] In an illustrative embodiment, the optical device includes an excitation optical path module (not shown in the figure), a microscope module 30, a signal collection optical path module (not shown in the figure), and an imaging optical path module (not shown in the figure). The excitation optical path module can generate laser Re that meets user needs. The excitation optical path module includes an optical path adjustment device 20 for adjusting the spatial position and direction of the laser Re transmission. Optionally, the excitation optical path module also includes one or more of the following modules: a polarization state adjustment module for adjusting the polarization state of the laser Re, such as polarization direction, polarization type, etc.; a galvanometer module for changing the transmission direction of the laser Re to achieve laser scanning; a power adjustment module for adjusting the power of the laser Re. The excitation optical path module may also include other optical paths or modules for adjusting the performance of the laser Re. The relevant technical solutions of the excitation optical path module can refer to the Chinese utility model patent application documents with patent application numbers CN202320967287X and CN2023209672846. Optionally, the above modules are arranged between the optical path adjustment device 20 and the microscope module 30. Optionally, the excitation optical path module also includes a laser that generates laser Re (not shown in the figure). The microscope module 30 includes an objective lens 300. The laser Re generated by the excitation optical path module enters the microscope module 30, passes through the objective lens 300, and then irradiates the sample 100 on the lifting sample stage 10. After the sample 100 is irradiated with the laser Re, a reflected light Rf is generated. The reflected light Rf passes through the objective lens 300 in the reverse direction and enters the microscope module 30, and is then received and imaged by the imaging device 40 in the imaging optical path module. In this way, the imaging device 40 can see the light spot irradiated by the laser Re on the sample 100 through the objective lens 300. Of course, if the sample 100 can be excited to generate signal light (not shown in the figure) after being irradiated with the laser Re. Then the signal light can pass through the objective lens 300 in the reverse direction and enter the microscope module 30, and then be collected and processed by the collection optical path module, such as real space imaging or momentum space imaging, and analyzed by a spectrometer to generate spectral data. For the relevant technical solutions of the collection optical path module, please refer to the Chinese utility model patent application documents with application numbers 202222685016.3, 202223066457.1, 202223068712.6 and 202223068881.X. Figure 1 and Figure 2In the illustrated embodiment, the microscope module 30 further includes a first optical element 301 and a second optical element 302. The first optical element 301 reflects the laser Re from the optical path adjustment device 20 to the objective lens 300, and the second optical element 302 transmits the laser Re and reflects the reflected light Rf to the imaging device 40. Optionally, the types of the first optical element 301 and the second optical element 302, the positional relationship between the two, and the orientation of each reflection surface can be adjusted according to the actual application scenario, and the relevant technical solutions can refer to the Chinese utility model patent application document with patent application number CN202321505385.8. The imaging optical path module includes an imaging device 40, which images the light spot formed by the laser Re irradiating the sample 100 after receiving the reflected light Rf. Optionally, the imaging optical path module includes an illumination light source and an illumination transmission optical path (not shown in the figure) for generating illumination light for irradiating the sample 100. The relevant technical solutions of the imaging optical path module can refer to the Chinese utility model patent application document with patent application number CN202321505385.8. Optionally, the imaging device 40 is an industrial camera. When performing laser alignment adjustment, the sample 100 can use a sheet material with a flat surface such as a silicon wafer to form a laser spot of good quality. The lifting sample stage 10 can move along the third direction Z so that the sample 100 is close to or away from the objective lens 300. Usually the third direction Z is a vertical direction, which is perpendicular to the end face of the lifting sample stage 10 on which the sample 100 is placed. The laser alignment adjustment system 50 is respectively connected to the optical path adjustment device 20, the imaging device 40 and the lifting sample stage 10. The laser alignment adjustment system 50 can control the lifting and lowering movement of the lifting sample stage 10 along the third direction Z, and can also receive an image signal from the imaging device 40, and control the optical path adjustment device 20 after analyzing and processing the image signal to realize laser alignment adjustment until the center of the laser Re coincides with the optical axis of the objective lens 300. For ease of description, a coordinate plane S0 is established, which is parallel to the sample 100 and perpendicular to the third direction Z. Optionally, the lifting sample stage 10 can also move in a plane perpendicular to the third direction Z.

[0043] In an illustrative embodiment, the optical path adjustment device 20 includes:

[0044] A first translation mechanism 211, capable of controlling the laser Re to translate along a first direction X;

[0045] A second translation mechanism 212, capable of controlling the laser Re to translate along a second direction Y, the second direction Y intersecting the first direction X and both being parallel to the coordinate plane S0;

[0046] A first angle adjustment mechanism 221, capable of controlling the laser Re to deflect in a first direction X;

[0047] A second angle adjustment mechanism 222 can control the laser Re to deflect in the second direction Y; the lifting direction of the lifting sample stage 10 is a third direction Z movement, and the third direction Z is perpendicular to the first direction X and the second direction Y.

[0048] In this way, the translation and deflection of the laser Re in the first direction X and the second direction Y are controlled by a separate mechanism and are relatively independent of each other; that is, the first translation mechanism 211 independently controls the translation of the laser Re along the first direction X, the second translation mechanism 212 independently controls the translation of the laser Re along the second direction Y, the first angle adjustment mechanism 221 independently controls the deflection of the laser Re in the first direction X, and the second angle adjustment mechanism 222 independently controls the deflection of the laser Re in the second direction Y. The first translation mechanism 211, the second translation mechanism 212, the first angle adjustment mechanism 221 and the second angle adjustment mechanism 222 in the optical path adjustment device 20 can control a plurality of optical elements to achieve the translation and deflection of the laser Re. The type and number of optical elements can be adapted and set according to the actual application scenario. Figure 1-4 In the description, the optical path adjustment device 20 having two reflective elements is used as an example. For other embodiments of the optical path adjustment device 20, reference may be made to the Chinese utility model patent application documents with patent application numbers CN2023219618138 and CN2023220414292, all of which and their descriptions may be introduced into the present invention as embodiments of the optical path adjustment device. Usually, the first direction X is perpendicular to the second direction Y.

[0049] Optionally, the optical path adjustment device 20 further includes a first reflective element 201, which can reflect an incident laser R1 to form a first outgoing laser R2. The first plane S1 is perpendicular to the reflection surface of the first reflective element 201, and usually the incident laser R1 and the first outgoing laser R2 are located in the first plane S1. The first translation mechanism 211 can drive the first reflective element 201 to move in a fourth direction Rx, but the movement direction is not parallel to the reflection surface of the first reflective element 201. For example, the fourth direction Rx is parallel to the first plane S1.

[0050] The optical path adjustment device 20 further includes a second reflective element 202, which can reflect the first emitted laser R2 to form a second emitted laser R3. The reflective surface of the second reflective element 202 is arranged to be inclined to the first plane S1, the first plane S1 and the second plane S2 intersect perpendicularly, and the second translation mechanism 212 can drive the second reflective element 202 to move in a fifth direction Ry, and the fifth direction Ry is perpendicular to the first plane S1 and parallel to the second plane S2;

[0051] Among them, the first angle adjustment mechanism 221 can adjust a first inclination angle (not marked in the figure) of the reflecting surface of the second reflecting element 202 relative to the first plane S1; the second angle adjustment mechanism 222 can adjust a second inclination angle (not marked in the figure) of the reflecting surface of the second reflecting element 202 relative to the first plane S1.

[0052] Specifically, the first translation mechanism and the second translation mechanism are both translation stages. When the incident laser R1 is set to be transmitted along the fourth direction Rx, it reaches the reflection surface of the first reflection element 201 and is reflected to form the first outgoing laser R2. The first outgoing laser R2 is transmitted along the sixth direction Rz. The incident laser R1 and the first outgoing laser R2 are located in the first plane S1, that is, the plane formed by the fourth direction Rx and the sixth direction Rz is parallel to the first plane S1. Optionally, the fourth direction Rx is perpendicular to the sixth direction Rz. Figure 1-4 In the illustrated embodiment, the fourth direction Rx is located in the horizontal direction and is parallel to the first direction X, and the sixth direction Rz is parallel to the third direction Z, that is, the vertical direction. This is determined by the optical path setting between the incident laser R1 and the objective lens 300. Optionally, when the optical path setting between the incident laser R1 and the objective lens 300 is changed, the fourth direction Rx is not parallel to the first direction X (for example, intersecting); and / or the sixth direction Rz is not parallel to the third direction Z (for example, intersecting). The reflecting surface of the first reflecting element 201 is adjusted so that it is perpendicular to the first plane S1 and the angle with the incident laser R1 is 45 degrees. In the present disclosure, the reflecting surface refers to the surface of the reflecting element that plays a reflecting role, and the incident light is reflected as reflected light after reaching the reflecting surface. In this way, the angle between the first outgoing laser R2 and the reflecting surface of the first reflecting element 201 is also 45 degrees, and the incident laser R1 is perpendicular to the first outgoing laser R2. The first outgoing laser R2 is incident on the reflecting surface of the second reflecting element 202 and is reflected as the second outgoing laser R3. The first emitted laser R2 and the second emitted laser R3 are located in the second plane S2. The first plane S1 intersects the second plane S2 perpendicularly.

[0053] Optionally, the first angle adjustment mechanism 221 and the second angle adjustment mechanism 222 can be adjusted so that the reflection surface of the second reflection element 202 is parallel to the fourth direction Rx, and the angle between the second reflection element 202 and the first plane S1 is 45 degrees, so that the angle between the second reflection element 202 and the first emitted laser R2 is 45 degrees, and the second emitted laser R3 is emitted along the fifth direction Ry. The fifth direction Ry is perpendicular to the first plane S1, and the fifth direction Ry is perpendicular to the fourth direction Rx and the sixth direction Rz. Figure 1-4 In the illustrated embodiment, the fifth direction Ry is located in the horizontal direction and is parallel to the second direction Y. This is determined by the optical path setting between the incident laser R1 and the objective lens 300. Optionally, when the optical path setting between the incident laser R1 and the objective lens 300 is changed, the fifth direction Ry is not parallel to the second direction Y (for example, crosses).

[0054] When the laser alignment adjustment system 50 transmits a control instruction to the first translation mechanism 211 so that the first reflective element 201 moves in the fourth direction Rx, the second emitted laser R3 also translates in the fourth direction Rx, thereby causing the laser Re transmitted to the objective lens 300 to translate in the first direction X. When the laser alignment adjustment system 50 transmits a control instruction to the second translation mechanism 212 so that the second reflective element 202 moves in the fifth direction Ry, the second emitted laser R3 also translates in the sixth direction Rz, thereby causing the laser Re transmitted to the objective lens 300 to translate in the second direction Y. In this way, the spatial position of the laser Re can be adjusted by controlling the first translation mechanism 211 and the second translation mechanism 212 to translate, that is, to achieve translation.

[0055] The laser alignment adjustment system 50 transmits control instructions to the first angle adjustment mechanism 221 and the second angle adjustment mechanism 222 respectively to adjust the transmission angle of the second emitted laser R3, thereby controlling the inclination angle of the laser Re relative to the coordinate plane S0 before entering the objective lens 300. The first angle adjustment mechanism 221 can control the laser Re to deflect in the first direction X, that is, the first angle adjustment mechanism 221 can control the spot of the laser Re on the coordinate plane S0 to move along the first direction X. The second angle adjustment mechanism 222 can control the laser Re to deflect in the second direction Y, that is, the second angle adjustment mechanism 222 can control the spot of the laser Re on the coordinate plane S0 to move along the second direction Y.

[0056] In summary, the first translation mechanism 211 can translate the first reflective element 201 in the fourth direction Rx to achieve the translation of the laser Re in the first direction X; the second translation mechanism 212 can translate the second reflective element 202 in the fifth direction Ry to achieve the translation of the laser Re in the second direction Y; the fourth direction Rx is perpendicular to the fifth direction Ry, so that the translation of the laser Re in the first direction X and the second direction Y are relatively independent of each other, and the movement of the laser spot in the first direction X and the second direction Y can be independently adjusted. The first angle adjustment mechanism 221 can control the second reflective element 202 to rotate around a first axis so that the laser Re is deflected in the first direction X; the second angle adjustment mechanism 222 can control the second reflective element 202 to rotate around a second axis so that the laser Re is deflected in the second direction Y. The first axis is perpendicular to the second axis so that the laser Re is also relatively independent of each other in the two deflection directions, and the movement of the laser spot in the first direction X and the second direction Y can be independently adjusted. This adjustment is simple and convenient, and the efficiency is high.

[0057] Figure 3 In the embodiment shown, the incident light first passes through the first reflecting element 201 and then passes through the second reflecting element 202 before being output. Since the transmission path of light is reversible, in another exemplary embodiment, Figure 3 The optical device and the optical path adjustment device therein remain unchanged, and only the incident light and the outgoing light are interchanged (i.e., the transmission direction of the light is reversed), that is, the incident light first passes through the second reflecting element 202, and then passes through the first reflecting element 201. Optionally, there may be other optical path systems between the first reflecting element 201 and the second reflecting element 202, such as one or more reflectors to change the propagation path of the light.

[0058] In an illustrative embodiment, the optical path adjustment device 20 further includes a cage-type right-angle adjustment frame 23 and a first mounting seat 241, the first translation mechanism 211 includes a first table 251, the first reflective element 201 is mounted in the cage-type right-angle adjustment frame 23, the cage-type right-angle adjustment frame 23 is mounted on the first mounting seat 241, and the first mounting seat 241 is mounted on the first table 251. Optionally, the first mounting seat 241 and the first table 251 are an integrated structure.

[0059] In an illustrative embodiment, the optical path adjustment device 20 further includes a second mounting seat 242, and the second translation mechanism 212 includes a second table 252. The optical path adjustment device 20 further includes an optical adjustment frame 22, and the optical adjustment frame 22 includes a first angle adjustment mechanism 221 and a second angle adjustment mechanism 222. The optical adjustment frame 22 is mounted on the second mounting seat 242, and the second mounting seat 242 is mounted on the second table 252. Optionally, the second mounting seat 242 and the second table 252 are an integral structure.

[0060] In an exemplary embodiment, the optical adjustment frame 22 is a two-dimensional pitch adjustment frame, including a mounting frame 220 fixed on a second mounting seat 242 . Figure 4 In the optical adjustment frame 22, a mirror frame 223 is arranged opposite to the mounting frame 220; the second reflective element 202 is fixedly mounted on the mirror frame 223, and the mirror frame 223 and the mounting frame 220 are arranged opposite to each other through a tension spring 224; the first angle adjustment mechanism 221 and the second angle adjustment mechanism 222 respectively adjust the distance between the mounting frame 220 and the mirror frame 223 through a top screw 225; the first angle adjustment mechanism 221 can make the second reflective element 202 rotate around a first axis (not shown in the figure), and the first axis is perpendicular to the fourth direction Rx; the second angle adjustment mechanism 222 can make the second reflective element 202 rotate around a second axis (not shown in the figure), and the second axis is perpendicular to the fifth direction Ry. When balanced, the restoring force generated by the tension spring and the supporting force generated by the top screw balance each other.

[0061] In an exemplary embodiment, one or more of the first translation mechanism 211, the second translation mechanism 212, the first angle adjustment mechanism 221, and the second angle adjustment mechanism 222 are electrically driven. Optionally, all four are electrically driven, so that the optical path can be quickly and accurately adjusted through the control device.

[0062] In an exemplary embodiment, the first reflective element 201 and the second reflective element 202 are both plane reflectors. In the present disclosure, a reflective element refers to an optical element having a reflective function, and may also have other functions. For example, a reflective element may also be a beam splitter or a dichroic mirror.

[0063] During the installation and use of the above optical equipment, it is necessary to ensure that the beam center of the laser Re coincides with the optical axis of the objective lens 300 (including basic coincidence within the error range) to achieve laser collimation and irradiation to the sample 100; that is, the spot center of the laser Re on the surface of the sample 100 is located at the center of the field of view of the sample image obtained by the imaging device 40. However, in fact, the incident laser R1 may deviate from the fourth direction Rx, the second emitted laser R3 may deviate from the fifth direction Ry, and the optical path setting and installation between the incident laser R1 and the objective lens 300 may also produce deviations, so that the final beam center of the laser Re does not coincide with the optical axis of the objective lens 300, and laser collimation adjustment is required. The optical axis of the objective lens is parallel to the third direction Z and perpendicular to the coordinate plane S0. Generally, laser collimation adjustment includes coarse adjustment and fine adjustment. The equipment debugging personnel first need to make a coarse adjustment so that the beam center of the laser Re coincides with the optical axis of the objective lens 300 as close as possible; the coarse adjustment is generally done manually. After the coarse adjustment is completed, fine adjustment is required to accurately achieve the coincidence of the beam center of the laser Re with the optical axis of the objective lens 300.

[0064] Figure 5 The flowchart of the laser alignment adjustment method provided by the present invention. Figure 1-5 It can be seen that the optical device includes: an optical path adjustment device 20, an imaging device 40, an objective lens 300, and a lifting sample stage 10; a laser Re is irradiated on a sample 100 on the lifting sample stage 10 after passing through the optical path adjustment device 20 and the objective lens 300, and the imaging device 40 can image the sample 100. The laser alignment adjustment method is performed by the laser alignment adjustment system 50, including steps P1 and P2. Step P1 includes steps P11, P12, and P13; step P2 includes steps P21, P22, and P23.

[0065] Step P1: Control the optical path adjustment device 20 to change the inclination angle of the laser Re so that the laser Re is parallel to the optical axis of the objective lens 300. Specifically, the optical path adjustment device 20 can change the inclination angle (i.e., the angle) of the laser Re relative to the optical axis of the objective lens 300. The first angle adjustment mechanism 221 can change the component of the inclination angle in the first direction X, and the second angle adjustment mechanism 222 can change the component of the inclination angle in the second direction Y.

[0066] Step P2: Control the optical path adjustment device 20 to translate the laser Re so that the beam center of the laser Re coincides with the optical axis of the objective lens 300. Specifically, the optical path adjustment device 20 can translate the laser Re. The first translation mechanism 211 can control the translation of the laser Re in the first direction X, and the second translation mechanism 212 can control the translation of the laser Re in the second direction Y.

[0067] Step P11: Control the lifting and lowering of the lifting sample stage 10 and obtain a first image with a focused light spot B1 from the imaging device 40. The focused light spot B1 is the light spot when the laser Re is in a focused state.

[0068] Figure 6 A schematic diagram of the optical path of the laser beam provided by the present invention when the center of the laser beam deviates from the optical axis of the objective lens. Figure 7 The position relationship diagram of the focus spot in the coordinate plane provided by the present invention. Figure 1-7 It can be seen that in the initial state, the laser light Re from the optical path adjustment device 20 and the optical axis C of the objective lens 300 may deviate in the first direction X and / or the second direction Y, or the two may be non-parallel and have a certain angle, or both situations may occur. Figure 6 Take the optical path in plane XZ as an example for explanation. The optical path in plane YZ refers to the optical path in plane XZ and will not be described in detail. Figure 6 and Figure 7It can be seen that the laser Re is converged to the front focal plane of the objective lens 300 after passing through the objective lens 300; at this time, the lifting sample stage 10 is located at the first height H1, and the laser Re irradiates the surface of the sample 100 to form a focused light spot B1. At this time, the image of the sample 100 that can be obtained by the imaging module 40 has the focused light spot B1 of the laser Re. The image center T of the sample 100 is the projection of the optical axis C of the objective lens 300 on the coordinate plane S0. It should be noted that the image center T of the sample 100 remains unchanged when the lifting sample stage 10 is located at any height. The coordinate plane S0 is perpendicular to the lifting direction of the lifting sample stage 100 (i.e., the third direction Z), that is, the coordinate plane S0 is parallel to the plane XY. When the lifting sample stage 10 is lifted and lowered along the third direction Z and is located at different heights, the laser Re is in different degrees of focusing state, and the size and position of the light spot formed by irradiating the surface of the sample 100 are different. At the same time, since the laser Re is inclined to the coordinate plane S0 after passing through the objective lens 300, the center of the light spot of the laser Re corresponds to different sample heights, and the coordinates projected in the coordinate plane S0 are different. When the lifting sample stage 10 is at the first height H1, the laser Re is in a focused state, the spot of the laser Re is a focused spot, and the image of the sample 100 acquired by the imaging module 40 is a first image. Correspondingly, when the lifting sample stage 10 is at the second height, the laser Re is in a defocused state, the spot of the laser Re is a defocused spot, and the image of the sample 100 acquired by the imaging module 40 is a second image. The first height H1 is not equal to the second height. Figure 6 In the illustrated embodiment, the radius of the light entrance hole 303 of the objective lens 300 is about 1-3 mm, and the diameter of the laser beam is smaller than the diameter of the light entrance hole 303. Optionally, the diameter of the laser beam is greater than or equal to the diameter of the light entrance hole 303. The distance between the objective lens 300 and the top of the lifting sample stage 10 is about 10-20 mm. The optical path length between the optical path adjustment device 20 and the objective lens 300 is generally more than 1000 mm.

[0069] Step P12: Identify a first coordinate (x1, y1) of the center of the focused light spot B1, and determine whether the absolute value of a first difference ΔN1 between the first coordinate (x1, y1) and a reference coordinate (x0, y0) of the optical axis C of the objective lens 300 is less than a first threshold value Pth1; the first coordinate (x1, y1) is the coordinate of the projection of the center of the focused light spot B1 on a coordinate plane S0, and the reference coordinate (x0, y0) is the coordinate of the projection of the optical axis C of the objective lens 300 on the coordinate plane S0, and the coordinate plane S0 is perpendicular to the lifting direction of the lifting sample stage 10, that is, the third direction Z.

[0070] In an illustrative embodiment, in step P12, the component of the first coordinate (x1, y1) in the first direction X is x1, and the component in the second direction Y is y1; the component of the reference coordinate (x0, y0) in the first direction is x0, and the component in the second direction is y0; the step of "determining whether the absolute value of the first difference ΔN1 between the first coordinate (x1, y1) and a reference coordinate (x0, y0) of the optical axis C of the objective lens 300 is less than a first threshold value Pth1" includes: determining whether |x1-x0| is less than a third threshold value Pth3, and whether |y1-y0| is less than a fourth threshold value Pth4.

[0071] Determining the absolute value |ΔN1| of the first difference ΔN1 between the first coordinate (x1, y1) and the reference coordinate (x0, y0) is to determine the degree of deviation (e.g., distance) between the center of the focused light spot B1 and the image center T, where the coordinates of the image center T are the reference coordinates (x0, y0). In this way, the absolute value |ΔN1| of the first difference ΔN1 representing the degree of deviation between the two is decomposed in the first direction X and the second direction Y, respectively, that is, the absolute value |ΔN1| of the first difference ΔN1 between the first coordinate (x1, y1) and the reference coordinate (x0, y0) has a component of |x1-x0| in the first direction X and a component of |y1-y0| in the second direction Y. The degree of deviation between the center of the focused light spot B1 and the image center T is determined in the first direction X and the second direction Y, respectively, where the first direction X is perpendicular to the second direction Y, so that the above-mentioned degree of deviation can be determined by the difference between the coordinates in a rectangular coordinate system. Optionally, the step of determining whether the absolute value |ΔN1| of the first difference ΔN1 between the first coordinate (x1, y1) and the reference coordinate (x0, y0) is less than the first threshold Pth1 includes: calculating the distance between the first coordinate (x1, y1) and the reference coordinate (x0, y0) as the absolute value |ΔN1| of the first difference ΔN1.

[0072] Step P13: when the absolute value |ΔN1| of the first difference ΔN1 is greater than or equal to the first threshold value Pth1, the optical path adjustment device 20 is controlled according to the first difference ΔN1 so that the absolute value |ΔN1| of the first difference ΔN1 is less than the first threshold value Pth1; when the absolute value |ΔN1| of the first difference ΔN1 is less than the first threshold value Pth1, step P13 is not performed;

[0073] Figure 8 This is a schematic diagram of the optical path of the laser provided by the present invention being parallel to the optical axis of the objective lens. Fig. 9 This is a diagram showing the position relationship between the focused light spot and the defocused light spot in the coordinate plane when the laser provided by the present invention is parallel to the optical axis of the objective lens. Figure 8 The optical path in plane XZ is used as an example for explanation. The optical path in plane YZ refers to the optical path in plane XZ and will not be described in detail. Figure 6-9It can be seen that when the optical path adjustment device 20 controls the inclination angle of the laser Re (i.e., the angle with the optical axis C) to gradually decrease and moves the focused spot, the center of the focused spot B1 gradually approaches the image center T. When the laser Re is parallel to the optical axis C of the objective lens 300, the degree of deviation between the center of the focused spot B1 and the image center T (i.e., the absolute value of the first difference ΔN1 |ΔN1|) is less than the first threshold value Pth1. Therefore, when the absolute value |ΔN1| of the first difference ΔN1 is less than the first threshold value Pth1, the laser Re is parallel to the optical axis C of the objective lens 300. In step P13, if the absolute value |ΔN1| of the first difference ΔN1 is less than the first threshold value Pth1 in the initial state, step P13 is not executed. At this time, after step P12, the laser Re has been parallel to the optical axis C of the objective lens 300.

[0074] Step P13 can be performed independently in the first direction X and the second direction Y. In an exemplary embodiment, step P13 includes: when |x1-x0| is greater than or equal to the third threshold value Pth3, the first angle adjustment mechanism 221 is controlled so that |x1-x0| is less than the third threshold value Pth3; when |y1-y0| is greater than or equal to the fourth threshold value Pth4, the second angle adjustment mechanism 222 is controlled so that |y1-y0| is less than the fourth threshold value Pth4. In this way, the laser Re can be adjusted to be parallel to the optical axis C of the objective lens 300 in the first direction X and the second direction Y respectively.

[0075] How to control the first angle adjustment mechanism 221 to move the focused light spot B1 in the first direction X so that |x1-x0| is less than the third threshold value Pth3, and how to control the second angle adjustment mechanism 222 to move the focused light spot B1 in the second direction Y so that |y1-y0| is less than the fourth threshold value Pth4; a variety of different methods can be used. Optionally, the step of "controlling the first angle adjustment mechanism 221 so that |x1-x0| is less than the third threshold value Pth3" in step P13 includes one of the following steps P131 (method 1.1), step P132 (method 1.2), and step P133 (method 1.3). Optionally, the step of "controlling the second angle adjustment mechanism 222 so that |y1-y0| is less than the fourth threshold value Pth4" in step P13 includes one of the following steps P134 (method 1.4), step P135 (method 1.5), and step P136 (method 1.6).

[0076] Method 1.1 is a real-time measurement method, namely, step P131: controlling the first angle adjustment mechanism 221 to step, and measuring the component x1 of the first coordinate (x1, y1) in the first direction in real time until |x1-x0| is less than the third threshold value Pth3.

[0077] Specifically, during the stepping process of the first angle adjustment mechanism 221, the laser Re will be deflected, thereby causing the focused light spot B1 to move in the first direction X. The component x1 of the first coordinate (x1, y1) in the first direction changes. The first angle adjustment mechanism 221 acquires an image with the focused light spot B1 each time it steps by the first step amount, identifies the component x1 of the first coordinate (x1, y1) of the center of the focused light spot B1 in the first direction, and calculates |x1-x0|. The relationship between the size of |x1-x0| and the third threshold value Pth3 is determined in real time. Stop when the first angle adjustment mechanism 221 steps to make |x1-x0| less than the third threshold value Pth3. Optionally, when determining the stepping direction of the first angle adjustment mechanism 221, perform the first step first, and determine the change of |x1-x0| after the first step. If |x1-x0| increases, the first angle adjustment mechanism 221 steps in the opposite direction to the first step; if |x1-x0| decreases, the first angle adjustment mechanism 221 continues to step in the same direction as the first step.

[0078] Method 1.2 is a method using a pre-stored correspondence relationship, that is, step P132: obtaining a pre-stored first correspondence relationship f1, the first correspondence relationship f1 being the relationship between the first adjustment amount of the first angle adjustment mechanism 221 and x1-x0 relative to the laser alignment state; obtaining the first adjustment amount of the first angle adjustment mechanism 221 according to x1-x0 measured during the laser alignment adjustment and the first correspondence relationship f1; and controlling the first angle adjustment mechanism 221 to adjust the first adjustment amount.

[0079] Specifically, the relationship between the first adjustment amount of the first angle adjustment mechanism 221 and x1-x0 (i.e., the first corresponding relationship f1) is obtained in advance; that is, starting from the laser alignment state, the first angle adjustment mechanism 221 steps by how much the center of the focused light spot B1 can be correspondingly separated from the reference coordinate in the first direction X by how much (i.e., x1-x0). In this way, the first adjustment amount of the first angle adjustment mechanism 221 can be obtained by using x1-x0 measured during the current laser alignment adjustment and the first corresponding relationship f1. Then, the first angle adjustment mechanism 221 can be controlled to step by the first adjustment amount so that |x1-x0| is less than the third threshold value Pth3. At this time, the first corresponding relationship f1 is the relationship between the first adjustment amount of the first angle adjustment mechanism 221 and x1-x0 relative to the laser alignment state.

[0080] Optionally, the first correspondence f1 is a correspondence table or function. It should be noted that the first correspondence f1 can be obtained by measuring in advance on an experimental optical device. The experimental optical device and the optical device currently performing laser alignment adjustment can be the same or different, but the two have a certain correspondence. For example, the optical path of the experimental optical device and the optical device currently performing laser alignment adjustment is the same, but the front focal length of the objective lens is the same or different.

[0081] Method 1.3 adopts a theoretical calculation formula method, that is, step P133: calculate the first angle θ1 between the laser Re and the optical axis C of the objective lens 300 in the first direction X according to x1-x0 measured during the laser collimation adjustment and formula 1, formula 1: θ1=arctan[(x1-x0) / FL], FL is the front focal length of the objective lens 300; control the first angle adjustment mechanism 221 to rotate the laser Re in the first direction X relative to the optical axis C of the objective lens 300 by the first angle θ1.

[0082] Specifically, if Figure 6-9 As shown, the present invention also provides a method for measuring the angle between the laser Re and the optical axis C of the objective lens 300. The method first executes step P110: control the lifting and lowering of the lifting sample stage 10 and obtain a first image with a focused spot B1 from the imaging device 40, and the focused spot B1 is the spot when the laser Re is in a focused state; then execute step P120: identify a first coordinate (x1, y1) of the center of the focused spot B1; and then execute step P130: calculate the first angle θ1 between the laser Re and the optical axis C of the objective lens 300 in the first direction X according to x1-x0 measured during the laser collimation adjustment and formula 1, formula 1: θ1=arctan[(x1-x0) / FL], FL is the front focal length of the objective lens 300. As shown Figure 6-9 Taking the projection on plane XZ as an example, the above method is applicable to the projection of any plane passing through the optical axis C. After measuring the first angle θ1, it can be applied to a variety of application scenarios. For example, adjusting the inclination angle of the laser Re can achieve laser collimation, or achieve the laser Re passing through the objective lens 300 to be incident on the surface of the sample 100 at a set angle.

[0083] Similarly, method 1.4 is a real-time measurement method, that is, step P134: control the second angle adjustment mechanism 222 to step, and measure the component y1 of the first coordinate (x1, y1) in the second direction in real time until |y1-y0| is less than the fourth threshold value Pth4;

[0084] Specifically, during the stepping process of the second angle adjustment mechanism 222, the laser Re will be deflected, thereby causing the focused spot B1 to move in the second direction Y. The component Y1 of the first coordinate (x1, y1) in the second direction changes. Every time the second angle adjustment mechanism 222 steps a second step amount, an image with the focused spot B1 is acquired, the component y1 of the first coordinate (x1, y1) of the center of the focused spot B1 in the second direction is identified, and |y1-y0| is calculated. The relationship between the size of |y1-y0| and the fourth threshold value Pth4 is judged in real time. The second angle adjustment mechanism 222 stops when it steps to make |y1-y0| less than the fourth threshold value Pth4. Optionally, when determining the stepping direction of the second angle adjustment mechanism 222, the first step is performed first, and the change of |y1-y0| after the first step is judged. If |y1-y0| increases, the second angle adjustment mechanism 222 steps in the opposite direction to the first step; if |y1-y0| decreases, the second angle adjustment mechanism 222 continues to step in the same direction as the first step.

[0085] Method 1.5 is a method of using a pre-stored correspondence relationship, that is, step P135: obtaining a pre-stored second correspondence relationship f2, the second correspondence relationship f2 being the relationship between the second adjustment amount of the second angle adjustment mechanism 222 and y1-y0 relative to the laser alignment state; obtaining the second adjustment amount of the second angle adjustment mechanism 222 according to y1-y0 measured during the laser alignment adjustment and the second correspondence relationship f2; and controlling the second angle adjustment mechanism 222 to adjust the second adjustment amount.

[0086] Specifically, the relationship between the second adjustment amount of the second angle adjustment mechanism 222 and y1-y0 (i.e., the second corresponding relationship f2) is obtained in advance; that is, starting from the laser alignment state, the second angle adjustment mechanism 222 steps by how much to correspond to the distance between the center of the focused light spot B1 and the reference coordinate in the second direction Y (i.e., y1-y0). In this way, the second adjustment amount of the second angle adjustment mechanism 222 can be obtained through y1-y0 measured during the current laser alignment adjustment and the second corresponding relationship f2. Then, the second angle adjustment mechanism 222 can be controlled to step the second adjustment amount so that |y1-y0| is less than the fourth threshold value Pth4. At this time, the second corresponding relationship f2 is the relationship between the second adjustment amount of the second angle adjustment mechanism 222 and y1-y0 relative to the laser alignment state.

[0087] Optionally, the second correspondence f2 is a correspondence table or function. It should be noted that the second correspondence f2 can be obtained by measuring in advance on an experimental optical device. The experimental optical device and the optical device currently performing laser alignment adjustment can be the same or different, but the two have a certain correspondence. For example, the optical path of the experimental optical device and the optical device currently performing laser alignment adjustment is the same, but the front focal length of the objective lens is the same or different.

[0088] Method 1.6 is a method using a theoretical calculation formula, i.e., step P136: calculate the second angle θ2 between the laser Re and the optical axis C of the objective lens 300 in the second direction Y according to y1-y0 measured during laser alignment adjustment and formula 2, formula 2: θ2=arctan[(y1-y0) / FL]; control the second angle adjustment mechanism 222 to rotate the laser Re relative to the optical axis C of the objective lens 300 in the second direction Y by the second angle θ2. The specific process of method 1.6 can refer to method 1.3, which will not be repeated here.

[0089] In an illustrative embodiment, the brightness of the focused spot B1 is detected in real time during the process of controlling the first angle adjustment 221 mechanism in executing step P13 so that |x1-x0| is less than a third threshold value Pth3. When the brightness of the focused spot B1 decreases, the first angle adjustment mechanism 221 is stopped and the first translation mechanism 211 is controlled to translate a first preset distance so that the brightness of the focused spot B1 is enhanced. Then, the first angle adjustment mechanism 221 is continued to be controlled so that |x1-x0| is less than a third threshold value Pth3.

[0090] Similarly, in the process of executing step P13, "controlling the second angle adjustment mechanism 222 so that |y1-y0| is less than the fourth threshold value Pth4, the brightness of the focused light spot B1 is detected in real time, and when the brightness of the focused light spot B1 decreases, the second angle adjustment mechanism 222 is stopped and the second translation mechanism 212 is controlled to translate a second preset distance so that the brightness of the focused light spot B1 is enhanced, and then the second angle adjustment mechanism is continued to be controlled so that |y1-y0| is less than the fourth threshold value Pth4.

[0091] Fig.10 A schematic diagram of the process of laser deflection in the first direction provided by the present invention. Fig.10It can be seen that the first angle adjustment 221 mechanism is controlled to step so that the laser Re1 in the initial state deflects a preset angle Δθ1 in the first direction X and then reaches the laser Re2 in the first intermediate state. At this time, the laser Re2 in the first intermediate state irradiates the edge of the light entrance hole 303 of the objective lens 300, and part of its light beam is blocked and fails to enter the light entrance hole 303, and the brightness of the focused light spot B1 will be weakened. When the brightness of the focused light spot B1 is weakened by a preset amplitude (for example, weakened by 50%), the laser stops deflecting. Then the first translation mechanism 211 is controlled to translate a first preset distance ΔD1 so that the brightness of the focused light spot B1 is enhanced. Usually, the brightness of the focused light spot B1 is restored to the original brightness level. Optionally, the first preset distance ΔD1 is set to Φ / 2, where Φ is the diameter of the light entrance hole 303 of the objective lens 300. The translation direction of the laser in the first direction is to move in the direction that increases the brightness of the focused light spot B1, that is, to move in the direction close to the center of the light entrance hole 303. For example, when the laser is deflected, the laser spot B1 moves in the opposite direction of the first direction X, and the direction of the laser translation is to make the laser spot B1 move in the positive direction of the first direction X. In this way, after the laser translates the first preset distance ΔD1 and reaches the second intermediate state of laser Re3, it can all enter the light entrance hole 303. Then continue to control the first angle adjustment mechanism 221 so that |x1-x0| is less than the third threshold value Pth3; when the brightness of the focused spot B1 decreases again during the process, the above steps can be repeated. Fig.10 The process in which the brightness of the focused light spot B1 is weakened by the deflection of the laser Re in the first direction X. The process in which the brightness of the focused light spot B1 is weakened by the deflection of the laser Re in the second direction Y can be referred to as Fig.10 And its description will not be repeated here.

[0092] Step P21: Control the lifting and lowering of the lifting sample stage 10 and obtain a second image with a defocused light spot B2 from the imaging device 40. The defocused light spot B2 is the light spot when the laser Re is in a defocused state.

[0093] like Figure 8 As shown, after step 13, the laser Re is parallel to the optical axis C of the objective lens 300, and the center of the focused spot B1 deviates from the image center T (i.e., the absolute value of the first difference) by less than a first threshold value, and it can be considered that the two are concentric at this time. When the laser Re is in a focused state, the height of the lifting sample stage 10 is a first height H1. With the first height H1 as a reference, move up or down along the third direction Z by a preset distance (e.g., 5 microns or 10 microns) to a second height H2, at which time the laser Re is in a defocused state. If the second height H2 is greater than the first height H1, it is positive defocusing, and if the second height H2 is less than the first height H1, it is negative defocusing.

[0094] Step P22: Identify a second coordinate (x2, y2) of the center of the defocused light spot B2, and determine whether the absolute value of a second difference ΔN2 between the second coordinate (x2, y2) and the reference coordinate (x0, y0) of the optical axis C of the objective lens 300 is less than a second threshold value Pth2; the second coordinate (x2, y2) is the coordinate of the projection of the center of the defocused light spot B2 on the coordinate plane S0.

[0095] In an illustrative embodiment, the component of the second coordinate (x2, y2) in the first direction X is x2, and the component in the second direction Y is y2; the step of "determining whether the absolute value of the second difference ΔN2 between the second coordinate (x2, y2) and the reference coordinate (x0, y0) of the optical axis C of the objective lens 300 is less than a second threshold value Pth2" in step P22 includes: determining whether |x2-x0| is less than a fifth threshold value Pth5, and whether |y2-y0| is less than a sixth threshold value Pth6.

[0096] Step P23: When the absolute value |ΔN2| of the second difference ΔN2 is greater than or equal to the second threshold value Pth2, the optical path adjustment device 20 is controlled according to the second difference ΔN2 so that the absolute value |ΔN2| of the second difference ΔN2 is less than the second threshold value Pth2; when the absolute value of the second difference is less than the second threshold value, step P23 is not performed. The optical path adjustment device 20 controls the translation of the laser Re to move the defocused light spot B2 so that the center of the defocused light spot B2 gradually approaches the image center T.

[0097] Step P23 can be performed independently in the first direction X and the second direction Y. In an exemplary embodiment, step P23 includes: when |x2-x0| is greater than or equal to a fifth threshold value Pth5, controlling the first translation mechanism 211 so that |x2-x0| is less than the fifth threshold value Pth5; when |y2-y0| is greater than or equal to a sixth threshold value Pth6, controlling the second translation mechanism 212 so that |y2-y0| is less than the sixth threshold value Pth6.

[0098] How to control the first translation mechanism 211 to move the defocused light spot B2 in the first direction X so that |x2-x0| is less than the fifth threshold value Pth5, and how to control the second translation mechanism 212 to move the defocused light spot B2 in the second direction Y so that |y2-y0| is less than the sixth threshold value Pth6; a variety of different methods can be used. Optionally, the step of "controlling the first translation mechanism 211 so that |x2-x0| is less than the fifth threshold value Pth5" in step P23 includes one of the following steps P231 (method 2.1), step P232 (method 2.2), and step P233 (method 2.3). Optionally, the step of "controlling the second translation mechanism 212 so that |y2-y0| is less than the sixth threshold value Pth6" in step P23 includes one of the following steps P234 (method 2.4), step P235 (method 2.5), and step P236 (method 2.6).

[0099] Method 2.1 is a real-time measurement method, namely, step P231: controlling the first translation mechanism 211 to step, and measuring the component x2 of the second coordinate (x2, y2) in the first direction X in real time until |x2-x0| is less than the fifth threshold value Pth5.

[0100] Specifically, during the stepping process of the first translation mechanism 211, the laser Re will translate, thereby causing the defocused light spot B2 to move in the first direction X. The component x2 of the second coordinate (x2, y2) in the first direction changes. Each time the first translation mechanism 211 steps a first translation amount, an image with the defocused light spot B2 is acquired, the component x2 of the second coordinate (x2, y2) of the center of the defocused light spot B2 in the first direction is identified, and |x2-x0| is calculated. The relationship between the size of |x2-x0| and the fifth threshold value Pth5 is judged in real time. Stop when the first translation mechanism 211 steps to make |x2-x0| less than the fifth threshold value Pth5. Optionally, when determining the stepping direction of the first translation mechanism 211, the first step is performed first, and the change of |x2-x0| after the first step is judged. If |x2-x0| increases, the first translation mechanism 211 steps in the opposite direction to the first step; if |x2-x0| decreases, the first translation mechanism 211 continues to step in the same direction as the first step.

[0101] Method 2.2 is a method using a pre-stored correspondence relationship, that is, step P232: obtaining a pre-stored third correspondence relationship f3, the third correspondence relationship f3 being the relationship between the first translation amount of the first translation mechanism 211 and x2-x0 relative to the laser alignment state; obtaining the first translation amount of the first translation mechanism 211 according to x2-x0 measured during laser alignment adjustment and the third correspondence relationship f3; and controlling the first translation mechanism 211 to adjust the first translation amount.

[0102] Specifically, the relationship between the first translation amount of the first translation mechanism 211 and x2-x0 (i.e., the third corresponding relationship f3) is obtained in advance; that is, starting from the laser alignment state, the step of the first translation amount can correspond to the distance between the center of the defocused light spot B2 and the reference coordinate in the first direction X (i.e., x2-x0). In this way, the first translation amount of the first translation mechanism 211 can be obtained through x2-x0 measured during the current laser alignment adjustment and the third corresponding relationship f3. Then the first translation mechanism 211 can be controlled to step the first translation amount so that |x2-x0| is less than the fifth threshold value Pth5. At this time, the third corresponding relationship f3 is the relationship between the first translation amount of the first translation mechanism 211 and x2-x0 relative to the laser alignment state. Optionally, the third corresponding relationship f3 is a corresponding table or function. It should be noted that the acquisition of the first corresponding relationship f1 can be obtained by measuring in advance on an experimental optical device.

[0103] Method 2.3 is a method using a theoretical calculation formula, i.e., step P233: calculate the first distance d1 between the laser Re and the optical axis C of the objective lens 300 in the first direction X according to x2-x0 measured during the laser collimation adjustment and formula 3, formula 3: d1=BFL*(x2-x0) / h, BFL is the back focal length of the objective lens 300, h is the difference between the height of the lifting sample stage 10 in the focused state (i.e., the first height H1) and the height of the lifting sample stage 10 in the defocused state (i.e., the second height); control the first translation mechanism 211 to translate the laser Re in the first direction X by a first distance d1.

[0104] Fig.11 This is a schematic diagram of the optical path in which the laser center provided by the present invention coincides with the optical axis of the objective lens. Fig.12 The diagram is a positional relationship diagram of the focused light spot and the defocused light spot in the coordinate plane when the laser center provided by the present invention coincides with the optical axis of the objective lens.

[0105] Specifically, if Figure 8-11 As shown, BFL = Φ / 2tanα, α = arcsin (NA / n). Where Φ is the diameter of the light entrance hole 303 of the objective lens 300, α is the aperture angle of the objective lens 300, NA is the numerical aperture of the objective lens 300, and n is the refractive index of the medium between the objective lens 300 and the sample 100. From Formula 3: d1 = BFL*tan(Δθx) = BFL*(x2-x0) / h = BFL*(x2-x0) / (H1-H2), it can be seen that the translation direction of the first translation mechanism 211 is determined by x2-x0 and H1-H2.

[0106] The present invention also provides a method for measuring the distance between the laser Re parallel to the optical axis C of the objective lens 300 and the optical axis C of the objective lens 300. The method first executes step P210: controls the lifting and lowering of the lifting sample stage 10 and obtains a second image with a defocused spot B2 from the imaging device 40, and the defocused spot B2 is the spot when the laser Re is in a defocused state; then executes step P220: identifies a second coordinate (x2, y2) of the center of the defocused spot B2; and then executes step P230: calculates the first distance d1 between the laser Re and the optical axis C of the objective lens 300 in the first direction X according to x2-x0 measured during the laser collimation adjustment and formula 3, formula 3: d1 = BFL*(x2-x0) / h, BFL is the back focal length of the objective lens, and h is the difference between the height of the lifting sample stage in the focused state and the height of the lifting sample stage in the defocused state. Figure 8-11 Taking the projection on plane XZ as an example, the above method is applicable to the projection of any plane passing through the optical axis C. After measuring the first distance d1, it can be applied to a variety of application scenarios. For example, adjusting the translation position of the laser Re can achieve laser collimation, or achieve the laser Re passing through the objective lens 300 to be incident on the surface of the sample 100 at a set angle.

[0107] Similarly, method 2.4 is a real-time measurement method, namely step P234: control the second translation mechanism 212 to step, and measure the component y2 of the second coordinate (x2, y2) in the second direction Y in real time until |y2-y0| is less than the sixth threshold value Pth6.

[0108] Specifically, during the stepping process of the second translation mechanism 212, the laser Re will translate, thereby causing the defocused light spot B2 to move in the second direction Y. The component y2 of the second coordinate (x2, y2) in the second direction Y changes. Every time the second translation mechanism 212 steps a second translation amount, an image with the defocused light spot B2 is acquired, the component y2 of the second coordinate (x2, y2) of the center of the defocused light spot B2 in the second direction is identified, and |y2-y0| is calculated. The relationship between the size of |y2-y0| and the sixth threshold value Pth6 is judged in real time. The second translation mechanism 212 stops when it steps to make |y2-y0| less than the sixth threshold value Pth6. Optionally, when determining the stepping direction of the second translation mechanism 212, the first step is performed first, and the change of |y2-y0| after the first step is judged. If |y2-y0| increases, the second translation mechanism 212 steps in the opposite direction to the first step; if |y2-y0| decreases, the second translation mechanism 212 continues to step in the same direction as the first step.

[0109] Method 2.5 is a method of using a pre-stored correspondence relationship, that is, step P235: obtaining a pre-stored fourth correspondence relationship f4, the fourth correspondence relationship f4 being the relationship between the second translation amount of the second translation mechanism 212 and y2-y0 relative to the laser alignment state; obtaining the second translation amount of the second translation mechanism 212 according to y2-y0 measured during the laser alignment adjustment and the fourth correspondence relationship f4; and controlling the second translation mechanism 212 to adjust the second translation amount.

[0110] Specifically, the relationship between the second translation amount of the second translation mechanism 212 and y2-y0 (i.e., the fourth corresponding relationship f4) is obtained in advance; that is, starting from the laser alignment state, the second translation amount step can correspond to the distance between the center of the defocused light spot B2 and the reference coordinate in the second direction Y (i.e., y2-y0). In this way, the second translation amount of the second translation mechanism 212 can be obtained through y2-y0 measured during the current laser alignment adjustment and the fourth corresponding relationship f4. Then the second translation mechanism 212 can be controlled to step the second translation amount so that |y2-y0| is less than the sixth threshold value Pth6. At this time, the fourth corresponding relationship f4 is the relationship between the second translation amount of the second translation mechanism 212 and y2-y0 relative to the laser alignment state. Optionally, the fourth corresponding relationship f4 is a corresponding table or function. It should be noted that the fourth corresponding relationship f4 can be obtained by measuring in advance on an experimental optical device.

[0111] Method 2.6 is a method using a theoretical calculation formula, i.e., step P236: calculate the second distance d2 between the laser Re and the optical axis C of the objective lens 300 in the second direction Y according to y2-y0 measured during laser alignment adjustment and formula 4, formula 4: d2=BFL*(y2-y0) / h; control the second translation mechanism 212 to translate the laser Re in the second direction Y by the second distance d2. The specific process of method 2.6 can refer to method 2.3, which will not be repeated here.

[0112] In summary, after step P23, the center of the focused light spot B1 and the center of the defocused light spot B2 both coincide with the image center T. At this time, the beam center of the laser Re in the first direction X and the second direction Y coincides with the optical axis C of the objective lens 300, that is, the collimation of the laser Re is achieved. In step P23, when the absolute value |ΔN2| of the second difference ΔN2 is less than the second threshold value Pth2, step P23 is not performed. At this time, the collimation of the laser Re has been achieved after step P22.

[0113] In an exemplary embodiment, one or more of the first threshold Pth1, the second threshold Pth2, the third threshold Pth3, the fourth threshold Pth4, the fifth threshold Pth5 and the sixth threshold Pth6 are selected from 0.5-3 microns, for example 0.5 microns, 1 micron, 1.5 microns, 2 microns, 2.5 microns, 3 microns.

[0114] Fig.13 This is a schematic diagram of the structure of a laser alignment adjustment system provided by the present invention. Figure 1 , Figure 2 and Fig.13 It can be seen that the optical device includes an optical path adjustment device 20, an imaging device 40, an objective lens 30, and a lifting sample stage 10; a laser Re is irradiated onto a sample 100 on the lifting sample stage 10 after passing through the optical path adjustment device 20 and the objective lens 30, and the imaging device 40 can image the sample 100; the laser alignment adjustment system 50 includes:

[0115] A first image acquisition module 511, used to control the lifting and lowering of the lifting sample stage 10 and to acquire a first image having a focused light spot B1 from the imaging device 40, where the focused light spot B1 is the light spot when the laser Re is in a focused state;

[0116] A first identification and judgment module 512 is used to identify a first coordinate (x1, y1) of the center of the focused light spot B1, and to judge whether the absolute value of a first difference ΔN1 between the first coordinate (x1, y1) and a reference coordinate (x0, y0) of the optical axis C of the objective lens 300 is less than a first threshold value Pth1; the first coordinate (x1, y1) is the coordinate of the projection of the center of the focused light spot B1 on a coordinate plane S0, the reference coordinate (x0, y0) is the coordinate of the projection of the optical axis C of the objective lens 300 on the coordinate plane S0, and the coordinate plane S0 is perpendicular to the lifting direction of the lifting sample stage 10;

[0117] a first control execution module 513, configured to control the optical path adjustment device 20 according to the first difference ΔN1 so that the absolute value of the first difference ΔN1 |ΔN1| is less than the first threshold value Pth1 when the absolute value of the first difference ΔN1 |ΔN1| is greater than or equal to the first threshold value Pth1; and not perform any operation when the absolute value of the first difference ΔN1 |ΔN1| is less than the first threshold value Pth1;

[0118] A second image acquisition module 521, used to control the lifting and lowering of the lifting sample stage 10 and to acquire a second image having a defocused light spot B2 from the imaging device 40, where the defocused light spot B2 is the light spot when the laser Re is in a defocused state;

[0119] a second identification and determination module 522, for identifying a second coordinate (x2, y2) of the center of the defocused light spot B2, and determining whether an absolute value of a second difference ΔN2 between the second coordinate (x2, y2) and the reference coordinate (x0, y0) of the optical axis C of the objective lens 300 is less than a second threshold value Pth2; the second coordinate (x2, y2) is the coordinate of the projection of the center of the defocused light spot B2 on the coordinate plane S0;

[0120] A second control execution module 523 is used to control the optical path adjustment device 20 according to the second difference ΔN2 so that the absolute value of the second difference ΔN2 |ΔN2| is less than the second threshold value Pth2 when the absolute value of the second difference ΔN2 |ΔN2| is greater than or equal to the second threshold value Pth2; when the absolute value of the second difference ΔN2 is less than the second threshold value, no operation is performed.

[0121] In an exemplary embodiment, the optical device includes an optical path adjustment device 20 and an objective lens 30, and a laser Re passes through the optical path adjustment device 20 and then passes through the objective lens 30; the laser alignment adjustment system 50 includes:

[0122] a first control module 51, used to control the optical path adjustment device 20 to change the inclination angle of the laser Re so that the laser Re is parallel to the optical axis of the objective lens 300; and

[0123] A second control module 52 is used to control the optical path adjustment device 20 to translate the laser Re so that the beam center of the laser Re coincides with the optical axis of the objective lens 300 .

[0124] In an exemplary embodiment, the optical device further includes an imaging device 40 and a lifting sample stage 10; the laser Re is irradiated onto a sample 100 on the lifting sample stage 10 after passing through the optical path adjustment device 20 and the objective lens 30, and the imaging device 40 can image the sample 100; the first control module 51 also includes the above-mentioned first image acquisition module 511, the first recognition and judgment module 512, and the first control execution module 513. The second control module 52 also includes the above-mentioned second image acquisition module 521, the second recognition and judgment module 522, and the second control execution module 523.

[0125] The present invention also provides an optical device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the above-mentioned laser alignment adjustment method when executing the computer program.

[0126] The present invention also provides a computer-readable storage medium, which stores a computer program. When the computer program is executed by a processor, the steps of the above-mentioned laser alignment adjustment method are implemented.

[0127] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is any such actual relationship or order between these entities or operations. Moreover, the term "include", "comprise" or any other variant thereof is intended to cover non-exclusive inclusion, so that the process, method, article or equipment including a series of elements includes not only those elements, but also includes other elements that are not clearly listed, or also includes elements inherent to such process, method, article or equipment. In the present disclosure, the numeral "one" before a noun is only a prefix when the noun first appears, and does not limit the number of the noun. In the absence of more restrictions, the elements defined by the sentence "including one..." do not exclude the existence of other identical elements in the process, method, article or equipment including the elements. In the absence of more restrictions, "parallel" is included in the basic parallelism within the error range, and "vertical" is included in the basic verticality within the error range. In the absence of more restrictions, "and / or" represents one or two of the two elements before and after; for example, A and / or B, including three cases, i.e. A, B, A and B. In the absence of further restrictions, the sequence numbers of the steps in the present disclosure do not limit the execution order of the steps. In the present disclosure, unless otherwise specified, the laser spot refers to the spot formed when the laser passes through the objective lens and irradiates the sample.

[0128] Although the content of the present invention has been described in detail through the above preferred embodiments, it should be appreciated that the above description should not be considered as a limitation of the present invention. After reading the above content, it will be apparent to those skilled in the art that various modifications and substitutions of the present invention will occur. Therefore, the protection scope of the present invention should be limited by the appended claims.

Claims

1. A laser alignment adjustment method for an optical device, characterized in that: The optical device comprises an optical path adjustment device and an objective lens, and a laser passes through the objective lens after passing through the optical path adjustment device; the method comprises the following steps: Step P1: controlling the optical path adjustment device to change the inclination angle of the laser so that the laser is parallel to the optical axis of the objective lens; and Step P2: Control the optical path adjustment device to translate the laser so that the center of the laser beam coincides with the optical axis of the objective lens.

2. A laser alignment adjustment system for an optical device, characterized in that: The optical device comprises an optical path adjustment device and an objective lens, and a laser passes through the objective lens after passing through the optical path adjustment device; the laser alignment adjustment system comprises: a first control module, used for controlling the optical path adjustment device to change the inclination angle of the laser so that the laser is parallel to the optical axis of the objective lens; and A second control module is used to control the optical path adjustment device to translate the laser so that the center of the laser beam coincides with the optical axis of the objective lens.

3. An optical device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the steps of the laser alignment adjustment method according to claim 1 are implemented.

4. An optical device, characterized in that: include: An optical path adjustment device, an imaging device, an objective lens, a lifting sample stage and a laser alignment adjustment system; A laser is irradiated onto a sample on the lifting sample stage after passing through the optical path adjustment device and the objective lens, and the imaging device can image the sample; the laser alignment adjustment system is the laser alignment adjustment system according to claim 2.

5. The optical device according to claim 4, characterized in that The optical path adjustment device comprises: a first translation mechanism capable of controlling the laser to translate along a first direction; a second translation mechanism capable of controlling the laser to translate along a second direction, wherein the second direction intersects the first direction and is parallel to the coordinate plane; a first angle adjustment mechanism capable of controlling the laser to deflect in the first direction; A second angle adjustment mechanism can control the laser to deflect in the second direction; the lifting direction of the lifting sample stage is a third direction movement, and the third direction is perpendicular to the first direction and the second direction.

6. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the steps of the laser alignment adjustment method according to claim 1 are implemented.

7. A method for measuring the angle between a laser and an optical axis of an objective lens, wherein the laser is converged to a front focal plane of the objective lens after passing through the objective lens, characterized in that: The method comprises: Step P110: controlling a lifting sample stage to move up and down and acquiring a first image having a focused light spot from an imaging device, wherein the focused light spot is a light spot when the laser is in a focused state; Step P120: Identify a first coordinate of the center of the focused light spot; Step P130: Obtain a first angle θ1 between the laser and the optical axis of the objective lens in a first direction according to Formula 1, Formula 1: θ1=arctan[(x1-x0) / FL], where FL is the front focal length of the objective lens, x1 is the component of the first coordinate in the first direction, x0 is the component of a reference coordinate in the first direction, and the reference coordinate is the coordinate of the projection of the optical axis of the objective lens on a coordinate plane, and the coordinate plane is perpendicular to the optical axis of the objective lens.

8. A method for measuring the distance between a laser and an optical axis of an objective lens, wherein the laser is parallel to the optical axis of the objective lens, and the laser is converged to a front focal plane of the objective lens after passing through the objective lens, characterized in that: The method comprises: Step P210: controlling a lifting sample stage to move up and down and acquiring a second image with a defocused light spot from an imaging device, wherein the defocused light spot is a light spot when the laser is in a defocused state; Step P220: Identify a second coordinate of the center of the defocused light spot; Step P230: Obtain a first distance d1 between the laser and the optical axis of the objective lens in a first direction according to Formula 3, Formula 3: d1 = BFL*(x2-x0) / h, BFL is the back focal length of the objective lens, h is the difference between the height of the lifting sample stage in a focused state and the height of the lifting sample stage in a defocused state, x2 is the component of the second coordinate in the first direction, x0 is the component of a reference coordinate in the first direction, the reference coordinate is the coordinate of the projection of the optical axis of the objective lens on a coordinate plane, and the coordinate plane is perpendicular to the optical axis of the objective lens.

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