Laser confocal detection system

Abstract

The invention provides a laser confocal detection system, and the system comprises a laser vibration measurement module which is used for collecting the vibration information of a detected target in the direction of an optical axis; the microscopic optical imaging module is used for detecting a laser signal reflected by the detected target and performing confocal microscopic imaging by using the laser signal to obtain image information of the detected target; the motion control displacement table is used for bearing a measured target; the upper computer is connected with the laser vibration measurement module, the microscopic optical imaging module and the motion control displacement table and used for controlling the laser vibration measurement module, the microscopic optical imaging module and the motion control displacement table. And performing data analysis processing on the vibration information of the measured target along the optical axis direction acquired by the laser vibration measurement module and the image information of the measured target acquired by the microscopic optical imaging module. Compared with the prior art, the laser confocal detection system can combine laser vibration measurement and microscopic optical imaging, and vibration measurement and imaging observation of a micro-nano-level measured target in the optical axis direction are achieved.

Description

Technical Field

[0001] The present disclosure relates to the field of laser vibrometer technology, and in particular to a laser confocal detection system. Background Art

[0002] As the market share of micro-electromechanical system-related products such as semiconductor devices and electronic chips increases, performance tests such as natural frequency detection and modal analysis of corresponding components are gradually gaining attention in related fields. The ability to accurately measure the three-dimensional profile and three-dimensional vibration data of micro-nano products within a certain field of view and to complete the vibration modal analysis and topographic image presentation of the corresponding area is of great significance to the actual industrial production of micro-nano components and online quality monitoring.

[0003] Modal analysis is an important method for studying the dynamic characteristics of structures. It can usually describe structures based on modal parameters such as natural frequency, damping, and vibration shape. With the popularization and deepening of modal analysis technology in engineering fields such as fault diagnosis, response prediction, and structural optimization design, the demand for modal analysis technology in industries such as machinery, automobiles, aerospace, precision manufacturing, and civil engineering is becoming increasingly urgent. Since the modal parameters required for modal analysis are often determined by data obtained through experimental modal analysis, a simple and high-precision experimental modal measurement technology has become the key to modal analysis.

[0004] Optical coherence detection of vibration has now been developed to a relatively complete level. The system is a laser confocal detection system that combines multiple technologies such as heterodyne laser Doppler testing method, microscopic imaging method, white light stroboscopic vertical axis in-plane vibration measurement method, dual-mirror scanning control method, image sharpness peak algorithm and high-speed modal detection method. After the outgoing beam of the laser heterodyne system is shaped, it is coupled to the microscopic imaging optical path through the galvanometer control module to realize laser confocalization; then, the traditional white light source is replaced by a stroboscopic light source combined with a high-speed camera to complete rapid shooting, and the vibration detection in the vertical axis plane is realized through the in-plane feature analysis algorithm; at the same time, the dual galvanometer scanning and the precision Z-axis control module respectively realize the in-plane laser scanning and the laser depth direction focusing test; further, the image sharpness peak algorithm is used to analyze the Z-axis motion size to realize the focus point depth measurement, so as to completely restore the morphological information with depth at all scanned locations; in addition, the heterodyne signal high-speed demodulation module is not only used for the restoration of the on-axis vibration signal, but also can send excitation to the target to be measured on the carrier platform, so as to fully analyze the vibration mode of the micro-electromechanical device; finally, the functions are integrated into the host computer through the gateway, and the interaction and control are completed through the host.

[0005] The 3D morphology restoration and micro-vibration modal detection technologies currently mainly include the following methods:

[0006] A method for restoring three-dimensional morphology based on color confocal parallel measurement by image processing is disclosed in the patent document with publication number CN112734916A. The invention provides a method for restoring three-dimensional morphology based on color confocal parallel measurement by image processing. The algorithm first performs target extraction and image stitching on multiple images obtained by the line scanning parallel color confocal system to obtain the stitched image information required for processing; secondly, the centroid connected area of ​​each measured point is obtained through morphological processing and centroid extraction algorithm; finally, the centroid connected area of ​​each measured point in the stitched image is converted from "H value to height", and the height of the corresponding measured point is obtained according to the H value, and then the interpolation fitting algorithm is combined to realize the reconstruction of the three-dimensional morphology of the object surface. The invention is mainly based on the color confocal parallel measurement three-dimensional morphology restoration method of image processing, and is improved, but the method has low processing efficiency in the process of morphology restoration, and is easily affected by stray light and out-of-focus light, and the measurement accuracy is low.

[0007] A patent document with publication number CN116595344A discloses a signal reconstruction method and device for visual structural vibration mode recognition under environmental excitation, which obtains the source image of the structure to be tested, extracts the displacement signal of the region of interest of the structure to be tested by template matching method combined with sub-pixel technology according to the region of interest of several frames of source images; reconstructs the displacement signal to obtain a reconstructed displacement signal, and obtains a reconstructed acceleration signal according to the reconstructed displacement signal; obtains the vibration mode of the region of interest according to the acceleration signal by using natural excitation technology combined with an intrinsic system implementation algorithm; repeats the above steps to obtain the vibration modes of all regions of interest in the source image of the structure to be tested, and splices them to obtain the vibration mode of the structure to be tested. However, this technical solution is not only relatively limited in applicability, but also has a low amplitude resolution, and cannot achieve high-precision measurement at the micro-nano level.

[0008] A patent document with publication number CN116086350A discloses a method, system and application of high-precision microscopic three-dimensional morphology scanning with large depth of field. The method includes: establishing an imaging model based on the principle of intersection line imaging; obtaining the depth direction information and object plane size information of the two dimensions of the acquired image according to the imaging model, and deriving the conversion equation between the image plane and the object plane; calibrating the parameters in the system object-image relationship equation through experiments; using a line laser to scan the object, and calculating the spatial position coordinates of the sampling point through the calibration results to complete the three-dimensional reconstruction. This method is mainly based on structured light three-dimensional microscopic measurement technology. Although the test system has a simple structure, low cost, easy maintenance and high test efficiency, its measurement accuracy is low and it is only suitable for three-dimensional morphology measurement of macroscopic objects. Summary of the invention

[0009] In view of the above-mentioned shortcomings of the related art, an object of the present disclosure is to provide a laser confocal detection system to solve the problems in the related art.

[0010] The present disclosure provides a laser confocal detection system, comprising: a laser vibration measurement module, which is used to collect vibration information of a measured target along an optical axis direction by using Doppler laser vibration measurement technology; a microscopic optical imaging module, which is coupled to the laser vibration measurement module and is used to detect a laser signal reflected by the measured target, and to perform confocal microscopic imaging by using the laser signal to obtain image information of the measured target within an imaging object plane; a motion control displacement stage, which is used to carry the measured target and drive the measured target to move; and a host computer, which is connected to the laser vibration measurement module, the microscopic optical imaging module, and the motion control displacement stage and is used to control the laser vibration measurement module, the microscopic optical imaging module, and the motion control displacement stage to perform data analysis and processing on the vibration information of the measured target along the optical axis direction collected by the laser vibration measurement module and the image information of the measured target collected by the microscopic optical imaging module.

[0011] In some examples, the laser vibration measurement module includes: a heterodyne coherent optical path device, including: a laser and a heterodyne coherent module; the laser is used to generate detection light; the heterodyne coherent module includes a measurement optical path and a reference optical path separated from each other, which are used to divide the detection light of the laser into a measurement light propagating along the measurement optical path and a reference light propagating along the reference optical path; a double galvanometer device is arranged along the measurement optical path, which is used to reflect the measurement light to form a measurement light beam incident on the target to be measured, and to reflect the echo light reflected from the target to be measured and transmit it to the heterodyne coherent module, so that the heterodyne coherent module interferes with the echo light and the reference light to form an electrical detection signal for coherent detection; a signal restoration device is connected to the heterodyne coherent optical path device and the host computer, which is used to restore the vibration output by the heterodyne coherent optical path device and transmit it to the host computer, and the host computer measures the vibration data along the optical axis direction through a detection algorithm.

[0012] In some examples, the heterodyne coherent module includes: a beam splitter, a polarization beam splitter, a laser shaping lens group, a beam combiner, and a photodetector; the beam splitter is used to split the detection light of the laser into measurement light and reference light in a certain proportion; the polarization beam splitter is used to transmit the measurement light emitted by the beam splitter to the laser shaping lens group and to reflect the echo light returned from the laser shaping lens group; the laser shaping lens group is used to shape the measurement light emitted by the polarization beam splitter and to shape the returned echo light; the beam combiner is used to interfere the echo light reflected by the polarization beam splitter with the reference light emitted by the beam splitter to form an interference light signal for coherent detection; the photodetector is used to perform photoelectric conversion on the interference light signal output by the beam combiner to form an electrical detection signal with vibration information.

[0013] In some examples, the laser shaping lens assembly includes: a concave lens, disposed on the light-emitting side of the polarization beam splitter; and a convex lens, disposed on the light-emitting side of the concave lens, wherein the optical axis of the convex lens is coaxial with the optical axis of the concave lens.

[0014] In some examples, the heterodyne coherent module further includes: a reflector and a frequency shifter disposed in the reference optical path; the reflector is used to reflect the reference light emitted by the beam splitter; and the frequency shifter is used to perform frequency shift processing on the reference light reflected by the reflector.

[0015] In some examples, the dual galvanometer device includes: a first galvanometer, arranged along a first axis; a second galvanometer, arranged along a second axis; the first axis and the second axis form an imaging object plane perpendicular to the optical axis; and a galvanometer control module, used to control the first galvanometer to deflect along the first axis and / or control the second galvanometer to deflect along the second axis.

[0016] In some examples, the galvanometer control module includes: a galvanometer rotation motor and a galvanometer controller, the galvanometer rotation motor is connected to the first galvanometer and the second galvanometer, the galvanometer controller is connected to the host computer and the galvanometer rotation motor, and is used to control the galvanometer rotation motor to drive one or both of the first galvanometer and the second galvanometer for deflection according to the instructions of the host computer; or, the galvanometer control module includes: a first galvanometer rotation motor, a second galvanometer rotation motor, and a galvanometer controller, the first galvanometer rotation motor is connected to the first galvanometer, the second galvanometer rotation motor is connected to the second galvanometer, the galvanometer controller is connected to the host computer, the first galvanometer rotation motor, and the second galvanometer rotation motor, and is used to control the first galvanometer rotation motor to drive the first galvanometer for deflection and / or control the second galvanometer rotation motor to drive the second galvanometer for deflection according to the instructions of the host computer.

[0017] In some examples, the signal restoration device includes: a filtering module, which is used to filter the electrical detection signal output by the heterodyne coherent optical path device; a signal restoration module, which is connected to the filtering module, and is used to restore the electrical detection signal after filtering by the filtering module and transmit it to a host computer.

[0018] In some examples, the signal restoration device further includes: an excitation module, configured to generate an excitation signal and output the excitation signal to the target under test.

[0019] In some examples, the microscopic optical imaging module includes: a single-wavelength reflector, a stroboscopic light source, a microscope objective lens group, an imaging focusing lens, and an imaging camera; the single-wavelength reflector is used to reflect the measurement light emitted by the laser vibration measurement module, reflect the echo light reflected by the target to be measured, and transmit the imaging light reflected by the target to be measured; the stroboscopic light source provides stroboscopic light; the microscope objective lens group is arranged between the single-wavelength reflector and the target to be measured, and is used to focus the measurement light emitted after being reflected by the single-wavelength reflector on the target to be measured; the imaging focusing lens is arranged between the single-wavelength reflector and the imaging camera, and is used to focus the imaging light emitted after being transmitted by the single-wavelength reflector on the imaging camera; the imaging camera is connected to the host computer, and is used to transmit images at different times to the host computer, and the host computer measures the in-plane vibration data through a detection algorithm.

[0020] In some examples, the microscope optical imaging module also includes: a semi-transmitter and a semi-reflector, disposed between the single-wavelength reflector and the imaging focusing lens, for reflecting the stroboscopic light so that the stroboscopic light is transmitted through the single-wavelength reflector to the target to be measured and transmitting the imaging light reflected by the target to be measured so as to be transmitted to the imaging camera through the imaging focusing lens.

[0021] In some examples, the single-wavelength reflector is a single-wavelength reflector, the semi-transparent reflector is a semi-transparent mirror, the single-wavelength reflector and the semi-transparent mirror are both incident at a 45° angle, the single-wavelength reflector is arranged along a first axis and the semi-transparent mirror is arranged along a second axis, or the single-wavelength reflector is arranged along the second axis and the semi-transparent mirror is arranged along the first axis.

[0022] In some examples, the motion-controlled translation stage is a three-dimensional translation stage, which is controlled by the host computer to drive the target to be measured to move in a three-dimensional space formed by a first axis, a second axis, and an optical axis; or, the motion-controlled translation stage is controlled by the host computer to drive the target to be measured to move in an imaging object plane formed by the first axis and the second axis and to drive the microscopic optical imaging module to move on the optical axis.

[0023] As described above, the present disclosure provides a laser confocal detection system, including: a laser vibration measurement module, which uses Doppler laser vibration measurement technology to collect vibration information of the target to be measured along the optical axis; a microscopic optical imaging module, which is used to detect the laser signal reflected by the target to be measured, and use the laser signal to perform confocal microscopic imaging to obtain image information of the target to be measured; a motion control displacement stage, which is used to carry the target to be measured; a host computer, which is connected to the laser vibration measurement module, the microscopic optical imaging module, and the motion control displacement stage, and is used to control the laser vibration measurement module, the microscopic optical imaging module, and the motion control displacement stage, and performs data analysis and processing on the vibration information of the target to be measured along the optical axis direction collected by the laser vibration measurement module and the image information of the target to be measured collected by the microscopic optical imaging module. Compared with the related art, the laser confocal detection system disclosed in the present disclosure can combine laser vibration measurement and microscopic optical imaging to achieve vibration measurement and imaging observation of the target to be measured in the optical axis direction at the micro-nano level. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 Shown is a block diagram of a laser confocal detection system in one embodiment of the present disclosure.

[0025] Figure 2 Shown is a schematic structural diagram of a laser confocal detection system in one embodiment of the present disclosure.

[0026] Figure 3 Display as Figure 2 A schematic structural diagram of a dual galvanometer device in one embodiment. DETAILED DESCRIPTION

[0027] The following is an explanation of the embodiments of the present disclosure by specific examples, and those skilled in the art can easily understand other advantages and effects of the present disclosure from the information disclosed by the present disclosure. The present disclosure can also be implemented or applied through other different specific embodiments, and the details in the present disclosure can also be modified or changed in various ways according to different viewpoints and application modules without departing from the spirit of the present disclosure. It should be noted that the embodiments in the present disclosure and the features in the embodiments can be combined with each other without conflict.

[0028] The following is a detailed description of the embodiments of the present disclosure with reference to the accompanying drawings so that those skilled in the art can easily implement the present disclosure. The present disclosure can be embodied in many different forms and is not limited to the embodiments described herein.

[0029] In the representations of the present disclosure, the reference terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" and the like mean that the specific features, structures, materials or characteristics represented in conjunction with the embodiment or example are included in at least one embodiment or example of the present disclosure. Moreover, the specific features, structures, materials or characteristics represented may be combined in any one or a group of embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine different embodiments or examples represented in the present disclosure and the features of different embodiments or examples, unless they are mutually contradictory.

[0030] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the representation of the present disclosure, "a group" means two or more, unless otherwise clearly and specifically defined.

[0031] In order to clearly describe the present disclosure, components not related to the description are omitted, and the same reference numerals are given to the same or similar components throughout the specification.

[0032] Throughout the specification, when a device is said to be "connected" to another device, this includes not only the case of "direct connection" but also the case of "indirect connection" by placing other elements therebetween. In addition, when a device is said to "include" a certain component, unless otherwise stated, it does not exclude other components, but means that other components may be included.

[0033] Although the terms first, second, etc. are used to represent various elements in this article in some examples, these elements should not be limited by these terms. These terms are only used to distinguish one element from another element. For example, the first interface and the second interface, etc. are represented. Moreover, as used in this article, the singular forms "one", "one" and "the" are intended to also include plural forms, unless there is an opposite indication in the context. It should be further understood that the terms "comprising" and "including" indicate that there are the described features, steps, operations, elements, modules, projects, kinds, and / or groups, but do not exclude the existence, occurrence or addition of one or a group of other features, steps, operations, elements, modules, projects, kinds, and / or groups. The terms "or" and "and / or" used herein are interpreted as inclusive, or mean any one or any combination. Therefore, "A, B or C" or "A, B and / or C" means "any of the following: A; B; C; A and B; A and C; B and C; A, B and C". Only when the combination of elements, functions, steps or operations is inherently mutually exclusive in some way, will there be an exception to this definition.

[0034] The technical terms used herein are only used to refer to specific embodiments and are not intended to limit the present disclosure. The singular form used herein also includes the plural form unless the sentence clearly indicates the contrary meaning. The meaning of "including" used in the specification is to specify specific characteristics, regions, integers, steps, operations, elements and / or components, and does not exclude the existence or addition of other characteristics, regions, integers, steps, operations, elements and / or components.

[0035] Although not defined differently, all terms, including technical and scientific terms used herein, have the same meaning as those generally understood by those skilled in the art to which the present disclosure belongs. Terms defined in commonly used dictionaries are additionally interpreted as having meanings consistent with relevant technical literature and the message of the present disclosure, and shall not be overly interpreted as ideal or very formal meanings unless defined.

[0036] In the relevant laser vibration measurement technology, during the vibration measurement process, there will be signals scattered by the emitted laser at the end face of the lens, the end face of the optical fiber, and the structural parts, which will be coupled back into the coherent optical path. Since such signals are not scattered echo signals of the measured target but echo signals inside the system and do not carry Doppler signals, this greatly affects the signal-to-noise ratio and effect of laser vibration measurement. In view of this, a laser confocal detection system is provided in the embodiment of the present disclosure, the laser confocal detection system includes a heterodyne coherent optical path module and a transceiver optical lens module, the heterodyne coherent optical path module includes a coupled laser and a heterodyne coherent optical path chip, the spatial optical path is more integrated and more stable than the optical fiber, and is suitable for small space and high sensitivity scene applications, and the heterodyne coherent optical path system in the heterodyne coherent optical path chip includes a measurement optical path and a reference optical path separated from each other, which can effectively eliminate the scattered echo signal of the chip transmitting end face brought by the coaxial system, and eliminate the intermediate frequency parasitic non-Doppler signal in the system to a certain extent.

[0037] See also Figure 1 , which is a schematic block diagram of the laser confocal detection system disclosed in one embodiment.

[0038] like Figure 1 As shown, the laser confocal detection system disclosed in the present invention includes: a laser vibration measurement module 1, a microscopic optical imaging module 2, a motion control displacement stage 3, and a host computer 4.

[0039] The laser vibration measurement module 1 is used to collect vibration information of the target 90 along the optical axis using Doppler laser vibration measurement technology.

[0040] The microscopic optical imaging module 2 is coupled to the laser vibration measurement module 1 to detect the laser signal reflected by the measured target 90 and use the laser signal to perform confocal microscopic imaging to obtain image information of the measured target 90 in the imaging object plane. The optical axis is perpendicular to the imaging object plane.

[0041] The motion control displacement stage 3 is used to carry the measured object 90 and drive the measured object 90 to move.

[0042] The host computer 4 is connected to the laser vibration measurement module 1, the microscopic optical imaging module 2, and the motion control displacement stage 3, and is used to control the laser vibration measurement module 1, the microscopic optical imaging module 2, and the motion control displacement stage 3, and perform data analysis and processing on the vibration information of the target 90 along the optical axis direction collected by the laser vibration measurement module 1 and the image information of the target 90 collected by the microscopic optical imaging module 2.

[0043] See also Figure 2 , which is a schematic diagram of the structure of the laser confocal detection system disclosed in one embodiment.

[0044] Combination Figure 1 and Figure 2 As shown, the laser confocal detection system disclosed in the present invention includes: a laser vibration measurement module 1, a microscopic optical imaging module 2, a motion control displacement stage 3, and a host computer 4.

[0045] The laser vibration measurement module 1 is used to collect vibration information of the target 90 along the optical axis using Doppler laser vibration measurement technology.

[0046] In some embodiments, the laser vibration measurement module 1 may further include: a heterodyne coherent optical path device 11 , a dual galvanometer device 13 , and a signal restoration device 15 .

[0047] The heterodyne coherent optical path device 11 may include a laser 111 and a heterodyne coherent module.

[0048] The laser 11 is used to generate the detection light. Exemplarily, the laser 11 may be a helium-neon laser, for example, and the detection light generated by the laser may be a 632.8 nm line laser, in the red part of the visible spectrum, but not limited thereto, and the detection light may also be other bands of the visible spectrum or the infrared spectrum, for example, with a wavelength of 1550 nm, 1310 nm, etc.

[0049] In addition, the detection light generated by the laser 11 can be directly input into the heterodyne coherent module, or can be input into the heterodyne coherent module after being coupled with an optical fiber.

[0050] The heterodyne coherent module includes a measurement optical path and a reference optical path separated from each other, and is used to separate the detection light of the laser 11 into a measurement light propagating along the measurement optical path and a reference light propagating along the reference optical path.

[0051] In some embodiments, the heterodyne coherent module may further include a beam splitter 112 , a polarization beam splitter 113 , a laser shaping lens assembly 114 , a beam combiner 115 , and a photodetector 116 .

[0052] The beam splitter 112 is disposed after the output end of the laser 111 to split the detection light output by the laser. Specifically, the beam splitter 112 is used to split the detection light of the laser 111 into a measurement light and a reference light in a certain ratio. In some optional embodiments, the beam splitter 112 can split the measurement light and the reference light at different power ratios. Exemplarily, the ratio of the measurement light to the reference light includes but is not limited to 99:1, 90:10, 80:20 or other ratios. Figure 2 In the illustrated embodiment, the beam splitter 112 may be, for example, a beam splitter mirror.

[0053] The polarization beam splitter 113 is used to transmit the measurement light emitted by the beam splitter 112 to the laser shaping lens group 114 and to reflect the echo light returned from the laser shaping lens group 114. In practical applications, the polarization beam splitter 113 can allow the measurement light split by the beam splitter 112 to pass through and can reflect the returned echo light. Figure 2 In the illustrated embodiment, the polarization beam splitter 113 may be, for example, a polarization beam splitter.

[0054] The laser shaping lens group 114 is used to shape the measurement light emitted by the polarization beam splitter and to shape the returned echo light.

[0055] In certain embodiments, such as Figure 2 As shown, the laser shaping lens group 114 includes: a concave lens 1141 and a convex lens 1143. The concave lens 1141 is arranged on the light-emitting side of the polarization beam splitter 113, and the convex lens 1143 is arranged on the light-emitting side of the concave lens 1141, and the optical axis of the convex lens 1143 is coaxial with the optical axis of the concave lens 1141. In this way, the laser shaping lens group 114 including the concave lens 1141 and the convex lens 1143 shapes the measurement light split by the polarization beam splitter 113 and shapes the returned echo light.

[0056] The laser shaping lens assembly is not limited to Figure 2The structure shown in the figure can still be changed in other ways. In some embodiments, the laser shaping lens group may include: a concave lens, a convex lens, and a reflector. The convex lens is arranged on the output light side of the polarization beam splitter. Specifically, the concave lens is opposite to the output light side of the polarization beam splitter. The convex lens is arranged on the output light side of the concave lens, and the optical axis of the convex lens is perpendicular to the optical axis of the concave lens. The reflector is arranged on the output light side of the concave lens and on the incident light side of the convex lens. In this way, the measurement light split by the polarization beam splitter 113 is shaped by the laser shaping lens group including the concave lens, the reflector, and the convex lens, and the steering of the measurement light is achieved.

[0057] The beam combiner 115 is used to interfere the echo light reflected by the polarization beam splitter 113 with the reference light split by the beam splitter 112 to form an interference light signal for coherent detection. In practical applications, the beam combiner 115 can allow the echo light reflected by the polarization beam splitter 113 to pass through and reflect the reference light. Figure 2 In the illustrated embodiment, the beam combiner 115 may be, for example, a beam combiner mirror.

[0058] In certain embodiments, such as Figure 2 As shown, the heterodyne coherent module further includes a reflector 117 and a frequency shifter 118 disposed in the reference light path between the beam splitter 112 and the beam combiner 115 .

[0059] The reflector 117 is used to reflect the reference light split by the beam splitter 112. Figure 2 In the illustrated embodiment, the reflector 117 may be, for example, a reflector, which can reflect the reference light at 90°. In practical applications, the reflector may be an external reflective prism, an internal reflective prism, or a pentaprism.

[0060] The frequency shifter 118 is used to perform frequency shift processing on the reference light reflected by the reflector 117, and is used to load a heterodyne carrier signal in the reference light. Exemplarily, the frequency shifter 118 can use a single device with different frequency carriers. Exemplarily, the frequency shifter 118 can be obtained by differentially using two or more devices, thereby reducing carrier interference in the Doppler signal frequency spectrum.

[0061] The reference light after the frequency shifting process is outputted to the beam combiner 115 by the frequency shifter 118 .

[0062] The photodetector 116 is used to perform photoelectric conversion on the interference light signal output by the beam combiner 115 to form an electrical detection signal with vibration information.

[0063] In some embodiments, the heterodyne coherent module may further include a signal amplifier (not shown in the figure), which is connected to the photodetector and is used to amplify the electrical detection signal output by the photodetector.

[0064] The dual galvanometer device is arranged along the measuring optical path, and is used to reflect the measuring light to form a measuring light beam incident on the target to be measured, and to reflect the echo light reflected from the target to be measured and transmit it to the heterodyne coherent module, so that the heterodyne coherent module interferes with the echo light and the reference light to form an electrical detection signal for coherent detection.

[0065] See also Figure 3 , displayed as Figure 2 A schematic diagram of the structure of a dual galvanometer device in one embodiment. Figure 2 and Figure 3 The dual galvanometer device 13 may further include: a first galvanometer 131, a second galvanometer 132, and a galvanometer control module.

[0066] The first galvanometer 131 and the second galvanometer 132 are disposed adjacent to each other, wherein the first galvanometer 131 is disposed along a first axis, and the second galvanometer 132 is disposed along a second axis, and the first axis and the second axis form an imaging object plane perpendicular to the optical axis. Figure 3 In the illustrated embodiment, the first galvanometer 131 may be arranged along the X-axis and the second galvanometer 132 may be arranged along the Y-axis, wherein the first galvanometer 131 and the second galvanometer 132 are arranged adjacent to each other. In practical applications, the optical path between the first galvanometer 131 and the second galvanometer 132 should be as small as possible, because the trajectory of the position of the first galvanometer 131 to the second galvanometer 132 after deflection in the X / Y direction is a line in the Y / X direction, that is, there is a difference in the distance between the starting position of the light beam scanning emitted through the galvanometer in the X-axis direction and the Y-axis direction, which will lead to differences in the optical field of view and the emission position in the two directions coupled into the microscopic optical imaging module. By reducing the distance between the first galvanometer 131 and the second galvanometer 132, the influence of the X-axis and Y-axis differences on the aberration of the focused laser spot can be reduced.

[0067] The galvanometer control module is used to control the first galvanometer 131 to deflect along the first axis and / or control the second galvanometer 132 to deflect along the second axis, that is, the galvanometer control module is used to control the first galvanometer 131 to deflect along the X axis and / or control the second galvanometer 132 to deflect along the Y axis.

[0068] In some optional embodiments, the galvanometer control module includes: a galvanometer rotation motor 133 and a galvanometer controller 134, wherein the galvanometer rotation motor 133 is connected to the first galvanometer 131 and the second galvanometer 132, and the galvanometer controller 134 is connected to the host computer 4 and the galvanometer rotation motor 133. The galvanometer controller 134 is used to control the galvanometer rotation motor 133 to drive one or both of the corresponding first galvanometer 131 and the second galvanometer 132 to deflect according to the instructions of the host computer 4. Exemplarily, the galvanometer controller 134 is used to control the galvanometer rotation motor 133 to drive the first galvanometer 131 to deflect along the first axis according to the instructions of the host computer 4. Exemplarily, the galvanometer controller 134 is used to control the galvanometer rotation motor 133 to drive the second galvanometer 132 to deflect along the second axis according to the instructions of the host computer 4. Exemplarily, the galvanometer controller 134 is used to control the galvanometer rotation motor 133 to drive the first galvanometer 131 to deflect along the first axis and to drive the second galvanometer 132 to deflect along the second axis according to the instruction of the host computer 4 .

[0069] In some optional embodiments, the galvanometer control module includes: a galvanometer rotation motor 133 and a galvanometer controller 134, wherein the galvanometer rotation motor 133 is connected to the first galvanometer 131 and the second galvanometer 132, and the galvanometer controller 134 is connected to the host computer 4 and the galvanometer rotation motor 133. The galvanometer controller 134 is used to control the galvanometer rotation motor 133 to drive one or two of the corresponding first galvanometer 131 and the second galvanometer 132 to deflect according to the instructions of the host computer 4. Exemplarily, the galvanometer controller 134 controls the galvanometer rotation motor 133 to drive the first galvanometer 131 to deflect along the first axis according to the instructions of the host computer 4. Exemplarily, the galvanometer controller 134 controls the galvanometer rotation motor 133 to drive the second galvanometer 132 to deflect along the second axis according to the instructions of the host computer 4. Exemplarily, the galvanometer controller 134 controls the galvanometer rotation motor 133 to drive the first galvanometer 131 to deflect along the first axis and to drive the second galvanometer 132 to deflect along the second axis according to the instruction of the host computer 4 .

[0070] In some optional embodiments, the galvanometer control module includes: a first galvanometer rotary motor, a second galvanometer rotary motor, and a galvanometer controller, wherein the first galvanometer rotary motor is connected to the first galvanometer, the second galvanometer rotary motor is connected to the second galvanometer, and the galvanometer controller is connected to the host computer, the first galvanometer rotary motor, and the second galvanometer rotary motor. The galvanometer controller is used to control the first galvanometer rotary motor to drive the first galvanometer to deflect and / or control the second galvanometer rotary motor to drive the second galvanometer to deflect according to the instruction of the host computer. Exemplarily, the galvanometer controller controls the first galvanometer rotary motor to drive the first galvanometer to deflect along the first axis according to the instruction of the host computer. Exemplarily, the galvanometer controller controls the second galvanometer rotary motor to drive the second galvanometer to deflect along the second axis according to the instruction of the host computer. Exemplarily, the galvanometer controller controls the first galvanometer rotary motor to drive the first galvanometer to deflect along the first axis and controls the second galvanometer rotary motor to drive the second galvanometer to deflect along the second axis according to the instruction of the host computer.

[0071] In some optional embodiments, the galvanometer rotary motor (including the first galvanometer rotary motor and the second galvanometer rotary motor) includes a rotary motor and corresponding grating scale encoding hardware, so that the rotation angle accuracy of the corresponding galvanometer (the first galvanometer and the second galvanometer) for deflection can be precisely controlled. In some optional embodiments, the galvanometer rotary motor (including the first galvanometer rotary motor and the second galvanometer rotary motor) includes a rotary motor and corresponding magnetic scale encoding hardware.

[0072] In some optional embodiments, the galvanometer controller may use ARM and other control methods to achieve deflection angle control, receive instructions from the host computer and transmit the instructions to the galvanometer rotating motor (including the first galvanometer rotating motor, the second galvanometer rotating motor) and the encoding part to complete the rotation angle control of the galvanometer (the first galvanometer, the second galvanometer) deflection. In some optional embodiments, the galvanometer controller may use FPGA and other control methods to achieve deflection angle control, receive instructions from the host computer and transmit the instructions to the galvanometer rotating motor (including the first galvanometer rotating motor, the second galvanometer rotating motor) and the encoding part to complete the rotation angle control of the galvanometer (the first galvanometer, the second galvanometer) deflection.

[0073] The signal restoration device is connected to the heterodyne coherent optical path device and the host computer, and is used to restore the vibration output by the heterodyne coherent optical path device and transmit it to the host computer, and the host computer measures the vibration data along the optical axis direction through a detection algorithm.

[0074] In such Figure 2In the illustrated embodiment, the signal restoration device 15 further includes: a filtering module 151 and a signal restoration module 152 .

[0075] The filter module 151 is used to filter the electrical detection signal output by the heterodyne coherent optical path device. That is, the filter module 151 is used to filter the electrical detection signal output by the photodetector 116 in the heterodyne coherent optical path device to reduce the system noise level.

[0076] The signal restoration module 152 is connected to the filtering module 151, and is used to restore the electrical detection signal after filtering by the filtering module 151 and transmit it to the host computer. In some optional embodiments, the signal restoration module 152 can use FPGA to restore the signal.

[0077] In addition, the signal restoration device 15 may also include an excitation module 153, which is used to generate an excitation signal and output the excitation signal to the target 90. In some optional embodiments, the excitation module 153 can generate a certain programmable arbitrary signal as an excitation output to the target 90 through a digital frequency synthesizer DDS, so that the vibration modal analysis is more accurate. Exemplarily, the excitation module 153 is integrated in the signal restoration module 152. Exemplarily, the excitation module 153 is independently set.

[0078] The microscopic optical imaging module 2 is coupled to the laser vibration measurement module 1 to detect the laser signal reflected by the measured target 90 and use the laser signal to perform confocal microscopic imaging to obtain image information of the measured target 90 within the imaging object plane.

[0079] In such Figure 2 In the illustrated embodiment, the microscopic optical imaging module 2 further includes: a single wavelength reflector 21 , a stroboscopic light source 23 , a microscopic objective lens group 25 , an imaging focusing lens 27 , and an imaging camera 29 .

[0080] The single-wavelength reflector 21 is used to reflect the measurement light emitted by the laser vibration measurement module 1 and the echo light reflected by the measured target. The single-wavelength reflector 21 is designed as a reflective device that can only reflect a single-wavelength optical signal, that is, the single-wavelength reflector 21 has an extremely high reflectivity at a specified wavelength of laser light, and the reflectivity can reach 95% to 99%. In practical applications, after the wavelength of the detection light generated by the laser 111 is determined, a single-wavelength reflector 21 of the corresponding wavelength is provided to reflect the measurement light of the wavelength. In some optional embodiments, the single-wavelength reflector 21 can be, for example, a single-wavelength reflector, which is set at an angle of 45° in the measurement light path, so as to achieve a 90° reflection of the measurement light and a 90° reflection of the echo light. Therefore, on the one hand, the single-wavelength reflector 21 can be used to reflect the measurement light output by the dual-vibration mirror device 13 in the laser vibration measurement module 1 and couple it into the microscopic imaging system. On the other hand, the echo light reflected by the target 90 can be reflected and coupled into the heterodyne coherent system.

[0081] The stroboscopic light source 23 provides stroboscopic light. In some optional embodiments, the stroboscopic light source 23 is adjacent to the imaging camera 29. Exemplarily, the stroboscopic light source 23 provides white light. Exemplarily, the stroboscopic light source 23 provides monochromatic light of other wavelengths.

[0082] In some embodiments, the microscopic optical imaging module 2 further includes a semi-transparent reflector 24. The semi-transparent reflector 24 is disposed between the single-wavelength reflector 21 and the imaging focusing lens 27, and is used to reflect the stroboscopic light generated by the stroboscopic light source 23 so that the stroboscopic light is transmitted through the single-wavelength reflector 21 to the measured target 90, and transmit the imaging light reflected by the measured target 90 to the imaging camera 29 through the imaging focusing lens 27. In some optional embodiments, the semi-transparent reflector 24 may be, for example, a semi-transparent mirror, and the ratio of its reflectivity to transmittance may be, for example, 50:50, 55:45, 60:40, 65:35, 70:30, 75:25 or other suitable ratios.

[0083] In particular, in some optional embodiments, the single wavelength reflector in the single wavelength reflector 21 and the semi-transparent mirror in the semi-transparent reflector 24 can be made of flat lenses that are as thin as possible to reduce the influence of flat aberration. The single wavelength reflector in the single wavelength reflector 21 and the semi-transparent mirror in the semi-transparent reflector 24 are both incident at a 45° angle in the optical path, and the two flat lenses can be used for rotation along the X-axis or Y-axis, for example, the single wavelength reflector is deflected along the first axis and the semi-transparent mirror is deflected along the second axis, thereby minimizing the dispersion effect of the lens on the imaging under an appropriate volume, so that the imaging camera 29 can have clearer imaging. In some optional embodiments, the single wavelength reflector in the single wavelength reflector 21 and the semi-transparent mirror in the semi-transparent reflector 24 can be made of flat plates. In some optional embodiments, the single wavelength reflector in the single wavelength reflector 21 and the semi-transparent mirror in the semi-transparent reflector 24 can be made of a beam splitter prism.

[0084] The microscope objective lens group 25 is arranged between the single wavelength reflector 21 and the measured object 90, and is used to focus the measurement light emitted after being reflected by the single wavelength reflector 21 on the measured object 90. In some optional embodiments, the microscope objective lens group 25 is a single objective lens, such as a convex lens. In some optional embodiments, the microscope objective lens group 25 is a plurality of microscope objective lenses of different magnifications connected through an objective lens converter, wherein the objective lens magnification includes multiple magnification objective lenses, and can also be a long working distance objective lens.

[0085] The imaging focusing lens 27 is disposed between the single wavelength reflector 21 and the imaging camera 29 .

[0086] As mentioned above, the single wavelength reflector 21 also transmits the imaging light reflected by the measured object 90. In practical applications, the imaging light reflected by the measured object 90 includes reflected stroboscopic light and a small portion of echo light that is not completely reflected.

[0087] The imaging focusing lens 27 is used to focus the imaging light emitted after being transmitted through the single wavelength reflector 21 on the imaging camera 29. In some embodiments, when the microscopic optical imaging module 2 further includes a semi-transparent reflector 24, the imaging focusing lens 27 is disposed between the semi-transparent reflector 24 and the imaging camera 29, and is used to focus the imaging light emitted after being transmitted through the single wavelength reflector 21 and the semi-transparent reflector 24 on the imaging camera 29.

[0088] The imaging camera 29 is connected to the host computer 4 and is used to transmit images at different times to the host computer 4 , which then measures the in-plane vibration data using a detection algorithm.

[0089] The motion control displacement stage 3 is used to carry the measured object 90 and drive the measured object 90 to move. In some embodiments, the measured object 90 may be, for example, a micro-electromechanical device or a semiconductor device, or a micro-nano-scale product in an electronic chip.

[0090] In some optional embodiments, the motion control displacement stage 3 is a three-dimensional displacement stage, which is controlled by the host computer 4 to drive the measured target 90 to move in a three-dimensional space composed of a first axis (e.g., X-axis), a second axis (e.g., Y-axis), and an optical axis (e.g., Z-axis). In some optional embodiments, the motion control displacement stage 3 is controlled by the host computer 4 to drive the measured target 90 to move in an imaging object plane composed of (e.g., X-axis) and a second axis (e.g., Y-axis) and to drive the microscopic optical imaging module 2 (e.g., the microscopic objective lens group 25 in the microscopic optical imaging module 2) to move on the optical axis. By moving the motion control displacement stage 3 in the imaging object plane, the limitation that the measuring light can only scan within the field of view of the objective lens can be compensated. After the motion control displacement stage 3 drives the measured target 90 to move to complete the vibration measurement, the vibration data of different ranges and the modal analysis conditions can be spliced ​​to meet the detection needs of a wider range.

[0091] When the target 90 to be measured is carried on the motion control displacement stage 3, the measuring light is focused on the surface of the target 90 after passing through the microscope objective group 25. The working distance of the microscope objective group 25 on the Z axis is controlled by the motion control displacement stage 3 and combined with the light spot minimum point peak extraction algorithm to determine the Z axis motion displacement at different scanning points. The displacement data at different points can represent the depth data of the corresponding points of the object to be measured, thereby completing the morphology test.

[0092] The host computer 4 is connected to the laser vibration measurement module 1, the microscopic optical imaging module 2, and the motion control displacement stage 3, and is used to control the laser vibration measurement module 1, the microscopic optical imaging module 2, and the motion control displacement stage 3, and perform data analysis and processing on the vibration information of the target 90 along the optical axis direction collected by the laser vibration measurement module 1 and the image information of the target 90 collected by the microscopic optical imaging module 2.

[0093] In some embodiments, the host computer 4 further includes a gateway integration module 41 and an industrial computer 42. For example, the galvanometer control module in the laser vibration measurement module 1, the stroboscopic light source 23 and the imaging camera 29 in the microscopic optical imaging module 2, and the motion control stage 3 are all connected to the industrial computer 42 through the gateway integration module 41.

[0094] In some embodiments, the industrial computer 42 integrates multiple interface interaction windows, for example, including corresponding setting interfaces for controlling the laser vibration measurement module 1, the microscopic optical imaging module 2, and the motion control displacement stage 3, including time domain and frequency domain diagrams of vibration in the optical axis direction, photos of in-plane vibration at specific moments and internal point vibration data diagrams, two-dimensional imaging diagrams and three-dimensional morphology diagrams, precision motion control displacement stage control interface and modal analysis interface, etc.

[0095] As described above, the present disclosure provides a laser confocal detection system, including: a laser vibration measurement module, which uses Doppler laser vibration measurement technology to collect vibration information of the target to be measured along the optical axis; a microscopic optical imaging module, which is used to detect the laser signal reflected by the target to be measured, and use the laser signal to perform confocal microscopic imaging to obtain image information of the target to be measured; a motion control displacement stage, which is used to carry the target to be measured; a host computer, which is connected to the laser vibration measurement module, the microscopic optical imaging module, and the motion control displacement stage, and is used to control the laser vibration measurement module, the microscopic optical imaging module, and the motion control displacement stage, and performs data analysis and processing on the vibration information of the target to be measured along the optical axis direction collected by the laser vibration measurement module and the image information of the target to be measured collected by the microscopic optical imaging module. Compared with the related art, the laser confocal detection system disclosed in the present disclosure can combine laser vibration measurement and microscopic optical imaging to achieve vibration measurement and imaging observation of the target to be measured in the optical axis direction at the micro-nano level.

[0096] The above embodiments are merely illustrative of the principles and effects of the present disclosure, and are not intended to limit the present disclosure. Anyone familiar with the technology may modify or change the above embodiments without violating the spirit and scope of the present disclosure. Therefore, all equivalent modifications or changes made by those with ordinary knowledge in the technical field without departing from the spirit and technical ideas disclosed in the present disclosure shall still be covered by the protection scope of the present disclosure.

Claims

1. A laser confocal detection system, characterized in that: include: Laser vibration measurement module, used to collect vibration information of the target along the optical axis using Doppler laser vibration measurement technology; A microscopic optical imaging module, coupled to the laser vibration measurement module, is used to detect the laser signal reflected by the measured target, and use the laser signal to perform confocal microscopic imaging to obtain image information of the measured target within the imaging object plane; A motion control displacement stage, used to carry a measured object and drive the measured object to move; The host computer is connected to the laser vibration measurement module, the microscopic optical imaging module, and the motion control displacement stage, and is used to control the laser vibration measurement module, the microscopic optical imaging module, and the motion control displacement stage to perform data analysis and processing on the vibration information of the measured target along the optical axis direction collected by the laser vibration measurement module and the image information of the measured target collected by the microscopic optical imaging module.

2. The laser confocal detection system according to claim 1, characterized in that: The laser vibration measurement module comprises: A heterodyne coherent optical path device, comprising: a laser and a heterodyne coherent module; the laser is used to generate detection light; the heterodyne coherent module comprises a measurement optical path and a reference optical path separated from each other, and is used to separate the detection light of the laser into a measurement light propagating along the measurement optical path and a reference light propagating along the reference optical path; a dual galvanometer device, arranged along the measuring optical path, for reflecting the measuring light to form a measuring light beam incident on the measured target and reflecting the echo light reflected from the measured target and transmitting it to the heterodyne coherent module, so that the heterodyne coherent module interferes the echo light with the reference light to form an electrical detection signal for coherent detection; and The signal restoration device is connected to the heterodyne coherent optical path device and the host computer, and is used to restore the vibration output by the heterodyne coherent optical path device and transmit it to the host computer, and the host computer measures the vibration data along the optical axis direction through a detection algorithm.

3. The laser confocal detection system according to claim 2, characterized in that: The heterodyne coherent module includes: a beam splitter, a polarization beam splitter, a laser shaping lens group, a beam combiner, and a photoelectric detector; The beam splitter is used to split the detection light of the laser into measurement light and reference light in a certain proportion; The polarization beam splitter is used to transmit the measurement light emitted by the beam splitter to the laser shaping mirror group and to reflect the echo light returned from the laser shaping mirror group; The laser shaping lens group is used to shape the measurement light emitted by the polarization beam splitter and to shape the returned echo light; The beam combiner is used to interfere the echo light reflected by the polarization beam splitter with the reference light emitted by the beam splitter to form an interference light signal for coherent detection; The photoelectric detector is used to perform photoelectric conversion on the interference light signal output by the light beam combiner to form an electrical detection signal with vibration information.

4. The laser confocal detection system according to claim 3, characterized in that: The laser shaping lens assembly comprises: a concave lens, disposed on the light-emitting side of the polarization beam splitter; and The convex lens is arranged on the light-emitting side of the concave lens, and the optical axis of the convex lens is coaxial with the optical axis of the concave lens.

5. The laser confocal detection system according to claim 3, characterized in that: The heterodyne coherent module further includes: a reflector and a frequency shifter arranged in the reference optical path; The reflector is used to reflect the reference light emitted by the beam splitter; The frequency shifter is used to perform frequency shift processing on the reference light reflected by the reflector.

6. The laser confocal detection system according to claim 2, characterized in that: The dual galvanometer device comprises: A first galvanometer is arranged along a first axis; A second galvanometer is arranged along a second axis; the first axis and the second axis form an imaging object plane perpendicular to the optical axis; and The galvanometer control module is used to control the first galvanometer to deflect along a first axis and / or control the second galvanometer to deflect along a second axis.

7. The laser confocal detection system according to claim 6, characterized in that: The galvanometer control module includes: a galvanometer rotation motor and a galvanometer controller, wherein the galvanometer rotation motor is connected to the first galvanometer and the second galvanometer, and the galvanometer controller is connected to the host computer and the galvanometer rotation motor, and is used to control the galvanometer rotation motor to drive one or both of the first galvanometer and the second galvanometer to deflect according to the instructions of the host computer; or, the galvanometer control module includes: a first galvanometer rotation motor, a second galvanometer rotation motor, and a galvanometer controller, wherein the first galvanometer rotation motor is connected to the first galvanometer, and the second galvanometer rotation motor is connected to the second galvanometer, and the galvanometer controller is connected to the host computer, the first galvanometer rotation motor, and the second galvanometer rotation motor, and is used to control the first galvanometer rotation motor to drive the first galvanometer to deflect and / or control the second galvanometer rotation motor to drive the second galvanometer to deflect according to the instructions of the host computer.

8. The laser confocal detection system according to claim 2, characterized in that: The signal restoration device comprises: A filtering module, used for filtering the electrical detection signal output by the heterodyne coherent optical path device; The signal restoration module is connected to the filtering module and is used to restore the electrical detection signal after filtering by the filtering module and transmit it to the host computer.

9. The laser confocal detection system according to claim 8, characterized in that: The signal restoration device further includes: an excitation module, which is used to generate an excitation signal and output the excitation signal to the measured target.

10. The laser confocal detection system according to claim 1, characterized in that: The microscopic optical imaging module includes: a single wavelength reflector, a stroboscopic light source, a microscopic objective lens group, an imaging focusing lens, and an imaging camera; The single-wavelength reflector is used to reflect the measurement light emitted by the laser vibration measurement module, reflect the echo light reflected by the measured target, and transmit the imaging light reflected by the measured target; A stroboscopic light source provides stroboscopic light; The microscope objective lens assembly is disposed between the single-wavelength reflector and the target to be measured, and is used to focus the measurement light emitted after being reflected by the single-wavelength reflector on the target to be measured; The imaging focusing lens is disposed between the single-wavelength reflector and the imaging camera, and is used to focus the imaging light emitted after being transmitted through the single-wavelength reflector onto the imaging camera; The imaging camera is connected to the host computer and is used to transmit images at different times to the host computer, and the host computer measures the in-plane vibration data through a detection algorithm.

11. The laser confocal detection system according to claim 10, characterized in that: The microscope optical imaging module also includes: a semi-transmitter and a semi-reflector, which is arranged between the single-wavelength reflector and the imaging focusing lens, and is used to reflect the stroboscopic light so that the stroboscopic light is transmitted through the single-wavelength reflector to the target to be measured, and transmit the imaging light reflected by the target to be measured so as to be transmitted to the imaging camera through the imaging focusing lens.

12. The laser confocal detection system according to claim 11, characterized in that: The single-wavelength reflector is a single-wavelength reflector, the semi-transparent reflector is a semi-transparent mirror, the single-wavelength reflector and the semi-transparent mirror are both incident at a 45° angle, the single-wavelength reflector is arranged along the first axis and the semi-transparent mirror is arranged along the second axis, or the single-wavelength reflector is arranged along the second axis and the semi-transparent mirror is arranged along the first axis.

13. The laser confocal detection system according to claim 1, characterized in that: The motion-controlled displacement stage is a three-dimensional displacement stage, which is controlled by the host computer to drive the target to be measured to move in the three-dimensional space formed by the first axis, the second axis, and the optical axis; or, the motion-controlled displacement stage is controlled by the host computer to drive the target to be measured to move in the imaging object plane formed by the first axis and the second axis and to drive the microscopic optical imaging module to move on the optical axis.

Images