Laser Interference Surface Shape Measurement Method, Medium, Device and System Based on Calibration Plate

Abstract

The present invention relates to the field of laser measurement technology, and in particular to a laser interference surface shape measurement method, medium, device and system based on a calibration plate. The method includes: attaching a reflecting mirror to a reference mirror to obtain the reflecting surface shape data of the reflecting mirror; tightly clamping a calibration glass plate between the reflecting mirror and the reference mirror to obtain the light-facing surface reflecting surface shape data and the mixed transmission surface shape data of the calibration glass plate; removing the reflecting mirror, moving the calibration glass plate along the laser optical axis to a preset measurement distance, and performing multi-surface synchronous measurement through a laser interferometer to respectively obtain the light-facing surface mixed reflection surface shape data and the measured surface shape mixed data; and then obtaining the target surface shape data of the measured surface. In the present invention, by introducing a movable calibration glass plate to establish a dual-reference measurement system, spatial calibration of the air flow disturbance error can be achieved. The structure of the present invention is simple, and the requirements for the measurement environment are relatively low. Only a single measurement is required to eliminate the interference of air turbulence and save measurement time.

Description

Background Art

[0002] As a device for realizing high-precision surface shape detection of optical elements, a laser interferometer has been widely used in ultra-precision machining fields such as aerospace, semiconductor processing, and optical processing. However, since its interference cavity is exposed to the external environment during the measurement process, its measurement results are extremely vulnerable to the interference of air flow. Currently, the commonly used methods to eliminate the influence of air disturbance are the vacuum chamber method or the forced turbulence method.

[0003] The vacuum chamber method means evacuating the air in the interference cavity to create a vacuum environment to avoid the interference caused by air flow.

[0004] The forced turbulence method is to achieve the forced flow of air through means such as a fan, making the air flow rapidly, avoiding the drift of a low-speed air mass between two mirrors, which may affect the measurement results, and using the method of averaging a large number of measurement times (23 times) to eliminate the random error caused by air flow disorder.

[0005] Among the above two methods, the vacuum chamber method has high environmental requirements, complex equipment, and high cost; while the forced turbulence method requires a large number of repeated measurements, which makes the entire measurement time longer and reduces the measurement efficiency. Summary of the Invention

[0006] For one of the above technical problems, the technical solution adopted in the present invention is as follows:

[0007] According to one aspect of the present invention, a laser interference surface shape measurement method based on a calibration plate is provided, and the method includes the following steps:

[0008] Attach a reflecting mirror to the reference mirror of the laser interferometer, and obtain the reflected surface shape data A of the reflecting mirror through the laser interferometer;

[0009] Clamp a calibration glass plate tightly between the reflecting mirror and the reference mirror, and obtain the light-facing surface reflected surface shape data B1 and the mixed transmission surface shape data C1 of the calibration glass plate through the laser interferometer; the calibration glass plate is an optical glass plate with light-facing surface reflection and double-sided transparency, and the light-facing surface of the calibration glass plate is arranged on the side close to the reference mirror;

[0010] Remove the reflecting mirror, move the calibration glass plate along the laser optical axis to a preset measurement distance, and arrange the side of the surface to be measured of the workpiece to be measured tightly against the backlight side of the calibration glass plate, and perform multi-surface synchronous measurement through the laser interferometer to respectively obtain the light-facing surface mixed reflected surface shape data B2 of the calibration glass plate and the surface shape mixed data C2 of the surface to be measured; the reference mirror, the calibration glass plate, the reflecting mirror, and the workpiece to be measured are all planar components;

[0011] According to A, B1, B2, C1, and C2, obtain the target surface shape data D of the surface to be measured; D satisfies the following conditions:

[0012] D = C2 - (B2 - B1) - (C1 - A).

[0013] Furthermore, the light transmittance of the calibration glass plate is 96%, and the reflectance of the light-facing surface of the calibration glass plate is 4%.

[0014] Furthermore, the calibration glass plate is quartz glass.

[0015] Furthermore, the specular reflectance of the mirror or the reflectance R of the surface to be measured B satisfies the following conditions:

[0016] ;

[0017] wherein, R A is the specular reflectance of the reference mirror.

[0018] Furthermore, the specular reflectances of both the reference mirror and the mirror are 4%.

[0019] Furthermore, when being closely arranged, the distance between adjacent surfaces of the two components is less than or equal to 10 mm.

[0020] According to the second aspect of the present invention, there is provided a laser interferometry surface shape measurement system based on a calibration plate for implementing the above-mentioned laser interferometry surface shape measurement method based on a calibration plate, including:

[0021] a laser interferometer, a reference mirror, a linear guide rail, a first clamping component, a second clamping component, a calibration glass plate and a mirror;

[0022] The reference mirror is fixedly arranged at the light outlet of the laser interferometer;

[0023] The linear guide rail is arranged parallel to the laser optical axis, and both the first clamping component and the second clamping component are slidably arranged on the linear guide rail; the first clamping component is located between the reference mirror and the second clamping component;

[0024] The calibration glass plate is clamped on the first clamping component, and the second clamping component is used for installing the mirror or the workpiece to be measured; the reference mirror, the calibration glass plate and the mirror are arranged parallel to each other.

[0025] Furthermore, the laser interferometer is an interferometer with multi-surface measurement capabilities.

[0026] According to the third aspect of the present invention, there is provided a non-transitory computer-readable storage medium storing a computer program, which when executed by a processor, implements the above-mentioned laser interferometry surface shape measurement method based on a calibration plate.

[0027] According to the fourth aspect of the present invention, there is provided an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the above-mentioned method for measuring the surface shape by laser interference based on a calibration plate is implemented.

[0028] The present invention has at least one of the following beneficial effects:

[0029] In the present invention, first, by closely arranging the reflecting mirror and the reference mirror, and closely arranging the reflecting mirror, the calibration glass plate and the reference mirror, the space between the reflecting mirror or the calibration glass plate and the reference mirror, and the space between the reflecting mirror and the calibration glass plate (that is, reducing the space of the interference cavity in the measurement) are minimized, which can greatly reduce the amount of air in the current interference cavity, and further greatly reduce the influence caused by air disturbance, so that the measured surface shape data A, B1, and C1 are all accurate surface shapes basically without air disturbance interference. And C1 is the data obtained by mixing and superimposing the transmitted wavefront of the calibration glass plate and the surface shape data of the reflecting mirror. Therefore, the transmitted wavefront of the calibration glass plate can be calibrated by C1 - A.

[0030] Then, by moving the calibration glass plate and the workpiece to be measured to the preset measurement position, the mixed reflected surface shape data B2 of the light-receiving surface of the calibration glass plate and the mixed data C2 of the surface to be measured are respectively obtained. At this time, since the calibration glass plate is far from the reference mirror, there is a large amount of air in the interference cavity, that is, the data of air disturbance are mixed in both B2 and C2. Since the previously obtained B1 is the reflected surface shape data of the light-receiving surface without air disturbance, the data of the current air disturbance can be calibrated by B2 - B1. Finally, by subtracting the transmitted wavefront of the calibration glass plate and the current air disturbance from C2, which is mixed with the current air disturbance error, the transmitted wavefront of the calibration glass plate, and the standard surface shape of the surface to be measured, the standard surface shape data of the surface to be measured, that is, the target surface shape data D, can be obtained.

[0031] In the present invention, by introducing a movable calibration glass plate to establish a dual-reference (one is the reference system composed of the reference mirror and the reflecting mirror, and the other is the reference system composed of the reference mirror, the calibration glass plate, and the reflecting mirror) measurement system, the spatial calibration of the airflow disturbance error can be realized.

[0032] Compared with the vacuum chamber method, it has a low cost, a simple structure, and relatively low requirements for the measurement environment. Compared with the forced turbulence method, after the calibration measurement of the calibration glass plate is completed, for the measurement of the surface shape of the workpiece to be measured, only a single measurement is required to eliminate the interference of air turbulence and obtain the surface shape of the measured mirror surface, saving a large amount of measurement time. Description of the Drawings

[0033] To more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0034] Figure 1 It is a flowchart of a laser interference surface shape measurement method based on a calibration plate provided by an embodiment of the present invention;

[0035] Figure 2 It is a schematic diagram of the operation layout of S100 provided by an embodiment of the present invention;

[0036] Figure 3 It is a schematic diagram of the operation layout of S200 provided by an embodiment of the present invention;

[0037] Figure 4 It is a schematic diagram of the operation layout of S300 provided by an embodiment of the present invention;

[0038] Figure 5 It is a surface shape data diagram when the test piece is a plane mirror provided by an embodiment of the present invention;

[0039] Figure 6 It is a schematic diagram of the overall structure of a laser interference surface shape measurement system based on a calibration plate provided by an embodiment of the present invention;

[0040] Figure 7 It is a schematic diagram of the side view structure of a laser interference surface shape measurement system based on a calibration plate provided by an embodiment of the present invention.

[0041] 1 Laser interferometer, 2 Reference mirror, 3 Calibration glass plate, 4 Reflecting mirror, 5 Linear guide, 6 Second clamping assembly, 7 First clamping assembly, 8 Test piece. Detailed implementation manners

[0042] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0043] As a possible embodiment of the present invention, as Figures 1 to 4 , a laser interference surface shape measurement method based on a calibration plate is provided, and the method includes the following steps:

[0044] S100: Attach the mirror 4 to the reference mirror 2 of the laser interferometer 1, and obtain the reflected surface shape data A of the mirror 4 through the laser interferometer 1.

[0045] As Figure 2 As shown in the layout of the measurement optical path, the mirror 4 is as close as possible to the surface of the reference mirror 2 to minimize the space between the mirror 4 and the reference mirror 2, that is, to reduce the space of the interference cavity in the measurement, which can greatly reduce the amount of air in the current interference cavity, and then greatly reduce the influence brought by air disturbance and avoid environmental interference. The measured surface shape data A is basically an accurate surface shape without air disturbance interference.

[0046] Since in the actual use process, whether it is the reference mirror 2 or the mirror 4, corresponding mechanical frames are provided on the outer circumference of them, and even fixtures are connected externally during use, so when the reference mirror 2 and the mirror 4 are closely arranged, it is often difficult to achieve the effect that the adjacent mirror surfaces of the two are completely attached together. Therefore, the close arrangement described in this embodiment specifically means that the distance between adjacent surfaces of the two components is less than or equal to 10 mm. Thus, when selecting the reference mirror 2 and the mirror 4, those with narrow mechanical frames can be selected as much as possible to reduce the distance between the adjacent mirror surfaces of the two.

[0047] In addition, the laser interferometer 1 in this embodiment is a laser interferometer 1 with multi-surface measurement capabilities. This type of laser interferometer 1 can synchronously measure multi-surface interference cavities for multi-surface interference and surface shape measurement of complex interference cavities. For example, an MST (Multiple Surface Technology) laser interferometer can be used.

[0048] Specifically, in S100, the parallel beam emitted by the MST laser interferometer irradiates on the mirror 4, and then after being reflected by the mirror 4, it returns to the MST laser interferometer and forms corresponding interference data with the light reflected by the reference mirror 2 to obtain the cavity surface shape, that is, the reflected surface shape data A of the mirror 4.

[0049] S200: Clamp the calibration glass plate 3 tightly between the mirror 4 and the reference mirror 2, and obtain the light-facing surface reflected surface shape data B1 and the mixed transmission surface shape data C1 of the calibration glass plate 3 through the laser interferometer 1. The calibration glass plate 3 is an optical glass plate with light-facing surface reflection and double-sided transmissivity, and the light-facing surface of the calibration glass plate 3 is arranged on the side close to the reference mirror 2. The calibration glass plate 3 can be quartz glass.

[0050] As Figure 3As shown in the arrangement of the measurement optical path, a calibration glass plate 3 is inserted between the reflector 4 and the reference mirror 2. After the calibration glass plate 3 is inserted, the reflector 4, the calibration glass plate 3 and the reference mirror 2 still need to be kept in close contact, so that the air in the interference cavity can be excluded as much as possible to avoid the influence of air disturbance, so that the measured surface data B1 and C1 are basically accurate surface data without interference from air disturbance.

[0051] Specifically, in S200, the MST laser interferometer emits a parallel light beam through the reference mirror 2, passes through the calibration glass plate 3, and illuminates the reflector 4. Then, it is reflected by the reflector 4 and passes through the glass calibration glass plate 3 again, and then returns to the MST laser interferometer to form corresponding interference data with the light reflected by the reference mirror 2, and obtains a mixed transmission surface shape, that is, data C1 after the transmission wavefront of the calibration glass plate 3 and the surface shape data of the reflector 4 are mixed and superimposed.

[0052] According to S100 and S200, C1 is the data obtained by mixing and superimposing the transmission wavefront of the calibration glass plate 3 and the surface shape data of the reflector 4, and A is the reflection surface shape data of the reflector 4, so the transmission wavefront of the calibration glass plate 3 can be calibrated by C1-A.

[0053] At the same time, the parallel light beam emitted by the MST laser interferometer through the reference mirror 2 is reflected by the light-facing surface of the calibration glass plate 3 and then returns to the MST laser interferometer to form corresponding interference data with the light reflected by the reference mirror 2 to obtain the surface shape data B1 of the light-facing surface of the calibration glass plate 3.

[0054] S300: Remove the reflector 4, move the calibration glass plate 3 along the laser optical axis to the preset measurement distance, place the test surface of the object to be measured 8 close to the backlight side of the calibration glass plate 3, perform multi-surface synchronous measurement through the laser interferometer 1, and obtain the mixed reflection surface shape data B2 of the light-facing surface of the calibration glass plate 3 and the mixed surface shape data C2 of the test surface. The reference mirror 2, the calibration glass plate 3, the reflector 4 and the object to be measured 8 are all planar components.

[0055] like Figure 4 As shown in the measurement optical path arrangement, the interference cavity is pulled back to the normal distance (that is, the preset measurement distance) at this time. This distance is set for the convenience of human-machine operation during the measurement process. As the distance of the interference cavity increases, a large amount of air exists in the interference cavity, and the corresponding air disturbance is bound to exist in the measured surface data in this state, that is, data with air disturbance are mixed in B2 and C2.

[0056] In S300, the multi-surface measurement mode of the MST laser interferometer is used, and the mirror 4 is replaced with the mirror to be measured (i.e., the workpiece 8 to be measured), and the calibration glass plate 3 is still kept in close contact with the mirror to be measured. The parallel light beam emitted by the reference mirror 2 of the MST laser interferometer first passes through the calibration glass plate 3, irradiates on the mirror to be measured and then is reflected, and then passes through the calibration glass plate 3 again and returns to the MST laser interferometer, forming corresponding interference data with the light reflected by the reference mirror 2, obtaining the data mixed with the current air disturbance error, the transmission wavefront of the calibration glass plate 3 and the standard surface shape of the surface to be measured, that is, the mixed surface shape data C2 of the surface to be measured.

[0057] At the same time, the parallel light beam emitted by the reference mirror 2 of the MST laser interferometer is reflected on the light-facing surface of the calibration glass plate 3 and returns to the MST laser interferometer, forming corresponding interference data with the light reflected by the reference mirror 2, obtaining the mixed reflection surface shape of the light-facing surface of the calibration glass plate 3 with air interference, that is, B2.

[0058] Since B1 obtained in the previous S200 is the data of the light-facing surface reflection surface shape without air disturbance, the current air disturbance data can be calibrated by B2 - B1.

[0059] S400: According to A, B1, B2, C1 and C2, obtain the target surface shape data D of the surface to be measured. D satisfies the following conditions:

[0060] D = C2 - (B2 - B1) - (C1 - A).

[0061] After obtaining the transmission wavefront C1 - A of the calibration glass plate 3 and the current air disturbance B2 - B1 according to the steps of S100 to S300, the transmission wavefront of the calibration glass plate 3 and the current air disturbance mixed in C2 can be removed, and then the standard surface shape of the surface to be measured, that is, the target surface shape data D, can be obtained. This embodiment can be used in the field of surface shape measurement and evaluation of plane mirrors, such as evaluating the flatness of the surface shape. As Figure 5 shown, it is the target surface shape data D of the plane mirror obtained by using the method in this embodiment. Among them, RMS, PV, and PVr are commonly used parameters for characterizing the surface shape quality of optical elements. RMS (root mean square): This value is a statistical description of the error distribution of the entire optical surface, and is obtained by calculating the square root of the average value of the squares of the errors of all measurement points. The RMS value can better reflect the overall quality of the optical surface, especially suitable for evaluating the influence of random errors. PV (peak-to-valley value): It represents the maximum difference between the highest point and the lowest point on the optical surface. This parameter intuitively reflects the maximum possible range of surface errors. PVr = PV 36Zernike + 3σ 36Zernike Residual . Among them, PV 36Zernike is the PV value after the wavefront is fitted by the Zernike polynomial, and 3σ36Zernike Residual is three times the root mean square value of the residual wavefront between the original wavefront and the fitted wavefront, which respectively describe the low-frequency and high-frequency parts of the wavefront. Using this evaluation parameter can remove the influence of burrs and dirt points on the wavefront in a high-resolution interferometer, can better ensure the repeatability of the measurement, and can more completely reflect the full-band information of the wavefront during the result comparison process.

[0062] As another possible embodiment of the present invention, a laser interferometry surface shape measurement system based on a calibration plate is provided for implementing the above-mentioned laser interferometry surface shape measurement method based on a calibration plate, as Figure 6 and Figure 7 shown. The system includes:

[0063] a laser interferometer 1, a reference mirror 2, a linear guide 5, a first clamping assembly 7, a second clamping assembly 6, a calibration glass plate 3, and a reflector 4.

[0064] The reference mirror 2 is fixedly arranged at the light exit of the laser interferometer 1.

[0065] The linear guide 5 is arranged parallel to the laser optical axis. The first clamping assembly 7 and the second clamping assembly 6 are both slidably arranged on the linear guide 5. The first clamping assembly 7 is located between the reference mirror 2 and the second clamping assembly 6. That is, the linear guide 5 is successively provided with a calibration glass plate clamping device (that is, the first clamping assembly 7) and a reflector clamping device (that is, the second clamping assembly 6) from one side of the MST laser interferometer lens along the extending direction of the optical axis. The calibration glass plate clamping device and the reflector clamping device adopt a split design and support independent or synchronous movement.

[0066] The calibration glass plate 3 is clamped on the first clamping assembly 7. The second clamping assembly 6 is used to install the reflector 4 or the workpiece under test 8. The reference mirror 2, the calibration glass plate 3, and the reflector 4 are arranged parallel to each other. In this embodiment, the reference mirror 2, the calibration glass plate 3, and the reflector 4 are installed in a common optical path, that is, the optical axis of the laser just passes through the centers of the reference mirror 2, the calibration glass plate 3, and the reflector 4.

[0067] In this embodiment, through the first clamping assembly 7 and the second clamping assembly 6, the sliding arrangement on the linear guide 5 can facilitate the independent adjustment of the positions of the calibration glass plate 3 and the reflector 4 or the workpiece under test 8 in the optical axis direction to meet the requirements in S100 to S300.

[0068] As another possible embodiment of the present invention, the specular reflectivity of the reflector 4 or the reflectivity R of the surface under test B satisfies the following conditions:

[0069] ;

[0070] wherein, RA is the specular reflectivity of the reference mirror 2.

[0071] In this embodiment, in order to ensure that a clear and distinct interference phenomenon that is convenient for the device to detect and analyze appears on the laser interferometer, it is also necessary to make the specular reflectivity of the reference mirror 2 and the reflectivity of the surface to be measured (such as the specular surface of the mirror 4 or the surface to be measured of the workpiece 8) satisfy the relationship constrained by the above formula.

[0072] The degree to which the fringes generated by light wave interference can be observed. Usually, it can be represented by the visibility V, and V satisfies the following conditions: ;

[0073] where:

[0074] I max is the maximum light intensity in the interference pattern, usually corresponding to the light intensity generated by constructive interference (when the phases of the two light waves are the same).

[0075] I min is the minimum light intensity in the interference pattern, usually corresponding to the light intensity generated by destructive interference (when the phases of the two light waves are opposite).

[0076] V reflects the contrast of the interference fringes, that is, the light intensity difference between the bright fringes and the dark fringes. The value range of V is from 0 to 1. When the difference between I min and I max is larger, it means that the light intensity contrast generated by constructive interference and destructive interference is very high, the visibility V is higher, and the interference fringes are clearer. That is, a higher value indicates that the interference fringes are more obvious and easier to identify. In this embodiment, usually when V > 0.2, qualified interference fringes can appear.

[0077] In addition, when two light waves with light intensities I1 and I2 interfere, the interference light intensity I(x, y) at a certain point (x, y) is: ;

[0078] where, and are the phases corresponding to the two light waves of I1 and I2 respectively. Therefore, from the above formula, it can be obtained that , ; so .

[0079] At the same time, since the two light waves interfering with each other in this embodiment are both obtained by reflection from the surfaces of different devices. Therefore, the light intensity of the light waves in this embodiment is proportional to the reflectivity of the corresponding reflecting surface. Corresponding from , it can be obtained that . Thus, according to this relational expression, the reference mirror 2 and the mirror 4 or the reference mirror 2 and the workpiece 8 can be better adapted and selected.

[0080] Specifically, in this embodiment, the specular reflectance of the reference mirror 2 and the reflecting mirror 4 can both be 4%. The light transmittance of the calibration glass plate 3 is 96%, and the reflectance of the light-facing surface of the calibration glass plate 3 is 4%. Since the light transmittance of the calibration glass plate 3 is relatively high, the reduction effect on the transmitted light wave is extremely small and can be ignored in this embodiment.

[0081] In addition, although the steps of the methods in this disclosure are described in a specific order in the drawings, this does not require or imply that these steps must be performed in that specific order, or that all of the illustrated steps must be performed to achieve the desired result. Additionally or alternatively, some steps may be omitted, multiple steps may be combined into one step for execution, and / or one step may be decomposed into multiple steps for execution, etc.

[0082] Through the description of the above embodiments, those skilled in the art can easily understand that the example embodiments described herein can be implemented by software, or by a combination of software and necessary hardware. Therefore, the technical solutions according to the embodiments of this disclosure can be embodied in the form of a software product, which can be stored in a non-volatile storage medium (such as a CD-ROM, USB flash drive, mobile hard disk, etc.) or on a network, including several instructions to enable a computing device (such as a personal computer, server, mobile terminal, or network device, etc.) to execute the methods according to the embodiments of this disclosure.

[0083] In an exemplary embodiment of this disclosure, an electronic device capable of implementing the above method is also provided.

[0084] Those skilled in the art can understand that various aspects of the present invention can be implemented as a system, method, or program product. Therefore, various aspects of the present invention can be specifically implemented in the following forms, namely: a complete hardware implementation, a complete software implementation (including firmware, microcode, etc.), or an implementation combining hardware and software aspects, which can be collectively referred to herein as "circuitry", "module", or "system".

[0085] The electronic device according to this embodiment of the present invention. The electronic device is merely an example and should not impose any limitations on the functions and usage scope of the embodiments of the present invention.

[0086] The electronic device is presented in the form of a general-purpose computing device. The components of the electronic device may include, but are not limited to: at least one of the above-mentioned processors, at least one of the above-mentioned memories, and a bus connecting different system components (including the memory and the processor).

[0087] Among them, the memory stores program code that can be executed by the processor, enabling the processor to execute the steps according to various exemplary embodiments of the present invention described in the "Exemplary Method" section above in this specification.

[0088] The memory may include a readable medium in the form of volatile memory, such as random access memory (RAM) and / or cache memory, and may further include read-only memory (ROM).

[0089] The memory may also include a program / utility having a set (at least one) of program modules. Such program modules include, but are not limited to: an operating system, one or more application programs, other program modules, and program data. Each or some combination of these examples may include an implementation of a network environment.

[0090] The bus may represent one or more of several types of bus structures, including a memory bus or memory controller, a peripheral bus, a graphics acceleration port, a processor, or a local bus using any of the various bus structures.

[0091] The electronic device may also communicate with one or more external devices (such as a keyboard, a pointing device, a Bluetooth device, etc.), may also communicate with one or more devices that enable a user to interact with the electronic device, and / or may communicate with any device that enables the electronic device to communicate with one or more other computing devices (such as a router, a modem, etc.). Such communication may be carried out through an input / output (I / O) interface. Moreover, the electronic device may also communicate with one or more networks (such as a local area network (LAN), a wide area network (WAN), and / or a public network, such as the Internet) through a network adapter. The network adapter communicates with other modules of the electronic device through the bus. It should be understood that although not shown in the figure, other hardware and / or software modules may be used in conjunction with the electronic device, including but not limited to: microcode, device drivers, redundant processors, external disk drive arrays, RAID systems, tape drives, and data backup storage systems, etc.

[0092] Through the description of the above embodiments, those skilled in the art can easily understand that the exemplary embodiments described herein can be implemented by software, or can be implemented by a combination of software and necessary hardware. Therefore, the technical solution according to the embodiments of the present disclosure can be embodied in the form of a software product, which can be stored in a non-volatile storage medium (which can be a CD-ROM, a USB flash drive, a mobile hard disk, etc.) or on a network, including several instructions to enable a computing device (which can be a personal computer, a server, a terminal device, or a network device, etc.) to execute the method according to the embodiments of the present disclosure.

[0093] In an exemplary embodiment of the present disclosure, there is also provided a computer-readable storage medium, on which a program product capable of implementing the above-described method of this specification is stored. In some possible implementation manners, various aspects of the present invention can also be implemented in the form of a program product, which includes program code. When the program product runs on a terminal device, the program code is used to cause the terminal device to execute the steps according to various exemplary embodiments of the present invention described in the above "Exemplary Method" section of this specification.

[0094] The program product may employ any combination of one or more readable media. The readable media may be a readable signal medium or a readable storage medium. The readable storage medium may be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination of the above. More specific examples (a non-exhaustive list) of the readable storage medium include: an electrical connection having one or more wires, a portable disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above.

[0095] The computer-readable signal medium may include a data signal propagated in a baseband or as a part of a carrier wave, in which the readable program code is carried. Such a propagated data signal may take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination of the above. The readable signal medium may also be any readable medium other than the readable storage medium, which can send, propagate, or transmit a program for use by or in connection with an instruction execution system, apparatus, or device.

[0096] The program code contained on the readable medium may be transmitted by any appropriate medium, including but not limited to wireless, wired, optical fiber, RF, etc., or any suitable combination of the above.

[0097] The program code for performing the operations of the present invention can be written in any combination of one or more programming languages, including object-oriented programming languages such as Java, C++, etc., and also including conventional procedural programming languages such as the "C" language or similar programming languages. The program code can be executed entirely on the user's computing device, partially on the user's device, executed as a stand-alone software package, partially on the user's computing device and partially on a remote computing device, or entirely on a remote computing device or server. In the case of a remote computing device, the remote computing device can be connected to the user's computing device through any type of network, including a local area network (LAN) or a wide area network (WAN), or, alternatively, can be connected to an external computing device (e.g., by using an Internet service provider to connect through the Internet).

[0098] In addition, the above-mentioned drawings are only schematic illustrations of the processes included in the method according to the exemplary embodiments of the present invention, rather than for limiting purposes. It is easy to understand that the processes shown in the above-mentioned drawings do not indicate or limit the chronological order of these processes. Additionally, it is also easy to understand that these processes can be executed synchronously or asynchronously in, for example, multiple modules.

[0099] It should be noted that although several modules or units of the device for action execution are mentioned in the above detailed description, this division is not mandatory. In fact, according to the embodiments of the present disclosure, the features and functions of two or more of the above-mentioned modules or units can be embodied in one module or unit. Conversely, the features and functions of one module or unit described above can be further divided and embodied by multiple modules or units.

[0100] The above are only the specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention should be covered by the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.

Claims

1. A laser interference surface shape measurement method based on a calibration plate, characterized in that, The method includes the following steps: Attach a reflecting mirror to the reference mirror of the laser interferometer, and obtain the reflected surface shape data A of the reflecting mirror through the laser interferometer; Clamp a calibration glass plate tightly between the reflecting mirror and the reference mirror, and obtain the incident surface reflected surface shape data B1 and the mixed transmission surface shape data C1 of the calibration glass plate through the laser interferometer; the calibration glass plate is an optical glass plate with incident surface reflection and double-sided transmissivity, and the incident surface of the calibration glass plate is arranged on the side close to the reference mirror; Remove the reflecting mirror, move the calibration glass plate along the laser optical axis to a preset measurement distance, and arrange the side of the surface to be measured of the test piece closely against the backlight side of the calibration glass plate, and perform multi-surface synchronous measurement through the laser interferometer to respectively obtain the incident surface mixed reflection surface shape data B2 of the calibration glass plate and the surface shape mixed data C2 of the surface to be measured; the reference mirror, the calibration glass plate, the reflecting mirror and the test piece are all planar components; According to A, B1, B2, C1 and C2, obtain the target surface shape data D of the surface to be measured; D satisfies the following conditions: D = C2 - (B2 - B1) - (C1 - A).

2. The method according to claim 1, wherein The light transmittance of the calibration glass plate is 96%, and the reflectance of the incident surface of the calibration glass plate is 4%.

3. The method according to claim 2, wherein The calibration glass plate is a quartz glass.

4. The method according to claim 2, wherein The specular reflectance of the mirror or the reflectance R of the surface to be measured B satisfies the following conditions: ； Among them, R A is the specular reflectance of the reference mirror.

5. The method according to claim 1, characterized in that The specular reflectivities of the reference mirror and the reflecting mirror are both 4%.

6. The method according to claim 1, wherein When closely arranged, the distance between adjacent surfaces of the two components is less than or equal to 10 mm.

7. A laser interferometry surface shape measurement system based on a calibration plate, which is used to implement the laser interferometry surface shape measurement method based on a calibration plate according to any one of the above-mentioned claims 1-6, and is characterized in that, Including: A laser interferometer, a reference mirror, a linear guide, a first clamping component, a second clamping component, a calibration glass plate and a reflecting mirror; The reference mirror is fixedly arranged at the light outlet of the laser interferometer; The linear guide is arranged parallel to the laser optical axis, and both the first clamping component and the second clamping component are slidably arranged on the linear guide; the first clamping component is located between the reference mirror and the second clamping component; The calibration glass plate is clamped on the first clamping component, and the second clamping component is used to mount the reflecting mirror or the test piece; the reference mirror, the calibration glass plate and the reflecting mirror are arranged parallel to each other; 8. A laser interferometry surface shape measurement system based on a calibration plate according to claim 7, characterized in that, The laser interferometer is an interferometer with multi-surface measurement ability.

9. A non-transitory computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by a processor, it implements a laser interferometry surface shape measurement method based on a calibration plate according to any one of claims 1 to 6.

10. An electronic 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, it implements a laser interferometry surface shape measurement method based on a calibration plate according to any one of claims 1 to 6.

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