Large-aperture reflector contour detection method

Abstract

The invention relates to the technical field of reflector contour detection, and particularly provides a large-aperture reflector contour detection method, which is characterized in that a one-dimensional or two-dimensional scanning sensor is arranged in a non-contact point displacement sensor array to form a contour detection device, and a line laser scanning sensor is promoted to traverse a reflector; the one-dimensional or two-dimensional scanning sensor and the non-contact point displacement sensor array periodically collect the distance of the reflector in the traversing process, and distance data of high-density sampling points on the reflector are obtained through the one-dimensional or two-dimensional scanning sensor; distance data of low-density sampling points on the reflector are obtained through a non-contact point displacement sensor array, after the low-density sampling points are corrected, the distance data of high-density sampling points and the low-density contour surface shape are fitted, and the high-density contour surface shape of the reflector is generated. The advantages of a non-contact point displacement sensor and a laser scanning sensor are combined, and the data point density is improved while the detection precision is ensured.

Description

Technical Field

[0001] The present invention belongs to the technical field of reflector profile detection, and particularly relates to a method for detecting the profile of a large-aperture reflector. Background Art

[0002] Large-aperture reflectors play a crucial role in many fields. For example, in the field of astronomy, large astronomical telescopes require large-aperture reflectors to collect more light to observe distant galaxies and celestial bodies, thus promoting human exploration and understanding of the universe; in the field of laser technology, large-aperture reflectors are used in high-power laser systems, which can effectively guide and focus laser beams to achieve applications such as laser processing and laser communication. In addition, in fields such as aerospace, large-aperture reflectors are also one of the key components, playing an indispensable role in improving the performance and function of the system.

[0003] In optical processing, the detection accuracy and efficiency of the reflector profile detection process directly affect the quality and efficiency of optical processing. Traditional reflector profile detection methods mostly use contact measurements, such as coordinate measuring machines. Although these methods can obtain high measurement accuracy, there are many problems when measuring large-aperture reflectors. For example, contact measurement may cause scratches or damage to the reflector surface, affecting its optical performance; and the measurement process is relatively complex, with low efficiency, making it difficult to meet the dual requirements of detection efficiency and accuracy in modern optical processing. In addition, for some reflectors with special shapes, there may be inaccessible areas in contact measurement, resulting in incomplete measurement.

[0004] In addition, some other detection methods have also been proposed currently, as follows: For example, a Chinese invention patent with publication number CN116295108A, publication date of June 23, 2023, and title of "A Matrix Profile Measurement Method and Device" uses a matrix arrangement of multiple high-precision displacement sensors to achieve the profile measurement of a reflector. Since each data point corresponds to a high-precision displacement sensor, a large number of high-precision displacement sensors are required, resulting in high costs. And due to the constraints of installation space and principle, the interval between data points is more than 10 mm, and high-density profile data acquisition cannot be achieved.

[0005] For example, a Chinese invention patent with publication number CN115164773A, publication date of October 11, 2022, and title of "A Profile Detection Method and Device for a Large-Aperture Flat Mirror" uses 3 probes to achieve the profile detection of a flat mirror. At the same time, only the height values of 3 points can be collected, and the data acquisition efficiency is limited. At the same time, there are large cumulative errors, and the profile measurement accuracy is limited.

[0006] In summary, the existing large-aperture mirror profile detection technologies have problems such as limited detection accuracy, low detection efficiency, high cost, and low data point density. Therefore, there is an urgent need to design a large-aperture mirror profile detection device and method that can effectively overcome the above problems. Summary of the Invention

[0007] In view of this, the present invention aims to provide a large-aperture mirror profile detection method, which combines a non-contact point displacement sensor array and a one-dimensional or two-dimensional scanning sensor to detect the profile of a large-aperture mirror. The non-contact point displacement sensor has higher measurement accuracy but lower sampling point density. High-density sampling point data is obtained through sampling by the one-dimensional or two-dimensional scanning sensor, and the high-density sampling point data and the low-density sampling point data are fused. The one-dimensional or two-dimensional scanning sensor increases the data point density and realizes high-precision and high-data-density profile measurement.

[0008] To achieve the above object, the technical solution of the present invention is realized as follows: The present invention provides a large-aperture mirror profile detection method, including: Constructing a non-contact point displacement sensor array, which includes a plurality of equally spaced non-contact point displacement sensors arranged in the same plane, replacing at least one non-contact point displacement sensor in the non-contact point displacement sensor array with a one-dimensional or two-dimensional scanning sensor, or arranging one of the one-dimensional or two-dimensional scanning sensors between any two non-contact point displacement sensors in the non-contact point displacement sensor array; Making the line laser scanning sensor traverse the mirror. During the traversing process, the one-dimensional or two-dimensional scanning sensor and the non-contact point displacement sensor array periodically collect the distances of the mirror. The sampling points of the non-contact point displacement sensor array partially overlap in two adjacent samplings; obtaining the distance data of the high-density sampling points on the mirror through the one-dimensional or two-dimensional scanning sensor; obtaining the distance data of the low-density sampling points on the mirror through the non-contact point displacement sensor array, and the distance data of each low-density sampling point includes the distance data collected by multiple different non-contact point displacement sensors; Based on the principle that the distances collected by different non-contact point displacement sensors for the same low-density sampling point are equal, correcting the distance data of the low-density sampling points, and fitting the corrected distance data of all low-density sampling points to obtain the high-precision low-density profile surface of the mirror; Fusing the high-density sampling point distance data obtained by the one-dimensional or two-dimensional scanning sensor and the high-precision low-density profile surface to generate the high-precision high-density profile surface of the mirror.

[0009] Preferably, the one-dimensional or two-dimensional scanning sensor is a line laser scanning sensor or a surface displacement sensor.

[0010] Preferably, the length of the single-cycle detection range of the one-dimensional or two-dimensional scanning sensor is an integer multiple of the distance between adjacent non-contact point displacement sensors.

[0011] Preferably, before the line laser scanning sensor traverses the mirror, it further includes: calibrating the one-dimensional or two-dimensional scanning sensor and the non-contact point displacement sensor using a standard plane or a standard sphere.

[0012] Preferably, preset the relative movement path between the non-contact point displacement sensor array, the one-dimensional or two-dimensional scanning sensor, and the mirror; Drive the non-contact point displacement sensor array and the one-dimensional or two-dimensional scanning sensor to move according to the relative movement path; Or, control the mirror to move according to the relative movement path.

[0013] Preferably, the traversing method of the line laser scanning sensor traversing the mirror is the polar coordinate rotation method or the XY-axis grating traversing method.

[0014] Preferably, the sampling times of the one-dimensional or two-dimensional scanning sensor and the non-contact point displacement sensor array are the same.

[0015] Preferably, based on the principle that the distances collected by different non-contact point displacement sensors at the same low-density sampling point are equal, correct the distance data of the low-density sampling points, including: For any (n + 1)-th sampling period, the low-density sampling points of the non-contact point displacement sensor array partially overlap with the low-density sampling points of the n-th sampling period. Align the distance data of the overlapping low-density sampling points, and supplement the distance data of the non-overlapping low-density sampling points to the aligned distance data, and iteratively correct the distance data of the low-density sampling points of all sampling periods in this way.

[0016] Preferably, the alignment method is: using the distance data of the low-density sampling points of the n-th sampling period as a standard, compensate and correct the distance data of all low-density sampling points of the (n + 1)-th sampling period to make the distance data of the overlapping low-density sampling points equal.

[0017] Preferably, it further includes: calibrating the relative movement error between the non-contact point displacement sensor array, the one-dimensional or two-dimensional scanning sensor, and the mirror during the process of the line laser scanning sensor traversing the mirror, and compensating the movement error for the distance data of the high-density sampling points and the low-density sampling points.

[0018] Compared with the prior art, the present invention can achieve the following beneficial effects: Compared with the traditional three - coordinate contour detection scheme, the present invention combines a non - contact point displacement sensor array and a laser scanning sensor. By using the non - contact point displacement sensor array, the contour detection accuracy is ensured, and the laser scanning sensor is used to increase the data point density, solving the drawback of low data point density caused by limited space. Moreover, this combination method effectively improves the measurement efficiency, achieving high - precision and high - data - density contour measurement of large - aperture reflectors.

[0019] The present invention controls different non - contact point displacement sensors in the non - contact point displacement sensor array to perform multiple measurements on the same sampling point, and takes the principle that the sampling data of the same sampling point in different sampling periods is equal. Through an iterative method, data correction and alignment are carried out, effectively reducing the influence of motion device errors on the sampling results, reducing the requirements for the motion accuracy of the non - contact point displacement sensor array and the laser scanning sensor on the motion device, and it can be directly integrated into devices such as numerical control machine tools or robotic arms, improving the convenience of reflector contour detection. Brief Description of the Drawings

[0020] The drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The schematic embodiments and descriptions thereof of the present invention are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings: Figure 1 is a schematic diagram of the measuring device provided according to an embodiment of the present invention; Figure 2 is a schematic diagram of calibrating the measuring device with a standard part provided according to an embodiment of the present invention; Figure 3 is a schematic diagram of performing contour detection on a reflector provided according to an embodiment of the present invention; Figure 4 is a schematic diagram of the motion path of scanning the reflector in a polar - coordinate rotation manner provided according to an embodiment of the present invention; Figure 5 is a schematic diagram of the motion path of scanning the reflector in an XY - axis grating traversal manner provided according to an embodiment of the present invention; Figure 6 is a schematic diagram of the periodic acquisition of low - density sampling points and high - density sampling points provided according to an embodiment of the present invention.

[0021] Among them, the reference numerals include: Non - contact point displacement sensor 1, one - dimensional or two - dimensional scanning sensor 2, standard part 3, reflector 4. Detailed Embodiments

[0022] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and do not constitute a limitation to the present invention. Similar elements in different embodiments are denoted by related similar element numbers. In the following embodiments, many details are described to enable a better understanding of the present invention. However, those skilled in the art can easily recognize that some of the features can be omitted in different situations, or can be replaced by other elements, materials and methods. In some cases, some operations related to the present invention are not shown or described in the specification, which is to avoid the core part of the present invention being overwhelmed by excessive description. For those skilled in the art, it is not necessary to describe these related operations in detail, and they can fully understand the related operations based on the description in the specification and the general technical knowledge in the art.

[0023] It should be noted that, without conflict, the embodiments and features in the embodiments of the present invention can be combined with each other to form various implementation manners. At the same time, the steps or actions in the method description can also be adjusted in the order that is obvious to those skilled in the art. Therefore, the various sequences in the specification and drawings are only for clearly describing a certain embodiment and do not mean that they are the necessary sequences, unless it is stated that a certain sequence must be followed.

[0024] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present invention. In addition, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, the features defined with "first", "second", etc. can explicitly or implicitly include one or more of such features. In the description of the present invention, unless otherwise specified, the meaning of "a plurality of" is two or more.

[0025] In the description of the present invention, it should be noted that unless otherwise clearly defined and limited, the terms "installation", "connection", and "coupling" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood through specific situations.

[0026] The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments.

[0027] In an embodiment of the present invention, a method for detecting the profile of a large-aperture mirror is provided. By combining a non-contact point displacement sensor array and a laser scanning sensor, the characteristics of high sampling accuracy of the non-contact point displacement sensor array and high sampling density of the laser scanning sensor are integrated, realizing high-precision and high-data-density profile detection of the large-aperture mirror, and solving the problem that the data density of traditional profile detection methods is affected by space limitations. Specifically, the process of detecting the profile of the large-aperture mirror is as follows: S1: As Figure 1 shown, a non-contact point displacement sensor array is constructed. The non-contact point displacement sensor array includes M×N non-contact point displacement sensors 1. Usually, the sensor array form of N×N is preferably selected. All the non-contact point displacement sensors 1 in the non-contact point displacement sensor array are in the same plane, and the distances between adjacent non-contact point displacement sensors 1 are equal. Then, at least one non-contact point displacement sensor 1 in the non-contact point displacement sensor array is replaced with a one-dimensional or two-dimensional scanning sensor 2. Usually, one non-contact point displacement sensor 1 at the center position of the non-contact point displacement sensor array is replaced with a one-dimensional or two-dimensional scanning sensor 2. The one-dimensional or two-dimensional scanning sensor 2 can specifically select a one-dimensional line laser scanning sensor or a two-dimensional surface displacement sensor. The line laser scanning sensor can simultaneously realize multi-point detection in a linear shape, and the surface displacement sensor. And can simultaneously realize multi-point effective detection in the positive direction area. When a line laser scanning sensor is selected, the single-cycle detection length of the line laser scanning sensor is an integer multiple of the distance between adjacent non-contact point displacement sensors 1, preferably the single-cycle detection length is equal to the distance between adjacent non-contact point displacement sensors 1; when a surface displacement sensor is selected, the effective detection range of the surface displacement sensor is set as a square, and the side length of the single-cycle effective detection range of the surface displacement sensor is an integer multiple of the distance between adjacent non-contact point displacement sensors 1, preferably the side length of the single-cycle effective detection range is equal to the distance between adjacent non-contact point displacement sensors 1.

[0028] In addition, a one-dimensional or two-dimensional scanning sensor 2 can also be inserted into the gap between any two non-contact point displacement sensors 1 in the non-contact point displacement sensor array.

[0029] After all the non-contact point displacement sensors 1 and the one-dimensional or two-dimensional scanning sensor 2 are selected and designed, they can be fixed to form a mirror profile measuring device. Usually, according to actual requirements, they can be fixed through a connecting frame, or further, the non-contact point displacement sensors 1 and the one-dimensional or two-dimensional scanning sensor 2 can be fixed on equipment such as a numerical control machine tool or a robotic arm to facilitate subsequent control of the measuring device for movement.

[0030] The non-contact point displacement sensor 1 has a large scale and high precision. Therefore, although it can achieve high-precision detection, the limited space will result in a low density of data sampling points. By making equidistant displacement measurements at intervals equal to the distance between the non-contact point displacement sensors 1 on the mirror surface through the non-contact point displacement sensor array, the information of the same position points measured multiple times can be used to calculate the overall surface shape of the mirror with high precision. The measurement accuracy of the one-dimensional or two-dimensional distance sensor 2 is not as high as that of the non-contact point displacement sensor 1, but it has a high data density. Combining with the low-density surface shape obtained by the non-contact point displacement sensor 1, a high-precision and high-data-point-density contour topography of the mirror can be obtained.

[0031] As Figure 2 shown, after the non-contact point displacement sensor array and the one-dimensional or two-dimensional scanning sensor 2 are fixed, it is necessary to calibrate the non-contact point displacement sensors 1 and the one-dimensional or two-dimensional scanning sensor 2 using a standard part 3. Specifically, the standard part 3 can be a standard plane or a standard spherical surface close to the surface shape of the mirror to be detected. The positions of the non-contact point displacement sensors 1 and the one-dimensional or two-dimensional scanning sensor 2 are finely adjusted through the distance data collected by the non-contact point displacement sensors 1 and the one-dimensional or two-dimensional scanning sensor 2 to compensate for the measurement errors of the non-contact point displacement sensors 1 and the one-dimensional or two-dimensional scanning sensor 2 themselves and the errors during the fixing process. When measuring the standard plane, the sampling data of all the non-contact point displacement sensors 1 and the one-dimensional or two-dimensional scanning sensor 2 are made equal by adjustment; when measuring the standard spherical surface, the surface shape obtained by fitting the sampling data of all the non-contact point displacement sensors 1 and the one-dimensional or two-dimensional scanning sensor 2 is made the same as the standard spherical surface by adjustment. This process effectively solves the position fixing errors and the measurement errors of all the non-contact point displacement sensors 1 and the one-dimensional or two-dimensional scanning sensor 2.

[0032] S2: As Figure 3As shown in the figure, according to the single detection range of the measuring device composed of the non-contact point displacement sensor 1 and the one-dimensional or two-dimensional scanning sensor 2 and the size of the mirror 4, the relative motion path is designed, and the measuring device and the mirror 4 are controlled to perform relative motion along the preset relative motion path, so as to realize that the line laser scanning sensor 2 traverses the mirror 4.

[0033] In the process of relative motion control, first, the measuring device composed of the non-contact point displacement sensor 1 and the one-dimensional or two-dimensional scanning sensor 2 can be driven to move along the relative motion path, while the mirror 4 remains stationary, and traversal sampling is realized in this way. Second, the mirror 4 can also be driven to move along the relative motion path, and the measuring device composed of the non-contact point displacement sensor 1 and the one-dimensional or two-dimensional scanning sensor 2 remains stationary to realize traversal sampling. Third, the measuring device and the mirror 4 can also be driven to move simultaneously to realize traversal sampling. Generally, usually the first or second method is selected for motion control, and these two methods are simpler to control and introduce less motion error.

[0034] Correspondingly, during the process of driving relative motion, the traversal method of making the line laser scanning sensor 2 traverse the mirror 4 generally can adopt Figure 4 the polar coordinate rotation method shown in the figure or Figure 5 the XY-axis grating traversal method shown in the figure. These two methods correspond to different relative motion paths respectively. The polar coordinate rotation method has higher detection efficiency but greater control difficulty; the XY-axis grating traversal method has relatively lower detection efficiency but lower control difficulty and higher detection accuracy.

[0035] During the process of the one-dimensional or two-dimensional scanning sensor 2 and the non-contact point displacement sensor array traversing the mirror 4, all the non-contact point displacement sensors 1 and the one-dimensional or two-dimensional scanning sensors 2 collect the distance of the mirror at the same sampling period. The displacements of the non-contact point displacement sensors 1 and the one-dimensional or two-dimensional scanning sensors 2 are the same in each sampling period, that is, the sampling points on the mirror are evenly distributed, and there will be partial overlap of the sampling points of the non-contact point displacement sensor array in two adjacent samplings. The distance data of high-density sampling points on the mirror 4 is obtained through the one-dimensional or two-dimensional scanning sensor 2; the distance data of low-density sampling points on the mirror 4 is obtained through the non-contact point displacement sensor array, and the distance data of each low-density sampling point includes the distance data collected by multiple different non-contact point displacement sensors 1.

[0036] Specifically, as Figure 6As shown, taking the one-dimensional or two-dimensional scanning sensor 2 as the surface displacement sensor and the non-contact point displacement sensor array in the N×N distribution form as an example, for any (n + 1)-th sampling period, the sampling points of the first row of non-contact point displacement sensors 1 in the moving direction in the non-contact point displacement sensor array are new sampling points, and the sampling points of the non-contact point displacement sensors 1 in the remaining rows are the sampling points of the first N - 1 rows of non-contact point displacement sensors 1 in the n-th sampling period, realizing repeated sampling of the distance data of these N - 1 rows of low-density sampling points. In the figure, D1 is the sampling point of a certain non-contact point displacement sensor 1 in the first row in the moving direction in the non-contact point displacement sensor array in the n-th sampling period, and D2 is the sampling point of this non-contact point displacement sensor 1 in the (n + 1)-th sampling period. Similarly for the surface displacement sensor, H1 is a high-density sampling point in a certain square detection area in the n-th sampling period of the surface displacement sensor, and H2 is another high-density sampling point at this sampling position in the (n + 1)-th sampling period of the surface displacement sensor.

[0037] After obtaining the distance data of the high-density sampling points on the mirror 4 through the one-dimensional or two-dimensional scanning sensor 2 and the distance data of the low-density sampling points on the mirror 4 through the non-contact point displacement sensor array, it is necessary to use the distance data of the low-density sampling points for the low-frequency surface shape calculation of the mirror 4. Specifically: based on the principle that the distances collected by different non-contact point displacement sensors for the same low-density sampling point are equal, correct the distance data of the low-density sampling points. For any (n + 1)-th sampling period, the low-density sampling points of the non-contact point displacement sensor array partially overlap with the low-density sampling points in the n-th sampling period. Align the distance data of the overlapping low-density sampling points. The alignment method is: taking the distance data of the low-density sampling points in the n-th sampling period as the standard, compensate and correct the distance data of all low-density sampling points in the (n + 1)-th sampling period, so that the distance data of the overlapping low-density sampling points are equal, that is, when the distance data obtained for the same sampling point in the (n + 1)-th sampling period is different from the distance data of this sampling point in the n-th sampling period, compensate the distance data difference in the distance data in the (n + 1)-th sampling period. For the non-overlapping low-density sampling points, supplement the distance data of the non-overlapping low-density sampling points to the aligned distance data, and iteratively correct the distance data of the low-density sampling points in all sampling periods in this way. The above iterative alignment method is a prior art, and other prior data processing technologies can also be used in addition to this alignment method.

[0038] After the distance data correction process for all low-density sampling points is completed, the high-precision low-density profile of the mirror is obtained by fitting the corrected distance data of all high-precision low-density sampling points. After obtaining the high-precision low-density profile, the distance data of the high-density sampling points on the mirror 4 obtained by the one-dimensional or two-dimensional scanning sensor 2 is fused with the high-precision low-density profile. Specifically, the fusion method can use the high-precision low-density profile as a standard, and the data fusion algorithm is used to correct the distance data of the high-density sampling points and fit them into the high-precision low-density profile to obtain high-precision high-data-density profile data.

[0039] As an alternative embodiment, since motion errors may be introduced when the robotic arm or numerically controlled machine tool drives the measuring device or the mirror 4 to move, during the process of the on-line laser scanning sensor 2 traversing the mirror 4, it is also possible to calibrate the relative motion errors of the non-contact point displacement sensor array and the one-dimensional or two-dimensional scanning sensor 2 with the mirror, and perform motion error compensation on the distance data of the high-density sampling points and the low-density sampling points.

[0040] As an alternative embodiment, the method of the present invention is not only applicable to the measurement of mirrors, but can also be used for the profile measurement of other complex surfaces with relatively small curvature changes.

[0041] In summary, the above description is only a preferred embodiment of this specification and is not intended to limit the protection scope of this specification. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of this specification shall be included within the protection scope of this specification.

[0042] The system, device, module or unit described in the above one or more embodiments can be specifically implemented by a computer chip or entity, or by a product with a certain function. A typical implementation device is a computer. Specifically, the computer can be, for example, a personal computer, a laptop computer, a cellular phone, a camera phone, a smart phone, a personal digital assistant, a media player, a navigation device, an email device, a game console, a tablet computer, a wearable device, or any combination of these devices.

[0043] It should also be noted that the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, commodity or device including a series of elements not only includes those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, commodity or device. Without further limitation, the element defined by the statement "including one..." does not exclude the existence of another identical element in the process, method, commodity or device including the said element.

[0044] Each embodiment in this specification is described in a progressive manner. For the same or similar parts among the embodiments, reference can be made to each other. Each embodiment focuses on the differences from other embodiments. In particular, for system embodiments, since they are basically similar to method embodiments, the description is relatively simple. For related parts, reference can be made to the partial description of method embodiments.

[0045] The above describes specific embodiments of this specification. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recited in the claims can be performed in a different order from that in the embodiments and still achieve the desired result. Additionally, the processes depicted in the drawings do not necessarily require the specific order or sequential order shown to achieve the desired result. In certain embodiments, multitasking and parallel processing are also possible or may be advantageous.

Claims

1. A method for detecting the profile of a large-aperture mirror, characterized in that Including: Constructing a non-contact point displacement sensor array, which includes a plurality of equally spaced non-contact point displacement sensors arranged in the same plane, replacing at least one non-contact point displacement sensor in the non-contact point displacement sensor array with a one-dimensional or two-dimensional scanning sensor, or arranging one of the one-dimensional or two-dimensional scanning sensors between any two non-contact point displacement sensors in the non-contact point displacement sensor array; Making the line laser scanning sensor traverse the mirror. During the traversal process, the one-dimensional or two-dimensional scanning sensor and the non-contact point displacement sensor array periodically collect the distance to the mirror, and the sampling points of the non-contact point displacement sensor array partially overlap in two adjacent samplings; obtaining the distance data of the high-density sampling points on the mirror through the one-dimensional or two-dimensional scanning sensor; obtaining the distance data of the low-density sampling points on the mirror through the non-contact point displacement sensor array, and the distance data of each low-density sampling point includes the distance data collected by multiple different non-contact point displacement sensors; Taking the principle that the distances collected by different non-contact point displacement sensors at the same low-density sampling point are equal, correcting the distance data of the low-density sampling points, and using the corrected distance data of all low-density sampling points to fit and obtain the high-precision low-density profile of the mirror; Fusing the high-density sampling point distance data obtained by the one-dimensional or two-dimensional scanning sensor and the high-precision low-density profile to generate the high-precision high-density profile of the mirror.

2. The large-aperture mirror profile detection method according to claim 1, characterized in that, The one-dimensional or two-dimensional scanning sensor is a line laser scanning sensor or a surface displacement sensor.

3. The large-aperture mirror profile detection method according to claim 1, wherein The length of the single-period detection range of the one-dimensional or two-dimensional scanning sensor is an integer multiple of the distance between adjacent non-contact point displacement sensors.

4. The large-aperture mirror profile detection method according to claim 1, characterized in that Before making the line laser scanning sensor traverse the mirror, it further includes: calibrating the one-dimensional or two-dimensional scanning sensor and the non-contact point displacement sensor using a standard plane or a standard sphere.

5. The large-aperture mirror profile detection method according to claim 1, wherein Presetting the relative movement path between the non-contact point displacement sensor array, the one-dimensional or two-dimensional scanning sensor and the mirror; Driving the non-contact point displacement sensor array and the one-dimensional or two-dimensional scanning sensor to move according to the relative movement path; Or, controlling the mirror to move according to the relative movement path.

6. The large-aperture mirror profile detection method according to claim 1, characterized in that, The traversal method of the line laser scanning sensor traversing the mirror is the polar coordinate rotation method or the XY-axis grating traversal method.

7. The large-aperture mirror profile detection method according to claim 1, characterized in that The sampling times of the one-dimensional or two-dimensional scanning sensor and the non-contact point displacement sensor array are the same.

8. The large-aperture mirror profile detection method according to claim 1, characterized in that, Taking the principle that the distances collected by different non-contact point displacement sensors at the same low-density sampling point are equal, correcting the distance data of the low-density sampling points includes: For any (n + 1)-th sampling period, the low-density sampling points of the non-contact point displacement sensor array partially overlap with the low-density sampling points of the n-th sampling period. Align the distance data of the overlapping low-density sampling points, and supplement the distance data of the non-overlapping low-density sampling points to the aligned distance data, and iteratively correct the distance data of the low-density sampling points of all sampling periods in this way.

9. The large-aperture mirror profile detection method according to claim 8, characterized in that The alignment method is as follows: taking the distance data of the low-density sampling points in the nth sampling period as the standard, compensating and correcting the distance data of all low-density sampling points in the (n + 1)th sampling period, so that the distance data of the overlapping low-density sampling points are equal.

10. The large-aperture mirror profile detection method according to claim 5, characterized in that, It further includes: Calibrating the relative motion errors between the non-contact point displacement sensor array and the one-dimensional or two-dimensional scanning sensor and the mirror during the process of the line laser scanning sensor traversing the mirror, and compensating the motion errors of the distance data of the high-density sampling points and the low-density sampling points.

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