Dual telecentric projection structured light system

Abstract

The present invention discloses a dual telecentric projection structured light system, including a telecentric imaging module, a telecentric projection module, and an image simulation module. The present invention sets a telecentric imaging module, a telecentric projection module, and an image simulation module, and sequentially crosses and connects adjacent A-level marking dots, B-level marking dots, and C-level marking dots in series and parallel to form a three-dimensional marking point network, and makes a three-dimensional image of the object to be measured. The three-dimensional marking point network is used as a three-dimensional data mark of the three-dimensional image to ensure the accuracy of optical three-dimensional measurement; the present invention proposes a dual telecentric structured light system, and both the projection lens and the imaging lens use telecentric lenses, so that the uniformity of the system illumination in the entire area can be ensured; the telecentric projection lens allows the projection light in the entire field of view to be incident on the object to be measured at almost the same angle, so that the accuracy of the structured light system can be ensured even when the object is dynamically moved.

Description

Technical Field

[0001] The present invention relates to the technical field of structured light detection, and in particular to a dual-telecentric projection structured light system. Background Art

[0002] Structured light technology is an optical 3D measurement technology based on triangulation technology. It projects periodic Gray code or sinusoidal stripes at a certain angle, and projects grating stripes in a direction that is at a certain angle to the projected light onto the object to be measured. The light information on the projected object is structured and encoded. The 3D information of the object to be measured is obtained through computer decoding and corresponding algorithms.

[0003] The projection system and imaging system in the structured light system generally use fixed-focus lenses. Whether the projector or the imaging system is tilted, there is a significant problem, that is, the stripe width of the structured light system or the resolution of the camera's imaging system is inconsistent when the measured object is on the left and right sides of the imaging area. This will lead to inconsistent brightness of the structured light system in the entire measurement area; in an ideal structured light system, the width of its projected stripes should be equal throughout the entire field of view, but in the existing structured light system, due to the use of fixed-focus lenses, its projection area is radial, especially if the structured light system is still a tilted projection system, the stripe width of the projection area is inconsistent. In general, because the projection system projects stripe light obliquely, the width of the stripe light on the left and right sides of the field of view is inconsistent, which will cause the system to be in the same plane. The impact caused by this is that the consistency of the full-field measurement accuracy requires more complex correction or calibration; because the angles of the projected light at different positions in the field of view of the general projection system are inconsistent, the dynamic repeatability of the structured light system in measuring narrow-edged objects is poor.

[0004] The existing projection structured light system has poor projection brightness uniformity, inconsistent projection stripe periods, and poor dynamic performance stability of the measurement system. Summary of the invention

[0005] The object of the present invention is to provide a dual telecentric projection structured light system to solve the problems raised in the above background technology.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions: a dual-telecentric projection structured light system, including a cloud service platform, a telecentric imaging module, a telecentric projection module, an image simulation module, a database, a warning module and an intelligent terminal, wherein the output end of the cloud service platform is respectively connected to the telecentric imaging module, the telecentric projection module, the image simulation module, the database and the input end of the intelligent terminal, and the input end of the cloud service platform is respectively connected to the telecentric imaging module, the telecentric projection module, the image simulation module, the database, the warning module and the output end of the intelligent terminal; the cloud service platform performs comprehensive management and control of the system, the telecentric imaging module performs telecentric image data mark point collection directly above the object to be measured, the telecentric projection module performs telecentric projection data mark point collection above the side of the object to be measured, the image simulation module fuses the image and the mark to form a three-dimensional image, and the database is used to store and compare system data; the warning module is used for system warning work; and the intelligent terminal is used to display and set system data.

[0007] Furthermore, the cloud service platform includes a central processing unit and an information transceiver unit, the central processing unit performs comprehensive analysis and processing on the data, and the information transceiver unit performs transceiver processing on the data information.

[0008] Furthermore, the telecentric imaging module includes an imaging dual telecentric lens, a feature marking unit, a marking positioning unit and an image partitioning unit; the imaging dual telecentric lens collects image data directly above the object to be measured, the image partitioning unit performs partitioning processing on the image, the feature marking unit performs feature marking on the image after partitioning, and the marking positioning unit performs three-dimensional positioning processing on the marking point.

[0009] Furthermore, 10 to 12 characteristic A-level marking dots are collected in each partition image, and three characteristic A-level marking dots are located on the boundary of the partition image. A coordinate system is established, and the coordinate position of the A-level marking dots is {(X n ~X m ), (Y n ~Y m )}, the coordinates of the A-level marked dots need to satisfy the condition D<1;

[0010] Furthermore, the imaging dual telecentric lens is a 0.5 lens, and the maximum supported CMOS target surface is 2 / 3.

[0011] Further, the telecentric projection module includes a Sham dual telecentric lens, a marker fitting unit and a marker parsing unit, the Sham dual telecentric lens collects projection data above the side of the object to be measured, the marker fitting unit performs partition fitting and marker fitting on the marker points in the telecentric image data and the projection image; the marker parsing unit decomposes the marker points and further marks them; the projection image contains B-level marker dots and C-level marker dots, and the B-level marker dots overlap with the A-level marker dots and the number is the same;

[0012] The coordinate position of the B-level mark point is {(X n ~X m ), (Y n ~Y m ), (Z n ~Z m )}, the coordinates of the B-level marked dots need to meet the conditions E<1, F<1;

[0013] All C-level marking points are located inside the B-level marking dot. Each B-level marking dot contains four C-level marking points, of which three C-level marking points are located at the outer edge of the B-level marking dot. The above three C-level marking points are distributed in an equilateral triangle with the projection surface as the reference surface, and another C-level marking point is located at the center of the inscribed circle of the equilateral triangle. Then, the C-level marking points are located through imaging images;

[0014] The coordinate position of the C-level marking point is (X i , Y i , Z i ), the coordinates of the C-level mark point need to meet the conditions G <0.5, H<0.5;

[0015] Further, the Sham bi-telecentric lens is L1 biconvex lens, L2 meniscus lens, L3 meniscus lens, L4 double cemented lens, L5 meniscus lens, L6 biconvex lens and L7 meniscus lens from left to right; the area between L7 meniscus lens and DMD is a reserved prism design area; L1 biconvex lens is a biconvex lens with positive focal length, and the focal length of L1 biconvex lens is 80-100mm; L2 meniscus lens is a meniscus lens with positive focal length, and its focal length is 90-100mm; L3 meniscus lens is a meniscus lens with negative focal length, and its focal length is -30--40mm; L4 The double cemented lens is a negative focal meniscus lens formed by cementing a positive and a negative meniscus lens. It is mainly used to control the chromatic aberration of the system. Its focal length is -15 to -25mm. The L5 meniscus lens is a positive focal meniscus lens with a focal length of 40 to 50mm. The L6 biconvex lens is a positive focal biconvex lens with a focal length range of 30 to 40mm. The L7 meniscus lens is a positive power meniscus lens with a focal length of 60 to 70 mm. As a projection lens, a 15 to 30 mm prism space is reserved between the projection chip and the lens. The L1 biconvex lens has a refractive index of 1.5 to 1.7 and an Abbe number of 52 to 58. The L2 meniscus lens has a refractive index of 1.6 to 1.9 and an Abbe number of 42 to 48. The L3 meniscus lens has a refractive index of 1.6 to 1.9 and an Abbe number of 20 to 30. The L4 double cemented lens has a refractive index of 1.7 to 2.0 and an Abbe number of 20 to 35. The L5 The refractive index of the lens material of the meniscus lens is 1.6-1.8, and the Abbe number is 42-47; the refractive index of the material of the L6 biconvex lens is 1.7-1.9, and the Abbe number is 32-36; the refractive index of the material of the L7 meniscus lens is 1.45-1.55, and the Abbe number is 62-66; DMD is a projection chip used for stripe coding of structured light systems.

[0016] Furthermore, the image simulation module includes an image fusion unit and a marker fusion unit. The image fusion unit fits the image data and the projection image data, and the marker fusion unit fuses the image marker points and the projection marker points, cross-connects adjacent marker points in series and parallel in sequence to form a three-dimensional marker point network, and fits the marker point network, the projection image, and the imaging image to achieve three-dimensional image simulation processing, produce a three-dimensional image of the object being measured, and ensure the accuracy of optical three-dimensional measurement.

[0017] Furthermore, the database includes a storage unit, and the storage unit performs cloud storage and local storage on the system data.

[0018] Furthermore, the intelligent terminal includes an input unit and a display unit, the input unit inputs data to the system, and the display unit displays the system data.

[0019] Compared with the prior art, the beneficial effects achieved by the present invention are:

[0020] 1. The present invention sets a telecentric imaging module, a telecentric projection module, and an image simulation module to perform multi-level marking and limitation on the coordinate positions and ranges of the A-level marking dots, the B-level marking dots, and the C-level marking dots, so that the image feature marking accuracy is higher; the adjacent A-level marking dots, the B-level marking dots, and the C-level marking dots are cross-connected in series and parallel in sequence to form a three-dimensional marking point network, and the marking point network, the projected image, and the imaging image are fitted to realize three-dimensional image simulation processing, and a three-dimensional image of the measured object is produced. The three-dimensional marking point network is used as a three-dimensional data label of the three-dimensional image to ensure the optical three-dimensional measurement accuracy.

[0021] 2. The present invention proposes a dual-telecentric structured light system, in which both the projection lens and the imaging lens adopt telecentric lenses, so that the uniformity of the system illumination in the entire area can be ensured; the design of the Sham telecentric projection lens completely eliminates the problem of uneven fringe period in the field of view, which greatly improves the system accuracy; the telecentric projection lens allows the projection light in the entire field of view to be incident on the measured object at almost the same angle, so that the accuracy of the structured light system can be guaranteed even when the object is dynamically moving; in combination with the design of the telecentric imaging lens, the present invention can well control the repeatability of the system; after actual measurement, the static and dynamic repeatability of the structured light system of the present invention is improved by 3-5 times compared with the conventional structured light system with the same field of view. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0023] Figure 1 It is a schematic diagram of module connection in the present invention;

[0024] Figure 2 Schematic diagram of the Sham bi-telecentric lens in the present invention;

[0025] Figure 3 is a modulation transfer function diagram of an example lens in the present invention;

[0026] Figure 4 This is the projection illumination uniformity effect diagram of the conventional projection lens (left) and the Sham telecentric projection lens (right);

[0027] Figure 5 This is a comparison of the fringe period projected by a conventional projection lens (left) and a Sham telecentric projection lens (right);

[0028] Figure 6 This is a schematic diagram comparing conventional structured light (left) and double telecentric structured light (right);

[0029] In the figure: 1. Cloud service platform; 2. Telecentric imaging module; 3. Telecentric projection module; 4. Image simulation module; 5. Database; 6. Warning module; 7. Intelligent terminal; 8. Central processing unit; 9. Information transceiver unit; 10. Imaging dual telecentric lens; 11. Feature marking unit; 12. Marker positioning unit; 13. Image partitioning unit; 14. Sham dual telecentric lens; 15. Marker fitting unit; 16. Marker parsing unit; 17. Image fusion unit; 18. Marker fusion unit; 19. Storage unit; 20. Input unit; 21. Display unit. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] See also Figure 1-Figure 6 The present invention provides a technical solution: a dual telecentric projection structured light system, including a cloud service platform 1, a telecentric imaging module 2, a telecentric projection module 3, an image simulation module 4, a database 5, a warning module 6 and an intelligent terminal 7, wherein the output end of the cloud service platform 1 is respectively connected to the input end of the telecentric imaging module 2, the telecentric projection module 3, the image simulation module 4, the database 5 and the intelligent terminal 7, and the input end of the cloud service platform 1 is respectively connected to the output end of the telecentric imaging module 2, the telecentric projection module 3, the image simulation module 4, the database 5, the warning module 6 and the intelligent terminal 7; the cloud service platform 1 performs comprehensive management and control on the system, the telecentric imaging module 2 performs telecentric image data mark point collection just above the object to be measured, and the telecentric projection module 3 performs telecentric image data mark point collection just above the object to be measured Telecentric projection data mark point collection is performed on the upper side of the object, the image simulation module 4 fuses the image and the mark to form a three-dimensional image, and the database 5 is used to store and compare the system data; the warning module 6 is used for system warning work; the intelligent terminal 7 is used to display and set the system data; the telecentric imaging module 2 includes an imaging dual telecentric lens 10, a feature marking unit 11, a mark positioning unit 12 and an image partitioning unit 13; the imaging dual telecentric lens 10 performs image data collection directly above the object to be measured, the image partitioning unit 13 performs partition processing on the image, the feature marking unit 11 performs feature marking on the image after partitioning, and the mark positioning unit 12 performs three-dimensional positioning processing on the mark point;

[0032] In each partition image, 10 to 12 characteristic A-level marking dots are collected. Three characteristic A-level marking dots are located on the boundary of the partition image. A coordinate system is established. The coordinate position of the A-level marking dots is {(X n ~X m ), (Y n ~Y m )}, the coordinates of the A-level marked dots need to satisfy the condition D<1;

[0033] The telecentric projection module 3 includes a Sham dual telecentric lens 14, a marker fitting unit 15 and a marker parsing unit 16. The Sham dual telecentric lens 14 collects projection data above the side of the object to be measured. The marker fitting unit 15 performs partition fitting and marker fitting on the marker points in the telecentric image data and the projection image; the marker parsing unit 16 decomposes the marker points for further marking; the projection image contains B-level marker dots and C-level marker dots, and the B-level marker dots overlap with the A-level marker dots and the number is the same;

[0034] The coordinate position of the B-level mark point is {(X n ~X m ), (Y n ~Y m ), (Z n ~Z m )}, the coordinates of the B-level marked dots need to meet the conditions E<1, F<1;

[0035] All C-level marking points are located inside the B-level marking dot. Each B-level marking dot contains four C-level marking points, of which three C-level marking points are located at the outer edge of the B-level marking dot. The above three C-level marking points are distributed in an equilateral triangle with the projection surface as the reference surface, and another C-level marking point is located at the center of the inscribed circle of the equilateral triangle. Then, the C-level marking points are located through imaging images;

[0036] The coordinate position of the C-level marking point is (X i , Y i , Z i ), the coordinates of the C-level mark point need to meet the conditions G <0.5, H<0.5;

[0037] The image simulation module 4 includes an image fusion unit 17 and a marker fusion unit 18. The image fusion unit 17 fits the image data and the projection image data, and the marker fusion unit 18 fuses the image marker points and the projection marker points, cross-connects the adjacent marker points in series and parallel in sequence to form a three-dimensional marker point network, fits the marker point network with the projection image and the imaging image, realizes three-dimensional image simulation processing, and produces a three-dimensional image of the object to be measured, thereby ensuring the accuracy of optical three-dimensional measurement.

[0038] The Sham bi-telecentric lens 14 is composed of L1 biconvex lens, L2 meniscus lens, L3 meniscus lens, L4 double cemented lens, L5 meniscus lens, L6 biconvex lens and L7 meniscus lens from left to right; the area between L7 meniscus lens and DMD is a reserved prism design area; L1 biconvex lens is a biconvex lens with positive focal length, and the focal length of L1 biconvex lens is 80-100mm; L2 meniscus lens is a meniscus lens with positive focal length, and its focal length is 90- 100mm, L3 meniscus lens is a meniscus lens with negative focal power, and its focal length is -30~-40mm, L4 double cemented lens is a meniscus lens with negative focal power formed by cementing a positive and a negative meniscus lens, mainly to control the chromatic aberration of the system, and its focal length is -15~-25mm; L5 meniscus lens is a meniscus lens with positive focal power, and its focal length is 40~50mm, L6 biconvex lens is a biconvex lens with positive focal power, and its focal length range is between 30~40mm; The L7 meniscus lens is a positive-power meniscus lens with a focal length of 60 to 70 mm. As a projection lens, a 15 to 30 mm prism space is reserved between the projection chip and the lens. The material of the L1 biconvex lens has a refractive index of 1.5 to 1.7 and an Abbe number of 52 to 58. The refractive index of the L2 meniscus lens is in the range of 1.6 to 1.9 and the Abbe number is 42 to 48. The material refractive index of the L3 meniscus lens is 1.6 to 1.9 and the Abbe number is 20 to 30. The refractive index of the two lenses of the L4 double-cemented lens is 1.7 to 2.0 and the Abbe number is 20 to 35. The refractive index of the lens material of the L5 meniscus lens is 1.6 to 1.8 and the Abbe number is 42 to 47. The refractive index of the L6 biconvex lens is 1.7 to 1.9, Abbe number is 32-36; L7 meniscus lens has a material refractive index of 1.45-1.55, and an Abbe number of 62-66; DMD is a projection chip used for fringe coding in structured light systems;

[0039] Specific examples of Sham bi-telecentric lenses are shown in the following table:

[0040]

[0041]

[0042] The system modulation function obtained for the example Sham bi-telecentric lens is as follows Figure 3shown.

[0043] The cloud service platform 1 includes a central processing unit 8 and an information transceiver unit 9. The central processing unit 8 performs comprehensive analysis and processing on data, and the information transceiver unit 9 performs transceiver processing on data information.

[0044] The imaging dual telecentric lens 10 is a 0.5 lens, and the maximum supported CMOS target surface is 2 / 3.

[0045] The database 5 includes a storage unit 19 , and the storage unit 19 performs cloud storage and local storage for system data.

[0046] The intelligent terminal 7 includes an input unit 20 and a display unit 21. The input unit 20 inputs data to the system, and the display unit 21 displays the system data.

[0047] The specific implementation method is as follows: the present invention sets a telecentric imaging module 2, a telecentric projection module 3, and an image simulation module 4. The telecentric imaging module 2 positions the object features in the X-axis and Y-axis directions as an A-level marking dot directly above the object to be measured; the telecentric projection module 3 positions the object features in the X-axis, Y-axis and Z-axis directions as a B-level marking dot above the side of the object to be measured, and analyzes and marks the B-level marking dot as a C-level marking dot; and the coordinate positions and ranges of the A-level marking dot, the B-level marking dot and the C-level marking dot are multi-level marked and limited, so that during the image acquisition process, the A-level marking dot preliminarily marks the features of the object to be measured, and the B-level marking dot further calibrates the A-level marking dot, thereby improving the calibration accuracy of the features of the object to be measured. The C-level marking points analyze and re-mark the B-level marking points, so that the features of the object to be measured inside the B-level marking points are clearer, and the marking accuracy of the features inside the B-level marking points is higher; the adjacent A-level marking points, B-level marking points and C-level marking points are cross-connected in series and parallel in sequence to form a three-dimensional marking point network, and the marking point network and the projection image and the imaging image are fitted to realize three-dimensional image simulation processing to produce a three-dimensional image of the object to be measured. The three-dimensional marking point network is used as a three-dimensional data marker of the three-dimensional image to ensure the optical three-dimensional measurement accuracy; the present invention proposes a dual-telecentric structured light system, and both the projection lens and the imaging lens adopt telecentric lenses, so that the system can ensure The uniformity of systematic illumination in the entire area; the design of the Sham telecentric projection lens adopted in the present invention completely eliminates the problem of uneven fringe period in the field of view, which greatly improves the accuracy of the system; the telecentric projection lens designed in accordance with Sham's law in the present invention allows the projection light in the entire field of view to be incident on the measured object at almost the same angle, which can ensure the accuracy of the structured light system even when the object is dynamically moved; DMD is a projection chip used for fringe encoding of the structured light system; both the object side and the image side are designed as telecentric systems, and the advantage of such a design is that it can ensure the uniformity of brightness in the projection area, and its illumination uniformity is better than that of conventional projection systems, such as Figure 4 As shown; because the projection lens is designed to comply with Sham's law, compared with traditional lenses, the projection stripes can be clearer in the entire field of view; also because the bi-telecentric projection lens is designed to comply with Sham's law, the period of the stripes in the projection range basically does not change, the projection diagram Figure 5As shown in the figure, since the projection lens is a telecentric lens that complies with Sham's law, the angle of the light it projects is very consistent, thus ensuring the consistency of the projection period; the light projected by conventional structured light is radial, which will cause the width of the stripes in the area of ​​position A and position C to be inconsistent. At the same time, since the imaging system of conventional structured light is a fixed-focus system, the widths of objects A, B, and C with the same width but different heights on the image sensor are also different sizes. Although it can be corrected through some system calibration, its accuracy cannot be guaranteed; the most critical thing is that when A and C After the positions are interchanged, due to the changes in the projection stripe width and the imaging area, the measured width and height values ​​of A and C are different from the original ones; this will lead to poor dynamic repeatability of the system; and in the present invention, the designed dual telecentric projection lens that conforms to Sham's law can well ensure that the angle of the projection light is consistent, so that it can ensure that the angle of the light received by objects at different heights is consistent; at the same time, because it is a telecentric projection lens, it can ensure that the stripe width of the projection area is consistent, and the height values ​​obtained by decomposing the phases at different fields of view of objects at the same height can also ensure consistency; with the design of the telecentric imaging lens, the present invention can well control the repeatability of the system; after actual measurement, the static and dynamic repeatability of the structured light system of the present invention is improved by 3-5 times compared with the conventional structured light system with the same field of view.

[0048] Working principle of the present invention:

[0049] Refer to the instruction manual Figure 1-6 The present invention sets a telecentric imaging module 2, a telecentric projection module 3, and an image simulation module 4 to perform multi-level marking and limitation on the coordinate positions and ranges of the A-level marking dots, the B-level marking dots, and the C-level marking dots, so that the image feature marking accuracy is higher; the adjacent A-level marking dots, The B-level marking dots and the C-level marking dots are cross-connected in series and parallel in sequence to form a three-dimensional marking point network, and the marking point network, the projection image and the imaging image are fitted to realize three-dimensional image simulation processing, and a three-dimensional image of the measured object is made. The three-dimensional marking point network is used as a three-dimensional data marker of the three-dimensional image to ensure the accuracy of optical three-dimensional measurement; the present invention proposes a dual-telecentric structured light system, and both the projection lens and the imaging lens adopt telecentric lenses, so that the uniformity of the system illumination in the entire area can be ensured; the design of the Sham telecentric projection lens completely eliminates the problem of uneven periodicity of stripes in the field of view, which greatly improves the accuracy of the system; the telecentric projection lens allows the projection light in the entire field of view to be incident on the measured object at almost the same angle, so that the accuracy of the structured light system can be guaranteed even when the object is dynamically moved; in combination with the design of the telecentric imaging lens, the present invention can well control the repeatability of the system; after actual measurement, the static and dynamic repeatability of the structured light system of the present invention is improved by 3-5 times compared with the conventional structured light system with the same field of view.

[0050] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0051] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A dual telecentric projection structured light system, comprising a cloud service platform (1), a telecentric imaging module (2), a telecentric projection module (3), an image simulation module (4), a database (5), a warning module (6) and an intelligent terminal (7), characterized in that: The output end of the cloud service platform (1) is respectively connected to the input end of the telecentric imaging module (2), the telecentric projection module (3), the image simulation module (4), the database (5) and the intelligent terminal (7); the input end of the cloud service platform (1) is respectively connected to the output end of the telecentric imaging module (2), the telecentric projection module (3), the image simulation module (4), the database (5), the warning module (6) and the intelligent terminal (7); the cloud service platform (1) performs comprehensive management and control on the system; the telecentric imaging module (2) collects telecentric image data marker points directly above the object to be measured; the telecentric projection module (3) collects telecentric projection data marker points above the side of the object to be measured; the image simulation module (4) fuses the image and the marker to form a three-dimensional image; The database (5) is used for storing and comparing system data; the warning module (6) is used for system warning work; the intelligent terminal (7) is used for displaying and setting system data; the telecentric imaging module (2) includes an imaging dual telecentric lens (10), and the imaging dual telecentric lens (10) collects image data directly above the object to be measured; the telecentric projection module (3) includes a Sham dual telecentric lens (14), and the Sham dual telecentric lens (14) collects projection data above the side of the object to be measured; the image simulation module (4) includes a marker fusion unit (18), and the marker fusion unit (18) performs fusion processing on image marker points and projection marker points, and sequentially cross-connects adjacent marker points in series and parallel to form a three-dimensional marker point network.

2. The dual telecentric projection structured light system according to claim 1, characterized in that: The cloud service platform (1) comprises a central processing unit (8) and an information transceiver unit (9); the central processing unit (8) performs comprehensive analysis and processing on data, and the information transceiver unit (9) performs transceiver processing on data information.

3. The dual telecentric projection structured light system according to claim 1, characterized in that: The telecentric imaging module (2) further comprises a feature marking unit (11), a mark positioning unit (12) and an image partitioning unit (13); the image partitioning unit (13) performs partitioning processing on the image, the feature marking unit (11) performs feature marking on the partitioned image, and the mark positioning unit (12) performs three-dimensional positioning processing on the marking point.

4. The dual telecentric projection structured light system according to claim 3, characterized in that: In each partition image, 10 to 12 characteristic A-level marking dots are collected. Three characteristic A-level marking dots are located on the boundary of the partition image. A coordinate system is established. The coordinate position of the A-level marking dots is {(X n ~X m ), (Y n ~Y m )}, the coordinates of the A-level marked dots need to meet the conditions D<1; D= .

5. The dual telecentric projection structured light system according to claim 3, characterized in that: The imaging dual telecentric lens (10) is a 0.5 lens, and the maximum supported CMOS target surface is 2 / 3.

6. The dual telecentric projection structured light system according to claim 4, characterized in that: The telecentric projection module (3) further comprises a marker fitting unit (15) and a marker parsing unit (16), wherein the marker fitting unit (15) performs partition fitting and marker fitting on the marker points in the telecentric image data and the projection image; and the marker parsing unit (16) decomposes the marker points and further marks them; The projected image contains B-level marking dots and C-level marking dots, and the B-level marking dots overlap with the A-level marking dots and the number is the same; The coordinate position of the B-level mark point is {(X n ~X m ), (Y n ~Y m ), (Z n ~Z m )}, the coordinates of the B-level marked dots need to meet the conditions E<1, F<1; E= ,F= ; All C-level marking points are located inside the B-level marking dot. Each B-level marking dot contains four C-level marking points, of which three C-level marking points are located at the outer edge of the B-level marking dot. The above three C-level marking points are distributed in an equilateral triangle with the projection surface as the reference surface, and another C-level marking point is located at the center of the inscribed circle of the equilateral triangle. Then, the C-level marking points are located through imaging images; The coordinate position of the C-level marking point is (X i , Y i , Z i ), the coordinates of the C-level mark point need to meet the conditions G<0.5, H<0.5; G= , H = .

7. The dual telecentric projection structured light system according to claim 6, characterized in that: The Sham bi-telecentric lens (14) comprises, from left to right, an L1 biconvex lens, an L2 meniscus lens, an L3 meniscus lens, an L4 double cemented lens, an L5 meniscus lens, an L6 biconvex lens and an L7 meniscus lens; a prism design area is reserved between the L7 meniscus lens and the DMD; the L1 biconvex lens is a biconvex lens with a positive focal length, and the focal length of the L1 biconvex lens is 80-100 mm; the L2 meniscus lens is a meniscus lens with a positive optical power, and its focal length is 90-100 mm , L3 meniscus lens is a meniscus lens with negative focal power, and its focal length is -30~-40mm, L4 double cemented lens is a meniscus lens with negative focal power formed by cementing a positive and a negative meniscus lens, mainly to control the chromatic aberration of the system, and its focal length is -15~-25mm; L5 meniscus lens is a meniscus lens with positive focal power, and its focal length is 40~50mm, L6 biconvex lens is a biconvex lens with positive focal power, and its focal length range is between 30~40mm; L7 The meniscus lens is a positive-power meniscus lens with a focal length of 60 to 70 mm. As a projection lens, a 15 to 30 mm prism space is reserved between the projection chip and the lens. The material of the L1 biconvex lens has a refractive index of 1.5 to 1.7 and an Abbe number of 52 to 58. The refractive index of the L2 meniscus lens is in the range of 1.6 to 1.9 and an Abbe number of 42 to 48. The refractive index of the L3 meniscus lens is in the range of 1.6 to 1.9 and an Abbe number of 20 to 58. 30; The refractive index of the two lenses of the L4 double cemented lens is 1.7~2.0, and the Abbe number is 20~35; The refractive index of the lens material of the L5 meniscus lens is 1.6~1.8, and the Abbe number is 42~47; The refractive index of the material of the L6 double convex lens is 1.7~1.9, and the Abbe number is 32~36; The refractive index of the material of the L7 meniscus lens is 1.45~1.55, and the Abbe number is 62~66; DMD is a projection chip used for stripe coding of structured light systems.

8. The dual telecentric projection structured light system according to claim 1, characterized in that: The image simulation module (4) further comprises an image fusion unit (17), wherein the image fusion unit (17) performs fitting on the image data and the projection image data, and the marker fusion unit (18) further performs fitting processing on the marker point network, the projection image and the imaging image, thereby achieving three-dimensional image simulation processing, producing a three-dimensional image of the object to be measured, and ensuring the accuracy of optical three-dimensional measurement.

9. The dual telecentric projection structured light system according to claim 1, characterized in that: The database (5) comprises a storage unit (19), and the storage unit (19) performs cloud storage and local storage on system data.

10. The dual telecentric projection structured light system according to claim 1, characterized in that: The intelligent terminal (7) comprises an input unit (20) and a display unit (21); the input unit (20) inputs data into the system, and the display unit (21) displays the system data.

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