Method, device and system for three-dimensional reconstruction of transparent objects

Abstract

The present application relates to a method, device and system for three-dimensional reconstruction of transparent objects. The system comprises a structured light generation module, an image acquisition module, a control module and a calculation module. The calculation module acquires image pairs from the image acquisition module; calculates the three-dimensional position of points according to the image pairs; and performs a refinement process to extract the front reflection points. The refinement process comprises: when the reflection points are acquired by the first camera, the reflection points include first reflection points and second reflection points, the first reflection points are closer to the laser reflection point on the galvanometer than the second reflection points, and the second reflection points are removed; when the first reflection points are not acquired by the second camera, the first reflection points are removed; when the second reflection points are acquired by the second camera, the second reflection points are retrieved, and when discrete external virtual contours are formed, the discrete external virtual contours are removed.

Description

Technical Field

[0001] This invention relates to the field of three-dimensional reconstruction, and more particularly to methods, apparatus and systems for three-dimensional reconstruction of transparent objects. Background Technology

[0002] In conventional 3D reconstruction techniques, 3D objects are reconstructed by scanning their surfaces with lasers, collecting reflection points from the surface, and calculating the positions of these points. 3D models can be built based on points with known locations. However, reconstructing transparent objects presents significant challenges due to the complexities of laser transmission within them. Summary of the Invention

[0003] According to various embodiments of the present invention, methods, apparatus and systems for three-dimensional reconstruction of transparent objects are provided.

[0004] A method for three-dimensional reconstruction of transparent objects using laser scanning, the method comprising:

[0005] When the reflection point is acquired by the first camera, the reflection point includes a first reflection point and a second reflection point. The first reflection point is closer to the laser reflection point on the galvanometer than the second reflection point. The second reflection point is then removed.

[0006] When the first reflection point is not captured by the second camera, the first reflection point is removed; and

[0007] When the second reflection point is obtained through the second camera, the second reflection point is retrieved.

[0008] An apparatus for three-dimensional reconstruction of transparent objects using laser scanning, comprising:

[0009] Processor; and

[0010] Non-transitory computer-readable medium attached to and storing thereon instructions for causing the processor to perform the following operations:

[0011] When the reflection point is acquired by the first camera, the reflection point includes a first reflection point and a second reflection point. The first reflection point is closer to the laser reflection point on the galvanometer than the second reflection point. The second reflection point is then removed.

[0012] When the first reflection point is not captured by the second camera, the first reflection point is removed; and

[0013] When the second reflection point is obtained through the second camera, the second reflection point is retrieved.

[0014] A system for 3D reconstruction of transparent objects using laser scanning, comprising:

[0015] A structured light generation module that emits a laser beam toward an object and allows the laser to scan the surface of the object being measured;

[0016] An image acquisition module includes a first camera and a second camera, which collect feedback image pairs by capturing laser light reflected from the object;

[0017] The control module is responsible for synchronizing the structured light generation module and the image acquisition module; and

[0018] The calculation module acquires the image pairs from the image acquisition module; calculates the three-dimensional position of the points based on the image pairs; and performs thinning processing to extract the front reflection points.

[0019] The refinement process includes:

[0020] When the reflection point is obtained through the first camera, the reflection point includes a first reflection point and a second reflection point. The first reflection point is closer to the laser reflection point on the galvanometer than the second reflection point. The second reflection point is then removed.

[0021] When the first reflection point is not captured by the second camera, the first reflection point is removed; and

[0022] When the second reflection point is obtained through the second camera, the second reflection point is retrieved.

[0023] Details of one or more embodiments of the present invention will be set forth in the following description and accompanying drawings. Other features, objects, and advantages of the invention will become apparent from the description, drawings, and claims. Attached Figure Description

[0024] To better describe and illustrate embodiments and / or examples of the content disclosed in this invention, reference may be made to one or more accompanying drawings. Additional details or examples used to describe the drawings should not be construed as limiting the scope of any disclosure, the currently described embodiments and / or examples, or the best implementation of these contents as currently understood.

[0025] Figure 1 A schematic diagram of a system for three-dimensional reconstruction of transparent objects provided in an embodiment of the present invention;

[0026] Figure 2 This is a schematic diagram of a first camera according to an embodiment of the present invention;

[0027] Figure 3 This is a schematic diagram of a second camera according to an embodiment of the present invention;

[0028] Figure 4 This is a schematic diagram illustrating the calibration model of the galvanometer according to an embodiment of the present invention;

[0029] Figure 5 This is a flowchart of a method applied in a system according to an embodiment of the present invention;

[0030] Figure 6 This is a flowchart of a method applied to a system according to another embodiment of the present invention;

[0031] Figure 7 This is a flowchart of a detailed process according to an embodiment of the present invention;

[0032] Figure 8 This is a flowchart of a detailed process according to another embodiment of the present invention;

[0033] Figure 9 This is a diagram illustrating the optical path analysis of step S162 according to an embodiment of the present invention;

[0034] Figure 10 This is a schematic diagram illustrating a situation with points of ambiguity;

[0035] Figure 11 This is a diagram illustrating another situation with points of ambiguity;

[0036] Figure 12 This is a diagram illustrating the optical path analysis of step S164 according to an embodiment of the present invention;

[0037] Figure 13 This is a diagram illustrating the optical path analysis of step S166 according to an embodiment of the present invention;

[0038] Figure 14 This is a diagram illustrating a situation with highly ambiguous points;

[0039] Figure 15 This is a diagram illustrating the optical path analysis of step S168 according to an embodiment of the present invention;

[0040] Figure 16 This is a flowchart of a method for three-dimensional reconstruction of a transparent object according to an embodiment of the present invention;

[0041] Figure 17 This is a flowchart of a method for three-dimensional reconstruction of a transparent object according to another embodiment of the present invention;

[0042] Figure 18 This is a flowchart of a method for three-dimensional reconstruction of a transparent object according to another embodiment of the present invention;

[0043] Figure 19 This is a schematic diagram of the structure of a device for three-dimensional reconstruction of transparent objects according to an embodiment of the present invention;

[0044] Figure 20 It's a photo of a plastic funnel;

[0045] Figure 21 yes Figure 20 The reconstruction result of the plastic funnel shown;

[0046] Figure 22 It's a photo of water bottles stacked together;

[0047] Figure 23 yes Figure 22 The result of the reconstruction of the stacked water bottles is shown. Detailed Implementation

[0048] To facilitate understanding of the present invention, a more comprehensive description is provided below in conjunction with the accompanying drawings. Preferred embodiments of the invention are shown in the drawings. However, the invention can be embodied in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to make the description of the invention more thorough and complete.

[0049] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. These definitions are provided to aid in the description of particular embodiments and not to limit the claimed invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0050] To provide a more thorough understanding of the present invention, detailed steps and structures will be provided below to explain the technical solution proposed by the present invention. Preferred embodiments of the present invention will be described in detail below. However, in addition to these details, other embodiments of the present invention may exist.

[0051] refer to Figure 1 The 3D reconstruction system 10 includes a structured light generation module 110, an image acquisition module 120, a control module 130, and a calculation module 140. The system 10 can reconstruct the outer surface of a transparent object 20. The transparent object 20 can be completely transparent, semi-transparent, or partially transparent.

[0052] The structured light generation module 110 emits a laser beam toward the object 20 and allows the laser to scan the surface of the object 20 to be measured. In some embodiments, the structured light generation module 110 includes a laser source 112 and a galvanometer 114. The laser source 112 emits the laser beam onto the galvanometer, and the galvanometer reflects the laser beam onto the object 20. In other embodiments, the structured light generation module 110 may also be other directionally controllable laser devices. In this embodiment, the galvanometer 114 has a single-axis rotation capability, which reflects the laser beam onto the object 20 to be reconstructed to form a design feature. The laser beam scans the surface to be measured by rotating the galvanometer 114 to continuously preset angles. The galvanometer 114 reflects the laser beam onto the object 20 to be reconstructed to form a design feature. In this embodiment, the shape of the laser beam is a straight line. In other embodiments, the shape of the laser beam may be a dot or a curve.

[0053] The image acquisition module 120 includes a first camera 122 and a second camera 124, which collect feedback image pairs by capturing laser light reflected from the object 20. The image acquisition module 120 can transmit the images to the computing module 140. (Reference) Figure 2 and Figure 3 In some embodiments, the first camera 122 includes a first camera body 122a and a first filter 1222, and the first camera body 122a includes a first image sensor 1224 and a first optical lens 1226. The first camera 122 includes the first image sensor 1224, the first optical lens 1226, and the first filter 1222, with the first optical lens 1226 located between the first image sensor 1224 and the first filter 1222. Figure 1 and Figure 3 As shown, the second camera 124 includes a second camera body 124a and a second filter 1242, and the second camera body 124a includes a second image sensor 1244 and a second optical lens 1246. The second camera 124 includes a second image sensor 1244, a second optical lens 1246, and a second filter 1242, with the second optical lens 1246 located between the second image sensor 1244 and the second filter 1242. The wavelength of the laser is matched to the passing wavelengths of the first filter 1222 and the second filter 1242. The first filter 1222 and the second filter 1242 allow the laser to reach the first optical lens 1226 and the second optical lens 1246, avoiding stray light interference.

[0054] The control module 130 is responsible for synchronizing the structured light generation module 110 and the image acquisition module 120. In some embodiments, the control module 130 can synchronize the structured light generation module 110 and the image acquisition module 120 through pulse modulation.

[0055] The computing module 140 is responsible for analyzing and processing data to reconstruct the outer surface of the object 20. The laser plane reflected by the galvanometer 114 of the system 10 is modeled according to the principle of light path propagation.

[0056] In some embodiments, the system 10 includes a calibration procedure. (See reference...) Figure 4 , Figure 4 The calibration model of galvanometer 114 is shown. First, the rotation center axis of galvanometer 114 is taken as the z-axis. Second, the x-axis is parallel to the incident plane π1 of the line laser and perpendicular to the z-axis. α represents the reflecting plane π of galvanometer 114. s The angle between the line laser incident plane π1 and the y-axis. Ideally, the line laser incident plane π1 intersects the z-axis. Considering installation misalignment, two parameters γ and d are created to correct for this misalignment. γ represents the angle between the intersection of π1 and the YOZ plane and the z-axis. π1 intersects the y-axis at the point (0, d, 0). Therefore, the line laser incident plane π1 can be represented as:

[0057] π1:y-tan(γ)zd=0 (1)

[0058] The reflecting plane π of galvanometer 114 s Represented as:

[0059] π s :cos(α)x-sin(α)y=0 (2)

[0060] According to the Haushold transform, the reflection matrix H can be calculated as:

[0061]

[0062] The normal vector of the reflected laser plane π1 can be determined as:

[0063]

[0064] The normal vector of the reflected laser plane π2 can be derived as:

[0065]

[0066] The reflected laser plane π2 intersects with point t(dtan(α), d, 0). Therefore, the reflected laser plane π2 can be obtained as follows:

[0067] π2:sin(2α)x s-cos(2α)y s -tan(γ)z s -d=0 (6)

[0068] Assuming the rotation vector Translation vector This is a transformation from the camera coordinate system to the galvanometer 114 coordinate system. Therefore, the point (x) in the camera coordinate system... c ,y c ,z c (x) to the point in the galvanometer 114 coordinate system s ,y s ,z s The conversion relationship is shown below:

[0069]

[0070] in:

[0071] The coordinate system of the galvanometer 114 is not completely constrained and can move along the rotation center axis of the galvanometer 114. The coordinate system of the galvanometer 114 can be fixed by making t3 = 0. The angle α can be controlled by inputting the current value I, as shown in equation (8), where k represents the linear increase angle per unit current and α0 represents the initial bias angle.

[0072] α(I)=kI+α0 (8)

[0073] A total of nine independent unknown parameters describe the galvanometer 114 model without positional assumptions. Assembly errors are also considered in the mathematical model. These nine independent unknown parameters can be predicted by minimizing the following objective function:

[0074]

[0075] in, It is sampling point P ij To the predicted reflective laser plane The distance. X consists of 9 independent parameters to be optimized.

[0076] In summary, the calibration process of system 10, including galvanometer 114, first camera 122, and second camera 124 (dual camera), is described as follows:

[0077] First, the chessboard is placed in different positions and captured by dual cameras, eliminating the need for laser scanning.

[0078] Secondly, the images captured by the dual cameras are calibrated, including the calibration of intrinsic parameters, extrinsic parameters, and distortion coefficients.

[0079] Third, the planar target is placed in different positions and captured by dual cameras through laser scanning.

[0080] Fourth, laser stripe feature points are extracted and reconstructed using binocular triangulation with the help of dual cameras.

[0081] Fifth, nine independent parameters are estimated based on equation (9).

[0082] Then, the calibration of the system 10 is completed.

[0083] refer to Figure 5 The calculation module 140 performs the following steps:

[0084] Step S120: Acquire image pairs from image acquisition module 120.

[0085] Step S140: Calculate the three-dimensional position of the point based on the image.

[0086] Step S160: Perform refinement processing to extract the front reflection point.

[0087] Then, obtain the 3D point cloud.

[0088] The various scenarios of laser transmission inside the transparent object 20 are analyzed, and the reconstructed 3D laser candidate points are divided into two categories: front reflection points and non-front reflection points. The front reflection points refer to the laser reflection points on the front surface of the object 20 under test.

[0089] refer to Figure 6 In some embodiments, the computing module 140 executes step S110 before step S120:

[0090] Step S110: Execute the calibration procedure.

[0091] The calibration process is as described above. After executing the calibration procedure, the accuracy of the output will be improved.

[0092] Specifically, refer to Figure 7 The refinement process includes:

[0093] Step S162: When multiple points are obtained through the first camera 122, these points include a first reflection point and a second reflection point. The first reflection point is closer to the laser reflection point on the galvanometer 114 than the second reflection point. The second reflection point is then removed.

[0094] Step S164: When the first reflection point is not obtained through the second camera 124, the first reflection point is removed.

[0095] Step S166: When the second reflection point is obtained through the second camera 124, the second reflection point is retrieved.

[0096] For each row of the image, the number of the first reflection points is one. The number of the second reflection points can be one or more.

[0097] In some embodiments, in step S166, if the second camera 124 acquires two or more points, the second reflection point is closer to the laser beam than the other points. Galvanometer The reflection point on 114.

[0098] refer to Figure 8 In some embodiments, the computing module 140 further performs the following steps after step S166:

[0099] Step S168: A virtual contour is formed by using the points acquired in the above steps when the laser moves; when a discrete external virtual contour is formed, the discrete external virtual contour is removed.

[0100] The refinement process can reconstruct the outer surface of a transparent object 20 with an unknown interior. The refinement process extracts the front reflection points through optical geometric constraints. In step S162, a single camera can remove spurious points; in step S164, ambiguous points can be removed through joint constraints of two cameras; in step S166, lost front reflection outer surface points can be recovered through fusion; and in step S168, severely ambiguous points can be removed through contour continuity.

[0101] refer to Figure 9 In step S162, false points are removed using a single camera. To achieve false point removal using a single camera (first camera 122), the optical path is first analyzed, such as... Figure 9 As shown. When the reflection point g on the galvanometer 114 projects the laser beam onto the surface point p on the outer surface of the object under test 20, part of the light passes through the ray beam. The light is directly reflected into the first camera 122 via diffuse reflection. The remaining light is refracted into the transparent object 20, reflected by the back surface at point p′, and finally passes through the ray. The incident laser plane π2 is known based on the previous calibration results. The ray can be determined by extracting characteristic laser points from the image of the first camera 122. and Candidate points p and p can be calculated using triangulation. * (First reflection point and second reflection point).

[0102] When the candidate points p and p are collected * At that time, the false point p can be removed by this constraint equation Eq.(10). * Click TP li (The real point) is retained by step S162.

[0103] p * =max p,p* (gp,gp * (10)

[0104] The fake point p * Point p is farther from the reflection point g than point p. According to step S162, remove the false point p. * .

[0105] However, there are two situations where ambiguity cannot be correctly removed. For example... Figure 10 and 11 As shown, due to the refraction and reflection of the laser inside the transparent object 20, the non-front reflection point may include a laser point p′ reflected from the back surface and some permanent light spots p located on the outer surface. s The laser spot p′ may be generated by specular reflection on the rear surface of the object 20 being measured. The permanent light spot p is generated on the outer surface due to complex cross-reflections within the transparent object 20. s And it remains stationary when the laser moves, such as Figure 11 The dashed line in the diagram shows this. In both cases, the outward reflection point p is removed, and the ambiguous point p... * The constrained equation Eq.(10) is incorrectly retained. To resolve this ambiguity, steps S164 and S166 are used to remove the ambiguous point p. * And find the external point p of the front reflection.

[0106] To ensure the reliability of the reconstructed points, the ambiguous point p * Removed via step S164. For example... Figure 12 As shown, images from the second camera 124 are considered to provide second-viewpoint information. For the second camera 124, the ambiguity point p... * The center C of the second camera 124 r Another ray formed between them. The second camera 124 does not receive the light intensity passing through the optical path. Therefore, the second camera 124 cannot capture the ambiguous point p. * These are categorized as characteristic laser points. The retained true points TP... li The image is then reprojected onto the plane of the second camera 124, as shown below:

[0107] tp ri =reproject(TP) li C r (11)

[0108] Through this reprojection, point tp is obtained in the plane of the second camera 124. riThe 2D coordinates of . Then, by determining tp ri Is it a feature laser point to remove ambiguous points p? * As shown in equation (12), the ambiguous point p is removed by reprojection and re-judgment on the plane of the second camera 124. * Thus, CTP is obtained. li (Make it as true as possible.)

[0109]

[0110] In step S162, this ambiguity results in the removal of the outward reflection point p, and the ambiguous point p... * Reserved by mistake, such as Figure 10 and Figure 11 As shown. Step S164 removes ambiguous points p by reprojecting and re-judging on the plane of the second camera 124. * In step S166, the front reflection point p is retrieved by fusing the view from the second camera 124.

[0111] like Figure 13 As shown, the point p removed by the first camera 122 in step S162 can be retrieved by the second camera 124. In the view of the second camera 124, the front reflection point p is retained by the constraint equation (10), and it also passes step S164. Then, in step S166, the point p removed by the first camera 122 can be retrieved by fusing the results of the two cameras, as shown in equation (13).

[0112] CTP = fuse(CTP) li CTP ri (13)

[0113] However, there is also a situation with serious ambiguity, such as Figure 14 As shown. In this case, the ambiguity point p * Another ray is formed at the center of the second camera 124. Coincidentally, the second camera 124 transmits X-rays... The intensity is received from point p′. Therefore, the ambiguous point p * Information from the second camera 124 cannot be removed. It is worth noting that this situation rarely occurs, and this phenomenon disappears automatically when the laser moves. These severely ambiguous points form discrete external virtual contours, which can be removed through step S168. The calculation module 140 forms virtual contours using points acquired in the above steps when the laser moves. When discrete external virtual contours are formed, they are removed.

[0114] As analyzed above, severe ambiguities form discrete external virtual contours. Based on the continuity of the contours, the discrete external virtual contours can be removed using equation (14), such as... Figure 15 As shown.

[0115]

[0116] The parameter `radius` represents the points adjacent to the search radius, and the parameter `min`... pts This represents the minimum number of points within the search range. This means that in some embodiments, a point is removed when its neighboring points within the preset search range are fewer than a preset number.

[0117] According to another aspect of the present invention, the present invention also provides a method for three-dimensional reconstruction of a transparent object 20 using laser scanning. For example... Figure 16 As shown, the method for three-dimensional reconstruction of a transparent object 20 using laser scanning in this embodiment includes:

[0118] Step S220: When the reflection point is obtained by the first camera 122, the reflection point includes a first reflection point and a second reflection point. The first reflection point is closer to the reflection point of the laser on the galvanometer 114 than the second reflection point. The second reflection point is then removed.

[0119] Step S240: When the first reflection point is not captured by the second camera 124, the first reflection point is removed.

[0120] Step S260: When the second reflection point is acquired by the second camera 124, the second reflection point is retrieved.

[0121] For each row of the image, the number of the first reflection points is one. The number of the second reflection points can be one or more.

[0122] In some embodiments, in step S260, if the second camera 124 obtains two or more points, the second reflection point is closer to the laser reflection point on the galvanometer 114 than the other points.

[0123] refer to Figure 17 In some embodiments, the method further includes the following step after step S260:

[0124] Step S280: A virtual contour is formed by using the points acquired in the above steps when the laser moves; when a discrete external virtual contour is formed, the discrete external virtual contour is removed.

[0125] The refinement process reconstructs the outer surface of a transparent object 20 with an unknown interior. The refinement process extracts the front reflection points using optical geometric constraints. In step S220, spurious points can be removed using a single camera; in step S240, ambiguous points can be removed using joint constraints from two cameras; in step S260, lost front reflection outer surface points can be recovered through fusion; and in step S280, severely ambiguous points can be removed through contour continuity. Since severely ambiguous points are rare, step S280 can be omitted.

[0126] In some embodiments, step S280 includes the following step: when the number of adjacent points of a point within a preset search range is less than a preset number, the point is removed. The preset search range may be a preset search radius range. In other embodiments, the preset search range may also be a square range or a triangular range.

[0127] In some embodiments, Figure 16 and Figure 17 The method shown can be applied to, but is not limited to, electronic devices such as computers, smartphones, and personal digital assistants, to enable the 3D reconstruction system 10s to reconstruct the transparent object 20. In some embodiments, Figure 16 and 17 The method shown can be directly applied to the 3D reconstruction system 10.

[0128] refer to Figure 18 As shown, in some embodiments, the method further includes the following steps before step S220:

[0129] Step S212: Acquire image pairs using the first camera 122 and the second camera 124.

[0130] Step S214: Calculate the three-dimensional position of the point based on the image.

[0131] In step S214, in some embodiments, calibration parameters and triangulation may also be considered to calculate the three-dimensional position of the point. As described above in the embodiments, calibration parameters can be obtained by minimizing the objective function.

[0132] According to another aspect of the invention, the invention also provides an apparatus for three-dimensional reconstruction of a transparent object 20 using laser scanning. For example... Figure 19 As shown, the device for three-dimensional reconstruction of a transparent object 20 using laser scanning in this embodiment includes a memory 1001 and a processor 1002.

[0133] The processor 1002 is used to remove the second reflection point when a reflection point is acquired by the first camera 122, the reflection point including a first reflection point and a second reflection point, wherein the first reflection point is closer to the laser reflection point on the galvanometer 114 than the second reflection point. False points can be removed using a single camera.

[0134] The processor 1002 is also used to remove the first reflection point when the second camera 124 fails to acquire it. Ambiguous points can be removed through joint constraints between the two cameras.

[0135] The processor 1002 is also used to retrieve the second reflection point when the second camera 124 acquires the second reflection point. The lost front reflection outer surface point can be retrieved through fusion.

[0136] The processor 1002 is also used to acquire image pairs through the first camera 122 and the second camera 124, and calculate the three-dimensional position of the point based on the image pairs.

[0137] The processor 1002 is further configured to form a virtual contour using points acquired in the aforementioned steps during laser movement; and to remove the discrete external virtual contour when it is formed. Specifically, if a point has fewer than a preset number of adjacent points within a preset search range, that point is removed. Severely ambiguous points can be removed by maintaining contour continuity.

[0138] To verify the performance of the proposed method, experiments were conducted on system 10. The structured light generation module 110 includes a linear laser and a galvanometer 114 with uniaxial rotation capability. The linear laser scans the measurement surface by rotating the galvanometer mirror 114 to continuously set angles. Simultaneously, the image acquisition module 120 includes a first camera 122 with a first filter 1222 and a second camera 124 with a second filter 1242, which are synchronized to capture image pairs and transmit them to the computing module 140. The acquired images are then refined. Figures 20 to 23 The reconstruction of a plastic funnel and stacked water bottles is shown. Experimental results on real object 20 demonstrate that the method can successfully extract the front reflection point from candidate objects and recover the complex shapes of transparent and translucent objects 20.

[0139] The technical features in the above embodiments can be combined arbitrarily. For the sake of brevity, not all possible combinations of technical features in the embodiments are described. However, if the combination of technical features does not conflict with each other, the combination of technical features is considered to fall within the scope of this specification.

[0140] The above embodiments are merely detailed descriptions of several implementations of the present invention and should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make further changes and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of the present invention is determined by the scope of the appended claims.

Claims

1. A method for three-dimensional reconstruction of transparent objects using laser scanning, characterized in that, The method includes: When the reflection point is acquired by the first camera, the reflection point includes a first reflection point and a second reflection point. The first reflection point is closer to the laser reflection point on the galvanometer than the second reflection point. The second reflection point is then removed. When the first reflection point is not captured by the second camera, the first reflection point is removed; and When the second reflection point is obtained through the second camera, the second reflection point is retrieved; In this process, the laser light is reflected by a galvanometer onto a transparent object, and when the reflection point on the galvanometer... A laser is projected onto a surface point on the outer surface of a transparent object. When it rises, some light passes through the rays. The light is reflected directly into the first camera via diffuse reflection, while the remaining light is refracted into the transparent object, at a point... The light is reflected from the back surface and finally passes through the ray. The ray is captured by the first camera; the ray is determined by extracting feature laser points from the image of the first camera. and Candidate points were calculated based on triangulation: the first reflection point. Second reflection point ; For the second camera, the second reflection point The center of the second camera Another ray formed between them. Preserving the true points The image is then reprojected onto the plane of the second camera.

2. The method according to claim 1, characterized in that: Step: When a reflection point is acquired through the first camera, the reflection point includes a first reflection point and a second reflection point. The first reflection point is closer to the laser reflection point on the galvanometer than the second reflection point. Before removing the second reflection point, the method further includes: acquiring image pairs through the first camera and the second camera, and calculating the three-dimensional position of the point based on the image pairs; wherein the point is a candidate point calculated based on triangulation: the first reflection point. Second reflection point .

3. The method according to claim 2, characterized in that: The steps for calculating the three-dimensional position of a point based on an image pair include: calculating the three-dimensional position of the point based on the image pair, calibration parameters, and triangulation.

4. The method according to claim 3, characterized in that: The calibration parameters are obtained by minimizing the objective function.

5. The method according to claim 1, further comprising: When the first reflection point is not captured by the second camera, the first reflection point is removed, as it is an ambiguous point.

6. The method according to claim 5, further comprising: After removing the ambiguous points, when the second reflection point is obtained through the second camera, the second reflection point is retrieved. If the second camera obtains two or more points, the second reflection point is closer to the laser reflection point on the galvanometer than the other points.

7. The method according to claim 1, further comprising: A virtual contour is formed by using the points collected in the above steps as the laser moves; When a discrete external virtual contour is formed, the discrete external virtual contour is removed.

8. The method according to claim 7, characterized in that: When a discrete external virtual contour is formed, the step of removing the discrete external virtual contour includes: removing the point when the number of adjacent points of the point within a preset search range is less than a preset number; the point is any reflection point retained by the above steps.

9. The method according to claim 1, characterized in that: The step of retrieving the second reflection point when it is acquired by the second camera includes: if the second camera acquires two or more points, the second reflection point is closer to the laser reflection point on the galvanometer than the other points.

10. An apparatus for three-dimensional reconstruction of transparent objects using laser scanning, comprising: processor; and A non-transitory computer-readable medium connected to and storing thereon instructions for causing the processor to perform the following operations: When the reflection point is acquired by the first camera, the reflection point includes a first reflection point and a second reflection point. The first reflection point is closer to the laser reflection point on the galvanometer than the second reflection point. The second reflection point is then removed. If the first reflection point is not captured by the second camera, the first reflection point is removed. and When the second reflection point is obtained through the second camera, locate the second reflection point; In this process, the laser light is reflected by a galvanometer onto a transparent object, and when the reflection point on the galvanometer... A laser is projected onto a surface point on the outer surface of a transparent object. When it rises, some light passes through the rays. The light is reflected directly into the first camera via diffuse reflection, while the remaining light is refracted into the transparent object, at a point... The light is reflected from the back surface and finally passes through the ray. The ray is captured by the first camera; the ray is determined by extracting feature laser points from the image of the first camera. and Candidate points were calculated based on triangulation: the first reflection point. Second reflection point ; For the second camera, the second reflection point The center of the second camera Another ray formed between them. Preserving the true points The image is then reprojected onto the plane of the second camera.

11. The apparatus according to claim 10, characterized in that: In the step: when the reflection point is acquired by the first camera, the reflection point includes a first reflection point and a second reflection point, wherein the first reflection point is closer to the laser reflection point on the galvanometer than the second reflection point, before removing the second reflection point, the non-transitory computer-readable medium further stores thereon instructions for causing the processor to perform the following operations: Image pairs are acquired through the first camera and the second camera, and The three-dimensional position of the point is calculated based on the image; wherein the point is a candidate point calculated based on triangulation: the first reflection point. Second reflection point .

12. The apparatus according to claim 10, characterized in that: The non-transitory computer-readable medium further stores thereon instructions for causing the processor to perform the following operations: A virtual contour is formed by using the points acquired in the above steps as the laser moves; when a discrete external virtual contour is formed, the discrete external virtual contour is removed.

13. A system for three-dimensional reconstruction of transparent objects using laser scanning, comprising: A structured light generation module that emits a laser beam toward an object and allows the laser to scan the surface of the object being measured; An image acquisition module includes a first camera and a second camera, which collect feedback image pairs by capturing laser light reflected from the object; The control module is responsible for synchronizing the structured light generation module and the image acquisition module; and The calculation module acquires the image pairs from the image acquisition module and calculates the three-dimensional position of the points based on the image pairs. And a refinement process is performed to extract the front reflection point; wherein, the refinement process includes: When the reflection point is acquired by the first camera, the reflection point includes a first reflection point and a second reflection point. The first reflection point is closer to the laser reflection point on the galvanometer than the second reflection point. The second reflection point is then removed. When the first reflection point is not captured by the second camera, the first reflection point is removed; and When the second reflection point is acquired through the second camera, the second reflection point is retrieved. In this process, the laser light is reflected by a galvanometer onto a transparent object, and when the reflection point on the galvanometer... A laser is projected onto a surface point on the outer surface of a transparent object. When it rises, some light passes through the rays. The light is reflected directly into the first camera via diffuse reflection, while the remaining light is refracted into the transparent object, at a point... The light is reflected from the back surface and finally passes through the ray. The ray is captured by the first camera; the ray is determined by extracting feature laser points from the image of the first camera. and Candidate points were calculated based on triangulation: the first reflection point. Second reflection point ; For the second camera, the second reflection point The center of the second camera Another ray formed between them. Preserving the true points The image is then reprojected onto the plane of the second camera.

14. The system according to claim 13, characterized in that: The calculation module forms a virtual contour using the points acquired in the above steps when the laser moves; when a discrete external virtual contour is formed, the calculation module removes the discrete external virtual contour.

15. The system according to claim 14, characterized in that: When a discrete external virtual contour is formed, the step of the calculation module removing the discrete external virtual contour includes: when the number of adjacent points of the point within a preset search range is less than a preset number, the calculation module removes the point; the point is any reflection point retained by the calculation module.

16. The system according to claim 14, characterized in that: The structured light generation module includes a laser source and a galvanometer; the laser source emits laser light onto the galvanometer, and the galvanometer reflects the laser light onto the object.

17. The system according to claim 16, characterized in that: The galvanometer has a single-axis rotation capability, and the laser scans the surface being measured by rotating the galvanometer to a continuous preset angle.

18. The system according to claim 16, characterized in that: The laser beam can be in the shape of a dot, a line, or a curve.

19. The system according to claim 13, characterized in that: The first camera includes a first image sensor, a first optical lens, and a first filter, wherein the first optical lens is located between the first image sensor and the first filter; The second camera includes a second image sensor, a second optical lens, and a second filter, wherein the second optical lens is located between the second image sensor and the second filter; The wavelength of the laser is matched with the wavelengths transmitted by the first filter and the second filter.

20. The system according to claim 13, characterized in that: The control module is responsible for synchronizing the structured light generation module and the image acquisition module through pulse modulation.

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