Three-dimensional scanner, control method, laser, scanning system, equipment and medium

Abstract

The invention provides a three-dimensional scanner, a control method, a laser, a scanning system, equipment and a medium. The method comprises the following steps: acquiring current distance information between the three-dimensional scanner and a measured object; wherein the current distance information is used for representing the measured distance between the three-dimensional scanner and the measured object; and when the current distance information is greater than a specified distance threshold, adjusting a laser focus projected by the three-dimensional scanner to a target focus position corresponding to the current distance information. The position of the measured object is tracked in real time, and the laser focus projected by the three-dimensional scanner is adjusted to the target focus position corresponding to the current distance information under the condition that the position exceeds the specified distance threshold, so that continuous and stable high-precision data acquisition is realized in the whole measurement space.

Description

Technical Field

[0001] This application relates to the field of computer vision technology, specifically to a 3D scanner and control method, a laser and scanning system, equipment and media. Background Technology

[0002] Currently, with the widespread application of laser scanning technology in fields such as industrial component inspection, digital reconstruction of cultural relics, and robot vision guidance, its accuracy and efficiency are receiving increasing attention. However, to expand the scanning range, it is usually necessary to increase the number of lasers. Each laser needs to be focused independently according to its working distance, which not only increases the integration complexity of the system but also significantly increases hardware costs and debugging time. Summary of the Invention

[0003] This application provides a 3D scanner and control method, a laser and scanning system, equipment and medium through multiple embodiments, aiming to solve the problems of high difficulty in laser focusing and low scanning accuracy caused by the increase in laser line width.

[0004] In a first aspect, this application provides a control method for a 3D scanner, the method comprising: Obtain the current distance information between the 3D scanner and the object being measured; wherein, the current distance information is used to represent the measured distance between the 3D scanner and the object being measured; If the current distance information is greater than a specified distance threshold, the laser focus projected by the 3D scanner is adjusted to the target focus position corresponding to the current distance information.

[0005] Optionally, if the current distance information is greater than a specified distance threshold, adjusting the laser focus projected by the 3D scanner to the target focus position corresponding to the current distance information includes: The linewidth value of the laser line formed by the laser projected by the 3D scanner on the surface of the object under test is obtained; wherein, the linewidth value is used to represent the distance of the laser line in the width direction; Adjust the position of the laser focus so that the linewidth value falls within a specified range; wherein the linewidth value within the specified range is less than the linewidth value outside the specified range.

[0006] Optionally, if the current distance information is greater than a specified distance threshold, adjusting the laser focus projected by the 3D scanner to the target focus position corresponding to the current distance information further includes: If the current distance information is greater than a specified distance threshold, the target focusing distance is calculated based on the distance between the laser and the object being measured. Based on the target focusing distance, the focal length position of the 3D scanner is adjusted so that the current distance information is less than a specified distance threshold, wherein when the current distance information is less than the specified distance threshold, the line width value falls within a first specified value range. The laser focus is adjusted to move within the first specified value range so that the line width value falls within the second specified value range; wherein the second specified value range is located within the first specified value range, and the line width value within the second specified value range is less than the line width value outside the second specified value range.

[0007] Optionally, the 3D scanner includes at least one laser and at least two cameras. The laser includes a laser source, a focusing lens, and a drive motor. The laser source and the focusing lens are arranged sequentially along the light emission direction. The drive motor is disposed on the outer periphery of the focusing lens and is capable of driving the focusing lens to move along the optical axis. The method includes: The camera acquires the current distance information between the 3D scanner and the object being measured; wherein, the current distance information is used to represent the measured distance between the 3D scanner and the object being measured; If the current distance information is greater than a specified distance threshold, the focusing lens is adjusted by the drive motor so that the laser focus projected by the 3D scanner is aligned with the target focus position corresponding to the current distance information.

[0008] Optionally, the method includes: The camera acquires the linewidth value of the laser line formed by the laser from the laser on the surface of the object being measured. The focusing lens is driven by the drive motor to adjust the position of the laser focal point, so that the linewidth value falls within a specified range.

[0009] Secondly, one embodiment of this application also provides a laser, including: a laser source, a focusing lens, and a drive motor. The laser source and the focusing lens are arranged sequentially along the light emission direction. The drive motor is disposed on the outer periphery of the focusing lens and is capable of driving the focusing lens to move relative to the laser source.

[0010] Optionally, the drive motor includes a fixed base and a carrier. The fixed base is disposed inside the laser, and the carrier is movable along the optical axis and connected to the fixed base. The focusing lens is fixed on the carrier. The fixed base is provided with a first magnetic element, and the carrier is provided with a second magnetic element. The second magnetic element is configured to cooperate with the first magnetic element to drive the carrier to move relative to the fixed base.

[0011] Thirdly, one embodiment of this application also provides a three-dimensional scanner, including at least two cameras and a laser as described above, the laser being disposed between the two cameras.

[0012] Fourthly, one embodiment of this application also provides a laser scanning system, comprising: The acquisition module is used to acquire the current distance information between the 3D scanner and the object being measured; wherein, the current distance information is used to represent the measured distance between the 3D scanner and the object being measured; The adjustment module is used to adjust the laser focus projected by the 3D scanner to the target focus position corresponding to the current distance information when the current distance information is greater than a specified distance threshold.

[0013] Fifthly, one embodiment of this application also provides an electronic device, the electronic device including a memory and a processor, the memory storing at least one computer program, the at least one computer program being loaded and executed by the processor to implement the control method of the 3D scanner as described above.

[0014] Sixthly, one embodiment of this application also provides a computer-readable storage medium storing at least one computer program that, when executed by a processor, can implement the aforementioned control method for a 3D scanner.

[0015] In several embodiments provided in this application, by tracking the position of the object being measured in real time and adjusting the laser focus projected by the 3D scanner to the target focus position corresponding to the current distance information when the object exceeds a specified distance threshold, continuous and stable high-precision data acquisition is achieved throughout the entire measurement space. Attached Figure Description

[0016] Figure 1 This is a flowchart illustrating a control method for a 3D scanner provided as an embodiment of this specification.

[0017] Figure 2 This is a schematic diagram of the structure of a 3D scanner provided for one embodiment of this specification.

[0018] Figure 3 Another structural schematic diagram of a 3D scanner provided for one embodiment of this specification.

[0019] Figure 4 This is a partial structural diagram of a drive motor provided for one embodiment of this specification.

[0020] Figure 5This is another schematic flowchart illustrating a control method for a 3D scanner provided as an embodiment of this specification.

[0021] Figure 6 This is yet another flowchart illustrating a control method for a 3D scanner provided as an embodiment of this specification.

[0022] Figure 7 This is another schematic flowchart illustrating a control method for a 3D scanner provided as an embodiment of this specification.

[0023] Figure 8 This is another schematic flowchart illustrating a control method for a 3D scanner provided as an embodiment of this specification.

[0024] Figure 9 This is a schematic diagram of a laser scanning system provided for one embodiment of this specification.

[0025] Figure 10 This is a schematic diagram of an electronic device provided for one embodiment of this specification.

[0026] Explanation of reference numerals in the attached figures 100. 3D scanner; 10. Laser; 11. Laser source; 12. Focusing lens; 13. Drive motor; 131. Mount; 132. Carrier; 14. Grating sheet; 15. Powell prism; 20. Camera; 200. Laser scanning system; 201. Acquisition module; 202. Adjustment module; 300. Electronic device; 301. Memory; 302. Processor. Detailed Implementation

[0027] The technical solutions in the embodiments of this specification will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments.

[0028] In this specification, the accompanying drawings are not necessarily drawn to scale, and local features may be enlarged or reduced to show the details of the local features more clearly.

[0029] Unless otherwise stated, all technical and scientific terms used in this specification have the same meaning as commonly understood by one of ordinary skill in the art. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the scope of this specification. The term "and / or" as used in this specification includes any and all combinations of one or more of the associated listed items. The singular forms "a," "the," and "the" as used in this specification and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.

[0030] In the description of this specification, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of this specification, "a plurality of" means two or more, unless otherwise explicitly specified.

[0031] In the description of this specification, the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "height," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the purpose of simplifying the description in this specification and do not indicate that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. In other words, they should not be construed as limitations on this application.

[0032] In the description of this specification, unless otherwise expressly defined, the terms "installation," "connection," "joining," "fixing," "setting," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral part; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can also refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this specification according to the specific circumstances.

[0033] Currently, laser scanning technology is widely used in fields such as industrial inspection, digital reconstruction of cultural relics, and robot vision guidance, and its accuracy and efficiency are receiving increasing attention. A typical system usually uses a laser to project structured laser lines onto the surface of the object being measured, and then uses a binocular camera at a certain angle to the laser to capture the deformation of the laser lines in order to recover the three-dimensional shape of the object.

[0034] However, expanding the scanning range often requires increasing the number of lasers. Each laser needs to be independently focused according to its working distance, which not only increases the complexity of system integration but also significantly increases hardware costs and debugging time. Lasers cannot achieve stepless zoom; the linewidth outside the focusing distance will be wider than the linewidth at the focusing distance, thus affecting scanning accuracy. For example, for two lasers focusing at working distances of 1 meter and 2 meters respectively, the laser line will only be thinnest at 1 meter and 2 meters. Between 1 and 2 meters, the laser linewidth will increase, and the scanning accuracy will decrease accordingly. Since laser optical modules generally do not have continuous zoom capability, the laser line can only achieve optimal clarity and thinnest state at the preset focusing distance. In addition, while reducing the aperture increases the depth of field, the light utilization rate of the laser will also decrease. Due to the diffraction limit, the linewidth will not become thinner after the aperture is reduced to a certain value, and the depth of field will not increase further, only to a limited extent. Once the object is outside the depth of focus, the laser line will widen due to defocus, resulting in a decrease in the accuracy of laser center line extraction in the image, which in turn affects the three-dimensional measurement accuracy of the entire system.

[0035] Please see Figures 1 to 4 This application provides a control method for a 3D scanner 100, the method comprising: Step S10: Obtain the current distance information between the 3D scanner 100 and the object being measured; wherein, the current distance information is used to represent the measured distance between the 3D scanner 100 and the object being measured; Step S20: If the current distance information is greater than the specified distance threshold, adjust the laser focus projected by the 3D scanner 100 to the target focus position corresponding to the current distance information.

[0036] In this embodiment, by tracking the position of the object under test in real time, and adjusting the laser focus projected by the 3D scanner 100 to the target focus position corresponding to the current distance information when the object exceeds a specified distance threshold, continuous and stable high-precision data acquisition is achieved throughout the entire measurement space. By sensing the distance in real time and adaptively adjusting the focus, the laser line is ensured to remain at its finest and clearest state at different scanning distances. This allows the 3D scanner 100 to output high-precision data throughout the entire effective measurement space, achieving high-precision measurement.

[0037] In this embodiment, if the current distance information does not exceed the specified distance threshold, it indicates that the object being measured is still within the effective depth of field of the current focal point, and the drive motor will not be activated to adjust the position of the focusing lens. The laser maintains its existing optical state, and the focal position of the laser beam remains fixed.

[0038] It should be noted that, in this embodiment, the specified distance threshold is used to define the boundary of the effective depth of field corresponding to the current laser focus. The specified distance threshold value is directly related to the current focusing state of the laser. Specifically, when the 3D scanner initializes or completes the last focusing, its laser focus is set at a specific object distance (called the "current focusing distance"). Centered on this object distance, there exists an optically acceptable distance range that can keep the laser linewidth below an acceptable level; this range is its depth of field. The specified distance threshold can be set as the current focusing distance plus or minus half of the depth of field. That is, once the real-time measured current distance information exceeds this threshold range, it indicates that the measured object is outside the depth of field of the current focus, the laser linewidth will significantly widen, and the subsequent automatic focusing process will be triggered.

[0039] Furthermore, in this embodiment, the specific range of the specified distance threshold is not limited to meet different needs. The depth of field can be calculated through optical design parameters (such as focal length and aperture size) or obtained through calibration experiments. For example, for a scanning head with a set working distance of 500mm, its depth of field may be ±50mm, then the specified distance threshold can be set to 550mm and 450mm (or 540mm and 460mm with a certain margin).

[0040] Please see Figures 2 to 4 One embodiment of this application also provides a laser 10, including: a laser source 11, a focusing lens 12, and a drive motor 13. The laser source 11 and the focusing lens 12 are arranged sequentially along the light emission direction. The drive motor 13 is disposed on the outer periphery of the focusing lens 12 and can drive the focusing lens 12 to move relative to the laser source 11.

[0041] In this embodiment, the laser 10 integrates a drive motor 13, enabling the focusing lens 12 to move precisely relative to the laser source 11, thereby upgrading the traditional fixed-focus laser 10 into an optical module with continuous focusing capability. This allows the aforementioned control method to be implemented, thereby maintaining optimal laser line quality throughout the entire scanning range.

[0042] Please see Figures 2 to 4 The drive motor 13 includes a fixed base 131 and a carrier 132. The fixed base 131 is disposed inside the laser 10, and the carrier 132 is movable along the optical axis and connected to the fixed base 131. The focusing lens 12 is fixed on the carrier 132. A first magnetic element is disposed on the fixed base 131, and a second magnetic element is disposed on the carrier 132. The second magnetic element is configured to cooperate with the first magnetic element to drive the carrier 132 to move relative to the fixed base 131.

[0043] Thus, through the cooperation of the first magnetic component and the second magnetic component, the carrier 132 can be finely adjusted relative to the fixed base 131, thereby realizing the movement of the focusing lens 12 of the laser 10 relative to the light source, and thus realizing the automatic focusing of the laser 10.

[0044] In this embodiment, the focusing drive mechanism is built into the laser 10, forming an independent adjustable laser emitting unit. This facilitates the integration and assembly of the scanning system, as the laser 10 in this embodiment can be used as a standard component, significantly reducing the design difficulty of the 3D scanner 100.

[0045] In this embodiment, the specific types of the first and second magnetic components are not limited to meet different needs. For example, the first magnetic component can be a permanent magnet array, and the second magnetic component can be an energized coil; or the second magnetic component can be a permanent magnet array, and the first magnetic component can be an energized coil. By controlling the magnitude and direction of the current flowing through the energized coil, a controllable electromagnetic force is generated between it and the permanent magnet array, thereby driving the carrier 132 together with the focusing lens 12 to move precisely linearly relative to the fixed base 131.

[0046] Specifically, the aforementioned magnetic drive mechanism enables micron-level precision displacement of the carrier 132 and the focusing lens 12 in a non-contact manner. It eliminates mechanical friction and backlash, resulting in a long lifespan and high reliability. This allows the laser 10 to quickly and accurately adjust the focusing lens 12 to the target position according to control commands, thereby changing the focal point of the laser beam in real time and ultimately achieving efficient and stable autofocus. It provides an optimized actuator for high-precision, high-response autofocus. The drive motor 13 directly drives the lens, and its response speed, displacement accuracy, and stability directly determine the final performance of autofocus. Its compact structure facilitates the miniaturization of the laser 10. Magnetic drive mechanisms (such as VCMs) are typically flat and compact, allowing for highly efficient integration within the limited housing space of the laser 10 with almost no additional increase in its size. This is crucial for space-sensitive devices such as handheld scanners, ensuring enhanced functionality without sacrificing portability.

[0047] In this embodiment, the multi-line laser 10 contains a light source, a focusing lens 12, a grating 14, and a Powell prism 15. When focusing, the laser 10 adjusts the positions of the focusing lens 12 and the laser light source 11 to achieve focusing at different distances. Furthermore, a drive motor 13 is added to the focusing lens 12 to drive the lens to move back and forth. The camera 20 identifies the thickness of the laser line for automatic focusing, bringing the laser line width to its finest point. Additionally, in this embodiment, the type of drive motor 13 is not limited to meet different requirements. For example, the drive motor 13 is a voice coil motor (VCM motor). The principle of the VCM motor is that the current-carrying coil is subjected to the Ampere force in a constant magnetic field to produce linear motion. The lens is fixed inside the VCM motor by dispensing adhesive. Micron-level precision displacement control is achieved by changing the current. If a clear focus is to be achieved at a distance, a negative current is applied and the VCM motor drives the lens to move backward to achieve a clear focus at a distance. If a clear focus is to be achieved at a close distance, a positive current is applied and the VCM motor drives the lens to move forward to achieve a clear focus at a close distance.

[0048] Furthermore, the laser 10 includes a carrier 132, a coil, a magnet, a ring-shaped yoke, spring plates, and gaskets. The carrier 132 is used to fix the lens, and the coil is wound around the carrier 132. The magnet is fixed to the ring-shaped yoke at an angle; when energized, the magnet and coil generate magnetic force, pushing the carrier 132 carrying the lens in a linear motion. There is a spring plate on each of the upper and lower surfaces of the carrier 132 to limit the position of the carrier 132; the lower spring plate is the mover (energized), while the upper spring plate is not energized. In some VCM motors, gaskets can be placed on the upper and lower spring plates to protect the spring plates and prevent deformation.

[0049] Please see Figure 5 When the current distance information is greater than a specified distance threshold, adjusting the laser focus projected by the 3D scanner 100 to the target focus position corresponding to the current distance information includes: Step S21: Obtain the linewidth value of the laser line formed on the surface of the object being measured by the laser projected by the 3D scanner 100; wherein, the linewidth value is used to represent the distance of the laser line in the width direction; Step S22: Adjust the position of the laser focus so that the line width value falls within the specified range; wherein the line width value within the specified range is less than the line width value outside the specified range.

[0050] In this way, the actual imaging width (linewidth) of the laser line on the surface of the object being measured is acquired and analyzed in real time, and the imaging quality itself is used as a control signal, forming a closed-loop feedback system. By searching and locking with minimizing the linewidth as the direct objective, it can automatically compensate for lens processing errors, assembly deviations, temperature drift, and errors in distance measurement, thereby ensuring the stability and reliability of data acquisition quality on various complex workpieces.

[0051] In this embodiment, the laser line is stretched in one dimension perpendicular to the propagation direction, thus forming a narrow, high-brightness light band on the object surface. The linewidth of the laser line refers to the pixel width occupied by this laser line in the two-dimensional image captured by camera 20. It is usually measured in pixels. Ideally, when the laser beam is perfectly focused on the object surface, its energy is most concentrated, appearing as an extremely thin, sharp-edged, and uniformly bright line in the image captured by camera 20. At this point, the linewidth is the narrowest, possibly only 1-2 pixels wide. The autofocus method dynamically adjusts the linewidth to its narrowest point by moving the lens, regardless of the distance of the object, thereby ensuring the highest quality original image can be obtained at any distance, ultimately achieving continuous high-precision scanning throughout the entire workspace.

[0052] Specifically, the camera 20 of the 3D scanner 100 acquires an image of the laser line projected onto the surface of the object being measured, and an image processing algorithm is used to calculate the width of the laser line in the image, i.e., the linewidth value. This value, expressed in pixels, quantifies the lateral dimension of the laser line on the imaging plane. The drive motor 13 of the laser 10 is controlled to fine-tune the position of the focusing lens 12, thereby changing the focus of the laser beam. The goal of the adjustment is to make the calculated linewidth value fall within a preset specified value range (i.e., a specified value range). The specified value range is set as the linewidth interval corresponding to the optimal imaging quality; linewidth values ​​within this range are significantly smaller than linewidth values ​​outside this range. Through iterative fine-tuning, the laser focus is finally locked in the state of minimum and most stable linewidth value.

[0053] Please see Figure 6 If the current distance information is greater than a specified distance threshold, adjusting the laser focus projected by the 3D scanner 100 to the target focus position corresponding to the current distance information also includes: Step S23: If the current distance information is greater than the specified distance threshold, calculate the target focusing distance based on the distance between the laser 10 and the object being measured; Step S24: Adjust the focal length of the 3D scanner 100 according to the target focusing distance so that the current distance information is less than the specified distance threshold. When the current distance information is less than the specified distance threshold, the line width value falls within the first specified value range. Step S25: Adjust the laser focus to move within the first specified value range so that the line width value falls within the second specified value range; wherein the second specified value range is located within the first specified value range, and the line width value within the second specified value range is less than the line width value outside the second specified value range.

[0054] In this way, by pre-setting the laser scanning system 200 within a favorable initial specified range through coarse adjustment, the search range and uncertainty of closed-loop fine adjustment are greatly reduced. This not only simplifies the design of the fine adjustment algorithm and reduces the computational burden, but also avoids mechanical or optical interference that may be encountered during long-stroke searches, making the fine adjustment process faster and more robust. The overall system's anti-interference capability and focusing success rate are significantly improved. Subsequent fine adjustment only requires micro-movements of the drive motor 13 within a very small range. This reduces the number of large-scale precision drives, reduces mechanical wear and energy consumption, helps extend the service life of the drive motor 13 inside the laser 10, and improves the long-term reliability of the product.

[0055] In this embodiment, when the current distance information is greater than the specified distance threshold, the accuracy of the laser line can be guaranteed by adjusting the focal length twice, and the line width value can fall within the second specified value range.

[0056] Specifically, when the laser scanning system 200 determines that the current distance information exceeds a specified distance threshold, it first calculates the target focusing distance required to theoretically focus the laser beam at that distance, based on the distance information and the optical parameters of the laser 10, using a geometric optics model (e.g., the object-image conjugate formula). According to the calculated target focusing distance, the drive motor 13 (e.g., a VCM motor) is controlled to move the focusing lens 12 to the corresponding theoretical position. In this state, the laser linewidth has been significantly improved, and its value will fall within a preset, relatively loose first specified value range, marking the completion of coarse adjustment. Based on the good foundation of the first specified value range established by coarse adjustment, the laser scanning system 200 initiates precision focusing based on image feedback. The drive motor 13 is controlled to drive the focusing lens 12 to perform small-amplitude, reciprocating fine-tuning within this range, and the corresponding linewidth value changes are monitored in real time. The ultimate goal of the adjustment is to further converge and stabilize the linewidth value within a narrower and more optimal second specified value range. The second range is entirely within the first range, and its defined linewidth value is strictly smaller than the linewidth value of the non-second range portion within the first range, thus achieving linewidth minimization under the current conditions.

[0057] Please see Figure 7The 3D scanner 100 includes at least one laser 10 and at least two cameras 20. The laser 10 includes a laser source 11, a focusing lens 12 and a drive motor 13. The laser source 11 and the focusing lens 12 are arranged sequentially along the light emission direction. The drive motor 13 is located on the outer periphery of the focusing lens 12 and can drive the focusing lens 12 to move along the optical axis. The control methods for the 3D scanner 100 include: Step S30: Obtain the current distance information between the 3D scanner 100 and the object being measured through the camera 20; wherein, the current distance information is used to represent the measured distance between the 3D scanner 100 and the object being measured; Step S40: When the current distance information is greater than the specified distance threshold, the focusing lens 12 is adjusted by the drive motor 13 so that the laser focus projected by the 3D scanner 100 is at the target focus position corresponding to the current distance information.

[0058] Thus, by sensing the distance through the camera 20, the system controls the drive motor 13 to adjust the lens based on the distance information obtained by the camera 20. In this way, by integrating two cameras 20 and a laser 10 into the 3D scanner 100, and by directly integrating the drive motor 13 into the laser 10 and acting on the focusing lens 12, the complex external transmission mechanism is eliminated, and the shortest response path from control command to focus change is established.

[0059] In this embodiment, the binocular camera system 20 captures and processes images in real time based on the principle of triangulation, calculating and acquiring the current distance information between the 3D scanner 100 and the surface of the object being measured. This information provides core input for subsequent focusing decisions. The 3D scanner 100 compares the acquired current distance information with a preset specified distance threshold. If it determines that the current distance information is greater than the threshold (i.e., the object is outside the optimal depth of field range of the current focus), a control command is immediately generated to drive the drive motor 13 within the laser 10 to adjust the axial position of the focusing lens 12. This re-matches the focal position of the laser beam with the current distance of the object being measured, i.e., moves it to the target focal position corresponding to the distance information.

[0060] Please see Figure 8 The control methods for the 3D scanner 100 include: Step S50: The camera 20 acquires the linewidth value of the laser line formed by the laser 10 on the surface of the object being measured. Step S60: Drive the focusing lens 12 by the drive motor 13 to adjust the position of the laser focus so that the line width value falls within the specified range.

[0061] In this way, the line width value is acquired by the camera 20, and then the motor 13 is driven to drive the focusing lens 12 to adjust the position of the laser focus so that the line width value falls within the specified range, thereby ensuring the high-precision detection of the 3D scanner 100.

[0062] In this embodiment, the 3D scanner 100 no longer relies on indirect calculations from distance measurements, but instead uses the final image quality (linewidth), which directly affects the accuracy of 3D reconstruction, as the control target. This allows the focusing process to directly respond to and correct all the combined factors that cause image blurring, including optical defocus, environmental interference, and differences in object surface characteristics.

[0063] Optionally, the determination of the specified distance threshold satisfies the following object-image conjugate relationship: 1 / F = 1 / u + 1 / v; Where F is the focal length of the focusing lens 12, u is the object distance of the laser 10, and v is the image distance of the laser 10.

[0064] In this way, the position that the focusing lens 12 needs to be adjusted can be calculated according to the object-image conjugate formula.

[0065] In this embodiment, the binocular camera 20 can identify the height of the scanning system relative to the scanned object based on the triangulation principle. If the scanning distance exceeds the set range, the drive motor 13 starts to drive the focusing lens 12 to move to the theoretically calculated position. For example, if the current scanning range is 300mm ± 20mm, and it exceeds 320mm, the drive motor 13 will drive the focusing lens to the lens position corresponding to the scanning distance. Furthermore, the position that the focusing lens 12 needs to be adjusted can be calculated based on the object-image conjugate formula. For example, if the focal length of the focusing lens 12 is 8mm, and the scanning distance changes from 300mm to 500mm, the focusing lens 12 moves 0.049mm towards the light source.

[0066] Thirdly, one embodiment of this application also provides a 3D scanner 100, including at least two cameras 20 and a laser 10 as described above, the laser 10 being disposed between the two cameras 20.

[0067] In this embodiment, when the focusing lens 12 reaches the designated position, it will make fine adjustments based on the thickness of the laser line, adjusting it to the thinnest point of the laser line in the image captured by the camera 20. The thickness of the laser line is determined based on the number of pixels occupied by the line width. When the focusing lens 12 reaches the designated position, it makes fine adjustments back and forth, and the number of pixels occupied by the laser line will go through a process of increasing and then decreasing, until finally the focusing lens 12 stops at the position with the fewest laser line pixels, reducing autofocus time.

[0068] Please see Figure 9 One embodiment of this application also provides a laser scanning system 200, comprising: The acquisition module 201 is used to acquire the current distance information between the 3D scanner 100 and the object being measured; wherein, the current distance information is used to represent the measured distance between the 3D scanner 100 and the object being measured. The adjustment module 202 is used to adjust the laser focus projected by the 3D scanner 100 to the target focus position corresponding to the current distance information when the current distance information is greater than a specified distance threshold.

[0069] In this embodiment, the laser 10 emits multiple or single laser lines to scan the object under test. The laser line data is then collected by the binocular camera 20 for calculation. The thinner the laser line, the higher the scanning resolution, making it easier to scan small objects and thus increasing scanning accuracy. Therefore, if the laser line remains as thin as possible at different scanning distances, the scanning accuracy can reach its optimal level throughout the entire scanning range. In this embodiment, a drive motor 13 is added to the focusing lens 12 to drive the focusing lens 12 to move, thereby achieving a zoom effect. The drive motor 13 can be a VCM motor or a gear motor, or any device that can drive the lens to move; no specific limitation is made here. The 3D scanner 100 automatically zooms by recognizing the thickness of the laser line in the image. The focusing logic is that after exceeding the depth of field range, the drive motor 13 starts driving the lens to focus. The lens position is first calculated, and then fine-tuned back and forth until the laser line is as thin as possible, reducing the autofocus time.

[0070] Please see Figure 10 One embodiment of this application also provides an electronic device 300, which includes a memory 301 and a processor 302. The memory 301 stores at least one computer program, which is loaded and executed by the processor 302 to implement the control method of the 3D scanner 100 as described above.

[0071] One embodiment of this application also provides a computer-readable storage medium storing at least one computer program, which, when executed by processor 302, can implement the control method of the 3D scanner 100 as described above.

[0072] In several embodiments provided in this application, by tracking the position of the object being measured in real time and adjusting the laser focus projected by the 3D scanner 100 to the target focus position corresponding to the current distance information when the object exceeds a specified distance threshold, continuous and stable high-precision data acquisition is achieved throughout the entire measurement space.

[0073] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0074] The functions and effects of this embodiment can be explained by referring to the foregoing implementation methods, and will not be repeated here.

[0075] It is understood that in the various embodiments of this specification, the sequence number of each process does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this specification.

[0076] It is understood that the various implementation methods described in this specification can be implemented individually or in combination, and the embodiments in this specification are not limited in this respect.

[0077] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the aforementioned method implementations, and will not be repeated here.

[0078] The above are merely specific embodiments of this specification, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this specification should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A control method for a 3D scanner, characterized in that, The method includes: Obtain the current distance information between the 3D scanner and the object being measured; wherein, the current distance information is used to represent the measured distance between the 3D scanner and the object being measured; If the current distance information is greater than a specified distance threshold, the laser focus projected by the 3D scanner is adjusted to the target focus position corresponding to the current distance information.

2. The control method for a three-dimensional scanner according to claim 1, characterized in that, When the current distance information is greater than a specified distance threshold, adjusting the laser focus projected by the 3D scanner to the target focus position corresponding to the current distance information includes: The linewidth value of the laser line formed by the laser projected by the 3D scanner on the surface of the object under test is obtained; wherein, the linewidth value is used to represent the distance of the laser line in the width direction; Adjust the position of the laser focus so that the linewidth value falls within a specified range; wherein the linewidth value within the specified range is less than the linewidth value outside the specified range.

3. The control method for a three-dimensional scanner according to claim 1, characterized in that, When the current distance information is greater than a specified distance threshold, adjusting the laser focus projected by the 3D scanner to the target focus position corresponding to the current distance information further includes: If the current distance information is greater than a specified distance threshold, the target focusing distance is calculated based on the distance between the laser and the object being measured. Based on the target focusing distance, the focal length position of the 3D scanner is adjusted so that the current distance information is less than a specified distance threshold, wherein when the current distance information is less than the specified distance threshold, the line width value falls within a first specified value range. The laser focus is adjusted to move within the first specified value range so that the line width value falls within the second specified value range; wherein the second specified value range is located within the first specified value range, and the line width value within the second specified value range is less than the line width value outside the second specified value range.

4. The control method for a three-dimensional scanner according to any one of claims 2 or 3, characterized in that, The 3D scanner includes at least one laser and at least two cameras. The laser includes a laser source, a focusing lens, and a drive motor. The laser source and the focusing lens are arranged sequentially along the light emission direction. The drive motor is disposed on the outer periphery of the focusing lens and is capable of driving the focusing lens to move along the optical axis. The method includes: The camera acquires the current distance information between the 3D scanner and the object being measured; wherein, the current distance information is used to represent the measured distance between the 3D scanner and the object being measured; If the current distance information is greater than a specified distance threshold, the focusing lens is adjusted by the drive motor so that the laser focus projected by the 3D scanner is aligned with the target focus position corresponding to the current distance information.

5. The control method for a three-dimensional scanner according to claim 4, characterized in that, The method includes: The camera acquires the linewidth value of the laser line formed by the laser from the laser on the surface of the object being measured. The focusing lens is driven by the drive motor to adjust the position of the laser focal point, so that the linewidth value falls within a specified range.

6. A laser, characterized in that, include: The laser source, the focusing lens, and the drive motor are arranged sequentially along the light emission direction. The drive motor is located on the outer periphery of the focusing lens and can drive the focusing lens to move relative to the laser source.

7. The laser according to claim 6, characterized in that, The drive motor includes a fixed base and a carrier. The fixed base is disposed inside the laser, and the carrier is movable along the optical axis and connected to the fixed base. The focusing lens is fixed on the carrier. The fixed base is provided with a first magnetic element, and the carrier is provided with a second magnetic element. The second magnetic element is configured to cooperate with the first magnetic element to drive the carrier to move relative to the fixed base.

8. A three-dimensional scanner, characterized in that, It includes at least two cameras and a laser as described in any one of claims 6 or 7, the laser being disposed between the two cameras.

9. A laser scanning system, characterized in that, include: The acquisition module is used to acquire the current distance information between the 3D scanner and the object being measured; wherein, the current distance information is used to represent the measured distance between the 3D scanner and the object being measured; The adjustment module is used to adjust the laser focus projected by the 3D scanner to the target focus position corresponding to the current distance information when the current distance information is greater than a specified distance threshold.

10. An electronic device, characterized in that, The electronic device includes a memory and a processor. The memory stores at least one computer program, which is loaded and executed by the processor to implement the control method of the three-dimensional scanner as described in any one of claims 1 to 5.

11. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores at least one computer program, which, when executed by a processor, enables the control method of the three-dimensional scanner as described in any one of claims 1 to 5.

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