Laser scanning device, security system and scanning control method

Abstract

The application discloses a laser scanning device, a security system and a scanning control method. In the laser scanning device, a micro-electro-mechanical device is arranged correspondingly with a one-dimensional scanning galvanometer, so that laser light is reflected between the micro-electro-mechanical device and the one-dimensional scanning galvanometer; the one-dimensional scanning galvanometer can rotate the laser light emitted from the one-dimensional scanning galvanometer in a direction around a first direction; a rotating part can rotate the laser light emitted from the one-dimensional scanning galvanometer in a direction around a second direction; the second direction is perpendicular to the first direction; in a first working mode, the micro-electro-mechanical device reflects the laser light, the one-dimensional scanning galvanometer scans a scanned object at a first resolution, and when the scanned object meets the first resolution, the working mode is switched to a second working mode; in the second working mode, the micro-electro-mechanical device scans the scanned object at a second resolution higher than the first resolution. The laser scanning device has relatively small assembly and adjustment difficulty and relatively low cost, and effectively expands the field of view range of a digital micro-mirror.

Description

Technical Field

[0001] This application relates to the field of lidar technology, and in particular to a laser scanning device, a security system, and a scanning control method. Background Technology

[0002] LiDAR is a new type of sensor that can be applied in fields such as security and driver assistance. It allows for the detection of object distribution within a detection area. Currently, in solid-state LiDAR systems, due to the small field of view of digital micromirrors, multiple laser transceivers are typically arranged sequentially. By multiplexing the angles at which the laser beams incident on the galvanometers of these transceivers differ, the digital micromirrors are reused to expand the detection field of view. However, having multiple laser transceivers increases the difficulty of assembling and calibrating the solid-state LiDAR system, prevents the digital micromirrors from operating at their optimal incident angle, and results in relatively high costs. Summary of the Invention

[0003] This application discloses a laser scanning device, a security system, and a scanning control method, which are relatively easy to assemble and adjust, and have relatively low cost.

[0004] To solve the above problems, this application adopts the following technical solution:

[0005] In a first aspect, embodiments of this application provide a laser scanning device, comprising a laser transceiver assembly, a rotating part, a one-dimensional scanning galvanometer, a base, and microelectromechanical devices (MEMS). The rotating part and the MEMS are both mounted on the base, and the one-dimensional scanning galvanometer is correspondingly disposed with respect to the MEMS, such that laser light is reflected between the MEMS and the one-dimensional scanning galvanometer. The one-dimensional scanning galvanometer is used to reflect laser light to a scanned object and to reflect echo signals reflected back from the scanned object to the MEMS. The MEMS is used to reflect laser light emitted from the laser transceiver assembly to the scanned object and to reflect the echo signals back to the laser transceiver assembly. The one-dimensional scanning galvanometer is movably mounted on the base, and the laser light emitted from the one-dimensional scanning galvanometer rotates in a direction about a first direction. The rotating part is used to rotate the laser light emitted from the one-dimensional scanning galvanometer in a direction about a second direction, wherein the first direction and the second direction are perpendicular to each other.

[0006] The laser scanning device has a first working mode and a second working mode. In the first working mode, the one-dimensional scanning galvanometer moves relative to the base, the microelectromechanical device (MEMS) is used to reflect laser light, the one-dimensional scanning galvanometer scans the object being scanned at a first resolution, and when the object being scanned meets the first resolution, the laser scanning device switches to the second working mode. In the second working mode, the one-dimensional scanning galvanometer is stationary relative to the base, the MEMS is operational, and is used to scan the object being scanned at a second resolution, which is higher than the first resolution.

[0007] Secondly, embodiments of this application provide a security system that includes the aforementioned laser scanning device.

[0008] Thirdly, embodiments of this application provide a scanning control method applied to the aforementioned laser scanning device, the scanning control method comprising:

[0009] Control the one-dimensional scanning galvanometer to scan the field of view at a first resolution;

[0010] When the field of view includes a scanned object that satisfies the first resolution, the microelectromechanical device is controlled to scan the scanned object at a second resolution.

[0011] The technical solution adopted in this application can achieve the following beneficial effects:

[0012] This application discloses a laser scanning device, which includes a laser transceiver assembly, a rotating part, a one-dimensional scanning galvanometer, a base, and microelectromechanical devices (MEMS). The MEMS cooperates with the one-dimensional scanning galvanometer so that the laser emitted by the laser transceiver assembly can be reflected by the MEMS and the one-dimensional scanning galvanometer to the object being scanned. Correspondingly, the echo signal reflected by the object being scanned can also be reflected by the one-dimensional scanning galvanometer and the MEMS back to the laser transceiver assembly.

[0013] A one-dimensional scanning galvanometer is movably mounted on a base, and the laser beam emitted from the galvanometer can rotate around a first direction. A rotating part allows the laser beam emitted from the galvanometer to rotate around a second direction. The first and second directions are perpendicular to each other, thereby changing the propagation path of the laser beam directed at the scanned object, and thus altering the landing point of the laser beam on the scanned object. Taking the case where the rotating part of the laser scanning device operates using a stepper motor as an example, the galvanometer itself can complete a longitudinal (i.e., the direction of the second direction) scan of the corresponding position in the field of view. Simultaneously, since the rotation axis of the rotating part is perpendicular to the rotation axis of the galvanometer, after the galvanometer completes the aforementioned longitudinal scan of a certain position in the field of view, the rotating part can drive the galvanometer to move, causing the laser beam reflected by the galvanometer to be directed towards another position in the field of view adjacent to the aforementioned position in the direction of the second direction. Then, under the action of the galvanometer, a longitudinal scan of the aforementioned other position can continue.

[0014] Furthermore, the aforementioned laser scanning device has a first working mode and a second working mode. The scanning using a one-dimensional scanning galvanometer is the first working mode. In this mode, the one-dimensional scanning galvanometer moves relative to the base, and the microelectromechanical device (MEMS) provides the reflection function. The one-dimensional scanning galvanometer scans the object at a first resolution. When the object meets the first resolution, the laser scanning device can switch to the second working mode. In the second working mode, the one-dimensional scanning galvanometer is stationary relative to the base, and the MEMS provides the scanning function, performing a more refined scanning of the object at a second resolution greater than the first resolution. In this mode, the working field of view of the MEMS can be greatly expanded. Under the premise of fully utilizing the advantages of the MEMS's precision and high-speed scanning, its working field of view is effectively expanded.

[0015] In addition, as mentioned above, the laser scanning device is equipped with only one set of laser transceiver components. This makes the assembly and adjustment of the laser transceiver components and the one-dimensional scanning galvanometer relatively easy. Furthermore, since the same laser transceiver components are used, the laser light from the laser transceiver module can be incident on the one-dimensional scanning galvanometer and microelectromechanical devices at the optimal angle, ensuring good scanning performance of the system. Attached Figure Description

[0016] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:

[0017] Figure 1 This is a schematic diagram of the structure of a laser scanning device disclosed in an embodiment of this application;

[0018] Figure 2 This is another structural schematic diagram of the laser scanning device disclosed in the embodiments of this application;

[0019] Figure 3 This is another structural schematic diagram of the laser scanning device disclosed in the embodiments of this application;

[0020] Figure 4 This is a schematic diagram of a portion of the structure of the laser scanning device disclosed in the embodiments of this application;

[0021] Figure 5 This is a flowchart of the scanning control method disclosed in the embodiments of this application.

[0022] Explanation of reference numerals in the attached figures:

[0023] 110 - Laser emitter, 120 - Laser detector

[0024] 210 - Rotating part, 230 - One-dimensional scanning galvanometer, 240 - Reflecting device

[0025] 300-base,

[0026] 400-Microelectromechanical Devices (MEMS)

[0027] 510 - Collimation device, 520 - Converging device. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below in conjunction with specific embodiments and corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0029] The technical solutions disclosed in the various embodiments of this application are described in detail below with reference to the accompanying drawings.

[0030] like Figures 1-3As shown in the illustration, this application discloses a laser scanning device, which includes a laser transceiver assembly, a rotating part 210, a one-dimensional scanning galvanometer 230, a base 300, and a microelectromechanical device (MEMS) 400. The base 300 serves as a mounting foundation, and the laser transceiver assembly, rotating part 210, one-dimensional scanning galvanometer 230, and MEMS 400 can all be directly or indirectly mounted on the base 300, thereby forming a complete and independent mechanism for the laser scanning device. More specifically, the base 300 may include multiple parts, such as an upper base and a lower base. In this case, the laser transceiver assembly and MEMS can be mounted on the lower base, while at least one of the rotating part 210 and the one-dimensional scanning galvanometer 230 can be mounted on the upper base. Of course, the structure of the base 300 is not limited. For example, the base 300 can be an irregular structure. In this case, the laser transceiver assembly, the rotating part 210, the one-dimensional scanning galvanometer 230, and the microelectromechanical device 400 can be installed at different positions on the base 300 to ensure that the laser beam can be reflected between the one-dimensional scanning galvanometer 230 and the microelectromechanical device 400.

[0031] The laser transceiver unit has the ability to emit and receive laser light. It can emit laser light and receive echo signals directed at it. Specifically, the laser transceiver unit can be an integrated laser transceiver, which can be fixed to the base 300 using screws or other connectors. The one-dimensional scanning galvanometer 230 can reflect laser light to the scanned object and reflect the echo signals reflected from the scanned object to the microelectromechanical device 400. The microelectromechanical device 400 can reflect the laser light emitted by the laser transceiver unit to the scanned object and reflect the echo signals back to the laser transceiver unit. Specifically, by setting the positions and orientations of the laser transceiver assembly, the one-dimensional scanning galvanometer 230, and the microelectromechanical device (MEMS) 400, the laser emitted from the laser transceiver assembly can be directed to the one-dimensional scanning galvanometer 230 via the MEMS 400. The one-dimensional scanning galvanometer 230 can reflect the laser light onto the object being scanned. Correspondingly, after the laser light irradiates the object being scanned and is reflected, the reflected echo signal can also be reflected back to the laser transceiver assembly via the one-dimensional scanning galvanometer 230 and the MEMS 400, thereby forming a complete laser optical path. This enables the laser scanning device to scan the object and obtain parameters such as the shape, size, or motion information of the scanned object.

[0032] Both the rotating part 210 and the microelectromechanical device (MEMS) 400 are mounted on the base 300, and the one-dimensional scanning galvanometer 230 is correspondingly arranged with the MEMS 400, allowing laser light to be reflected between the MEMS 400 and the one-dimensional scanning galvanometer 230. Specifically, by designing the mounting positions of the MEMS 400 and the one-dimensional scanning galvanometer 230, such as having their light-receiving surfaces facing each other but not parallel, laser light can be reflected between them. Optionally, both the MEMS 400 and the rotating part 210 can be directly mounted on the base 300, and the one-dimensional scanning galvanometer 230 can be directly mounted on the base 300. Alternatively, the one-dimensional scanning galvanometer 230 can also be indirectly mounted on the base 300 via the rotating part 210, ensuring that the one-dimensional scanning galvanometer 230 corresponds to the MEMS 400.

[0033] The one-dimensional scanning galvanometer 230 is movably mounted on the base 300. Specifically, as described above, regardless of whether the one-dimensional scanning galvanometer 230 is directly or indirectly mounted on the base 300, it can be ensured that the one-dimensional scanning galvanometer 230 can move relative to the base 300. The one-dimensional scanning galvanometer 230 can cause the laser light emitted from the one-dimensional scanning galvanometer 230 to rotate in a direction around a first direction. That is, the one-dimensional scanning galvanometer 230 can change the propagation trajectory of the laser light reflected from the one-dimensional scanning galvanometer 230 through its own rotation. Specifically, the one-dimensional scanning galvanometer 230 may include a driving source and a reflector. The reflector is mounted on the driving source, which can be directly or indirectly mounted on the base 300. When the driving source is activated, it can drive the reflector to rotate relative to the driving source, and the axis of their relative rotation is the first direction.

[0034] The rotating part 210 can also provide a rotational drive to drive the component connected to the rotating part 210 to rotate in a direction around the second direction. As described above, the one-dimensional scanning galvanometer 230 can rotate the laser light emitted from the one-dimensional scanning galvanometer 230 in a direction around the first direction. Correspondingly, the rotating part 210 can rotate the laser light emitted from the one-dimensional scanning galvanometer 230 in a direction around the second direction, and the first direction and the second direction are perpendicular to each other, so as to change the propagation path of the laser light beam directed towards the scanned object.

[0035] Specifically, the rotating part 210 is mounted on the base 300, and the one-dimensional scanning galvanometer 230 can be mounted on the rotating part 210. Alternatively, if the one-dimensional scanning galvanometer 230 is directly mounted on the base 300, a reflective device can be additionally installed on the rotating part 210 so that the rotation of the rotating part 210 can act on the light reflected by the one-dimensional scanning galvanometer 230, thereby changing the propagation path of the laser light directed toward the scanned object.

[0036] Taking the one-dimensional scanning galvanometer 230 movably mounted on the rotating part 210 as an example, the extension direction of the rotation axis of the rotating part 210 is the second direction. The one-dimensional scanning galvanometer 230 is mounted on the drive shaft of the rotating part 210, so that when the rotating part 210 is working, the one-dimensional scanning galvanometer 230 can rotate around the drive shaft of the rotating part 210, which allows the orientation of the one-dimensional scanning galvanometer 230 to change with the movement of the rotating part 210.

[0037] Furthermore, the one-dimensional scanning galvanometer 230 itself can also move relative to the base 300. As described above, the rotating part 210 can drive the one-dimensional scanning galvanometer 230 to rotate around the driving shaft of the rotating part 210. With the extension direction of the rotation shaft of the rotating part 210, i.e. the second direction, as the vertical direction, the one-dimensional scanning galvanometer 230 can also make the laser light emitted from the one-dimensional scanning galvanometer 230 rotate in the direction around the first direction. Thus, under the combined action of the rotating part 210 and the one-dimensional scanning galvanometer 230, the entire laser scanning device can perform both horizontal and vertical scanning.

[0038] Specifically, the rotating part 210 can be a rotary motor, or more specifically, a stepper motor or a continuous motor. Optionally, the rotating part 210 can be connected to the one-dimensional scanning galvanometer 230. Alternatively, if the one-dimensional scanning galvanometer 230 is directly mounted on the base 300, a reflective device can be additionally configured for the laser scanning equipment, and the reflective device can be mounted on the rotating part 210. Both of these methods can change the propagation path of the laser light beam directed towards the scanned object. It should be noted that during the process of adjusting the propagation path of the laser light beam directed towards the scanned object through the rotating part 210 and the one-dimensional scanning galvanometer 230, the rotation range of the rotating part 210 and the one-dimensional scanning galvanometer 230 needs to be limited to ensure that the one-dimensional scanning galvanometer 230 is always on the propagation path of the laser light beam.

[0039] The microelectromechanical device (MEMS) 400 possesses the ability to reflect light. Specifically, the MEMS 400 can be a digital micromirror device, a microelectromechanical galvanometer, or a deformable mirror. Of course, the MEMS 400 can also include a liquid crystal device, an optical waveguide device, or other beam control devices. Its function is to change the direction or phase of light. All devices that can provide this function can be used as MEMS in this application to perform fine scanning of the object within the field of view. Taking the MEMS 400 as a digital micromirror device as an example, by utilizing the controllable characteristics and high-speed flipping frequency of the pixel-level lenses on the MEMS 400, active scanning imaging of the target area on the scanned object can be achieved by modulating the pixel-level lenses on the MEMS 400. That is, by using the MEMS 400, more precise scanning imaging of the object within the field of view of the laser scanning device can be performed, further improving the scanning accuracy of the scanned object. Simultaneously, by adjusting the laser emission parameters of the MEMS 400 and the laser transceiver assembly, the MEMS 400 can achieve scanning imaging at different resolutions.

[0040] In this embodiment, the one-dimensional scanning galvanometer 230 can be used alone to quickly scan the object within the field of view. During this process, a relatively fine target parameter can be set first, allowing the laser scanning device to perform a "coarse scan" to shorten the time required for the laser scanning device to completely scan the entire field of view. Of course, in the above process, for objects whose parameters are similar to the target parameters, the laser scanning device can determine and record the parameter information of their specific position within the field of view. Then, under the action of the rotating part 210 and the one-dimensional scanning galvanometer 230, the microelectromechanical device 400 can be aligned with the object to be scanned for a more refined scanning process.

[0041] Based on the above, the laser scanning device has a first working mode and a second working mode. In the first working mode, the one-dimensional scanning galvanometer 230 moves relative to the base 300. That is, the one-dimensional scanning galvanometer 230 performs a longitudinal scanning process under its own drive. During this process, the microelectromechanical device 400 does not move itself, but only acts as a reflective device to reflect laser light. It provides the function of reflecting laser light during the working process of the one-dimensional scanning galvanometer 230. The one-dimensional scanning galvanometer 230 can scan the object being scanned at a first resolution. Furthermore, when the object being scanned meets the first resolution, the laser scanning device switches to the second working mode to perform a more detailed scan of the object that meets the first resolution.

[0042] In the second working mode, the one-dimensional scanning galvanometer 230 is stationary relative to the base 300, that is, the one-dimensional scanning galvanometer 230 no longer rotates to perform longitudinal scanning. In the second working mode, the microelectromechanical device 400 works to generate corresponding actions through its own lens, scans the object being scanned at a second resolution, and forms an image of the corresponding resolution. The second resolution is higher than the first resolution, ensuring that the microelectromechanical device 400 can provide a more accurate scanning process.

[0043] This application discloses a laser scanning device, which includes a laser transceiver assembly, a rotating part 210, a one-dimensional scanning galvanometer 230, a base 300, and a microelectromechanical device (MEMS) 400. The MEMS 400 cooperates with the one-dimensional scanning galvanometer 230 so that the laser emitted by the laser transceiver assembly can be reflected by the MEMS 400 and the one-dimensional scanning galvanometer 230 onto the object being scanned. Correspondingly, the echo signal reflected from the object being scanned can also be reflected by the one-dimensional scanning galvanometer 230 and the MEMS 400 back to the laser transceiver assembly.

[0044] The one-dimensional scanning galvanometer 230 is movably mounted on the base 300, and the laser light emitted from the one-dimensional scanning galvanometer 230 can rotate in a direction around the first direction. The rotating part 210 can make the laser light emitted from the one-dimensional scanning galvanometer 230 rotate in a direction around the second direction. The first direction and the second direction are perpendicular to each other, thereby changing the propagation path of the laser light beam directed towards the scanned object, and thus changing the landing position of the laser light beam on the scanned object. Taking the case where the rotating part 210 of the laser scanning device operates in the working mode of a stepper motor as an example, under the action of the one-dimensional scanning galvanometer 230 itself, it can complete the longitudinal (i.e., the direction in which the second direction is located) scanning process of the corresponding position in the field of view; at the same time, since the rotation axis of the rotating part 210 is perpendicular to the rotation axis of the one-dimensional scanning galvanometer 230, after the one-dimensional scanning galvanometer 230 completes the aforementioned longitudinal scanning process of a certain position in the field of view, under the action of the rotating part 210, it can drive the one-dimensional scanning galvanometer 230 to move, so that the laser light reflected by the one-dimensional scanning galvanometer 230 is directed to another position in the field of view that is adjacent to the aforementioned position in the direction surrounding the second direction. Then, under the action of the one-dimensional scanning galvanometer 230, the longitudinal scanning process of the aforementioned other position can continue to be completed.

[0045] Furthermore, the laser scanning device described above has a first working mode and a second working mode. The scanning using the one-dimensional scanning galvanometer 230 is the first working mode. In this working mode, the one-dimensional scanning galvanometer 230 moves relative to the base 300, and the microelectromechanical device 400 provides a reflection function. The one-dimensional scanning galvanometer 230 scans the object at a first resolution. When the object meets the first resolution, the laser scanning device can switch to the second working mode. In the second working mode, the one-dimensional scanning galvanometer 230 is relatively stationary with respect to the base 300, and the microelectromechanical device 400 provides a scanning function, performing a more refined scanning of the object at a second resolution greater than the first resolution. In this working mode, the working field of view of the microelectromechanical device 400 can be greatly expanded. Under the premise of fully utilizing the advantages of the microelectromechanical device 400's fineness and high-speed scanning, its working field of view can be effectively expanded.

[0046] In addition, as mentioned above, the laser scanning device is equipped with only one set of laser transceiver components, which makes the assembly and adjustment between the laser transceiver components and the one-dimensional scanning galvanometer 230 in the laser scanning device relatively easy. Furthermore, since the same laser transceiver components are used, the laser light from the laser transceiver module can be incident on the one-dimensional scanning galvanometer 230 and the microelectromechanical device 400 at the optimal angle, ensuring good scanning performance of the system.

[0047] Of course, the rotating part 210 can also be driven by a continuous motor. In this case, the pattern of the scanning trajectory of the laser scanning device within the field of view is approximately a uniformly distributed curve.

[0048] In laser scanning equipment, to ensure relatively high scanning accuracy, the laser emitted by the laser transceiver component can be a parallel laser beam. In another embodiment of this application, the laser transceiver component includes a laser emitter 110, which can specifically be a single-point laser. In this case, to ensure that the laser light illuminating the microelectromechanical device (MEMS) is parallel, the laser scanning equipment disclosed in this application also includes a collimating device 510. The collimating device 510 is disposed between the laser transceiver component and the MEMS 400, thereby providing collimation for the light and ensuring that the laser light emitted by the single-point laser forms a parallel beam after passing through the collimating device 510, thus improving the scanning effect of the laser light.

[0049] Specifically, the collimating device 510 can be a collimating lens. Correspondingly, the number of collimating devices 510 disposed between the laser transceiver assembly and the microelectromechanical device 400 can be one or more, forming a lens group to further improve the propagation effect of the laser light. Of course, the collimating device 510 can also be a prism or other device, as long as it has the ability to collimate light. This article does not limit its structural style. When the laser transceiver assembly includes a laser transmitter 110, the laser transceiver assembly also includes a laser detector 120 to receive the echo signal reflected back from the one-dimensional scanning galvanometer 230. In the process of arranging the laser transmitter 110 and the laser detector 120, they can be arranged alternately, and both the laser transmitter 110 and the laser detector 120 should face the microelectromechanical device 400. More specifically, along the laser emission direction of the laser emitter 110, the projections of the emission area of ​​the laser emitter 110 and the incident area of ​​the laser detector 120 can both be located within the range covered by the lens of the microelectromechanical device 400, thereby ensuring that the laser reflection effect is relatively good.

[0050] As mentioned above, the one-dimensional scanning galvanometer 230 can be installed in various positions. In this embodiment, for example... Figure 2 and Figure 3 As shown, the one-dimensional scanning galvanometer 230 is mounted on the rotating part 210. The rotating part 210 can drive the one-dimensional scanning galvanometer 230 to rotate around the drive shaft of the rotating part 210. Of course, the rotating part 210 is also mounted on the base 300. With the above technical solution, the rotating part 210 and the one-dimensional scanning galvanometer 230 are mounted together on the base 300, which can reduce the number of sources of rotational error, improve control accuracy, and thus improve the scanning effect.

[0051] Based on the above embodiments, such as Figure 1As shown, the laser scanning device also includes a converging device 520, which is disposed between the microelectromechanical device 400 and the one-dimensional scanning mirror 230. This allows the parallel light beam emitted from the microelectromechanical device 400 to converge through the converging device 520, reducing the spot area of ​​the beam when it strikes the one-dimensional scanning mirror 230. This allows the light-receiving area of ​​the one-dimensional scanning mirror 230 to be set relatively small, thereby reducing the overall size of the laser scanning device and lowering costs. Correspondingly, in addition to the converging device 520, to ensure relatively good scanning results, a collimating device 510 is also provided between the one-dimensional scanning mirror 230 and the object being scanned, so that the converged light rays on the one-dimensional scanning mirror 230 can be re-collimated. Specifically, the converging device 520 can be a converging lens, a single lens, or a lens group formed by multiple lenses. Of course, the converging device 520 can also be a prism or other devices, as long as it has the ability to converge light. This article does not limit its structural style.

[0052] In another embodiment of this application that includes a converging device 520, such as Figure 2 As shown, the converging device 520 is disposed between the one-dimensional scanning galvanometer 230 and the object being scanned, so that after the parallel beam is transmitted through the one-dimensional scanning galvanometer 230, the beam is converged by the converging device 520. At the same time, a collimating device 510 is also disposed between the converging device 520 and the optical path of the object being scanned to re-collimate the converged beam, so that the diameter and divergence angle of the outgoing beam can be adjusted to meet different system requirements.

[0053] As described above, the device mounted on the rotating part 210 can be a one-dimensional scanning galvanometer 230, or other devices, such as... Figure 3 As shown, the one-dimensional scanning galvanometer 230 is directly mounted on the base 300. In this case, the laser scanning device also includes a reflective device 240, which is disposed between the one-dimensional scanning galvanometer 230 and the optical path of the scanned object. The reflective device 240 can reflect laser light and is connected to the rotating part 210. In this case, the rotating part 210 can be driven independently, without interfering with the rotation process of the one-dimensional scanning galvanometer 230. The two can be controlled independently, which can reduce the control difficulty of the rotating part 210 and the one-dimensional scanning galvanometer 230, reduce the assembly difficulty between components, reduce the power supply difficulty of the one-dimensional scanning galvanometer 230, and improve the reliability of the system.

[0054] Specifically, the reflecting device 240 can be a reflector, which can be fixedly mounted on the rotating part 210. The orientation of the reflecting device 240 is determined based on parameters such as the specific position and orientation of the one-dimensional scanning galvanometer 230 and the microelectromechanical device 400. This ensures that the laser emitted by the laser transceiver assembly, after being reflected by the microelectromechanical device 400, can be reflected by the one-dimensional scanning galvanometer 230 and directed towards the reflecting device 240, so that it is reflected towards the scanned object. Correspondingly, the echo signal reflected back from the scanned object can be reflected at the reflecting device 240 and directed towards the one-dimensional scanning galvanometer 230. The orientation of the one-dimensional scanning galvanometer 230 can be adjusted by its own rotation, thereby changing the propagation path of the laser light beam directed towards the scanned object, achieving the purpose of changing the landing point of the laser light beam on the scanned object, and enabling the laser scanning equipment to have longitudinal scanning capability.

[0055] In addition, the laser scanning device disclosed in this application embodiment also includes a filtering unit. The filtering unit is disposed in the optical path between the laser transceiver component and the microelectromechanical device 400, so as to filter the laser light emitted by the laser transceiver component, filter out interference light, and further improve the scanning results.

[0056] Based on the laser scanning device disclosed in any of the above embodiments, this application also discloses a security system, which includes any of the above laser scanning devices. Of course, the security system may also include other components such as processing chips. Considering the brevity of the text, it will not be described in detail here.

[0057] Based on the laser scanning device disclosed in any of the above embodiments, this application also discloses a scanning control method, which is applied in the laser scanning device. The scanning control method includes:

[0058] S1. Control the one-dimensional scanning galvanometer to scan the field of view at a first resolution. Specifically, this can be achieved by controlling the one-dimensional scanning galvanometer to rotate multiple times in the circumferential direction, switching its orientation before each rotation, so that the one-dimensional scanning galvanometer can scan the corresponding area within the field of view. Furthermore, the first resolution can be set to a relatively low value to perform a faster coarse scan of the field of view. In this step, the one-dimensional scanning galvanometer moves relative to the base and provides the scanning function, while the microelectromechanical device (MEMS) acts as a reflector, reflecting the laser light and does not provide any scanning function.

[0059] The above-mentioned scanning control method also includes:

[0060] S2. When the scanned field of view includes the scanned object that satisfies the first resolution, control the microelectromechanical device to scan the scanned object at the second resolution.

[0061] Specifically, when using a one-dimensional scanning galvanometer to perform a coarse scan of the field of view, if the size of a certain object being scanned is found to meet the first resolution, the laser scanning device can be switched to the second working mode. That is, the microelectromechanical device is controlled to scan the object at the second resolution. Furthermore, since the second resolution is higher than the first resolution, the scanning accuracy of the object is higher, thus improving the reliability of the scanning results.

[0062] Optionally, step S1 above may include:

[0063] After controlling the one-dimensional scanning galvanometer to rotate by a first preset angle along the direction surrounding the second direction, the one-dimensional scanning galvanometer is controlled to rotate by a second preset angle along the direction surrounding the first direction, and the scanned field of view is scanned at a first resolution until the sum of the first preset angles is 360°, wherein the second direction is perpendicular to the first direction.

[0064] That is, in this embodiment, the one-dimensional scanning galvanometer can be controlled to rotate a second preset angle in the second direction, and then the one-dimensional scanning galvanometer can be controlled to rotate a first preset angle in the direction around the second direction, so that the one-dimensional scanning galvanometer can traverse the entire scanned field of view in the circumferential direction and complete the scanning of the area tilted within a certain range relative to the axial direction of the scanned field of view, which can improve the scanning effect of the one-dimensional scanning galvanometer.

[0065] The above embodiments of this application focus on describing the differences between the various embodiments. As long as the different optimization features between the various embodiments are not contradictory, they can be combined to form a better embodiment. For the sake of brevity, they will not be described in detail here.

[0066] The above description is merely an embodiment of this application and is not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

Claims

1. A laser scanning device, characterized by The laser scanning device comprises a laser transceiver, a rotating part, a one-dimensional scanning galvanometer, a base, and a micro-electro-mechanical device, the rotating part and the micro-electro-mechanical device are both mounted on the base, and the one-dimensional scanning galvanometer is arranged corresponding to the micro-electro-mechanical device to reflect laser light between the micro-electro-mechanical device and the one-dimensional scanning galvanometer; the one-dimensional scanning galvanometer is used to reflect laser light to a scanned object and reflect a returned signal reflected from the scanned object to the micro-electro-mechanical device; the micro-electro-mechanical device is used to reflect laser light emitted by the laser transceiver to the one-dimensional scanning galvanometer and reflect the returned signal to the laser transceiver; the one-dimensional scanning galvanometer is movably mounted on the base, and the laser light emitted from the one-dimensional scanning galvanometer rotates in a direction around a first direction, and the rotating part is used to rotate the laser light emitted from the one-dimensional scanning galvanometer in a direction around a second direction, and the first direction and the second direction are perpendicular to each other. The laser scanning device has a first working mode and a second working mode, in the first working mode, the one-dimensional scanning galvanometer moves relative to the base, the micro-electro-mechanical device is used to reflect laser light, the one-dimensional scanning galvanometer scans a scanned object at a first resolution, and in the case that the scanned object meets the first resolution, the laser scanning device switches to the second working mode; in the second working mode, the one-dimensional scanning galvanometer is stationary relative to the base, the micro-electro-mechanical device works, and is used to scan a scanned object at a second resolution, and the second resolution is higher than the first resolution.

2. The laser scanning device according to claim 1, characterized in that, The laser scanning device further comprises a collimating device arranged between the optical path between the laser transceiver and the micro-electro-mechanical device.

3. The laser scanning device of claim 2, wherein, The one-dimensional scanning galvanometer is mounted on the rotating part.

4. The laser scanning device according to claim 3, characterized in that, The laser scanning device further comprises a converging device arranged between the optical path between the micro-electro-mechanical device and the one-dimensional scanning galvanometer, and the collimating device is arranged between the optical path between the one-dimensional scanning galvanometer and the scanned object.

5. The laser scanning device according to claim 3, characterized in that, The laser scanning device further comprises a converging device arranged between the optical path between the one-dimensional scanning galvanometer and the scanned object, and the collimating device is arranged between the optical path between the converging device and the scanned object.

6. The laser scanning device of claim 2, wherein, The one-dimensional scanning galvanometer is mounted on the base, and the laser scanning device further comprises a reflecting device arranged between the optical path between the one-dimensional scanning galvanometer and the scanned object, and the reflecting device is mounted on the rotating part.

7. The laser scanning device of claim 1, wherein, The laser scanning device further comprises a filtering unit arranged on the optical path between the laser transceiver and the micro-electro-mechanical device.

8. A security system, characterized by The laser scanning device comprises any one of claims 1-7.

9. A scanning control method applied to the laser scanning device according to any one of claims 1 to 7, characterized by, The scanning control method comprises: controlling the one-dimensional scanning galvanometer to scan a scanned field of view at a first resolution; in the case that the scanned field of view comprises a scanned object meeting the first resolution, controlling the micro-electro-mechanical device to scan the scanned object at a second resolution, and the second resolution is higher than the first resolution.

10. The scanning control method according to claim 9, wherein The control of the one-dimensional scanning galvanometer to scan the scanned field of view at the first resolution comprises: After the control of the one-dimensional scanning galvanometer to rotate around the first direction by the first preset angle, the one-dimensional scanning galvanometer is controlled to rotate around the second direction by the second preset angle, and the scanned field of view is scanned at the first resolution until the sum of the first preset angles is 360°, wherein the second direction is perpendicular to the first direction.

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