Laser radar optical module, laser radar, and self-moving device

Abstract

A laser radar optical module, a laser radar, and a self-moving device, relating to the technical field of laser radars. The laser radar optical module comprises an emitting lens group (100) and a shared lens (200). The emitting lens group (100) is used for receiving a laser beam from a laser light source (300), collimating the laser beam, and then deflecting and emitting the collimated laser beam. The laser beam emitted by the emitting lens group (100) is deflected to an edge region of the shared lens (200), passes through the edge region of the shared lens (200), and is then emitted to a target object. An echo beam formed by reflection of the target object passes through a central region of the shared lens (200) and is emitted to a laser receiver (500). The emitting lens group (100) is arranged offset from the optical axis of the shared lens (200). The echo beam in the central region of the shared lens (200) is not blocked by the emitting lens group (100), thereby improving the ranging capability and ranging accuracy. The receiver and transmitter optical axes of the optical module are slightly offset from each other, but have a receiver-transmitter baseline far smaller than that of a parallel-axis optical path, so that the receiver-transmitter baseline distance is reduced, and the clear aperture of lenses is ensured, thereby improving the ranging capability and near-field ranging accuracy.

Description

A lidar optical module, lidar, and self-moving device

[0001] Cross-references to related applications

[0002] This application claims the benefit of Chinese Patent Application No. 202423212619.7, filed on December 25, 2024, the contents of which are incorporated herein by reference. Technical Field

[0003] This utility model relates to the field of lidar technology, specifically to a lidar optical module, lidar, and self-moving device. Background Technology

[0004] Current lidar designs mainly fall into two categories: coaxial optical paths and parallel axis optical paths.

[0005] In a parallel-axis optical path, the transmitting and receiving mirror groups are placed parallel to each other, creating a transmit-receive baseline. The transmit-receive baseline refers to the spatial distance or geometric offset between the transmitting and receiving ends in the optical system; it describes the relative positional relationship of the transmitted and received beams along the optical axis. Because of this baseline, near-range beam drift can lead to decreased testing accuracy or even loss of near-field signal. Reducing the transmit-receive baseline requires decreasing the lens aperture, which in turn affects the optical receiving efficiency.

[0006] Coaxial optical paths employ a central transmitter and an outer receiver, with the optical axes of the transmitting and receiving mirrors aligned on the same straight line. Therefore, optically, there is no signal offset at close range. Most current coaxial optical path solutions utilize a collimating light source with a small-aperture transmitting mirror group, and a hole is drilled in the receiving mirror group to house the transmitting light tube. The signal reflected back from the center of the receiving mirror group's optical axis is blocked by the transmitting mirror group, resulting in the loss of the highest peak signal at the center. Only the effective signal returning from the lens edge can be received, which significantly affects the ranging capability of the mirror group.

[0007] Therefore, a lidar optical path is needed that can improve short-range ranging accuracy while reducing long-range echo signal loss.

[0008] Utility Model Content

[0009] In view of the problems existing in the prior art, the present invention provides a lidar optical module, lidar and self-moving device to improve the problem that existing lidar cannot simultaneously improve the accuracy of short-range ranging and reduce the loss of long-range echo signal.

[0010] To achieve the above and other related objectives, the first aspect of this utility model provides a lidar optical module, including a transmitting mirror group and a common lens. The transmitting mirror group is used to receive a laser beam from a laser source, collimate the laser beam, and deflect it before emission. The laser beam emitted by the transmitting mirror group is deflected to the edge region of the common lens, passes through the edge region of the common lens, and then exits to a target object. The echo beam reflected by the target object passes through the central region of the common lens and exits to a laser receiver. The transmitting mirror group is offset from the optical axis of the common lens.

[0011] The transmitting lens group is offset from the optical axis of the common lens, thus preventing it from blocking the echo beam from the central region of the common lens and avoiding signal loss due to the highest central peak. The laser receiver can receive signals from the central region and most of the edge region of the common lens, effectively improving the ranging capability and accuracy of the lidar. Simultaneously, the baseline between the laser beam collimated by the transmitting lens group and the echo beam emitted from the common lens is much smaller than the transmit / receive baseline of the parallel-axis optical path, reducing the impact of near-range spot offset and effectively improving near-field ranging capability and testing accuracy. Since the common lens serves as both the transmitter and receiver, it reduces the number of lenses used in the optical module, effectively compressing the overall size of the optical module and meeting the application requirements of miniaturization and high performance for lidar.

[0012] In one embodiment of this utility model, the distance between the baseline of the laser beam after collimation by the emitting mirror group and before deflection and the optical axis of the common lens is greater than 0.5 times the maximum diameter of the emitting mirror group and less than the radius of the common lens.

[0013] After collimation and before deflection, the distance between the laser beam baseline and the optical axis of the common lens is greater than 0.5 times the maximum diameter of the transmitting lens group. This prevents the transmitting lens group from blocking the optical axis of the common lens, allowing the laser receiver to receive the echo beam from the central region of the common lens. The distance between the laser beam baseline and the optical axis of the common lens is less than the radius of the common lens. The projection of the transmitting lens group along the optical axis of the common lens at least partially coincides with the projection of the common lens along the optical axis of the common lens. This facilitates the arrangement of the transmitting lens group and the common lens, improves the compactness of the optical module, and is beneficial to the miniaturization requirements of lidar applications.

[0014] In one embodiment of the present invention, the emitting lens group includes a first incident surface and a first exit surface. The first incident surface receives the laser beam, and the first exit surface deflects the laser beam from near the optical axis of the common lens to a direction away from the optical axis of the common lens.

[0015] The transmitting lens assembly deflects the laser beam emitted from the laser source away from the optical axis of the common lens, thus shortening the distance between the laser source and the laser receiver. This simplifies the internal space design of the lidar and improves its compactness. The common lens, typically a single convex lens, acts as the receiving lens. After passing through the common lens, the laser beam is deflected towards its optical axis. The transmitting lens assembly corrects this deflection, ensuring the laser beam emitted from the common lens is collimated and maintaining the lidar's ranging capability. The combined effect of the transmitting lens assembly and the common lens eliminates the need for drilling holes in the common lens, simplifying its fabrication and assembly and reducing production costs.

[0016] In one embodiment of the present invention, the emitting lens group includes a collimation module and a redirection module; the collimation module is configured to collimate the emitted laser beam to form a collimated beam; the redirection module is configured to deflect the collimated beam from near the optical axis of the common lens to away from the optical axis of the common lens.

[0017] The collimation module transforms the divergent laser beam emitted by the laser source into a parallel, collimated beam, improving the quality and stability of the laser beam. This allows the laser beam to more accurately illuminate the target and reflect back a clearer signal. Since the beam deflects towards the optical axis of the common lens, the redirection module deflects the collimated beam away from the optical axis of the common lens. This corrects the collimation, ensuring that the laser beam emitted from the common lens is collimated and can more accurately illuminate the target, reflecting back a clearer signal.

[0018] In one embodiment of this utility model, the redirection module includes a wedge lens, a freeform surface lens, or a deflecting lens group.

[0019] In one embodiment of this utility model, the redirection is a wedge lens, the wedge lens includes a first plane and a first inclined surface, and the collimated beam is perpendicularly incident on the first plane; the first inclined surface is a plane or a freeform surface.

[0020] In one embodiment of the present invention, the first inclined surface is inclined from near the optical axis of the common lens to away from the optical axis of the common lens along the direction of the collimated beam emission.

[0021] The collimated beam is deflected away from the optical axis of the common lens after passing through the first inclined surface, so that the collimated beam enters from the off-center of the common lens.

[0022] In one embodiment of the present invention, the redirection module includes an inlet cavity, a reflection cavity, and an outlet cavity. The inlet cavity is used to inlet a collimated beam, and the collimated beam is reflected in the reflection cavity and then deflected out through the outlet cavity.

[0023] After being reflected in the reflection cavity of the redirection module, the collimated beam is deflected and emitted through the output cavity, so that the collimated beam enters the edge of the common lens, which makes it easier to control the angle of the collimated beam and ensure the detection effect of the collimated beam on the target object.

[0024] In one embodiment of this utility model, the common lens collimates the laser beam emitted by the receiving lens group and then emits it from the edge region of the common lens.

[0025] The shared lens further collimates the laser beam, thereby improving the quality and stability of the laser beam, enabling the laser beam to more accurately illuminate the target and reflect back a clearer signal.

[0026] In one embodiment of this utility model, the distance between the baseline of the laser beam after collimation by the transmitting lens group and before deflection and the optical axis of the common lens is greater than or equal to 2 mm.

[0027] By adjusting the appropriate distance between the baseline of the laser beam after collimation and before deflection by the transmitting mirror group and the optical axis of the common lens, the interference between the laser beam and the echo beam is reduced, thereby improving the ranging capability.

[0028] In one embodiment of the present invention, the lidar optical module includes a reflector group, which is configured to reflect the echo beam after being focused by the common lens to the laser receiver.

[0029] The reflector group reflects the converged echo beam at a certain angle. The reflected echo beam is at a certain angle to the original echo beam, which can shorten the distance between the laser receiver and the common lens along the optical axis of the common lens. By utilizing the space of the optical module perpendicular to the optical axis of the common lens, the overall length of the lidar is shortened, meeting the miniaturization requirements of lidar.

[0030] In one embodiment of this invention, the echo beam is perpendicular to the incident baseline and the reflection baseline of the reflector group.

[0031] By folding the echo beam by 90°, the overall length of the optical module is effectively compressed, which facilitates the design of the optical module and meets the miniaturization requirements of lidar.

[0032] The second aspect of this utility model provides a lidar optical module, including a transmitting mirror group and a common lens. The transmitting mirror group is used to receive a laser beam from a laser source and collimate the laser beam before emitting it. A through hole is provided in the edge region of the common lens. The laser beam emitted by the transmitting mirror group passes through the through hole and is emitted to the target object. The echo beam formed by the reflection of the target object passes through the central region of the common lens and is emitted to the laser receiver. The transmitting mirror group is offset from the optical axis of the common lens.

[0033] The transmitting mirror group is offset from the optical axis of the common lens, thus preventing it from blocking the echo beam from the central region of the common lens and avoiding signal loss due to the highest central peak. The laser receiver can receive signals from the central region and most of the edge region of the common lens, effectively improving the ranging capability and accuracy of the lidar. Simultaneously, the distance between the laser beam collimated by the transmitting mirror group and the echo beam emitted from the common lens is much smaller than the transmit / receive baseline of the parallel-axis optical path, thereby reducing the impact of near-range spot offset and effectively improving near-field ranging capability and testing accuracy.

[0034] A third aspect of this utility model provides a lidar, including a laser source, a laser receiver, and a lidar optical module as described above. The laser source is located on the incident light side of the emitting lens group and is used to provide a laser beam. The laser receiver is located on the output light side of the common lens that converges the echo beam and is used to receive the echo beam output by the common lens.

[0035] The lidar of this invention can receive signals from the central region of the shared lens, avoiding signal loss due to high central peak values ​​and improving ranging capability. It can also shorten the distance between the emitted laser beam and the received echo beam, thereby improving ranging capability and near-field ranging accuracy.

[0036] A fourth aspect of this utility model provides a self-moving device, including a device body and the aforementioned lidar, wherein the lidar is disposed on the device body and is used to collect three-dimensional information.

[0037] By configuring the aforementioned lidar, the self-moving device can improve its ranging capability and near-field ranging accuracy, reduce near-field measurement blind spots, and thus facilitate the planning of the self-moving device's travel path.

[0038] In combination with existing technologies, the beneficial effects of this utility model are as follows:

[0039] Existing lidar optical path designs typically employ coaxial or parallel-axis optical paths. Parallel-axis paths suffer from near-field beam drift, leading to decreased accuracy and even near-field signal loss. Reducing the transmit / receive baseline necessitates decreasing the lens aperture, further impacting optical reception efficiency. Coaxial paths, on the other hand, suffer from signal loss due to the transmission mirror group blocking the signal reflected from the optical axis center, resulting in the loss of the highest peak signal at the center and affecting the ranging capability of the mirror group. This invention comprises a transmitting mirror group and a common lens. The transmitting mirror group is offset from the optical axis of the common lens. The laser beam emitted by the laser source exits through the transmitting mirror group and then through the common lens to the target. The common lens also acts as a receiving mirror group, receiving the echo beam before it is emitted to the laser receiver. By offsetting the transmitting mirror group from the optical axis of the common lens, this invention ensures that when the common lens acts as a receiving mirror group, the echo beam in the central region is not blocked by the transmitting mirror group, thus improving ranging capability and accuracy. The optical module's transmit and receive axes are slightly offset, but the transmit and receive baselines are much smaller than those of the parallel axis optical path. This reduces the transmit and receive baseline distance while ensuring the lens aperture, thus improving ranging capability and near-field ranging accuracy. Attached Figure Description

[0040] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other embodiments can be obtained based on these drawings without creative effort.

[0041] Figure 1 is a schematic diagram of the light receiving and transmitting path of the laser radar optical module of this utility model in one embodiment;

[0042] Figure 2 is a schematic diagram of the emission optical path of the lidar optical module of this utility model in one embodiment;

[0043] Figure 3 is a schematic diagram of the light receiving and transmitting path of the laser radar optical module of this utility model in another embodiment;

[0044] Figure 4 is a schematic diagram of the redirection module in one embodiment of the lidar optical module of this utility model.

[0045] Component labeling: 100, emitting mirror group; 110, collimation module; 120, redirection module; 121, first incident surface; 122, first exit surface; 123, inlet cavity; 124, reflection cavity; 125, outlet cavity; 200, common lens; 300, laser source; 400, reflecting mirror group; 500, laser receiver. Detailed Implementation

[0046] The following specific examples illustrate the implementation of this utility model. Those skilled in the art can easily understand other advantages and effects of this utility model from the content disclosed in this specification. This utility model can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this utility model. It should be noted that, in the absence of conflict, the following embodiments and features in the embodiments can be combined with each other. It should also be understood that the terminology used in the embodiments of this utility model is for describing specific implementation schemes and not for limiting the scope of protection of this utility model. Test methods in the following embodiments that do not specify specific conditions are generally performed under conventional conditions or according to the conditions recommended by the respective manufacturers.

[0047] When numerical ranges are given in the embodiments, it should be understood that, unless otherwise specified in this invention, both endpoints of each numerical range and any value between the two endpoints may be selected. Unless otherwise defined, all technical and scientific terms used in this invention, as well as the prior art known to those skilled in the art and the description of this invention, may be implemented using any prior art methods, equipment, and materials similar to or equivalent to those in the embodiments of this invention.

[0048] It should be noted that the terms such as "upper," "lower," "left," "right," "middle," and "one" used in this specification are merely for clarity of description and are not intended to limit the scope of implementation of this utility model. Any changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of implementation of this utility model.

[0049] Existing lidar designs include two types: coaxial and parallel-axis optical paths. In parallel-axis paths, the transmitting and receiving mirrors are placed parallel to each other. Due to the existence of a transmit / receive baseline, near-range beam drift leads to decreased testing accuracy and even near-field signal loss, affecting near-field ranging capabilities. Reducing the transmit / receive baseline requires decreasing the lens aperture, which also affects optical receiving efficiency and ranging capability. In coaxial paths, a center-transmitting, outer-receiving configuration is typically used. The signal reflected from the center of the receiving mirror's optical axis is blocked by the transmitting mirror, resulting in the loss of the highest peak signal at the center, affecting the ranging capability of the mirror group. Therefore, this application provides a lidar optical module and lidar that, by offsetting the transmitting mirror group from the optical axis of a common lens, ensures that the signal received in the central region of the common lens is not blocked by the transmitting mirror group. Most of the echo signal can be received, and even the strong specular reflection signal at the center can be received by the common lens and reach the laser receiver, thereby improving ranging capability. The laser beam emitted from the shared lens and the echo beam received by the shared lens have a smaller distance between them, reducing the near-field ranging blind zone and improving near-field ranging capability.

[0050] Please refer to Figures 1 to 4. A first aspect of this utility model provides a lidar optical module, including a transmitting mirror group 100 and a common lens 200. The transmitting mirror group 100 receives a laser beam from a laser source 300, collimates the laser beam, and deflects it before emission. The laser beam emitted from the transmitting mirror group 100 is deflected to the edge region of the common lens 200, passes through the edge region of the common lens 200, and then exits to a target object. The echo beam reflected by the target object passes through the central region of the common lens 200 and exits to a laser receiver 500. The transmitting mirror group 100 is offset from the optical axis of the common lens 200.

[0051] The emitting lens group 100 collimates the laser beam emitted by the laser source 300, forming a collimated beam and improving its quality and stability. The collimated beam is deflected and emitted to the edge region of the common lens 200, and then exits from the edge region of the common lens 200 to the target object. Through the combined action of the emitting lens group 100 and the common lens 200, the collimated beam emitted from the common lens 200 is parallel or substantially parallel to the optical axis of the common lens 200, ensuring that the collimated beam accurately reaches the target and improving ranging capability. The combined action of the emitting lens group 100 and the common lens 200 on the laser beam eliminates the need for drilling holes in the common lens 200, simplifying its production and assembly. The shared lens 200 serves two purposes: as part of the transmitter, where the collimated beam formed by the transmitting lens group 100 passes through the shared lens 200 and exits to the target; and as part of the receiver, it gathers the echo beam formed after detecting the target and exits it to the laser receiver 500. This reduces the transmit / receive baseline, decreases the near-field detection blind zone, and improves near-field ranging capability. The shared lens 200 serves both as the transmitter and receiver, reducing the number of lenses used in the optical module and effectively compressing the overall size of the optical module, meeting the application requirements of miniaturization and high performance for lidar. The transmitting lens group 100 is offset from the optical axis of the shared lens 200, ensuring that the transmitting lens group 100 does not block the echo beam in the central region of the shared lens 200, avoiding signal loss due to the highest central peak. The laser receiver 500 can receive signals from the central region and most of the edge region of the shared lens 200, effectively improving the ranging capability and accuracy of the lidar.

[0052] In one embodiment, the distance between the baseline of the laser beam after collimation by the transmitting mirror group 100 and before deflection and the optical axis of the common lens 200 is greater than 0.5 times the maximum diameter of the transmitting mirror group 100. This prevents the transmitting mirror group 100 from blocking the optical axis of the common lens 200, allowing the laser receiver 500 to receive the echo beam from the central region of the common lens 200. The distance between the baseline of the laser beam after collimation by the transmitting mirror group 100 and before deflection and the optical axis of the common lens 200 is less than the radius of the common lens 200. The projection of the transmitting mirror group 100 along the optical axis of the common lens 200 at least partially coincides with the projection of the common lens 200 along the optical axis of the common lens 200, facilitating the arrangement of the transmitting mirror group 100 and the common lens 200, improving the compactness of the optical module, and benefiting the application requirements of miniaturized lidar.

[0053] It should be noted that the maximum diameter of the transmitting lens group 100 refers to the following: the transmitting lens group 100 can be composed of multiple optical lenses, each with its own diameter. The diameters of all optical lenses form a set of diameters, and the largest diameter in the set is the maximum diameter of the transmitting lens group 100. Of course, the transmitting lens group 100 can also have only one optical lens. In this case, the diameter of that optical lens is the maximum diameter of the transmitting lens group 100.

[0054] In one embodiment, the emitting lens group 100 includes a first incident surface 121 and a first exit surface 122. The first incident surface 121 receives the laser beam, and the first exit surface 122 deflects the laser beam from near the optical axis of the common lens 200 to a direction away from the optical axis of the common lens 200. The emitting lens group 100 may include a collimating lens and a deflecting lens, wherein the incident surface of the collimating lens is the first incident surface 121, and the exit surface of the deflecting lens is the first exit surface 122. The laser beam emitted by the laser source 300 enters the collimating lens through the first incident surface 121, and forms a collimated beam after passing through the collimating lens. The collimated beam is then deflected by the deflecting lens to a direction away from the optical axis of the common lens 200 before exiting. This shortens the distance between the laser source 300 and the laser receiver 500, facilitating the internal space design of the lidar and improving the compactness of the lidar. The common lens 200 serves as the receiving lens. Taking a single convex lens as an example, the collimated laser beam is deflected towards the optical axis of the common lens 200 after passing through it. The emitting lens group 100 corrects this deflection of the laser beam away from the optical axis of the common lens 200, ensuring that the laser beam emitted from the common lens 200 is collimated and parallel or substantially parallel to its optical axis. This guarantees that the collimated beam accurately reaches the target, improving ranging capability. The combined effect of the emitting lens group 100 and the common lens 200 on the laser beam eliminates the need for drilling holes in the common lens 200, simplifying its processing and assembly and reducing production costs.

[0055] Referring to Figure 2, in one embodiment, the emitting lens assembly 100 includes a collimation module 110 and a redirection module 120. The collimation module 110 is configured to collimate the emitted laser beam into a collimated beam. The collimation module 110 converts the divergent laser beam emitted by the laser source 300 into a parallel collimated beam, improving the quality and stability of the laser beam, allowing the laser beam to more accurately illuminate the target object and reflect back a clearer signal. The redirection module 120 is configured to deflect the collimated beam from near the optical axis of the common lens 200 to away from the optical axis of the common lens 200. Because the light beam is deflected towards the optical axis of the common lens 200 when it passes through the common lens 200, the redirection module 120 can be used to deflect the straight beam away from the optical axis of the common lens 200. This can correct the straight beam, making the laser beam emitted from the common lens 200 a collimated beam that is parallel or substantially parallel to the optical axis of the common lens 200. This ensures that the laser beam can more accurately illuminate the target under test and reflect back a clearer signal. By correcting the direction of the straight beam through the redirection module 120, the common lens 200 also plays a role in optical path collimation at the transmitting end. Therefore, there is no need to perform secondary morphological processing such as drilling holes on the common lens 200, reducing the processing steps of the common lens 200, lowering production costs, and facilitating assembly.

[0056] In one embodiment, the collimation module 110 is configured as a single aspherical lens. When collimation is achieved using a single aspherical lens, the system cost is low and the assembly and adjustment are simple.

[0057] A single aspherical lens can be either a biconvex single lens or a plano-convex single lens. When the aspherical lens is a biconvex single lens, both its incident and exit surfaces are convex. The focal length is longer in the middle of the lens surface and shorter at the ends of each surface. Biconvex single lenses are mainly used to converge light from point sources or to transmit images to other optical systems. The radii of curvature of its incident and exit surfaces can be equal, giving the lens symmetry, minimizing spherical aberration, and eliminating coma and distortion. Of course, the radii of curvature of the incident and exit surfaces of a biconvex single lens can also be unequal. Alternatively, a single aspherical lens can also be a plano-convex single lens, where one of the incident and exit surfaces is a plane and the other is a convex surface. Specifically, the incident surface can be a plane and the exit surface a convex surface; alternatively, the incident surface can be convex and the exit surface a plane. As shown in Figure 2, the incident surface of the plano-convex single lens in this application is a plane and the exit surface is a convex surface. Of course, the aspherical lens can also be other surface shapes, and is not limited to the above-mentioned biconvex single lens and plano-convex single lens, as long as the collimation module 110 can achieve the collimated beam after shaping.

[0058] In another possible implementation of this application, the collimation module 110 is configured as a collimating lens group. When collimating with a collimating lens group, it can meet more stringent system size requirements. The collimating lens group may include multiple lenses arranged in sequence to achieve collimation, and the processing accuracy requirements of the lenses themselves are lower than those of a single aspherical lens.

[0059] Of course, as another alternative, the collimation module 110 can also be configured as a single spherical lens, which is a biconvex lens or a plano-convex lens, to achieve collimation and form a collimated beam.

[0060] Referring to Figure 2, in one embodiment, the redirection module 120 is configured as a wedge lens with a wedge-shaped cross-section and a thickness that gradually changes in one direction. When the light beam passes through the wedge lens, it is deflected, thereby changing the direction of light propagation.

[0061] In one embodiment, the wedge lens includes a first plane and a first inclined plane. The collimated beam is perpendicularly incident on the first plane and then deflected out by the first inclined plane in a direction away from the optical axis of the common lens 200, so that the collimated beam enters from the edge region of the common lens 200.

[0062] In one embodiment, the first inclined surface is a plane, and the first inclined surface is inclined from near the optical axis of the common lens 200 to away from the optical axis of the common lens 200 along the direction of the collimated beam emission, so that the collimated beam is deflected away from the optical axis of the common lens 200 after passing through the first inclined surface, and the collimated beam enters from the edge region of the common lens 200.

[0063] Of course, as some alternatives, the first inclined surface can also be a freeform surface, which can deflect the collimated beam away from the optical axis of the common lens 200 so that the collimated beam enters from the edge region of the common lens 200.

[0064] In another possible implementation of this application, the redirection module 120 is configured as a deflecting lens group. When collimating using a deflecting lens group, more stringent system size requirements can be met. The deflecting lens group may include multiple lenses arranged sequentially to achieve deflection of the collimated beam, and the processing accuracy requirements of the lenses themselves are lower than those of a single lens.

[0065] Of course, as some alternatives, the redirection module 120 can also be configured as a freeform lens, etc., so that the collimated beam is deflected away from the optical axis of the common lens 200, and the collimated beam enters from the off-center of the common lens 200.

[0066] Referring to Figure 4, in one embodiment, the redirection module 120 includes an inlet cavity 123, a reflection cavity 124, and an outlet cavity 125. The inlet cavity 123 is used to inlet the collimated beam. After being reflected in the reflection cavity 124, the collimated beam is deflected and exited through the outlet cavity 125. The collimated beam, after being reflected in the reflection cavity 124 of the redirection module 120, is deflected and exited through the outlet cavity 125, allowing the collimated beam to enter the edge of the common lens 200. The collimated beam can be reflected multiple times within the reflection cavity 124 to control the angle of the collimated beam and ensure the detection effect of the collimated beam on the target object.

[0067] Referring to Figures 1 and 2, in one embodiment, the common lens 200 is configured as an aspherical lens; the aspherical lens is a plano-convex lens or a biconvex lens, and the spherical lens is a plano-convex lens or a biconvex lens.

[0068] A single aspherical lens can be either a biconvex lens or a plano-convex lens. When the aspherical lens is a biconvex lens, both the incident and exit surfaces are convex, with a longer focal length in the middle and shorter focal lengths at the ends of each surface. Alternatively, a single aspherical lens can also be a plano-convex lens, where one of the incident and exit surfaces is a plane and the other is a convex surface. Referring to Figure 2, in this application, when the plano-convex lens is used as the transmitter, the incident surface is a plane and the exit surface is a convex surface; when the plano-convex lens is used as the receiver, the incident surface is a convex surface and the exit surface is a plane. Of course, the aspherical lens can also have other surface shapes, not limited to the aforementioned biconvex and plano-convex lenses, as long as it allows the collimated beam to accurately reach the object under test, and after receiving the echo beam, it is converged and emitted to the laser receiver 500.

[0069] In another feasible embodiment, the common lens 200 is configured as a spherical lens, wherein the individual spherical lens is a plano-convex lens or a biconvex lens. When the spherical lens is a single convex lens, one of the incident surface and the exit surface of the plano-convex lens is a plane and the other is a convex surface; when the spherical lens is a biconvex lens, both the incident surface and the exit surface of the biconvex lens are convex surfaces.

[0070] Of course, as some alternatives, the shared lens 200 can also be other types of lenses or lens groups to meet the requirements of being used as both a transmitter and a receiver, so that the collimated beam accurately reaches the object under test, and after receiving the echo beam, the echo beam is converged and emitted to the laser receiver 500.

[0071] In one embodiment, the common lens 200 collimates the laser beam emitted from the transmitting lens group 100 and then emits it from the edge region of the common lens 200. The common lens 200 further collimates the laser beam, thereby improving the quality and stability of the laser beam, so that the laser beam can more accurately illuminate the target under test and reflect back a clearer signal.

[0072] In one embodiment, the distance between the baseline of the laser beam after collimation and before deflection by the transmitting lens group 100 and the optical axis of the common lens 200 is greater than or equal to 2 mm, such as 2 mm, 3 mm, 4 mm, etc. By adjusting the appropriate distance between the baseline of the laser beam after collimation and before deflection by the transmitting lens group 100 and the optical axis of the common lens 200, the interference between the laser beam and the echo beam is reduced, and the ranging capability is improved.

[0073] Referring to Figure 3, in one embodiment, the lidar optical module includes a reflector group 400, which is configured to reflect the echo beam converged by the common lens 200 to the laser receiver 500. The reflector group 400 reflects the converged echo beam at a certain angle, and the reflected echo beam forms a certain angle with the original echo beam, thereby shortening the distance between the laser receiver 500 and the common lens 200 along the optical axis of the common lens 200. By utilizing the space of the optical module perpendicular to the optical axis of the common lens 200, the overall length of the lidar is shortened, meeting the requirement of lidar miniaturization.

[0074] The mirror group 400 can be configured as a single mirror or multiple mirrors; the mirrors can be plane mirrors, spherical mirrors or aspherical mirrors, which can reflect the echo beam after being gathered by the common lens 200 to the laser receiver 500 at a certain angle.

[0075] Referring to Figure 3, in one embodiment, the echo beam is perpendicular to the incident and reflected baselines of the reflector assembly 400. By folding the echo beam by 90°, the overall length of the optical module is effectively compressed, facilitating the design of the optical module and meeting the miniaturization requirements of lidar.

[0076] The second aspect of this utility model provides a lidar optical module, including a transmitting mirror group 100 and a common lens 200. The transmitting mirror group 100 is used to receive a laser beam from a laser source 300 and collimate the laser beam before emitting it. The common lens 200 has a through hole in its edge region. The laser beam emitted from the transmitting mirror group 100 passes through the through hole and is emitted to the target object. The echo beam formed by the reflection from the target object passes through the central region of the common lens 200 and is emitted to the laser receiver 500. The transmitting mirror group 100 is offset from the optical axis of the common lens 200 so that the transmitting mirror group 100 does not block the echo beam in the central region of the common lens 200, avoiding signal loss due to the highest peak in the central region. The laser receiver 500 can receive signals from the central region and most of the edge region of the common lens 200, effectively improving the ranging capability and ranging accuracy of the lidar. Meanwhile, the baseline between the laser beam collimated by the transmitting lens group 100 and the echo beam emitted from the common lens 200 is much smaller than the transmit and receive baseline of the parallel axis optical path, thereby reducing the influence of near-range spot offset and effectively improving near-field ranging capability and testing accuracy. By setting a through hole in the common lens 200, the laser beam can pass through the common lens 200 easily, reducing the interference of the common lens 200 on the laser beam. At this time, the common lens 200 is only used to collimate the beam, without refraction or reflection of the collimated beam.

[0077] In one embodiment, the transmitting lens assembly 100 includes a collimation module 110, a redirection module 120, and a correction module: the collimation module 110 is configured to collimate the emitted laser beam into a collimated beam; the redirection module 120 is configured to deflect the collimated beam towards the edge region of the common lens 200; and the correction module is configured to correct the collimated beam emitted by the redirection module 120 to be parallel to the optical axis of the common lens 200. The common lens 200 does not interfere with the collimated beam; to obtain better detection results, the collimated beam is preferably parallel or substantially parallel to the optical axis of the common lens 200 when passing through it. Through the combined action of the collimation module 110, the redirection module 120, and the correction module, the laser beam emitted from the laser source 300 is deflected to the edge region of the common lens 200 for emission. This not only shortens the distance between the laser source 300 and the laser receiver 500, effectively compressing the overall size of the optical module and meeting the application requirements of miniaturization and high performance of lidar, but also shapes the laser beam, improving the quality and stability of the emitted laser beam, so that the laser beam can accurately illuminate the target object and reflect back a clearer signal.

[0078] Collimation module 110 can be configured as a single aspherical lens, such as a single convex lens or a double convex lens; collimation module 110 can also be configured as a single spherical lens, such as a single convex spherical lens or a double convex spherical lens; collimation module 110 can also be configured as a collimating lens group to achieve collimation and form a collimated beam. Redirection module 120 can be configured as a wedge lens, a freeform surface lens, or a deflecting lens group, etc.

[0079] In one embodiment, the correction module can be configured as a wedge lens, a freeform lens, or a correction lens group. The correction module deflects the collimated beam emitted from the redirection module 120, ensuring that the baseline of the collimated beam emitted to the target is parallel or substantially parallel to the optical axis of the common lens 200. This allows the collimated beam to accurately reach the target and form an echo beam.

[0080] A third aspect of this invention provides a lidar system, comprising a laser source 300, a laser receiver 500, and the lidar optical module described in any one of the above descriptions. The laser source 300 is located on the incident light side of the emitting mirror group 100 and is used to provide a laser beam. The laser receiver 500 is located on the emitting light side of the common lens 200 where the echo beam is converged, and is used to receive the echo beam output by the common lens 200. The lidar system of this invention can receive signals from the central region of the common lens 200, avoiding signal loss due to high central peak values ​​and improving ranging capability. It can also shorten the distance between the emitted laser beam and the received echo beam, improving ranging capability and near-field ranging accuracy.

[0081] A fourth aspect of this utility model provides a self-moving device, including a device body and the aforementioned lidar. The lidar is mounted on the device body and is used to collect three-dimensional information. Specifically, the lidar can be installed on the top of the device body or on the side wall of the device body. By configuring the lidar, the self-moving device can improve its ranging capability and near-field ranging accuracy, reduce near-field measurement blind spots, and thus facilitate the planning of the self-moving device's travel path. The self-moving device can be a household appliance such as a robot vacuum cleaner or floor scrubber, a garden tool such as a lawnmower or snowplow, an all-terrain vehicle or car, or other self-moving devices configured with the aforementioned lidar. The self-moving device also includes other components; please refer to existing self-moving devices for details, which will not be elaborated upon in this application.

[0082] This invention relates to a laser radar optical module, a laser radar, and a self-moving device. The transmitting mirror group 100 is offset from the optical axis of the common lens 200. The laser beam emitted by the laser source 300 passes through the transmitting mirror group 100, then through the common lens 200 to the target object. The common lens 200 also acts as a receiving mirror group, receiving the echo beam before it is emitted to the laser receiver 500. By offsetting the transmitting mirror group 100 from the optical axis of the common lens 200, this invention ensures that when the common lens 200 acts as a receiving mirror group, the echo beam in the central region is not blocked by the transmitting mirror group 100, thus improving ranging capability and accuracy. Although the transmitting and receiving axes of the optical module are slightly offset, the transmitting and receiving baselines are much smaller than those of the parallel-axis optical path, thereby reducing the transmitting and receiving baselines while maintaining the lens aperture, improving ranging capability and near-field ranging accuracy. Therefore, this invention effectively overcomes some practical problems in the prior art and has high utilization value and practical significance.

[0083] The above embodiments are merely illustrative of the principles and effects of this utility model and are not intended to limit the scope of this utility model. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of this utility model. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in this utility model should still be covered by the claims of this utility model.

Claims

1. A lidar optical module, characterized in that, include: The emitting mirror group is used to receive the laser beam from the laser source and collimate and deflect the laser beam before emission. A common lens is used, in which the laser beam emitted from the emitting lens group is deflected to the edge region of the common lens and then emitted to the target object after passing through the edge region of the common lens. The echo beam formed by the reflection of the target object passes through the central region of the common lens and is emitted to the laser receiver. The emitting lens group is offset from the optical axis of the common lens.

2. The lidar optical module according to claim 1, characterized in that, The distance between the baseline of the laser beam after collimation by the emitting mirror group and before deflection and the optical axis of the common lens is greater than 0.5 times the maximum diameter of the emitting mirror group and less than the radius of the common lens.

3. The lidar optical module according to claim 1, characterized in that, The emitting lens group includes a first incident surface and a first exit surface. The first incident surface receives the laser beam, and the first exit surface deflects the laser beam from near the optical axis of the common lens to a direction away from the optical axis of the common lens.

4. The lidar optical module according to claim 1, characterized in that, The transmitting mirror assembly includes: A collimation module configured to collimate the emitted laser beam into a collimated beam; A redirection module is configured to deflect the collimated beam from near the optical axis of the common lens to away from the optical axis of the common lens.

5. The lidar optical module according to claim 4, characterized in that, The redirection module includes a wedge lens, a freeform surface lens, or a deflecting lens group.

6. The lidar optical module according to claim 4, characterized in that, The redirection module is a wedge lens, which includes a first plane and a first inclined surface. The collimated beam is perpendicularly incident on the first plane. The first inclined surface is a plane or a freeform surface.

7. The lidar optical module according to claim 6, characterized in that, The first inclined surface is inclined along the direction of the collimated beam emission from a point near the optical axis of the common lens and away from the optical axis of the common lens.

8. The lidar optical module according to claim 4, characterized in that, The redirection module includes an inlet cavity, a reflection cavity, and an outlet cavity. The inlet cavity is used to inlet the collimated beam, and the collimated beam is reflected in the reflection cavity and then deflected and exited through the outlet cavity.

9. The lidar optical module according to claim 1 or 6, characterized in that, The common lens collimates the laser beam emitted from the receiving lens group and then emits it from the edge region of the common lens.

10. The lidar optical module according to claim 1, characterized in that, The distance between the baseline of the laser beam after collimation by the transmitting lens group and before deflection and the optical axis of the common lens is greater than or equal to 2 mm.

11. The lidar optical module according to claim 1, characterized in that, include: A mirror assembly configured to reflect the echo beam converged by the common lens to the laser receiver.

12. The lidar optical module according to claim 11, characterized in that, The echo beam is perpendicular to the incident and reflected baselines of the mirror assembly.

13. A lidar optical module, characterized in that, include: The emitting mirror group is used to receive the laser beam from the laser source and collimate the laser beam before emitting it. A common lens is provided with a through hole in the edge area. The laser beam emitted from the emitting lens group passes through the through hole and is emitted to the target object. The echo beam formed by the reflection of the target object passes through the central area of ​​the common lens and is emitted to the laser receiver. The emitting lens group is offset from the optical axis of the common lens.

14. A lidar, characterized in that, The system includes a laser source, a laser receiver, and a lidar optical module according to any one of claims 1 to 13. The laser source is located on the incident light side of the emitting lens group and is used to provide a laser beam. The laser receiver is located on the output light side of the common lens that converges the echo beam and is used to receive the echo beam output by the common lens.

15. A self-moving device, characterized in that, The device includes a main body and the lidar as described in claim 14, wherein the lidar is mounted on the main body and is used to collect three-dimensional information.

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