Scanning module and laser radar

Abstract

The utility model provides a scanning module and a laser radar, and relates to the technical field of laser radars. The scanning module has a first preset axis and a second preset axis which are perpendicular to each other, the scanning module comprises a refractive optical element, a first driving element and a second driving element, the refractive optical element is connected to the first driving element, the first driving element is used for driving the refractive optical element to rotate around the first preset axis, and the second driving element is used for driving the refractive optical element to rotate around the second preset axis. The refractive optical element is used for receiving and refracting light beams incident in the direction parallel to the first preset axis, the first driving element is connected to the second driving element, and the second driving element is used for driving the first driving element to rotate around the second preset axis. By improving the scanning module of the laser radar, the pitching field angle of the laser radar is increased.

Description

Technical Field

[0001] The present application relates to the field of laser radar technology, and in particular to a scanning module and a laser radar. Background Art

[0002] With the development of LiDAR technology, LiDAR has various scanning methods. In the field of three-dimensional mapping and vehicle-mounted radar, radar is often required to scan a large field of view. When it comes to large-angle scanning in the vertical direction, the radar system has stability problems. For example, large up and down swings at high frequencies will affect the measurement accuracy and cause additional pressure on mechanical components. Therefore, the conventional mechanical radar azimuth field of view can reach 360°, but the pitch field of view is small, which cannot meet the needs of the market and has limited application scenarios.

[0003] Based on this, how to increase the elevation field of view of the mechanical radar to meet market demand is a technical problem that technicians in this field urgently need to solve. Utility Model Content

[0004] In view of this, the purpose of this application is to overcome the deficiencies in the prior art and to provide a scanning module and a laser radar, thereby increasing the pitch and elevation field of view of the laser radar by improving the scanning module of the laser radar.

[0005] This application provides the following technical solutions:

[0006] In a first aspect, an embodiment of the present application provides a scanning module, wherein the scanning module has a first preset axis and a second preset axis arranged perpendicular to each other, the scanning module includes a refractive optical element, a first driving element and a second driving element, the refractive optical element is arranged on the first driving element, the first driving element is used to drive the refractive optical element to rotate around the first preset axis, the refractive optical element is used to receive and refract a light beam incident along a direction parallel to the first preset axis, the first driving element is arranged on the second driving element, and the second driving element is used to drive the first driving element to rotate around the second preset axis.

[0007] In some embodiments of the first aspect, the refractive optical element has an exit surface and an incident surface, and ends of the exit surface and the incident surface of the refractive optical element that are close to each other are arranged to be tilted toward each other.

[0008] In some embodiments of the first aspect, the first driving element includes a first driving motor, the main shaft of the first driving motor is configured as a hollow shaft, the axis of the hollow shaft coincides with the rotation axis of the refractive optical element; wherein the refractive optical element is disposed in the hollow shaft.

[0009] In some embodiments of the first aspect, a slope of the exit surface is smaller than a slope of the incident surface.

[0010] In some embodiments of the first aspect, the scanning module further includes a weight element, the refractive optical element is formed with a thick end and a thin end, and the weight element is disposed on the thin end.

[0011] In some embodiments of the first aspect, the refractive optical element comprises a wedge-shaped mirror.

[0012] In a second aspect, the present application further provides a laser radar, the laser radar comprising:

[0013] A scanning module, wherein the scanning module is the scanning module described in any one of the above embodiments;

[0014] A turntable, a laser emitting module and a laser receiving module, wherein the laser emitting module is used to emit a light beam, and the laser receiving module is used to receive a return light beam. The first driving element, the laser emitting module and the laser receiving module are all arranged on the turntable. The turntable and the first driving element are both arranged on the second driving element of the scanning module, and the second driving element is used to drive the turntable to rotate around the second preset axis.

[0015] In some embodiments of the second aspect, the laser receiving module further includes:

[0016] N-level first reflecting optical elements, the N-level first reflecting optical elements are arranged on the turntable, the N-level first reflecting optical elements are used to receive and reflect N times the returning light beam refracted by the refractive optical element, and satisfy: N≥1, N is a positive integer;

[0017] At least one focusing optical element, which is disposed on the turntable, and in the propagation direction of the return light beam, at least one focusing optical element is disposed upstream or downstream of at least one of the first reflecting optical elements, and is used to receive and focus the return light beam;

[0018] A detector is arranged on the turntable. In the propagation direction of the return light beam, the detector is located at the most downstream position. The detector is used to receive the return light beam.

[0019] In some embodiments of the second aspect, the scanning module further includes:

[0020] a laser, the laser being used to emit the light beam;

[0021] M-level second reflecting optical elements, the M-level second reflecting optical elements are used to receive and reflect the light beam emitted by the laser M times, so that the light beam propagates in a direction parallel to the first preset axis, and satisfying: M≥1, M is a positive integer;

[0022] At least one collimating optical element is provided upstream or downstream of at least one of the second reflecting optical elements in the propagation direction of the light beam to shrink the divergence angle of the light beam; and the laser and the detector are respectively provided on both sides of the first preset axis.

[0023] In some embodiments of the second aspect, the first reflective optical element is a first reflector, and in the propagation direction of the light beam, the first reflector is disposed upstream of the refractive optical element, and the first reflector has a light-transmitting hole, so that the light beam can pass through the light-transmitting hole and enter the refractive optical element;

[0024] and / or, the second reflective optical element comprises a second reflector;

[0025] and / or, the focusing optical element comprises a receiving lens;

[0026] And / or, the collimating optical element comprises a collimating mirror.

[0027] The embodiments of the present application have the following advantages:

[0028] The present application provides a scanning module, which has two mutually perpendicular preset axes, namely a first preset axis and a second preset axis, which allows the light beam to be scanned on two different planes. The first driving element is equipped with a refractive optical element and is responsible for driving the refractive optical element to rotate around the first preset axis (usually a horizontal axis). In this way, the scanning range of the light beam in the vertical direction can be controlled. The refractive optical element is used to receive a light beam incident in a direction parallel to the first preset axis and change its propagation path. Due to the presence of the refractive optical element, the incident light beam will be emitted at a new angle after refraction, and this process enables the light beam to cover a larger angle range in the vertical direction. The design of the refractive optical element ensures the effective operation of the transmitting light path and the receiving light path, while avoiding the field of view limitation problem caused by structural occlusion. The second driving element is installed on the second preset axis, driving the entire assembly including the first driving element and the refractive optical element to rotate around the second preset axis (usually a vertical axis).

[0029] This not only realizes the scanning of the light beam in the vertical direction, but also supports large-angle scanning in the horizontal direction, thereby significantly increasing the pitch field of view. The first drive element and the second drive element are directly connected to form a compact and stable mechanical structure, which improves the stability during the scanning action and helps to maintain high-precision measurement results and increase the field of view.

[0030] Obviously, a larger pitch angle means that the LiDAR can cover more types of complex environments, such as urban areas with tall buildings or space monitoring under bridges, which enhances the adaptability and practicality of the equipment. In addition, it helps to reduce the size and weight of the scanning module, making the LiDAR more portable and easy to integrate into various mobile platforms.

[0031] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and understandable, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0033] Figure 1 A schematic diagram of the structure of a laser radar according to an embodiment of the present application is shown;

[0034] Figure 2 A schematic diagram of the structure of a laser radar from another perspective provided by an embodiment of the present application is shown;

[0035] Figure 3 A schematic structural diagram of another viewing angle of a laser radar provided in an embodiment of the present application is shown;

[0036] Figure 4 A schematic diagram showing the results of Experiment 1 provided in an embodiment of the present application is shown;

[0037] Figure 5 A schematic diagram showing the results of Experiment 2 provided in an embodiment of the present application is shown;

[0038] Figure 6 A schematic diagram showing the results of Experiment 3 provided in the embodiments of the present application is shown.

[0039] Description of main component symbols:

[0040] 100-laser; 200-first collimator; 300-turntable; 400-second reflective optical element; 500-second collimator; 600-first driving element; 700-first reflective optical element; 710-light-transmitting hole; 800-refractive optical element; 900-receiving lens; 1000-detector; 1100-second driving element. DETAILED DESCRIPTION

[0041] The embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and cannot be understood as limiting the present application.

[0042] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. In contrast, when an element is referred to as being "directly on" another element, there is no intermediate element. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only.

[0043] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0044] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0045] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of the template are only for the purpose of describing specific embodiments and are not intended to limit this application. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0046] In the related technology, with the development of LiDAR technology, LiDAR has various scanning methods. In the field of three-dimensional mapping and vehicle-mounted radar, radar is often required to scan a large field of view. When it comes to large-angle scanning in the vertical direction, the radar system has stability problems. For example, large up and down swings at high frequencies will affect the measurement accuracy and cause additional pressure on mechanical components. Therefore, the conventional mechanical radar azimuth field of view can reach 360°, but the pitch field of view is small, which cannot meet the needs of the market and has limited application scenarios.

[0047] As shown in Figures 1, 2 and Figure 3 As shown, in order to solve the above technical problems, an embodiment of the present application provides a scanning module, which has a first preset axis and a second preset axis arranged perpendicular to each other, and the scanning module includes a refractive optical element 800, a first driving element 600 and a second driving element 1100, the refractive optical element 800 is arranged on the first driving element 600, the first driving element 600 is used to drive the refractive optical element 800 to rotate around the first preset axis, the refractive optical element 800 is used to receive and refract a light beam incident along a direction parallel to the first preset axis, the first driving element 600 is arranged on the second driving element 1100, and the second driving element 1100 is used to drive the first driving element 600 to rotate around the second preset axis.

[0048] In these embodiments, the solution provided in the present application is an improved scanning module designed to expand the pitch and elevation field of view of a laser radar (LiDAR).

[0049] It should be noted that the field of view of traditional mechanical laser radars in the pitch direction is limited, usually between 20 and 40 degrees, which limits its application scenarios. This application introduces a scanning module with a first preset axis and a second preset axis that are perpendicular to each other, and combines a refractive optical element 800 and a first drive element 600 and a second drive element 1100 to achieve a larger pitch field of view. In the new laser radar scanning method, the azimuth field of view can reach 360°, and the pitch field of view can reach 70°. In other words, in actual applications, the horizontal FOV (Field of View) is close to 360°, and the vertical FOV (Field of View) is 70° or more.

[0050] Among them, the first preset axis and the second preset axis are arranged perpendicular to each other, providing the scanning module with the ability of two-dimensional rotation. In this embodiment, taking the first preset axis as a horizontal line and the second preset axis as a vertical line as an example, it can rotate in the vertical plane (around the first preset axis) and can also rotate in the horizontal plane (around the second preset axis).

[0051] The refractive optical element 800 is mounted on the first driving element 600, and the first driving element 600 is responsible for receiving and changing the direction of the incident light beam. The light beam enters in a direction parallel to the first preset axis, and is deflected after passing through the refractive optical element 800, thereby changing the exit angle of the light beam. The function of the first driving element 600 is to drive the refractive optical element 800 to rotate around the first preset axis, so that the scanning range of the light beam in the vertical direction can be controlled.

[0052] Obviously, the refractive optical element 800 is placed vertically. For the emission optical path, the light beam is incident from the side with a larger slope and is emitted from the side with a smaller slope. For the receiving optical path, the return light beam is incident from the side with a smaller slope and is emitted from the side with a larger slope. The refractive optical element 800 will refract the light beam emitted from the inside on the outer surface, so that the light beam at the time of emission and the light beam at the time of incidence form an angle θ. As the refractive optical element 800 rotates, the light beam will generate a solid angle of 2θ, that is, there is a field of view angle of 2θ in the vertical direction, forming a symmetrical field of view angle.

[0053] The second driving element 1100 has a second preset axis, which is used to drive the entire assembly including the first driving element 600 and the refractive optical element 800 to rotate around the second preset axis. This allows the light beam to scan not only in the vertical direction, but also in the horizontal direction at a large angle. Furthermore, since there is no obstruction on one side of the outgoing light beam on the refractive optical element 800, it is obvious that the pitch field angle can be increased. In addition, since the first driving element 600 and the second driving element 1100 are directly connected, it is equivalent to an integrated setting, which improves the stability of the scanning module during the scanning action, which is beneficial to increase the pitch field angle, and reduce the volume of the scanning module and the laser radar, thereby realizing the miniaturization of the radar.

[0054] like Figure 1 As shown, in some embodiments, the refractive optical element 800 has an exit surface and an incident surface, and the exit surface and the incident surface of the refractive optical element 800 are arranged to be inclined toward each other at one end thereof that is close to each other.

[0055] In these embodiments, the specific setting between the exit surface and the incident surface, that is, the ends close to each other are tilted toward each other, helps to achieve the desired beam path adjustment. That is, the light beam is incident on the refractive optical element 800 along a direction parallel to the first preset axis, and is refracted after passing through the refractive optical element 800, thereby changing the propagation path of the light beam. The tilted setting between the exit surface and the incident surface helps to achieve a specific angle of light beam steering, ensuring that the light beam can be correctly directed to the next component.

[0056] Exemplarily, the angle between the exit surface and the incident surface is 10°, 20°, 30°, 40°, etc., which is not specifically limited here.

[0057] like Figure 1 As shown, in some embodiments, the first driving element 600 includes a first driving motor, the main shaft of the first driving motor is set as a hollow shaft, the axis of the hollow shaft coincides with the rotation axis of the refractive optical element 800; wherein the refractive optical element 800 is set in the hollow shaft.

[0058] In these embodiments, the refractive drive motor is used to drive the refractive optical element 800 to rotate, such as a wedge mirror, to achieve precise control of the beam path. The main shaft of the refractive drive motor adopts a hollow shaft design, allowing other components or light beams to pass through its center. The axis of the hollow shaft completely coincides with the rotation axis of the refractive optical element 800, ensuring precise alignment between the two. The refractive optical element 800 is placed inside the hollow shaft, and the rotation axis of the refractive optical element 800, the first preset axis and the axis of the hollow shaft coincide, that is, this can ensure that the refractive optical element 800 maintains a stable center position during rotation.

[0059] Due to the presence of the hollow shaft, the light beam can enter and leave the refractive optical element 800 through the hollow shaft without being hindered by the motor or other mechanical components, thereby achieving a compact optical path layout.

[0060] Obviously, the hollow shaft makes the mechanical structure of the entire system more compact, saves space, and simplifies the optical path arrangement. The light beam can pass directly through the hollow shaft, avoiding contact with the motor housing or other mechanical parts, reducing unnecessary reflections or scattering, and improving the beam quality.

[0061] Furthermore, the hollow shaft provides better mechanical support, reduces vibration and shaking during rotation, and improves the overall stability of the system. Since the refractive optical element 800 is located inside the hollow shaft, it can be inspected or replaced without disassembling the motor, simplifying the maintenance process.

[0062] Exemplarily, the refraction drive motor is configured as a hollow shaft motor. Of course, this can also be achieved by replacing the main shaft of the refraction drive motor with a hollow shaft.

[0063] Exemplarily, the wedge-shaped mirror is a cylindrical mirror, and the two end faces of the wedge-shaped mirror are the incident face and the exit face respectively.

[0064] The wedge mirror will refract the light beam emitted from the inside on the outer surface, so that the laser will be refracted through the wedge mirror to form a deflection angle θ. As the wedge mirror rotates, the laser will produce a solid angle of 2θ, that is, a field of view of 2θ in the vertical direction.

[0065] Exemplarily, the angle θ is 10°, 20°, 30°, 40°, 50°, etc.

[0066] like Figure 1 As shown, in some embodiments, the slope of the exit surface is smaller than the slope of the incident surface.

[0067] In these embodiments, the slope of the exit surface of the refractive optical element 800 is smaller than the slope of the incident surface. This results in a certain slope difference between the incident surface and the exit surface of the refractive optical element 800 (such as a wedge mirror). The slope of the exit surface is smaller, while the slope of the incident surface is larger. This affects the refraction angle of the light beam when it passes through the refractive optical element 800, thereby changing the propagation direction and characteristics of the light beam.

[0068] Incident light beam: When the light beam is incident on the refractive optical element 800, the light beam will first undergo a significant refraction due to the large slope of the incident surface, changing its propagation direction. After the first refraction, the light beam propagates inside the element and eventually reaches the exit surface with a smaller slope.

[0069] Outgoing beam: Due to the small slope of the exit surface, the refraction angle of the light beam when leaving the element is relatively small, which helps maintain the directionality and energy concentration of the beam.

[0070] By adjusting the inclination of the incident and exit surfaces, the steering angle of the light beam can be more accurately controlled to ensure that the light beam propagates along the expected path. A smaller exit surface inclination helps reduce the additional divergence of the light beam at the exit and maintain a high energy density, which is especially important when propagating over long distances. Obviously, by optimizing the beam path, the system can obtain more accurate distance measurements and higher spatial resolution.

[0071] In some embodiments, the scanning module further includes a weight element, the refractive optical element 800 is formed with a thick end and a thin end, and the weight element is disposed on the thin end.

[0072] In these embodiments, the problem of uneven mass distribution caused by the asymmetry of the refractive optical element 800 (such as a wedge-shaped mirror) is addressed to ensure the mechanical balance and stability of the system.

[0073] Refractive optical element 800 (e.g. wedge mirror) is usually thicker at one end (thick end) and thinner at the other end (thin end). In order to balance the uneven mass distribution, a weight element is installed at the thin end. The main purpose of the weight element is to balance the mass distribution of the entire element by increasing the mass of the thin end, ensuring stability during rotation and reducing vibration.

[0074] When the refractive optical element 800 rotates, if it is not balanced, it will vibrate or shake due to uneven mass distribution, which will not only affect the precise control of the light beam, but also cause mechanical wear and shorten the service life. By adding a counterweight element at the thin end, the dynamic balance during rotation can be significantly improved, making the system run more smoothly and improving the accuracy and reliability of beam steering.

[0075] Illustratively, in this embodiment, the weight element is configured as a weight block.

[0076] like Figure 1 As shown, in some embodiments, the refractive optical element 800 includes a wedge-shaped mirror.

[0077] In these embodiments, the refractive optical element 800 uses a wedge mirror, which is a transparent optical element with an inclined surface that can be used to change the direction of a light beam without changing its focusing characteristics. The wedge mirror is composed of two parallel or non-parallel pieces of glass or other transparent materials, two of which are inclined, namely the incident surface and the exit surface. When the light beam passes through the wedge mirror, due to the existence of its inclined surface, the light beam will be deflected and the propagation direction will be changed. This deflection angle depends on the incident angle and the wedge angle of the wedge mirror.

[0078] Unlike prisms, wedge mirrors do not cause significant changes in the focus position of the light beam, which means that the beam path can be changed without destroying the imaging quality. Wedge mirrors can be used to deflect the transmitted light beam or to redirect the received return light beam, thus simplifying the optical path of the system.

[0079] In the emission stage in the scanning module: the light beam emitted by the laser 100 is collimated and first reflected by the second reflective optical element 400 and propagates in a direction parallel to the first preset axis. The light beam then enters the wedge mirror, and according to the angle setting of the wedge mirror, the light beam will be deflected at a specific angle to ensure that it is emitted to the target area along the predetermined path.

[0080] Receiving stage: The returning beam passes through the wedge mirror again and is redirected to ensure that it can accurately reach the subsequent optical components, such as focusing optical elements. This bidirectional operation capability makes the wedge mirror an indispensable part of the scanning module, which helps to achieve efficient beam management and precise target positioning.

[0081] Since the wedge mirror can change the beam path without affecting the image quality, it helps to design a more compact system layout. Compared with traditional rotating mirrors, the wedge mirror can achieve a wide range of beam steering through small angle adjustments, reducing the need for complex mechanical movements and improving the reliability and life of the system.

[0082] Exemplarily, the wedge-shaped mirror is trapezoidal. For the transmitting light path, the light beam is incident from the incident surface with a large slope and exits from the exit surface with a small slope. For the receiving light path, the returning light beam is incident from the exit surface with a small slope and exits from the incident surface with a large slope.

[0083] like Figure 2 and Figure 3 As shown, in some embodiments, the second driving element 1100 is a second driving motor. The main shaft of the second driving motor is arranged vertically. Exemplarily, the second driving motor is a servo motor, a stepper motor or a steering gear, etc.

[0084] like Figure 1 , Figure 2 and Figure 3 As shown, in some embodiments, the present application also provides a laser radar, which includes a scanning module, a turntable 300, a laser emitting module and a laser receiving module, the scanning module is a scanning module as described in any of the above embodiments; the laser emitting module is used to emit a light beam, and the laser receiving module is used to receive a return light beam, the first driving element 600, the laser emitting module and the laser receiving module are all arranged on the turntable 300, the turntable 300 and the first driving element 600 are all arranged on the second driving element 1100 of the scanning module, and the second driving element 1100 is used to drive the turntable 300 to rotate around the second preset axis.

[0085] In these embodiments, the laser radar combines an improved scanning module, a turntable 300, a laser transmitting module and a laser receiving module to provide a more efficient three-dimensional detection solution with a larger field of view.

[0086] As mentioned above, the scanning module includes two vertically arranged preset axes (the first preset axis is a horizontal axis, and the second preset axis is a vertical axis), a refractive optical element 800, a first driving element 600, and a second driving element 1100. This module is responsible for controlling the direction of the light beam to achieve a wide range of pitch and azimuth scanning.

[0087] The turntable 300 is used to carry the laser emitting module and the laser receiving module, and is installed on the second driving element 1100 together with the first driving element 600. The function of the turntable 300 is to ensure that all key components can rotate around the second preset axis together with the second driving element 1100.

[0088] For example, the axis of the turntable 300 coincides with the second preset axis. When the second driving element 1100 is a second driving motor, the main shaft of the second driving motor and the turntable 300 are coaxially arranged.

[0089] The laser emission module is located on the turntable 300 and is responsible for generating and emitting laser beams, which are directed to the target area after passing through the refractive optical element 800.

[0090] The laser receiving module is also located on the turntable 300 and is used to receive the light beam reflected from the target. The transmission path must be precisely aligned to ensure effective capture of the return signal.

[0091] The first driving element 600 drives the refractive optical element 800 to rotate around the horizontal axis to control the scanning angle of the light beam in the vertical direction. The second driving element 1100 drives the entire turntable 300 and the first driving element 600 to rotate around the vertical axis to achieve omnidirectional horizontal scanning.

[0092] The following workflow is also provided:

[0093] The light beam emitted by the laser emission module is first adjusted in direction by the refractive optical element 800 and then emitted to the target object. When the light beam encounters the detection object, it is reflected to form a return light beam, which passes through the refractive optical element 800 again and is finally captured by the laser receiving module.

[0094] By adjusting the actions of the first driving element 600 and the second driving element 1100 , a comprehensive scan of targets at different directions and heights can be achieved.

[0095] The unique dual-axis rotation mechanism, especially the large-angle scanning capability in the vertical direction, significantly improves the three-dimensional perception range of the LiDAR, allowing the device to obtain more detailed data in complex environments. The integrated design reduces the relative movement between mechanical components, improves the overall stability and response speed of the system, and ensures the accuracy and consistency of the measurement results. All key components are concentrated on the turntable 300, which not only simplifies the system architecture, but also promotes the miniaturization and lightweight of the equipment, making it easier to install and deploy.

[0096] like Figure 1 As shown, in some embodiments, the laser receiving module further includes:

[0097] N-level first reflecting optical elements 700, which are disposed on the turntable 300, and are used to receive and reflect N times the returning light beam refracted by the refractive optical element 800, and satisfy: N ≥ 1, where N is a positive integer;

[0098] At least one focusing optical element, which is disposed on the turntable 300, and in the propagation direction of the return light beam, at least one focusing optical element is disposed upstream or downstream of the at least one first reflecting optical element 700, and the focusing optical element is used to receive and focus the return light beam;

[0099] The detector 1000 is disposed on the turntable 300. In the propagation direction of the return light beam, the detector 1000 is located at the most downstream position. The detector 1000 is used to receive the return light beam.

[0100] In these embodiments, this improved laser receiving module further optimizes the processing flow of the return light beam by introducing multi-stage reflection optical elements and focusing optical elements, thereby improving the signal quality received by the detector 1000 and the overall performance of the system.

[0101] The multi-stage reflective optical element, i.e., the N-stage first reflective optical element 700, is disposed at a preset position on the turntable 300, and is used to receive and multiple-times reflect the return light beam after being refracted by the refractive optical element 800. Each reflection adjusts the direction of the return light beam to ensure that it can be accurately transmitted to the detector 1000 in the end.

[0102] For example, in this embodiment, N is 2, so that the return light path forms a U-shape or an L-shape, which is conducive to reducing the size of the scanning radar. Of course, in other embodiments, N can also be 1, 3, 4, 5, etc.

[0103] Obviously, this configuration allows the light beam to pass through multiple reflective surfaces during propagation, thereby achieving more precise directional control, and can extend the optical path in a limited space, which helps to improve resolution and signal-to-noise ratio, and is conducive to the miniaturization of lidar.

[0104] For example, in this embodiment, the return light path of the component is set to be U-shaped. Of course, in other embodiments, the return light path can also be set to be L-shaped, etc.

[0105] At least one focusing optical element, also mounted on the turntable 300, is located in the propagation path of the return beam, which may be upstream or downstream of some first reflective optical elements 700. The function of the focusing optical element is to refocus the scattered return beam into a fine light spot so that it can be better captured by the detector 1000.

[0106] The presence of the focusing optical element ensures that the light beam can maintain a high energy density even in a complex reflection path, reducing energy loss and enhancing the sensitivity of the detector 1000.

[0107] The detector 1000 is placed at the most downstream position of the turntable 300. As the last link of the receiving chain, it is responsible for finally capturing the return light beam after all reflections and focusing processes. The task of the detector 1000 is to convert the received optical signal into an electrical signal for use by the subsequent data processing system.

[0108] Exemplarily, there are multiple detectors 1000, such as 2, 3, 4, 5, 6 or 7, etc., and they are arranged in an array to increase the receiving area.

[0109] Obviously, the combination of the multi-stage first reflection optical element 700 and the focusing optical element ensures that the return light beam can be fully adjusted and optimized before reaching the detector 1000, thereby improving the received signal strength and clarity. Through multiple reflections and focusing, the return light beam can be more accurately aligned with the detector 1000, which not only increases the resolution of the system, but also enables more detailed distinction of target objects at different distances.

[0110] like Figure 1 As shown, in some embodiments, the scanning module also includes a laser 100, an M-level second reflecting optical element 400 and at least one collimating optical element, the laser 100 is used to emit a light beam; the M-level second reflecting optical element 400 is used to receive and reflect the light beam emitted by the laser 100 M times, so that the light beam propagates in a direction parallel to a first preset axis, and satisfies: M ≥ 1, M is a positive integer; in the propagation direction of the light beam, at least one collimating optical element is arranged upstream or downstream of at least one second reflecting optical element 400 to shrink the divergence angle of the light beam; and the laser 100 and the detector 1000 are respectively arranged on both sides of the first preset axis.

[0111] In these embodiments, the improved scanning module not only optimizes the emission path of the light beam, but also improves the quality and direction control accuracy of the light beam by introducing multi-stage reflection optical elements and collimation optical elements.

[0112] The laser 100 is responsible for generating and emitting an initial light beam. The laser 100 is arranged on one side of a first preset axis. The emitted light beam first undergoes a series of processing steps to ensure that it can propagate along a predetermined path and finally reach the target area in a direction parallel to the first preset axis. Exemplarily, the preset path is set as a U-shaped path. Alternatively, the preset path is set as an L-shaped path.

[0113] The M-level second reflective optical element 400 is used to receive and reflect the light beam emitted by the laser 100 multiple times, so that the light beam propagates in a direction parallel to the first preset axis. Each reflection adjusts the direction of the light beam to ensure that it can be accurately guided to the refractive optical element 800 or directly enter the next processing stage within a limited space. This design allows the light beam to pass through multiple reflective surfaces during propagation, thereby achieving more precise direction control, and can extend the optical path within a limited space, which helps to improve resolution and signal-to-noise ratio, and is also conducive to the miniaturization of the laser radar.

[0114] At least one collimating optical element is arranged on the beam propagation path, which may be upstream or downstream of some second reflecting optical elements 400. The function of the collimating optical element is to shrink the divergence angle of the beam, making the beam more concentrated and parallel. The presence of the collimating optical element ensures that the beam can still maintain a high energy density even in a complex reflection path, reduces energy loss, and enhances the detection distance and accuracy.

[0115] The collimated light beam will propagate in a direction parallel to the first preset axis, and then undergo further direction adjustment through the refractive optical element 800, and finally be emitted to the target object.

[0116] Furthermore, the laser 100 and the detector 1000 are respectively arranged on both sides of the first preset axis in the horizontal direction. This layout helps to reduce the mutual interference between the two and at the same time reduce the size of the radar.

[0117] like Figure 1 As shown, in some embodiments, the first reflective optical element 700 is a first reflector. In the propagation direction of the light beam, the first reflector is arranged upstream of the refractive optical element 800, and the first reflector has a light-transmitting hole 710, so that the light beam can pass through the light-transmitting hole 710 and enter the refractive optical element 800.

[0118] In these embodiments, the first reflective optical element 700 is selected as the first reflector, and a key feature is introduced into the propagation path of the light beam, namely, the light-transmitting hole 710. This design optimizes the receiving and refraction process of the light beam, and ensures the smoothness and efficiency of the light path.

[0119] The first reflector of the first stage is arranged upstream of the refractive optical element 800: this means that the light beam will first pass through this reflector before reaching the refractive optical element 800. The function of the first reflector of the first stage is to receive the return light beam from the refractive optical element 800 and reflect it to a predetermined direction.

[0120] A light-transmitting hole 710 is provided on the first reflector of the first stage, allowing part or all of the light beam to pass directly without being reflected. In other words, the emitted light beam can pass through the light-transmitting hole 710 and enter the refractive optical element 800 without being reflected first, thereby paving the way for the subsequent reflection of the returning light beam.

[0121] For ease of understanding, the workflow is provided as follows:

[0122] After the light beam emitted by the laser 100 reaches the first reflector of the first stage, at least part of the light beam avoids reflection through the light-transmitting hole 710 and directly enters the refractive optical element 800. The refractive optical element 800 adjusts the direction of the incident light beam so that it is emitted at a set angle and continues its detection task.

[0123] After passing through the refractive optical element 800 , the returning light beam is reflected by the first reflector of the first stage to adjust its direction so that the returning light beam can be received by the detector 1000 .

[0124] It should be noted that the reflected return light beam is parallel to the outgoing light beam, and follows part of the same path, passes through the first-stage first reflecting optical element 700 and the focusing optical element, and finally hits the detector 1000. Since the outgoing light beam is small and the area of ​​the light-transmitting hole 710 is small, except for a small amount of return light speed passing through the light-transmitting hole 710, the rest of the return light beam is reflected by the first-stage first reflecting optical element 700 and propagates to the detector 1000. Among them, the proportion of this part of the return light beam passing through the light-transmitting hole 710 to the total return light beam is limited, and does not affect the overall detection effect.

[0125] like Figure 1 As shown, in some embodiments, the second reflecting optical element 400 includes a second reflecting mirror. Of course, in other embodiments, the second reflecting optical element 400 can also be configured as a plane reflecting mirror, a reflecting prism, a multi-faceted reflecting prism, etc.

[0126] In some embodiments, the focusing optical element includes a receiving lens 900. The main function of the receiving lens 900 is to effectively focus the returning light beam onto the detector 1000, thereby improving the signal-to-noise ratio and measurement accuracy of the system.

[0127] Furthermore, there is an additional advantage of using the receiving lens 900: the receiving lens 900 can achieve efficient beam management in a compact space, simplifying the overall optical path design of the system. Compared with other complex focusing mechanisms, the design of the receiving lens 900 is simpler and more reliable, reducing the use of mechanical components and improving the stability of the system. Certain types of receiving lenses 900 (such as aspherical lenses) can support a larger field of view, which is suitable for wide-area scanning applications.

[0128] In some embodiments, the collimating optical element includes a collimating mirror.

[0129] In the emission stage in the scanning module: the divergent light beam emitted by the laser 100 first passes through the collimator, which converts the divergent light beam into a parallel light beam, ensuring that the light beam maintains a high energy density and directionality during propagation.

[0130] Obviously, by reducing the divergence angle of the light beam, the collimator can ensure that the light beam can still maintain a high energy density when propagating over a long distance, thereby improving the measurement accuracy of the system. The collimated light beam can maintain a strong signal strength at a longer distance, extending the detection range of the system. The collimator helps control the spot size reaching the target surface, ensuring measurement consistency at different distances. In addition, by improving the directionality of the light beam, the interference of other light sources in the environment is reduced, and the signal-to-noise ratio is improved.

[0131] For example, in the present application, there are two collimators, and the two collimators are respectively a first collimator 200 and a second collimator 500. The laser 100 is an edge-emitting laser 100. The first-stage collimator can constrain the laser beam with a large divergence angle emitted by the fast axis of the edge-emitting laser 100 to a laser beam with a smaller divergence angle. Of course, if the laser 100 is a surface-emitting laser 100, then the first-stage collimator is a spherical lens.

[0132] The second collimator lens constrains the laser beam with a large divergence angle emitted by the fast axis of the edge-emitting laser 100 into a laser beam with a smaller divergence angle. Of course, if the laser 100 is a surface-emitting laser 100, the second collimator lens is a spherical lens.

[0133] In the laser emission optical path, the first-stage collimator and the second-stage collimator can be appropriately placed with reflectors according to actual conditions, mainly the need for light path folding. For example, in this implementation, a second reflective optical element 400 is placed between the first-stage collimator and the second-stage collimator to fold the light path and reduce the system volume.

[0134] In summary, the laser inside the device is collimated, and the laser does not diverge inside the device, which makes it easier to achieve multi-line lasers and small laser divergence angles, while keeping the overall structure small. In addition, the overall structure is compact, achieving a large scanning field of view while maintaining a small volume.

[0135] In addition, the following tests are provided:

[0136] like Figure 4 As shown, in test 1, when the speed of the first drive motor is 6000 r / min and the speed of the second drive motor is 600 r / min, the scanning point cloud trajectory formed by the laser 100 in a single frame.

[0137] like Figure 5 As shown, in Experiment 2, when the speed of the first driving motor is 6000 r / min and the speed of the second driving motor is 600 r / min, the scanning point cloud trajectory formed by the laser 100 line in a single frame, wherein the angles between the light emitted by the laser 100 and the optical axis of the wedge mirror are 10°, 3°, -3°, and -10°, respectively.

[0138] like Figure 6 As shown, in test three, when the speed of the first drive motor is 6000r / min and the speed of the second drive motor is 600r / min, the scanning point cloud trajectory formed by the laser 100 line in a single frame, wherein the angles of the light emitted by the laser 100 and the optical axis of the wedge mirror are 12°, 8°, 4°, 0°, -4°, -8°, and -12°, respectively.

[0139] In all examples shown and described herein, any specific values ​​should be interpreted as merely exemplary and not as limiting, and thus other examples of the exemplary embodiments may have different values.

[0140] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0141] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application.

Claims

1. A scanning module, characterized in that: The scanning module has a first preset axis and a second preset axis which are arranged perpendicular to each other, and comprises a refractive optical element (800), a first driving element (600) and a second driving element (1100); the refractive optical element (800) is arranged on the first driving element (600); the first driving element (600) is used to drive the refractive optical element (800) to rotate around the first preset axis; the refractive optical element (800) is used to receive and refract a light beam incident along a direction parallel to the first preset axis; the first driving element (600) is connected to the second driving element (1100); the second driving element (1100) is used to drive the first driving element (600) to rotate around the second preset axis.

2. The scanning module according to claim 1, characterized in that: The refractive optical element (800) has an exit surface and an incident surface, and the exit surface and the incident surface of the refractive optical element (800) are arranged at ends close to each other and are inclined toward each other.

3. The scanning module according to claim 2, characterized in that: The first drive element (600) comprises a first drive motor, the main shaft of the first drive motor being arranged as a hollow shaft, the axis of the hollow shaft being coincident with the rotation axis of the refractive optical element (800); wherein the refractive optical element (800) is arranged in the hollow shaft.

4. The scanning module according to claim 3, characterized in that: The slope of the exit surface is smaller than the slope of the incident surface.

5. The scanning module according to claim 4, characterized in that: The scanning module also includes a weight element, the refractive optical element (800) is formed with a thick end and a thin end, and the weight element is arranged on the thin end.

6. The scanning module according to claim 1, characterized in that: The refractive optical element (800) comprises a wedge-shaped mirror.

7. A laser radar, characterized in that: The laser radar comprises: A scanning module, wherein the scanning module is the scanning module according to any one of claims 1 to 6; A turntable (300), a laser emitting module and a laser receiving module, wherein the laser emitting module is used to emit a light beam, and the laser receiving module is used to receive a return light beam, the first driving element (600), the laser emitting module and the laser receiving module are all arranged on the turntable (300), and the turntable (300) is arranged on the second driving element (1100) of the scanning module, and the second driving element (1100) is used to drive the turntable (300) to rotate around the second preset axis.

8. The laser radar according to claim 7, characterized in that: The laser receiving module also includes: N-stage first reflecting optical elements (700), the N-stage first reflecting optical elements (700) being arranged on the turntable (300), the N-stage first reflecting optical elements (700) being used to receive and reflect N times the return light beam refracted by the refractive optical element (800), and satisfying: N≥1, where N is a positive integer; at least one focusing optical element, the focusing optical element being arranged on the turntable (300), wherein in the propagation direction of the return light beam, at least one focusing optical element is arranged upstream or downstream of at least one of the first reflecting optical elements (700), and the focusing optical element is used to receive and focus the return light beam; A detector (1000), the detector (1000) being arranged on the turntable (300), the detector (1000) being located at the most downstream position in the propagation direction of the return light beam, and the detector (1000) being used to receive the return light beam.

9. The laser radar according to claim 8, characterized in that: The scanning module also includes: A laser (100), the laser (100) being used to emit the light beam; M-level second reflecting optical elements (400), the M-level second reflecting optical elements (400) being used to receive and reflect M times the light beam emitted by the laser (100), so that the light beam propagates in a direction parallel to the first preset axis, and satisfying: M≥1, M is a positive integer; At least one collimating optical element is provided upstream or downstream of at least one of the second reflecting optical elements (400) in the propagation direction of the light beam to shrink the divergence angle of the light beam; and the laser (100) and the detector (1000) are respectively provided on both sides of the first preset axis.

10. The laser radar according to claim 9, characterized in that: The first reflective optical element (700) is a first reflector, and in the propagation direction of the light beam, the first reflector of the first stage is arranged upstream of the refractive optical element (800), and the first reflector of the first stage has a light-transmitting hole (710), so that the light beam can pass through the light-transmitting hole (710) and enter the refractive optical element (800); And / or, the second reflective optical element (400) comprises a second reflector; and / or, the focusing optical element comprises a receiving lens (900); And / or, the collimating optical element comprises a collimating mirror.

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