Lidar

Abstract

The present disclosure provides a laser radar. The laser radar comprises an optical-mechanical structure, which moves around a first rotation axis. The optical-mechanical structure comprises a transceiver assembly and a mirror. The transceiver assembly comprises a laser, a transmitting optical component, a receiving optical component and a detector, and a transmitting optical axis and a receiving optical axis are not collinear. The mirror moves around a second rotation axis, and an included angle between the second rotation axis and the first rotation axis is greater than 0°. The scheme provided by the present disclosure can make a single channel of the laser radar sufficient to realize a detection field of view greater than a half sphere, low cost, and can increase a receiving aperture, suppress crosstalk between transmitting and receiving, and improve the performance of the laser radar.

Description

Technical Field

[0001] This disclosure relates to the field of laser detection, and in particular to a lidar. Background Technology

[0002] LiDAR (Light Detection and Ranging) is a radar system that uses laser beams to detect the position, velocity, and other characteristics of targets. It is an advanced detection method that combines laser technology with photoelectric detection technology. Due to its advantages such as high resolution, good concealment, strong resistance to active interference, good low-altitude detection performance, small size, and light weight, LiDAR is widely used in fields such as autonomous driving, drones, intelligent robots, and resource exploration.

[0003] To achieve comprehensive environmental detection, a larger detection field of view is a key pursuit in the field of lidar. Some lidar systems employ more lasers and detectors to achieve this, resulting in higher costs. How to achieve a larger detection field of view for lidar at a lower cost is a technical problem that needs to be solved in this field. Summary of the Invention

[0004] The problem addressed in this disclosure is how to achieve a larger detection field of view for lidar at a low cost.

[0005] To address the aforementioned issues, this disclosure provides a lidar, comprising: an optomechanical structure that moves around a first axis; the optomechanical structure includes: a transceiver assembly and a reflector; the transceiver assembly includes: a laser, a transmitting optics element, a receiving optics element, and a detector, wherein the transmitting optical axis and the receiving optical axis are not collinear; and the reflector moves around a second axis, wherein the angle between the second axis and the first axis is greater than 0°.

[0006] Optionally, the detection beam emitted by the laser passes sequentially through the emitting optics and the reflector before exiting into the environment; the detection beam is reflected by an object to form an echo; the echo passes sequentially through the reflector and the receiving optics before entering the detector.

[0007] Optionally, the second rotating shaft is perpendicular to the first rotating shaft.

[0008] Optionally, the angle between the second rotating shaft and the reflecting surface of the mirror is 45°.

[0009] Optionally, the transmitting optical axis and the receiving optical axis are parallel to each other.

[0010] Optionally, the second rotating axis, the transmitting optical axis, and the receiving optical axis are coplanar.

[0011] Optionally, the second rotating shaft is located between the transmitting optical axis and the receiving optical axis.

[0012] Optionally, the second rotating shaft is close to the transmitting optical axis and the second rotating shaft is far away from the receiving optical axis.

[0013] Optionally, the size of the probe beam spot on the reflector is not larger than the size of the echo spot on the reflector.

[0014] Optionally, the first rotating axis is perpendicular to the plane containing the transmitting optical axis and the receiving optical axis.

[0015] Optionally, the transceiver assembly further includes a transceiver circuit board, which is disposed on one end of the transmitting optics and the receiving optics away from the reflector.

[0016] Optionally, the focal plane of the transmitting optics and the focal plane of the receiving optics are coplanar; the laser and the detector are disposed on the same transceiver circuit board.

[0017] Optionally, it further includes: a mounting bracket that moves around the first rotating axis; the transceiver assembly that is fixedly connected to the mounting bracket; and a reflector that is connected to the mounting bracket and can move relative to the mounting bracket.

[0018] Optionally, it further includes: a mounting bracket that moves around the first rotating axis and the second rotating axis; the transceiver assembly that is fixedly connected to the mounting bracket; and the reflector that is fixedly connected to the mounting bracket.

[0019] Optionally, the optomechanical structure moves about the first axis at a first frequency, and the reflector moves about the second axis at a second frequency; wherein the first frequency is greater than the second frequency.

[0020] Optionally, the transceiver assembly includes multiple lasers.

[0021] Optionally, the optomechanical structure moves around the first rotation axis to form a first field of view; the reflector rotates around the second rotation axis to form a second field of view, wherein the maximum field of view of the first field of view is 360°, and the maximum field of view of the second field of view is greater than 180°.

[0022] Compared with the prior art, the technical solution disclosed herein has the following advantages:

[0023] In the present technical solution, the transmitting optical axis and the receiving optical axis of the transceiver assembly are not collinear. The transceiver assembly adopts a side-axis optical path, which allows the lidar to achieve a detection field of view larger than a hemisphere with a single channel. This results in low cost, increased receiving aperture, suppression of crosstalk between transmitting and receiving, and improved lidar performance.

[0024] In this optional embodiment, the distance between the second rotating axis and the transmitting optical axis is no greater than the distance between the second rotating axis and the receiving optical axis; the spot size of the probe beam on the reflector is no greater than the spot size of the echo on the reflector. The second rotating axis being closer to the transmitting optical axis allows for a larger spot size of the echo on the reflector, effectively increasing the receiving aperture and improving detection efficiency. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of this disclosure or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort. The drawings are used to provide a further understanding of this disclosure and constitute a part of the specification. They are used together with the embodiments of this disclosure to explain this disclosure and do not constitute a limitation of this disclosure.

[0026] Figure 1 A schematic diagram of the structure of a lidar provided in some embodiments of this disclosure is shown;

[0027] Figure 2 A top view of a lidar structure provided in some embodiments of this disclosure is shown;

[0028] Figure 3 A top view of another lidar structure provided in some embodiments of this disclosure is shown;

[0029] Figure 4 A top view of another lidar structure provided in some embodiments of this disclosure is shown;

[0030] Figure 5 A schematic diagram of another lidar provided in some embodiments of this disclosure is shown;

[0031] Figure 6 A schematic diagram of a scanning path for a lidar provided in some embodiments is shown;

[0032] Figure 7 A schematic diagram of another scanning path for the lidar provided in some embodiments of this disclosure is shown;

[0033] Figure 8 A schematic diagram of another scanning path for the lidar provided in some embodiments of this disclosure is shown;

[0034] Figure 9 A schematic diagram of another scanning path for the lidar provided in some embodiments of this disclosure is shown. Detailed Implementation

[0035] In the following description, only certain exemplary embodiments are shown. As those skilled in the art will recognize, the described embodiments can be modified in various ways without departing from the spirit or scope of this disclosure. Therefore, the drawings and description are to be considered exemplary in nature and not restrictive.

[0036] In the description of this disclosure, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing this disclosure and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this disclosure. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more features. In the description of this disclosure, "a plurality of" means two or more, unless otherwise explicitly specified.

[0037] In the description of this disclosure, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linkage" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections, electrical connections, or connections that allow for communication; they can refer to direct connections or indirect connections through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this disclosure according to the specific circumstances.

[0038] In this disclosure, unless otherwise expressly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0039] The following disclosure provides numerous different embodiments or examples for implementing various structures of this disclosure. To simplify the disclosure, specific examples of components and arrangements are described below. These are merely examples and are not intended to limit the scope of this disclosure. Furthermore, reference numerals and / or letters may be repeated in different examples; such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed. In addition, various specific examples of processes and materials are provided in this disclosure, but those skilled in the art will recognize the application of other processes and / or the use of other materials.

[0040] To address the existing technical problems, this disclosure provides a lidar. The lidar includes an optomechanical structure that moves about a first axis. The optomechanical structure includes a transceiver assembly and a mirror. The transceiver assembly includes a laser, a transmitting optics component, a receiving optics component, and a detector. The transmitting optical axis and the receiving optical axis are not collinear. The mirror moves about a second axis. The angle between the second axis and the first axis is greater than 0°.

[0041] In this disclosed technical solution, the transmitting and receiving optical axes of the transceiver components are not collinear, and the transceiver components adopt a side-axis optical path. This allows the lidar to achieve a detection field of view larger than a hemisphere with a single channel, resulting in low cost. Furthermore, it can increase the receiving aperture, suppress crosstalk between the transmitter and receiver, and improve the performance of the lidar.

[0042] To make the above-mentioned objects, features and advantages of this disclosure more apparent and understandable, the embodiments of this disclosure will be described in detail below with reference to the accompanying drawings.

[0043] Figure 1 A schematic diagram of the structure of a lidar provided in some embodiments of this disclosure is shown.

[0044] The lidar includes an optomechanical structure 101. The optomechanical structure 101 is movable about a first rotation axis 111. The optomechanical structure 101 includes a transceiver assembly 110 and a reflector 120. The transceiver assembly 110 includes a laser, transmitting optics, receiving optics, and a detector. The transmitting optical axis txa and the receiving optical axis rxa are not collinear. The reflector 120 is movable about a second rotation axis 121. The angle between the second rotation axis 121 and the first rotation axis 111 is greater than 0°.

[0045] The optomechanical structure 101 can transmit and receive optical signals. The optomechanical structure 101 can move around a first rotation axis 111. The entire optomechanical structure 101 can move around the first rotation axis 111, and all structures and components within the optomechanical structure 101 can move around the first rotation axis 111. As the optomechanical structure 101 moves around the first rotation axis 111, the direction in which it transmits and receives optical signals also moves around the first rotation axis 111 to form a directional field of view.

[0046] In some embodiments, the optomechanical structure 101 can rotate around the first rotation axis 111. For example, the optomechanical structure 101 can rotate 360° unidirectionally around the first rotation axis 111. With the optomechanical structure 101 rotating 360° unidirectionally around the first rotation axis 111, the direction in which the optomechanical structure 101 emits and receives optical signals also rotates 360° unidirectionally around the first rotation axis 111, allowing the lidar to scan a 360° field of view. Alternatively, the optomechanical structure 101 can oscillate around the first rotation axis 111. For example, the optomechanical structure 101 can oscillate back and forth around the first rotation axis 111 within a preset angle range. With the optomechanical structure 101 oscillating back and forth around the first rotation axis 111 within the preset angle range, the direction in which the optomechanical structure 101 emits and receives optical signals also oscillates around the first rotation axis 111 within the preset angle range, allowing the lidar to scan the field of view within the preset angle range reciprocally. The preset angle range is, for example, -60° to +60°, or -45° to +45°, etc.

[0047] In some embodiments, the lidar may further include a mounting bracket 130. The mounting bracket 130 is movable about a first pivot axis 111. The optomechanical structure 101 may be connected to the mounting bracket 130. The optomechanical structure 101 as a whole can move with the mounting bracket 130 about the first pivot axis 111.

[0048] like Figure 1 In some embodiments shown, the mounting bracket 130 has a platform that is substantially perpendicular to the first pivot 111. At least a portion of the optomechanical structure 101 can be fixedly connected to the platform of the mounting bracket 130. The statement that the platform is substantially perpendicular to the first pivot 111 means that the first pivot 111 is perpendicular to the platform, or that the angle between the first pivot 111 and the platform is close to 90°.

[0049] In some embodiments, the first rotating axis 111 may be perpendicular to the horizontal plane. The movement of the optomechanical structure 101 around the first rotating axis 111 allows the lidar to scan a horizontal field of view. For example, when the optomechanical structure 101 rotates 360° around the first rotating axis 111, the lidar can scan a 360° horizontal field of view. For instance, if the first rotating axis 111 is perpendicular to the platform of the mounting bracket 130, and the platform of the mounting bracket 130 is parallel to the horizontal plane, the assembly and adjustment difficulty of the lidar can be effectively reduced.

[0050] like Figure 1 As shown, the optomechanical structure 101 includes a transceiver assembly 110 and a reflector 120. The transceiver assembly 110 can transmit and receive optical signals. The reflector 120 can change the transmission direction of light incident upon it.

[0051] In some embodiments, the lidar includes a mounting bracket 130 that moves about a first pivot axis 111, and a transceiver assembly 110 can be fixedly connected to the mounting bracket 130. The transceiver assembly 110 can move with the mounting bracket 130 about the first pivot axis 111. Figure 1 As shown, the transceiver assembly 110 can be fixed to the platform of the mounting bracket 130. For example, the transceiver assembly and the mounting bracket can be fixedly connected by means of adhesive bonding, fasteners, etc.

[0052] The transceiver assembly 110 includes a laser (not shown), a transmitting optics tx, a receiving optics rx, and a detector (not shown). The laser generates an optical signal. The detector receives the echo.

[0053] In some implementations, the laser emitter may include a laser emitting circuit, a vertical-cavity surface-emitting laser (VCSEL), an edge-emitting laser (EEL), a distributed feedback laser (DFB), a fiber laser, or a similar device.

[0054] In some implementations, the detector may include a photodetector circuit, a single-photon avalanche diode (SPAD), an avalanche photodiode (APD), a silicon photomultiplier (SiPM), or a similar device.

[0055] The transceiver assembly 110 includes at least one laser. For example... Figure 1 In some embodiments shown, the transceiver assembly 110 includes one laser. In some embodiments, the transceiver assembly may include two or more lasers.

[0056] The transmitting optics (tx) can transmit and shape the optical signal generated by the laser. Optionally, the transmitting optics may include a single optical lens or an optical lens group consisting of multiple optical lenses.

[0057] The receiving optics (rx) can transmit the echo and converge it to the detector. Optionally, the receiving optics may include a single optical lens or an optical lens group consisting of multiple optical lenses.

[0058] The transmitting optics tx and the receiving optics rx are arranged adjacent to each other. For example, the transmitting optics tx and the receiving optics rx can be arranged horizontally adjacent to each other. Optionally, the transmitting optics tx and the receiving optics rx can be arranged on the same lens mount or separately on different lens mounts. An optical isolator is provided between the transmitting optics tx and the receiving optics rx to avoid optical crosstalk between the laser and the detector.

[0059] The optical axis of the transmitting optics is the transmitting optical axis txa. The optical axis of the receiving optics is the receiving optical axis rxa. The transmitting optical axis txa and the receiving optical axis rxa are not collinear. For example, the line containing the transmitting optical axis txa intersects the line containing the receiving optical axis rxa. For example, the transmitting optical axis txa and the receiving optical axis rxa are parallel to each other and have a certain distance offset.

[0060] In some embodiments, the transmitting module may include a transmitting optics element tx and a laser. The transmitting optical axis txa is the axis of the transmitting module. The receiving module may include a receiving optics element rx and a detector. The receiving optical axis rxa is the axis of the receiving module.

[0061] The transmitting optical axis txa and the receiving optical axis rxa are not collinear. The optical path of the transceiver assembly 110 is a side-axis optical path. By setting the optical path of the transceiver assembly 110 as a side-axis optical path, the laser and detector are not blocked along the optical path, and the entire aperture of the receiving optics rx can be used to receive optical signals. The aperture of the receiving optics rx can be larger. Moreover, in the transceiver assembly 110, the transmitting optics and the receiving optics are independent of each other, and the transmitting optical path and the receiving optical path do not affect each other. Crosstalk between the probe light and the echo can be reduced without additional light-blocking design.

[0062] In some embodiments of this disclosure, the transceiver assembly 110 may further include a transceiver circuit board 112. The transceiver circuit board 112 may be disposed on one end of the transmitting optics tx and the receiving optics rx away from the reflector 120. The transceiver circuit board 112 can fix the electronic components in the transceiver assembly 110 and electrically connect them to external circuits. The transceiver circuit board 112 can be a printed circuit board or other circuit boards. The transceiver circuit board includes at least one circuit board. The transmitting optical axis txa and the receiving optical axis rxa are not collinear, allowing for more flexible arrangement of the laser and detector; for example, the laser and detector can be disposed on the same circuit board. This enables the laser and detector to be integrated on a single board, reducing the difficulty of assembly and adjustment. In other embodiments of this disclosure, the laser and detector may also be disposed on two separate circuit boards. The two separate circuit boards may be placed in the same or different locations.

[0063] In some embodiments, the focal plane of the transmitting optics tx and the focal plane of the receiving optics rx can be coplanar. The laser and detector can be mounted on the same transceiver circuit board, which can be located on the focal plane of the transmitting optics tx and the receiving optics rx. In the transceiver assembly 110 of the off-axis optical path, the transmitting optics tx and the receiving optics rx are independent of each other and do not affect each other; the focal planes of the transmitting optics tx and the receiving optics rx do not affect each other. When the focal planes of the transmitting optics tx and the receiving optics rx are coplanar, the transceiver circuit board 112 can be located at the focal plane position of both, which, while ensuring detection performance, enables co-platform integration of the laser and detector, reducing assembly and adjustment difficulty and cost.

[0064] In some embodiments of this disclosure, the transmitting optical axis txa and the receiving optical axis rxa can be parallel to each other. Parallelism of the transmitting optical axis txa and the receiving optical axis rxa means that the transmitting optical axis txa and the receiving optical axis rxa can be coplanar and substantially parallel, and the angle between the transmitting optical axis txa and the receiving optical axis rxa can be 0°; or, the transmitting optical axis txa and the receiving optical axis rxa can be coplanar and the angle between them can be less than 5°.

[0065] In some embodiments, the transmitting optical axis txa and the receiving optical axis rxa can both be substantially perpendicular to the first rotation axis 111. For example, the transmitting optical axis txa and the receiving optical axis rxa may not be coplanar, and the angles between each of the transmitting optical axis txa and the receiving optical axis rxa and the first rotation axis 111 may be 90° or close to 90°; or the plane in which the transmitting optical axis txa and the receiving optical axis rxa coexist is substantially perpendicular to the first rotation axis 111. For example, the transmitting optical axis txa and the receiving optical axis rxa are coplanar, and the angle between the plane in which they coexist and the first rotation axis 111 is 90° or close to 90°.

[0066] In some embodiments, the transceiver assembly 110 may be fixed to the platform of the mounting bracket 130. The transmitting optical axis txa and the receiving optical axis rxa are both substantially parallel to the platform of the mounting bracket 130, or the plane where the transmitting optical axis txa and the receiving optical axis rxa coexist is substantially parallel to the platform of the mounting bracket 130. For example, the platform of the mounting bracket 130 may be parallel to a horizontal plane, and the transmitting optical axis txa and the receiving optical axis rxa may both be substantially parallel to a horizontal plane, or the plane where the transmitting optical axis txa and the receiving optical axis rxa coexist is substantially parallel to a horizontal plane.

[0067] In some embodiments, the laser and detector in transceiver assembly 110 are fixed to transceiver circuit board 112. The transmitting optical axis txa and the receiving optical axis rxa are both substantially perpendicular to the surface of transceiver circuit board 112.

[0068] Continue to refer to Figure 1The optomechanical structure 101 also includes a reflector 120. The reflector 120 can reflect the optical signals emitted by the transceiver component 110 into the environment, and can also reflect the echo back to the transceiver component 110.

[0069] The reflector 120 can move around the second axis 121. As the reflector 120 moves around the second axis 121, the direction in which the light signal reflected by the reflector 120 exits into the environment and the direction in which the echo incident on the reflector 120 moves around the second axis 121 to form a field of view in another direction.

[0070] For example, the reflector 120 can rotate 360° unidirectionally around the second axis 121. When the reflector 120 rotates 360° unidirectionally around the second axis 121, the direction of the reflected light signal emitted into the environment and the direction of the echo incident on the reflector 120 will also rotate 360° unidirectionally around the second axis 121. Alternatively, the reflector 120 can oscillate back and forth around the second axis 121. When the reflector 120 oscillates back and forth around the second axis 121, the direction of the reflected light signal emitted into the environment and the direction of the echo incident on the reflector 120 will also oscillate back and forth around the second axis 121 within a preset angle range. The preset angle range could be, for example, -180° to 180°, -120° to 120°, -100° to 100°, or -80° to 80°, etc.

[0071] In some embodiments, the reflector 120 can be directly or indirectly connected to the mounting bracket 130 via a reflector mounting bracket. For example, the bottom of the reflector mounting bracket can be fixedly connected to the platform of the mounting bracket 130. The reflector 120 can move relative to the reflector mounting bracket about a second pivot 121. The reflector mounting bracket can be equipped with a drive motor, which can drive the reflector 120 to move.

[0072] In some embodiments of this disclosure, the detection beam emitted by the laser passes sequentially through the emitting optics and the reflector 120 before exiting into the environment. The detection beam is reflected by an object to form an echo. The echo passes sequentially through the reflector 120 and the receiving optics before entering the detector.

[0073] Both the detection beam and the echo are transmitted through the reflector 120. When the reflector 120 moves around the second axis 121, it reflects the detection beam to different locations within the field of view and receives echoes from those locations. With the movement of the reflector 120, the lidar can scan and detect a certain range of the field of view. The optomechanical structure 101 moves around the first axis 111, and the reflector 120 moves around the second axis 121, forming two sets of rotational axes that create two separate fields of view in different directions. By using these two sets of axes, a larger detection field of view can be achieved with a smaller number of lasers and detectors.

[0074] The second rotating shaft 121 forms a preset angle with the first rotating shaft 111, and the angle between the second rotating shaft 121 and the first rotating shaft 111 is greater than 0°. In some embodiments, the second rotating shaft 121 and the first rotating shaft 111 are tilted relative to each other. The tilt angle can be determined according to the scanning field of view of the lidar. In some embodiments, the second rotating shaft 121 and the first rotating shaft 111 are perpendicular to each other. Figure 1 In some embodiments shown, the first pivot 111 is perpendicular to the platform of the mounting bracket 130; the second pivot 121 is parallel to the platform of the mounting bracket 130. For example, the platform of the mounting bracket 130 is parallel to the horizontal plane, and the second pivot 121 is parallel to the horizontal plane.

[0075] In some embodiments, the angle between the second rotating axis 121 and the reflecting surface of the mirror 120 can be 45°. Setting the angle between the reflecting surface of the mirror 120 and the second rotating axis 121 to 45° makes the optical axes of the upstream and downstream optical paths of the mirror 121 perpendicular to each other, which can effectively simplify the optical path structure. When the laser emits a probe beam in the horizontal direction, the mirror 120 can reflect the probe beam incident on it horizontally in a vertical plane. As the mirror 120 moves around the second rotating axis 121, the lidar can scan the vertical field of view. As the optomechanical structure 101 moves around the first rotating axis 111, the lidar can scan the horizontal field of view. When the mirror 120 and the optomechanical structure 101 move simultaneously, the lidar can achieve a three-dimensional field of view scan.

[0076] like Figure 1 In some embodiments shown, the second rotating shaft 121 is parallel to the platform of the mounting bracket 130; the angle between the reflective surface of the reflector 120 and the platform of the mounting bracket 130 is 45°, and the normal of the reflective surface faces away from the platform of the mounting bracket 130.

[0077] By moving the reflector 120, the lidar can achieve field-of-view scanning in a non-vertical plane. When the reflector 120 and the optomechanical structure 101 move simultaneously, both vertical and horizontal field-of-view scanning can be achieved. When the rotation angle of the optomechanical structure 101 is 360° and the rotation angle of the reflector 120 is greater than or equal to 180°, the lidar can achieve hemispherical or larger-than-hemisphere field-of-view detection.

[0078] In some embodiments, the angle between the second rotating shaft 121 and the reflecting surface of the reflector 120 can be any angle between 20° and 70°. For example, the angle can be 30°, 50°, 60°, etc. When the reflector 120 and the optomechanical structure 101 move simultaneously, scanning of both the vertical and horizontal fields of view can be achieved. When the rotation angle of the optomechanical structure 101 is 360° and the rotation angle of the reflector 120 is greater than or equal to 180°, the lidar can achieve non-complete hemispherical field of view detection, and can also achieve higher scanning line density and higher point cloud resolution in the field of view area.

[0079] Depending on the application requirements of the lidar and its installation location on the carrier, the specific value of the angle between the second rotating shaft 121 and the reflecting surface of the reflector 120 can be set. Optionally, the angle between the second rotating shaft 121 and the reflecting surface of the reflector 120 can be a fixed value, or it can be adjusted by a driving device. By changing the angle between the second rotating shaft 121 and the reflecting surface of the reflector 120, the field of view and point cloud density of the lidar can be adjusted.

[0080] In some embodiments, the second rotating axis 121, the transmitting optical axis txa, and the receiving optical axis rxa can be coplanar, and the second rotating axis 121 can be located in the plane where the transmitting optical axis txa and the receiving optical axis rxa coexist. For example... Figure 1 As shown, the second rotating shaft 121, the transmitting optical axis txa, and the receiving optical axis rxa are all parallel to the platform of the mounting bracket 130.

[0081] In some embodiments, the second rotating shaft 121 is located between the transmitting optical axis txa and the receiving optical axis rxa. Figure 2 A top-view structural schematic diagram of a lidar provided in some embodiments of this disclosure is shown. For example... Figure 2 As shown, the transmitting optics tx and the receiving optics rx are located on opposite sides of the second rotating shaft 121. Optionally, the second rotating shaft 121 can be parallel to the transmitting optical axis txa and the receiving optical axis rxa. Alternatively, the second rotating shaft 121 can be at an angle to the transmitting optical axis txa and the receiving optical axis rxa. For example, the second rotating shaft 121 intersects the lines containing the transmitting optical axis txa and the receiving optical axis rxa at a single point.

[0082] The second rotating shaft 121 is located midway between the transmitting optical axis txa and the receiving optical axis rxa. In some embodiments, the angle between the transmitting optical axis txa and the receiving optical axis rxa is 0°, and the distance between the second rotating shaft 121 and the transmitting optical axis txa is equal to the distance between the second rotating shaft 121 and the receiving optical axis rxa. In some embodiments, there may be an angle between the transmitting optical axis txa and the receiving optical axis rxa, and the angle between the second rotating shaft 121 and the transmitting optical axis txa is equal to the angle between the second rotating shaft 121 and the receiving optical axis rxa. The second rotating shaft 121 is located on the angle bisector of the angle between the transmitting optical axis txa and the receiving optical axis rxa.

[0083] Figure 3 A top view schematic diagram of another lidar structure provided in some embodiments of this disclosure is shown.

[0084] like Figure 3 As shown, the second rotating shaft 221 is close to the transmitting optical axis txa and far from the receiving optical axis rxa. In some embodiments, the angle between the transmitting optical axis txa and the receiving optical axis rxa is 0°, and the distance between the second rotating shaft 221 and the transmitting optical axis txa is less than the distance between the second rotating shaft 221 and the receiving optical axis rxa. In some embodiments, there may be an angle between the transmitting optical axis txa and the receiving optical axis rxa, and the angle between the second rotating shaft 221 and the transmitting optical axis txa is less than the angle between the second rotating shaft 221 and the receiving optical axis rxa.

[0085] like Figure 2 and Figure 3 As shown, the spot size of the probe beam on reflectors 120 / 220 is no larger than the spot size of the echo on reflector 120. A smaller area on reflector 120 is used to reflect the probe beam, while a larger area is used to reflect the echo. This effectively improves the utilization rate of reflector 120, ensures full utilization of the receiving aperture, and contributes to guaranteeing detection performance.

[0086] In some embodiments, the optical-mechanical structure 101 can form a first field of view by moving about a first rotation axis 111; the mirror 120 can form a second field of view by moving about a second rotation axis 121. The first field of view is, for example, a horizontal field of view, and the second field of view is, for example, a vertical field of view. The maximum field of view of the first field of view can be 360°. The maximum field of view of the second field of view can be greater than 180°, for example, 200°, 220°, etc. Depending on the angle of rotation of the optical-mechanical structure about the first rotation axis, the first field of view can vary within the maximum field of view of the first field of view. Depending on the angle of rotation of the mirror about the second rotation axis, the second field of view can vary within the maximum field of view of the second field of view.

[0087] Figure 4A top-view structural schematic diagram of another lidar provided in some embodiments of this disclosure is shown. For example... Figure 1 As shown, in conjunction with reference Figure 4 The mounting bracket 430 at the corresponding position of the reflector 421 (e.g., the platform) Figure 4 The width d of the reflector (as shown by the midpoint line) is smaller than the width of the platform of the mounting bracket 430 at other locations. This ensures that when the reflective surface of the reflector reflects the probe beam downwards, the probe beam will not be blocked by the mounting bracket, thus creating a larger second field of view.

[0088] Figure 5 A schematic diagram of another lidar provided in some embodiments of this disclosure is shown.

[0089] The similarities to the foregoing embodiments will not be repeated here. The difference from the foregoing embodiments is that, in the lidar, the reflector 320 and the transceiver assembly 310 are relatively fixed.

[0090] like Figure 5 As shown, the lidar includes: a mounting bracket 332, which moves around a first rotating axis 311 and a second rotating axis 321; a transceiver assembly 310 fixedly connected to the mounting bracket 332; and a reflector 320 fixedly connected to the mounting bracket 332. The lidar includes an optomechanical structure 301. The optomechanical structure 301 includes the transceiver assembly 310 and the reflector 320. The optomechanical structure 301 of the lidar is at least partially fixed to the mounting bracket 332; for example, the optomechanical structure 301 is entirely fixed to the mounting bracket 332.

[0091] As the mounting bracket 332 moves about the first axis 311, the reflector 320 and transceiver assembly 310, which are fixedly connected to the mounting bracket 332, also move about the first axis 311. The optomechanical structure 301 moves at least partially with the mounting bracket 332 about the first axis 311; alternatively, the entire optomechanical structure 301 moves with the mounting bracket 332 about the first axis 311. As the mounting bracket 332 moves about the second axis 321, the reflector 320 and transceiver assembly 310, which are fixedly connected to the mounting bracket 332, also move about the second axis 321. The optomechanical structure 301 moves at least partially with the mounting bracket 332 about the second axis 321; alternatively, the entire optomechanical structure 301 moves with the mounting bracket 332 about the second axis 321.

[0092] The reflector 320 and the transceiver assembly 310 both move with the mounting bracket 332, around the first axis 311 and the second axis 321. The optomechanical structure 301 moves at least partially with the mounting bracket 332 around the first axis 311 and the second axis 321. For example, the entire optomechanical structure 301 moves with the mounting bracket 332 around the first axis 311 and the second axis 321, which can further reduce the obstruction of the mounting bracket 330 on the transmission and reception of optical signals, expand the field of view, and realize the field of view detection of the entire world by the lidar.

[0093] like Figure 5 In the embodiment shown, the lidar has a platform 331. The platform 331 can move around a first pivot 311, and a mounting bracket 332 is fixed on the platform 331. The mounting bracket 332 moves around the first pivot 311 as the platform 331 moves.

[0094] The reflector 320 and the transceiver assembly 310 are fixedly connected to the mounting bracket 332. As the mounting bracket 332 moves around the second rotating axis 321, the reflector 320 and the transceiver assembly 310 move around the second rotating axis 321 as a whole.

[0095] The mounting bracket 332 is movably connected to the platform 331. As the platform 331 moves around the first pivot 311, the mounting bracket 332 also moves around the first pivot 311. Since the reflector 320 and the transceiver assembly 310 are fixedly connected to the mounting bracket 332, the reflector 320 and the transceiver assembly 310 as a whole also move around the first pivot 311.

[0096] As with the foregoing embodiments, this disclosure will not repeat the details herein. In some embodiments, the optomechanical structure 101 can move about a first rotation axis 111 at a first frequency, and the reflector 120 can move about a second rotation axis 121 at a second frequency. The first frequency is greater than the second frequency.

[0097] In some embodiments, the ratio of the first frequency to the second frequency may not be an integer. The scanning trajectories of adjacent frames of the lidar do not overlap, enabling the lidar to operate in a non-repetitive scanning mode. By scanning multiple frames, the point cloud density can be increased without increasing the number of channels.

[0098] In some embodiments, the ratio of the first frequency to the second frequency can be an integer. The scanning trajectories of adjacent frames of the lidar overlap, allowing the lidar to operate in a repetitive scanning mode.

[0099] In some embodiments, the ratio of the first frequency to the second frequency is an integer greater than 10. The difference between the first frequency and the second frequency is large enough that a point cloud of sufficient density can be obtained with a single frame scan.

[0100] Figure 6A schematic diagram of a scanning path for a lidar provided in some embodiments of the present invention is shown. Figure 7 This diagram illustrates another scanning path of the lidar provided in some embodiments of the present disclosure. When the ratio of the first frequency to the second frequency is 10, the partial scanning path obtained by the lidar is shown below. Figure 6 As shown. When the ratio of the first frequency to the second frequency is 100, the partial scanning path obtained by the lidar is shown in the diagram. Figure 7 As shown, increasing the ratio of the first frequency to the second frequency can increase the point cloud density.

[0101] In some embodiments, the ratio of the first frequency to the second frequency can be a fixed value or an adjustable value. For example, the ratio of the first frequency to the second frequency can be changed by altering at least one of the first frequency or the second frequency. This allows the LiDAR to adjust its scanning mode and point cloud density according to the application scenario.

[0102] In some embodiments, the number of lasers and detectors can be one, forming a single channel. Through the optomechanical structure and the movement of mirrors, a single-channel lidar can also achieve three-dimensional field-of-view scanning. Large field-of-view detection can be achieved at a relatively low cost.

[0103] In some embodiments, the number of lasers and detectors can be multiple, forming multiple channels. The number of lasers and detectors can be the same or different. Increasing the number of lasers and detectors can increase the point cloud density. Figure 7 In the embodiment shown, the scanning path obtained by single-channel scanning is when the scanning frequencies of the first frequency and the second frequency differ by a factor of 100. Figure 8 In the embodiment shown, the scanning frequencies of the first frequency and the second frequency are also 100 times different, and the scanning path is obtained by the dual-channel scanning arranged in the horizontal direction. Figure 9 In the illustrated embodiment, the scanning frequencies of the first and second frequencies differ by a factor of 100, and the scanning path is obtained by scanning seven channels arranged horizontally. As the number of channels arranged horizontally increases, the density of the point cloud obtained by scanning increases significantly.

[0104] It should be noted that arranging at least two channels horizontally to increase point cloud density is only one example. In other embodiments of this disclosure, at least two channels can also be arranged vertically to achieve the effect of densifying the point cloud.

[0105] It should also be noted that in embodiments with multiple channels, multiple channels can be activated simultaneously to handle complex working scenarios, or only a portion of the channels can be activated initially to suit simpler working scenarios. In embodiments with multiple channels, the number of channels activated can be selected based on a comprehensive consideration of factors such as requirements, energy consumption, and the complexity of point cloud processing. This can improve the application range and flexibility of LiDAR.

[0106] While the above disclosure is provided, it is not limited thereto. Any person skilled in the art may make various alterations and modifications without departing from the spirit and scope of this disclosure; therefore, the scope of protection of this disclosure shall be determined by the scope defined in the claims.

Claims

1. A lidar, characterized in that, include: An optomechanical structure, wherein the optomechanical structure moves about a first rotation axis; The optomechanical structure includes: a transceiver assembly and a reflector; The transceiver assembly includes: a laser, a transmitting optics, a receiving optics, and a detector, wherein the transmitting optical axis and the receiving optical axis are not collinear; The mirror moves around a second axis of rotation, and the angle between the second axis of rotation and the first axis of rotation is greater than 0°. The second rotating shaft, the transmitting optical axis, and the receiving optical axis are parallel to each other, and the second rotating shaft is located between the transmitting optical axis and the receiving optical axis; The laser emits a detection beam, which is reflected by the object to form an echo. The size of the spot on the reflector of the detection beam is not greater than the size of the spot on the reflector of the echo.

2. The lidar as described in claim 1, characterized in that, The detection beam emitted by the laser passes sequentially through the emitting optics and the reflector before exiting into the environment; the echo passes sequentially through the reflector and the receiving optics before entering the detector.

3. The lidar as described in claim 1, characterized in that, The second rotating shaft is perpendicular to the first rotating shaft.

4. The lidar as described in claim 1, characterized in that, The angle between the second rotating shaft and the reflecting surface of the mirror is 45°.

5. The lidar as described in claim 1, characterized in that, The second rotating axis, the transmitting optical axis, and the receiving optical axis are coplanar.

6. The lidar as described in claim 1, characterized in that, The second rotating shaft is close to the transmitting optical axis and the second rotating shaft is far away from the receiving optical axis.

7. The lidar as described in claim 1, characterized in that, The first rotating axis is perpendicular to the plane containing the transmitting optical axis and the receiving optical axis.

8. The lidar as described in claim 1, characterized in that, The transceiver assembly further includes a transceiver circuit board, which is disposed on the transmitting optics and the receiving optics at the end away from the reflector.

9. The lidar as described in claim 8, characterized in that, The focal plane of the transmitting optics and the focal plane of the receiving optics are coplanar; the laser and the detector are mounted on the same transceiver circuit board.

10. The lidar as described in any one of claims 1 to 9, characterized in that, Also includes: The mounting bracket moves around the first rotating axis; the transceiver assembly is fixedly connected to the mounting bracket; the reflector is connected to the mounting bracket and can move relative to the mounting bracket.

11. The lidar as described in any one of claims 1 to 9, characterized in that, Also includes: The mounting bracket moves around the first rotating axis and the second rotating axis; the transceiver assembly is fixedly connected to the mounting bracket; and the reflector is fixedly connected to the mounting bracket.

12. The lidar as described in claim 1, characterized in that, The optomechanical structure moves about the first axis at a first frequency, and the mirror moves about the second axis at a second frequency; wherein the first frequency is greater than the second frequency.

13. The lidar as described in claim 1, characterized in that, The transceiver assembly includes multiple lasers.

14. The lidar as described in claim 1, characterized in that, The optomechanical structure moves around the first axis to form a first field of view; the mirror rotates around the second axis to form a second field of view, wherein the maximum field of view of the first field of view is 360° and the maximum field of view of the second field of view is greater than 180°.

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