Lidar

Abstract

A laser radar suitable for scanning detection in a first direction and a second direction, the first direction and the second direction having an included angle, comprising: a transmitting assembly for transmitting a detection beam; a first optical assembly arranged on an optical path of the detection beam; a scanning assembly for reflecting the detection beam passing through the first optical assembly to a target space, and for reflecting a return beam formed by the detection beam after being reflected by an obstacle; and a receiving assembly for receiving the return beam reflected by the scanning assembly; wherein the first optical assembly comprises a first beam expanding assembly, the first beam expanding assembly being a one-dimensional beam expanding assembly for expanding the detection beam in the first direction. The present application is advantageous in improving the detection performance of the laser radar.

Description

Technical Field

[0001] This invention relates to the field of lidar, and more particularly to a lidar system. Background Technology

[0002] LiDAR (Light Detection and Ranging) plays a crucial role in autonomous driving, performing tasks such as curb detection, obstacle recognition, and real-time localization and mapping (SLAM). Specifically, a LiDAR system comprises a laser emitting system and a light receiving system. The laser emitting system includes a light emitting unit that generates a detection beam. This beam is incident on an obstacle and reflected; a portion of the reflected light returns to the LiDAR and is received by the light receiving system, known as the echo beam. The receiving system measures the distance to the obstacle by measuring the time difference between transmitting the detection beam and receiving the echo beam, or the phase difference between the echo beam and the detection beam.

[0003] LiDAR can accurately measure the position (distance and angle), motion state (velocity, vibration, and attitude), and shape of targets, enabling it to detect, identify, distinguish, and track targets. Due to its advantages such as high measurement speed, high accuracy, and long range, LiDAR is widely used in autonomous vehicles.

[0004] The detection performance of existing lidar technology still needs to be improved. Summary of the Invention

[0005] The problem solved by the embodiments of the present invention is to provide a lidar that improves the detection performance of lidar.

[0006] To address the aforementioned problems, this invention provides a lidar suitable for scanning and detecting in a first direction and a second direction, wherein the first direction and the second direction are at an angle. The lidar includes: a transmitting component for transmitting a detection beam; a first optical component disposed in the optical path of the detection beam; a scanning component for reflecting the detection beam passing through the first optical component to a target space, and also for reflecting the echo beam formed by the detection beam after being reflected by an obstacle; and a receiving component for receiving the echo beam reflected by the scanning component. The first optical component includes a first beam expander, which is a one-dimensional beam expander used to expand the detection beam only in the first direction.

[0007] Compared with the prior art, the technical solution of the embodiments of the present invention has the following advantages:

[0008] In the lidar provided in this embodiment of the invention, the lidar is adapted to perform scanning detection in a first direction and a second direction. The first optical component includes a first beam expander, which is a one-dimensional beam expander used to expand the detection beam in the first direction. In this embodiment of the invention, the detection beam is expanded by the one-dimensional beam expander, which increases the aperture of the detection beam, thus improving the coverage of the detection beam and increasing the aperture of the received echo beam, thereby increasing the energy of the received echo beam and thus improving the range of the lidar. Moreover, in this embodiment of the invention, the lidar performs scanning detection in both the first and second directions, and the one-dimensional beam expander only expands the detection beam in the first direction. Therefore, the detection beam is not expanded in the second direction, and the focal length of the lidar in the second direction is not further increased. Consequently, when receiving the echo beam, the spot drift of the echo beam is not increased in the second direction, which helps to improve the receiving efficiency of the receiving component and thus improves the detection performance of the lidar. Attached Figure Description

[0009] Figure 1 This is a structural diagram and optical path diagram of a lidar;

[0010] Figures 2 to 3 This is a structural schematic diagram and optical path diagram of the first embodiment of the lidar of the present invention;

[0011] Figures 4 to 5 This is a structural schematic diagram and optical path diagram of the second embodiment of the lidar of the present invention;

[0012] Figures 6 to 7 This is a structural schematic diagram and optical path diagram of the third embodiment of the lidar of the present invention;

[0013] Figures 8 to 9 This is a structural schematic diagram and optical path diagram of the fourth embodiment of the lidar of the present invention. Detailed Implementation

[0014] As the background technology shows, the detection performance of lidar needs improvement. This paper analyzes the reasons why the current detection performance of a particular lidar needs further improvement.

[0015] Figure 1 This is a schematic diagram of the structure and optical path of a lidar.

[0016] refer to Figure 1 The lidar is adapted to be in a first direction (e.g., Figure 1 The Z direction in the XYZ three-dimensional coordinate system is shown) and the second direction (as shown) Figure 1The lidar performs scanning detection in the Y direction (as shown in the figure). It includes: a transmitting component 10 for emitting a detection beam; a concave lens 30 disposed in the optical path of the detection beam for expanding the beam in a first and second direction; a scanning component for reflecting the detection beam through the concave lens 30 to the target space, and also for reflecting the echo beam formed after the detection beam is reflected by an obstacle. The scanning component includes a first scanning element 41 for scanning the detection beam in the first direction, and a second scanning element 42 for scanning the beam in the second direction, wherein the scanning speed of the first scanning element 41 is less than the scanning speed of the second scanning element 42; and a receiving component 20 for receiving the echo beam reflected by the scanning component. The lidar also includes a main optical component (such as a collimating lens or collimating lens group, not shown in the figure) for collimating the detection beam and focusing the echo beam. The transmitting component 10 and the receiving component 20 share the concave lens 30 and the main optical component. Figure 1 The illustrated lidar is a lidar with a coaxial optical path.

[0017] For coaxial optical path lidar, the transmitting component 10 and the receiving component 20 are typically connected to the same transceiver port using waveguides. After the transceiver port emits a probe beam, when the echo beam returns to the lidar, the scanning component has already rotated a certain angle, causing the focusing position of the echo beam to deviate from the transceiver port, resulting in beam drift (e.g., ...). Figure 1 (As shown by the dashed line). The faster the scanning speed of the scanning element and the farther the distance of the obstacle, the greater the drift of the light spot.

[0018] When the probe beam is expanded in both the first and second directions, its equivalent focal length in both directions increases compared to the main optical components. Simultaneously, the scanning components scan in both directions, which can easily increase the beam drift of the echo beam when receiving it. In particular, the second scanning element 42 has a higher scanning speed, and expanding the beam in its scanning direction (i.e., the second direction) further exacerbates the problem of increased beam drift. Moreover, in lidar, the transceiver ports are typically small, and beam drift can reduce the efficiency of receiving the echo beam (e.g., ...). Figure 1 (As shown by the dashed line optical path), which seriously affects the detection capability of lidar.

[0019] To address the aforementioned technical problem, embodiments of the present invention provide a lidar suitable for scanning and detecting in a first direction and a second direction, wherein the first direction and the second direction are at an angle. The lidar includes: a transmitting component for transmitting a detection beam; a first optical component disposed in the optical path of the detection beam; a scanning component for reflecting the detection beam passing through the first optical component to a target space, and also for reflecting the echo beam formed by the detection beam after reflection by an obstacle; and a receiving component for receiving the echo beam reflected by the scanning component. The first optical component includes a first beam expander, which is a one-dimensional beam expander used to expand the detection beam only in the first direction.

[0020] In the lidar provided in this embodiment of the invention, the detection beam is expanded by a one-dimensional beam expander, which increases the aperture of the detection beam, thus improving the coverage of the detection beam and increasing the aperture of the received echo beam, thereby increasing the energy of the received echo beam and thus improving the range of the lidar. Moreover, in this embodiment of the invention, the lidar performs scanning detection in the first and second directions, while the one-dimensional beam expander only expands the detection beam in the first direction. Therefore, the detection beam is not expanded in the second direction, and the focal length of the lidar in the second direction is not further increased. Consequently, when receiving the echo beam, the spot drift of the echo beam in the second direction is not increased, which helps to improve the receiving efficiency of the receiving component and thus improves the detection performance of the lidar.

[0021] To make the above-mentioned objects, features and advantages of the embodiments of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0022] refer to Figures 2 to 3 This is a structural schematic diagram and optical path diagram of the first embodiment of the lidar of the present invention. Figure 2 This is a view of the lidar along the Z-direction. Figure 3 This is a view of the lidar along the Y direction.

[0023] LiDAR is suitable for use in the first direction (e.g.) Figure 2 The Z direction in the XYZ three-dimensional coordinate system is shown) and the second direction (as shown) Figure 2The laser radar performs scanning detection in the Y direction (as shown in the image), with an angle between the first direction and the second direction. The laser radar includes: a transmitting component 100 for emitting a detection beam; a first optical component 300 disposed on the optical path of the detection beam; a scanning component 400 for reflecting the detection beam passing through the first optical component 300 to the target space, and also for reflecting the echo beam formed after the detection beam is reflected by an obstacle; and a receiving component 200 for receiving the echo beam reflected by the scanning component 400. The first optical component 300 includes a first beam expander 320, which is a one-dimensional beam expander used to expand the detection beam in the first direction.

[0024] The emitting component 100 is used to emit a probe beam.

[0025] In this embodiment, the emitting component 100 includes a laser. The laser can be any type of semiconductor laser, solid-state laser, or fiber laser.

[0026] The receiving component 200 is used to detect the echo beam in order to enable the lidar to detect obstacles.

[0027] In this embodiment, the receiving component 200 includes a photodetector adapted to convert optical signals into electrical signals. For example, the photodetector is a photodiode (PD), an avalanche photodiode (APD), a silicon photomultiplier tube (SiPM), or a single-photon avalanche diode (SPAD) array.

[0028] In this embodiment, the receiving component 200 is used to receive the echo beam reflected by the scanned component 400 and passed through the first optical component 300. Correspondingly, the lidar is a coaxial lidar.

[0029] In a specific embodiment of the present invention, the lidar includes at least one transceiver port 110, which is coupled to the transmitting component 100 and the receiving component 200, respectively, and is adapted to transmit a detection beam and receive an echo beam.

[0030] In a specific embodiment of the present invention, the transceiver port 110 is coupled to the transmitting component 100 and the receiving component 200 respectively. The transmitting component 100 and the receiving component 200 can transmit light between the transceiver port 110 through the waveguide, so that the transmitting component 100 and the receiving component 200 do not need to be set on the focal plane of the first optical component 300. This is beneficial to improve the flexibility of the lidar component setup and reduce the size of the lidar.

[0031] The first beam expander 320 is a one-dimensional beam expander used to expand the probe beam in a first direction and to focus the echo beam in a first direction.

[0032] In this embodiment, the probe beam is expanded by a one-dimensional beam expander, which increases the probe beam aperture, thus improving the coverage of the probe beam and increasing the aperture of the received echo beam, thereby increasing the energy of the received echo beam and improving the range of the lidar. Furthermore, in this embodiment, the lidar performs scanning detection in the first and second directions, and the one-dimensional beam expander only expands the probe beam in the first direction, without expanding it in the second direction. Therefore, the focal length of the lidar in the second direction is not further increased, and the spot drift of the echo beam is not increased in the second direction when receiving the echo beam. This improves the receiving efficiency of the receiving component 200 and correspondingly enhances the detection performance of the lidar.

[0033] In some embodiments of the present invention, the one-dimensional beam expander includes a cylindrical concave lens having curvature in a first direction, thereby enabling beam expansion of the probe beam in the first direction and not expanding the probe beam in a second direction.

[0034] In other embodiments of the present invention, the one-dimensional beam expander is a lens group, which includes a cylindrical concave lens and a cylindrical convex lens arranged coaxially, both of which have curvature in a first direction.

[0035] A one-dimensional beam expander is constructed using a lens group, which includes a coaxially arranged cylindrical concave lens and a cylindrical convex lens. The combination of concave and convex lenses can reduce or eliminate aberrations.

[0036] In some embodiments of the present invention, there are multiple cylindrical convex lenses, which are respectively disposed on both sides of the optical axis of the cylindrical concave lens, thereby helping to further reduce or eliminate aberrations. At the same time, the cylindrical convex lens disposed downstream of the optical path of the cylindrical concave lens can also collimate the probe beam.

[0037] Reference Figure 2 and Figure 3 The first beam expander 320 is a lens group, including a cylindrical concave lens and two cylindrical convex lenses arranged coaxially. Both the cylindrical convex lens and the cylindrical concave lens have curvature in the first direction. The two cylindrical convex lenses are respectively arranged on both sides of the optical axis of the cylindrical concave lens, thereby using a relatively simple combination to reduce or eliminate aberrations.

[0038] Continue to refer to Figure 2 and Figure 3 As shown, the first optical component 300 further includes a collimating element 310, which is used to collimate the probe beam. The collimating element 310 is located upstream or downstream of the optical path of the first beam expander 320.

[0039] The collimating element 310 is used to collimate the probe beam and to focus the echo beam.

[0040] In this embodiment, the collimating element 310 includes a convex lens to achieve the collimation effect of the light beam. In other embodiments of the present invention, the collimating element 310 may further include a lens group to achieve collimation of the detection light beam.

[0041] The scanning component 400 is used to reflect the detection beam that has passed through the first optical component 300 to the target space, and is also used to reflect the echo beam formed after the detection beam is reflected by the obstacle.

[0042] In this embodiment, the scanning speed of the lidar in the first direction is less than the scanning speed in the second direction, thereby enabling grating scanning of the lidar's two-dimensional field of view. That is, after scanning one row along the second direction, the lidar scans to the next row along the first direction, and then scans one row along the second direction in the next row, and so on, to achieve two-dimensional scanning and completely cover the lidar's field of view.

[0043] It should be noted that the scanning speed can be represented by the time interval between two consecutive detection beams.

[0044] It should also be noted that in this embodiment, the detection beam is not expanded in the second direction, so that the focal length of the lidar in the second direction remains the same as that of the collimating element 310. Therefore, although the scanning speed of the lidar in the second direction is relatively large, it will not increase the spot drift of the echo beam, which helps to ensure the receiving efficiency of the receiving component 200 and correspondingly ensures the detection performance of the lidar. The scanning speed of the lidar in the first direction is relatively slow. Even if the first beam expander 320 increases the focal length of the lidar in the first direction, the increase in spot drift is still small. At the same time, the first beam expander 320 expands the detection beam in the first direction, which correspondingly increases the focal length of the lidar in the first direction, making the aperture of the detection beam in the first direction larger and the coverage area of ​​the detection beam larger. Consequently, the aperture of the echo beam that the receiving component 200 can receive in the first direction is larger, which increases the light energy of the received echo beam and is beneficial to improving the range measurement capability of the lidar.

[0045] Continue to refer to Figure 2 and Figure 3 The scanning assembly 400 includes two one-dimensional scanning elements 410 and 420, which are adapted to deflect about axes perpendicular to the first direction and the second direction, respectively, thereby deflecting the probe beam to different angles in the first direction and the second direction.

[0046] The scanning assembly 400 is composed of two one-dimensional scanning elements 410 and 420, which allows for flexible adjustment of the configuration of the two one-dimensional scanning elements 410 and 420 to obtain a detection optical path that is adapted to the detection requirements. The one-dimensional scanning element 420, which deflects about an axis perpendicular to the second direction, is used to perform scanning in the second direction, and the one-dimensional scanning element 410, which deflects about an axis perpendicular to the first direction, is used to perform scanning in the first direction.

[0047] Correspondingly, the scanning speed of the one-dimensional scanning element 420, which deflects about an axis perpendicular to the second direction, is greater than the scanning speed of the one-dimensional scanning element 410, which deflects about an axis perpendicular to the first direction.

[0048] It should be noted that the scanning speed of a one-dimensional scanning element can be determined by the rotational speed of the scanning element around its axis.

[0049] In a specific embodiment of the present invention, the one-dimensional scanning elements 410 and 420 include a galvanometer, a rotating mirror or a tilting mirror, which scans and reflects the detection beam to form an outgoing beam for detecting the obstacle. The outgoing beam is reflected by the obstacle to form an echo beam, which is then reflected by the galvanometer, rotating mirror or tilting mirror and enters the receiving component 200.

[0050] In other embodiments, the scanning assembly may further include a two-dimensional scanning element adapted to deflect about an axis perpendicular to the first and second directions.

[0051] By using two-dimensional scanning elements, the scanning elements that perform scanning in the first and second directions can be integrated, which helps to simplify the structure of the lidar and reduce its size.

[0052] Specifically, the two-dimensional scanning element includes a two-dimensional galvanometer.

[0053] Figures 4 to 5 This is a structural schematic diagram and optical path diagram of the second embodiment of the lidar of the present invention. The lidar is adapted to be used in a first direction (e.g., Figure 4 The Z direction in the XYZ three-dimensional coordinate system is shown) and the second direction (as shown) Figure 4 Scanning and detection are performed in the Y direction (as shown in the image).

[0054] The similarities between this embodiment and the previous embodiments will not be repeated here. The difference between this embodiment and the previous embodiments is that the lidar includes multiple transceiver ports arranged along the first direction, and the scanning component is a one-dimensional scanning element.

[0055] Reference Figures 4 to 5 , Figure 4 This is a view of the lidar along the Z-direction. Figure 5This is a view of the lidar along the Y direction. The lidar includes multiple transceiver ports 111 arranged along the first direction. The transceiver ports 111 are coupled to the transmitting component 101 and the receiving component 201, respectively. The multiple transceiver ports 111 are all adapted to transmit a probe beam and receive an echo beam.

[0056] Multiple transceiver ports 111 are arranged along the first direction. The multiple transceiver ports 111 are used to emit detection beams at intervals, thereby enabling the scanning of the field of view of the lidar in the first direction by emitting detection beams at intervals. In the structure of the lidar, by arranging multiple transceiver ports 111 along the first direction, the scanning element that scans in the first direction can be replaced, simplifying the optical path of the lidar and improving the system integration.

[0057] In this embodiment, the scanning component 401 is a one-dimensional scanning element 411. The one-dimensional scanning element 411 is adapted to deflect around an axis perpendicular to the second direction, thereby deflecting the probe beam in the second direction to different angles to achieve scanning of the second direction.

[0058] In this embodiment, multiple transceiver ports 111 are arranged along the first direction to realize the scanning of obstacles in the first direction. Thus, the scanning component 401 can be only a one-dimensional scanning element 411 to realize the scanning of obstacles in the second direction. By combining the multiple transceiver ports 111 arranged along the first direction and the one-dimensional scanning element 411, the scanning of obstacles in the first and second directions can be completed, which helps to simplify the structure of the lidar and improve the integration.

[0059] In this embodiment, the first beam expander 321 is a one-dimensional beam expander, used to expand the probe beam in a first direction and to focus the echo beam in a first direction.

[0060] In this embodiment, the probe beam is expanded by a one-dimensional beam expander, which increases the probe beam aperture, thus improving the coverage of the probe beam and increasing the aperture of the received echo beam, thereby increasing the energy of the received echo beam and improving the range of the lidar. Furthermore, in this embodiment, the lidar performs scanning detection in the first and second directions, and the one-dimensional beam expander only expands the probe beam in the first direction, without expanding it in the second direction. Therefore, the focal length of the lidar in the second direction is not further increased, and the spot drift of the echo beam is not increased in the second direction when receiving the echo beam. This improves the receiving efficiency of the receiving component 200 and correspondingly enhances the detection performance of the lidar.

[0061] In this embodiment, the first beam expander 321 is a lens group, including a cylindrical concave lens and two cylindrical convex lenses arranged coaxially. Both the cylindrical convex lens and the cylindrical concave lens have curvature in the first direction. The two cylindrical convex lenses are respectively arranged on both sides of the optical axis of the cylindrical concave lens, thereby using a relatively simple combination to reduce or eliminate aberrations.

[0062] A one-dimensional beam expander is constructed using a lens group, which includes a coaxially arranged cylindrical concave lens and a cylindrical convex lens. The combination of concave and convex lenses can reduce or eliminate aberrations.

[0063] In other embodiments of the present invention, the one-dimensional beam expander includes a cylindrical concave lens having curvature in a first direction, thereby enabling beam expansion of the probe beam in the first direction and not expanding the probe beam in a second direction.

[0064] In some embodiments of the present invention, there are multiple cylindrical convex lenses, which are respectively disposed on both sides of the optical axis of the cylindrical concave lens, thereby helping to further reduce or eliminate aberrations. At the same time, the cylindrical convex lens disposed downstream of the optical path of the cylindrical concave lens can also collimate the probe beam.

[0065] Figures 6 to 7 This is a structural schematic diagram and optical path diagram of the third embodiment of the lidar of the present invention. The lidar is adapted to be used in a first direction (e.g., Figure 6 The Z direction in the XYZ three-dimensional coordinate system is shown) and the second direction (as shown) Figure 6 Scanning and detection are performed in the Y direction (as shown in the image).

[0066] The similarities between this embodiment and the previous embodiments will not be repeated here. The difference between this embodiment and the previous embodiments is that the lidar further includes a second optical component, which is disposed in the optical path of the echo beam and is suitable for focusing the echo beam.

[0067] Reference Figures 6 to 7 , Figure 6 This is a view of the lidar along the Z-direction. Figure 7 This is a view of the lidar along the Y direction. The lidar includes a scanning assembly comprising a one-dimensional scanning element 412 and a one-dimensional scanning element 422, respectively adapted to deflect around axes perpendicular to the first and second directions, thereby deflecting the detection beam to different angles in the first and second directions, respectively.

[0068] It should be noted that in this embodiment, the probe beam is reflected by different surfaces of the one-dimensional scanning element 422, thereby achieving optical path separation between the probe beam and the echo beam and forming a side-axis optical path lidar.

[0069] The scanning assembly is composed of two one-dimensional scanning elements 412 and 422, which allows for flexible adjustment of the configuration of the two one-dimensional scanning elements 412 and 422 to obtain a detection optical path that is adapted to the detection requirements. The one-dimensional scanning element 422, which deflects about an axis perpendicular to the second direction, is used to perform scanning in the second direction, and the one-dimensional scanning element 412, which deflects about an axis perpendicular to the first direction, is used to perform scanning in the first direction.

[0070] Correspondingly, the scanning speed of the one-dimensional scanning element 422, which deflects about an axis perpendicular to the second direction, is greater than the scanning speed of the one-dimensional scanning element 412, which deflects about an axis perpendicular to the first direction.

[0071] It should be noted that the scanning speed of a one-dimensional scanning element can be determined by the rotational speed of the scanning element around its axis.

[0072] In a specific embodiment of the present invention, the one-dimensional scanning element 412 includes a galvanometer, a rotating mirror, or a tilting mirror, which scans and reflects the detection beam to form an outgoing light for detecting the obstacle. The outgoing light is reflected by the obstacle to form an echo beam, which is then reflected by the galvanometer, rotating mirror, or tilting mirror and enters the receiving component.

[0073] The lidar also includes a second optical component 302, which is disposed in the optical path of the echo beam and is adapted to focus the echo beam.

[0074] The second optical component 302 is disposed on the optical path of the echo beam and is suitable for focusing the echo beam. Correspondingly, the lidar is a side-axis lidar. The transmitting component 102 and the receiving component 202 are disposed independently. The optical paths of the detection beam and the echo beam are independent of each other, which helps to reduce the mutual interference between the echo beam and the transmitting beam and improve the signal-to-noise ratio of the lidar.

[0075] In this embodiment, the second optical component 302 includes a second beam expander 322, which is a one-dimensional beam expander used to focus the echo beam in a first direction.

[0076] Correspondingly, since the optical paths of the probe beam and the echo beam are independent of each other, it is beneficial to suppress the mutual interference between the echo beam and the emitted beam and improve the signal-to-noise ratio of the lidar.

[0077] In this embodiment, the second optical component 302 further includes a collimating element 312, which is used to focus the echo beam. The collimating element 312 is located upstream or downstream of the optical path of the second beam expander 322.

[0078] In this embodiment, the collimating element 312 includes a convex lens to achieve a focusing effect on the light beam.

[0079] Figures 8 to 9This is a structural schematic diagram and optical path diagram of the fourth embodiment of the lidar of the present invention. The lidar is adapted to be used in a first direction (e.g., Figure 8 The Z direction in the XYZ three-dimensional coordinate system is shown) and the second direction (as shown) Figure 8 Scanning and detection are performed in the Y direction (as shown in the image).

[0080] The similarities between this embodiment and the previous embodiments will not be repeated here. The difference between this embodiment and the previous embodiments is that the transmitting component includes a plurality of transmitting ports arranged along the first direction, and the receiving component includes a plurality of receiving ports arranged along the first direction.

[0081] Reference Figures 8 to 9 , Figure 8 This is a view of the lidar along the Z-direction. Figure 9 This is a view of the lidar along the Y direction. The transmitting component 103 includes a plurality of transmitting ports 113 arranged along the first direction, each of which is adapted to transmit a detection beam. The receiving component 203 includes a plurality of receiving ports 114 arranged along the first direction, each of which is adapted to receive an echo beam. The transmitting ports 113 and the receiving ports 114 correspond one-to-one.

[0082] In this embodiment, the lidar is a side-axis lidar, with the transmitting component 103 and the receiving component 203 independently configured. The optical paths of the detection beam and the echo beam are different, which helps to reduce the restriction on the optical path of the echo beam and allows for flexible adjustment of the optical path according to detection requirements. Meanwhile, the transmitting component 103 includes multiple transmitting ports 113 arranged along the first direction for emitting detection beams at intervals, and the receiving component 203 includes multiple receiving ports 114 arranged along the first direction for emitting detection beams at intervals and receiving echo beams at intervals. Thus, by emitting detection beams at intervals, obstacles can be scanned in the first direction. In addition, by combining a one-dimensional scanning element in the lidar structure, obstacles can be scanned in both the first and second directions, while achieving flexible adjustment of the optical path, simplification of the optical path, and cost savings.

[0083] In this embodiment, the transmitting port 113 and the receiving port 114 correspond one-to-one, thereby achieving accurate detection of multiple optical channels.

[0084] Given a fixed number of lines in a lidar system, the field of view (FOV) and angular resolution of a lidar system are inversely related. That is, if the FOV is increased, the angular resolution decreases, and the lidar cannot distinguish distant objects; if the angular resolution is increased, the FOV decreases, and the lidar's detection range at close range is insufficient.

[0085] In some embodiments of the present invention, the one-dimensional beam expander is a zoom beam expander, which is configured to have multiple different equivalent focal lengths in a first direction. The multiple different equivalent focal lengths can be applied to multiple different detection scenarios, thereby improving the adaptability of the lidar to different detection scenarios and enabling the lidar to be widely used in various detection scenarios.

[0086] Specifically, in this embodiment, the one-dimensional beam expander is a lens group, which includes multiple lenses arranged coaxially and whose positions are adjustable. This allows for the acquisition of different focal distances between adjacent lenses by adjusting the positions of the multiple lenses, thereby obtaining multiple different equivalent focal lengths in the first direction.

[0087] Accordingly, in this embodiment, the lidar further includes a driving component (not shown) for adjusting the position of each lens in the lens group along the optical axis to obtain an equivalent focal length.

[0088] Specifically, different focal distances between adjacent lenses correspond to different equivalent focal lengths of the lens group. A driving component is set up in the lidar, and this driving component is connected to multiple lenses of the one-dimensional beam expander. During detection, the equivalent focal length of the lens group is determined according to the detection scene, distance measurement capability, or field of view requirements. The required focal distance between adjacent lenses can be obtained, and the driving component is used to adjust each lens to its corresponding position, thereby achieving different focal lengths and corresponding detection scene switching.

[0089] Specifically, in this embodiment, the lidar configures multiple different equivalent focal lengths of the zoom beam expander component according to the detection scenario. The detection scenario includes at least a first detection scenario and a second detection scenario. The detection distance of the second detection scenario is greater than that of the first detection scenario. Therefore, the equivalent focal length of the zoom beam expander component corresponding to the second detection scenario is greater than that of the zoom beam expander component corresponding to the first detection scenario.

[0090] In detection scenarios, when detecting nearby scenes, a smaller equivalent focal length can be used to achieve a larger field of view (FOV), which is beneficial for expanding the detection range of the lidar at close range. When detecting distant scenes, a larger equivalent focal length can be used to achieve a smaller angular resolution. At the same time, increasing the focal length of the one-dimensional beam expander in the first direction can improve the beam expansion ratio (the ratio of the size of the beam in the first direction after being expanded by the one-dimensional beam expander to the size of the beam in the first direction before beam expansion), thereby increasing the beam aperture and enhancing the lidar's range finding capability, which is beneficial for distinguishing distant objects.

[0091] Therefore, in this embodiment, the detection distance of the second detection scenario is greater than the detection distance of the first detection scenario, and the equivalent focal length of the corresponding zoom beam expander component is: the equivalent focal length of the second detection scenario is greater than the equivalent focal length of the first detection scenario.

[0092] As an example, the first detection scenario includes an urban road scenario, and the second detection scenario includes a highway scenario.

[0093] Using embodiments of the present invention, when focusing on measuring near scenes such as urban roads, the focal length of the one-dimensional beam expander can be reduced to achieve a larger field of view (FOV). At the same time, the disadvantage of reduced measurement range due to reduced aperture is not critical when measuring near scenes. When focusing on distant scenes such as highways, the focal length of the one-dimensional beam expander can be increased to achieve a smaller angular resolution. At the same time, the beam expansion ratio increases, the aperture increases, and the distance measurement capability is enhanced to adapt to distance measurement scenarios.

[0094] While the present invention has been disclosed above, it is not limited thereto. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of the invention; therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.

Claims

1. A lidar suitable for scanning and detecting in a first direction and a second direction, wherein the first direction and the second direction are at an angle, and the lidar's scanning speed in the first direction is less than its scanning speed in the second direction; characterized in that, The lidar includes: The transmitting component is used to emit a probe beam; A first optical component is disposed in the optical path of the detection beam; The scanning component is used to reflect the detection beam that has passed through the first optical component to the target space, and is also used to reflect the echo beam formed after the detection beam is reflected by the obstacle; A receiving component for receiving the echo beam reflected by the scanning component; The first optical component includes a first beam expander, which is a one-dimensional beam expander used to expand the probe beam in a first direction.

2. The lidar as described in claim 1, characterized in that, The one-dimensional beam expander includes a cylindrical concave lens, which has curvature in the first direction.

3. The lidar as described in claim 1, characterized in that, The one-dimensional beam expander includes a lens group, which includes a cylindrical concave lens and a cylindrical convex lens arranged coaxially, both of which have curvature in the first direction.

4. The lidar as described in claim 3, characterized in that, The cylindrical convex lens is a plurality of such lenses, which are respectively disposed on both sides of the optical axis of the cylindrical concave lens.

5. The lidar as described in claim 1, characterized in that, The scanning assembly includes two one-dimensional scanning elements, which are respectively adapted to deflect about axes perpendicular to the first direction and the second direction; or, The scanning assembly includes a two-dimensional scanning element adapted to deflect about an axis perpendicular to the first direction and the second direction.

6. The lidar as described in claim 5, characterized in that, The one-dimensional scanning element includes a galvanometer, a rotating mirror, or a tilting mirror; or, the two-dimensional scanning element includes a two-dimensional galvanometer.

7. The lidar as described in claim 1, characterized in that, The receiving component is used to receive the echo beam that has been reflected by the scanning component and passed through the first optical component; The lidar includes at least one transceiver port, which is coupled to the transmitting component and the receiving component respectively, and is adapted to transmit the detection beam and receive the echo beam.

8. The lidar as described in claim 7, characterized in that, The lidar includes multiple transceiver ports arranged along a first direction. The transceiver ports are respectively coupled to the transmitting component and the receiving component. The multiple transceiver ports are all adapted to emit a detection beam and receive the echo beam.

9. The lidar as described in claim 1, characterized in that, The lidar also includes a second optical component disposed in the optical path of the echo beam, adapted to focus the echo beam; The second optical component includes a second beam expander, which is a one-dimensional beam expander used to focus the echo beam in a first direction.

10. The lidar as described in claim 9, characterized in that, The transmitting component includes a plurality of transmitting ports arranged along the first direction, each of which is adapted to transmit a probe beam; the receiving component includes a plurality of receiving ports arranged along the first direction, each of which is adapted to receive an echo beam; the transmitting ports and the receiving ports correspond one-to-one.

11. The lidar as described in claim 8 or 10, characterized in that, The scanning component is a one-dimensional scanning element, which is adapted to deflect about an axis parallel to the first direction.

12. The lidar as described in claim 1, characterized in that, The first optical component further includes a collimating element for collimating the probe beam, wherein the collimating element is located upstream or downstream of the optical path of the first beam expander.

13. The lidar as described in claim 1 or 9, characterized in that, The one-dimensional beam expander is a zoom beam expander, configured to have multiple different equivalent focal lengths in the first direction.

14. The lidar as described in claim 13, characterized in that, The one-dimensional beam expander is a lens group, which includes multiple lenses that are coaxially arranged and whose positions are adjustable. The lidar further includes a driving component for adjusting the position of each lens in the lens group along the optical axis to obtain the equivalent focal length.

15. The lidar as described in claim 13, characterized in that, The lidar is configured with multiple different equivalent focal lengths of the zoom beam expander component according to the detection scenario. The detection scenario includes a first detection scenario and a second detection scenario. The detection distance of the second detection scenario is greater than the detection distance of the first detection scenario. The equivalent focal length of the zoom beam expander component corresponding to the second detection scenario is greater than the equivalent focal length of the zoom beam expander component corresponding to the first detection scenario.

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