Laser radar

Abstract

The invention provides a laser radar, and the laser radar comprises a light source module which is used for generating detection light; the transmitting lens is positioned on the light emitting side of the light source module, is used for receiving and emitting the detection light and is provided with a first optical axis; the photoelectric detection module is used for receiving echo light, and the echo light is formed by reflecting the detection light through a target object; the receiving lens is located on the light incident side of the photoelectric detection module and used for receiving the echo light and emitting the echo light to the photoelectric detection module, the receiving lens is provided with a second optical axis, and the first optical axis is parallel to the second optical axis; the focal length of the receiving lens is smaller than that of the transmitting lens. The focal length of the receiving lens is smaller than that of the transmitting lens, so that the size of the receiving lens is smaller than that of the transmitting lens. Compared with a scheme in which a transmitting lens and a receiving lens with the same aperture and focal length are adopted, the laser radar in the embodiment of the invention can reduce the size of the receiving lens, thereby reducing the overall size of the laser radar.

Description

Technical Field

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

[0002] LiDAR (Light Detection and Ranging) is a detection device that calculates the distance to an object by emitting a laser beam and detecting the echo signal reflected back from the object's surface. Based on whether the light source module and photoelectric detection module use the same set of optical lenses to emit and receive the laser beam, LiDAR can be divided into coaxial LiDAR and off-axis LiDAR. Compared to coaxial LiDAR, off-axis LiDAR has a simpler structure and higher echo reception capability, making it a focus of research and development for many manufacturers.

[0003] However, off-axis lidar also suffers from a large size. Therefore, how to reduce the overall size of lidar without affecting its detection function is a problem worth studying. Summary of the Invention

[0004] This application provides a lidar that aims to reduce the overall size of the lidar without affecting its detection function.

[0005] The specific technical solution is as follows:

[0006] An embodiment of the first aspect of this application provides a lidar, the lidar comprising:

[0007] The light source module is used to generate the probe light;

[0008] A transmitting lens, located on the light-emitting side of the light source module, is used to receive the probe light and emit it; the transmitting lens has a first optical axis.

[0009] A photoelectric detection module is used to receive echo light, which is formed by the reflection of the detection light from a target object; and

[0010] A receiving lens, located on the light-incident side of the photoelectric detection module, is used to receive the echo light and emit it to the photoelectric detection module. The receiving lens has a second optical axis, and the first optical axis is parallel to the second optical axis.

[0011] The focal length of the receiving lens is smaller than that of the transmitting lens.

[0012] In this embodiment of the lidar, the first optical axis of the transmitting lens is parallel to the second optical axis of the receiving lens, and the focal length f2 of the receiving lens is smaller than the focal length f1 of the transmitting lens. This makes the size of the receiving lens smaller than that of the transmitting lens, thus creating a small-sized receiving lens. Therefore, compared to related technologies that use identical transmitting and receiving lenses or large-sized receiving lenses, the lidar in this embodiment can reduce the external dimensions of the light-transmitting area, and consequently, the overall size of the lidar can also be reduced.

[0013] In some embodiments, the transmitting lens and the receiving lens satisfy the following relationship:

[0014] 0.5≤f2 / f1≤0.9;

[0015] Where f1 is the focal length of the transmitting lens and f2 is the focal length of the receiving lens.

[0016] In some embodiments, the light source module and the photoelectric detection module satisfy the following relationship:

[0017] H 2x <H 1x H 2y <H 1y ;

[0018] Among them, H 1x H represents the dimension of the light-emitting surface of the light source module along the first direction. 1y H represents the dimension of the light-emitting surface of the light source module along the second direction. 2x H represents the dimension of the photosensitive surface of the photodetector module along the first direction. 2y The first direction is the dimension of the photosensitive surface of the photoelectric detection module along the second direction, where the first direction is the direction determined by one of the first optical axis and the second optical axis pointing to the other, and the second direction is perpendicular to the first optical axis and the first direction, respectively.

[0019] In some embodiments, the light source module and the photoelectric detection module satisfy the following relationship:

[0020] 0.5≤H 2x / H 1x ≤0.9, 0.5≤H 2y / H 1y ≤0.9;

[0021] Furthermore, H 2x With H 1x The ratio is equal to H 2y With H 1y The ratio of .

[0022] In some embodiments, along the extension direction of the first optical axis, the photodetector module is located on the side of the light source module facing the emitting lens; and / or,

[0023] Along the extension direction of the first optical axis, the emitting lens has a first focal plane facing the light source module, and the receiving lens has a second focal plane facing the photoelectric detection module, the second focal plane being located on the side of the first focal plane facing the emitting lens.

[0024] In some embodiments, the transmitting lens includes at least one first lens, the projection of which along the first optical axis is circular;

[0025] The receiving lens includes at least one second lens, the projection of which along the second optical axis is circular.

[0026] In some embodiments, the transmitting lens includes at least one first lens, the side of the first lens includes a first arc surface and a first plane, the first plane is located on the side of the first lens closer to the receiving lens along a first direction, the radius of the first arc surface is a first radius R1, the distance between the first optical axis and the first plane is a first distance L1, and the first lens satisfies: L1 / R1≥0.8;

[0027] The receiving lens includes at least one second lens. The side of the second lens includes a second arc surface and a second plane. Along the first direction, the second plane is located on the side of the second lens closer to the transmitting lens. The radius of the second arc surface is a second radius R2. The distance between the second optical axis and the second plane is a second distance L2. The second lens satisfies: L2 / R2≥0.8.

[0028] Wherein, the first direction is a direction determined by one of the transmitting lens and the receiving lens pointing to the other.

[0029] In some embodiments, the lidar further includes:

[0030] The turntable, on which the light source module, the transmitting lens, the photoelectric detection module, and the receiving lens are all mounted; and

[0031] A drive module, connected to the turntable, is used to drive the turntable to rotate around a first axis;

[0032] The first optical axis is tilted relative to the first axis, and the emission field of view corresponding to the light source module is located on the same side of the first axis.

[0033] In some embodiments, the boundary of the emission field of view coincides with the first axis.

[0034] In some embodiments, the emission field of view includes a first sub-emission field of view and a second sub-emission field of view. The first sub-emission field of view is located between the first axis and the first optical axis. The second sub-emission field of view and the first sub-emission field of view are respectively located on opposite sides of the first optical axis. The field of view angle of the first sub-emission field of view is smaller than that of the second sub-emission field of view.

[0035] In some embodiments, the light source module includes a first sub-light source module and a second sub-light source module;

[0036] Both the first sub-light source module and the second sub-light source module include multiple lasers. The number of lasers in the first sub-light source module is less than the number of lasers in the second sub-light source module. The first sub-light source module is located between the first axis and the first optical axis and corresponds to the first sub-emission field of view. The second sub-light source module and the first sub-light source module are located on opposite sides of the first optical axis, and the second sub-light source module corresponds to the second sub-emission field of view.

[0037] In some embodiments, the field of view of the emission field of view is equal to 90°. Attached Figure Description

[0038] Figure 1 This is a schematic diagram of a lidar system in related technologies;

[0039] Figure 2 This is a schematic diagram of another type of lidar in related technologies;

[0040] Figure 3 This is a schematic diagram of a lidar in one embodiment of this application;

[0041] Figure 4 This is a schematic diagram showing the geometric relationship between the blind spot image height, target distance, focal length of the receiving lens, and the offset of the first and second optical axes.

[0042] Figure 5 This is a schematic diagram of the transmitting lens and the receiving lens in one embodiment of this application;

[0043] Figure 6 for Figure 5 A side view of the structure shown;

[0044] Figure 7 This is a schematic diagram of the transmitting lens and the receiving lens in another embodiment of this application;

[0045] Figure 8 for Figure 7 A side view of the structure shown;

[0046] Figure 9 A schematic diagram of a lidar in another embodiment of this application;

[0047] Figure 10 This is a schematic diagram showing the relationship between the first axis, the first optical axis, and the emission field of view in one embodiment of this application;

[0048] Figure 11 This is a schematic diagram showing the relationship between the first axis, the first optical axis, and the emission field of view in another embodiment of this application;

[0049] Figure 12 This is a schematic diagram showing the relationship between the first axis, the first optical axis, and the emission field of view in another embodiment of this application;

[0050] Figure 13 This is a schematic diagram showing the relationship between the first axis, the first optical axis, and the emission field of view in another embodiment of this application.

[0051] The annotations in the attached figures are explained as follows:

[0052] 1. LiDAR;

[0053] 10. Light source module; 11. First sub-light source module; 12. Second sub-light source module;

[0054] 20. Photoelectric detection module;

[0055] 30. Emitting lens; O1. First optical axis; 31. First lens; 311. First plane; 312. First curved surface;

[0056] 40. Receiving lens; O2. Second optical axis; 41. Second lens; 411. Second plane; 412. Second curved surface;

[0057] 50. First axis;

[0058] 60. Protective cover;

[0059] 70. Launch field of view;

[0060] 71. First sub-launch field of view; 72. Second sub-launch field of view. Detailed Implementation

[0061] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0062] In the description of this application, it should be understood that if terms such as "upper," "lower," "left," and "right" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, they are only for the convenience of describing this application 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. Therefore, the terms used to describe positional relationships in the accompanying drawings are only for illustrative purposes and should not be construed as limiting this patent. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0063] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as implying or suggesting relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0064] In the description of this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0065] LiDAR (Light Detection and Ranging) is a detection device that calculates the distance to an object by emitting a laser beam and detecting the echo signal reflected back from the object's surface. Based on whether the light source module and the photoelectric detection module emit and receive the laser beam through the same lens, LiDAR can be divided into coaxial LiDAR and off-axis LiDAR. Compared to coaxial LiDAR, off-axis LiDAR has a simpler structure and higher echo reception capability, making it a focus of research and development for many manufacturers.

[0066] However, off-axis lidar also suffers from a large size; therefore, how to reduce the overall size of lidar without affecting its detection function is a problem worth studying.

[0067] like Figure 1As shown, the off-axis lidar in the related technology includes a light source module 10', a photoelectric detection module 20', a transmitting lens 30', and a receiving lens 40'. In most products, the transmitting lens 30' and the receiving lens 40' use the same two lenses. However, in a few products, the size of the receiving lens 40' is slightly enlarged to improve the ability of the receiving lens 40' to receive echo signals, thereby improving the assembly tolerance between the receiving lens 40' and the photoelectric detection module 20' and mitigating the effect of the echo signal being offset relative to the transmitted signal.

[0068] The external dimensions of the LiDAR's light-transmitting area depend to some extent on the sum of the dimensions of the transmitting and receiving lenses. For solutions using two identical lenses in related technologies, some manufacturers will chamfer the edges of the two lenses to reduce the overall size of the LiDAR (please refer to...). Figure 2 This involves removing the area on the side of the two lenses that is close to each other and not used for light transmission; however, this optical chamfering method requires high precision, which increases the manufacturing cost of lidar and reduces its reliability.

[0069] This application provides a solution using a small-sized receiving lens to address the problem of large overall size of lidar in related technologies.

[0070] like Figure 3 As shown, the lidar 1 in this embodiment includes a light source module 10, a photoelectric detection module 20, a transmitting lens 30, and a receiving lens 40. Specifically, the light source module 10 generates detection light, and the transmitting lens 30 is located on the light-emitting side of the light source module 10, used to receive and emit the detection light. The transmitting lens 30 has a first optical axis O1. The photoelectric detection module 20 receives echo light, which is formed by the reflection of the detection light from the target object. The receiving lens 40 is located on the light-incident side of the photoelectric detection module 20, used to receive and emit the echo light to the photoelectric detection module 20. The receiving lens 40 has a second optical axis O2, and the first optical axis O1 is parallel to the second optical axis O2. The focal length of the receiving lens 40 is smaller than the focal length of the transmitting lens 30.

[0071] Assuming the lens's function remains constant, the focal length and size of the lens are positively correlated. In other words, the larger the focal length of the lens, the larger the lens size will be.

[0072] The first optical axis O1 of the transmitting lens 30 is parallel to and not collinear with the second optical axis O2 of the receiving lens 40, meaning the lidar 1 is an off-axis structure. Based on the principle of similar triangles, the light source module 10, the photoelectric detection module 20, the transmitting lens 30, and the receiving lens 40 satisfy the following relationship:

[0073] H1 / f1 = H2 / f2;

[0074] Wherein, H1 is the size of the light-emitting surface of the light source module 10 in the preset direction, H2 is the size of the photosensitive surface of the photoelectric detection module 20 in the preset direction, f1 is the focal length of the transmitting lens 30, and f2 is the focal length of the receiving lens 40.

[0075] From the above relationship, we can conclude that:

[0076] f2 = H2 * f1 / H1;

[0077] Here, 1 / H1 determines the divergence angle of the transmitting lens 30, which is usually a fixed parameter. Therefore, f2 and H2 can be reduced proportionally. That is, by reducing both f2 and H2, the similar triangle relationship between the light source module 10, the photoelectric detection module 20, the transmitting lens 30, and the receiving lens 40 can still be maintained. Simultaneously, reducing the focal length f2 of the receiving lens 40 also reduces the size of the receiving lens 40. Thus, a lidar 1 with a smaller receiving lens 40 is constructed. In this lidar 1, the focal length f2 of the receiving lens 40 is smaller than the focal length f1 of the transmitting lens 30.

[0078] In this embodiment of the lidar 1, the first optical axis O1 of the transmitting lens 30 is parallel to the second optical axis O2 of the receiving lens 40, and the focal length f2 of the receiving lens 40 is smaller than the focal length f1 of the transmitting lens 30. This makes the size of the receiving lens 40 smaller than that of the transmitting lens 30, thus creating a small-sized receiving lens 40. Therefore, compared to related technologies that use identical transmitting and receiving lenses or large-sized receiving lenses, the lidar 1 in this embodiment can reduce the external dimensions of the light-transmitting area, and consequently, the overall size of the lidar 1 can also be reduced.

[0079] It is understandable that while using a small-sized receiving lens 40, the size of the photosensitive surface of the photoelectric detection module 20 can also be reduced accordingly, so that the light source module 10, the photoelectric detection module 20, the transmitting lens 30 and the receiving lens 40 satisfy a similar triangle relationship, thereby enabling the lidar 1 to maintain normal detection function.

[0080] In addition, such as Figure 4 As shown, off-axis lidar naturally possesses a large receiving field of view at close range, corresponding to a blind zone image height h. This field of view depends on the focal length of the receiving lens 40 and the maximum image height of the photoelectric detection module, which are respectively related to the offset L of the first optical axis O1 and the second optical axis O2 (i.e., the distance between the first optical axis O1 and the second optical axis O2), the focal length f2 of the receiving lens 40, and the target distance D, that is:

[0081] h / f2 = L / D;

[0082] This formula can also be expressed as:

[0083] h = L * f² / D;

[0084] Given a fixed target distance D, the smaller the offset L of the first optical axis O1 and the second optical axis O2, and the smaller the focal length f2 of the receiving lens 40, the smaller the blind zone image height h will be.

[0085] Therefore, it can be seen that the lidar 1 in this application embodiment can achieve the same size blind zone while making the offset between the transmitting lens 30 and the receiving lens 40 smaller, the focal length of the receiving lens 40 smaller, and the size of the photoelectric detection module 20 smaller. In other words, the lidar 1 provided in this application embodiment can achieve the same size detection blind zone with a smaller volume. That is, the lidar 1 provided in this application embodiment can improve the current situation of the large overall volume of lidar 1 in related technologies.

[0086] In some embodiments, the transmitting lens 30 and the receiving lens 40 satisfy the following relationship:

[0087] 0.5≤f2 / f1≤0.9;

[0088] Where f1 is the focal length of the transmitting lens 30 and f2 is the focal length of the receiving lens 40.

[0089] If the value of f2 / f1 is less than 0.5, the aperture of the receiving lens 40 will be too small, resulting in insufficient energy received by the photoelectric detection module 20 and affecting the detection performance of the lidar 1. Conversely, if the value of f2 / f1 is greater than 0.9, the reduction in the size of the receiving lens 40 will not be significant, thus limiting the reduction in the size of the lidar 1. In this embodiment, the transmitting lens 30 and the receiving lens 40 satisfy the relationship: 0.5 ≤ f2 / f1 ≤ 0.9. This ensures that the receiving lens 40 has a sufficient aperture to guarantee that the photoelectric detection module 20 can receive enough energy, while also allowing for a relatively significant reduction in the size of the receiving lens 40, thereby achieving the effect of reducing the size of the lidar 1.

[0090] In some embodiments, the light source module 10 and the photodetector module 20 satisfy the following relationship:

[0091] H 2x <H 1x H 2y <H 1y ;

[0092] Among them, H 1x H is the dimension of the light-emitting surface of the light source module 10 along the first direction X. 1y H is the dimension of the light-emitting surface of the light source module 10 along the second direction Y. 2xH is the dimension of the photosensitive surface of the photodetector module 20 along the first direction X. 2y Let Y be the dimension of the photosensitive surface of the photodetector module 20 along the second direction Y. The first direction X is the direction determined by one of the first optical axis O1 and the second optical axis O2 pointing to the other. The second direction Y is perpendicular to both the first optical axis O1 and the first direction X. In addition, the extension direction of the first optical axis O1 is the third direction Z.

[0093] In this embodiment, the focal length f2 of the receiving lens 40 is less than the focal length f1 of the transmitting lens 30. According to the principle of similar triangles, the size H2 of the photosensitive surface of the photoelectric detection module 20 is also less than the size H1 of the emitting surface of the light source module 10. Specifically, the size H2 of the photosensitive surface along the first direction X... 2x Smaller than the dimension H of the luminous surface along the first direction X 1x The size H of the photosensitive surface along the second direction Y 2y Smaller than the dimension H of the luminous surface along the second direction Y 1y In addition, the size of the photosensitive surface along the first direction X and the second direction Y is reduced. This is partly to adapt to the change of the receiving lens 40, and partly to reduce the size of the photoelectric detection module 20, thereby further reducing the overall cost of the lidar 1.

[0094] In some embodiments, the light source module 10 and the photodetector module 20 satisfy the following relationship:

[0095] 0.5≤H 2x / H 1x ≤0.9, 0.5≤H 2y / H 1y ≤0.9;

[0096] Furthermore, H 2x With H 1x The ratio is equal to H 2y With H 1y The ratio of .

[0097] Based on the relationship 0.5 ≤ f2 / f1 ≤ 0.9 satisfying the transmitting lens 30 and receiving lens 40, in this embodiment, the light source module 10 and photoelectric detection module 20 also satisfy the relationship: 0.5 ≤ H 2x / H 1x ≤0.9, 0.5≤H 2y / H 1y ≤0.9. This allows the size of the photosensitive surface of the detection module and the focal length of the receiving lens 40 to be reduced proportionally to satisfy the similar triangle relationship.

[0098] In some of these embodiments, such as Figure 3As shown, along the extension direction of the first optical axis O1, the photoelectric detection module 20 is located on the side of the light source module 10 facing the transmitting lens 30.

[0099] Since the focal length f2 of the receiving lens 40 is less than the focal length f1 of the transmitting lens 30, the distance between the photoelectric detection module 20 and the receiving lens 40 is correspondingly less than the distance between the light source module 10 and the transmitting lens 30. Thus, with the transmitting lens 30 and the receiving lens 40 arranged side-by-side, along the extension direction of the first optical axis O1, the photoelectric detection module 20 is located on the side of the light source module 10 facing the transmitting lens 30. Compared to related technologies that use two identical lenses, in this embodiment, the position of the photoelectric detection module 20 is moved forward (towards the receiving lens 40). The space freed up by moving the photoelectric detection module 20 forward can be used to install other components in the lidar 1, further improving the space utilization of the lidar 1 or reducing its overall size.

[0100] In some embodiments, along the extension direction of the first optical axis O1, the emitting lens 30 has a first focal plane facing the light source module 10, and the receiving lens 40 has a second focal plane facing the photodetector module 20. The second focal plane is located on the side of the first focal plane facing the emitting lens 30. Typically, the emitting surface of the light source module 10 is located at the first focal plane of the emitting lens 30, and the photosensitive surface of the photodetector module 20 is located at the second focal plane of the receiving lens 40. This arrangement aims to keep the emitting lens 30 and the receiving lens 40 in a roughly parallel relative position, avoiding the receiving lens 40 being too far back relative to the emitting lens 20, which would cause the receiving field of view of the photodetector module 20 to be blocked by other components within the lidar 1; at the same time, it also allows the position of the photodetector module 20 to be moved forward relative to the light source module 10, thereby achieving the technical effects described above.

[0101] In some of these embodiments, such as Figure 5 , Figure 6 As shown, the transmitting lens 30 includes at least one first lens 31, the projection of the first lens 31 along the first optical axis O1 being circular. The receiving lens 40 includes at least one second lens 41, the projection of the second lens 41 along the second optical axis O2 being circular.

[0102] Compared to related technologies that use two identical lenses, the size of the receiving lens 40 in this embodiment is reduced, which also reduces the distance between the first optical axis O1 and the second optical axis O2. This eliminates the need for chamfering the transmitting lens 30 and the receiving lens 40. Without chamfering, the projection of the first lens 31 of the transmitting lens 30 along the first optical axis O1 is circular, and the projection of the second lens 41 along the second optical axis O2 is also circular. Since the first lens 31 and the second lens 41 remain circular, there is no need to adjust the circumferential angles of the first lens 31 and the second lens 41 during the assembly of the lidar 1. The assembly process is simpler than that of lenses with chamfered edges, which improves assembly efficiency.

[0103] In other embodiments, such as Figure 7 , Figure 8 As shown, the transmitting lens 30 includes at least one first lens 31. The side surface of the first lens 31 includes a first curved surface 312 and a first flat surface 311. Along the first direction X, the first flat surface 311 is located on the side of the first lens 31 closer to the receiving lens 40. The radius of the first curved surface 312 is a first radius R1, and the distance between the first optical axis O1 and the first flat surface 311 is a first distance L1. The first lens 31 satisfies: L1 / R1 ≥ 0.8. The receiving lens 40 includes at least one second lens 41. The side surface of the second lens 41 includes a second curved surface 412 and a second flat surface 411. Along the first direction X, the second flat surface 411 is located on the side of the second lens 41 closer to the transmitting lens 30. The radius of the second curved surface 412 is a second radius R2, and the distance between the second optical axis O2 and the second flat surface 411 is a second distance L2. The second lens 41 satisfies: L2 / R2 ≥ 0.8. Here, the first direction X is a direction defined by one of the transmitting lens 30 and the receiving lens 40 pointing to the other.

[0104] In this embodiment, the transmitting lens 30 and the receiving lens 40 can also be chamfered. The first plane 311 is the plane formed by chamfering the first lens 31, and the uncut portion of the first lens 31 has a first arc surface 312. Similarly, the second plane 411 is the plane formed by chamfering the second lens 41, and the uncut portion of the second lens 41 has a second arc surface 412. Based on this, the first lens 31 satisfies L1 / R1≥0.8, and the second lens 41 satisfies L2 / R2≥0.8. This means that the radial length of the cut-off portion does not exceed 20% of the radius of the corresponding lens. In related technologies using two identical lenses, the radial length of the cut-off portion is typically around 30% of the lens radius. In other words, compared with the lidar in related technologies, the distance between the first optical axis O1 and the second optical axis O2 in this embodiment of lidar 1 is reduced. Therefore, the amount of cutting can be relatively small when the lens is cut. This is beneficial to ensure that the lidar 1 has a small volume while allowing the transmitting lens 30 and / or receiving lens 40 to transmit light with a larger light-transmitting surface, so as to ensure that the laser beam can be transmitted and received with high energy.

[0105] In some of these embodiments, such as Figure 9 As shown, the lidar 1 also includes a turntable (not shown) and a drive module (not shown). The light source module 10, transmitting lens 30, photoelectric detection module 20, and receiving lens 40 are all mounted on the turntable. The drive module is connected to the turntable and drives the turntable to rotate around the first axis 50, so that the detection light emitted by the light source module 10 can scan the external environment of the lidar 1, and the photoelectric detection module 20 receives the corresponding echo light. Furthermore, the lidar 1 also includes a hemispherical protective cover 60, within which the drive module, light source module 10, transmitting lens 30, photoelectric detection module 20, and receiving lens 40 are all located. The protective cover 60 provides protection against collisions, dust, and water for the drive module, light source module 10, transmitting lens 30, photoelectric detection module 20, and receiving lens 40.

[0106] In this embodiment, the first optical axis O1 of the transmitting lens 20 is tilted relative to the first axis 50, and the transmitting field of view 70 corresponding to the light source module 10 is located on the same side of the first axis 50. Since the second optical axis O2 is parallel to the first optical axis O1, the second optical axis O2 of the receiving lens 40 is also tilted relative to the first axis 50. Correspondingly, the receiving field of view corresponding to the photoelectric detection module 20 is also located on the same side of the first axis 50. Since the light source module 10, the transmitting lens 30, the photoelectric detection module 20, and the receiving lens 40 all move in a circle around the first axis 50, if a portion of the transmitting field of view 70 (hereinafter referred to as the first portion for ease of explanation) crosses the first axis 50, although the first portion that crosses the first axis 50 will form a corresponding first detection area, the second detection area formed by the second portion of the transmitting field of view 70 that is mirrored with the first portion will overlap with the first detection area, thus wasting the detection field of view. In contrast, in this embodiment, the transmitting field of view 70 is located entirely on one side of the first axis 50, thus improving the above-mentioned shortcomings.

[0107] In some embodiments of this application, such as Figures 10 to 13 As shown, the boundary of the emission field of view 70 coincides with the first axis 50. Thus, the detection field of view of the lidar 1 is a continuous, nearly hemispherical field of view centered on the first axis. For example, in some application scenarios of the lidar 1, the lidar 1 can be mounted on the front end of a mobile device such as a vehicle, with the first axis 50 configured parallel to or approximately parallel to the horizontal direction. In this case, the detection field of view of the lidar 1 is a continuous detection field of view located on the front end of the mobile device. As for the size of the emission field of view corresponding to the light source module 10, it can be less than 90°, equal to 90°, or greater than 90°; this application does not specifically limit this. For example, please refer to... Figure 13 In some embodiments, the emission field of view is less than 90°, in which case the detection field of view of the lidar 1 is a field of view smaller than a hemisphere; for example, please refer to Figure 10 In some embodiments, the emission field of view is equal to 90°, in which case the detection field of view of the lidar 1 is a hemispherical field of view; for example, please refer to Figure 11 and Figure 12 In some embodiments, the transmitting field of view is greater than 90°, in which case the detection field of view of the lidar 1 is a hyperspherical field of view. It should be noted that the field of view angle of the receiving field of view corresponding to the photoelectric detection module 20 can be consistent with or slightly larger than the field of view angle of the transmitting field of view 70.

[0108] Please continue reading. Figures 10 to 13The emission field of view 70 includes a first sub-emission field of view 71 and a second sub-emission field of view 72. The first sub-emission field of view 71 is located between the first axis 50 and the first optical axis O1, and the second sub-emission field of view 72 is located on opposite sides of the first optical axis O1. Correspondingly, the receiving field of view may include a first sub-receiving field of view and a second sub-receiving field of view. The first sub-receiving field of view is located between the first axis 50 and the second optical axis O2, and corresponds to the first sub-emission field of view. The second sub-receiving field of view is located on opposite sides of the second optical axis O2, and corresponds to the second sub-emission field of view. In some embodiments, the field of view angle β of the first sub-emission field of view 71 is smaller than the field of view angle γ of the second sub-emission field of view 72, and the field of view angle of the first sub-receiving field of view is smaller than the field of view angle of the second sub-receiving field of view, for example... Figure 12 The embodiment shown is configured such that, within a preset plane, the first optical axis O1 is closer to the first axis 50 relative to the plane where the turntable is located, so as to raise the light-emitting end of the transmitting lens 30 and the light-receiving end of the receiving lens 40 by an angle α relative to the plane where the turntable is located. Since the protective cover of the lidar 1 is a hemispherical structure, the above configuration helps to reduce the dimensions of the transmitting lens 30 and the receiving lens 40 in the direction of the plane where the turntable is located, thereby facilitating the miniaturization of the lidar 1. Herein, the "preset plane" mentioned in this application means the plane determined by the first axis and the first optical axis, i.e., both the first axis and the first optical axis are located within the preset plane.

[0109] It should be understood that although the above embodiments are illustrated by taking the example that the field of view angle β of the first sub-emission field of view 71 is smaller than the field of view angle γ of the second sub-emission field of view 72, this application is not limited thereto. In other embodiments of this application, the field of view angles of the first sub-emission field of view 71 and the second sub-emission field of view 72 may also have other size relationships. For example, in some other embodiments, the field of view angle β of the first sub-emission field of view 71 and the field of view angle γ of the second sub-emission field of view 72 may also be equal; specifically, refer to Figure 10 The field of view of the launch field of view 70 is equal to 90°. The field of view angles β of the first sub-launch field of view and γ of the second sub-launch field of view are both 45°, which are equal. (See also: [reference needed]) Figure 11 The field of view of the emitted field of view is greater than 90°, and the field of view angles β of the first sub-emission field of view and γ of the second sub-emission field of view are equal and both greater than 45°. For example, in other embodiments of this application, the field of view angle β of the first sub-emission field of view 71 may also be greater than the field of view angle γ of the second sub-emission field of view 72; specifically, see [reference needed]. Figure 13 The field of view of the transmitting field of view is less than 90°, the field of view of the first sub-transmitting field of view β is equal to 45°, and the field of view of the second sub-transmitting field of view γ is less than 45°. That is, the field of view β of the first sub-transmitting field of view 71 is greater than the field of view γ of the second sub-transmitting field of view 72.

[0110] Next, we will provide supplementary explanations regarding the specific configuration of the light source module 10. Please refer to [link / reference needed]. Figure 9 The light source module 10 includes a first sub-light source module 11 and a second sub-light source module 12. The first sub-light source module 11 is located between the first axis 50 and the first optical axis O1, and corresponds to a first sub-emission field of view 71. The first sub-light source module 11 includes multiple lasers arranged from the side closest to the first optical axis along the side opposite to the first optical axis O1 (e.g., along the aforementioned second direction Y). The second sub-light source module 12 is located on both sides of the first sub-light source module 11, and corresponds to a second sub-emission field of view 72. The second sub-light source module 12 also includes multiple lasers arranged from the side closest to the first optical axis along the side opposite to the first optical axis O1 (e.g., along the aforementioned second direction Y). The light emitted from the first sub-light source module 11 forms the first sub-emission field of view 71 after passing through the emission lens 30, and the light emitted from the second sub-light source module 12 forms the second sub-emission field of view 72 after passing through the emission lens 30. In this case, the number of lasers in the first sub-light source module 11 is less than the number of lasers in the second sub-light source module 12, so the first sub-emission field of view 71 is smaller than the second sub-emission field of view 72. The photoelectric detection module 20 can adopt a similar arrangement to the light source module 10 to ensure that the detectors in the photoelectric detection module correspond one-to-one with the lasers in the light source module 10, which will not be elaborated here.

[0111] Regarding the launch field of view 70, it is worth mentioning that although the above descriptions all use the example of the launch field of view 70's boundary coinciding with the first axis 50, in other embodiments of this application, the boundary of the launch field of view 70 may not coincide with the first axis 50. This application does not specifically limit the relative positional relationship between the launch field of view 70 and the first axis 50. For example, in other embodiments of this application, the launch field of view 70 may also be entirely located between the first axis 50 and the plane where the turntable is located.

[0112] In summary, the lidar 1 provided in this application embodiment includes a light source module 10, a photoelectric detection module 20, a transmitting lens 30, and a receiving lens 40. The first optical axis O1 of the transmitting lens 30 is parallel to the second optical axis O2 of the receiving lens 40, and the focal length f2 of the receiving lens 40 is smaller than the focal length f1 of the transmitting lens 30. This results in a smaller size for the receiving lens 40 compared to the transmitting lens 30, thus creating a smaller-sized receiving lens 30. Therefore, compared to related technologies that use transmitting and receiving lenses with the same aperture and focal length, the lidar 1 in this application embodiment can reduce the size of the receiving lens 40, thereby reducing the overall size of the lidar.

[0113] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A lidar, characterized in that, include: The light source module is used to generate the probe light; A transmitting lens, located on the light-emitting side of the light source module, is used to receive the probe light and emit it. The transmitting lens has a first optical axis. A photoelectric detection module is used to receive echo light, which is formed by the detection light being reflected by the target object; as well as A receiving lens, located on the light-incident side of the photoelectric detection module, is used to receive the echo light and emit it to the photoelectric detection module. The receiving lens has a second optical axis, and the first optical axis is parallel to the second optical axis. The focal length of the receiving lens is smaller than that of the transmitting lens.

2. The lidar according to claim 1, characterized in that, The transmitting lens and the receiving lens satisfy the following relationship: 0.5≤f2 / f1≤0.9; Where f1 is the focal length of the transmitting lens and f2 is the focal length of the receiving lens.

3. The lidar according to claim 1, characterized in that, The light source module and the photoelectric detection module satisfy the following relationship: H 2x <H 1x ,H 2y <H 1y ; Among them, H 1x H represents the dimension of the light-emitting surface of the light source module along the first direction. 1y H represents the dimension of the light-emitting surface of the light source module along the second direction. 2x H represents the dimension of the photosensitive surface of the photodetector module along the first direction. 2y The first direction is the dimension of the photosensitive surface of the photodetector module along the second direction, where the first direction is the direction determined by one of the first optical axis and the second optical axis pointing to the other, and the second direction is perpendicular to the first optical axis and the first direction, respectively.

4. The lidar according to claim 3, characterized in that, The light source module and the photoelectric detection module satisfy the following relationship: 0.5≤H 2x / H 1x ≤0.9,0.5≤H 2y / H 1y ≤0.9; Furthermore, H 2x With H 1x The ratio is equal to H 2y With H 1y The ratio of .

5. The lidar according to claim 1, characterized in that, Along the extension direction of the first optical axis, the photoelectric detection module is located on the side of the light source module facing the emitting lens; and / or, Along the extension direction of the first optical axis, the emitting lens has a first focal plane facing the light source module, and the receiving lens has a second focal plane facing the photoelectric detection module, the second focal plane being located on the side of the first focal plane facing the emitting lens.

6. The lidar according to claim 1, characterized in that, The transmitting lens includes at least one first lens, the projection of which along the first optical axis is circular; The receiving lens includes at least one second lens, the projection of which along the second optical axis is circular.

7. The lidar according to claim 1, characterized in that, The transmitting lens includes at least one first lens. The side of the first lens includes a first arc surface and a first plane. Along a first direction, the first plane is located on the side of the first lens closer to the receiving lens. The radius of the first arc surface is a first radius R1. The distance between the first optical axis and the first plane is a first distance L1. The first lens satisfies: L1 / R1≥0.

8. The receiving lens includes at least one second lens. The side of the second lens includes a second arc surface and a second plane. Along the first direction, the second plane is located on the side of the second lens closer to the transmitting lens. The radius of the second arc surface is a second radius R2. The distance between the second optical axis and the second plane is a second distance L2. The second lens satisfies: L2 / R2≥0.

8. Wherein, the first direction is a direction determined by one of the transmitting lens and the receiving lens pointing to the other.

8. The lidar according to claim 1, characterized in that, The lidar also includes: The turntable, on which the light source module, the transmitting lens, the photoelectric detection module, and the receiving lens are all mounted; and A drive module, connected to the turntable, is used to drive the turntable to rotate around a first axis; The first optical axis is tilted relative to the first axis, and the emission field of view corresponding to the light source module is located on the same side of the first axis.

9. The lidar according to claim 8, characterized in that, The boundary of the emission field of view coincides with the first axis.

10. The lidar according to claim 8, characterized in that, The emission field of view includes a first sub-emission field of view and a second sub-emission field of view. The first sub-emission field of view is located between the first axis and the first optical axis. The second sub-emission field of view and the first sub-emission field of view are respectively located on both sides of the first optical axis. The field of view angle of the first sub-emission field of view is smaller than that of the second sub-emission field of view.

11. The lidar according to claim 10, characterized in that, The light source module includes a first sub-light source module and a second sub-light source module; Both the first sub-light source module and the second sub-light source module include multiple lasers. The number of lasers in the first sub-light source module is less than the number of lasers in the second sub-light source module. The first sub-light source module is located between the first axis and the first optical axis and corresponds to the first sub-emission field of view. The second sub-light source module and the first sub-light source module are located on opposite sides of the first optical axis, and the second sub-light source module corresponds to the second sub-emission field of view.

12. The lidar according to claim 8, characterized in that, The field of view of the emission field of view is equal to 90°.

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