Laser radar

Abstract

The invention discloses a laser radar which comprises a transmitting assembly, a shaping assembly, a rotatable reflecting mirror, a light filtering cover, an extinction body and a receiving assembly. Measurement light beams emitted by the emission assembly are emitted out of the laser radar through the shaping assembly, the rotatable reflector and the filter cover, and the extinction body is used for absorbing at least part of the measurement light beams reflected by the filter cover, so that the measurement light beams reflected by the filter cover in the laser radar are reduced, and the measurement light beams received by the receiving assembly in the laser radar are reduced. Ghost images are suppressed, and the ranging precision of the laser radar is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of lidar, and in particular to suppressing lidar ghost images. Background Art

[0002] A lidar can emit a laser beam with a specific wavelength and in a specific direction, collect the energy of the returned beam, and measure the return time of the echo signal to calculate the distance to the object being measured.

[0003] For a lidar with a coaxial transmitting system and receiving system, it is difficult to suppress the beam that is reflected multiple times inside the lidar and returns to the detector, resulting in the formation of ghost images from the internal reflection signals of the lidar, covering the echo signals of nearby targets, leading to a large detection blind area of the lidar, or affecting the accuracy of distance measurement, etc. Summary of the Invention

[0004] Aiming at the above problems existing in the prior art, the present invention provides a lidar to reduce the interference of the internal reflection energy of the lidar on the measurement result and improve the accuracy of distance measurement.

[0005] To achieve the above object, the present invention provides a lidar, including: a transmitting component, a shaping component, a rotatable mirror, a filter cover, an extinction body, and a receiving component;

[0006] The transmitting component is used to emit a measurement beam;

[0007] The receiving component is used to receive an echo beam, and the echo beam is a measurement beam reflected by the object being measured;

[0008] The shaping component is used to shape the measurement beam emitted by the transmitting component, and the rotatable mirror is used to reflect the shaped measurement beam towards a preset direction, so that the reflected measurement beam propagates along the preset direction and passes through the filter cover;

[0009] The rotatable mirror is further used to reflect the echo beam towards the shaping component, and the shaping component is further used to shape the echo beam and shoot the shaped echo beam towards the receiving component;

[0010] The extinction body is used to absorb at least part of the measurement beam reflected by the filter cover.

[0011] Optionally, for any ray of the measurement beam reflected by the inner surface of the filter cover, the ray has a first optical path distance D1 between the rotatable mirror and the filter cover, and the first optical path distance D1 is the distance between the incident point of the ray on the rotatable mirror and the incident point of the ray on the filter cover;

[0012] The light has a second optical path distance D2 located between the filter cover and the extinction body. The second optical path distance D2 is the distance between the incident point of the light on the filter cover and the incident point of the light on the extinction body, and D1:D2 = 10:(1-9).

[0013] Optionally, the extinction body includes an extinction part provided with an extinction surface for receiving and absorbing at least part of the measurement beam reflected by the filter cover. Optionally, a light absorption material is provided on the extinction surface.

[0014] Optionally, the extinction surface extends circumferentially around the axis of the filter cover, and the extension angle of the extinction surface in the circumferential direction around the axis of the filter cover is 240°-360°.

[0015] Optionally, the extinction surface has a line M intersecting with any plane where the axis of the filter cover is located, and the angle b between the line M and the axis of the filter cover is 0°-45°.

[0016] Optionally, the lidar includes a fixed base and a motor. The motor is fixed on the fixed base, and the rotatable mirror is connected to the motor. The motor is used to drive the rotatable mirror to rotate.

[0017] The extinction body includes at least one fixing part connected to the extinction part, and the fixing part is directly or indirectly connected to the fixed base.

[0018] Optionally, the motor includes a support body fixedly connected to the fixed base, and the fixing part is fixedly connected to the support body.

[0019] Optionally, the filter cover is of a hollow structure and includes a filter side wall, and the angle between the filter side wall and the axis of the filter cover is 5°-45°.

[0020] Optionally, the shaping component includes a shaping lens for shaping the measurement beam emitted by the emitting component, shaping the echo beam, and shooting the shaped echo beam towards the receiving component.

[0021] Optionally, at least part of the emitting component is located between the shaping lens and the receiving component.

[0022] Optionally, the shaping component includes a first shaping lens and a second shaping lens. The first shaping lens is used to shape the measurement beam emitted by the emitting component, and the second shaping lens is used to shape the echo beam and shoot the shaped echo beam towards the receiving component. The optical axis of the first shaping lens is coaxial with the optical axis of the second shaping lens.

[0023] Optionally, the first shaping lens and at least a part of the transmitting assembly are located between the rotatable mirror and the receiving assembly.

[0024] Optionally, a through hole is provided on the second shaping lens, the through hole penetrates the second shaping lens along the optical axis direction of the second shaping lens, and at least a part of the transmitting assembly is located in the through hole.

[0025] Optionally, the transmitting assembly includes a light source and a columnar accommodating body, the light source is located in the columnar accommodating body, the first shaping lens is located in the columnar accommodating body, and at least a part of the columnar accommodating body is located in the through hole.

[0026] Optionally, the first shaping lens and at least a part of the transmitting assembly are located between the rotatable mirror and the second shaping lens.

[0027] Optionally, the transmitting assembly includes at least one light source, and the receiving assembly includes at least one photodetector.

[0028] The present invention has the following beneficial effects:

[0029] A lidar is provided, including: a transmitting assembly, a shaping assembly, a rotatable mirror, a filter cover, an extinction body, and a receiving assembly. The measurement beam emitted by the transmitting assembly is emitted from the lidar through the shaping assembly, the rotatable mirror, and the filter cover. The extinction body can absorb at least a part of the measurement beam reflected by the filter cover, reduce the measurement beam reflected by the filter cover inside the lidar, thereby reducing the measurement beam inside the lidar received by the receiving assembly, suppressing ghost images, improving the ranging accuracy of the lidar, especially improving the measurement result of the lidar for a short-distance object, reducing the detection blind area of the lidar caused by ghost images, and especially improving the measurement effectiveness and measurement accuracy of the lidar for a short-distance object. Description of the Drawings

[0030] In order to more clearly illustrate the technical solutions of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0031] Figure 1 is a schematic structural diagram of a lidar provided according to the present invention;

[0032] Figure 2 is an assembled structural diagram of a lidar provided according to the present invention;

[0033] Figure 3 It is a schematic optical path diagram of the measurement beam reflected by the extinction body;

[0034] Figure 4 It is another schematic structural diagram of the lidar provided according to the present invention;

[0035] Figure 5 It is Figure 4 A schematic assembly structure diagram of the lidar shown;

[0036] Figure 6 It is another schematic structural diagram of the lidar provided according to the present invention;

[0037] Figure 7 It is a schematic structural diagram of an extinction body provided according to the present invention;

[0038] Figure 8 It is another schematic structural diagram of an extinction body provided according to the present invention. Detailed implementation manners

[0039] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0040] As Figure 1-8 shown, the present invention provides a lidar, which includes a transmitting assembly 10, a shaping assembly 12, a rotatable reflector 13, a filter cover 2, an extinction body 3, and a receiving assembly 14. This lidar is preferably a coaxial lidar.

[0041] The transmitting assembly 10 is used to emit a measurement beam. Specifically, the transmitting assembly 10 emits a measurement beam towards the shaping assembly 12.

[0042] The receiving assembly 14 is used to receive the echo beam, and the echo beam is the measurement beam reflected by the object to be measured. After the measurement beam is reflected by the object to be measured, at least part of the reflected measurement beam returns to the lidar along the emission path, and this part of the reflected measurement beam is the echo beam. The receiving assembly 14 includes a photodetector, and the photodetector is a single device or an array-arranged device, such as APD, SiPM.

[0043] The shaping assembly 12 is used to shape the measurement beam emitted by the transmitting assembly 10, collimate the measurement beam, and project the shaped measurement beam onto the rotatable reflector 13.

[0044] The rotatable mirror 13 is used to reflect the shaped measurement beam towards a preset direction, so that the reflected measurement beam propagates along the preset direction and passes through the filter cover 2, thereby enabling measurement of the object to be measured along the preset direction. The rotatable mirror 13 can rotate to reflect the measurement beam towards different directions, realizing radar measurement and recording of the entire circle of point clouds.

[0045] Optionally, the rotatable mirror 13 is a plane mirror, a galvanometer mirror or a rotating mirror.

[0046] Optionally, as Figure 2 shown, the lidar includes a motor 42, the rotatable mirror 13 is connected to the motor 42, and the motor 42 can drive the rotatable mirror 13 to rotate, so that the mirror can reflect the measurement beam towards different directions. Specifically, the motor 42 is connected to a driving connecting member 43, the driving connecting member 43 is connected to the rotatable mirror 13, and the motor 42 drives the driving connecting member 43 to rotate, thereby driving the rotatable mirror 13 to rotate.

[0047] The rotatable mirror 13 is also used to reflect the echo beam towards the shaping component 12. Specifically, the echo beam passes through the filter cover 2 and enters the lidar and then shoots towards the rotatable mirror 13. The rotatable mirror 13 reflects the echo beam towards the shaping component 12. The shaping component 12 shapes the echo beam to make the echo beam focused, and shoots the shaped echo beam towards the receiving component 14, so that the echo beam can be imaged in the receiving component 14.

[0048] An extinction body 3 is provided inside the lidar. The extinction body 3 is used to absorb at least part of the measurement beam reflected by the filter cover 2. The measurement beam passes through the filter cover 2 and shoots out of the lidar to the outside. Most of the measurement beams shooting towards the filter cover 2 pass through the filter cover 2 and shoot out towards the outside of the lidar. However, part of the measurement beam is reflected by the surface of the filter cover 2 when incident on the filter cover 2 and remains inside the lidar. At least part of the part of the measurement beam is received by the receiving component 14 during propagation, forming a ghost image. By providing the above-mentioned extinction body 3, the measurement beam reflected by the filter cover 2 can be absorbed, the beam amount can be reduced, the ghost image can be suppressed, thereby improving the ranging accuracy of the lidar, especially improving the measurement result of the lidar for a nearby object, reducing the detection blind area of the lidar caused by the ghost image, and especially improving the measurement effectiveness and measurement accuracy of the lidar for a nearby object.

[0049] In an alternative embodiment, for any ray of the measurement beam reflected by the inner surface of the filter cover 2, the ray has a first optical path distance D1 between the rotatable mirror and the filter cover, and the first optical path distance D1 is the distance between the incident point of the ray on the rotatable mirror and the incident point of the ray on the filter cover. The ray has a second optical path distance D2 between the filter cover and the extinction body 3, and the second optical path distance D2 is the distance between the incident point of the ray on the filter cover and the incident point of the ray on the extinction body. Exemplarily, the second optical path distance D2 is the distance between the incident point of the ray on the filter cover and the incident point of the ray on the extinction surface of the extinction body, D1 > D2. Preferably, D1:D2 = 10:(1-9), especially D1:D2 = 10:(2-7). For example, the ratio of D1:D2 is 4:3, 2:1 or 3:1. Thus, a smaller optical path distance is set between the filter cover and the extinction body, so that a smaller optical path distance is provided between the filter cover and the shaping assembly 12. In particular, on the optical path of the beam diffusely reflected by the extinction body propagating towards the receiving assembly 14, a smaller optical path distance is provided between the filter cover and the shaping assembly. The beam diffusely reflected by the extinction body has a larger incident angle when incident on the shaping assembly, thereby enabling an increase in the amount of the beam diffusely reflected by the extinction body blocked by the transmitting assembly, and further reducing the unwanted measurement beam received by the receiving assembly 14.

[0050] In an alternative embodiment, the extinction body 3 includes an extinction portion provided with an extinction surface 31 for receiving at least part of the measurement beam reflected by the filter cover 2.

[0051] Specifically, the filter cover 2 includes an inner surface and an outer surface. The inner surface faces the interior of the lidar, and the outer surface faces the exterior of the lidar. Both the inner surface and the outer surface are smooth surfaces, such as smooth optical surfaces. The measurement beam enters the filter cover 2 from the inner surface of the filter cover 2 and passes through the filter cover 2, and part of the measurement beam is reflected by the inner surface of the filter cover 2.

[0052] For any ray of the measurement beam reflected by the inner surface of the filter cover, the plane where the incident ray and the reflected ray of the ray are located is the reflection plane of the ray. The extinction surface 31 has a line segment L intersecting with the reflection plane, and the line segment L is a straight line segment or a curved line segment. The extinction surface 31 is arranged such that the reflected ray of any ray of the measurement beam reflected by the inner surface of the filter cover intersects with the line segment L. Thus, the extinction surface can directly cover all the measurement beams reflected by the inner surface of the filter cover, which is beneficial for the extinction surface to receive and absorb the measurement beams reflected by the filter cover.

[0053] Preferably, for a measurement beam incident on the inner surface of the filter cover along any preset direction, the extinction surface 31 is arranged such that the reflected ray of any ray in the measurement beam reflected by the inner surface of the filter cover intersects the line segment L. Exemplarily, the rotatable mirror 13 can reflect the shaped measurement beam in different directions so that the reflected measurement beam propagates along the preset direction. All the preset directions corresponding to the measurement beam form a measurement direction set. For a measurement beam incident on the inner surface of the filter cover along any direction in the measurement direction set, the extinction surface is arranged such that the reflected ray of any ray in the measurement beam reflected by the inner surface of the filter cover intersects the line segment L.

[0054] Optionally, a light-absorbing material is provided on the extinction surface 31. The light-absorbing material includes graphite, carbon black or other light-absorbing materials. Exemplarily, a light-absorbing layer is provided on the extinction surface. The light-absorbing layer includes the light-absorbing material, and the light-absorbing layer is applied to the extinction surface by spraying, coating or other means. In an alternative embodiment, the manufacturing material of the extinction body 3 includes a light-absorbing material.

[0055] Optionally, the extinction surface is a rough surface or a diffuse reflection surface.

[0056] Optionally, as Figure 2 such as 7, Figure 8 As shown, the extinction surface 31 extends circumferentially around the axis of the filter cover. The extension angle of the extinction surface in the circumferential direction around the axis of the filter cover is 240° - 360°, preferably 270° - 360°. Thus, the extinction surface can receive the detection beams reflected at different circumferential positions of the filter cover.

[0057] Optionally, the lidar includes a fixed base 41, and the motor 42 is fixed to the fixed base. The extinction body 3 includes at least one fixing part 32. The fixing part 32 is connected to the extinction part. The fixing part 32 and the extinction part are integrally formed, welded or screwed. The fixing part 32 is directly or indirectly connected to the fixed base 41.

[0058] Optionally, the extinction body 3 includes a fixing part 32. At least part of the fixing part continuously extends in the circumferential direction around the axis of the filter cover. The fixing part 32 is provided with a plurality of connecting parts 33. The fixing part 32 is fixedly connected to the motor and / or the fixed base 41 through the connecting parts 33.

[0059] Optionally, the light extinction body 3 includes a plurality of fixing parts 32 which are arranged at intervals on the light extinction part. The fixing parts 32 are provided with 1-3 connecting parts 33, and the fixing parts 32 are fixedly connected to the motor and / or the fixing base 41 through the connecting parts 33.

[0060] Optionally, the connecting part 33 is arranged as a threaded hole or a clamping connecting part.

[0061] Optionally, the motor 42 includes a support body 44 which is provided with a threaded hole or a clamping body. Thus, the fixing part 32 and the support body 44 are connected by a bolt, or the fixing part 32 and the support body are connected by clamping. Exemplarily, the support body is the housing of the motor.

[0062] Optionally, the fixing base 41 is provided with a threaded hole or a clamping body, and the fixing part 32 and the fixing base 41 are connected by a bolt, or the fixing part 32 and the fixing base 41 are connected by clamping.

[0063] Optionally, as Figure 7 、 Figure 8 shown, the light extinction body 3 includes a positioning member 34 which is located on the light extinction part or the fixing part 32, preferably on the inner side of the light extinction part or the inner side of the fixing part 32. The lidar includes a limiting part which is located on the support body 44 or the fixing base 41. The limiting part is matched with the positioning member so that the light extinction body 3 is positioned by the positioning member.

[0064] Optionally, the positioning member 33 is arranged as a positioning plate which includes a positioning plane perpendicular to the axis of the filter cover. The limiting part is arranged as a limiting groove or a limiting plane. The limiting groove includes a limiting side wall perpendicular to the axis of the filter cover, and the limiting plane is perpendicular to the axis of the filter cover. The positioning plane of the positioning plate abuts against the limiting side wall or the limiting plane of the limiting groove.

[0065] Optionally, the positioning member 33 is arranged as a positioning protrusion, and at least part of the positioning protrusion is located in the limiting groove or abuts against the limiting plane.

[0066] In an alternative embodiment, as Figure 2 、 Figure 5 shown, the filter cover 2 is of a hollow structure. The filter cover 2 includes a filter side wall, and the inner surface and the outer surface of the filter side wall respectively form the inner surface and the outer surface of the filter cover 2.

[0067] Optionally, the filter sidewall is axially inclined relative to the filter cover 2. Specifically, the measurement beam is incident on the filter sidewall of the filter cover 2 along a preset direction and passes through the filter sidewall. The preset direction is substantially perpendicular to the axis of the filter cover 2. By axially inclining the filter sidewall relative to the filter cover 2, the incident angle of the measurement beam on the filter sidewall deviates from the normal, and the propagation direction of the measurement beam after being reflected by the filter sidewall deviates from the preset direction, facilitating the extinction ring to receive the measurement beam reflected by the filter sidewall.

[0068] Optionally, the included angle a between the filter sidewall and the axis of the filter cover 2 is 5° - 45°, so that the filter sidewall has a sufficient inclination degree to ensure that the extinction ring receives all the reflected measurement beams, effectively suppressing internal ghost images, and avoiding the extinction ring blocking the echo beam, resulting in a weakening of the echo energy. At the same time, it avoids the overall machine size being large and the transmittance being reduced due to the excessive inclination angle of the filter sidewall.

[0069] Preferably, the included angle a between the filter sidewall and the axis of the filter cover 2 is 18° - 35°, for example, 10°, 15°, 20° or 30°.

[0070] Optionally, the extinction surface 31 of the extinction body 3 has a line M that intersects any plane where the axis of the filter cover lies, and the line M is parallel to the axis of the filter cover, thereby reducing the processing difficulty and forming cost of the extinction body; or, the line M is inclined in the inclined direction of the filter sidewall to facilitate the extinction surface 31 to receive and absorb the detection beam reflected by the filter cover.

[0071] Optionally, 0° ≤ b ≤ 2a is satisfied between the included angle a and the included angle b.

[0072] Optionally, the included angle b between the line M and the axis of the filter cover is 0° - 45°. In an optional embodiment, as Figure 1 、 Figure 2 shown, the shaping component 12 includes a shaping lens, and the shaping lens is used to shape the measurement beam emitted by the emitting component 10 to collimate the measurement beam. At the same time, the shaping lens is also used to shape the echo beam to focus the echo beam and direct the shaped echo beam to the receiving component 14. Thus, the shaping lens serves as both an emission collimating lens and a receiving focusing lens at the same time, and the emission optical path and the receiving optical path of the lidar are coaxial.

[0073] The shaping lens can be a single lens lens or a combination of lens lenses for shaping, and the combination of lens lenses is used to achieve shaping of the measurement beam and shaping of the echo beam.

[0074] Optionally, the shaping lens is a spherical lens, an aspherical lens or a cylindrical lens.

[0075] Optionally, the transmitting assembly 10 includes a light source 101 and a transmitting mirror 102. The light source 101 is configured to generate a measurement beam, and the transmitting mirror 102 reflects the measurement beam generated by the light source 101 toward a preset transmitting direction, that is, reflects the measurement beam toward the shaping lens, so that the measurement beam sequentially passes through the shaping lens and the rotatable mirror and exits from the lidar.

[0076] In an alternative embodiment, at least a part of the transmitting assembly 10 is located between the shaping lens and the receiving assembly 14. Specifically, at least a part of the measurement beam received by the extinction surface is absorbed by the extinction surface, and at the same time, the extinction surface diffusely reflects a part of the received measurement beam (i.e., the measurement beam incident on the extinction surface). The part of the measurement beam reflected by the extinction surface returns along the original path and propagates to the receiving system. At least a part of the transmitting assembly 10 is located on the optical path between the shaping lens and the receiving assembly 14. Thus, the transmitting assembly 10 can block the measurement beam propagating toward the receiving assembly 14 through the shaping lens, further reducing the measurement beam received by the receiving assembly 14, and minimally affecting the receiving assembly 14's reception of the echo beam, which can effectively suppress ghost images, improve ranging accuracy, and particularly can reduce the short-range ranging blind area of the lidar, with low cost and simple structure. There are also other rays inside the lidar that are reflected by the light shield toward the rotatable mirror after multiple reflections and propagate to the receiving assembly 14 through the shaping assembly 12 and are received by the receiving assembly 14, interfering with the ranging result of the lidar. The transmitting assembly 10 can also block this part of the rays, thereby improving the measurement accuracy of the lidar.

[0077] In an alternative embodiment, as Figures 4-6 shown, the shaping assembly 12 includes a first shaping lens 121 and a second shaping lens 122. The first shaping lens 121 is configured to shape the measurement beam emitted by the transmitting assembly 10 to collimate the measurement beam. The second shaping lens 122 is configured to shape the echo beam to focus the echo beam and direct the shaped echo beam toward the receiving assembly 14. Thus, the echo beam is reflected by the rotatable mirror and then directed toward the second shaping lens 122, shaped by the second shaping lens 122, and then directed toward the receiving assembly 14 and received by the receiving assembly 14. Wherein, the optical axis of the first shaping lens 121 is coaxial with the optical axis of the second shaping lens 122, so that the transmitting optical path and the receiving optical path of the lidar are coaxial.

[0078] The first shaping lens may be a single lens element for shaping or a combination of lens elements, and the combination of lens elements is used to achieve shaping of the measurement beam.

[0079] The second shaping lens may be a single lens element or a combination of lens elements for shaping, and the combination of lens elements is used to achieve shaping of the echo beam.

[0080] Optionally, the first shaping lens 121 is a spherical lens, an aspherical lens, or a cylindrical lens. Optionally, the second shaping lens 122 is a spherical lens, an aspherical lens, or a cylindrical lens.

[0081] In an optional embodiment, the first shaping lens 121 and at least a part of the transmitting assembly 10 are located between the rotatable mirror and the receiving assembly 14. Thus, the first shaping lens 121 and the transmitting assembly 10 are on the optical path between the rotatable mirror and the receiving assembly 14, and the transmitting assembly 10 can block at least a part of the measurement beam reflected by the rotatable mirror and propagating towards the receiving assembly 14 and other interference beams inside the lidar, further reducing the measurement beam and other interference beams inside the lidar received by the receiving assembly 14, and minimally affecting the reception of the echo beam by the receiving assembly 14, hardly affecting the reception of the receiving assembly 14, being able to effectively suppress ghost images, improve the ranging accuracy and precision, especially can reduce the near - range blind area of the lidar, with low cost and simple structure.

[0082] In an optional embodiment, as Figure 4 、 Figure 5 shown, a through - hole is provided on the second shaping lens 122, and the through - hole penetrates the second shaping lens 122 along the optical axis direction of the second shaping lens 122, and at least a part of the transmitting assembly 10 is located in the through - hole. Thus, the transmitting assembly 10 can block the measurement light and other interference light inside the lidar that are reflected by the rotatable mirror and propagate towards the receiving assembly 14, reducing the volume of the lidar.

[0083] Preferably, the axis of the through - hole is coaxial with the optical axis of the second shaping lens 122. In other alternative embodiments, the distance between the axis of the through - hole and the optical axis of the second shaping lens 122 is less than half of the aperture of the through - hole, especially less than 1 / 3 of the aperture of the through - hole.

[0084] Optionally, the transmitting assembly 10 includes a light source 101 and a hollow cylindrical housing, the light source 101 is located inside the cylindrical housing, and at least a part of the cylindrical housing is located in the through - hole.

[0085] Specifically, the cylindrical housing includes a side wall, one end of the cylindrical housing is provided with an end wall, the other end includes an opening, the light source 101 is provided on the end wall, the side wall and the end wall of the cylindrical housing are light - impermeable, and the measurement beam generated by the light source 101 propagates towards the outside of the cylindrical housing through the opening.

[0086] Optionally, the first shaping lens 121 is located in the columnar housing. Optionally, the first shaping lens 121 is located within the columnar housing and fixed to the side wall of the columnar housing, or the first shaping lens 121 is fixed at the opening of the columnar housing. In an alternative embodiment, the first shaping lens 121 is located between the columnar housing and the rotatable mirror.

[0087] Optionally, as Figure 6 shown, the first shaping lens 121 and at least part of the emitting assembly 10 are located between the rotatable mirror and the second shaping lens 122. Thus, the emitting assembly 10 can block the measurement light and other interfering light inside the lidar that propagate from the rotatable mirror towards the second shaping lens 122 and the receiving assembly 14, reducing the measurement light and other interfering light inside the lidar received by the receiving assembly 14. Optionally, the first shaping lens 121 is fixed to the emitting assembly 10, and the first shaping lens 121 can also be fixed inside the lidar in other ways.

[0088] In an alternative embodiment, a through hole is provided on the second shaping lens 122, and the first shaping lens 121 and at least part of the emitting assembly 10 are located between the second shaping lens 122 and the receiving assembly 14. Specifically, the measurement beam emitted by the emitting assembly 10 passes through the through hole on the second shaping lens 122 towards the rotatable mirror after being shaped by the first shaping lens 121. The emitting assembly 10 can block the measurement light and other interfering light inside the lidar that propagate from the rotatable mirror towards the receiving assembly 14, reducing the measurement light and other interfering light inside the lidar received by the receiving assembly 14.

[0089] In an optional embodiment, the emitting assembly 10 includes at least one light source 101, and the receiving assembly 14 includes at least one photodetector. Exemplarily, the emitting assembly 10 includes a plurality of light sources 101, such as 3 - 10 light sources, and the receiving assembly 14 includes a plurality of photodetectors, such as 3 - 10 photodetectors, and the number of light sources is the same as the number of photodetectors.

[0090] The above-disclosed are only several preferred embodiments of the present invention. Of course, the scope of the rights of the present invention cannot be limited thereby. Therefore, equivalent changes made according to the claims of the present invention still fall within the scope covered by the present invention.

Claims

1. A lidar, characterized in that, it includes: a transmitting component (10), a shaping component (12), a rotatable mirror (13), a filter cover (2), an extinction body (3), and a receiving component (14); the transmitting component (10) is used for transmitting a measurement beam; the receiving component (14) is used for receiving an echo beam, and the echo beam is the measurement beam reflected by the object to be measured; the shaping component (12) is used for shaping the measurement beam transmitted by the transmitting component (10), and the rotatable mirror (13) is used for reflecting the shaped measurement beam towards a preset direction, so that the reflected measurement beam propagates along the preset direction and passes through the filter cover (2); the rotatable mirror (13) is further used for reflecting the echo beam towards the shaping component (12), and the shaping component (12) is further used for shaping the echo beam and shooting the shaped echo beam towards the receiving component (14); the extinction body (3) is used for absorbing at least part of the measurement beam reflected by the filter cover (2).

2. The lidar according to claim 1, characterized in that, for any ray of the measurement beam reflected by the inner surface of the filter cover (2), the ray has a first optical path distance D1 between the rotatable mirror (13) and the filter cover (2), and the first optical path distance D1 is the distance between the incident point of the ray on the rotatable mirror (13) and the incident point of the ray on the filter cover (2); the ray has a second optical path distance D2 between the filter cover (2) and the extinction body (3), and the second optical path distance D2 is the distance between the incident point of the ray on the filter cover (2) and the incident point of the ray on the extinction body (3), and D1:D2 = 10:(1 - 9).

3. The lidar according to claim 1 or 2, characterized in that, the extinction body (3) includes an extinction part, and the extinction part is provided with an extinction surface (31), and the extinction surface (31) is used for receiving and absorbing at least part of the measurement beam reflected by the filter cover (2).

4. The lidar according to claim 3, characterized in that, the extinction surface (31) extends along the circumferential direction around the axis of the filter cover, and the extension angle of the extinction surface in the circumferential direction around the axis of the filter cover is 240° - 360°.

5. The lidar according to claim 3, characterized in that, the extinction surface (31) has a line M intersecting with any plane where the axis of the filter cover is located, and the included angle b between the line M and the axis of the filter cover is 0° - 45°.

6. The lidar according to claim 3, characterized in that, the lidar includes a fixed base (41) and a motor (42), the motor is fixed on the fixed base, the rotatable mirror (13) is connected to the motor (42), and the motor (42) is used for driving the rotatable mirror (13) to rotate; The light extinction body (3) includes at least one fixing part (32), the fixing part (32) is connected to the light extinction part, and the fixing part (32) is directly or indirectly connected to the fixing base body (41).

7. The lidar according to claim 3, wherein, the motor includes a support body (43), the support body (43) is fixedly connected to the fixing base body (41), and the fixing part (32) is fixedly connected to the support body (43).

8. The lidar according to claim 1 or 2, wherein, the filter cover (2) is a hollow structure, the filter cover (2) includes a filter side wall, and the included angle between the filter side wall and the axis of the filter cover (2) is 5°-45°.

9. The lidar according to claim 1 or 2, wherein, the shaping assembly (12) includes a shaping lens, the shaping lens is used for shaping the measurement beam emitted by the emitting assembly (10), shaping the echo beam, and shooting the shaped echo beam towards the receiving assembly (14).

10. The lidar according to claim 9, wherein, at least part of the emitting assembly (10) is located between the shaping lens and the receiving assembly (14).

Images