LiDAR and vehicles

Abstract

This invention discloses a lidar and a vehicle, wherein the lidar includes: a mounting bracket; a first reflector mounted on the mounting bracket, the first reflector having a first reflective surface and a second reflective surface facing away from each other; a first driving mechanism for driving the first double-sided reflector to move, causing the normal direction of the first reflector to change periodically; a laser source for projecting laser light onto the first and second reflective surfaces; and a laser receiver for receiving the incident light from the lidar reflected by the first and second reflective surfaces. This invention can increase the field of view of the lidar.

Description

Technical Field

[0001] This invention relates to the field of radar technology, and in particular to a lidar and a vehicle. Background Technology

[0002] LiDAR (LiDAR) calculates the distance between the laser's location and the laser's reflection point by emitting laser light and receiving the reflected light. This is achieved by analyzing the time difference between the received reflected light and the emitted laser light, or the phase information of the received reflected light. By changing the laser's emission direction, the reflection point can be altered, allowing for the acquisition of distance information from different reflection points to the LiDAR location. Combined with the laser's emission angle, this information can be used to scan the environment. To change the laser's emission direction, devices such as oscillating mirrors or galvanometers are typically used. Taking an oscillating mirror as an example, the laser light first strikes the oscillating mirror, and after reflection, it exits the LiDAR. The oscillating mirror swings around its axis, changing the angle at which the laser enters the mirror, thus altering the laser's emission angle and direction. In practice, LiDAR is often mounted on moving objects to scan the environment, such as those on airplanes and cars. This causes the LiDAR's position to change, resulting in image distortion. Therefore, the faster the LiDAR completes a scan, the less distortion occurs. However, both the oscillating mirror and the galvanometer have speed limits. Exceeding these limits can damage the oscillating mirror or require higher manufacturing costs to increase the power of the drive mechanism and the strength of the connecting mechanism to maintain higher speeds. To reduce the speed of the oscillating mirror or galvanometer while increasing the scanning cycle of the lidar, the only option is to reduce the oscillation amplitude of the oscillating mirror behind the galvanometer. Reducing the oscillation amplitude, in turn, reduces the scanning range, thus decreasing the lidar's field of view. However, with the development of technologies such as autonomous driving and flying cars, there is a growing need for lidar with a wider field of view. Summary of the Invention

[0003] The main objective of this invention is to provide a lidar that increases the field of view.

[0004] To achieve the above objectives, the present invention provides a lidar comprising:

[0005] Mounting bracket;

[0006] A first reflector is mounted on the mounting bracket and has a first reflective surface and a second reflective surface facing away from each other.

[0007] A first driving mechanism is used to drive the first double-sided reflector to move, so that the normal direction of the first reflector changes periodically.

[0008] A laser source, wherein the laser source is used to project laser light onto the first reflective surface and the second reflective surface;

[0009] A laser receiver is used to receive the incident light of the lidar reflected by the first reflective surface and the second reflective surface.

[0010] Optionally, the first reflector is configured as a oscillating mirror or a galvanizing mirror.

[0011] Optionally, the first reflective surface is configured as a first high-reflectivity mirror, and the second reflective surface is configured as a second high-reflectivity mirror; the wavelength of the first high-reflectivity mirror is matched with the wavelength of the laser light source projected onto the first high-reflectivity mirror; the wavelength of the second high-reflectivity mirror is matched with the wavelength of the laser light source projected onto the second high-reflectivity mirror.

[0012] Furthermore, the lidar also includes a second reflector and a second driving mechanism. The second reflector is mounted on the mounting bracket and is used to reflect the light emitted from the first reflector. The first driving mechanism drives the first reflector to reciprocate along a first axis, and the second driving mechanism drives the second reflector to reciprocate along a second axis. The angle between the first axis and the second axis is a preset angle; or

[0013] The lidar further includes a rotating mirror and a third driving mechanism. The rotating mirror is rotatably mounted on the mounting bracket and is used to reflect the light emitted from the first reflector. The first driving mechanism drives the first reflector to reciprocate along a first axis, and the third driving mechanism drives the rotating mirror to rotate along a third axis. The angle between the first axis and the third axis is a preset angle.

[0014] The first reflector is configured as a two-dimensional galvanometer, and the first driving mechanism is used to drive the two-dimensional galvanometer to reciprocate along the fast axis and the slow axis.

[0015] Furthermore, the lidar also includes a first beam splitter and a second beam splitter. The first beam splitter is positioned upstream of the optical path of the lidar's emitted light from the first reflective surface; the second beam splitter is positioned upstream of the optical path of the lidar's emitted light from the second reflective surface. The emitted light from the laser source is split into two beams. The first beam splitter reflects one beam of emitted light from the laser source, and the second beam splitter reflects the other beam of emitted light from the laser source. The laser receiver includes a first laser receiver and a second laser receiver. The first laser receiver is positioned downstream of the incident light from the lidar via the first beam splitter; the second laser receiver is positioned downstream of the incident light from the lidar via the second beam splitter.

[0016] Optionally, the first beam splitter includes a first high-reflectivity section and a first high-transmittance section, the first high-transmittance section being disposed around the first high-reflectivity section, and the first high-reflectivity section and the first high-transmittance section being configured to match the wavelength of the laser light projected onto the first high-reflectivity section by the laser source; the second beam splitter includes a second high-reflectivity section and a second high-transmittance section, the second high-transmittance section being disposed around the second high-reflectivity section, and the second high-reflectivity section and the second high-transmittance section being configured to match the wavelength of the laser light projected onto the second high-reflectivity section by the laser source.

[0017] Optionally, the laser source includes a beam splitter and a first laser generator, wherein the beam splitter is used to split the laser beam emitted by the first laser generator.

[0018] Optionally, the beam splitter is configured as a beam splitter capable of splitting light intensity.

[0019] Optionally, the beam splitter is configured to split multiple beams of light, and the multiple beams of light split by the beam splitter have divergent exit angles.

[0020] Optionally, the laser source includes a second laser generator and a third laser generator, wherein the emitted light from the second laser generator is directed toward the first reflective surface, and the emitted light from the third laser generator is directed toward the second reflective surface.

[0021] Optionally, the wavelength of the light emitted by the second laser generator is a first preset wavelength, and the wavelength of the light emitted by the third laser generator is a second preset wavelength.

[0022] Optionally, the first preset wavelength is equal to the second preset wavelength, and the first preset wavelength is equal to 1550nm or 905nm; or

[0023] The first preset wavelength is 1550nm, and the second preset wavelength is 905nm.

[0024] Optionally, the first reflective surface is configured as a first high-reflectivity mirror, and the second reflective surface is configured as a second high-reflectivity mirror; the first high-reflectivity mirror is matched with the first preset wavelength; and the second high-reflectivity mirror is matched with the second preset wavelength.

[0025] Furthermore, the lidar also includes a first beam splitter and a second beam splitter. The first beam splitter is positioned upstream of the optical path of the lidar's emitted light on the first reflective surface; the second beam splitter is positioned upstream of the optical path of the lidar's emitted light on the second reflective surface; the first beam splitter is used to reflect the emitted light from the second laser generator, and the second beam splitter is used to reflect the emitted light from the third laser generator.

[0026] The first beam splitter includes a first high-reflectivity section and a first high-transmittance section, the first high-transmittance section being disposed around the first high-reflectivity section, and the first high-reflectivity section and the first high-transmittance section being matched with the first preset wavelength; the second beam splitter includes a second high-reflectivity section and a second high-transmittance section, the second high-transmittance section being disposed around the second high-reflectivity section, and the second high-reflectivity section and the second high-transmittance section being matched with the second preset wavelength.

[0027] The present invention also proposes a vehicle including the aforementioned lidar.

[0028] Alternatively, the vehicle is configured as a flying vehicle.

[0029] This invention improves the field of view of a lidar by providing a first reflective surface and a second reflective surface facing away from each other on a first reflector. A first driving mechanism drives the first reflector to move, causing the normal direction of the first reflector to change periodically. Since the angle of incidence is defined as the angle between the incident direction and the normal to the plane, the periodic change in the normal of the first reflector changes the incident angle of the laser, thus changing the exit angle. Each periodic change in the reflection direction of the first reflector completes one scan. Because both the first and second reflective surfaces are reflective and facing away from each other, both can serve as reflective surfaces for a single laser beam. When a laser source projects laser light onto the first and second reflective surfaces, scanning can be performed simultaneously using both surfaces. Therefore, with the same range of motion of the first reflector, the scanning angle is equal to the sum of the scanning angles of the first and second reflective surfaces. Thus, this invention doubles the field of view of the lidar without increasing the range of motion of the first reflector, thereby increasing the lidar's field of view. Attached Figure Description

[0030] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0031] Figure 1 This is a schematic diagram of the structure of an embodiment of the lidar of the present invention;

[0032] Figure 2 This is a schematic diagram of another embodiment of the lidar of the present invention;

[0033] Figure 3 for Figure 1 A schematic diagram of the structure of the first beam splitter in the embodiment;

[0034] Figure 4 This is a schematic diagram of the field of view of another embodiment of the lidar of the present invention;

[0035] Figure 5 This is a schematic diagram of the field of view of another embodiment of the lidar of the present invention.

[0036] Explanation of icon numbers:

[0037] label name label name 10 First Reflector 61 First laser generator 20 Laser receiver 62 Second laser generator 30 Rotating Mirror 63 Third laser generator 40 First beam splitter 70 Upper field of view 41 First high altitude sickness section 80 Lower field of view 42 First high-transparency section 90 Horizon 50 Second beam splitter

[0038] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0039] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0040] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0041] Furthermore, the use of terms such as "first" and "second" in this invention is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. Additionally, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. When the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed by this invention.

[0042] This invention proposes a lidar.

[0043] In an embodiment of the present invention, reference is made to Figure 1 and Figure 2 The lidar includes:

[0044] Mounting bracket;

[0045] The first reflector 10 is mounted on a mounting bracket and has a first reflective surface and a second reflective surface facing away from each other.

[0046] The first driving mechanism is used to drive the first double-sided mirror to move, so that the normal direction of the first mirror 10 changes periodically.

[0047] A laser source is used to project laser light onto the first reflective surface and the second reflective surface.

[0048] Laser receiver 20 is used to receive the incident light of the lidar reflected by the first reflective surface and the second reflective surface.

[0049] like Figure 4 or Figure 5 The upper field of view 70 and lower field of view 80 shown constitute the vertical field of view of the lidar, i.e., the field of view in the vertical direction. When the vehicle moves in a straight line at a constant speed, the intersection line of the upper field of view 70 and the lower field of view 80 is often 5° below the horizontal line 90. This is because the front of the vehicle will tilt upwards when accelerating. To avoid the upper field of view 70 failing to cover the ground near the vehicle when the front of the vehicle tilts upwards, the intersection line is made 5° below the horizontal line 90. Existing lidars often only have the aforementioned upper field of view 70. However, in the embodiment of the present invention, the first reflector 10 can be used to provide the upper field of view 70 and the lower field of view 80 scanning range for the lidar. Since the first reflector 10 has a first reflective surface and a second reflective surface facing opposite directions, the first reflective surface can be used to provide the scanning range of the upper field of view 70, and the second reflective surface can be used to provide the scanning range of the lower field of view 80. In this way, a lower field of view 80 with the same field of view angle as the upper field of view 70 can be provided. Figure 4 As shown in Figure 5, when the upper field of view is 25°, the lower field of view is also 25°. In... Figure 4 or Figure 5In the illustrated embodiment, to achieve an upper and lower field of view of 25°, i.e., a total field of view of 50°, the first reflector 10 only needs to swing with an amplitude of 12.5°. Traditional lidar, however, requires a 25° swing to achieve a total vertical field of view of 50°. Since the swing amplitude and swing frequency are mutually restrictive, for the same fixed mechanical structure, a larger swing amplitude results in a smaller swing frequency. To achieve a higher point frequency (i.e., the number of points scanned per unit time), lidar needs to increase the swing frequency. Therefore, the present invention increases the lidar's field of view while maintaining its point frequency. Essentially, the advantage of this invention is that it achieves a larger field of view with a smaller swing amplitude while maintaining the number of points scanned per unit time. Thus, when the vehicle does not require a large field of view, the swing amplitude can be reduced while increasing the swing frequency to achieve a higher point frequency scan and improve the lidar's clarity. A large field of view is particularly important for flying vehicles because the nose-end swing of a flying vehicle during deceleration and acceleration is much greater than that of a ground-based vehicle. A large field of view ensures that the flying vehicle does not lose its ability to detect the direction directly ahead during acceleration or deceleration, thus ensuring vehicle safety. Of course, this invention can also be applied to altering the horizontal field of view of a lidar. The light emitted by the lidar's laser is its output light. When the output light exits the lidar, it is reflected by an obstacle, and this reflected light enters the lidar and becomes its incident light. The lidar can have a housing that encapsulates the laser source, a first reflector 10, a mounting bracket, and a first receiver, etc. The laser receiver 20 can be housed within this housing, but its receiving window must be able to receive the incident light. Alternatively, the laser receiver 20 can be located outside the housing, simply downstream of the incident light path and facing the incident light. The structure and principle of the laser receiver 20 are also existing technologies. For example, the laser receiver 20 can be made using a photoavalanche diode, which can convert the laser signal into an electrical signal for the control system to recognize and process. The structure and principle of the laser receiver 20 will not be described in detail here.

[0050] refer to Figure 1 and Figure 2Optionally, the first reflector 10 can be configured as a swing mirror or a galvanometer. The swing mirror is a reflector driven by a mechanical structure. For example, the swing mirror can be mounted on a rotating shaft and connected to it via a motor and transmission mechanism, driving the swing mirror to reciprocate along the shaft. Because it is driven by a motor, the swing amplitude or frequency can be increased by increasing the motor power, resulting in a higher swing frequency and amplitude. The mechanical structure also has higher reliability. The driving method and structure of the swing mirror are existing technologies and will not be described in detail here. The galvanometer can be an electrostatically driven, electromagnetically driven, piezoelectrically driven, or electrothermally driven galvanometer. The driving structure of the galvanometer is existing technology and will not be described in detail here. The galvanometer has a compact structure, which is beneficial for the miniaturization of lidar. When the first reflector 10 is configured as a swing mirror, the first driving mechanism can be a motor and transmission mechanism to drive the swing mirror to swing; when the first reflector 10 is configured as a galvanometer, the first driving mechanism can be a microelectromechanical system (MEMS) to achieve electrostatic, electromagnetic, voltage, or electrothermal driving methods. The specific structure and principles of microelectromechanical systems refer to existing technologies.

[0051] refer to Figure 1 and Figure 2 Optionally, the first reflective surface is configured as a first high-reflectivity mirror, and the second reflective surface is configured as a second high-reflectivity mirror. The wavelength of the first high-reflectivity mirror is matched with the wavelength of the laser light projected onto the first high-reflectivity mirror from the laser source; the wavelength of the second high-reflectivity mirror is matched with the wavelength of the laser light projected onto the second high-reflectivity mirror from the laser source. The specific structure and principle of the high-reflectivity mirror are prior art, and high-reflectivity mirror is a well-known technical term in the art. High-reflectivity mirrors come in many categories, some of which can be designed according to the wavelength of light. For example, a metal film is coated on the surface of the mirror, the thickness of which is a specific multiple of the wavelength of the target reflected light. This allows the reflected light on both sides of the film to have the same phase at the same point in space, resulting in constructive interference and thus improving the reflectivity of the mirror surface. Of course, the coating is not limited to metal coating, and the specific structure of the high-reflectivity mirror can refer to the prior art. Since the laser source has good monochromaticity, this type of high-reflectivity mirror, which can be set according to the wavelength, can be used to improve the reflectivity of the laser, thereby reducing the loss of the emitted light from the lidar during the emission process.

[0052] refer to Figure 1 and Figure 2 Furthermore, the lidar also includes a second reflector and a second driving mechanism. The second reflector is mounted on a mounting bracket and is used to reflect the light emitted from the first reflector 10. The first driving mechanism drives the first reflector 10 to reciprocate along a first rotating axis, and the second driving mechanism drives the second reflector to reciprocate along a second rotating axis. The angle between the first and second rotating axes is a preset angle; or

[0053] The lidar also includes a rotating mirror 30 and a third driving mechanism. The rotating mirror 30 is rotatably mounted on a mounting bracket and is used to reflect the light emitted from the first reflector 10. The first driving mechanism drives the first reflector 10 to reciprocate along a first axis, and the third driving mechanism drives the rotating mirror 30 to rotate along a third axis. The angle between the first axis and the third axis is a preset angle.

[0054] The first reflector 10 is configured as a two-dimensional galvanometer, and the first drive mechanism is used to drive the two-dimensional galvanometer to reciprocate along the fast axis and the slow axis.

[0055] The specific structure of the second reflector can refer to that of the first reflector 10, and the driving structure of the second driving mechanism can also refer to that of the first driving mechanism. The first and second rotating shafts can be perpendicular, allowing the first reflector 10 to change the vertical emission direction of the laser, thus completing the vertical scanning of the lidar. The second reflector is used to change the horizontal emission direction of the laser, thus completing the horizontal scanning of the lidar. This arrangement reduces the number of structural types in the lidar, thereby reducing its structural complexity.

[0056] The rotating mirror 30 rotates continuously along its axis. The rotating mirror 30 is equipped with a reflective surface, such as... Figure 1 or Figure 2 The rotating mirror 30 shown is a triangular prism. In use, it rotates around a third axis, which is generally located on the axis of the triangular prism. This rotation causes reflections from different sides, thus changing the laser's emission direction. Similarly, the first reflector 10 can be used to change the laser's vertical emission direction to complete the vertical scanning of the lidar; the rotating mirror 30 can be used to change the laser's horizontal emission direction to complete the horizontal scanning of the lidar. The rotating mirror 30 can also be of other shapes. The specific structure of the rotating mirror 30 is prior art. The third drive mechanism, which is also prior art, can be a motor-driven mechanism to drive the rotation of the rotating mirror 30. Because the rotating mirror 30 can rotate unidirectionally without reciprocating rotation, it can achieve a higher speed, thereby increasing the scanning speed. The rotating mirror 30 uses a mechanical drive structure, which is simple, reliable, and low in cost.

[0057] The structure and driving principle of a two-dimensional galvanometer are existing technologies. A two-dimensional galvanometer can rotate simultaneously along two axes, a fast axis and a slow axis. Rotation along the fast and slow axes can change the emission direction of the laser in the horizontal and vertical directions, respectively, thereby enabling the lidar to scan in both directions. Since only one two-dimensional galvanometer is needed to complete both horizontal and vertical scanning, it is beneficial for the miniaturization of lidar. Furthermore, utilizing the double-sided nature of the two-dimensional galvanometer can simultaneously increase the field of view in both directions.

[0058] refer to Figure 1 and Figure 2 Furthermore, the lidar also includes a first beam splitter 40 and a second beam splitter 50. The first beam splitter 40 is positioned upstream of the optical path of the emitted light from the lidar on the first reflective surface; the second beam splitter 50 is positioned upstream of the optical path of the emitted light from the lidar on the second reflective surface. The emitted light from the laser source is split into two beams. The first beam splitter 40 is used to reflect one beam of emitted light from the laser source, and the second beam splitter 50 is used to reflect the other beam of emitted light from the laser source. The laser receiver 20 includes a first laser receiver and a second laser receiver. The first laser receiver is positioned downstream of the optical path of the incident light from the lidar on the first beam splitter 40; the second laser receiver is positioned downstream of the optical path of the incident light from the lidar on the second beam splitter 50. The first beam splitter 40 and the second beam splitter 50 can be semi-reflective mirrors, and the structure and principle of semi-reflective mirrors refer to existing technologies. The light emitted from the laser source is reflected by the first beam splitter 40 and then enters the first reflective surface; it is reflected by the second beam splitter 50 and then enters the second reflective surface. Therefore, the first beam splitter 40 and the second beam splitter 50 can control the incident direction of the first and second reflective surfaces, respectively, making the optical path design convenient. Due to the principle of optical path reversibility, the output light and incident light of the lidar have the same optical path. Therefore, the reflected light path of the output light on the first beam splitter 40 coincides with the incident light path on the first beam splitter 40; the reflected light path of the output light on the second beam splitter 50 coincides with the incident light path on the second beam splitter 50. Since the relative spatial relationship between the laser source, the first beam splitter 40, and the second beam splitter 50 can remain unchanged, the optical path of the incident light of the lidar can also remain unchanged relative to the laser source. Therefore, it is only necessary to fix the positions of the first and second laser receivers relative to the laser source and make their receiving windows face the incident light of the lidar to achieve a good reception effect of the incident light.

[0059] refer to Figures 1 to 3Optionally, the first beam splitter 40 includes a first high-reflectivity section 41 and a first high-transmittance section 42, with the first high-transmittance section 42 surrounding the first high-reflectivity section 41. The wavelengths of the first high-reflectivity section 41 and the first high-transmittance section 42 are matched with the wavelengths of the laser light projected onto the first high-reflectivity section 41 by the laser source. The second beam splitter 50 includes a second high-reflectivity section and a second high-transmittance section, with the second high-transmittance section surrounding the second high-reflectivity section. The wavelengths of the second high-reflectivity section and the second high-transmittance section are matched with the wavelengths of the laser light projected onto the second high-reflectivity section by the laser source. The first high-reflectivity section 41 is located at the center of the first beam splitter 40, allowing the emitted light from the laser source to be aligned with the first high-reflectivity section 41. Since the laser spot is small, the first high-reflectivity section 41 can be set to a size similar to the laser spot to reflect the laser spot. The structure of the high-reflectivity section refers to the structure of high-reflectivity mirrors in the prior art, which can reduce the loss during laser transmission. Since the emitted light from the lidar is reflected as divergent light upon encountering an obstacle, the incident light from the lidar is also divergent. The first high-transmittance section 42 can transmit the incident light from the lidar, allowing the first laser receiver to receive as much incident light as possible, thereby improving the lidar's ability to sense the incident light. Similarly, the second high-reflection section and the second high-transmittance section of the second beam splitter 50 can reduce the loss during laser transmission and allow the second laser receiver to receive as much incident light as possible, respectively. The structures of the first high-transmittance section 42 and the second high-transmittance section are based on high-transmittance lenses in the prior art. High-transmittance lenses are common knowledge in the art; for example, a coating can be applied to the lens surface, with a coating thickness that is a specific multiple of the wavelength of the target transmitted light, thereby increasing the lens's transmittance. Alternatively, the transmittance can be increased by improving the properties of the lens material itself. Both the first beam splitter 40 and the second beam splitter 50 can be configured as plane mirrors.

[0060] refer to Figure 1 Optionally, the laser source includes a beam splitter and a first laser generator 61. The beam splitter is used to split the laser beam emitted by the first laser generator 61. The structure and principle of the beam splitter are existing technologies. By using a beam splitter to split the laser source, only one laser generator is needed to obtain two beams of light, which can then be projected onto the first and second reflective surfaces. This reduces the number of laser generators required, thereby reducing the complexity of the lidar and facilitating production and maintenance.

[0061] refer to Figure 1Optionally, the beam splitter can be configured as a beam splitter capable of splitting light intensity. Lasers capable of splitting light intensity are existing technology. For example, a Y-type fiber can be used for beam splitting, where the incident light from the laser generator is connected to the input end of the Y-type fiber, and the output end of the Y-type fiber has multiple beam splitting fibers. By simply dividing the output end into two groups of different numbers of fibers, two beams of different intensities can be produced. The structure of the Y-type fiber is existing technology, and its structure and principle will not be elaborated here. Since light typically weakens with increasing propagation distance, a higher light intensity allows it to travel a greater distance and be detected by the laser receiver 20 through reflection. However, when the light intensity is insufficient, the reflected light reaching the laser receiver 20 has too low an intensity to be detected. Therefore, a strong light intensity can increase the detection range of the lidar. Typically, the upper field of view 70 of a vehicle requires a relatively long detection range, while the lower field of view 80 does not require a very long detection range. Therefore, it can be used as follows... Figure 5 As shown, by using a beam splitter that can split light intensity, the upper field of view 70 can be split to obtain more light intensity, thereby increasing the detection distance, while the lower field of view 80 can be split to obtain less light intensity, thereby saving energy consumption. Therefore, a beam splitter that can split light intensity can make the distribution of laser light intensity more reasonable.

[0062] refer to Figure 1 Optionally, the beam splitter is configured to split multiple beams, and the multiple beams split by the beam splitter have divergent exit angles. This allows for the acquisition of lasers incident on the first and second reflective surfaces from different angles, thereby enabling scanning in multiple directions and further improving the laser's field of view; or it can simultaneously scan in multiple directions, thereby increasing the point frequency of the lidar.

[0063] refer to Figure 2 Optionally, the laser source includes a second laser generator 62 and a third laser generator 63. The emitted light from the second laser generator 62 is directed towards the first reflective surface, and the emitted light from the third laser generator 63 is directed towards the second reflective surface. The dual laser generator configuration helps to increase the power of the lidar, thereby increasing its detection range and also improving the flexibility of lidar design.

[0064] refer to Figure 1 and Figure 2Optionally, the wavelength of the light emitted by the second laser generator 62 is a first preset wavelength, and the wavelength of the light emitted by the third laser generator 63 is a second preset wavelength. The first and second preset wavelengths can be the same, allowing the first beam splitter 40 and the second beam splitter 50 to have identical structures, as well as the first and second reflective surfaces. This improves the reflectivity of the first high-reflectivity section 41, the second high-reflectivity section, the first high-reflectivity mirror, and the second high-reflectivity mirror, and also improves the transmittance of the first high-transmittance section 42 and the second high-transmittance section to the laser. This simplifies the structure of the lidar and helps reduce costs.

[0065] refer to Figure 1 and Figure 2 Optionally, the first preset wavelength is equal to the second preset wavelength, and the first preset wavelength is equal to 1550nm or 905nm; or

[0066] The first preset wavelength is 1550nm, and the second preset wavelength is 905nm.

[0067] 1550nm lasers experience lower propagation loss in the atmosphere, enabling longer detection ranges. 905nm lasers are less expensive. When the first preset wavelength equals the second preset wavelength (1550nm), the detection range of the lidar can be increased; when the first preset wavelength equals the second preset wavelength (905nm), the cost of the lidar can be reduced. When the first preset wavelength is 1550nm and the second preset wavelength is 905nm, the 1550nm laser can be used to detect the upper field of view (70°) while the 905nm laser can be used to detect the lower field of view (80°), thus achieving... Figure 5 The distribution of detection ranges shown balances detection range with cost.

[0068] refer to Figure 1 and Figure 2 Optionally, the first reflective surface is configured as a first high-reflectivity mirror, and the second reflective surface is configured as a second high-reflectivity mirror; the first high-reflectivity mirror is matched with a first preset wavelength; the second high-reflectivity mirror is matched with a second preset wavelength. When the first preset wavelength and the second preset wavelength are equal, the first and second high-reflectivity mirrors can be configured with the same structure; when the first preset wavelength is not equal to the second preset wavelength, the first and second high-reflectivity mirrors should be configured for the first and second preset wavelengths respectively, for example, they can be coated with metal films of a specific multiple of the thickness of the first or second preset wavelength. The structure of high-reflectivity mirrors designed for different wavelengths of light is prior art.

[0069] refer to Figure 1 and Figure 2Furthermore, the lidar also includes a first beam splitter 40 and a second beam splitter 50. The first beam splitter 40 is positioned upstream of the light output from the lidar on the first reflective surface; the second beam splitter 50 is positioned upstream of the light output from the lidar on the second reflective surface. The first beam splitter 40 is used to reflect the light output from the second laser generator 62, and the second beam splitter 50 is used to reflect the light output from the third laser generator 63.

[0070] The first beam splitter 40 includes a first high-reflectivity section 41 and a first high-transmittance section 42, the first high-transmittance section 42 being disposed around the first high-reflectivity section 41, and the first high-reflectivity section 41 and the first high-transmittance section 42 being matched with a first preset wavelength; the second beam splitter 50 includes a second high-reflectivity section and a second high-transmittance section, the second high-transmittance section being disposed around the second high-reflectivity section, and the second high-reflectivity section and the second high-transmittance section being matched with a second preset wavelength.

[0071] By setting corresponding first high reflectivity section 41, first high transmittance section 42, second high reflectivity section, and second high transmittance section for the first preset wavelength and the second preset wavelength, the flexibility of lidar design can be improved, the loss in laser propagation can be reduced, thereby increasing the energy efficiency of lidar or increasing the detection range.

[0072] The present invention also proposes a vehicle that includes a lidar. The specific structure of the lidar is as described in the above embodiments. Since the vehicle adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be described in detail here.

[0073] The lidar in the embodiment of the technical solution of the present invention can be used as a front radar of a vehicle. It can be installed on the roof of the vehicle along the upper edge of the windshield to detect the situation in front of the vehicle. It can be used in autonomous vehicles as radar of the autonomous driving system.

[0074] Optionally, the vehicle can be configured as a flying vehicle. The flying vehicle can be a vehicle using a quadcopter structure; it can also be a vehicle using wings and a turbine engine; or it can be a vehicle capable of both land travel and flight. Because flying vehicles need to utilize their own power to control acceleration and deceleration, they are more likely to tilt forward or backward. To ensure the lidar's detection capability in front of the vehicle, it is necessary to... Figure 4 or Figure 5 The downward field-of-view detection capability shown requires a larger vertical field of view. The lidar in the embodiment of the present invention has a larger field of view, making it suitable for application on flying vehicles.

[0075] The above description is merely a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made using the contents of the present invention's specification and drawings under the inventive concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A lidar, characterized in that, include: Mounting bracket; A first reflector is mounted on the mounting bracket and has a first reflective surface and a second reflective surface facing away from each other. A first driving mechanism is used to drive the first reflector to move, so that the normal direction of the first reflector changes periodically. A laser source, wherein the laser source is used to project laser light onto the first reflective surface and the second reflective surface; A laser receiver, wherein the laser receiver is used to receive the incident light of the lidar reflected by the first reflective surface and the second reflective surface; The lidar further includes a second reflector and a second driving mechanism. The second reflector is mounted on the mounting bracket and is used to reflect the light emitted from the first reflector. The first driving mechanism drives the first reflector to reciprocate along a first axis, and the second driving mechanism drives the second reflector to reciprocate along a second axis. The angle between the first axis and the second axis is a preset angle. The lidar further includes a rotating mirror and a third driving mechanism. The rotating mirror is rotatably mounted on the mounting bracket and is used to reflect the light emitted from the first reflector. The first driving mechanism drives the first reflector to reciprocate along a first axis, and the third driving mechanism drives the rotating mirror to rotate along a third axis. The angle between the first axis and the third axis is a preset angle. The first reflector is configured as a two-dimensional galvanometer, and the first driving mechanism is used to drive the two-dimensional galvanometer to reciprocate along the fast axis and the slow axis.

2. The lidar as described in claim 1, characterized in that, The first reflector is configured as a oscillating mirror or a galvanizing mirror.

3. The lidar as described in claim 1, characterized in that, The first reflective surface is configured as a first high-reflectivity mirror, and the second reflective surface is configured as a second high-reflectivity mirror; the wavelength of the first high-reflectivity mirror is matched with the wavelength of the laser light source projected onto the first high-reflectivity mirror; the wavelength of the second high-reflectivity mirror is matched with the wavelength of the laser light source projected onto the second high-reflectivity mirror.

4. The lidar as described in claim 1, characterized in that, The lidar further includes a first beam splitter and a second beam splitter. The first beam splitter is positioned upstream of the light path of the lidar's emitted light from the first reflective surface; the second beam splitter is positioned upstream of the light path of the lidar's emitted light from the second reflective surface. The emitted light from the laser source is split into two beams. The first beam splitter reflects one beam of emitted light from the laser source, and the second beam splitter reflects the other beam of emitted light from the laser source. The laser receiver includes a first laser receiver and a second laser receiver. The first laser receiver is positioned downstream of the light path of the lidar's incident light from the first beam splitter; the second laser receiver is positioned downstream of the light path of the lidar's incident light from the second beam splitter.

5. The lidar as described in claim 4, characterized in that, The first beam splitter includes a first high-reflectivity section and a first high-transmittance section, the first high-transmittance section being disposed around the first high-reflectivity section, and the first high-reflectivity section and the first high-transmittance section being configured to match the wavelength of the laser light projected onto the first high-reflectivity section by the laser source; the second beam splitter includes a second high-reflectivity section and a second high-transmittance section, the second high-transmittance section being disposed around the second high-reflectivity section, and the second high-reflectivity section and the second high-transmittance section being configured to match the wavelength of the laser light projected onto the second high-reflectivity section by the laser source.

6. The lidar as described in claim 1, characterized in that, The laser source includes a beam splitter and a first laser generator, wherein the beam splitter is used to split the laser beam emitted by the first laser generator.

7. The lidar as described in claim 6, characterized in that, The beam splitter is configured to split light intensity.

8. The lidar as described in claim 6, characterized in that, The beam splitter is configured to split multiple beams of light, and the multiple beams of light split by the beam splitter have divergent exit angles.

9. The lidar as described in claim 1, characterized in that, The laser source includes a second laser generator and a third laser generator. The emitted light from the second laser generator is directed toward the first reflective surface, and the emitted light from the third laser generator is directed toward the second reflective surface.

10. The lidar as described in claim 9, characterized in that, The wavelength of the light emitted by the second laser generator is a first preset wavelength, and the wavelength of the light emitted by the third laser generator is a second preset wavelength.

11. The lidar as described in claim 10, characterized in that, The first preset wavelength is equal to the second preset wavelength, and the first preset wavelength is equal to 1550nm or 905nm; or The first preset wavelength is 1550nm, and the second preset wavelength is 905nm.

12. The lidar as described in claim 10, characterized in that, The first reflective surface is configured as a first high-reflectivity mirror, and the second reflective surface is configured as a second high-reflectivity mirror; the first high-reflectivity mirror is matched with the first preset wavelength; and the second high-reflectivity mirror is matched with the second preset wavelength.

13. The lidar as described in claim 10, characterized in that, The lidar further includes a first beam splitter and a second beam splitter. The first beam splitter is positioned upstream of the optical path of the lidar's emitted light on the first reflective surface. The second beam splitter is positioned upstream of the optical path of the lidar's emitted light on the second reflective surface. The first beam splitter is used to reflect the emitted light from the second laser generator, and the second beam splitter is used to reflect the emitted light from the third laser generator. The first beam splitter includes a first high-reflectivity section and a first high-transmittance section, the first high-transmittance section being disposed around the first high-reflectivity section, and the first high-reflectivity section and the first high-transmittance section being matched with the first preset wavelength; the second beam splitter includes a second high-reflectivity section and a second high-transmittance section, the second high-transmittance section being disposed around the second high-reflectivity section, and the second high-reflectivity section and the second high-transmittance section being matched with the second preset wavelength.

14. A vehicle, characterized in that... Including the lidar as described in any one of claims 1 to 13.

15. The vehicle as claimed in claim 14, characterized in that, The vehicle is configured as a flying vehicle.

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