Optical components for scanning LiDAR systems

Abstract

The optical assembly (207) includes a first optical element having a wedge prism (216). The first optical element is rotatable about a first axis (217) and is configured to receive a light beam (140b) at a first surface (214) of the first optical element and refract the light beam (140b) to a second surface (218) of the first optical element, and the light beam (140c) exits the first optical element at the second surface. It further includes a second optical element (220). The second optical element is spaced apart from the first optical element and is positioned to receive the light beam (140c) exiting the first optical element. The second optical element (220) is rotatable about a second axis (222) and is configured to refract the light beam (140c) at a first surface (224) of the second optical element and reflect the light beam (140d) by a reflective surface (226) of the second optical element before the light beam (140e) exits the second optical element.

Description

Technical Field

[0001] The present disclosure generally relates to optical components for use in optical detection and ranging, or light detection and ranging (LiDAR) systems, and more particularly, to embodiments of optical components, systems, and methods of using the same. Background Art

[0002] LiDAR (light detection and ranging, or, laser imaging, detection, and ranging) technology involves systems and methods for detecting and measuring distances by scanning an object (e.g., a target or an obstacle) with a laser and measuring the reflection of the laser with a sensor. The difference in the laser return time and wavelength can then be used to create a 3-D representation of the object. LiDAR technology has been widely used. For example, by working with various types of sensors including LiDAR technology, autonomous driving technology can sense the surrounding environment and generate real-time instructions to safely drive a movable object, such as an autonomous vehicle, with little or no human interaction. An autonomous vehicle can be equipped with one or more sensors to collect information from the environment, such as radar, LiDAR, sonar, cameras, global positioning system (GPS), inertial measurement unit (IMU), and / or odometer, etc. Based on various sensing data obtained from one or more sensors, an autonomous vehicle needs to determine its real-time position and generate instructions for navigation.

[0003] With the development of LiDAR technology, there is a need for a more space-saving, less complex, and more cost-effective optical component and an effective method of using the same.

[0004] Disclosure

[0005] According to an embodiment of the present disclosure, there is provided an optical component for guiding a light beam to scan an environment to detect one or more objects in the environment. The optical component includes a first optical element that is rotatable about a first axis and is configured to receive a light beam on a first surface of the first optical element, refract the light beam through a second surface of the first optical element, and the light beam exits the first optical element at the second surface; and a second optical element that is spaced apart from the first optical element and is rotatable about a second axis, and the second optical element is positioned to reflect the light beam to the environment through a reflective surface of the second optical element to detect the one or more objects.

[0006] There is also provided a rotatable scanner for guiding a light beam to scan an environment to detect one or more objects in the environment. The rotatable scanner includes: an optical assembly, the optical assembly including: a reflective optical element that is rotatable about a first axis and is configured to reflect the light beam into the environment through a first side of a reflective surface; and a balance element, the balance element including: a first surface that is attached to the reflective surface of the reflective optical element at a second side opposite to the first side of the reflective surface, and a second surface that is connected to an object that is configured to adjust the weight of the balance element during rotation about the first axis to balance the optical assembly.

[0007] There is also provided a method for guiding a light beam to scan an environment to detect one or more objects in the environment. The method includes rotating a first optical element about a first axis and rotating a second optical element about a second axis, the first optical element being spaced apart from the second optical element; guiding the light beam from the first optical element to a reflective surface of the second optical element; and reflecting the light beam through the reflective surface to transmit into the environment.

[0008] There is also provided a LiDAR (light detection and ranging, or, laser imaging, detection, and ranging) system, including: a light source configured to emit a pulsed laser beam; a scanning optical assembly configured to guide the pulsed laser beam to scan an environment to detect one or more objects in the environment, the scanning optical assembly including: a first optical element that is rotatable about a first axis and is configured to receive the light beam at a first surface of the first optical element, refract the light beam through a second surface of the first optical element, the light beam leaving the first optical element at the second surface; and a second optical element spaced apart from the first optical element and rotatable about a second axis, the second optical element being positioned to reflect the light beam through a reflective surface of the second optical element into the environment to detect the one or more objects; a receiver configured to receive a return beam reflected by the one or more objects in the environment via the scanning optical assembly.

[0009] There is also provided a LiDAR system, comprising: a light source configured to emit pulsed laser beams; a scanning optical assembly configured to direct the pulsed laser beams to scan an environment to detect one or more objects in the environment, the scanning optical assembly comprising: a reflective optical element rotatable about a first axis and configured to reflect the beam to the environment through a first side of a reflective surface; and a balance element comprising: a first surface attached to the reflective surface of the reflective optical element at a second side opposite to the first side of the reflective surface, and a second surface connected to an object configured to adjust the weight of the balance element during rotation about the first axis to balance the optical assembly; a receiver configured to receive one or more return beams reflected by the one or more objects in the environment via the scanning optical assembly.

[0010] There is also provided a movable platform, comprising: an optical assembly located on the movable platform and configured to direct a beam to scan an environment to detect one or more objects in the environment, the optical assembly comprising: a first optical element rotatable about a first axis and configured to receive the beam at a first surface of the first optical element and refract the beam through a second surface of the first optical element, the beam exiting the first optical element at the second surface; and a second optical element spaced apart from the first optical element and rotatable about a second axis, the second optical element positioned to reflect the beam to the environment through a reflective surface of the second optical element to detect the one or more objects; a propulsion system configured to propel the movable platform in the environment.

[0011] It should be understood that the foregoing general description and the following detailed description are merely exemplary and explanatory and are not restrictive of the content to be protected by the present disclosure. Other features and advantages of the present disclosure will become apparent by reading the specification, the claims and the drawings. Description of the Drawings

[0012] Figure 1A A schematic diagram of an exemplary scanning LiDAR system according to an embodiment of the present disclosure is shown.

[0013] Figure 1B It shows for an embodiment of the present disclosure Figure 1A a block diagram of a system of a circuit of a LiDAR system.

[0014] Figure 1CShows a schematic diagram of a scanning LiDAR system on a movable platform according to some embodiments of the present disclosure.

[0015] Figure 1D Shows an exemplary scanning pattern of a scanning LiDAR system according to an embodiment of the present disclosure. Figure 1A

[0016] Figure 1E And Figure 1F Shows an exemplary scanning pattern of a scanning LiDAR system according to an embodiment of the present disclosure. Figure 1A

[0017] Figure 2 Shows a schematic diagram of an exemplary scanning LiDAR system according to an embodiment of the present disclosure.

[0018] Figure 3A And Figure 3B Shows a schematic diagram of an exemplary scanning LiDAR system according to an embodiment of the present disclosure.

[0019] Figure 4 Shows a schematic diagram of an exemplary scanning LiDAR system according to an embodiment of the present disclosure.

[0020] Figures 5A - 5D Shows a schematic diagram of various optical components of an exemplary scanning LiDAR system according to an embodiment of the present disclosure.

[0021] Figure 6A And Figure 6B Shows a schematic diagram of an exemplary scanning LiDAR system according to an embodiment of the present disclosure.

[0022] Figure 6C And Figure 6D Shows a schematic diagram of an exemplary housing for accommodating one or more optical elements of a scanning LiDAR system according to an embodiment of the present disclosure.

[0023] Figure 7A Shows a schematic diagram of an exemplary scanning LiDAR system according to an embodiment of the present disclosure.

[0024] Figure 7B And Figure 7C Shows a schematic diagram of exemplary optical elements of a scanning LiDAR system according to an embodiment of the present disclosure.

[0025] Figure 8 Shows a schematic diagram of an exemplary scanning LiDAR system according to an embodiment of the present disclosure.

[0026] Figures 9A - 9ESchematic diagrams of ranging modules for various embodiments of a scanning LiDAR system according to embodiments of the present disclosure are shown respectively.

[0027] Figures 10A - 10C show schematic diagrams of a housing including an optical element attached to a balancing element in a front view (Figure 10A), a right view (Figure 10B), and a top view (Figure 10C) according to embodiments of the present disclosure.

[0028] Figures 11A - 11C show schematic diagrams of a housing including an optical element attached to a balancing element in a front view (Figure 11A), a right view (Figure 11B), and a top view (Figure 11C) according to embodiments of the present disclosure.

[0029] Figures 12A - 12C show schematic diagrams of a housing including an optical element attached to a balancing element in a front view (Figure 12A), a right view (Figure 12B), and a top view (Figure 12C) according to embodiments of the present disclosure.

[0030] Figures 13A and 13B show schematic diagrams of a polyhedral housing in a front view (Figure 13A) and a top view (Figure 13B) according to embodiments of the present disclosure.

[0031] Figure 14A 、 14B 、15A, 15B, 16A, 16B, 17A, 17B, 18A, 18B, 19A, and 19B show exemplary scanning patterns generated by various LiDAR systems according to embodiments of the present disclosure.

[0032] Figure 20 、 21 、22, and 23 show schematic diagrams of various embodiments of a scanning module including an optical element and a balancing element according to embodiments of the present disclosure.

[0033] Figure 24 A flowchart of an exemplary method for guiding a beam to scan an environment to detect one or more objects in the environment according to embodiments of the present disclosure is shown.

[0034] Figure 25A A first optical element and a second optical element having respective axes of rotation according to embodiments of the present disclosure are shown.

[0035] Figure 25B The incident angle between a beam and the normal to the surface of the first optical element according to embodiments of the present disclosure is shown.

[0036] Figure 26 A three - dimensional view of a first optical element and a second optical element having respective axes of rotation according to embodiments of the present disclosure is shown.

[0037] Figures 27A - 27CShows possible orientations of a second optical element according to an embodiment of the present disclosure.

[0038] Figure 28 Shows parameters that can be used to control an optical element and a light source according to an embodiment of the present disclosure.

[0039] Figures 29A - 29D Shows possible scanning patterns according to an embodiment of the present disclosure.

[0040] Figure 30A -30C shows how the scanning pattern according to an embodiment of the present disclosure is affected by the tilt angle of a reflecting element.

[0041] Figure 31 Shows how the scanning pattern according to an embodiment of the present disclosure is affected by the relative rotational speed of an optical element. Detailed Description

[0042] The following will be described in detail with reference to the accompanying drawings. Where possible, the same reference numerals refer to the same or similar components. Although several exemplary embodiments are described herein, modifications, adaptations, and other implementations are possible. For example, components shown in the drawings may be replaced, added, or modified. Therefore, the following detailed description is not limited to the disclosed embodiments and examples, but the appropriate scope is defined by the appended claims.

[0043] The optical assemblies provided by various embodiments of the present disclosure can be applied to imaging devices, object detection devices, and / or distance measurement or ranging devices. For example, various embodiments of the optical assembly can be applied to electronic devices such as lidar or laser distance measurement devices. In some embodiments, the distance measurement device can be used to sense external environmental information, such as distance information, azimuth angle information, reflection intensity information, velocity information, etc. of one or more objects detected in the environment. In some embodiments, the distance measurement device can measure the distance between a detected object and the distance measurement device by, for example, detecting the light propagation time between the object and the distance measurement device based on time-of-flight (TOF) measurement. In some other embodiments, the distance measurement device can also measure the distance between a detected object and the distance measurement device by other techniques, such as distance measurement methods based on phase shift measurement, frequency shift measurement, or any other suitable method. It should be understood that the specification, the drawings, and the examples are considered to be only examples for illustrative purposes and are not meant to be restrictive.

[0044] In some embodiments, a scanning LiDAR system may include a distance measurement device using a coaxial optical path, wherein a beam emitted by a light source of the distance measurement device shares at least a portion of the optical path in the distance measurement device with a beam reflected by one or more objects in the environment and returned to the distance measurement device. For example, a sequence of laser pulses may be emitted by a transmitter or light source and emitted through a scanning module including optical components to change the propagation direction of the laser pulses. The laser pulses reflected by one or more detected objects may pass through the optical components of the scanning module and be received by a receiver.

[0045] In some other embodiments, a scanning LiDAR system may include a distance measurement device using an off-axis optical path, wherein a beam emitted by a light source of the distance measurement device and a beam reflected by one or more objects and returned to the distance measurement device are transmitted along different optical paths in the distance measurement device, respectively.

[0046] It should be understood that the embodiments of the optical components, distance measurement devices, and LiDAR systems of the present disclosure use coaxial optical paths as examples for illustrative purposes and are not meant to be limiting. The various embodiments of the optical components, distance measurement devices, and LiDAR systems discussed herein may also use off-axis optical paths.

[0047] Figure 1A A schematic diagram of an exemplary scanning LiDAR system 100 according to an embodiment of the present disclosure is shown. In some embodiments, the scanning LiDAR system 100 is capable of rotating 360°. In some embodiments, a 360° mechanical scanning (or rotating) LiDAR system 100 may use a multi-line (e.g., 16, 24, 128, or more lines) light source to emit beams to achieve a suitable point cloud pattern. The cost of such a multi-line LiDAR system may be high, and the assembly process is complex. In some embodiments, the scanning LiDAR system 100 may use fewer lines, such as 6 or fewer, or a single light source line. For example, some embodiments of the present disclosure provide a mechanical scanning LiDAR system with fewer or single light source lines, which includes a combination of a first optical element (e.g., a prism) and a second optical element (e.g., a mirror or a prism including a reflective surface). When the first optical element and the second optical element rotate (e.g., together or separately), the reflective surface rotates around a corresponding axis while reflecting the beam. When the reflective surface rotates, the reflection of the beam can scan multiple directions, such as including a range of 360°, without having to use a large number of light sources in the system. Therefore, a 360° stereoscopic scanning effect can be achieved with fewer light sources, lower cost, and a simpler LiDAR system.

[0048] In some embodiments, the LiDAR system 100 includes a ranging module 104 (e.g., a distance measurement module) and a scanning module 106. In some embodiments, the ranging module 104 may be configured to emit a beam 138a, receive a returned beam 142d, and convert the returned beam 142d into an electrical signal. In some embodiments, the ranging module 104 includes a light source 110 configured to emit the beam 138a, an optical element provided as a reflector 112, an optical element provided as a collimating element 114, a receiver 134 configured to receive the reflected beam (referred to herein as the returned beam 142d), a control circuit configured to control the light emission of the light source 110 and the light reception of the receiver 134, and a TOF processor 132 configured to calculate the range of the detected object using TOF technology based on the time interval between the emitted beam 138a and the detected returned beam 142d and the speed of light. The LiDAR system 100 may be a single-station scanning LiDAR system, where the light source and the receiver are relatively close to each other, and the outgoing beam and the returned beam may be aligned or share one or more coaxial optical paths.

[0049] In some embodiments, the reflector 112 (e.g., including a mirror) transmits the beam 138a from the light source 110 through the central transmission region of the reflector 112 to the collimating element 114. In some embodiments, the collimating element 114 may be provided as a collimating lens for collimating the beam 138a received from the reflector 112 and converging the returned beam 142c received from the scanning module 106 to the reflector 112.

[0050] In some embodiments, the scanning module 106 may be positioned on the outgoing optical path of the ranging module 104 and configured to generate a scanning beam 138d, e.g., as an outgoing beam derived from the beam 138b received from the ranging module 104, e.g., a 360° scanning beam, and project the scanning beam 138d onto the environment to be scanned. The scanning module 106 may also project the returned beam 142a onto the collimating element 114 of the ranging module 104 to converge to the reflector 112.

[0051] In some embodiments, the scanning module 106 may include an optical assembly 107, and the optical assembly 107 includes at least one optical element for changing the propagation path of the light beam 138b received from the ranging module 104. For example, the path-changing optical element of the scanning module 106 may change the propagation path of the light beam 138b by reflection, refraction, diffraction, and / or any combination thereof. Thus, for example, the path-changing optical element of the scanning module 106 may include a lens, a mirror, a prism, a grating, a liquid crystal, an optical phased array, or any combination of these optical elements. In some embodiments, at least a portion of at least one path-changing optical element is movable, for example, driven by a drive module to move, and the movable path-changing optical element may reflect, refract, or diffract the light beam 138b in different directions at different times. In some embodiments, a plurality of path-changing optical elements of the scanning module 106 may rotate or vibrate about a common axis, and each rotating or vibrating optical element may be used to continuously change the propagation path of the light beam 138b. In some embodiments, a plurality of path-changing optical elements of the scanning module 106 may rotate at different rotational speeds, or vibrate at different speeds. In some embodiments, the path-changing optical elements of the scanning module 106 may rotate at the same rotational speed. In some embodiments, a plurality of path-changing optical elements of the scanning module 106 may rotate about different axes. In some embodiments, a plurality of path-changing optical elements of the scanning module 106 may rotate in the same direction or in different directions. The plurality of path-changing optical elements may vibrate in the same direction or in different directions. It should be understood that the various embodiments described herein are illustrative examples and are not meant to be restrictive.

[0052] In some embodiments as Figure 1A shown, the optical assembly 107 may include a first optical element configured as a prism 116. The prism 116 may be driven by a driver 126 (e.g., a motor) to rotate about an axis 118 to project the light beam 138b collimated by the collimating element 114 in different directions as the prism 116 rotates. In some embodiments, the prism 116 has a thickness that varies along at least one radial direction. In some embodiments, the prism 116 includes a wedge prism that aligns the light beam 138b collimated by the collimating element 114 through a first surface 116-1 and refracts the aligned light beam through a second surface 116-2.

[0053] In some embodiments, the optical assembly 107 may further include Figure 1AA second optical element, which is set as a reflector 120 (also referred to as a reflective optical element) in the [device], serves as another path-changing optical element. The reflector 120 can be driven by a driver 128 (e.g., including a motor) to rotate around an axis 122, so as to project a light beam 138c received from the prism 116 in different directions when the reflector 120 rotates. In an embodiment, the axis 122 and the axis 118 are the same axis or different axes. In some embodiments, the reflector 120 includes a mirror or an optical element (e.g., a prism, such as a wedge prism or a triangular prism) that includes a reflective surface. In some embodiments, in addition to the prism 116 and the reflector 120, the optical assembly 107 may further include an optical element. The additional optical element can be a prism, a reflector, or any other suitable optical element, and can be driven by an additional driver to rotate, vibrate, or move in any suitable manner.

[0054] In some embodiments, the drivers 126 and 128 can be controlled by a controller 130 to drive the prism 116 and the reflector 120 to rotate around the axes 118 and 122 respectively, for projecting the light beam 138b received from the ranging module 104 in different directions to scan the environment around the LiDAR system 100. In some Figure 1A embodiments as shown, the prism 116 and the reflector 120 can be driven by different drivers to have different rotation speeds and / or different rotation directions, so as to project the light beam 138b received from the ranging module 104 to a larger spatial range in the environment. In some other embodiments, the prism 116 and the reflector 120 can be driven by the same driver to have the same rotation speed and / or the same rotation direction. In some embodiments, the rotation speeds of the prism 116 and the reflector 120 can be determined according to the areas and patterns expected to be scanned in the environment respectively. The drivers 126 and 128 can include motors or other drivers.

[0055] In some embodiments, the optical assembly 107 is contained within a transparent housing 124. In some Figure 1A embodiments as shown, the LiDAR system 100 uses a coaxial optical path. In some other embodiments, the LiDAR system 100 can also use an off-axis optical path. In some cases, the transparent housing 124 can include a transmission region and a modulation region. The modulation region can modulate the outgoing path of the incident light as needed to expand the field of view (FOV) upward or downward in the vertical direction, and / or expand the FOV left or right in the horizontal direction.

[0056] In some embodiments, a special optical element is provided, which is used to avoid distance attenuation caused by beam divergence. For example, when the transparent housing 124 is cylindrical or conical, the special optical element can be a cylindrical lens. In some embodiments, the special optical element can be located on one side close to the light-emitting surface of the second optical element 120, so that the beam reflected by the second optical element 120 can enter the special optical element. For example, the special optical element can be located between the second optical element 120 and the transparent housing 124. In some embodiments, the special optical element can be located on one side close to the light-incident surface of the second optical element 120, so that the beam propagating through the special optical element can enter the second optical element 120. For example, the special optical element can be located between the second optical element 120 and the first optical element 116. In some embodiments, the special optical element can be configured to rotate together with the second optical element 120.

[0057] In some embodiments, one or more optical elements of the LiDAR system 100 on the beam propagation paths for propagating the light beams 138a, 138b, 138c, and 138d, for example, can be coated with a filter layer, or a filter can be provided on the beam propagation path of the LiDAR system 100 to allow light of certain wavelength bands corresponding to the light beam 138a emitted by the light source 110 to pass through, while reflecting light of other wavelength bands, so as to reduce the noise caused by ambient light to the receiver 134.

[0058] In some embodiments, the light source 110 can be used to emit a sequence of light pulses, such as a sequence of laser pulses. In some embodiments, the light source 110 can be a pulsed laser diode, which is configured to emit the light beam 138a as a pulsed laser beam. For example, the period of laser pulse emission can be on the order of nanoseconds. The laser beam emitted by the light source 110 can be a narrow-bandwidth beam with a wavelength outside the visible light range. The light source 110 can be other types of light sources, which are configured to emit other forms of radiation, such as infrared beams.

[0059] As Figure 1AAs shown, the light beam 138a emitted by the light source 110 is transmitted through an area on the reflector 112. In some embodiments, the area for transmitting the light beam 138a is provided in the central area of the reflector 112 and includes two opposite surfaces, both of which are coated with an anti-reflection coating, such that the light beam 138a emitted by the light source 110 is transmitted through the central area. In some embodiments, one or more optical elements of the LiDAR system 100 may be coated with an anti-reflection coating. In some embodiments, the reflector 112 may further include a through hole for transmitting the light beam 138a in the central area. In some embodiments, when the LiDAR system 100 uses a coaxial optical path, the reflector 112 can be used to provide a transmit (or output) optical path (e.g., light beams 138b, 138c, or 138d) and a receive (or return) optical path (e.g., return light beams 142a, 142b, or 142c) before the collimating element 114, such that the transmit optical path and the receive optical path can share the same collimating element 114, and the optical path can be more compact to save the space that the LiDAR system 100 may occupy. In some embodiments, the light source 110 and the receiver 134 can use respective collimating elements, and the reflector 112 can be arranged on the optical path behind the collimating element associated with the receiver 134.

[0060] In some embodiments, the light beam 138a is emitted by a laser tube of the light source 110 and is collimated by the collimating element 114 into a nearly parallel light beam 138b to enter the scanning module 106. The collimating element 114 can also be used to collect at least a portion of the return light beam 142a reflected by an object 102 in the environment. The collimating element 114 may include a collimating lens or other suitable element capable of collimating light beams.

[0061] In some embodiments, the nearly parallel light beam 138b can pass through a rotating prism 116 driven by a driver 126 to form a dynamic scanning light beam 138c. For example, as Figure 1A shown, the first surface 116-1 of the prism 116 can be substantially parallel to the collimating element 114, and the nearly parallel light beam 138b can be incident on the first surface 116-1 and pass through the first surface 116-1. Then, when the prism 116 rotates about the axis 118, the nearly parallel light beam 138b can be redirected (e.g., due to refraction) by the second surface 116-2 of the prism 116 to form a dynamic scanning light beam 138c. The dynamic scanning light beam 138c can be redirected to the reflector 120.

[0062] In some embodiments, the dynamic scanning beam 138c incident on the reflector 120 and driven to rotate by the driver 128 can be reflected by rotating the reflector 120 that can rotate about the axis 122 to form a 360° scanning beam, which is set as the outgoing beam 138d. The outgoing beam 138d can be emitted by the LiDAR system 100 for scanning the environment. In some embodiments, the rotation of the prism 116 and the rotation of the reflector 120 can be driven by the drivers 128 and 126 respectively, and the drivers 128 and 126 are controlled by the controller 130.

[0063] In some embodiments, the outgoing beam 138d can be incident on (i.e., strike) an object 102 in the environment. At least a part of the outgoing beam 138d can be reflected by the object 102 and form a reflected beam as the return beam 142a, and the return beam 142a returns to the original optical path to be received by the LiDAR system 100. As Figure 1A shown, the return beam 142a can be incident on the reflector 120 and reflected by the reflector 120 into a return beam 142b that is transmitted to the second surface 116-2 of the prism 116. The return beam 142b can be redirected by the second surface 116-2 to the first surface 116-1. The beam 142b can be incident on the first surface 116-1 at a substantially perpendicular angle. The return beam 142b can pass through the first surface 116-1 of the prism 116 as the return beam 142c to be incident on the collimating element 114. The collimating element 114 can also redirect (e.g., by focusing) the return beam 142c to the reflector 112. For example, as Figure 1A shown, the return beam 142c can be received by a non-central region of the reflector 112. In some embodiments, the non-central region of the receiving surface of the reflector 112 (e.g., facing the collimating lens 114) can be coated with a highly reflective film. Thus, the return beam 142c can be reflected into a return beam 142d to be received by the receiver 134. In some embodiments, the laser reception time can be determined, for example, by detecting the rising edge time and / or the falling edge time of the electrical signal pulse converted from the return beam 142d. In this way, the TOF processor 132 can use the signal reception time information and the signal transmission time information to calculate the TOF, so as to determine the distance between the object 102 and the LiDAR system 100. It should be noted that the TOF processor 132 can be a possible method for determining the distance between the object 102 and the LiDAR system 100. Alternatively, the LiDAR system 100 can utilize other methods to measure the distance, such as modulating the amplitude of the laser emission pulse, modulating the phase of the laser pulse, and modulating the laser emission frequency (or wavelength). For this case, an appropriately programmed processor can be used to determine the distance based on the reflected light (e.g., the return beam 142d).

[0064] In some embodiments, the light source 110 of the LiDAR system 100 can be a single-line or multi-line light source, and the corresponding receiver 134 for receiving the return beam 142d has the same number of lines as the light source 110.

[0065] In some embodiments, the tilt angle of the rotating prism 116 relative to the collimating element 114, the wedge angle between the first surface 116-1 and the second surface 116-2 of the prism 116, and / or the tilt angle of the reflector 120 relative to the collimating element 114 can be determined respectively according to the range of the field of view (e.g., including the range of the pitch angle as described in reference Figure 1C subset (b)). For example, when the reflector 120 rotates around the axis 122 of the LiDAR system 100, such a range corresponds to a 3D view measured by the angle between the outgoing beam (e.g., the outgoing beam 138d) and the horizontal direction of the main body of the LiDAR system 100 (e.g., Figure 1C as shown in subset (b)). For example, when the pitch angle is in the range between -60° and 30°, the tilt angle of the reflector 120 and the wedge angle of the prism 116 can be determined.

[0066] In some other embodiments, when the pitch angle of the field of view is determined (e.g., the outgoing beam forms an angle of 5° with the horizontal direction as shown in Figure 1C subset (b)), the material and the wedge angle of the rotating prism 116 can be determined accordingly. In some embodiments, when the wedge angle of the prism 116 is relatively small, the refractive index of the prism 116 can be relatively high. In some other embodiments, when the wedge angle of the prism 116 is relatively large, the refractive index of the prism 116 can be relatively small. In some embodiments, a material with a relatively high refractive index can be used to minimize the wedge angle of the prism 116, thereby reducing the space occupied by the LiDAR system 100. For example, the prism 116 can be made of an optical material with a refractive index in the range of 1.7 - 2.1, such as any value of 1.7, 1.75, 1.8, 1.85, 1.9, 1.95, 2, and 2.1, and the wedge angle can be in the range of 10° - 25°, such as any angle of 10°, 11°, 12°, 13°, 14°, 15°, 16°, 17°, 18°, 19°, 20°, 21°, 22°, 23°, 24°, and 25°. For example, the prism 116 can be composed of the material H-ZF72A with a refractive index of 1.9229, and the wedge angle of the prism 116 can be 21°.

[0067] In some other embodiments, when the pitch angle (e.g., as Figure 1C shown) is -15°, the tilt angle of the reflector 120 relative to the vertical direction substantially perpendicular to the collimating element 114 is 52.5°.

[0068] In some embodiments, the number of lines of the light source 110 and the focal length of the collimating element 114 can be determined based on the angular accuracy of the point cloud pattern generated by the LiDAR system 100. For example, when the difference between adjacent angles of the point cloud pattern is less than 1.35°, the focal length of the collimating element 114 and the spacing between multiple lines of the light source 110 can be determined accordingly. When the light source 110 is a 6-line light source, the spacing between the lines of the light source 110 is 470 µm, and the focal length of the collimating element 114 can be determined to be approximately 20 mm. In another example, when the difference between adjacent angles of the point cloud pattern is even smaller, the spacing between multiple lines of the light source 110 can be further reduced, the focal length of the collimating element 114 can be increased, and / or the number of lines of the light source 110 can be increased.

[0069] Figure 1B FIG. shows an exemplary system 180 of a circuit of a LiDAR system 100 for Figure 1A according to an embodiment of the present disclosure. In some embodiments, as Figure 1B shown, the system 180 includes a transmission circuit 182 (e.g., connected to the light source 110), a receiving circuit 184 (e.g., connected to the receiver 134), a sampling circuit 186 (e.g., connected to the TOF processor 132), and a computing circuit 188 (e.g., connected to the TOF processor 132). The circuits 182-188 are connected to each other to operate the LiDAR system 100.

[0070] In some embodiments, the transmission circuit 182 is configured to control the light source 110 to transmit a sequence of light pulses (e.g., a sequence of laser pulses). The receiving circuit 184 is configured to control the receiver 134 to receive the sequence of light pulses reflected by the detected object 102. The receiving circuit 184 may also be configured to convert the sequence of light pulses to obtain an electrical signal. The electrical signal can be processed by the receiving circuit 184 and output to the sampling circuit 186. The sampling circuit 186 samples the electrical signal to obtain a sampling result. The computing circuit 188 is configured to determine the distance between the LiDAR system 100 and the detected object 102 based on the sampling result of the sampling circuit 186.

[0071] In some embodiments, the system 180 further includes a control circuit 190 configured to control the circuits 182-188. For example, the control circuit 190 can be configured to control the operating time of various circuits and / or to set parameters of the circuits, etc. It should be understood that Figure 1B the circuits shown in are embodiments for illustrative purposes and are not meant to be limiting. As described herein, Figure 1BThe number of one or more circuits shown may be more than one to emit at least two light beams in the same direction or different directions respectively. For example, the light-emitting chips in at least two transmission circuits for emitting at least two light beams may be encapsulated in the same module. In another example, each transmission circuit may include a laser-emitting chip, and the dies in the laser-emitting chips in the at least two transmission circuits are encapsulated together and accommodated in the same package space.

[0072] In some embodiments, in addition to Figure 1B the circuits shown in, system 180 may further include a scanning module (not shown) configured to control the propagation direction of at least one laser pulse sequence emitted by transmission circuit 182.

[0073] Figure 1C FIG. shows a schematic diagram of a scanning LiDAR system on a movable platform 101 according to some embodiments of the present disclosure, and the scanning LiDAR system represents any LiDAR system described herein. In some embodiments, the LiDAR system is placed on top of the movable platform 101 and scans the environment around the movable platform 101. In some embodiments, the scanning field of the LiDAR system on the movable platform 101 includes an azimuth angle in the range from 0° to 360° and a pitch angle θ in the range from -60° (60° below the horizontal direction of the LiDAR system) to 30° (30° above the horizontal direction) (shown in subset (b) of Figure 1C . For example, the LiDAR system may be placed on top of the movable platform 101 (such as an autonomous vehicle), about 1 meter to 2 meters from the ground, and designed to scan the environment at a pitch angle from -40° to 5°. The LiDAR system may be placed at any height suitable for an autonomous vehicle from the ground. It should be understood that Figure 1C the LiDAR system, the movable platform 101, and the scanning range provided in are examples for illustrative purposes and are not meant to be limiting. Given the various embodiments described herein, the LiDAR system may be mounted on any type of movable platform or movable object in any suitable arrangement (such as on the top, bottom, or side of the movable platform or movable object) to provide an appropriate scanning range in the environment and within the scope of the present disclosure. For example, the LiDAR system may be mounted at any position on an unmanned aerial vehicle (UAV), an autonomous vehicle, a remotely controlled vehicle, a handheld gimbal, and / or a wearable device to provide an appropriate scanning range for the corresponding environment.

[0074] In some embodiments, the distance and direction of the (one or more) objects in the environment detected by the LiDAR system can be used for remote sensing, obstacle avoidance, mapping, modeling, navigation, etc. In some embodiments, the LiDAR system described in various embodiments of the present disclosure can be applied to a movable platform 101 such as an unmanned aerial vehicle. For example, the LiDAR system can be installed on the platform body of the movable platform 101. The mobile platform 101 with the LiDAR system can measure the external environment, for example, measure the distance between the mobile platform 101 and an obstacle for obstacle avoidance and other purposes, such as performing two-dimensional (2D) or three-dimensional (3D) mapping of the external environment.

[0075] In some embodiments, the movable platform 101 can include any suitable movable object, device, mechanism, system, or machine configured to travel on or within a suitable medium such as a surface, air, water, track, space, underground, etc. For example, the movable platform 101 includes at least one of a UAV, a car, a remote control vehicle, a robot, and a camera. In some embodiments, when the LiDAR system is applied to a UAV, the platform body can be the fuselage of the UAV. In some embodiments, when the LiDAR system is applied to a car, the platform body can be the body of the car. For example, the car can be an autonomous vehicle or a semi-autonomous vehicle. The LiDAR system can be installed on the top of an autonomous vehicle as shown in subset (a) of the figure such as Figure 1C The LiDAR system can also be coupled, connected, installed, or otherwise appropriately mounted on the movable platform 101. The LiDAR system can also be a built-in module of the movable platform 101. In some embodiments, when the LiDAR system is applied to a remote control vehicle, the platform body can be the body of the remote control vehicle. In some embodiments, when the LiDAR system is applied to a robot, the platform body can be the robot. In some embodiments, when the LiDAR system is applied to a camera, the platform body can be the camera itself.

[0076] The types of systems discussed in the present disclosure can be equivalently applied to other types of movable platforms, movable objects, or any suitable object, device, mechanism, system, or machine configured to travel on or within a suitable medium such as a surface, air, water, track, space, underground, etc.

[0077] Referring again to Figure 1AIn some embodiments, TOF information can be processed and calculated by the LiDAR system on the movable platform 101 during movement. The LiDAR system can generate a 2D or 3D map of the external environment. In some embodiments, the light beam and electrical signal can be collected by the LiDAR system on the movable platform 101 and transmitted wirelessly or via a wired connection to another computing device or computing system for processing and calculating the distance and position of the object and generating a 2D or 3D map of the external environment.

[0078] Figure 1D The embodiment according to the present disclosure is shown Figure 1A FIG. 1 is an exemplary scanning pattern of the scanning LiDAR system 100. It will be appreciated that when the speed of the optical elements in the scanning module 106 changes, the scanning pattern may change accordingly.

[0079] Figure 1E and 1F The embodiment according to the present disclosure is shown Figure 1A 1 is an exemplary scanning pattern of the scanning LiDAR system 100. In some embodiments described herein, the prism 116 may include a plurality of rotating prisms. Each prism may be driven by a separate motor. In some embodiments, regardless of the reflector 120, when the prism 116 includes a single prism, the scanning pattern is as follows: Figure 1E In some embodiments, when the prism 116 includes a plurality of prisms, the scanning pattern may include a 2D pattern, such as Figure 1F 1 and 2. The scanning pattern of the prism 116 comprising two prisms.

[0080] In some embodiments, in order to make the LiDAR system more compact, the size of one or more devices (e.g., one or more optical elements) included therein can be reduced. On the other hand, due to certain requirements and restrictions on the optical path for the normal function of the LiDAR system, the size of some devices of the LiDAR system cannot be easily reduced. For example, Figure 1A As shown, the reflector 120 is sized and configured to accommodate optical elements (e.g. Figure 1A The reflector 120 and the prism 116 in the housing (for example, below Figure 2The size of the housing 223) therein cannot be freely reduced. Therefore, a LiDAR system with a more compact structure than the LiDAR system 100 is required. For example, as discussed herein, by adjusting the arrangement of one or more optical elements of the optical assembly in the LiDAR system, the light beam can be received and reflected by the reflecting surface at a position closer to the central region of the reflecting surface before being guided outwards to scan the environment. Therefore, the optical assembly of the LiDAR system can be more compact than the LiDAR system 100. It should be understood that two or more of the embodiments of the optical assembly described herein can be combined in any LiDAR system in any suitable arrangement and are within the scope of the present disclosure.

[0081] Figure 2 FIG. shows a schematic diagram of an exemplary scanning LiDAR system 200 according to an embodiment of the present disclosure. Elements of the LiDAR system 200 that are the same as those of the LiDAR system 100 are identified by the same reference numerals. In some embodiments, the LiDAR system 200 can be a single-station scanning LiDAR system. In some embodiments, the optical assembly 207 includes a first optical element having a wedge prism 216 (also referred to as a transmissive optical element or transmissive prism) that is rotatable about a first axis 217. The wedge prism 216 can be driven to rotate by a driver 128. In some embodiments, the wedge prism 216 can include a transparent material having a refractive index in the range of 1.7 to 2.1, such as any value of 1.7, 1.75, 1.8, 1.85, 1.9, 1.95, 2, and 2.1. The wedge prism 216 can have a wedge angle (i.e., the angle between the first surface 214 and the second surface 218) in the range of 16° to 25°, such as any angle of 16°, 17°, 18°, 19°, 20°, 21°, 22°, 23°, 24°, and 25°. For example, the wedge prism 216 can be made of a glass type H-ZF72A with a refractive index of 1.9229 and a wedge angle of 21°.

[0082] In some embodiments, the wedge prism 216 is configured to receive a near-parallel light beam 140b from the collimating element 114 at the first surface 214, and the near-parallel light beam 140b is collimated from the light beam 140a emitted by the light source 110. In some embodiments, the wedge prism 216 may be positioned substantially parallel to the collimating element 114 such that the near-parallel light beam 140b can enter the first surface 214 perpendicularly without refraction. In some other embodiments, the wedge prism 216 may not be parallel to the collimating element 114, and the near-parallel light beam 140b may be redirected, for example, refracted through the first surface 214 to the second surface 218. In some embodiments, the near-parallel light beam 140b may be incident on the second surface 218 and refracted by it, at which second surface, the light beam 140c exits the wedge prism 216 of the optical assembly 207. In some embodiments, the optical assembly 207 may include a plurality of rotating prisms, which includes the wedge prism 216. Each prism may be driven separately by a separate motor.

[0083] In some embodiments, the optical assembly 207 includes a second optical element 220 (also referred to as a reflective optical element) spaced apart from the wedge prism 216, which is positioned to receive the light beam 140c exiting the wedge prism 216. In some embodiments, as Figure 2 shown, the second optical element 220 may be implemented in the optical assembly 207 to replace Figure 1A the reflector 120 of the optical assembly 107 in Figure 2 . In some embodiments, the second optical element 220 may rotate about a second axis 222. In some embodiments, the second optical element 220 may be configured to redirect (e.g., reflect and / or refract) the light beam 140c (e.g., as an outgoing light beam received from the wedge prism) through the first surface 224 to the second surface 226 (also referred to as the reflective surface 226) of the second optical element 220. For example, as Figure 1A shown, compared with

[0084] , the light beam 140c may be incident on the first surface 224 and refracted by it into a light beam 140d for transmission to the central region of the reflective surface 226 of the second optical element 220. Figure 2As shown, the second optical element 220 can be driven by the driver 126 to rotate about the second axis 222 to scan the environment. In some embodiments, as Figure 2 shown, the first axis 217 can be aligned with the second axis 222. In some other embodiments, the first axis 217 can be inclined at a predetermined angle relative to the second axis 222, such as within a range of 5° to 10°, for example, any angle of 5°, 6°, 7°, 8°, 9°, and 10°. In another example, the first axis 217 can be parallel to the second axis 222.

[0085] In some embodiments, the second optical element 220 can include a triangular prism, such as a right-angle prism (as viewed from the front of the right-angle prism, as Figure 2 shown). In some examples, the second optical element 220 can include a transparent material having a refractive index greater than 1.7 to provide a high refractive index on the first surface 224 and the second surface 228. For example, the second optical element 220 can include a glass material having a refractive index of about 1.8467 (e.g., Chengdu Guangming H-ZF52). By providing the second optical element 220 (such as the prism as Figure 2 shown), after the outgoing beam 140f is refracted by the first surface 224 and reflected by the reflective surface 226, it can be refracted upward on the side wall of the prism (e.g., the second surface 228) and the housing 223 (e.g., compared with Figure 1A ). This may be because the beam 140d is received at the central region of the reflective surface 226, such that the beam 140e is received at a higher position on the surface 228. In this way, the optical assembly 207 and the corresponding LiDAR system 200 can be made smaller and more compact to cover a more desirable scanning range of the environment, so as to reduce the resistance from the air flow and lower the system noise during the rotation of the scanning module 206. The refraction angle of the outgoing beam 140f can be related to the thickness and material (e.g., refractive index) of the second optical element 220. In this way, the degree of beam deflection can be adjusted by selecting the angle between the first surface 224 and the reflective surface 226 and / or the material of the second optical element 220 as needed.

[0086] In some embodiments, in addition to or as an alternative to having a more compact system, a balancing element can be included in the LiDAR system for balancing the second optical element 220 during rotation. Figure 3A and 3BFIG. 0 shows a schematic diagram of an exemplary scanning LiDAR system 300 in accordance with an embodiment of the present disclosure. Elements of LiDAR system 200 that are the same as elements of LiDAR systems 100 and 200 are identified by the same reference numerals. LiDAR system 300 may be a single station scanning LiDAR system. In some embodiments, the optical assembly 307 includes a balancing element 310 attached to the second optical element 220, which is configured to balance the second optical element 220 during rotation about the second axis 222. As Figure 3B shown, the balancing element 310 may be attached to a motor 320 included in the actuator 128 that drives the second optical element 220 to rotate about the second axis 222 from the top of the balancing element 310. The balancing element 310 may further be attached to the second optical element 220 on a side surface. The balancing element 310 is configured to be positioned such that the combined center of gravity of the second optical element 220 and the balancing element 310 lies on the axis of rotation 222, thereby reducing the vibration of the motor 320 during rotation. In some embodiments, the balancing element 310 may include a metal piece attached to the second optical element 220, or a triangular prism with a reflective surface attached to the reflective surface 226 of the second optical element 220 as Figure 3A shown. Further details and various embodiments of the balancing element 310 will be described below with reference to Figures 20 - 24 which.

[0087] Figure 4FIG. 0 shows a schematic diagram of an exemplary scanning LiDAR system 400 in accordance with an embodiment of the present disclosure. Elements of the LiDAR system 400 that are the same as those of the LiDAR systems 100, 200, and 300 are identified by the same reference numerals. The LiDAR system 400 may be a single-station scanning LiDAR system. In some embodiments, to further translate the beam 140d towards the central region of the reflective surface 226 of the second optical element 220 to make the system more compact, the LiDAR system 400 further includes a third optical element 410 that is spaced apart from the first surface 214 of the wedge prism 216 and includes at least one surface that is inclined (or skewed) with respect to the first surface 214 of the wedge prism 216. For example, the third optical element 410 may be placed between the wedge prism 216 and the collimating element 114 to move the beam 140b exiting the collimating element 114 into the beam 140bb for entering the wedge prism 216. After being refracted by the surfaces 224 of the wedge prism 216 and the second optical element 220, respectively, the beam 140dd is moved closer to the central region of the reflective surface 226 of the second optical element 220. In some embodiments, when the beam 140b enters the third optical element 410, the beam 140b may be refracted by the surface 412 of the third optical element 410 and further refracted by the surface 414 of the third optical element 410 when exiting the third optical element 410 as the beam 140bb.

[0088] In some embodiments as shown in Figure 4 FIG. 5, the third optical element 410 may include one or more pairs of parallel surfaces. For example, the surface 412 may be parallel to the surface 414. Thus, the traveling direction of the beam 140bb may be parallel to the traveling direction of the beam 140b. In some embodiments, at least one surface, such as the surface 414 or the surface 412, may be inclined with respect to the surface 214 of the wedge prism 216. In some embodiments, the third optical element 410 may include a parallel glass plate. In some embodiments, the degree of refraction of the beam 140b and the corresponding moving distance of the beam 140b to the beam 140bb caused by the third optical element 410 may be related to the thickness of the third optical element 410, the material including the third optical element 410, and / or the angle at which the surface 412 or 414 of the third optical element 410 is inclined with respect to the wedge prism 216. For example, the thicker the parallel glass plate, or the higher the refractive index of the material used in the third optical element 410, the higher the degree to which the beam 140b may be refracted at the surface 412, and thus the more the beam (e.g., the beam 140dd) may be translated or moved towards the central region of the reflective surface 226. In some embodiments, the third optical element 410 may have a high refractive index, such as a refractive index higher than 1.8.

[0089] Figures 5A - 5DA schematic diagram showing various optical components for the exemplary scanning LiDAR systems disclosed herein according to embodiments of the present disclosure. In some embodiments, Figure 5A the optical component 510 of Figure 1A may correspond to the optical component 107 and the collimating element 114 of the LiDAR system 100 of Figure 2 or the optical component 207 and the collimating element 114 of the LiDAR system 200 of Figure 5B the optical component 520 of Figure 4 may correspond to the optical component 307, the third optical element 410, and the collimating element 114 of the LiDAR system 400 of

[0090] In some embodiments, as shown in the optical component 530 of Figure 5C the third optical element 410 and the wedge prism 216 in Figure 5B may be replaced by the optical element 550 to obtain a similar effect of moving the light beam 558 towards the central region of the reflective surface 226 of the second optical element 220. The optical element 550 may be a special-shaped or irregular prism. Compared with the optical component 520, fewer optical elements are included to construct the optical component 530. Therefore, the LiDAR system can be more compact and simpler. In addition, compared with the optical component 510, the light beam can be received at the central region of the reflective surface 226 in the optical component 530, which is also beneficial for a more compact LiDAR system.

[0091] In some embodiments, based on multiple factors, such as the refractive index of the material used in one or more optical elements of the LiDAR system, the size of one or more optical elements, and / or the arrangement between one or more optical elements, etc., the pitch angle (e.g., Figure 2 the pitch angle θ in Figure 1C ) related to the vertical range of the scanning field of view of the outgoing light beam (e.g., Figure 1CIn the tilt angle θ), the optical element 550 in the optical component 530 can be made of a transparent material with a refractive index in the range of 1.9 - 2.1 (e.g., any value among 1.9, 1.95, 2.0, 2.05, and 2.1). In various embodiments, the range of the pitch angle θ can be variable. For example, it can be in the range of -50° to 20°, or -20° to 50°, or any other suitable range. In some cases, when the range of the pitch angle is large, the optical element 550 has a relatively high refractive index (e.g., a value close to 2). For example, the optical element 550 can be composed of glass type H-ZLAF90 with a refractive index of 2.00. As Figure 5C shown, the optical element 500 can have four sides, including a pair of parallel sides. The shortest side can have a length ranging from 5 mm to 20 mm, such as any number among 5 mm, 7 mm, 10 mm, 12 mm, 15 mm, 18 mm, and 20 mm. For example, the side 551 of the optical element 500 can have a length of 10 mm.

[0092] Referring to Figure 5C , in some embodiments, the first surface 552 of the optical element 550 provided as an irregular prism can have a first tilt angle α in the range of 10° to 30°, such as any angle among 10°, 12°, 15°, 18°, 20°, 22°, 25°, 28°, and 30°, where the first surface 552 is closer to the collimating element 114, and the first tilt angle α is measured between the first surface 552 and the direction parallel to the collimating element 114. For example, the first tilt angle α can be 26°. In some embodiments, the second surface 554 can have a second tilt angle β in the range of 30° to 50°, such as any angle among 30°, 32°, 35°, 38°, 40°, 42°, 45°, 48°, and 50°, where the second surface 554 is away from the collimating element 114 (or closer to the first surface 224 of the second optical element 220), and the second tilt angle β is measured between the second surface 554 and the direction parallel to the collimating element 114. For example, the second tilt angle β can be 40°. In some embodiments, to make the optical component 530 more compact, the first tilt angle α is selected to be greater than 10°, and the difference between the second tilt angle β and the first tilt angle α is greater than 10° (correspondingly, the distance between the first surface 552 and the second surface 554 can be increased) to further bend the outgoing light beam towards the central region of the reflective surface 226. In some embodiments, Figure 5CThe optical component 530 can help refract the outgoing light beam (e.g., light beam 558) towards the central region of the reflective surface 226 of the optical element 220, making the optical component 530 more compact. For example, compared with using the wedge prism 216 (e.g., made of glass type H-ZF72A with a refractive index of 1.9229 and a wedge angle of 21°) Figure 5A of the optical component 510, Figure 5C the optical component 530 can reduce the width of the second optical element 220 by approximately 20% by using the optical element 550. By making the optical component smaller, the motor power consumption and noise can also be reduced.

[0093] In some embodiments, as Figure 5D shown, the optical element 560 of the optical component 540 can be used to obtain a similar effect of moving the light beam 570d towards the central region of the reflective surface 226 of the second optical element 220. In some embodiments, the optical element 560 can include a prism. In some embodiments, as Figure 5D shown, the optical element 560 includes a first surface 562 and a second surface 564 connected by a sidewall having an inner surface 566. In some embodiments, the light beam 570a collimated by the collimating element 114 can be refracted by the first surface 562 to form a light beam 570b to be transmitted to the inner surface 566 of the sidewall. In some embodiments, the light beam 570b can be reflected by the inner surface 566 of the sidewall to form a light beam 570c. In some embodiments, after being refracted by the surface 562, the angle of the light beam 570b incident on the surface 566 can allow the light beam 570b to be totally internally reflected by the surface 566. In some embodiments, the light beam 570c can be incident on the second surface 564 and refracted by it to form a light beam 570d when leaving the optical element 560 towards the first surface 224 of the second optical element 220, such that the light beam 570d can be further refracted by the first surface 224 towards the central region of the reflective surface 226 of the second optical element 220.

[0094] In some embodiments, the inner surface 566 of the sidewall of the optical element 560 may be coated with a highly reflective film. In some embodiments, the first surface 562 of the optical element 560 is closer to the collimating element 114 and may have an inclination angle γ measured between the first surface 562 of the optical element 560 and a direction parallel to the collimating element 114. The inclination angle γ can be adjusted to redirect the light beam 570a through the first surface 562 such that the refracted light beam 570b can be totally reflected at the inner surface 566 of the sidewall, for example such that the incident angle of the light beam 570b is greater than the total internal reflection (TIR) angle. In some embodiments, the refractive degree can be controlled by controlling the material of the optical element 560. In some embodiments, the second surface 564 may be substantially parallel to the collimating element 114. In some other embodiments, the second surface 564 may be inclined relative to the collimating element 114.

[0095] Figure 6A and 6B FIGS. and

[0095] respectively show schematic diagrams of exemplary scanning LiDAR systems 600 and 650 according to embodiments of the present disclosure. Elements of the LiDAR systems 600 and 650 that are the same as those of the LiDAR systems 100, 200, 300, and 400 are identified by the same reference numerals. The LiDAR systems 600 or 650 may be single-station scanning LiDAR systems. In some embodiments, the optical path in a LiDAR system using a coaxial path may be affected by various noises such as stray light. In some embodiments, the stray light may include light scattered and / or reflected by one or more optical elements and / or other components (e.g., Figure 2 the balancing element 310, the light source 110, the receiver 134, or the inner surface of the housing 223) of the LiDAR system that is emitted by the light source 110, and the stray light can be detected by the receiver 134 and has a negative impact on the analysis of the effective signal, thereby reducing the accuracy of the TOF calculation and the efficiency of the LiDAR system. For example, when a LiDAR system is applied to scan an environment closer to a movable object, the noise signal caused by the stray light may have a greater impact on the accuracy. Some embodiments described herein can reduce the interference of the stray light on the receiver 134 by deviating the stray light from the receiving range of the receiver 134. In addition, two or more embodiments described herein can be combined to reduce or eliminate the negative impact of the stray light on the LiDAR system, and these embodiments are within the scope of the present disclosure.

[0096] In some embodiments, in order to reduce the negative impact of the stray light in the LiDAR system 600, the housing 610 for accommodating the wedge prism 216, the second optical element 220, and the balancing element 310 can be made as Figure 6AThe conical shape shown. The housing 610 can be transparent or made of a material capable of transmitting light to the scanning environment. In some embodiments, a housing 660 having an arcuate shape can be used in a LiDAR system 650 as shown in Figure 6B to reduce noise from stray light. The housing 610 can be transparent or made of a material capable of transmitting light to the scanning environment. In some embodiments, the conical housing 610 or the arcuate housing 660 can deflect light incident on and reflected or scattered by the surface of the housing 610 or the housing 660 out of the receiving range of the receiver 134. In some embodiments, the degree of reduction of stray light can be related to the tilt of the conical housing 610 or the curvature of the curved surface of the housing 660.

[0097] In some embodiments, the housing 610 having a conical shape can have a taper in the range from 1.3 to 1.7, such as any value of 1.3, 1.4, 1.5, 1.6, and 1.7, where the taper is measured by the ratio of the difference in diameters of the top cross-sectional circle 612 and the bottom cross-sectional circle 614 to the height (H) of the cone. For example, when the taper of the conical housing 610 is approximately 1.5, noise from stray light can be effectively reduced.

[0098] Figure 6C A schematic diagram of an exemplary housing 670 for accommodating one or more optical elements (such as, for example, the wedge prism 216 and the second optical element 220 or any other suitable optical element described herein) of a scanning LiDAR system (such as any LiDAR system described herein) according to an embodiment of the present disclosure is shown. The housing 670 can be Figure 6A the housing 610, Figure 6B the housing 660, or the housing 1300 of FIG. 13A. The housing 670 can be made of a material having a uniform thickness. The housing 670 can also be made of multiple materials having different thicknesses.

[0099] Figure 6DA schematic diagram of an exemplary housing 680 for accommodating one or more optical elements of a scanning LiDAR system according to an embodiment of the present disclosure is shown. The housing 680 may be constructed of a material similar to the housings 610, 660, 670, or 1300. For example, the housing 680 may be constructed of a material having a low refractive index, such as less than 1.65. The housing 680 may be constructed of a transparent plastic material, transparent glass, transparent polymer, etc. The housing 680 may include a light emitting portion having a uniform wall thickness when viewed from a top view or a front view. The housing 680 may include a plurality of light emitting portions, each of which has a uniform or non-uniform wall thickness when viewed from a top view or a front view. In an exemplary embodiment, at least two light emitting portions may extend at an angle, and the junction of adjacent light emitting portions may be coated with ink or paint to avoid the risk of mismeasuring points when the light beam penetrates two different light emitting portions. When viewed from a top view, the light emitting portions of the housing 680 may form a closed or unclosed circumference. For example, as Figure 6D shown, the housing 680 is formed of three parts, including a first part 682 having a uniform wall thickness, a second part 684 having a uniform wall thickness, and a third part 686 having a non-uniform wall thickness. In other embodiments, the housing 680 may include a different number of parts, such as one, two, four, five, six parts, etc., where each part has a uniform or non-uniform wall thickness, respectively.

[0100] In some embodiments, the housing 680 includes a first part 682 having a uniform wall thickness. In some embodiments, the inner surface of the first part 682 may be an inclined surface or a curved surface. For example, the first part 682 may include a curved or inclined corner as Figure 6D shown. The inclination angle of the inclined surface or the curvature of the curved surface may be determined according to the angle of the light incident on the inner surface of the housing 680 on the first part 682, such as the light beam 688a that exits the optical assembly from, for example, the reflection surface 120 or the second surface 228 of the second optical element 220. In some embodiments, the inclination angle of the inclined surface or the curvature of the curved surface may be designed to prevent the light beam 688a from directly incident on the inner wall of the housing 680 to reduce or avoid stray light.

[0101] In some embodiments, the first portion 682 may have an uneven wall thickness. The light beam 688a may be incident on the first portion 682 and refracted by the first portion 682 of the housing 680 to form a light beam 688b that exits the LiDAR system. In some embodiments, the first portion 682 may have a uniform wall thickness, and the light beam 688b may be vertically and / or laterally displaced relative to the position where the light beam 688a would exit the optical component in the absence of the first portion 682 of the housing 680. In some embodiments, when one or more optical elements of the optical component rotate, the light beam 688b of the LiDAR system may scan the field of view at an azimuth angle from 0° to 360° and a pitch angle θ1 greater than 0° (e.g., the angle between the light beam 688b and the horizontal direction at 0°), such as from 0° to 5°. For example, the pitch angle θ1 may be configured to be higher than a target angle value, where the range of the target angle value may be between 0 degrees and several tens of degrees.

[0102] In some embodiments, the housing 680 includes a second portion 684 having a uniform wall thickness. The tilt angle σ of the second portion 684 (e.g., the half-cone angle of the tapered portion) is in the range of 3° to 10°. The tilt angle of the second portion 684 may also be selected to prevent the light beam 689a from directly incident on the inner wall of the housing 680 to reduce or avoid stray light.

[0103] In some embodiments, the second portion 684 may have an uneven wall thickness. The light beam 689a may be incident on the second portion 684 and refracted by the second portion 684 of the housing 680 to form a light beam 689b that exits the LiDAR system. In some embodiments, when one or more optical elements of the optical component rotate, the light beam 689b of the LiDAR system may scan the field at an azimuth angle from 0° to 360° and a pitch angle θ2 in the range from -20° to 0° (e.g., the angle between the light beam 689b and the horizontal direction at 0°). In some embodiments, the second portion 684 may have a uniform wall thickness, and the light beam 689a may be vertically and / or laterally displaced relative to the position where it would exit the optical component in the absence of the second portion 684 of the housing 680.

[0104] In some embodiments, the housing 680 further includes a third portion 686 having a thickness that increases towards the bottom of the housing 680. For example, as Figure 6DAs shown, the inner wall of the housing 680 can have a uniform inclination in both the second part 684 and the third part 686 (e.g., along a substantially straight line as indicated by the dashed arrow), while the inclination of the outer wall of the housing 680 can vary in different parts. For example, as indicated by the dashed arrow, the outer wall in the second part 684 can have a smaller inclination angle (relative to the horizontal direction) than the outer wall of the third part 686. Thus, the thickness of the third part 686 increases towards the bottom of the housing 680. For example, the light beam 690a can be incident on the third part 686 and refracted by the inner surface of the third part 686 of the housing 680 to form a light beam 690b. When the light beam 690b exits the LiDAR system, the light beam 690b is further refracted by the outer surface of the third part 686 to form a light beam 690c. In an exemplary embodiment, the third part 686 can have a uniform wall thickness, and the light beam 690c can be significantly displaced relative to the position where the light beam 690a exits the optical component in the absence of the transparent housing.

[0105] In some embodiments, when one or more optical elements of the optical component rotate, the light beam 690c of the LiDAR system can scan the field at an azimuth angle from 0° to 360° and a pitch angle θ3 below -20° (e.g., within the range of -60° to -20°) (e.g., the angle between the light beam 690c and the horizontal direction at 0°). Generally, the thicker the wall of the housing 680, the more it bends the light beam, thus refracting the light beam (e.g., the light beam 690c) towards a lower direction to provide a wider scannable field of view along the vertical direction (e.g., towards Figure 6D the lower range in). In some embodiments, the difference or ratio between the thickness of the third part 686 and the thickness of the second part 684 can be adjusted to obtain a desired field of view. For example, the thicker the third part 686 is compared to the second part 684, the wider the field of view that can be obtained (e.g., the range of the pitch angle θ3 can be larger).

[0106] Therefore, by selecting an appropriate inclination angle or surface curvature of the first part 682 and / or the second part 684 of the housing 680, stray light can be effectively reduced or avoided. In addition, by selecting a suitable thickness and the degree of thickness variation of the third part 686, the scannable field of view of the LiDAR system can be increased, e.g., along the vertical direction. For example, by using a design of the housing 680 having a thicker part in the third part 686, compared with Figure 6C the housing 670 in, the scannable field of view of the LiDAR system can be increased from the range of -20° to 5° to the range of -60° to 5°.

[0107] It should be understood that the first part 682, the second part 684, and the third part 686 are examples of the housing 680 that can be used to reduce stray light and / or widen the scan field of view of the LiDAR system, which is not meant to be limiting. Any number of parts similar to any one of the first part 682, the second part 684, and the third part 686 can be arranged in any suitable order, tilt angle, and / or thickness for the housing of the LiDAR system to provide the desired scan field of view.

[0108] Figure 7A FIG. shows a schematic diagram of an exemplary scanning LiDAR system 700 according to an embodiment of the present disclosure. Elements of the LiDAR system 700 that are the same as those of the LiDAR systems 100, 200, 300, 400, 600, and 650 are identified by the same reference numerals. The LiDAR system 700 can be a single-station scanning LiDAR system. In some embodiments, in order to further reduce the negative impact of stray light on the LiDAR system 700, the light-emitting surface (such as surface 726) of the second optical element 720 can be an inclined surface. In some Figure 7A embodiments as shown, the LiDAR system 700 can use Figure 6A the conical housing 610 as shown. In addition, the light-incident surface 722 and the reflective surface 724 of the second optical element 720 can be substantially similar to the first surface 224 and the reflective surface 226 of the second optical element 220 as described herein. In some embodiments, the second optical element 720 can include a material similar to that of the second optical element 220. In some embodiments, the light-emitting surface 726 and the light-incident surface 722 of the second optical element 720 can form an obtuse angle θ in the range from 91° to 120°. As Figure 7A shown, the obtuse angle θ can be used to direct light so that the size of the optical assembly can be reduced. The value (or possible range of values) of the angle θ can be determined based on multiple factors, such as the refractive index of the material of the second optical element 720, the refraction angle of the light beam refracted by the light-incident surface 722, etc. For example, when the second optical element 720 is composed of a material with a refractive index of 1.818, the obtuse angle can be approximately 100°.

[0109] In some embodiments, by making the light-emitting surface 726 an inclined surface, the space occupied by the optical assembly of the LiDAR system 700 can be reduced. Therefore, the inclined surface of the light-emitting surface 726 can be used to make the optical assembly more compact. The inclined surface of the light-emitting surface 726 can also reduce the negative impact of stray light. For example, the inclined light-emitting surface can be used in combination with other methods described in the present disclosure (such as the conical housing 610 or the arc-shaped housing 660) to reduce system noise from stray light while reducing system space.

[0110] Figure 7B FIG. shows a schematic diagram of the wedge prism 216 of a scanning LiDAR system according to an embodiment of the present disclosure. As described above, the wedge prism 216 may include a wedge angle between a first surface 214 and a second surface 218 in the range from 18° to 23°, such as any angle among 18°, 19°, 20°, 21°, 22°, and 23°. For example, the wedge prism 216 may have a wedge angle of approximately 21°. In some embodiments, the wedge prism 216 may be positioned such that the first surface 214 may be substantially parallel to the collimating element 114.

[0111] Figure 7C FIG. shows a schematic diagram of an exemplary optical element 760 (e.g., a transmission prism) as an alternative to the wedge prism 216 for various scanning LiDAR systems according to an embodiment of the present disclosure. In some embodiments, the optical element 760 may be a wedge prism having a wedge angle between a first surface 762 and a second surface 764 in the range from 16° to 25°. For example, the optical element 760 may have a wedge angle of approximately 21°.

[0112] In such Figure 2 and Figure 7B In some embodiments as shown, stray light may be detected by reflection of the light beam 144 received from the collimating element 114 by the first surface 214 of the wedge prism 216. To reduce stray light, at least one surface of the optical element 760 may be tilted, as Figure 7C shown. In some embodiments, the first surface 762 closer to the collimating element 114 may be tilted such that the stray light in a predetermined path may deviate from the receiving range of the receiver 134. For example, as Figure 7C shown, the first surface 762 may be tilted clockwise. In some embodiments, the first surface 762 of the optical element 760 may have an inclination angle φ measured between the first surface 762 and the direction parallel to the collimating element 114, and the inclination angle φ is in the range from 5° to 9°, such as any angle among 5°, 6°, 7°, 8°, and 9°. In some embodiments, the second surface 764 of the optical element 760 away from the collimating element 114 may have an inclination angle ψ measured between the second surface 764 and the direction parallel to Figure 7C the collimating element 114 as shown in, and the inclination angle ψ is in the range from 12° to 16°, such as any angle among 12°, 13°, 14°, 15°, and 16°. For example, as Figure 7CAs shown, the first tilt angle φ can be about 7°, and the second tilt angle ψ can be about 14°. Thus, stray light can be effectively reduced by using the optical element 760. It should be understood that the parameters of the optical element 760 as described herein are discussed for illustrative purposes and are not meant to be limiting. The optical element 760 can have any other suitable and optimized tilt angles and / or wedge angles to effectively reduce the stray light of the LiDAR system.

[0113] Figure 8 FIG. shows a schematic diagram of an exemplary scanning LiDAR system 800 in accordance with an embodiment of the present disclosure. Elements of the LiDAR system 800 that are the same as those of the LiDAR systems 100, 200, 300, 400, 600, 650, and 700 are identified by the same reference numerals. The LiDAR system 800 can be a single-station scanning LiDAR system. The LiDAR system 800 can include a first optical element 860, such as a wedge prism or a transmissive prism. In some embodiments, the first optical element 860 can be made of a material similar to that of the first optical element 116 or 216. The wedge prism of the first optical element 860 can have a wedge angle similar to that of the wedge prism of the first optical element 116 or 216. In some embodiments, the first optical element 860 can be tilted relative to the collimating element 114. Thus, the first surface 862 closer to the collimating element 114 is tilted so that stray light in a predetermined path can be deviated from the receiving range of the receiver 134. For example, the first optical element 860 can be tilted in the counterclockwise direction, as Figure 8 shown. The first optical element 860 can also be tilted in the clockwise direction to reduce stray light. The tilt angle ω measured between the first surface 862 of the optical element 860 and the direction parallel to the collimating element 114 can be in the range of 5° to 10°, such as any angle among 5°, 6°, 7°, 8°, 9°, and 10°. Thus, as Figure 8 shown, the first axis 217 about which the first optical element 860 rotates can be tilted relative to the second axis 222 of the second optical element 220 to reduce the reflected light received by the element 134. In some embodiments, the first optical element 860 can instead be tilted in the clockwise direction, as Figure 7C shown. It should be understood that Figure 8 the parameters discussed in

[0114] Figure 9A and 9BSchematic diagrams of ranging modules 910 and 920 for scanning LiDAR systems according to various embodiments of the present disclosure are shown respectively. In Figure 9A and 9B In some embodiments as shown, each of the ranging modules 910 and 920 includes a reflector 112, a collimating element 114, a light source 110, and a receiver 134 that are respectively in different positions. In some embodiments as shown in Figure 9A the ranging module 910 includes a reflector 112, and the reflector 112 includes a first region 912 for transmitting the light beam 138 generated by the light source 110. The first region 912 of the reflector 112 may be at its center. The light source 110 may be spaced apart from the reflector 112 and placed on a first side 907 of the reflector 112 opposite to a second side 909. Two surfaces of the first side 907 and the second side 909 of the central region may be coated with an anti-reflection coating for transmitting the light beam 138. The reflector 112 may further include a second region 914, which is located, for example, in the peripheral region and is coated with a highly reflective coating on the second side 909 for reflecting the return light beam 916 towards the receiver 134. The receiver 134 may be spaced apart from the reflector 112 and placed adjacent to the second side 909 of the optical element 112. In some embodiments, the collimating element 114 is located between the reflector 112 and the wedge prism 216 ( Figure 9A not shown in

[0115] In some embodiments, a part of the light beam 138 emitted by the light source 110 transmits through the central region of the reflector 112. In some embodiments, the laser diode of the light source 110 may have a large emission angle, for example, covering a wide range. In some embodiments, the emission angle of the light beam 138 may be controlled by the area and / or position of the anti-reflection coating coated on the central region of the reflector 112. In some embodiments of the ranging module 910, stray light caused by the light beam (e.g., the light beam 902 in Figure 9A ) reflected in the central region of the outgoing light beam 138 may significantly affect the performance of the LiDAR system.

[0116] In some embodiments, the positions of the light source 110 and the receiver 134 may be switched as shown in Figure 9B to reduce stray light. For example, the light source 110 may be placed adjacent to the second side 909 of the reflector 112, and the receiver 134 may be placed adjacent to the first side 907 of the reflector 112. In some embodiments, as shown in Figure 9BAs shown, the ranging module 920 includes a reflector 112, and the reflector 112 includes a first region 922 for reflecting the light beam 138 generated by the light source 110. The first region 922 of the reflector 112 may be in the central region. The surface of the first region 922 facing the light source 110 may be coated with a highly reflective coating for reflecting the light beam 138. The reflector 112 may further include a second region 924 located on the peripheral region, and two surfaces on the first side 907 and the second side 909 of the second region 924 may be coated with an anti-reflection coating for transmitting the return light beam 916 to be received by the receiver 134 located below the reflector 112. In some embodiments, the collimating element 114 may be located between the reflector 112 and the wedge prism 216 ( Figure 9B not shown in the figure).

[0117] As Figure 9B shown, in some embodiments, the beam shaper 930 may be located in front of the light source 110 to reduce the emission angle of the light beam 138 emitted from the laser diode of the light source 110, and the light beam 138 may be concentrated on the central region of the reflector 112. In some embodiments, the beam shaper 930 may be a single lens, a cylindrical lens, or a set of lenses designed according to the laser diode and the light beam 138 emitted therefrom.

[0118] In some embodiments, as Figure 9B shown, after switching the positions of the light source 110 and the receiver 134, the reflected light beam in the central region (e.g., Figure 9B the light beam 902 in the figure) may be blocked by the reflector 112, thereby reducing the stray light detected by the receiver 134.

[0119] Figure 9C And Figure 9D respectively show schematic diagrams of ranging modules 950 and 960 for various embodiments of a scanning LiDAR system according to embodiments of the present disclosure. In some embodiments, Figure 9C the ranging module 950 may be similar to Figure 9A the ranging module 910 shown in the figure, except that the ranging module 950 further includes a waveguide 952 located between the light source 110 and the collimating element 114 for guiding the light propagation of the light beam 138 emitted by the light source 110 to the collimating element 114 in the waveguide 952 to reduce the stray light detected by the receiver 134.

[0120] In some embodiments, Figure 9D the ranging module 960 may be similar to Figure 9BThe ranging module 920 shown, in addition to the ranging module 960, further includes a waveguide 962 located between the light source 110 and the collimating element 114 for guiding the propagation of the light of the light beam 138 emitted by the light source 110 into the collimating element 114 in the waveguide 962 to reduce the stray light detected by the receiver 134. Additionally, Figure 9D the ranging module 960 in Figure 9C may not include a reflector (e.g., the reflector 112 in Figure 9C ), because the side walls of the waveguide 962 can reflect the light beam 138 to the collimating element 114, thus making the structure of the ranging module 960 more compact. In some embodiments, the light source 110 and the receiver 134 may be arranged at the same level to make the optical assembly more compact. In such a system, one or more optical elements (e.g., tilted, including reflective and / or transmissive regions, and / or waveguides) may be arranged between the light source 110 and the collimating element 114 to guide the outgoing light beam emitted from the light source 110 to the collimating element 114 and guide the return light beam from the collimating element 114 to be received by the receiver 134. In an exemplary embodiment, due to the presence of the waveguide 962, light can be reflected multiple times in the waveguide 962, thereby allowing the overall size of the module 960 to be reduced and also allowing the light source 110 and the receiver 134 to be on the same plane.

[0121] As Figure 9C and 9D shown, by using the optical waveguides 952 or 962, the stray light generated by the reflection on the surface of the collimating element 114 can be effectively avoided. In some embodiments, the optical waveguide 952 is integrated with the collimating element 114 in the ranging module 950 to form a connected optical element. In some embodiments, the optical waveguide 962 is integrated with the collimating element 114 in the ranging module 960 to form a connected optical element. The effective field angle of the light beam received by the Figure 9C receiver 134 in Figure 9D can be slightly larger than the effective field angle in Figure 9D . It should be understood that the various embodiments described herein can be used alone or in combination in various LiDAR systems.

[0122] As Figures 9C - 9E shown, the waveguides 952, 962 and 972 are used to guide the light beam (e.g., the light beam 138 shown in Figures 9C - 9E ) from the light source 110 to the collimating element 114. In various embodiments, the waveguides 952 - 972 can be made of a light-transmitting material (e.g., glass, transparent plastic, light-transmitting crystal, etc.). In one embodiment, since the waveguides 952 - 972 have a reflective coating on the sides 971A - 971B, light can be reflected from the sides of the waveguides 952 - 972 (e.g., the sides 971A - 971B, as Figures 9C - 9EThe reflected light beam 138 (as shown). For example, the side surfaces 971A - 971B can be coated with a metallic material having a high reflectivity (e.g., 80%, 85%, 90%, 95%, 98%, 99% reflectivity, etc.). In an exemplary embodiment, the metallic material can be aluminum, silver, titanium, copper, etc. Alternatively, the light beam 138 can be reflected from the side surfaces 971A - 971B due to total internal reflection. In this case, the refractive index of the waveguides 952 - 972 can be significantly higher than the ambient refractive index. For example, if the ambient refractive index is about 1 (e.g., if the ambient is air), the refractive index of the waveguide 952, 962, or 972 can be 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, etc. In some cases, the refractive index of the waveguide 952, 962, or 972 can be higher than 2.0. To achieve total internal reflection, the side surfaces 971A - 971B can be polished to have a roughness size that is equal to or less than the wavelength of the light emitted by the light source 110. For example, if the light source 110 emits red light with a wavelength of 700 nanometers, the roughness size of the side surfaces 971A - 971B can be less than 700 nanometers. In various embodiments, the light beam from the light source 110 is emitted at an angle onto the side surfaces 971A - 971B to cause total internal reflection from these side surfaces. In some cases, to ensure reflection from the side surfaces 971A - 971B, these side surfaces can include a multi - layer dielectric coating. For example, such a coating can be selected to act as a Bragg reflector. In some cases, the waveguide 952, 962, or 972 can include a photonic crystal structure (e.g., holes adjacent to the side surfaces 971A - 971B), which can further improve the reflection of the light beam emitted by the light source 110 from the side surfaces 971A - 971B.

[0123] Some embodiments described herein can be used to reduce system aberrations. For example, since the housing (e.g., housing 223, 610, or 660) for the optical elements that house the scanning module includes a circular shape and has a certain wall thickness, the housing may cause aberrations in the corresponding LiDAR system. The material used to manufacture the housing can have certain hardness, stiffness, and optical properties. To reduce the aberrations caused by the housing, a material with a low refractive index and a thin outer wall design can be used. In some embodiments, the conical housing 610 can have a taper in the range of 1.3 to 1.7, such as any value among 1.3, 1.4, 1.5, 1.6, and 1.7. The housing 610 or the housing 660 can be made of a material with a thickness in the range of 0.8 mm to 1.2 mm. The housing 610 or the housing 660 can be made of a material with a low refractive index, for example, in the range of 1.4 to 1.7, such as any value among 1.4, 1.5, 1.6, and 1.7. For example, the housing 610 can have a taper of 1.5, and the material forming the housing 610 can have a thickness of about 1 mm and a refractive index of about 1.53. It should be understood that two or more embodiments described herein can be combined to reduce or eliminate the negative impact of aberrations on the LiDAR system and are within the scope of the present disclosure.

[0124] In addition to Figure 6A the conical housing 610, one or more surfaces of the second optical element 220 can be curved to compensate for aberrations, as described below with reference to FIGS. 10A - 10C, 11A - 11C, and 12A - 12C, for application in various LiDAR systems. In some embodiments, the second optical element 220 can be a prism, such as a triangular prism, a right - angled prism, or any other suitable prism as described herein (e.g., a prism with an irregular shape). In some embodiments, the surfaces 224, 226, or 228 for refracting or reflecting the light beam as described with reference to Figure 2 can be curved to compensate for aberrations.

[0125] FIGS. 10A - 10C show a schematic view of a housing 610 including a second optical element 220 attached to a balancing element 310 according to an embodiment of the present disclosure from a front view 1010 (FIG. 10A), a right - hand view 1020 (FIG. 10B), and a top view 1030 (FIG. 10C). In some embodiments, the second surface 228 of the second optical element 220 (which refracts the light beam 223 ( Figure 2 ) that exits the second optical element 220 and receives the return light beam 142 ( Figure 2 ) entering the second optical element 220) can be made into a curved surface. For example, as shown in FIG. 10C, the second surface 228 can be oriented towards the light beam 223 that exits the second optical element 220 ( Figure 2The leaving direction of ( ) bends outward. The curvature of the curved second surface 228 can be optimized to compensate for the aberration caused by the housing 610.

[0126] Figures 11A - 11C show schematic views of a housing 610 including a second optical element 220 attached to a balance element 310 according to an embodiment of the present disclosure from a front view 1110 (Figure 11A), a right view 1120 (Figure 11B), and a top view 1130 (Figure 11C). In some embodiments, the surface 224 of the second optical element 220 (which refracts the light beam 140c received from the wedge prism 216 ( Figure 2 ) to the central region of the reflective surface 226) can be a curved surface. For example, as shown in Figure 11B, the surface 224 can bend outward in a direction opposite to the direction of the light beam 219 entering the second optical element 220 ( Figure 2 ). The curvature of the curved surface 224 can be optimized to compensate for the aberration caused by the housing 610.

[0127] Figures 12A - 12C show schematic views of a housing 610 including a second optical element 220 attached to a balance element 310 according to an embodiment of the present disclosure from a front view 1210 (Figure 12A), a right view 1220 (Figure 12B), and a top view 1230 (Figure 12C). In some embodiments, the reflective surface 226 of the second optical element 220 (which reflects the light beam 221 received from the first surface 224 ( Figure 2 ) to the second surface 228) can be a curved surface. For example, as shown in Figure 12A, the reflective surface 226 can bend outward toward the balance element 310. The curvature of the curved reflective surface 226 can be optimized to compensate for the aberration caused by the housing 610.

[0128] In some embodiments, two or more of the surfaces 224, 226, and 228 can be optimized in shape, such as a curved surface, to compensate for aberration.

[0129] Figures 13A and 13B show schematic views of a polyhedral housing 1300 according to an embodiment of the present disclosure from a front view 1310 (Figure 13A) and a top view 1320 (Figure 13B). In some embodiments, in order to reduce or prevent astigmatism introduced by a circular housing (such as the housing 610 or 650), the housing 1300 can have a polyhedral shape, such as an octahedral shape, as shown in Figures 13A and 13B. In some embodiments, the outer housing 1300 can have other types of polyhedral shapes, such as a tetrahedron, a hexahedron, or other suitable structures. It should be understood that the various embodiments described herein can be used alone or in combination for the shape of the housing and / or the optical element 220.

[0130] Figure 14A , 14B, 15A, 15B, 16A, 16B, 17A, 17B, 18A, 18B, 19A, and 19B illustrate exemplary scan patterns generated by various LiDAR systems (e.g., LiDAR systems 100, 200, 300, 400, 600, 650, 700, and / or 800) described in embodiments of the present disclosure. In some embodiments, as described herein, when scanning an environment, a LiDAR system may include a first rotating optical element, such as a wedge prism 116, 216, 760, or 860, and a second rotating optical element including a reflective surface, such as a reflector 120, a second optical element 220, or a second optical element 720. Although Figure 14A , Figure 14B , Figure 15A , Figure 15B , Figure 16A , Figure 16B , Figure 17A , Figure 17B , Figure 18A , Figure 18B , Figure 19A and Figure 19B The scan patterns in may correspond to a field characterized by an azimuth angle from 0° to 360° and a zenith angle in the range from 60° to 120°. It should be understood that similar scan patterns may be obtained from various embodiments of the LiDAR systems described herein, and the scan patterns may be characterized by other parameters suitable for different ranges or scan fields (e.g., using azimuth-elevation angles (e.g., Figure 1C subset (b) of), etc.).

[0131] Figure 14A , 14B , 15A, 15B, 16A, and 16B are exemplary scan patterns obtained by a LiDAR system having a single-line laser diode. Assume that the rotational speed of the first rotating optical element is v1, the rotational speed of the second rotating optical element is v2, the number of light source lines is 1, and the focal length of the collimating element (e.g., collimating element 114) is 20 mm. The wedge angle of the wedge prism 216, 760, or 860 is 21°.

[0132] In some embodiments, Figure 14A and Figure 14BExemplary scan patterns 1400 and 1410 of a LiDAR system are shown respectively. The LiDAR system has a single-line laser diode with a light source emission frequency of 40 kHz, where a first optical element (e.g., wedge prism 216), as a reflector or a prism including a reflective surface, rotates at a higher speed than a second optical element 220, and the ratio of v1 / v2 is greater than 10. For example, the rotational speed v1 of the first rotating optical element is 24000 rpm, and the rotational speed v2 of the second rotating optical element is 603 rpm. The integration time of the point cloud in the scan pattern is 0.1 s. The first optical element and the second optical element can rotate in the same direction to generate Figure 14A the scan pattern 1400 shown in Figure 14B . The first optical element and the second optical element can rotate in opposite directions to generate

[0133] In some embodiments, Figure 15A and Figure 15B Exemplary scan patterns 1500 and 1510 of a LiDAR system are shown respectively. The LiDAR system has a single-line laser diode with a light source emission frequency of 40 kHz, where a first optical element (e.g., wedge prism 216) rotates at a lower speed than a second optical element 220 (e.g., as a reflector or a prism including a reflective surface), and the ratio of v2 / v1 is greater than 10. For example, the rotational speed v1 of the first rotating optical element is 600 rpm, and the rotational speed v2 of the second rotating optical element is 13250 rpm. The integration time of the point cloud in the scan pattern is 0.1 s. The first optical element and the second optical element can rotate in the same direction to generate Figure 15A the scan pattern 1500 shown in Figure 15B . The first optical element and the second optical element can rotate in opposite directions to generate

[0134] In some embodiments, Figure 16A and 16B Exemplary scan patterns 1600 and 1610 of a LiDAR system are shown respectively. The LiDAR system has a single-line laser diode with a light source emission frequency of 40 kHz, where a first optical element (e.g., wedge prism 216) and a second optical element 220 (e.g., as a reflector or a prism including a reflective surface) rotate at high speeds, e.g., v1 > 6000 rpm, v2 > 6000 rpm. For example, the rotational speed v1 of the first rotating optical element is 16250 rpm, and the rotational speed v2 of the second rotating optical element is 17569 rpm. The integration time of the point cloud in the scan pattern is 0.1 s. The first optical element and the second optical element can rotate in the same direction to generate Figure 16AThe scanning pattern 1600 shown in Figure 16B The scanning pattern 1610 shown in

[0135] Figure 17A , 17B , 18A, 18B, 19A, and 19B are exemplary scanning patterns obtained by a LiDAR system with a multi-line laser diode. In some embodiments, when the emission light source uses a multi-line laser diode, compared with the point cloud density of the scanning pattern of a single-line laser diode as shown in Figure 14A , Figure 14B , Figure 15A , Figure 15B , Figure 16A and Figure 16B shown, the point cloud density of the scanning pattern as shown in Figure 17A , Figure 17B , Figure 18A , Figure 18B , Figure 19A and Figure 19B shown can be effectively improved. Additionally, compared with the motor speed of a LiDAR system using a single-line laser diode, the motor speed of a LiDAR system using a multi-line laser diode can be lower to achieve a similar point cloud effect. Assume that the rotation speed of the first rotating optical element is v1 and the rotation speed of the second rotating optical element is v2, the number of light source lines is 6, the light source spacing is 470 μm, the focal length of the collimating element (e.g., collimating element 114) is 20 mm, and the wedge angle of the wedge prism 216, 760, or 860 of the first optical element is 21°.

[0136] In some embodiments, Figure 17A and Figure 17B respectively show the exemplary scanning patterns 1700 and 1710 of a LiDAR system, where the LiDAR system has a multi-line laser diode (e.g., six-line) with a light source emission frequency of 240 kHz, and the integration time of the point cloud is 0.1 s. The first optical element (e.g., wedge prism 216) rotates at a higher speed than the second optical element 220 (e.g., as a reflector or a prism including a reflective surface). For example, the rotation speed v1 of the first rotating optical element is 24000 rpm, and the rotation speed v2 of the second rotating optical element is 603 rpm. The first optical element and the second optical element can rotate in the same direction to generate Figure 17A The scanning pattern 1700 shown in Figure 17B The scanning pattern 1710 shown in

[0137] In some embodiments, Figure 18A and Figure 18BExemplary scan patterns 1800 and 1810 of a LiDAR system are shown respectively, where the LiDAR system has a multi-line laser diode (e.g., six lines) with a light source emission frequency of 240 kHz, and the integration time of the point cloud is 0.1 s. The first optical element (e.g., the wedge prism 216) rotates at a lower speed than the second optical element 220 (e.g., a prism acting as a reflector or including a reflective surface). For example, the rotational speed v1 of the first rotating optical element is 600 rpm, and the rotational speed v2 of the second rotating optical element is 13250 rpm. The first optical element and the second optical element can rotate in the same direction to generate Figure 18A the scan pattern 1800 shown in Figure 18B . The first optical element and the second optical element can rotate in opposite directions to generate

[0138] the scan pattern 1810 shown in Figure 19A and Figure 19B . In some embodiments, Figure 19A Exemplary scan patterns 1900 and 1910 of a LiDAR system are shown respectively, where the LiDAR system has a multi-line laser diode (e.g., six lines) with a light source emission frequency of 240 kHz, and the integration time of the point cloud is 0.1 s. Both the first optical element (e.g., the wedge prism 216) and the second optical element 220 (e.g., a prism acting as a reflector or including a reflective surface) can rotate at high speeds. For example, the rotational speed v1 of the first rotating optical element is 15250 rpm, and the rotational speed v2 of the second rotating optical element is 17569 rpm. The first optical element and the second optical element can rotate in the same direction to generate Figure 19B the scan pattern 1900 shown in

[0139] . The first optical element and the second optical element can rotate in opposite directions to generate

[0140] the scan pattern 1910 shown in Figure 15A 、 Figure 15B and Figure 16A . In some embodiments, the rotational speed and / or direction of the first optical element (e.g., the wedge prism 216) and the second optical element 220 (e.g., a prism acting as a reflector or including a reflective surface) can be determined according to different system structures and / or actual application scenarios. Figure 15A 、 Figure 15B and Figure 16A . In some embodiments, the LiDAR systems discussed herein can be used in various application scenarios. In some embodiments, if the LiDAR system is used for obstacle avoidance and a more compact size and low cost are preferred, then a LiDAR system using a single-line light source and parameters described with reference to Figure 15A 、 Figure 15B and Figure 16A can be applied to obtain the point cloud patterns shown in Figure 15A 、 Figure 15B and Figure 16A .

[0141] In some embodiments, if a LiDAR system is used to identify objects or obstacles in an environment and is for low-speed application scenarios, then a LiDAR system using the single-line light source and parameters described with reference Figure 15A 、 15B and 16A can be used to obtain the point cloud patterns shown in Figure 15A 、 15B and 16A. The integration time can be increased to increase the density of the point cloud, thereby providing better coverage of the scanned environment.

[0142] In some embodiments, if a LiDAR system requires high resolution and accuracy in identifying obstacles and is for medium-speed and high-speed application scenarios, then a LiDAR system using the multi-line light source and parameters described with reference Figures 18A - 18B and Figure 19A can be used to obtain the point cloud patterns as shown in Figure 18A and 18B as well as Figure 19A shown. In some embodiments, for various application scenarios within a single scan or multiple scans, the LiDAR system can automatically or manually change one or more operating parameters as described herein, or switch between different operating modes. It should be understood that the LiDAR system can also be configured to change one or more parameters, such as rotational speed, rotational direction, and / or use of single-line or multi-line laser diodes, to switch between multiple application scenarios.

[0143] Figures 20 - 23 FIG. shows schematic diagrams of various embodiments of a scanning module 2000 according to an embodiment of the present disclosure. The scanning module 2000 includes an optical element (e.g., the second optical element 220 described herein) and a balancing element (e.g., the balancing element 310 described herein). In some embodiments, the scanning module 2000 described as in Figures 20 - 23 can be used in a LiDAR system, such as LiDAR systems 100, 200, 300, 400, 600, 650, 700, 800, and / or any other suitable LiDAR system. It should be understood that Figures 20 - 23 the optical element discussed in can use the second optical element 220 described in various embodiments of the present disclosure, by way of example for illustrative purposes and not meant to be limiting. Any suitable optical element (e.g., the optical element 720 of Figure 7A ) or other optical elements can also be used in the scanning module as described herein.

[0144] In some embodiments, as one of the functional modules of a LiDAR system, the scanning module may include a driver (such as a motor) to drive an optical element (such as the second optical element 220 or another optical element including a reflective surface) to rotate about an axis (such as axis 222). During rotation, the optical element may reflect and / or refract a light beam into space for scanning the environment to identify one or more objects, and for ranging one or more objects in the space (such as measuring distance, mapping, etc.) to form a 2D or 3D point cloud image, e.g., such as Figure 14A , Figure 14B , Figure 15A , Figure 15B , Figure 16A , Figure 16B , Figure 17A , Figure 17B , Figure 18A , Figure 18B , Figure 19A or Figure 19B in the point cloud of the scanning pattern. In some embodiments, depending on the optical design, the rotational speed of the motor in the scanning module may range from a few hundred RPM (revolutions per minute) to tens of thousands of RPM.

[0145] In some embodiments, for a high-speed rotating motor, if the rotor and / or the object driven to rotate by the motor has an unbalanced mass, such as an unbalanced mass distribution, or is unbalanced during installation, such as if the center of mass deviates from the center of rotation, the rotor of the motor may vibrate, deform, and / or generate internal stress. Such an impact on the rotor may further cause the motor to vibrate and generate noise, thereby reducing the working efficiency and operating life of the motor. Therefore, it is desirable to improve the mass distribution and balance of the rotor during the manufacturing and assembly processes to improve the dynamic balance of the motor during rotation.

[0146] In some embodiments, the mass distribution and dynamic balance of the balance can be improved by adding weight or reducing weight for balancing. For example, adding weight for balancing is obtained by attaching an adhesive (such as glue) to a lighter area of the rotor than other areas to increase the weight. At the same time, reducing weight for balancing is achieved by removing material from the heavier areas of the rotor, e.g., via machining.

[0147] In some embodiments, the rotor of the scanning module of a LiDAR system can include both an optical element and the rotor of an electric motor. Accordingly, the mass of the optical element can be balanced in order to improve the dynamic balance of the rotor of the scanning module. In some embodiments, the balance of the mass of the optical element of the scanning module can be improved by adding weight to the optical element. For example, one or more pieces of balance adhesive material can be added to one or more regions (such as surfaces) of the optical element to compensate for regions of the optical element that are lighter than other regions. In some embodiments, the balance adhesive material can have a darker color or can be opaque. Accordingly, the balance adhesive material may block the optical path, reducing light transmission and thus negatively affecting the performance of the LiDAR system. Additionally, from the perspective of manufacturing and assembling the LiDAR system, it is desirable to have predictable locations for adding the balance adhesive material to the optical element without blocking the optical path or affecting system efficiency.

[0148] In some embodiments, the weight balancing structure and method for an optical element of a scanning module for a LiDAR system, described below with reference to Figures 20 - 23 can reduce or prevent the adhesive material from blocking the optical path of the optical element, thereby avoiding a reduction or loss of the light transmission region of the scanning module and maintaining high performance of the LiDAR system. In some embodiments, the location for adding the adhesive material to the rotor can be more predictable, thereby ensuring a consistent optical path and sufficient transmission region for the optical element to provide consistent performance for the LiDAR system. The predictable location(s) for adding the adhesive material(s) can also be beneficial for a streamlined manufacturing and assembly process.

[0149] Figure 20 A schematic view of a scanning module 2000 for a LiDAR system according to an embodiment of the present disclosure is shown from a front view. Figure 21 A schematic view of the scanning module 2000 according to an embodiment of the present disclosure is shown from a perspective view. In some embodiments, the scanning module 2000 includes a motor module 2010 and an optical module 2020 (or optical assembly 2020), as Figure 20 and Figure 21 shown. In some embodiments, the motor module 2010 is configured to drive the optical module 2020 to rotate about an axis for scanning an environment by the LiDAR system.

[0150] In as Figure 20 and Figure 21In some of the illustrated embodiments, the motor module 2010 includes a stator 2030 of the motor, which is fixedly connected to the LiDAR system structure. The motor module 2010 also includes a rotor 2040 configured to be rotatable about an axis. In some embodiments, when driven to rotate by the motor, the rotor 2040 is connected to the optical module 2020 and rotates together with the optical module 2020.

[0151] In some embodiments, the optical module 2020 includes an optical element that includes a refractive surface and / or a reflective surface for refracting and / or reflecting a light beam during rotation of the optical module 2020 to scan the environment. The optical element of the optical module 2020 may include the optical element 220, the optical element 720, or another suitable optical element. For example, the optical element 220 may be a wedge prism, a triangular prism, a right prism, or other optical element including a reflective surface as described herein.

[0152] In some embodiments, the optical module 2020 may further include a balance element 310 connected to the optical element 220. In some embodiments, the weight of the balance element 310 may be less than the weight of the optical element 220. The optical element 220 may refract the light beam through the surface 224 and reflect the light beam through the first side 2001 of the reflective surface 226 as described in the present disclosure.

[0153] In some embodiments, the balance element 310 includes a surface 312 to be attached to the surface of the optical element 220, such as the reflective surface 226, from the second side 2002 of the reflective surface 226. For example, the balance element 310 may be attached (e.g., glued) to the reflective surface 226 of the optical element 220 using an adhesive.

[0154] In some embodiments, one or more objects (e.g., balance glue) for adjusting the weight of the balance element 310 may be attached to the balance element 310 for balancing the weight between the optical element 220 and the balance element 310 and for balancing the optical module 2020 during rotation about the axis. In some embodiments, the weight adjustment object (e.g., balance glue) may be attached to one or more surfaces of the balance element 310, such as the surface 314, the surface 318, and / or the surface 319 (on the back of the balance element 310 and parallel to the surface 318). In some embodiments, the balance glue may include epoxy resin AB glue. The balance glue may have a high density and be black or red. The balance glue may be attached to one or more surfaces of the balance element 310 through a heat curing process. In some embodiments, the balance glue may adhere to the upper part 322 (e.g., about the top 1 / 5) and / or the lower part 324 (about the bottom 1 / 5) of the surface 314, as Figure 21 shown, to improve the dynamic balance of the scanning module 2000 during rotation. The balance glue may be applied in strips or dots.

[0155] In some embodiments, the balancing element 310 further includes a surface 316 that can be connected to the motor module 2010 and is configured to rotate the optical module 2020 about an axis. For example, the rotor 2040 of the motor module 2010 can be connected to the surface 316 of the balancing element 310, such as by gluing or other types of physical connection or embedding, as Figure 20 shown. In some embodiments, the surface 316 of the balancing element 310 that can be connected to the motor module 2010 can be different from the surface 312 for attaching to the optical element 220 or the surfaces 318, 314, or 319 to be coupled to the balancing glue.

[0156] In some embodiments, as Figure 20 shown, the balancing element 310 can include a wedge prism, a triangular prism, or a right prism. For example, the wedge prism 310 can be glued to the wedge prism 220 from the second side 2002 of the reflective surface 226 of the wedge prism 220. In some embodiments, the optical module 2020 can be formed into a cube, a rectangular cuboid, a frustum of a pyramid, a cylinder, a cone, a frustum of a cone, or any other suitable shape. In some embodiments, the optical element 220 of the optical module 2020 can refract or reflect a laser beam on its surface as described herein, and the balancing element 310 can balance the weight of the optical component 2020. In some embodiments, the balancing element 310 can be made of materials such as, for example, glass, metal, plastic, and / or polymer. The optical element 220 can be made of materials such as, for example, transparent glass, polymer materials, and / or resins. In some embodiments as Figure 21 shown, the surfaces 318, 314, and / or 319 can be curved surfaces to improve the accuracy of the connection between the balancing element 310 (e.g., via the surface 316) and the motor bearing and reduce rotational noise. In an exemplary embodiment, the optical element 220 can be different in size from the balancing element 310. In some cases, the optical element 220 can be formed of a different material from the balancing element 310. For example, the refractive index of the optical element 220 can be different from the refractive index of the balancing element 310. In some cases, the transparency characteristics of the optical element 220 can be different from the transparency characteristics of the balancing element 310. In addition, the surface characteristics (e.g., surface roughness) of the optical element 220 can be different from the surface characteristics of the balancing element 310. In some cases, the shape of the optical element 220 can be different from the shape of the balancing element 310 (e.g., the optical element 220 can be a triangular prism with all acute angles, while the balancing element 310 can have at least one angle that is a right angle or an obtuse angle). In some cases, the balancing element 310 and the optical element 220 can have any suitable size and shape and be made of any suitable material.

[0157] Figure 22 FIG. shows a schematic diagram of using a balancing element 310 to balance a scanning module 2000 of a LiDAR system according to an embodiment of the present disclosure. In some embodiments, as Figure 22 shown, the optical module 2020 may include an optical element 220 attached (e.g., glued) to the balancing element 310. In some embodiments, the optical element 220 and the balancing element 310 may each include a prism. A beam 140c (e.g., the beam 140c received from the previously described optical element 216) may enter via the surface 224 and be refracted by the surface 224 toward the reflective surface 226. The beam 140d may be reflected by the reflective surface 226 toward the second surface 228. The beam 140e may be refracted by the second surface 228 to exit the optical element 220, and the beam 140f may scan the environment when the optical element 220 is driven by the motor module 2010 to rotate about an axis.

[0158] In some embodiments, the tilt angle η of the reflective surface 226 (e.g., relative to the vertical direction, e.g., when the optical element 220 is a right-angle prism, the angle between the reflective surface 226 and the second surface 228) may be adjusted according to different fields of view that the LiDAR system can scan. When the tilt angle η is larger, more of the beam 140d that can be bent downward, where as Figure 22 shown, the value of the angle β of the outgoing beam 140d becomes larger, and the field of view that the LiDAR system can scan is bent downward to focus on a lower region of the environment. On the other hand, when the tilt angle η is smaller, the value of the angle β of the outgoing beam 140d is smaller (here, the angle β is positive when measured downward from the line 2210, and the angle β is negative when measured upward from the line 2210), and the field of view that the LiDAR system can scan is focused on a higher region. In some cases, the angle β may be negative (as measured from the line 2210 drawn perpendicular to the surface 228, the outgoing beam 140f may point upward). For example, when the tilt angle η is 45°, the angle β may be zero, and the outgoing beam 140d may point in the horizontal direction. In an exemplary embodiment, when the tilt angle of the reflective surface of the second optical element is larger, the field of view that can be scanned by the optical assembly may be reduced, and when the tilt angle is smaller, the field of view may be higher. The angle β may be the intermediate angle of the pitch angle. In an exemplary embodiment, for a tilt angle η of 45°, the angle β may be zero; for a tilt angle η of 50°, the angle β may be 10°; and for a tilt angle η of 40°, the angle β may be -10°. In an exemplary embodiment, the tilt angle η may determine the pitch angle and the angular range of the intermediate angle of the pitch angle.

[0159] In some embodiments, the balancing element 310 can be made of a material having a different density from that of the material used for the optical element 220. For example, the material for the balancing element 310 can have a smaller density than the material of the optical element 220. In one example, the balancing element 310 can be made of a material having a density of about 3.4 - 3.5 g / cm3, and the optical element 220 can be made of a material having a density of about 3.6 - 3.7 g / cm3. In some embodiments, without adjusting the weight of the balancing element 310, the optical module 2020 may be unbalanced due to the density difference. For example, the optical element 220 can be heavier than the balancing element 310. Thus, during the rotation of the scanning module 2000, the unbalanced optical module 2020 may cause vibration of the rotor 2040, thereby negatively affecting the performance of the LiDAR system. Therefore, to balance the optical module 2020, one or more weight adjustment objects (such as balancing glue) can be attached to one or more surfaces of the balancing element 310 for adjusting the weight of the balancing element 310 to balance the optical module 2020 during rotation about the axis. In some embodiments, the one or more surfaces for attaching the one or more weight adjustment objects can include surfaces 314, 318, and / or 319 as shown in Figure 20 and 22 . The balancing glue or other weight adjustment objects can be added to these surfaces for balancing the weight and maintaining dynamic balance during the rotation of the optical module 2020.

[0160] Figure 23 FIG. shows a schematic diagram of using the balancing element 310 to balance the scanning module 2000 of a LiDAR system according to an embodiment of the present disclosure. The optical module 2020 can include an optical element 220 attached (e.g., glued) to the balancing element 310. In some embodiments, the optical element 220 and the balancing element 310 can each include a prism. The light beam can travel in the same optical path in the second optical element 220 as described in reference Figure 22 .

[0161] In as Figure 23In some of the illustrated embodiments, the optical module 2020 and the motor module 2010 may be mounted non - coaxially. For example, the optical module 2020 may be mounted to the motor module 2010 such that the central axis 2050 (e.g., the geometric central axis or the center of gravity) of the optical module 2020 does not coincide with the rotational axis 2060 of the motor module 2010. For example, when mounted to the motor module 2010, the optical module 2020 may be shifted left or right from the central axis. In some embodiments, the respective materials of the optical element 220 and the balancing element 310 may have the same density. Thus, the geometric central axis may overlap with the center of gravity. In some embodiments, the respective materials of the optical element 220 and the balancing element 310 may have different densities. Thus, the geometric central axis may not overlap with the center of gravity.

[0162] The non - coaxial mounting scheme may result in an imbalance of the scanning module 2000. For example, as Figure 23 shown, the portion of the optical module 2020 to the left of the rotational axis 2060 may be heavier than the portion of the optical module 2020 to the right of the rotational axis 2060. During rotation of the scanning module 2000 about the axis 2060, the unbalanced optical module 2020 may cause vibrations of the rotor 2040, thereby negatively affecting the performance of the LiDAR system. Thus, it is desirable to adjust and balance the weight of the optical module 2020 to provide balanced rotation. In some embodiments, a weight - adjusting object (e.g., the balancing glue as described above) may be added to the balancing element 310. For example, one or more surfaces for attaching one or more weight - adjusting objects may include the surfaces 314, 318, and / or 319 as Figure 21 and 23 shown. The balancing glue or other weight - adjusting objects may be added to these surfaces to balance the weight during rotation of the optical module 2020 and maintain dynamic balance.

[0163] In some embodiments as Figures 20 - 23 described, the balancing glue or other weight - adjusting objects for balancing the weight of the scanning module 2020 may be added to one or more surfaces of the balancing element 310 different from the surface 312, e.g., on the opposite side of the reflective surface 226 of the optical element 220 for reflecting the light beam, so as to avoid blocking the optical path, wasting the light - transmission area in the optical element 220, and degrading the performance of the optical element 220.

[0164] In addition, the positions on the balancing element 310 for adding balancing glue or other objects for balancing the weight of the scanning module 2020 can be predictable, such as on one or more of the surfaces 314, 318, or 319 of the balancing element 310. Thus, the light transmission regions in the optical element 220 affect the performance of the LiDAR system. The predictable positions on the balancing element 310 for adding adjustable weights can optimize the processes for manufacturing and assembling the balancing scanning module 2020 and improve the operating efficiency of the balancing scanning module 2020 in the LiDAR system. It should be understood that the balancing glue is taken as an example of the balancing element 310, and is not meant to be restrictive. The balancing element 310 can include any other suitable weight balancing objects, which can be connected to one or more surfaces of the balancing element 310 as described herein, including but not limited to being attached to, hooked to, snapped into, suspended, connected to, or attached by magnetic attraction, etc.

[0165] Figure 24 A flowchart of an exemplary method 2400 for guiding a light beam to scan an environment to detect one or more objects in the environment according to an embodiment of the present disclosure is shown. In some embodiments, the method 2400 can be performed by various LiDAR systems, such as LiDAR systems 100, 200, 300, 400, 600, 650, 700, and / or 800, or various embodiments of optical assemblies including the same.

[0166] In step 2402, the method 2400 includes rotating a first optical element (e.g., optical element 116, 216, Figure 5B the combination of 216 and 410, 550, 560, 760, or 860) about a first axis (e.g., axis 118 or 217), and rotating a second optical element (e.g., optical element 120, 220, or 720) about a second axis (e.g., axis 122, 222, or 2060). In some embodiments, the first optical element is spaced apart from the second optical element. In some embodiments, the first optical element includes a wedge prism. In some embodiments, the second optical element includes a triangular prism. In some embodiments, the first axis can be aligned with the second axis.

[0167] In step 2404, the method 2400 further includes guiding a light beam (e.g., light beam 219) from the first optical element to a reflective surface (e.g., surface 226) of the second optical element.

[0168] In step 2408, the method 2400 further includes reflecting the light beam (e.g., light beam 140d reflected into light beam 140e) through the reflective surface (e.g., reflective surface 226) to transmit into the environment.

[0169] Figure 25AShows a first optical element and a second optical element having respective axes of rotation. More specifically, Figure 25A Shows a system 100 having an axis 122A of a first optical element 116 and a different axis 122B of a second optical element 120. In an exemplary embodiment, the axis 122A and the axis 122B may not be aligned. For example, the axis 122A may be at an angle positioned relative to the axis 122B, and this angle may be a function of time (i.e., ) or may be a constant. For example, when the angle is a function of time, the axis 122B moves relative to the axis 122A over time. As Figure 25A shown, the optical element 116 may rotate about the axis 122A at a rate R1, and the optical element 120 may rotate about the axis 122B at a rate R2. In some cases, R1 and R2 have the same value, and in other cases, R1 is different from R2 (e.g., smaller or larger). In some cases, either (or both) of R1 or R2 may be time-dependent. In some cases, the time rate of change of R1 or / and R2 may be related (or anti-related) to the time rate of change of Figure 26 Shows a three-dimensional view of the optical elements 116 and 120. As Figure 26 shown, the elements 116 and 120 may be positioned at any suitable angle relative to each other, and may be positioned at any suitable position relative to each other (e.g., the position may be characterized by a displacement vector from the center of element 116 to the center of element 120).

[0170] Figure 26 Shows a three-dimensional view of a first optical element and a second optical element having respective axes of rotation according to an embodiment of the present disclosure.

[0171] As ​ shown, the axis 122A may not be parallel to the normal vector N1 drawn to the corresponding surface 2610 of the element 116. Similarly, the axis 122B may not be parallel to the normal vector N2 drawn to the corresponding surface 2611 of the element 120. However, in some cases, the axis 122A or / and the axis 122B may be parallel to the respective normal vectors N1 and N2. Optionally, the axis 122A may be oriented in any suitable direction relative to the normal vector N1 or N2. Similarly, the axis 122B may be oriented in any suitable direction relative to the normal vector N1 or N2.

[0172] Returning to ​ , in some cases, the axis 122A and the axis 122B may be configured to point in the same direction (e.g., )。For example, when the optical element 116 is configured to receive a light beam at a first surface (e.g., interface 2511, as ​ shown), if the first axis (e.g., axis 122A) is not tilted relative to the second axis (e.g., axis 122B), and the surface of the first optical element (e.g., optical element 116) (e.g., interface 2511, as ​ shown) is parallel to the collimating element 114, the light beam can be reflected and received by the receiver 134. In various cases, the magnitude of γ(t) can be selected to ensure that the incident optical path deviates from the reflected optical path such that the reflected light beam may not be received by the receiver 134.

[0173] ​ shows the angle of incidence between the light beam and the normal of the surface of the first optical element according to an embodiment of the present disclosure. And ​ shows that the collimating element 114 guides the exemplary light beam 2521 toward the surface 2511 of the element 116. In some cases, the collimating element 114 can be positioned such that there is a non-zero angle of incidence when measured with respect to the normal direction 2523 of the surface 2511 . Depending on the angle of incidence , the positions and orientations of the optical element 116 and the reflecting element 120 are selected to allow the reflected light from an object (e.g., ​ the object 102 in) not to be received by the receiver 134, which will be further explained below.

[0174] ​ shows the orientation of the second optical element 120 relative to the direction of the first optical element 116. For example, as ​ shown, the second optical element 120 rotates about the axis 122B relative to the second optical element 120 as ​ shown. For example, when the optical element 120 rotates to the position as ​ shown, the vector P1A drawn in the plane of the surface of the optical element 120 rotates to point in the direction of the vector P1B. ​ shows an example of the rotation characterized by the angle q measured between the vector P1A and the corresponding rotated vector P1B. The angle q is referred to herein as the phase angle between the rotation of the first optical element 116 and the second optical element 120.

[0175] In an exemplary embodiment, when the optical element 116 and the element 120 rotate in the same direction and when their respective rotation speeds are the same (e.g., when the relative speed of R1 and R2 is not a function of time), the scanned point cloud can be controlled by the angle of the axis 122A or the axis 122B, the angle between the axis 122A and the axis 122B and as described above with respect to​ the phase angle q described above is inclined in different directions. In some cases, when the optical elements 116 and 120 rotate in the same direction (for example, when the optical elements 116 and 120 rotate in the same direction at the same speed or different speeds), by controlling the relative phase (for example, ​ the vector q in ), the scanning pattern can be controlled. In some embodiments, the relative phase between the optical elements 116 and 120 can be adjusted by controlling, for example, the rotation speed R1 or R2. For example, when the rotation speeds R1 and R2 are the same, and after a period of time, one of the rotation speeds of R1 (or R2) increases (or decreases), the scanning pattern changes. In some cases, the rotation speed R1 (or / and R2) can first increase and then decrease (or first decrease and then increase), resulting in a change in the scanning pattern after (and during) the change in the rotation speed R1 (or / and R2).

[0176] In addition, the scanned point cloud can also be controlled by the positions and orientations of the optical elements 116 and 120. ​ Parameters that can be used to control the optical elements and the light source according to an embodiment of the present disclosure are shown. For example, ​ the optical elements 116, 120, and 114 are shown, which can be positioned and aligned (i.e., oriented) to allow the reflected light beam 2820 to be received by the receiver 134. In an example embodiment, the tilt angle ​ as shown can be adjusted to allow the light beam 2820 to be received by the receiver 134. Additionally or alternatively, the tilt angle of the light source 110 can also be adjusted to allow the reflected light beam 2820 to be received by the receiver 134. Furthermore, the positions and alignments of the optical elements 116, 120, and 114 and the direction of the light source 110 can be selected to reduce the exposure of the receiver 134 to stray light. For example, the stray light can be any light inside the system 100 (for example, light reflected from various surfaces (such as surface 2811), as indicated by the dashed line 2723). In various embodiments, the exposure of the receiver 134 to stray light can be minimized to allow accurate resolution of the object 102. In addition to controlling the angles and and , the shape of the optical element 116 can also be controlled. For example, as ​ shown, the surface 2810 can be configured to allow better "collection" of light (i.e., to allow the reflected light beam from the object 102 to reach the receiver 134). In some cases, the surface 2810 (or surface 2811) can be curved. Additionally or alternatively, the wedge angle of the element 116 can also be selected to allow optimal collection of light. In some cases, the reflector 120 can include a curved surface 2813.

[0177] Figures 29A - 29D It shows that the angle can be controlled by and To achieve different scanning patterns, such as Figure 28 In an example embodiment, element 116 and element 120 may rotate at the same angular velocity, and an example scanning pattern may be a single line pattern. For example, Figure 29A A scan pattern 2911A is shown over an example scanning LiDAR system 2913 positioned on a platform 2915 . Figure 29B Scan pattern 2911B is shown directed downward and sideways from system 2913. Figure 29C A scan pattern 2911C is shown directed laterally from system 2913, and Figure 29D Scan pattern 2911D is shown, which may be a combination of patterns 2911A-2911C.

[0178] Figure 30A -30C shows the tilt angle How the scan pattern can be controlled. For example, Figure 30A Shown with an angle The scanning pattern 2911A is as follows: Figure 30A As shown. When the scanning pattern 2911A (tilt angle The range may depend on other angles as described above , and may depend on various other parameters, such as the shape of elements 116 and 120, the distance between optical elements 114, 116, and 120, the presence of waveguides, etc.). In an exemplary embodiment, when the angle When the angle is within the range of 20 to 30 degrees, can be about 60 degrees (in some cases, the angle can vary within the range of ±20 degrees). FIG. 30B shows a In the exemplary embodiment, to obtain such a scanning profile (i.e., scanning pattern 2911B), the angle It can be in the range of 30 to 40 degrees. FIG. 30C shows an example of a In the exemplary embodiment, when the angle When within the range of 40 to 50 degrees, a scanning pattern 2911C can be obtained.

[0179] Figure 31 The variable angle as a function of the rotation angle of the optical element 116 and the reflective element 120 is shown. The curve graph. For example, when the optical element 116 rotates at an angular rate R1 (also known as the rotational speed), and the reflecting element 120 rotates at the same angular rate R1, the angle σ~100°. At a rotational angle of 150 degrees, the reflecting element 120 can be rapidly accelerated (e.g., accelerated within a range of dozens of rotational angles), and then decelerated back to the rotational speed R1, resulting in an acquired phase shift between the optical element 116 and the reflecting element 120. Such a phase shift may cause an angle change, as Figure 31 shown. For example, due to the phase shift, the angle can change from about 100 degrees to about 80 degrees. In an exemplary embodiment, the acquired phase shift can also be eliminated by decelerating the reflecting element 120 and then accelerating it back to the rotational speed R1. As shown, for example, between the rotational angles of 350 degrees and 360 degrees, σ changes from 80 degrees to 100 degrees.

[0180] In addition to controlling the tilt angle , the source angle ( Figure 28 ), and the rotational rates R1 and R2, the orientations of the axes 122A and 122B can also affect the scan patterns 2911A - 2911D. In an exemplary embodiment, the axis 122A can be aligned with the axis 122B, and in other cases, the axes 122A and 122B can be angled with each other. This alignment (misalignment) of these axes can be combined with any other parameter being controlled, and any other parameter is used to control the scan patterns 2911A - 2911D. For example, the axes 122A and 122B can be aligned, while the optical element 114 may not be parallel to the optical element 116 (i.e., the angle can be different from the angle , that is, the surface 2810 of the optical element 116 may not be parallel to the collimating element 114). In an exemplary embodiment, the tilt angle of the optical element 116 relative to the collimating element 114 can be defined as - (the angle drawn between the normal direction of the collimating element 114 and the normal direction of the surface 2810), where the angles and can be positive or negative. For example, in Figure 28 , the angle has a positive value and the angle has a negative value. Similarly, the tilt angle of the reflecting element 120 can be defined relative to the collimating element 114. In an exemplary embodiment, such a relative tilt angle can be given as - , which is related to the angle between the normal direction of the element 114 and the normal direction of the element 120 (this angle is through 90 - - (given). It should be understood that any other combination of the orientations of the optical elements 114, 116, and 120 can be combined with the specific orientations of the axes 122A and 122B and the specific rotational speeds R1(t) and R2(t) (e.g., such speeds can be a function of time) to achieve improved collection of light from the object 102. In an example embodiment, the rotational speed and can be used to indicate the time-dependent orientations of the axes 122A and 122B and the time-dependent rotational speeds R1 and R2, and such time-dependent rotational speeds can be combined with any suitable orientations of the optical elements 114, 116, and 120, which can also be time-dependent. For example, the tilt angle and the angle can be all (or at least some) time-dependent.

[0181] In some embodiments, the second optical element includes a prism, and the method 2400 further includes refracting a light beam through a first surface (e.g., surface 224) of the second optical element to a central region of the reflective surface 226 of the second optical element (e.g., refracting the light beam 140c into the light beam 140d), reflecting the light beam through the reflective surface 226 to the second surface (e.g., surface 228) (e.g., reflecting the light beam 140d into the light beam 140e), and refracting the light beam (e.g., the light beam 140e into the light beam 140f) through the second surface into the environment when the prism rotates about the second axis.

[0182] In some embodiments, the first optical element and the second optical element can rotate in the same direction to direct the light beam to scan the environment. In some embodiments, the first optical element and the second optical element can rotate in opposite directions to direct the light beam to scan the environment. In some embodiments, the first optical element and the second optical element can rotate at the same speed to direct the light beam to scan the environment. In some embodiments, the first optical element and the second optical element can rotate at different speeds to direct the light beam to scan the environment.

[0183] In some embodiments, the first optical element and the second optical element can be included in a single-station scanning LiDAR system. In some embodiments as Figure 1C described, the optical assembly including the first optical element and the second optical element can be located on a movable platform or a movable object (e.g., the movable platform 101).

[0184] In some embodiments as Figure 1CIn some of the illustrated embodiments, the mobile platform 101 includes a propulsion system (e.g., propulsion system 171) configured to propel the mobile platform 101 to move in the environment. The propulsion system may include one or more engines, motors, wheels, axles, magnets, rotors, propellers, blades, nozzles, or any suitable combination thereof.

[0185] In some embodiments, the mobile platform 101 includes a LiDAR system that includes an optical component located on the mobile platform 101. The LiDAR system can be any of a variety of LiDAR systems, such as LiDAR systems 100, 200, 300, 400, 600, 650, 700, and / or 800, or various embodiments of the optical components included therein. In some embodiments, the optical component of the LiDAR system is configured to direct a light beam to scan the environment to detect one or more objects in the environment. The optical component may include a first optical element (e.g., optical elements 116, 216, Figure 5B a combination of 216 and 410, 550, 560, 760, or 860), which is rotatable about a first axis (e.g., axis 118 or 217) and is configured to receive a light beam at a first surface (e.g., surface 116-1, 214, 552, 562, 762, or 862) of the first optical element and refract the light beam through a second surface (e.g., surface 116-2, 218, 554, 564, 764, or 866) of the first optical element, where the light beam exits the first optical element. The optical component may further include a second optical element (e.g., optical elements 120, 220, or 720) spaced apart from the first optical element and rotatable about a second axis (e.g., axis 122, 222, or 2060). The second optical element may be positioned to reflect the light beam to the environment through a reflective surface (e.g., surface 120, 226, or 724) of the second optical element to detect one or more objects.

[0186] One or more objects can be detected for remote sensing, obstacle avoidance, mapping, modeling, navigation, or any other suitable purpose. The data collected by the LiDAR system can be processed, and instructions can be generated accordingly for the corresponding purpose. The instructions can be generated by a processor located on the mobile platform 101. The instructions can also be generated by a computing device (e.g., a mobile device, a remote controller, a server system, etc.) remote from the mobile platform 101 and communicating with the mobile platform 101. The instructions can be sent to the mobile platform 101 via various suitable network communication methods. In some embodiments, the mobile platform 101 includes a controller (e.g., Figure 1C controller 173 in), which is configured to control the propulsion system 171 to propel the mobile platform 101 according to instructions generated based on the detected one or more objects.

[0187] The phrase "one embodiment", "some embodiments", or "other embodiments" in the specification means that a particular feature, structure, or characteristic related to the embodiment is included in at least one embodiment of the present disclosure. Thus, they do not necessarily mean the same embodiment. Additionally, these particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

[0188] In various embodiments of the present disclosure, the sequence number of a process has nothing to do with the order of the execution sequence. Instead, the order of the execution process should be determined by the function and the inherent logic. The sequence number should not limit the implementation of the embodiments of the present disclosure.

[0189] In various embodiments of the present disclosure, the phrase "B corresponding to A" may mean that B is associated with A and / or B may be determined based on A. However, determining B from A does not mean that B is determined solely based on A, but rather B may be determined based on A and / or other information. The term "and / or" herein merely describes the association relationship of related objects, indicating three relationships. For example, A and / or B may represent the presence of only A, the presence of only B, and the coexistence of both A and B. Additionally, the character " / " in the specification generally represents an "or" relationship between related objects.

[0190] Those skilled in the art can clearly understand that for the sake of convenience and brevity, the detailed structures, devices, components, systems, elements, features, or operation processes of the systems, devices, and subsystems may respectively refer to the corresponding structures, devices, components, systems, elements, features, or processes previously described in the embodiments, and may not be repeated.

[0191] In the embodiments of the present disclosure, the disclosed systems, devices, and methods may be implemented in other ways. For example, the above device embodiments are merely illustrative. Some features may be omitted or not executed. Additionally, the mutual coupling, direct coupling, or communication connection shown or discussed may be implemented by certain interfaces. The indirect coupling or communication connection of devices or subsystems may be electrical, mechanical, or other forms.

[0192] It should be understood that the disclosed embodiments are not necessarily limited in their application to the details of the construction and arrangement of the components set forth in the above description and / or shown in the drawings and / or examples. The disclosed embodiments can have variations or can be practiced or carried out in various ways. For example, one or more additional elements, devices, or systems not shown in the figures can be further provided between any of the elements, devices, or systems as described herein, and still enable the LiDAR system to operate in a substantially similar manner. It will be apparent to those skilled in the art that various modifications and variations can be made to the disclosed apparatus and systems. Considering the description and practice of the disclosed apparatus and systems, other embodiments will be apparent to those skilled in the art. This specification and the embodiments are only to be considered as exemplary, and the true scope is defined by the appended claims and their equivalents.

Claims

1. An optical component for guiding a light beam to scan an environment to detect one or more objects in the environment, the optical component comprises: a first optical element that is rotatable about a first axis and is configured to receive a light beam at a first surface of the first optical element, refract the light beam through a second surface of the first optical element, and the light beam exits the first optical element at the second surface; and a second optical element that is spaced apart from the first optical element and is rotatable about a second axis, and the second optical element is positioned to reflect the light beam through a reflective surface of the second optical element into the environment to detect the one or more objects; wherein the first optical element includes an irregular prism configured to translate the light beam toward a central region of the reflective surface of the second optical element.

2. The optical component according to claim 1, wherein controlling the orientation of the first optical element is for controlling a scanning pattern of the environment using the light beam.

3. The optical component according to claim 1, wherein controlling the orientation of the second optical element is for controlling a scanning pattern of the environment using the light beam.

4. The optical component according to claim 1, wherein controlling a first rotation speed about the first axis of the first optical element is for controlling a scanning pattern of the environment using the light beam.

5. The optical component according to claim 1, wherein controlling a second rotation speed about the second axis of the second optical element is for controlling a scanning pattern of the environment using the light beam.

6. The optical component according to claim 1, wherein further comprises: a light source for emitting the light beam; a collimating element for directing the light beam toward the first surface of the first optical element, wherein the collimating element is located between the light source and the first optical element, and controlling an inclination angle of the first optical element relative to the collimating element to control a scanning pattern of the environment using the light beam.

7. The optical component according to claim 6, wherein controlling an inclination angle of the second optical element relative to the collimating element to control a scanning pattern of the environment using the light beam.

8. The optical component according to claim 6, wherein controlling an inclination angle of the second optical element relative to the collimating element to control an amount of stray light received by a receiver of the light beam.

9. The optical component according to claim 1, wherein the second optical element further includes a first surface configured to refract the light beam to the reflective surface of the second optical element.

10. The optical component according to claim 1, wherein the light beam is refracted by the first surface of the second optical element to a central region of the reflective surface of the second optical element.

11. The optical component according to claim 10, wherein The second optical element further includes a second surface configured to refract the light beam reflected by the reflective surface into the environment, and the light beam exits the second optical element from the second surface.

12. The optical assembly according to claim 11, wherein at least one of the first surface, the reflective surface, or the second surface of the second optical element is a curved surface.

13. The optical assembly according to claim 11, wherein the second optical element includes a triangular prism.

14. The optical assembly according to claim 13, wherein the triangular prism is a right prism.

15. The optical assembly according to claim 11, wherein the second surface of the second optical element is substantially perpendicular to the first surface of the second optical element.

16. The optical assembly according to claim 11, wherein the second surface of the second optical element forms an obtuse angle with respect to the first surface of the second optical element, and the obtuse angle ranges from 91° to 120°.

17. The optical assembly according to claim 1, wherein the second optical element includes a transparent material having a refractive index greater than 1.

7.

18. The optical assembly according to claim 1, wherein the first optical element includes a wedge prism.

19. The optical assembly according to claim 18, wherein the wedge prism has a wedge angle in the range of 16° to 25°.

20. The optical assembly according to claim 18, wherein the wedge prism includes a transparent material having a refractive index in the range of 1.7 to 2.

1.

21. The optical assembly according to claim 18, wherein the first surface of the wedge prism is substantially parallel to the collimating element to collimate the light beam for reception by the first optical element.

22. The optical assembly according to claim 18, wherein at least one of the first surface and the second surface of the wedge prism is inclined with respect to the collimating element to collimate the light beam for reception by the first optical element.

23. The optical assembly according to claim 22, wherein the first surface of the wedge prism has a first inclination angle in the range from 5° to 9°.

24. The optical assembly according to claim 22, wherein the second surface of the wedge prism has a second inclination angle in the range from 12° to 16°.

25. The optical assembly according to claim 18, wherein the first optical element is positioned to be inclined with respect to the collimating element to collimate the light beam for reception by the first optical element.

26. The optical assembly according to claim 25, wherein the inclination angle of the first optical element with respect to the collimating element is in the range of 5° to 10°.

27. The optical assembly according to claim 1, further comprising a third optical element spaced apart from the first optical element and positioned to move the light beam toward a central region of the reflective surface of the second optical element.

28. The optical assembly according to claim 27, wherein The third optical element includes a parallel glass plate.

29. The optical assembly according to claim 27, wherein, the third optical element includes at least one surface that is inclined with respect to the first surface of the first optical element.

30. The optical assembly according to claim 1, wherein, the irregular prism includes a transparent material with a refractive index in the range of 1.9 - 2.

1.

31. The optical assembly according to claim 1, wherein, the length of one side of the irregular prism is in the range of 6 mm to 12 mm.

32. The optical assembly according to claim 1, wherein, the first surface of the irregular prism has a first inclination angle in the range from 15° to 35°.

33. The optical assembly according to claim 1, wherein, the second surface of the irregular prism has a second inclination angle in the range from 30° to 50°.

34. The optical assembly according to claim 1, wherein, the first optical element includes an irregular prism configured to reflect the light beam received at the first surface of the first optical element at the side wall to translate the light beam towards the central region of the reflection surface of the second optical element.

35. The optical assembly according to claim 34, wherein the side wall is coated with a reflective film.

36. The optical assembly according to claim 34, wherein, the first surface of the first optical element has an inclination angle configured to refract the light beam from the first surface for total reflection at the side wall.

37. The optical assembly according to claim 34, wherein, the second surface of the first optical element is substantially parallel to a collimating element spaced apart from the optical element to collimate the light beam for reception by the first optical element.

38. The optical assembly according to claim 1, further includes a reflector, the reflector including a transmission region and a reflection region.

39. The optical assembly according to claim 38, further includes a fourth optical element located between the reflector and the first optical element to collimate the light beam for reception by the first optical element.

40. The optical assembly according to claim 38, wherein, the transmission region is substantially disposed at the center of the reflector, the transmission region is configured to transmit the light beam generated by a light source spaced apart from the reflector; and the reflection region is substantially disposed on the peripheral region of the reflector, the reflection region is configured to reflect the return light beam to a receiver spaced apart from the reflector.

41. The optical assembly according to claim 39, further includes: a waveguide positioned between the light source and the fourth optical element, the waveguide being configured to guide the light beam generated by the light source for reception by the transmission region of the reflector to transmit the light beam to the fourth optical element.

42. The optical assembly according to claim 41, wherein, the reflector and the waveguide are integrated to form an optical element in one piece.

43. The optical component according to claim 38, wherein, the reflection area is substantially disposed at the center of the reflector, and the reflection area is configured to reflect the light beam generated by the light source, and the light source is spaced apart from the reflector; and the transmission area is substantially disposed on the peripheral area of the reflector, and the transmission area is configured to transmit the return light beam to be received by a receiver, and the receiver is spaced apart from the reflector.

44. The optical component according to claim 43, further comprising a beam shaper located in front of the light source to focus the light beam onto the reflection area of the reflector.

45. The optical component according to claim 1, further comprising: a fourth optical element located between the light source and the first optical element to collimate the light beam; a waveguide positioned between the light source and the fourth optical element and configured to guide the light beam generated by the light source to reflect the light beam onto the fourth optical element.

46. The optical component according to claim 45, wherein, the waveguide and the fourth optical element are integrated to form a connected optical element.

47. The optical component according to claim 1, further comprising a balancing element attached to the second optical element, and the balancing element is configured to balance the second optical element during rotation about the second axis.

48. The optical component according to claim 47, wherein, the weight of the balancing element is less than the weight of the second optical element.

49. The optical component according to claim 47, wherein, the balancing element includes a first surface attached to the reflective surface of the second optical element.

50. The optical component according to claim 49, wherein, the balancing element includes a second surface connected to an object, and the object is configured to adjust the weight of the balancing element during rotation about the second axis to balance the optical component.

51. The optical component according to claim 50, wherein, the balancing element includes a third surface that can be connected to a motor unit, and the motor unit is configured to rotate the second optical element about the second axis.

52. The optical component according to claim 51, wherein, the second surface of the balancing element is different from the first surface or the third surface of the balancing element and is substantially parallel to the second axis.

53. The optical component according to claim 52, wherein, the object connected to the second surface of the balancing element includes glue attached to the second surface of the balancing element.

54. The optical component according to claim 47, wherein, the second optical element has a first density that is greater than a second density of the balancing element.

55. The optical component according to claim 47, wherein, the central axes of the balancing element and the second optical element are offset from the second axis.

56. The optical component according to claim 47, wherein, The balance element comprises metal, plastic, glass or polymer.

57. The optical component according to claim 1, further comprising a transparent housing for receiving the first optical element and the second optical element.

58. The optical component according to claim 57, wherein, the transparent housing has a conical shape.

59. The optical component according to claim 58, wherein, the transparent housing has a frustoconical shape, and the frustoconical shape has a taper in the range from 1.3 to 1.

7.

60. The optical component according to claim 59, wherein, the transparent housing includes a curved surface.

61. The optical component according to claim 57, wherein, the transparent housing is made of a material with a thickness in the range of 0.8 mm to 1.2 mm.

62. The optical component according to claim 57, wherein, the transparent housing is made of a material with a reflectivity in the range of 1.4 to 1.

7.

63. The optical component according to claim 57, wherein, the transparent housing has a polyhedral conical shape.

64. The optical component according to claim 57, wherein, the transparent housing has a uniform thickness.

65. The optical component according to claim 57, wherein, the transparent housing has a non-uniform thickness.

66. The optical component according to claim 57, wherein, at least a part of the transparent housing has a thickness increasing towards the bottom or the top of the transparent housing.

67. The optical component according to claim 66, wherein, the transparent housing includes at least two parts, wherein one of the at least two parts is configured to refract or displace one of the light beams departing from the second optical element, and the displacement includes vertically or laterally displacing the light beam relative to the position where the light beam would depart from the optical component in the absence of the transparent housing.

68. The optical component according to claim 67, wherein, the transparent housing includes a first part configured to vertically or laterally displace the light beam at the position where the light beam would depart from the optical component in the absence of the first part.

69. The optical component according to claim 68, wherein, the light beam is configured to depart from the optical component at an angle greater than a first target angle.

70. The optical component according to claim 69, wherein, the first part includes a curved surface.

71. The optical component according to claim 69, wherein, the transparent housing includes a second part configured to change the position or orientation of the light beam, and the change includes one of the following: vertically or laterally displacing the light beam relative to the position where the light beam would depart from the optical component in the absence of the second part, or refracting the light beam when the light beam departs from the second part.

72. The optical component according to claim 71, wherein, The light beam is configured to exit the optical component at an angle within a range from a second target angle to the first target angle, where the second target angle is less than the first target angle.

73. The optical component according to claim 72, wherein, the second part has a uniform thickness.

74. The optical component according to claim 72, wherein, the transparent housing includes a third part having a thickness that increases towards the bottom of the transparent housing, and the third part is configured to refract the light beam such that the light beam is configured to exit the optical component at an angle less than the second target angle.

75. The optical component according to claim 1, wherein, the first axis is aligned with the second axis.

76. The optical component according to claim 1, further comprising a collimating element located in front of the first optical element, wherein, the incident angle of the light beam collimated by the collimating element to the first optical element is greater than 0°.

77. The optical component according to claim 76, wherein, the first axis is inclined at a first predetermined angle with respect to the second axis such that the first surface of the first optical element is inclined at the first predetermined angle with respect to the collimating element.

78. The optical component according to claim 76, wherein, the first axis is parallel to or aligned with the second axis, and the first surface of the first optical element is inclined at a second predetermined angle with respect to the collimating element.

79. The optical component according to claim 76, wherein, the first axis is inclined at an angle range from 0° to 90° with respect to the collimating element, and the first surface of the first optical element is substantially parallel to the collimating element.

80. The optical component according to claim 1, wherein, the second optical element rotates about the second axis to scan a field having an azimuth angle in a range from 0° to 360° and / or a pitch angle in a range from -60° to 30°.

81. The optical component according to claim 1, wherein, the first optical element and the second optical element rotate in the same direction to direct the light beam to scan the environment.

82. The optical component according to claim 1, wherein, the first optical element and the second optical element rotate in opposite directions to direct the light beam to scan the environment.

83. The optical component according to claim 1, wherein, when directing the light beam to scan the environment, the first optical element and the second optical element rotate at the same speed.

84. The optical component according to claim 1, wherein, when directing the light beam to scan the environment, the first optical element and the second optical element rotate at different speeds.

85. The optical component according to claim 1, wherein, when the inclination angle of the reflective surface of the second optical element is larger, the field of view that the optical component can scan is lower, and when the inclination angle is smaller, the field of view is higher.

86. The optical component according to claim 1, wherein, The optical component is included in a single - station scanning LiDAR system.

87. The optical component according to claim 1, wherein, the optical component is located on a movable platform that moves in the environment.

88. A rotatable scanner for directing a light beam to scan an environment to detect one or more objects in the environment, comprising: an optical component, the optical component comprising: a reflective optical element that is rotatable about a first axis and is configured to reflect the light beam to the environment through a first side of a reflective surface; a transmissive optical element, the transmissive optical element comprising an irregular prism configured to translate the light beam toward a central region of the reflective surface of the reflective optical element; and a balancing element, the balancing element comprising: a first surface attached to the reflective surface of the reflective optical element at a second side opposite the first side of the reflective surface, and a second surface connected to an object configured to adjust the weight of the balancing element during rotation about the first axis to balance the optical component.

89. The rotatable scanner according to claim 88, wherein, the weight of the balancing element is less than the weight of the reflective optical element.

90. The rotatable scanner according to claim 88, wherein, the balancing element further comprises a third surface connectable to a motor unit configured to rotate the optical component about the first axis.

91. The rotatable scanner according to claim 90, wherein, the second surface of the balancing element is different from the first surface or the third surface of the balancing element.

92. The rotatable scanner according to claim 88, wherein, the second surface of the balancing element is substantially parallel to the first axis.

93. The rotatable scanner according to claim 88, wherein, the object connected to the second surface of the balancing element comprises glue attached to the second surface of the balancing element.

94. The rotatable scanner according to claim 88, wherein, a first density of the reflective optical element is greater than a second density of the balancing element.

95. The rotatable scanner according to claim 88, wherein, a central axis of the optical component is offset from the first axis.

96. The rotatable scanner according to claim 88, wherein, the balancing element comprises metal, plastic, glass, or polymer.

97. The rotatable scanner according to claim 88, wherein, the optical element comprises glass or resin.

98. The rotatable scanner according to claim 88, wherein, the reflective optical element is a prism, the prism comprising: a first surface configured to refract the light beam to the reflective surface; a reflective surface configured to reflect the light beam to a second surface; and the second surface configured to refract the light beam so that the light beam exits the reflective optical element.

99. The rotatable scanner according to claim 98, wherein, the reflective optical element is a triangular prism.

100. The rotatable scanner according to claim 98, wherein, the second surface of the reflective optical element forms an obtuse angle with respect to the first surface of the reflective optical element, and the obtuse angle has a range of 91° to 120°.

101. The rotatable scanner according to claim 88, wherein, the transmissive optical element is spaced apart from the reflective optical element, the transmissive optical element is rotatable about a second axis, and is configured to receive the light beam at a first surface of the transmissive optical element, and refract the light beam through a second surface of the transmissive optical element to the reflective optical element, at which second surface the light beam exits the transmissive optical element.

102. The rotatable scanner according to claim 101, further comprising a reflector, the reflector including a transmissive area and a reflective area.

103. The rotatable scanner according to claim 102, wherein, the transmissive area is substantially disposed at the center of the reflector, the transmissive area is configured to transmit a light beam generated by a light source, the light source being spaced apart from the reflector device; and the reflective area is substantially disposed on a peripheral area of the reflector, the reflective area is configured to reflect a return light beam towards a receiver, the receiver being spaced apart from the reflector.

104. The rotatable scanner according to claim 102, wherein, the reflective area is substantially disposed at the center of the reflector, the reflective area is configured to reflect a light beam generated by a light source, the light source being spaced apart from the reflector; and the transmissive area is substantially disposed on a peripheral area of the reflector, the transmissive area is configured to transmit the return light beam for reception by a receiver, the receiver being spaced apart from the reflector.

105. The rotatable scanner according to claim 102, further comprising a collimating element located between the reflector and the transmissive optical element to collimate the light beam for reception by the transmissive optical element.

106. The rotatable scanner according to claim 105, wherein, the transmissive optical element is positioned to be inclined with respect to the collimating element.

107. The rotatable scanner according to claim 101, further comprising a transparent housing for accommodating the transmissive optical element and the reflective optical element.

108. The rotatable scanner according to claim 88, wherein, the rotatable scanner is configured to scan a field having an azimuth angle in the range from 0° to 360° and / or a pitch angle in the range from -60° to 30°.

109. A method for guiding a light beam to scan an environment to detect one or more objects in the environment, comprising: rotating a first optical element about a first axis and rotating a second optical element about a second axis, the first optical element being spaced apart from the second optical element; guiding the light beam from the first optical element to a reflective surface of the second optical element; and Reflecting the light beam through the reflection surface to transmit it into the environment; wherein, the first optical element includes an irregular prism configured to translate the light beam towards a central region of the reflection surface of the second optical element.

110. The method according to claim 109, wherein, the second optical element includes a prism, and wherein the method further includes: Refracting the light beam through a first surface of the second optical element to a central region of the reflection surface of the second optical element; Reflecting the light beam through the reflection surface to a second surface of the second optical element; and When the second optical element rotates about the second axis, refracting the light beam through the second surface into the environment.

111. The method according to claim 109, further including: Collimating the light beam through a collimating element to be received by the first optical element.

112. The method according to claim 111, wherein, the method further includes: Transmitting the light beam from a light source through a center of a third optical element to the collimating element, and Reflecting a return light beam to a receiver through a reflection region on a peripheral region of the third optical element.

113. The method according to claim 111, wherein, the method further includes: Reflecting the light beam generated by the light source through a reflection region at the center of the third optical element to the collimating element; and Transmitting the return light beam to the receiver through a transmission region on a peripheral region of the third optical element.

114. The method according to claim 109, wherein, the first axis is aligned with the second axis.

115. The method according to claim 109, wherein, the first axis is inclined relative to the second axis.

116. The method according to claim 109, wherein, the first optical element and the second optical element rotate in the same direction to guide the light beam to scan the environment.

117. The method according to claim 109, wherein, the first optical element and the second optical element rotate in opposite directions to guide the light beam to scan the environment.

118. The method according to claim 109, wherein, the first optical element and the second optical element rotate at the same speed to guide the light beam to scan the environment.

119. The method according to claim 109, wherein, the first optical element and the second optical element rotate at different speeds to guide the light beam to scan the environment.

120. The method according to claim 109, wherein, the first optical element and the second optical element are included in a single - station scanning LiDAR system.

121. The method according to claim 109, wherein, the first optical element and the second optical element are located on a movable platform moving in the environment.

122. A LiDAR system, including: A light source configured to emit a pulsed laser beam; A scanning optical assembly configured to direct the pulsed laser beam to scan an environment to detect one or more objects in the environment, the scanning optical assembly comprising: A first optical element rotatable about a first axis and configured to receive a light beam at a first surface of the first optical element and refract the light beam through a second surface of the first optical element, the light beam exiting the first optical element at the second surface; and A second optical element spaced apart from the first optical element and rotatable about a second axis, the second optical element positioned to reflect the light beam through a reflective surface of the second optical element into the environment to detect the one or more objects; a receiver configured to receive a return light beam reflected by the one or more objects in the environment via the scanning optical assembly; Wherein the first optical element includes an irregular prism configured to translate the light beam toward a central region of the reflective surface of the second optical element.

123. The LiDAR system according to claim 122, Wherein, The second optical element further includes a first surface configured to refract the light beam to the reflective surface of the second optical element.

124. The LiDAR system according to claim 123, Wherein, The second optical element further includes a second surface configured to refract the light beam reflected by the reflective surface into the environment, the light beam exiting the second optical element from the second surface.

125. The LiDAR system according to claim 124, Wherein, The second optical element includes a triangular prism.

126. The LiDAR system according to claim 124, Wherein, The second surface of the second optical element forms an obtuse angle with respect to the first surface of the second optical element, the obtuse angle having a range of 91° to 120°.

127. The LiDAR system according to claim 122, Wherein, The length of one side of the irregular prism is in the range of 6 mm to 12 mm.

128. The LiDAR system according to claim 122, Wherein, The first surface of the irregular prism has a first tilt angle in the range from 15° to 35°.

129. The LiDAR system according to claim 122, Wherein, The scanning optical assembly further includes a reflector including a transmissive region and a reflective region.

130. The LiDAR system according to claim 129, Wherein, The transmissive region is substantially disposed at the center of the reflector and is configured to transmit a light beam generated by a light source spaced apart from the reflector; and the reflective region is substantially disposed on a peripheral region of the reflector and is configured to reflect the return light beam toward a receiver spaced apart from the reflector.

131. The LiDAR system according to claim 129, Wherein, the reflection area is substantially disposed at the center of the reflector, and the reflection area is configured to reflect the light beam generated by the light source, and the light source is spaced apart from the reflector; and the transmission area is substantially disposed on the peripheral area of the reflector, and the transmission area is configured to transmit the return light beam to be received by the receiver, and the receiver is spaced apart from the reflector.

132. The LiDAR system according to claim 129, wherein, the first optical element is positioned to be inclined with respect to the reflector to collimate the light beam to be received by the first optical element.

133. The LiDAR system according to claim 122, wherein, the first axis is aligned with the second axis.

134. The LiDAR system according to claim 133, further comprising a collimating element located in front of the first optical element, wherein, the incident angle of the light beam collimated by the collimating element to the first optical element is greater than 0°.

135. The LiDAR system according to claim 134, wherein, the first axis is inclined with respect to the second axis at a first predetermined angle such that the first surface of the first optical element is inclined with respect to the collimating element at the first predetermined angle.

136. The LiDAR system according to claim 134, wherein, the first axis is parallel to or aligned with the second axis, and the first surface of the first optical element is inclined with respect to the collimating element at a second predetermined angle.

137. The LiDAR system according to claim 134, wherein, the first axis is inclined with respect to the collimating element at an angle range from 0° to 90°, and the first surface of the first optical element is substantially parallel to the collimating element.

138. The LiDAR system according to claim 122, wherein, the scanning optical assembly further comprises a balancing element attached to the second optical element, and the balancing element is configured to balance the second optical element during rotation about the second axis.

139. The LiDAR system according to claim 138, wherein, the balancing element includes a first surface attached to the reflective surface of the second optical element.

140. The LiDAR system according to claim 139, wherein, the balancing element includes a second surface connected to an object, and the object is configured to adjust the weight of the balancing element during rotation about the second axis to balance the optical assembly.

141. The LiDAR system according to claim 122, wherein, the scanning optical assembly further comprises a transparent housing for accommodating the first optical element and the second optical element.

142. The LiDAR system according to claim 141, wherein, the transparent housing has a conical shape or a curved surface.

143. The LiDAR system according to claim 141, wherein, The transparent housing is made of a material with a thickness in the range of 0.8 mm to 1.2 mm, and / or a reflectivity in the range of 1.4 to 1.

7.

144. The LiDAR system according to claim 141, wherein, the transparent housing has a uniform thickness.

145. The LiDAR system according to claim 141, wherein, the transparent housing has a non-uniform thickness.

146. The LiDAR system according to claim 141, wherein, at least a portion of the transparent housing has a thickness that increases towards the bottom or top of the transparent housing.

147. The LiDAR system according to claim 144, wherein, the transparent housing includes at least two parts, one of the at least two parts being configured to refract or shift one of the light beams guided from the second optical element, wherein the shifting includes shifting the light beam vertically or laterally relative to the position where the light beam would exit the optical assembly in the absence of the transparent housing.

148. The LiDAR system according to claim 145, wherein, the transparent housing includes a first part configured to shift the light beam vertically or laterally at the position where the light beam would exit the optical assembly in the absence of the first part.

149. The LiDAR system according to claim 148, wherein, the light beam is configured to exit the optical assembly at an angle greater than a first target angle.

150. The LiDAR system according to claim 149, wherein, the transparent housing includes a second part configured to change the position or orientation of the light beam, wherein the change includes one of the following: shifting the light beam vertically or laterally relative to the position where the light beam would exit the optical assembly in the absence of the second part, or refracting the light beam when the light beam exits the second part.

151. The LiDAR system according to claim 150, wherein, the light beam is configured to exit the optical assembly at an angle in the range from a second target angle to the first target angle.

152. The LiDAR system according to claim 151, wherein, the second target angle is greater than the first target angle.

153. The LiDAR system according to claim 151, wherein, the second target angle is less than the first target angle.

154. The LiDAR system according to claim 153, wherein, the first target angle is a positive angle and the second target angle is a negative angle.

155. The LiDAR system according to claim 151, wherein, the second part has a uniform thickness.

156. The LiDAR system according to claim 151, wherein, the transparent housing includes a third part having a thickness that increases towards the bottom of the transparent housing, the third part being configured to refract the light beam such that the light beam is configured to exit the optical assembly at an angle less than the second target angle.

157. The LiDAR system according to claim 122, wherein, the scanning optical assembly is configured to scan a field having an azimuth angle in the range from 0° to 360° and / or an elevation angle in the range from -60° to 30°.

158. A LiDAR system, comprising: a light source configured to emit a pulsed laser beam; a scanning optical assembly configured to direct the pulsed laser beam to scan an environment to detect one or more objects in the environment, the scanning optical assembly comprising: a reflective optical element rotatable about a first axis and configured to reflect the beam into the environment through a first side of a reflective surface; a transmissive optical element including an irregular prism configured to translate the beam towards a central region of the reflective surface of the reflective optical element; and a balancing element comprising: a first surface attached to the reflective surface of the reflective optical element at a second side opposite the first side of the reflective surface, and a second surface connected to an object configured to adjust the weight of the balancing element during rotation about the first axis to balance the optical assembly; a receiver configured to receive, via the scanning optical assembly, one or more return beams reflected by the one or more objects in the environment.

159. The LiDAR system according to claim 158, wherein, the weight of the balancing element is less than the weight of the reflective optical element.

160. The LiDAR system according to claim 158, wherein, the balancing element further includes a third surface connectable to a motor unit configured to rotate the scanning optical assembly about the first axis.

161. The LiDAR system according to claim 158, wherein, the second surface of the balancing element is substantially parallel to the first axis.

162. The LiDAR system according to claim 158, wherein, the object connected to the second surface of the balancing element includes glue attached to the second surface of the balancing element.

163. The LiDAR system according to claim 158, wherein, a first density of the reflective optical element is greater than a second density of the balancing element.

164. The LiDAR system according to claim 158, wherein, a central axis of the optical assembly is offset from the first axis.

165. The LiDAR system according to claim 158, wherein, the balancing element includes metal, plastic, glass or polymer.

166. The LiDAR system according to claim 158, wherein, the reflective optical element includes glass or resin.

167. The LiDAR system according to claim 158, wherein, the reflective optical element is a prism, and the prism includes: A first surface configured to refract the light beam onto the reflective surface; A reflective surface configured to reflect the light beam onto a second surface; and The second surface configured to refract the light beam such that the light beam exits the reflective optical element.

168. The LiDAR system according to claim 167, wherein, The reflective optical element is a triangular prism.

169. The LiDAR system according to claim 167, wherein, The second surface of the reflective optical element forms an obtuse angle with respect to the first surface of the reflective optical element, and the obtuse angle has a range of 91° to 120°.

170. The LiDAR system according to claim 158, wherein, The transmissive optical element is spaced apart from the reflective optical element, the transmissive optical element is rotatable about a second axis, and is configured to receive the light beam at a first surface of the transmissive optical element and refract the light beam through a second surface of the transmissive optical element onto the reflective optical element, at which second surface the light beam exits the transmissive optical element.

171. The LiDAR system according to claim 170, wherein, The first axis is aligned with the second axis.

172. The LiDAR system according to claim 171, wherein, It further includes a collimating element located in front of the transmissive optical element, wherein the incident angle of the light beam collimated by the collimating element onto the transmissive optical element is greater than 0°.

173. The LiDAR system according to claim 172, wherein, The first axis is inclined at a first predetermined angle with respect to the second axis such that the first surface of the transmissive optical element is inclined at the first predetermined angle with respect to the collimating element.

174. The LiDAR system according to claim 172, wherein, The first axis is parallel to or aligned with the second axis, and the first surface of the transmissive optical element is inclined at a second predetermined angle with respect to the collimating element.

175. The LiDAR system according to claim 172, wherein, The first axis is inclined at an angle range from 0° to 90° with respect to the collimating element, and the first surface of the transmissive optical element is substantially parallel to the collimating element.

176. The LiDAR system according to claim 158, wherein, The length of one side of the irregular prism is in the range of 6 mm to 12 mm.

177. The LiDAR system according to claim 158, wherein, The first surface of the irregular prism has a first inclination angle in the range from 15° to 35°.

178. The LiDAR system according to claim 171, wherein, It further includes a reflector, and the reflector includes a transmissive region and a reflective region.

179. The LiDAR system according to claim 178, wherein, The transmission region is substantially disposed at the center of the reflector and is configured to transmit the light beam generated by the light source; and the reflection region is substantially disposed on the peripheral region of the reflector and is configured to reflect the return light beam to the receiver.

180. The LiDAR system according to claim 178, wherein, the reflection region is substantially disposed at the center of the reflector and is configured to reflect the light beam generated by the light source; and the transmission region is substantially disposed on the peripheral region of the reflector and is configured to transmit the return light beam to the receiver.

181. The LiDAR system according to claim 178, further comprising a collimating element located between the reflector and the transmission optical element to collimate the light beam for reception by the transmission optical element.

182. The LiDAR system according to claim 181, wherein, the transmission optical element is positioned to be inclined relative to the collimating element.

183. The LiDAR system according to claim 171, further comprising a transparent housing for accommodating the transmission optical element and the reflection optical element.

184. The LiDAR system according to claim 183, wherein, the transparent housing has a conical shape or a curved surface.

185. The LiDAR system according to claim 183, wherein, the transparent housing is made of a material having a thickness in the range of 0.8 mm to 1.2 mm, and / or a reflectivity in the range of 1.4 to 1.

7.

186. The LiDAR system according to claim 183, wherein, the transparent housing has a uniform thickness.

187. The LiDAR system according to claim 183, wherein, the transparent housing has a non-uniform thickness.

188. The LiDAR system according to claim 183, wherein, at least a portion of the transparent housing has a thickness that increases towards the bottom or top of the transparent housing.

189. The LiDAR system according to claim 188, wherein, the transparent housing includes at least two portions, wherein one of the at least two portions is configured to refract or displace one of the light beams from the reflection optical element, wherein the displacement includes displacing the light beam vertically or laterally relative to the position where the light beam would exit the optical assembly in the absence of the transparent housing.

190. The LiDAR system according to claim 189, wherein, the transparent housing includes a first portion configured to refract the light beam exiting the optical assembly at a pitch angle greater than a first target angle.

191. The LiDAR system according to claim 190, wherein, the transparent housing includes a second portion configured to refract or displace one of the light beams guided from the reflection optical element, wherein the displacement includes displacing the light beam vertically or laterally relative to the position where the light beam would exit the optical assembly in the absence of the transparent housing. The LiDAR system according to claim 190, wherein, the light beam is configured to leave the optical component at a pitch angle within a range from a second angle to a first angle. The LiDAR system according to claim 191, wherein, the second part has a uniform thickness. The LiDAR system according to claim 192, wherein, the transparent housing includes a third part having a thickness increasing towards the bottom of the transparent housing, and the third part is configured to refract the light beam such that the light beam is configured to leave the optical component at an angle less than the second angle. The LiDAR system according to claim 170, wherein, the scanning optical component is configured to scan a field having an azimuth angle in a range from 0° to 360° and / or a pitch angle in a range from -60° to 30°. A mobile platform, comprising: an optical component located on the mobile platform and configured to direct a light beam to scan an environment to detect one or more objects in the environment, the optical component including: a first optical element rotatable about a first axis and configured to receive the light beam at a first surface of the first optical element and refract the light beam through a second surface of the first optical element, the light beam leaving the first optical element at the second surface; and a second optical element spaced apart from the first optical element and rotatable about a second axis, the second optical element being positioned to reflect the light beam to the environment through a reflective surface of the second optical element to detect the one or more objects; a propulsion system configured to propel the mobile platform in the environment; wherein the first optical element includes an irregular prism configured to translate the light beam towards a central region of the reflective surface of the second optical element. The mobile platform according to claim 196, wherein, the second optical element further includes a first surface configured to refract the light beam to the reflective surface of the second optical element. The mobile platform according to claim 197, wherein, the light beam is refracted by the first surface of the second optical element to a central region of the reflective surface of the second optical element. The mobile platform according to claim 197, wherein, the second optical element further includes a second surface configured to refract the light beam reflected by the reflective surface to the environment, and the light beam leaves the second optical element from the second surface. The mobile platform according to claim 199, wherein, the second optical element includes a triangular prism. The mobile platform according to claim 200, wherein, The second surface of the second optical element forms an obtuse angle with respect to the first surface of the second optical element, and the obtuse angle has a range of 91° to 120°.

202. The movable platform according to claim 196, wherein, the length of one side of the irregular prism is in the range of 6 mm to 12 mm.

203. The movable platform according to claim 196, wherein, the first surface of the irregular prism has a first tilt angle in the range from 15° to 35°.

204. The movable platform according to claim 196, wherein, the optical assembly further includes a reflector, and the reflector includes a transmission region and a reflection region.

205. The movable platform according to claim 204, wherein, the transmission region is substantially disposed at the center of the reflector, the transmission region is configured to transmit a light beam generated by a light source, and the light source is spaced apart from the reflector; and the reflection region is substantially disposed on a peripheral region of the reflector and is configured to reflect a return light beam to a receiver, and the receiver is spaced apart from the reflector.

206. The movable platform according to claim 204, wherein, the reflection region is substantially disposed at the center of the reflector, the reflection region is configured to reflect the light beam generated by the light source, and the light source is spaced apart from the reflector; and the transmission region is substantially disposed on a peripheral region of the reflector, and the transmission region is configured to transmit the return light beam to be received by a receiver, and the receiver is spaced apart from the reflector.

207. The movable platform according to claim 204, wherein, the first optical element is positioned to be inclined with respect to the reflector to collimate the light beam for being received by the first optical element.

208. The movable platform according to claim 204, wherein, the first axis is aligned with the second axis.

209. The movable platform according to claim 204, wherein, it further includes a collimating element located in front of the first optical element, and the incident angle of the light beam collimated by the collimating element to the first optical element is greater than 0°.

210. The movable platform according to claim 209, wherein, the first axis is inclined with respect to the second axis.

211. The movable platform according to claim 209, wherein, the first axis is parallel to or aligned with the second axis, and the first surface of the first optical element is inclined with respect to the collimating element at a second predetermined angle.

212. The movable platform according to claim 209, wherein, the first axis is inclined with respect to the collimating element at an angle range from 0° to 90°, and the first surface of the first optical element is substantially parallel to the collimating element.

213. The movable platform according to claim 196, wherein, The optical component further includes a balancing element, the balancing element being attached to the second optical element, and the balancing element being configured to balance the second optical element during rotation about the second axis.

214. The movable platform according to claim 213, wherein, the balancing element includes a first surface attached to the reflective surface of the second optical element.

215. The movable platform according to claim 213, wherein, the balancing element includes a second surface connected to an object, the object being configured to adjust the weight of the balancing element during rotation about the second axis to balance the optical component.

216. The movable platform according to claim 196, wherein, the optical component further includes a transparent housing for accommodating the first optical element and the second optical element.

217. The movable platform according to claim 216, wherein, the transparent housing has a conical shape or a curved surface.

218. The movable platform according to claim 216, wherein, the transparent housing is made of a material with a thickness in the range of 0.8 mm to 1.2 mm, and / or a reflectivity in the range of 1.4 to 1.

7.

219. The movable platform according to claim 216, wherein, the transparent housing has a uniform thickness.

220. The movable platform according to claim 216, wherein, the transparent housing has a non-uniform thickness.

221. The movable platform according to claim 216, wherein, at least a portion of the transparent housing has a thickness that increases towards the bottom or top of the transparent housing.

222. The movable platform according to claim 221, wherein, the transparent housing includes at least two portions, one of the at least two portions being configured to refract or displace one of the light beams departing from the second optical element, wherein the displacement includes vertically or laterally displacing the light beam relative to the position at which the light beam would depart the optical component in the absence of the transparent housing.

223. The movable platform according to claim 222, wherein, the transparent housing includes a first portion configured to refract the light beam departing from the optical component at a pitch angle higher than a first target angle.

224. The movable platform according to claim 222, wherein, it includes a second portion configured to refract or displace one of the light beams guided from the second optical element, wherein the displacement includes vertically or laterally displacing the light beam relative to the position at which the light beam would depart the optical component in the absence of the transparent housing.

225. The movable platform according to claim 222, wherein, the light beam is configured to depart the optical component at a pitch angle within a range from a second angle to a first angle.

226. The movable platform according to claim 224, wherein, the second portion has a uniform thickness.

227. The movable platform according to claim 225, wherein, The transparent housing includes a third portion having a thickness that increases towards the bottom of the transparent housing, and the third portion is configured to refract the light beam such that the light beam is configured to exit the optical component at an angle less than the second angle.

228. The mobile platform according to claim 196, further comprising: a light source configured to emit a light beam received by the optical component; a receiver configured to receive, via the optical component, a return light beam reflected by one or more objects in the environment.

229. The mobile platform according to claim 196, wherein, the optical component is configured to scan a field around the mobile platform, the field having an azimuth angle in the range from 0° to 360°, and / or an elevation angle in the range from -60° to 30°.

230. A mobile platform, comprising: a scanning optical component located on the mobile platform and configured to direct a pulsed laser light beam to scan the environment to detect one or more objects in the environment, the optical component comprising: a reflective optical element rotatable about a first axis and configured to reflect the light beam to the environment through a first side of a reflective surface; a transmissive optical element including an irregular prism configured to translate the light beam towards a central region of the reflective surface of the reflective optical element; and a balancing element comprising: a first surface attached to the reflective surface of the reflective optical element at a second side opposite the first side of the reflective surface, and a second surface connected to an object configured to adjust the weight of the balancing element during rotation about the first axis to balance the optical component; and a propulsion system configured to propel the mobile platform in the environment.

231. The mobile platform according to claim 230, wherein, the weight of the balancing element is less than the weight of the reflective optical element.

232. The mobile platform according to claim 230, wherein, the balancing element includes a third surface connectable to a motor unit configured to rotate the scanning optical component about the first axis.

233. The mobile platform according to claim 230, wherein, the second surface of the balancing element is substantially parallel to the first axis.

234. The mobile platform according to claim 230, wherein, the object connected to the second surface of the balancing element includes glue attached to the second surface of the balancing element.

235. The mobile platform according to claim 230, wherein, a first density of the reflective optical element is greater than a second density of the balancing element.

236. The mobile platform according to claim 230, wherein, a central axis of the optical component is offset from the first axis.

237. The mobile platform according to claim 230, Among them, the balance element includes metal, plastic, glass or polymer.

238. The movable platform according to claim 230, wherein, the optical element includes glass or resin.

239. The movable platform according to claim 230, wherein, the reflective optical element is a prism, and the prism includes: a first surface configured to refract the light beam to the reflective surface; a reflective surface configured to reflect the light beam to a second surface; and the second surface configured to refract the light beam so that the light beam exits the reflective optical element.

240. The movable platform according to claim 239, wherein, the reflective optical element is a triangular prism.

241. The movable platform according to claim 239, wherein, the second surface of the reflective optical element forms an obtuse angle with respect to the first surface of the reflective optical element, and the obtuse angle has a range of 91° to 120°.

242. The movable platform according to claim 230, wherein, the transmissive optical element is spaced apart from the reflective optical element, the transmissive optical element is rotatable about a second axis, and is configured to receive the light beam at a first surface of the transmissive optical element and refract the light beam through a second surface of the transmissive optical element to the reflective optical element, at which second surface the light beam exits the transmissive optical element.

243. The movable platform according to claim 242, wherein, the first axis is aligned with the second axis.

244. The movable platform according to claim 242, wherein, the first axis is inclined with respect to the second axis.

245. The movable platform according to claim 230, wherein, the length of one side of the irregular prism is in the range of 6 mm to 12 mm.

246. The movable platform according to claim 230, wherein, the first surface of the irregular prism has a first inclination angle in the range from 15° to 35°.

247. The movable platform according to claim 242, wherein, it further includes a reflector, and the reflector includes a transmissive area and a reflective area.

248. The movable platform according to claim 247, wherein, the transmissive area is substantially disposed at the center of the reflector and is configured to transmit the light beam generated by the light source; and the reflective area is substantially disposed on the peripheral area of the reflector and is configured to reflect the return light beam to the receiver.

249. The movable platform according to claim 247, wherein, the reflective area is substantially disposed at the center of the reflector and is configured to reflect the light beam generated by the light source; and the transmissive area is substantially disposed on the peripheral area of the reflector and is configured to transmit the return light beam to the receiver. The movable platform according to claim 247 further includes a collimating element located between the reflector and the collimating element of the transmissive optical element to collimate the light beam for reception by the transmissive optical element.

251. The movable platform according to claim 250, wherein, the transmissive optical element is positioned to be inclined relative to the collimating element.

252. The movable platform according to claim 242 further includes a transparent housing for accommodating the transmissive optical element and the reflective optical element.

253. The movable platform according to claim 252, wherein, the transparent housing has a conical shape or a curved surface.

254. The movable platform according to claim 252, wherein, the transparent housing is made of a material having a thickness in the range of 0.8 mm to 1.2 mm and / or a reflectivity in the range of 1.4 to 1.

7.

255. The movable platform according to claim 252, wherein, the transparent housing has a uniform thickness.

256. The movable platform according to claim 252, wherein, the transparent housing has a non-uniform thickness.

257. The movable platform according to claim 252, wherein, at least a portion of the transparent housing has a thickness that increases towards the bottom or top of the transparent housing.

258. The movable platform according to claim 257, wherein, the transparent housing includes at least two portions, wherein one of the at least two portions is configured to refract or displace one of the light beams from the reflective optical element, wherein the displacement includes displacing the light beam vertically or laterally relative to the position where the light beam would exit the optical assembly in the absence of the transparent housing.

259. The movable platform according to claim 258, wherein, the transparent housing includes a first portion configured to refract the light beam exiting the optical assembly at a pitch angle greater than a first target angle.

260. The movable platform according to claim 259, wherein, the transparent housing includes a second portion configured to refract or displace one of the light beams guided from the reflective optical element, wherein the displacement includes displacing the light beam vertically or laterally relative to the position where the light beam would exit the optical assembly in the absence of the transparent housing.

261. The movable platform according to claim 260, wherein, the light beam is configured to exit the optical assembly at a pitch angle within a range from a second angle to a first angle.

262. The movable platform according to claim 261, wherein, the second portion has a uniform thickness.

263. The movable platform according to claim 261, wherein, the transparent housing includes a third portion having a thickness that increases towards the bottom of the transparent housing, the third portion being configured to refract the light beam from the reflective optical element to a field having a pitch angle lower than the second angle.

264. The movable platform according to claim 230, further comprising: a light source configured to emit the pulsed laser beam received by the scanning optical assembly; and a receiver configured to receive, via the scanning optical assembly, one or more return beams reflected by one or more objects in the environment.

265. The movable platform according to claim 252, wherein the scanning optical assembly is configured to scan a field having an azimuth angle in a range from 0° to 360° and / or an elevation angle in a range from -60° to 30°.

Images