Laser radar

Abstract

The present disclosure provides a laser radar, comprising: an emitter adapted to emit probe light; the receiver is suitable for receiving echo light generated after the detection light is reflected by an object; the window is suitable for enabling the detection light to be emitted to the external space of the laser radar, the window is also suitable for enabling the echo light to be emitted to the internal space of the laser radar, and the window is provided with an inner surface facing the internal space of the laser radar; and the air blower is suitable for blowing air to the inner surface of the window.

Description

Technical Field

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

[0002] LiDAR is an advanced detection method that combines laser technology with photoelectric detection technology. Due to its advantages such as high resolution, good concealment, strong resistance to active interference, good low-altitude detection performance, small size and light weight, LiDAR is widely used in fields such as autonomous driving, transportation communication, drones, intelligent robots, energy security monitoring, and resource exploration.

[0003] With the rise of assisted driving and autonomous driving technologies, lidar (LiDAR) is receiving increasing attention as a crucial detection component. LiDAR detects information such as the position and speed of objects by emitting laser beams. Currently, lidar is typically installed on the exterior of the vehicle's passenger compartment, such as on the roof or side. To ensure proper operation, lidar usually requires waterproofing and sealing.

[0004] However, when lidar is stored in a high-temperature and high-humidity environment for a long time and then transferred to a low-temperature environment, fogging will occur inside the lidar window, affecting the laser transmission and reception efficiency and causing performance degradation. As the waterproof and sealing performance of lidar improves, fogging inside the window caused by changes in ambient temperature is becoming more and more likely to occur. Utility Model Content

[0005] The problem addressed in this disclosure is how to overcome the fogging problem inside the lidar window.

[0006] To address the aforementioned problems, this disclosure provides a lidar, comprising:

[0007] A transmitter adapted to emit a probe light; a receiver adapted to receive the echo light generated after the probe light is reflected by an object; a window adapted to allow the probe light to exit into the external space of the lidar, and the window also adapted to allow the echo light to enter the internal space of the lidar, the window having an inner surface facing the internal space of the lidar; and a blower adapted to blow air onto the inner surface of the window.

[0008] Optionally, the blower is a fan.

[0009] Optionally, the air outlet of the fan is provided with multiple grilles, which are arranged in parallel.

[0010] Optionally, the diameter of the fan is less than 1 cm.

[0011] Optionally, the lidar is a solid-state lidar.

[0012] Optionally, it also includes: a scanning mirror, the scanning mirror including a reflector that rotates about a pivot axis, the reflector including a reflective surface for reflecting at least one of the probe light and the echo light; the blower including a fan blade, one end of the fan blade being fixedly connected to the pivot axis, and the line connecting the one end and the other end of the fan blade intersecting the reflective surface.

[0013] Optionally, in a plane perpendicular to the axis of rotation, the distance between one end of the fan blade and the other end is not greater than the maximum distance between the reflective surface and the axis of rotation.

[0014] Optionally, the blower includes at least two fan blades; the at least two fan blades are distributed within a preset angle range.

[0015] Optionally, the at least two fan blades are evenly distributed within a preset angle range.

[0016] Optionally, the included angle between adjacent blades is equal.

[0017] Optionally, in the scanning mirror, the reflecting mirror rotates unidirectionally around the rotating axis; the preset range is 360°.

[0018] Optionally, in the scanning mirror, the reflecting mirror reciprocates around the rotating axis; the preset range includes: the window opening angle, which is the central angle of the window relative to the rotating axis.

[0019] Optionally, the scanning mirror further includes a drive motor adapted to drive the reflector to move about the rotating axis.

[0020] Compared with the prior art, the technical solution disclosed herein has the following advantages:

[0021] In this disclosed technical solution, the blower blows air onto the inner surface of the window, which can effectively remove or suppress fog inside the window and effectively improve the problem of fogging inside the lidar window. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of this disclosure or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort. The drawings are used to provide a further understanding of this disclosure and constitute a part of the specification. They are used together with the embodiments of this disclosure to explain this disclosure and do not constitute a limitation of this disclosure. In the drawings:

[0023] Figure 1 This is a schematic diagram of the structure of the lidar in some embodiments of this disclosure;

[0024] Figure 2 This is a schematic diagram of the structure of the fan outlet in some embodiments of this disclosure;

[0025] Figure 3 This is a side view schematic diagram of the lidar structure in some embodiments of this disclosure. Detailed Implementation

[0026] In the following description, only certain exemplary embodiments are briefly described. As those skilled in the art will recognize, the described embodiments can be modified in various ways without departing from the spirit or scope of this disclosure. Therefore, the drawings and description are to be considered exemplary in nature and not restrictive.

[0027] In the description of this disclosure, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing this disclosure and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this disclosure. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of this disclosure, "a plurality of" means two or more, unless otherwise explicitly specified.

[0028] In the description of this disclosure, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linkage" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections, electrical connections, or connections that allow for communication; they can refer to direct connections or indirect connections through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this disclosure according to the specific circumstances.

[0029] In this disclosure, unless otherwise expressly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0030] The following disclosure provides numerous different embodiments or examples for implementing various structures of this disclosure. To simplify the disclosure, specific examples of components and arrangements are described below. These are merely examples and are not intended to limit the scope of this disclosure. Furthermore, reference numerals and / or letters may be repeated in different examples; such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed. In addition, various specific examples of processes and materials are provided in this disclosure, but those skilled in the art will recognize the application of other processes and / or the use of other materials.

[0031] In existing technologies, a heating film or heating wire is typically placed inside the viewing window of a lidar system to heat the window and improve the fogging problem. However, this solution is expensive and detrimental to the cost control of lidar systems.

[0032] To address the aforementioned technical problem, this disclosure provides a lidar, comprising: a transmitter, a receiver, a viewing window, and a blower.

[0033] The transmitter is adapted to emit a probe light. The receiver is adapted to receive the echo light generated after the probe light is reflected by an object.

[0034] The window is adapted to allow the probe light to exit into the external space of the lidar, and the window is also adapted to allow the echo light to enter into the internal space of the lidar. The window has an inner surface facing the internal space of the lidar.

[0035] The blower is adapted to blow air onto the inner surface of the window.

[0036] The technical solution disclosed herein is that the blower blows air onto the inner surface of the window, which can effectively remove or suppress fog inside the window and effectively improve the problem of fogging inside the lidar window.

[0037] To make the above-mentioned objects, features and advantages of this disclosure more apparent and understandable, specific embodiments of this disclosure will be described in detail below with reference to the accompanying drawings.

[0038] refer to Figure 1 The diagram shows a schematic representation of the structure of a lidar in some embodiments of this disclosure.

[0039] The lidar includes: a transmitter, a receiver (not shown in the figure), a viewing window 120, and a blower 130.

[0040] The transmitter is adapted to emit probe light.

[0041] The receiver is adapted to receive the echo light generated after the probe light is reflected by an object.

[0042] The window 120 is adapted to allow the probe light to exit into the external space of the lidar, and the window 120 is also adapted to allow the echo light to enter into the internal space of the lidar. The window 120 has an inner surface facing the internal space of the lidar.

[0043] The blower 130 is adapted to blow air onto the inner surface 121 of the window 120.

[0044] The transmitter includes at least one laser. The laser may include one or more of the following: vertical-cavity surface-emitting lasers (VCSELs), edge-emitting lasers (EELs), distributed feedback lasers (DFBs), fiber lasers, etc.

[0045] The receiver includes at least one detector. The detector may include one or more of the following: single photonavalanche diode (SPAD), avalanche photodiode (APD), silicon photomultiplier (SiPM).

[0046] Window 120 is adapted to allow the transmission of the probe light and the echo light.

[0047] The surface of the window 120 facing the internal space of the lidar is called the inner surface 121. The surface of the window 120 facing the external space of the lidar is called the outer surface 122. Detection light is transmitted through the window 120 along the direction from the inner surface 121 to the outer surface 122; echo light is transmitted through the window 120 along the direction from the outer surface 122 to the inner surface 121. When the inner surface 121 of the window 120 fogs up, it may block part of the optical path of the detection light or echo light, affecting the lidar's laser transceiver efficiency or detection accuracy. For example, fog may reflect part of the detection light or echo light, or refract part of the detection light or echo light into a position deviating from the preset detection angle.

[0048] The blower 130 blows air toward the inner surface 121 of the window 120 to improve air circulation near the inner surface 121 of the window 120, thereby eliminating fog.

[0049] In some embodiments of this disclosure, the lidar is a solid-state lidar. The solid-state lidar does not include rotating components. A blower 130 is provided within the solid-state lidar to effectively improve airflow within its internal space. The blower 130 can improve airflow near the inner surface of the viewing window 120 in the solid-state lidar, effectively eliminating fogging on the inner surface 121 of the viewing window 120.

[0050] In some embodiments of this disclosure, the blower 130 is a fan. The blower 130 can be a common mechanical fan. Common mechanical fans are inexpensive and can effectively control the overall cost of the lidar.

[0051] In some embodiments, the diameter D of the fan is less than 1 cm. (Refer to the reference...) Figure 2 , Figure 2 The diagram shows a schematic representation of the fan's outlet in some embodiments of this disclosure. Controlling the diameter D of the fan's outlet 223 can effectively reduce the space occupied by the fan within the lidar, thus facilitating the control of the lidar's size.

[0052] In some embodiments, the fan outlet 223 is provided with a plurality of slats 224. The slats 224 are used to change the airflow direction. The plurality of slats 224 are arranged in parallel. Figure 2 As shown, the parallel grilles 224 are suitable for controlling the airflow direction of the fan, so that the fan blows air in a preset direction. The orientation of the fan outlet 223 and the orientation of the grilles 224 can direct the fan's airflow towards the inner surface of the window, which can improve the fogging problem on the inner surface.

[0053] refer to Figure 3 The diagram shows a schematic representation of the lidar structure in some other embodiments of this disclosure.

[0054] In some embodiments of this disclosure, the lidar is a semi-solid-state lidar or a hybrid solid-state lidar.

[0055] In some embodiments of this disclosure, the lidar further includes a scanning mirror. The scanning mirror includes a reflector 332. The reflector 332 rotates about a pivot axis 331. The reflector 332 includes a reflective surface 333. The reflective surface 333 is used to reflect the probe light or the echo light, or to reflect both the probe light and the echo light.

[0056] The blower includes a fan blade 334. In a plane perpendicular to the rotation axis 331, the fan blade 334 has an elongated cross-section. The elongated structure includes two ends along its length. The line connecting the two ends intersects the reflective surface 333. One end is fixedly connected to the rotation axis 331. The other end of the fan blade 334...

[0057] For example, such as Figure 3 As shown, in some embodiments, transmitter 310 emits probe light. The probe light is incident on the reflective surface 333 of reflector 332 and is reflected by reflector 333. The reflected probe light is transmitted through window 320 and then exits. In some embodiments, the echo light entering the lidar through the window is incident on the reflective surface 333 of reflector 332. The reflective surface 333 of reflector 332 reflects the incident echo light, so that the echo light can be received by the receiver. Reflector 332 can reflect both probe light and echo light. In the optical path of the lidar, the probe light and echo light partially overlap or coincide; this optical path can be referred to as a coaxial optical path.

[0058] It should be noted that in some embodiments, the lidar may include a paraxial optical path. The optical paths of the probe light and the echo light do not overlap, or the probe light and the echo light do not share an optical path. The scanning mirror reflects either the probe light or the echo light.

[0059] The fan blades 334 of the blower are fixedly connected to the rotating shaft. As the reflector in the scanning mirror moves around the rotating shaft 331, the fan blades 334 also move around the rotating shaft 331. The fan blades moving around the rotating shaft 331 promote air circulation, which can improve the fogging problem on the inner surface of the window.

[0060] In some embodiments of this disclosure, the scanning mirror further includes a drive motor. The drive motor is adapted to drive the reflector to move about the axis of rotation. In some embodiments, the reflector moves about the axis of rotation under the drive of the drive motor. The drive motor can also drive fan blades to move about the axis of rotation.

[0061] The scanning mirror may include one or more of the following: a rotating mirror, a swing mirror, or a galvanometer mirror. A lidar may include one scanning mirror, or two or more scanning mirrors. When a lidar includes two or more scanning mirrors, the types of scanning mirrors may be the same or different. The movement of the reflector of the scanning mirror around its axis may be a 360° rotation, a swing within a preset range, or a vibration within a preset range.

[0062] In some embodiments of this disclosure, in a plane perpendicular to the axis of rotation, the distance between the two ends of the cross-section of the fan blade is no greater than the maximum distance between the reflecting surface and the axis of rotation. In a plane perpendicular to the axis of rotation, the maximum distance between the fan blade and the axis of rotation is no greater than the maximum distance between the reflector and the axis of rotation, such that the radius of motion of the fan blade around the axis of rotation is no greater than the radius of motion of the reflector around the axis of rotation.

[0063] like Figure 3 In some of the embodiments shown, in a plane perpendicular to the rotation axis 331, the distance L between the two ends of the fan blade 334 is not greater than the maximum distance R between the reflecting surface 332 and the rotation axis 331. L not being greater than R ensures that the rotation trajectory of the fan blade does not exceed the rotation trajectory of the reflector, which is beneficial for the miniaturization of the lidar.

[0064] In some embodiments of this disclosure, the blower includes at least two fan blades 334. The at least two fan blades 334 are distributed within a preset angle range. Providing at least two fan blades 334 effectively enhances the blower's ability to propel airflow, further improving the effect of suppressing fogging on the inner surface of the viewing window. Specifically, as... Figure 3 In some embodiments shown, the blower has four blades 334. The four blades are distributed within a preset angle range with the opening facing the viewing window 320. The preset angle range can be values ​​such as 60°, 90°, 100°, 110°, 120°, 130°, 135°, 140°, etc.

[0065] In some embodiments, the at least two fan blades are evenly distributed within a preset angle range. The included angle between adjacent fan blades is equal. Making the included angle between adjacent fan blades equal improves airflow uniformly, which is beneficial for further enhancing the effect of suppressing fogging on the inner surface of the viewing window. Specifically, as shown... Figure 3 In some embodiments shown, the four blades 334 of the blower are evenly distributed within a 90° range, and the included angle between adjacent blades 334 is 30°.

[0066] It should be noted that both the fan blades and the reflector are fixedly connected to the rotating shaft. The movement of the fan blades around the rotating shaft is consistent with the movement of the reflector around the rotating shaft. In some embodiments, the scanning mirror is a galvanometer, and the reflector vibrates back and forth around the rotating shaft, while the fan blades also vibrate back and forth around the rotating shaft; in other embodiments, the scanning mirror is a rotating mirror, and the reflector rotates unidirectionally around the rotating shaft, while the fan blades also rotate unidirectionally around the rotating shaft.

[0067] In some embodiments, the reflecting mirror in the scanning mirror reciprocates about the rotation axis. The scanning mirror can be a galvanometer or a tilting mirror. The preset range includes the window opening angle. The window opening angle is the central angle of the window relative to the rotation axis.

[0068] For example, the window opening angle is the central angle of the window relative to the rotation axis. In a plane perpendicular to the rotation axis, the window opening angle is the angle between the two edges of the rotation axis 331 and the reflective surface 333. The preset range includes the window opening angle, ensuring that the airflow generated by the fan blades distributed within the preset range can reach the entire window, further improving the effect of suppressing fogging on the inner surface of the window.

[0069] It should be noted that in some other embodiments of this disclosure, the reflector rotates unidirectionally around the axis of rotation, and the preset range is 360°. For example, the scanning mirror is a rotating mirror, and the reflector rotates unidirectionally around the axis of rotation. At least two fan blades are distributed within a circle around the axis of rotation. In the scanning scheme of the rotating mirror, distributing the fan blades around the axis of rotation once effectively ensures the stability and reliability of the reflector's rotation.

[0070] Semi-solid-state LiDAR, which includes a scanning mirror, incorporates fan blades on the scanner. These blades, driven by a motor, rotate around an axis, thus fanning the inner surface of the viewing window. The fan blades can reuse the scanning mirror's drive motor, eliminating the need for additional drive components. This facilitates miniaturization of the LiDAR and reduces its cost.

[0071] It should be understood that the division of modules and units in the above system is only a logical functional division. In actual implementation, there may be other division methods. In actual implementation, they may be fully or partially integrated into a single physical entity, or they may be physically separated. Furthermore, the modules and units in the device can be implemented by a processor calling software; for example, the device includes a processor connected to memory, which stores instructions. The processor calls the instructions stored in memory to implement any of the above methods or to implement the functions of each module and unit of the device. The processor may be a general-purpose processor, such as a central processing unit (CPU) or a microprocessor, and the memory may be internal or external to the system. Alternatively, the modules and units in the device can be implemented in the form of hardware circuits. The functionality of some or all modules can be achieved through the design of these hardware circuits, which can be understood as one or more processors. For example, in one implementation, the hardware circuit is an application-specific integrated circuit (ASIC), and the functionality of some or all of the above modules is achieved through the design of the logical relationships between the components within the circuit. In another implementation, the hardware circuit can be implemented using a programmable logic device (PLD), which can include a large number of logic gates. The logical relationships between these logic gates are configured through configuration files, thereby achieving the functionality of some or all of the above modules. All modules of the above system can be implemented entirely through processor-invoked programs, entirely through hardware circuits, or partially through processor-invoked programs with the remaining parts implemented through hardware circuits.

[0072] In summary, the blower is suitable for blowing air onto the inner surface of the window to eliminate fog. Blowing air onto the inner surface of the window effectively removes fog from inside the window, thus effectively improving the problem of fogging inside the lidar window.

[0073] While the above disclosure is provided, it is not limited thereto. Any person skilled in the art may make various alterations and modifications without departing from the spirit and scope of this disclosure; therefore, the scope of protection of this disclosure shall be determined by the scope defined in the claims.

Claims

1. A lidar, comprising: include: A transmitter adapted to emit a probe light; Receiver, the receiver being adapted to receive the echo light generated after the probe light is reflected by an object; A window, the window being adapted to allow the probe light to exit into the external space of the lidar, the window being further adapted to allow the echo light to enter into the internal space of the lidar, the window having an inner surface facing the internal space of the lidar; A blower adapted to blow air onto the inner surface of the window.

2. The lidar of claim 1, wherein, The blower is a fan.

3. The lidar of claim 2, wherein, The fan outlet is provided with multiple grilles, which are arranged in parallel.

4. The lidar of claim 2, wherein, The diameter of the fan is less than 1 cm.

5. The lidar of any one of claims 1-4, wherein, The lidar is a solid-state lidar.

6. The lidar of claim 1, wherein, Also includes: A scanning mirror, the scanning mirror including a reflector that rotates about a rotation axis, the reflector including a reflective surface for reflecting at least one of the probe light and the echo light; The blower includes a fan blade, one end of which is fixedly connected to the rotating shaft, and the line connecting the one end to the other end of the fan blade intersects with the reflective surface.

7. The lidar of claim 6, wherein, In a plane perpendicular to the axis of rotation, the distance between one end of the fan blade and the other end is no greater than the maximum distance between the reflective surface and the axis of rotation.

8. The lidar as described in claim 6, characterized in that, The blower includes at least two fan blades; The at least two fan blades are distributed within a preset angle range.

9. The lidar of claim 8, wherein, The at least two fan blades are evenly distributed within a preset angle range.

10. The lidar of claim 8, wherein, The included angle between adjacent blades is equal.

11. The lidar of claim 8, wherein, In the scanning mirror, the reflecting mirror rotates unidirectionally around the rotating axis; The preset angle range is 360°.

12. The lidar of claim 8, wherein, In the scanning mirror, the reflecting mirror reciprocates around the rotating axis; The preset angle range includes: the window opening angle, which is the central angle of the window relative to the rotation axis.

13. The lidar of claim 6, wherein, The scanning mirror further includes a drive motor adapted to drive the reflector to move around the rotating axis.

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