Lidar module

Abstract

A laser radar module includes a laser emitter, a rotatable support, a first reflecting surface, a second reflecting surface, and a light sensor. The laser emitter is configured to emit a laser beam. The rotatable support has opposite first and second sides. The first reflecting surface is disposed on the first side of the rotatable support and is configured to reflect the laser beam to an environment. The second reflecting surface is disposed on the second side of the rotatable support and is configured to reflect the laser beam reflected by an object in the environment. The light sensor is disposed in a path of the laser beam reflected by the second reflecting surface and is configured to sense the laser beam. The rotatable support is adapted to rotate so that the laser beam reflected by the first reflecting surface scans the environment in different directions and so that the second reflecting surface receives the laser beam from the environment in different directions.

Description

Technical Field

[0001] This invention relates to an optical module, and more particularly to a lidar module. Background Technology

[0002] LiDAR is a technology that uses laser pulses to measure the distance between an object and a sensor. It works by emitting a laser, measuring the time it takes for the laser pulse to reflect back from the target, and then calculating the distance using the speed of light. This data is then converted into a 3D point cloud map, which is used to further generate the object's shape and spatial distribution.

[0003] The main components of a lidar system include a laser transmitter, a receiver, an optical scanning system, and a processing unit. The laser transmitter generates laser pulses, the receiver receives the reflected laser signals, the optical scanning system (usually a rotating mechanism or a multi-line laser system) assists in scanning the environment, and the processing unit converts the measured data into a useful 3D image or model.

[0004] Mechanical rotating lidar is a classic and widely used lidar structure. It operates like a rotating laser light source, constantly scanning the surrounding environment and capturing details in three-dimensional space.

[0005] Mechanical rotating lidar achieves 360-degree omnidirectional scanning through an internal rotating structure. The laser emitter emits a laser pulse, which is guided in a specific direction by a reflector (usually a rotating reflector). After the scan is completed, the receiver captures the laser signal reflected back from the target object.

[0006] The key component for rotation is typically a high-speed rotating mirror or the entire laser transmitting and receiving module. As the rotation angle changes, the laser beam gradually sweeps across the entire environment, eventually constructing a complete 360-degree point cloud image.

[0007] However, rotating the entire laser transmitter and receiver module can overload the motor and consume excessive energy. Using a rotating reflector, current technology places the laser transmitter and sensor on the same side of the rotating reflector. This results in the laser emission and reception paths reversing when the reflector rotates 180 degrees, leading to positional errors in environmental detection. To solve this problem, galvanometers can be placed along the optical path, or algorithms can be used for correction, but these methods increase the cost of the lidar system. Summary of the Invention

[0008] This invention relates to a lidar module that combines the advantages of low power consumption, high accuracy, and low cost.

[0009] An embodiment of the present invention provides a lidar module, including a laser emitter, a rotatable support, a first reflective surface, a second reflective surface, and a light sensor. The laser emitter emits a laser beam, and the rotatable support has a first side and a second side facing each other. The first reflective surface is disposed on the first side of the rotatable support, positioned in the path of the laser beam, and used to reflect the laser beam to the outside. The second reflective surface is disposed on the second side of the rotatable support, positioned in the path of the laser beam reflected by an external object, and used to reflect the laser beam reflected by the object. The light sensor is disposed in the path of the laser beam reflected by the second reflective surface and used to sense the laser beam. The rotatable support is adapted to rotate, causing the first and second reflective surfaces to rotate, so that the laser beam reflected by the first reflective surface scans the outside in different directions, and the second reflective surface receives laser beams from different directions from the outside.

[0010] In the lidar module of this invention, a first reflective surface is disposed on a first side of a rotatable support and is used to reflect a laser beam to the outside world. A second reflective surface is disposed on a second side of the rotatable support and is used to reflect laser beams reflected by external objects. The rotatable support is adapted to rotate, thereby rotating the first and second reflective surfaces, so that the laser beams reflected by the first reflective surface scan the outside world in different directions, and the second reflective surface receives laser beams from different directions from the outside world. With this configuration, some components (i.e., the rotatable support) in the lidar module can rotate without reversing the optical path of the laser beam emitted to the outside world and the optical path of the laser beam received from the outside world during rotation. Therefore, the lidar module of this invention has the advantages of lower energy consumption, higher accuracy, and lower cost. Attached Figure Description

[0011] Figure 1A This is a three-dimensional schematic diagram of a lidar module according to an embodiment of the present invention;

[0012] Figure 1B for Figure 1A A side view of the lidar module;

[0013] Figure 1C for Figure 1A A stereoscopic diagram of the lidar module from another perspective;

[0014] Figure 1D and Figure 1E for Figure 1A A partial stereoscopic diagram of the lidar module from two different perspectives;

[0015] Figure 2 for Figure 1B A three-dimensional schematic diagram of the diffuser sheet in the image;

[0016] Figure 3A Show Figure 1B The diffuser in the laser beam disperses the laser beam into a straight line of light sources;

[0017] Figure 3B Show Figure 1B The diffuser in the laser beam disperses the laser beam into a surface-shaped light source;

[0018] Figure 4 This is a partial three-dimensional schematic diagram of a lidar module according to another embodiment of the present invention. Detailed Implementation

[0019] Reference will now be made in detail to exemplary embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same element references are used in the drawings and description to denote the same or similar parts.

[0020] Figure 1A This is a three-dimensional schematic diagram of a lidar module according to an embodiment of the present invention. Figure 1B for Figure 1A A side view diagram of the lidar module. Figure 1C for Figure 1A A stereoscopic diagram of the lidar module from another perspective, and Figure 1D and Figure 1E for Figure 1A The diagram shows a partial 3D view of the lidar module from two different perspectives. Please refer to... Figures 1A to 1E The lidar module 100 of this embodiment includes a laser emitter 110, a rotatable support 120, a first reflective surface 130, a second reflective surface 140, and a light sensor 150. The laser emitter 110 emits a laser beam 112. The rotatable support 120 has opposing first sides S1 and S2. The first reflective surface 130 is disposed on the first side S1 of the rotatable support 120, positioned in the path of the laser beam 112, and used to reflect the laser beam 112 to the outside. The second reflective surface 140 is disposed on the second side S2 of the rotatable support 120, positioned in the path of the laser beam 112 reflected by an external object 50, and used to reflect the laser beam 112 reflected by the object 50. The light sensor 150 is positioned in the path of the laser beam 112 reflected by the second reflective surface 140, and used to sense the laser beam 112. The rotatable support 120 is adapted to rotate to drive the first reflective surface 130 and the second reflective surface 140 to rotate, so that the laser beam 112 reflected by the first reflective surface 130 scans the outside world in different directions, and the second reflective surface 140 receives the laser beam 112 from the outside world from different directions.

[0021] In this embodiment, the lidar module 100 forms a time-of-flight sensor. By calculating the time difference or phase difference between the laser beam 112 emitted by the laser emitter 110 and the laser beam 112 received by the optical sensor 150, the distance of the surrounding objects 50 can be calculated. When the laser beam 112 scans the outside world in different directions, a point cloud map containing the position and distance of each object in the external environment can be obtained to achieve the sensing of the surrounding environment.

[0022] In the lidar module 100 of this embodiment, a first reflective surface 130 is disposed on the first side S1 of the rotatable support 120 and is used to reflect the laser beam 112 to the outside. A second reflective surface 140 is disposed on the second side S2 of the rotatable support 120 and is used to reflect the laser beam 112 reflected by the external object 50. The rotatable support 120 is adapted to rotate, thereby causing the first reflective surface 130 and the second reflective surface 140 to rotate, so that the laser beam 112 reflected by the first reflective surface 130 scans the outside in different directions, and the second reflective surface 140 receives laser beams 112 from different directions. With this configuration, some components (i.e., the rotatable support 120) in the lidar module 100 can be rotated, and during the rotation, the optical path of the laser beam 112 emitted to the outside and the optical path of the laser beam 112 received from the outside will not be reversed. This eliminates the need for additional costs associated with using galvanometers configured on the optical path or using algorithms for correction. Therefore, the lidar module 100 of this embodiment has the advantages of low power consumption, high accuracy, and low cost. In this embodiment, the first reflecting surface 130 can be the reflecting surface of a mirror, and the second reflecting surface 140 can be the reflecting surface of another mirror.

[0023] Figure 2 for Figure 1B A three-dimensional schematic diagram of the diffuser plate in the diagram. Figure 3A Show Figure 1B The diffuser in the middle disperses the laser beam into a straight line of light sources, while Figure 3B Show Figure 1B The diffuser in the laser beam disperses the laser beam into a surface-shaped light source. Please refer to... Figures 1A to 1E , Figure 2 , Figure 3A and Figure 3B In this embodiment, the lidar module 100 includes a diffuser 160 disposed in the path of the laser beam 112, located between the laser emitter 110 and the first reflective surface 130, and used to disperse the laser beam 112 into a surface light source 112 (e.g., Figure 3B ) or a vertical light source 112' (e.g. Figure 3AIn this embodiment, the laser emitter 110 is, for example, a laser diode, and the light sensor 150 is, for example, an image sensor, which may have a plurality of pixels arranged in a one-dimensional or two-dimensional array.

[0024] In this embodiment, the lidar module 100 includes a plurality of magnets 170, a substrate 180, and a plurality of coils 190. The magnets 170 are arranged around a rotatable support 120. The substrate 180 has an opening 182 for accommodating one end of the rotatable support 120 and the magnets 170. The coils 190 are disposed at the edge of the opening 182, and are adapted to be energized to generate a magnetic force on the magnets 170, thereby causing the rotatable support 120 to rotate.

[0025] In this embodiment, the first reflective surface 130 and the second reflective surface 140 are tilted relative to the substrate 180 in two opposite directions at an angle greater than 35 degrees and less than 55 degrees. For example, in one embodiment, the first reflective surface 130 and the second reflective surface 140 are tilted relative to the substrate 180 in two opposite directions at 45 degrees. In this embodiment, the included angle θ1 between the first reflective surface 130 and the second reflective surface 140 is greater than 0 degrees and less than 180 degrees. In one embodiment, the included angle θ1 between the first reflective surface 130 and the second reflective surface 140 is greater than 70 degrees and less than 110 degrees. For example, when the first reflective surface 130 and the second reflective surface 140 are tilted relative to the substrate 180 in two opposite directions at 45 degrees, the included angle θ1 between the first reflective surface 130 and the second reflective surface 140 is equal to 90 degrees.

[0026] In this embodiment, the lidar module 100 includes a base 270, wherein a light sensor 150 is disposed on the base 270 and located between the base 270 and a second reflective surface 140. The second reflective surface 140 is located between the light sensor 150 and a first reflective surface 130, and the first reflective surface 130 is located between the second reflective surface 140 and a laser emitter 110. Furthermore, the rotatable support 120 can rotate 360 ​​degrees around axis A1, wherein the extension direction of axis A1 can be from the light sensor 150 towards the laser emitter 110.

[0027] In this embodiment, the lidar module 100 includes a first lens 250 and a second lens 260. The first lens 250 is disposed in the path of the laser beam 112 and located between the laser emitter 110 and the first reflective surface 130 to collimate the laser beam 112. The second lens 260 is disposed in the path of the laser beam 112 and located between the second reflective surface 140 and the photosensor 150 to focus the laser beam 112 from the external object 50 onto the photosensor 150.

[0028] In this embodiment, the lidar module includes a top cover 210, a wireless charging coil 220, and a wireless induction coil 230. The laser emitter 110 is disposed on the top cover 210, and the wireless charging coil 220 is disposed on the substrate 180. The wireless induction coil 230 is disposed on the top cover 210, opposite to the wireless charging coil 220, and electrically connected to the laser emitter 110. The wireless charging coil 220 generates a magnetic field for charging, and the wireless induction coil 230 generates an induced current due to the magnetic field to power the laser emitter 110. Using wireless charging to power the laser emitter 110 avoids the conductive lines blocking the laser beam 112's optical path.

[0029] In this embodiment, the lidar module 100 may include an annular side cover 280, connecting the top cover 210 and the base 270, and surrounding the laser emitter 110, the rotatable support 120, the first reflective surface 130, the second reflective surface 140, and the light sensor 150. The annular side cover 280 may be made of a material that can be penetrated by the laser beam 112. In one embodiment, the wavelength of the laser beam 112 is, for example, 905 nanometers or 940 nanometers.

[0030] Figure 4 This is a partial perspective view of a lidar module according to another embodiment of the present invention. Please refer to... Figure 4 The lidar module 100a in this embodiment is similar to Figure 1A The lidar module 100a of this embodiment includes a transparent conductive post 240 connecting the edge of the substrate 180 and the top cover 210, and electrically connected to the laser emitter 110 to provide power from the substrate 180 to the laser emitter 110. When the rotatable support 120 rotates, causing the laser beam 112 to scan the surrounding environment, the laser beam 112 can penetrate the transparent conductive post 240 when scanning its location without causing obstruction. In one embodiment, the transparent conductive post 240 is made of, for example, indium tin oxide, but the invention is not limited thereto.

[0031] In the lidar module of this invention, a first reflective surface is disposed on a first side of a rotatable support and is used to reflect a laser beam to the outside world. A second reflective surface is disposed on a second side of the rotatable support and is used to reflect laser beams reflected by external objects. The rotatable support is adapted to rotate, thereby rotating the first and second reflective surfaces, so that the laser beams reflected by the first reflective surface scan the outside world in different directions, and the second reflective surface receives laser beams from different directions from the outside world. With this configuration, some components (i.e., the rotatable support) in the lidar module can rotate without reversing the optical path of the laser beam emitted to the outside world and the optical path of the laser beam received from the outside world during rotation. Therefore, the lidar module of this invention has the advantages of lower energy consumption, higher accuracy, and lower cost.

[0032] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A lidar module, characterized in that, include: A laser emitter, used to emit a laser beam; A rotatable support having opposing first and second sides; A first reflecting surface is disposed on the first side of the rotatable support, positioned in the path of the laser beam, and used to reflect the laser beam to the outside. A second reflective surface is disposed on the second side of the rotatable support, positioned in the path of the laser beam reflected by the external object, and used to reflect the laser beam reflected by the object. as well as A light sensor is positioned along the path of the laser beam reflected by the second reflective surface and is used to sense the laser beam. The rotatable support is adapted to rotate to drive the first reflective surface and the second reflective surface to rotate, so that the laser beam reflected by the first reflective surface scans the outside world in different directions, and the second reflective surface receives the laser beam from the outside world in different directions.

2. The lidar module according to claim 1, characterized in that, It includes a diffuser plate disposed in the path of the laser beam, located between the laser emitter and the first reflective surface, and is used to disperse the laser beam into a surface light source or a linear light source.

3. The lidar module according to claim 1, characterized in that, include: Multiple magnets are arranged around the rotatable support; A substrate having an opening for accommodating one end of the rotatable support and the plurality of magnets; as well as Multiple coils are disposed at the edge of the opening, wherein the coils are adapted to be energized to generate magnetic force on the multiple magnets, thereby causing the rotatable support to rotate.

4. The lidar module according to claim 3, characterized in that, include: A top cover, wherein the laser emitter is disposed on the top cover; A wireless charging coil is disposed on the substrate; as well as A wireless induction coil is disposed on the upper cover, positioned opposite the wireless charging coil, and electrically connected to the laser transmitter, wherein the wireless charging coil generates a magnetic field for charging, and the wireless induction coil generates an induced current due to the magnetic field to provide power to the laser transmitter.

5. The lidar module according to claim 3, characterized in that, Also includes: A top cover, wherein the laser emitter is disposed on the top cover; as well as A transparent conductive pillar connects the edge of the substrate and the top cover, and is electrically connected to the laser emitter to provide power from the substrate to the laser emitter.

6. The lidar module according to claim 3, characterized in that, The first reflective surface and the second reflective surface are tilted relative to the substrate in two opposite directions at an angle greater than 35 degrees and less than 55 degrees.

7. The lidar module according to claim 1, characterized in that, include: The first lens is positioned on the path of the laser beam and located between the laser emitter and the first reflective surface; as well as The second lens is positioned on the path of the laser beam and between the second reflective surface and the light sensor.

8. The lidar module according to claim 1, characterized in that, The angle between the first reflective surface and the second reflective surface is greater than 0 degrees and less than 180 degrees.

9. The lidar module according to claim 8, characterized in that, The angle between the first reflective surface and the second reflective surface is greater than 70 degrees and less than 110 degrees.

10. The lidar module according to claim 1, characterized in that, The device includes a base, wherein the light sensor is disposed on the base and located between the base and a second reflective surface, the second reflective surface is located between the light sensor and a first reflective surface, and the first reflective surface is located between the second reflective surface and the laser emitter.

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