Patent Publication Number: US-2021190918-A1

Title: Lidar, laser emitter, laser emitter emitting board assembly, and method for manufacturing laser emitter

Description:
BACKGROUND 
     Technical Field 
     The present disclosure relates to the technical field of laser detection, and in particular, to a lidar, a laser emitter, a laser emitter emitting board assembly, and a method for manufacturing the laser emitter. 
     Related Art 
     As an important part of an intelligent vehicle-environment sensing hardware system, a lidar undertakes important tasks such as roadside detection, obstacle recognition, and real-time localization and mapping (SLAM) in automatic driving. A lidar system includes a laser emitting system and a receiving system. The laser emitting system generates and emits light pulses, which impinge on an object and are reflected back and are finally received by a receiver. The receiver accurately measures propagation duration between emission and reflection of light pulses. Since the light pulse propagates at the speed of light, the receiver receives a previous reflected pulse before a next pulse is emitted. Since the speed of light is known, the propagation time can be converted into a measured distance. The lidar can accurately measure a position (a distance and an angle), a motion state (a speed, vibration, and a posture) and a shape of a target, to detect, identify, distinguish and track the target. Due to a fast measurement speed, high accuracy and a capability of long-distance measurement, the lidar is widely used in intelligent vehicles. 
     An existing mechanical multi-beam lidar generates a plurality of laser beams by a plurality of laser sources which multiplex the same lens or the same set of lenses, where the plurality of laser light sources are arranged at different heights on a focal plane of the lens. In this way, different orientations in the vertical direction are generated, thus forming a plurality of laser beams. In order to increase a number of laser beams of the lidar, laser emitters are arranged at different heights on an image surface of the emitting lens. A smaller height difference leads to more laser beams and a higher beam angle resolution. A larger number of columns leads to greater difficulty in production, assembly, and adjustment, a more complex process, and lower production efficiency. Space utilization in the system is low, the focal plane is very crowed, and a large amount of heat is generated, which is very difficult to conduct. However, at other places, there are few devices and little heat is generated Laser emitter arrangement relates to a whole layout of a laser emitting apparatus. A conventional semiconductor laser pulse diode has a very small light-emitting area. However, in fact, laser emitters cannot be very close to each other due to chip encapsulation and a size of a drive circuit. In addition, most lidars transmit power through a wireless power transmission apparatus, and specific arrangement of the wireless power transmission apparatus may affect overall performance of the lidar. Therefore, it is necessary to provide a new lidar that is less difficult to assemble and adjust and for which heat dissipation of a laser emitter and reduction of an overall size are also considered. 
     SUMMARY 
     To resolve at least one of the above technical problems, the present disclosure discloses a lidar. The lidar specifically includes the following aspects. 
     According to a first aspect of the present disclosure, a lidar is provided. The lidar includes a rotor, a laser emitting system, and a receiving system. The rotor has an emitting chamber and a receiving chamber that are separated from each other. The laser emitting system is disposed in the emitting chamber, and the receiving system is disposed in the receiving chamber. The laser emitting system includes a laser emitter bracket configured to fix at least one laser emitter emitting board. 
     Further, the laser emitter emitting board is fixed in a direction perpendicular to a first plane by the laser emitter bracket. Alternatively, the laser emitter emitting board is fixed in a direction parallel to the first plane by the laser emitter bracket. The first plane is a plane defined by a rotation direction of the rotor of the lidar. In an optional example, the lidar is placed horizontally, and the first plane is a plane parallel to the horizontal plane. Certainly, the horizontal plane is not a limitation on a position of the first plane in this specification. 
     According to a second aspect of the present disclosure, a lidar is provided. The lidar a rotor, a laser emitting system, and a receiving system. The rotor has an emitting chamber and a receiving chamber that are separated from each other. The laser emitting system is disposed in the emitting chamber, and the receiving system is disposed in the receiving chamber. The rotor further includes an outer cylinder and an inner cylinder. A mounting structure for an emitting lens set and a receiving lens set is disposed on a wall of the outer cylinder. 
     According to a third aspect of the present disclosure, a lidar is provided. The lidar includes a rotor, a laser emitting system, and a receiving system. The rotor has an emitting chamber and a receiving chamber that are separated from each other. The laser emitting system is disposed in the emitting chamber, and the receiving system is disposed in the receiving chamber. The laser emitting system includes a first mirror set and an emitting lens set, where the first mirror set is configured to change a path of an exit beam of the laser emitter, so that the laser beam is incident on the emitting lens set, and the emitting lens set is configured to emit detection light; and/or the receiving system includes a receiving lens set, a second mirror set, and a receiving apparatus, where the receiving lens set is configured to converge light reflected from a to-be-detected object, and the second mirror set is configured to change a path of a beam, so that the reflected light is incident on the receiving apparatus. 
     According to a fourth aspect of the present disclosure, a lidar is provided. The lidar includes: a rotor, a laser emitting system, and a receiving system, where the rotor has an emitting chamber and a receiving chamber that are separated from each other, the laser emitting system is disposed in the emitting chamber, and the receiving system is disposed in the receiving chamber; a wireless power transmission apparatus including a wireless power emitting assembly and a wireless power receiving assembly, where the wireless power emitting assembly is separated from the wireless power receiving assembly, the wireless power emitting assembly includes a transmitting coil and a transmitting circuit board, where the transmitting coil is connected to the transmitting circuit board; and the wireless power receiving assembly includes a receiving coil and a magnetic isolation element, where a first surface of the receiving coil is separated from a second surface of the transmitting coil, and the magnetic isolation element is disposed on a side of the receiving coil away from the transmitting coil. In a specific example, the first surface of the receiving coil and the second surface of the transmitting coil are planes of the receiving coil and the transmitting coil close to each other. 
     The present disclosure relates to a lidar. The lidar includes: a rotor, where the rotor has an emitting chamber and a receiving chamber that are separated from each other, where the emitting chamber and the receiving chamber are asymmetrically distributed; a laser emitting system disposed in the emitting chamber and including a laser emitter bracket and at least one laser emitter emitting board fixed to the laser emitter bracket; and a receiving system disposed in the receiving chamber. 
     According to an aspect of the present disclosure, the laser emitter emitting board is fixed in a direction perpendicular to a first plane by the laser emitter bracket. Alternatively, the laser emitter emitting board is fixed in a direction parallel to the first plane by the laser emitter bracket. 
     According to an aspect of the present disclosure, the laser emitter bracket has a comb structure with at least one slot, where the laser emitter emitting board is fixed to the slot. 
     According to an aspect of the present disclosure, the laser emitter emitting board is at a preset angle to a horizontal plane; and at least one laser emitter is disposed on the laser emitter emitting board, where a light-emitting surface of the laser emitter is located on a focal plane of an optical exit system of the lidar. 
     According to an aspect of the present disclosure, when laser emitter emitting boards are fixed to the laser emitter bracket in the direction perpendicular to the first plane, the laser emitter emitting boards are disposed at intervals in the direction perpendicular to the first plane. 
     According to an aspect of the present disclosure, when laser emitter emitting boards are fixed to the laser emitter bracket in the direction parallel to the first plane, the laser emitter emitting boards are disposed at intervals in the direction parallel to the first plane. 
     According to an aspect of the present disclosure, the laser emitting system includes a laser emitter disposed on the laser emitter emitting board, where the laser emitter includes: a base having a positioning portion thereon; a laser emitter chip disposed on the base and having a light-emitting surface; a laser beam shaping element positioned opposite to the light-emitting surface of the laser emitter chip through the positioning portion. 
     According to an aspect of the present disclosure, the positioning portion includes one or more of a V-shaped groove, a U-shaped groove, and a step, and the laser beam shaping element includes one or more of an optical fiber, a cylindrical lens, a D lens, or an aspherical lens. 
     According to an aspect of the present disclosure, the laser emitter chip is of an edge-emitting type, the light-emitting surface has a slow axis direction and a fast axis direction, where the slow axis direction is parallel to a direction in which the laser beam shaping element extends, and the laser beam shaping element is a fast axis compression element configured to compress an angle of divergence of a laser emitted from the light-emitting surface in the fast axis direction. 
     According to an aspect of the present disclosure, the base is a silicon base, the positioning portion is formed on the silicon base through an etching process, and the laser emitter further includes an electrode disposed on the base, where the electrode is configured to supply power to the laser emitter chip and includes a positive electrode and a negative electrode separated by a partition. 
     According to an aspect of the present disclosure, the positive electrode and the negative electrode are both disposed on the same surface of the base as the laser emitter chip and on a side surface of the base perpendicular to the light-emitting surface. 
     According to an aspect of the present disclosure, the positive electrode and the negative electrode are both disposed on the same surface of the base as the laser emitter chip and on an end surface of the base parallel to the light-emitting surface. 
     According to an aspect of the present disclosure, the laser emitter emitting board includes a circuit board and a plurality of laser emitters disposed on the circuit board, where light-emitting surfaces of laser emitter chips of the laser emitters are oriented in the same direction. 
     According to an aspect of the present disclosure, the plurality of laser emitters are soldered on the circuit board, where a slow axis direction of the light-emitting surfaces of the plurality of laser emitters is perpendicular to the circuit board. 
     According to an aspect of the present disclosure, the plurality of laser emitters are soldered on the circuit board, where a slow axis direction of the light-emitting surfaces of the plurality of laser emitters is parallel to the circuit board, and the light-emitting surfaces of the laser emitter chips in the plurality of laser emitters on the circuit board are staggered with respect to each other in a fast axis direction. 
     According to an aspect of the present disclosure, the laser emitter bracket is a comb structure with a plurality of vertical slots, where laser emitter emitting boards are respectively disposed in the plurality of slots, where light-emitting surfaces of laser emitter chips of the laser emitter emitting boards in the plurality of slots are staggered with respect to each other in a fast axis direction. 
     According to an aspect of the present disclosure, a center of the laser beam shaping element is at the same height as a center of the light-emitting surface of the laser emitter chip. 
     The present invention further relates to a lidar. The lidar includes: a rotor, where the rotor has an emitting chamber and a receiving chamber that are separated from each other, where the emitting chamber and the receiving chamber are asymmetrically distributed; a laser emitting system disposed in the emitting chamber; and a receiving system disposed in the receiving chamber, where the rotor further includes an outer cylinder and an inner cylinder, and a mounting structure for an emitting lens set and a receiving lens set is disposed on a wall of the outer cylinder. 
     According to an aspect of the present disclosure, an accommodation cavity is formed between the outer cylinder and the inner cylinder, where a separator is disposed in the accommodation cavity, where one end of the separator is connected to the outer cylinder, the other end of the separator is connected to the inner cylinder, and the separator divides the accommodation cavity into the emitting chamber and the receiving chamber. 
     According to an aspect of the present disclosure, a third counterweight structure is provided on the rotor, where the third counterweight structure is disposed on both sides of the mounting structure, and the third counterweight structure includes a plurality of first grooves, where a connecting rib is formed between two adjacent first grooves. 
     According to an aspect of the present disclosure, the wall of the outer cylinder includes a movable wall and a fixed wall, where the movable wall is detachably connected to the fixed wall, and at least one first counterweight block is disposed on the movable wall. 
     According to an aspect of the present disclosure, the lidar further includes a baseplate, where the baseplate is disposed at a bottom of the rotor, and at least one second counterweight block is disposed on the baseplate. 
     According to an aspect of the present disclosure, where the laser emitting system includes a laser emitter. The laser emitter includes: a base having a positioning portion thereon; a laser emitter chip disposed on the base and having a light-emitting surface; a laser beam shaping element positioned opposite to the light-emitting surface of the laser emitter chip through the positioning portion. 
     According to an aspect of the present disclosure, the positioning portion includes one or more of a V-shaped groove, a U-shaped groove, and a step, and the laser beam shaping element includes one or more of an optical fiber, a cylindrical lens, a D lens, or an aspherical lens. 
     According to an aspect of the present disclosure, the laser emitter chip is of an edge-emitting type, the light-emitting surface has a slow axis direction and a fast axis direction, where the slow axis direction is parallel to a direction in which the laser beam shaping element extends, and the laser beam shaping element is a fast axis compression element configured to compress an angle of divergence of a laser emitted from the light-emitting surface in the fast axis direction. 
     According to an aspect of the present disclosure, the base is a silicon base, the positioning portion is formed on the silicon base through an etching process, and the laser emitter further includes an electrode disposed on the base, where the electrode is configured to supply power to the laser emitter chip and includes a positive electrode and a negative electrode separated by a partition. 
     According to an aspect of the present disclosure, the positive electrode and the negative electrode are both disposed on the same surface of the base as the laser emitter chip and on a side surface of the base perpendicular to the light-emitting surface. 
     According to an aspect of the present disclosure, the positive electrode and the negative electrode are both disposed on the same surface of the base as the laser emitter chip and on an end surface of the base parallel to the light-emitting surface. 
     According to an aspect of the present disclosure, the laser emitting system includes a laser emitter bracket and at least one laser emitter emitting board fixed to the laser emitter bracket, where the laser emitter emitting board includes a circuit board and a plurality of laser emitters disposed on the circuit board, where light-emitting surfaces of laser emitter chips of the laser emitters are oriented in the same direction. 
     According to an aspect of the present disclosure, the plurality of laser emitters are soldered on the circuit board, where a slow axis direction of the light-emitting surfaces of the plurality of laser emitters is perpendicular to the circuit board. 
     According to an aspect of the present disclosure, the plurality of laser emitters are soldered on the circuit board, where a slow axis direction of the light-emitting surfaces of the plurality of laser emitters is parallel to the circuit board, and the light-emitting surfaces of the laser emitter chips in the plurality of laser emitters on the circuit board are staggered with respect to each other in a fast axis direction. 
     According to an aspect of the present disclosure, the laser emitter bracket is a comb structure with a plurality of vertical slots, where laser emitter emitting boards are respectively disposed in the plurality of slots, where light-emitting surfaces of laser emitter chips of the laser emitter emitting boards in the plurality of slots are staggered with respect to each other in a fast axis direction. 
     According to an aspect of the present disclosure, a center of the laser beam shaping element is at the same height as a center of the light-emitting surface of the laser emitter chip. 
     The present disclosure relates to a lidar. The lidar includes: a rotor, where the rotor has an emitting chamber and a receiving chamber that are separated from each other, where the emitting chamber and the receiving chamber are asymmetrically distributed; a laser emitting system disposed in the emitting chamber; and a receiving system disposed in the receiving chamber, where the laser emitting system includes a laser emitter, a first mirror set, and an emitting lens set, where the first mirror set is configured to change a path of a laser beam of the laser emitter, so that the laser beam is incident on the emitting lens set, and the emitting lens set is configured to emit detection light; and/or the receiving system includes a receiving lens set, a second mirror set, and a receiving apparatus, where the receiving lens set is configured to converge light reflected from a to-be-detected object, and the second mirror set is configured to change a path of the beam, so that the reflected light is incident on the receiving apparatus. 
     According to an aspect of the present disclosure, the lidar further includes a light isolation sheet and a light isolation frame, where the light isolation sheet is disposed between the emitting lens set and the receiving lens set, one end of the light isolation sheet is disposed between a second mirror and a fourth mirror, and the other end of the light isolation sheet is attached to the light isolation frame. 
     According to an aspect of the present disclosure, the lidar further includes a fixed block, where a lapping strip is disposed on the fixed block, where one end of the lapping strip is lapped on an inner cylinder, and the other end of the lapping strip is lapped on an outer cylinder. 
     According to an aspect of the present disclosure, the receiving apparatus includes a light filter, a receiving device, a receiving circuit bracket, and a plurality of receiving circuit boards, where the receiving device and the receiving circuit boards are mounted to the receiving circuit bracket, and the light filter is configured to filter stray light. 
     According to an aspect of the present disclosure, the receiving device includes a substrate and at least one APD detector, where the substrate is fixed to the receiving circuit bracket, and the APD detector is disposed on a side surface of the substrate. 
     According to an aspect of the present disclosure, the lidar further includes a pedestal, an enclosure, and a top cap, one end of the enclosure is mated with the pedestal, the other end of the enclosure is mated with the top cap, and the pedestal, the enclosure, and the top cap are sequentially connected to form an enclosed cavity, where enclosed cavity is configured to accommodate the rotor, the laser emitting system, and the receiving system. 
     According to an aspect of the present disclosure, the receiving device includes a plurality of APD detectors, where the APD detectors are arranged as linear-array APD detectors or planar-array APD detectors. 
     According to an aspect of the present disclosure, the laser emitter includes: a base having a positioning portion thereon; a laser emitter chip disposed on the base and having a light-emitting surface; a laser beam shaping element positioned opposite to the light-emitting surface of the laser emitter chip through the positioning portion. 
     According to an aspect of the present disclosure, the positioning portion includes one or more of a V-shaped groove, a U-shaped groove, and a step, and the laser beam shaping element includes one or more of an optical fiber, a cylindrical lens, a D lens, or an aspherical lens. 
     According to an aspect of the present disclosure, the laser emitter chip is of an edge-emitting type, the light-emitting surface has a slow axis direction and a fast axis direction, where the slow axis direction is parallel to a direction in which the laser beam shaping element extends, and the laser beam shaping element is a fast axis compression element configured to compress an angle of divergence of a laser emitted from the light-emitting surface in the fast axis direction. 
     According to an aspect of the present disclosure, the base is a silicon base, the positioning portion is formed on the silicon base through an etching process, and the laser emitter further includes an electrode disposed on the base, where the electrode is configured to supply power to the laser emitter chip and includes a positive electrode and a negative electrode separated by a partition. 
     According to an aspect of the present disclosure, the positive electrode and the negative electrode are both disposed on the same surface of the base as the laser emitter chip and on a side surface of the base perpendicular to the light-emitting surface. 
     According to an aspect of the present disclosure, the positive electrode and the negative electrode are both disposed on the same surface of the base as the laser emitter chip and on an end surface of the base parallel to the light-emitting surface. 
     According to an aspect of the present disclosure, the laser emitting system includes a laser emitter bracket and at least one laser emitter emitting board fixed to the laser emitter bracket, where the laser emitter emitting board includes a circuit board and a plurality of laser emitters disposed on the circuit board, where light-emitting surfaces of laser emitter chips of the laser emitters are oriented in the same direction. 
     According to an aspect of the present disclosure, the plurality of laser emitters are soldered on the circuit board, where a slow axis direction of the light-emitting surfaces of the plurality of laser emitters is perpendicular to the circuit board. 
     According to an aspect of the present disclosure, the plurality of laser emitters are soldered on the circuit board, where a slow axis direction of the light-emitting surfaces of the plurality of laser emitters is parallel to the circuit board, and the light-emitting surfaces of the laser emitter chips in the plurality of laser emitters on the circuit board are staggered with respect to each other in a fast axis direction. 
     According to an aspect of the present disclosure, the laser emitter bracket is a comb structure with a plurality of vertical slots, where laser emitter emitting boards are respectively disposed in the plurality of slots, where light-emitting surfaces of laser emitter chips of the laser emitter emitting boards in the plurality of slots are staggered with respect to each other in a fast axis direction. 
     According to an aspect of the present disclosure, a center of the laser beam shaping element is at the same height as a center of the light-emitting surface of the laser emitter chip. 
     The present disclosure further relates to a lidar. The lidar includes: a rotor, where the rotor has an emitting chamber and a receiving chamber that are separated from each other, where the emitting chamber and the receiving chamber are asymmetrically distributed; a laser emitting system disposed in the emitting chamber; and a receiving system disposed in the receiving chamber; and a wireless power transmission apparatus disposed on a top side inside the lidar and including a wireless power emitting assembly and a wireless power receiving assembly, where the wireless power emitting assembly is separated from the wireless power receiving assembly, the wireless power emitting assembly includes a transmitting coil and a transmitting circuit board, where the transmitting coil is connected to the transmitting circuit board; and the wireless power receiving assembly includes a receiving coil and at least one receiving circuit board, where the receiving coil is separated from the transmitting coil, and the receiving coil is connected to the receiving circuit board. 
     According to an aspect of the present disclosure, the wireless power receiving assembly further includes a magnetic isolation element, where the magnetic isolation element is a magnetic isolation board, where the magnetic isolation board is disposed on a side of the receiving coil away from the transmitting coil. 
     According to an aspect of the present disclosure, the receiving circuit board includes a fourth circuit board and a fifth circuit board, where a first surface of the fourth circuit board is separated from a second surface of the fifth circuit board, the fifth circuit board is connected to the magnetic isolation board, and the magnetic isolation board is disposed on a side of the fifth circuit board facing the fourth circuit board. 
     According to an aspect of the present disclosure, where the laser emitting system includes a laser emitter. The laser emitter includes: a base having a positioning portion thereon; a laser emitter chip disposed on the base and having a light-emitting surface; a laser beam shaping element positioned opposite to the light-emitting surface of the laser emitter chip through the positioning portion. 
     According to an aspect of the present disclosure, the positioning portion includes one or more of a V-shaped groove, a U-shaped groove, and a step, and the laser beam shaping element includes one or more of an optical fiber, a cylindrical lens, a D lens, or an aspherical lens. 
     According to an aspect of the present disclosure, the laser emitter chip is of an edge-emitting type, the light-emitting surface has a slow axis direction and a fast axis direction, where the slow axis direction is parallel to a direction in which the laser beam shaping element extends, and the laser beam shaping element is a fast axis compression element configured to compress an angle of divergence of a laser emitted from the light-emitting surface in the fast axis direction. 
     According to an aspect of the present disclosure, the base is a silicon base, the positioning portion is formed on the silicon base through an etching process, and the laser emitter further includes an electrode disposed on the base, where the electrode is configured to supply power to the laser emitter chip and includes a positive electrode and a negative electrode separated by a partition. 
     According to an aspect of the present disclosure, the positive electrode and the negative electrode are both disposed on the same surface of the base as the laser emitter chip and on a side surface of the base perpendicular to the light-emitting surface. 
     According to an aspect of the present disclosure, the positive electrode and the negative electrode are both disposed on the same surface of the base as the laser emitter chip and on an end surface of the base parallel to the light-emitting surface. 
     According to an aspect of the present disclosure, the laser emitting system includes a laser emitter bracket and at least one laser emitter emitting board fixed to the laser emitter bracket, where the laser emitter emitting board includes a circuit board and a plurality of laser emitters disposed on the circuit board, where light-emitting surfaces of laser emitter chips of the laser emitters are oriented in the same direction. 
     According to an aspect of the present disclosure, the plurality of laser emitters are soldered on the circuit board, where a slow axis direction of the light-emitting surfaces of the plurality of laser emitters is perpendicular to the circuit board. 
     According to an aspect of the present disclosure, the plurality of laser emitters are soldered on the circuit board, where a slow axis direction of the light-emitting surfaces of the plurality of laser emitters is parallel to the circuit board, and the light-emitting surfaces of the laser emitter chips in the plurality of laser emitters on the circuit board are staggered with respect to each other in a fast axis direction. 
     According to an aspect of the present disclosure, the laser emitter bracket is a comb structure with a plurality of vertical slots, where laser emitter emitting boards are respectively disposed in the plurality of slots, where light-emitting surfaces of laser emitter chips of the laser emitter emitting boards in the plurality of slots are staggered with respect to each other in a fast axis direction. 
     According to an aspect of the present disclosure, a center of the laser beam shaping element is at the same height as a center of the light-emitting surface of the laser emitter chip. 
     The present disclosure further relates to a laser emitter. The laser emitter includes: a base having a positioning portion thereon; a laser emitter chip disposed on the base and having a light-emitting surface; a laser beam shaping element positioned opposite to the light-emitting surface of the laser emitter chip through the positioning portion. 
     According to an aspect of the present disclosure, the positioning portion includes one or more of a V-shaped groove, a U-shaped groove, and a step. 
     According to an aspect of the present disclosure, the laser beam shaping element includes one or more of an optical fiber, a cylindrical lens, a D lens, or an aspherical lens. 
     According to an aspect of the present disclosure, the laser emitter chip is of an edge-emitting type, the light-emitting surface has a slow axis direction and a fast axis direction, where the slow axis direction is parallel to a direction in which the laser beam shaping element extends, and the laser beam shaping element is a fast axis compression element configured to compress an angle of divergence of a laser emitted from the light-emitting surface in the fast axis direction. 
     According to an aspect of the present disclosure, the base is a silicon base, and the positioning portion is formed on the silicon base through an etching process. 
     According to an aspect of the present disclosure, the laser emitter further includes an electrode disposed on the base, where the electrode is configured to supply power to the laser emitter chip. 
     According to an aspect of the present disclosure, the electrode includes a positive electrode and a negative electrode separated by a partition. 
     According to an aspect of the present disclosure, the positive electrode and the negative electrode are both disposed on the same surface of the base as the laser emitter chip and on a side surface of the base perpendicular to the light-emitting surface. 
     According to an aspect of the present disclosure, the positive electrode and the negative electrode are both disposed on the same surface of the base as the laser emitter chip and on an end surface of the base parallel to the light-emitting surface. 
     According to an aspect of the present disclosure, a center of the laser beam shaping element is at the same height as a center of the light-emitting surface of the laser emitter chip. 
     The present disclosure further relates to a laser emitter emitting board assembly. The laser emitter emitting board assembly includes: a circuit board; and the plurality of laser emitters described above disposed on the circuit board, where the light-emitting surfaces of the laser emitter chips of the laser emitters are oriented in the same direction. 
     According to an aspect of the present disclosure, the plurality of laser emitters are soldered on the circuit board, where a slow axis direction of the light-emitting surfaces of the plurality of laser emitters is perpendicular to the circuit board. 
     According to an aspect of the present disclosure, the plurality of laser emitters are soldered on the circuit board, where a slow axis direction of the light-emitting surfaces of the plurality of laser emitters is parallel to the circuit board, and the light-emitting surfaces of the laser emitter chips in the plurality of laser emitters on the circuit board are staggered with respect to each other in a fast axis direction. 
     According to an aspect of the present disclosure, the laser emitting system includes a plurality of circuit boards, the plurality of laser emitters are disposed on each of the circuit boards, and the light-emitting surfaces of the laser emitter chips in the laser emitters on the plurality of circuit boards are staggered with respect to each other in the fast axis direction. 
     According to an aspect of the present disclosure, a center of the laser beam shaping element is at the same height as a center of the light-emitting surface of the laser emitter chip. 
     The present disclosure further relates to a lidar. The lidar includes the laser emitting system described above. 
     The present disclosure further relates to a method for encapsulating a laser emitter. The method includes: 
     providing or preparing a base; 
     forming a positioning portion on the base through etching or chemical corrosion; 
     mounting a laser emitter chip on the base; and 
     positioning a laser beam shaping element on the base through the positioning portion, so that a light-emitting surface of the laser emitter chip is opposite to the laser beam shaping element. 
     According to an aspect of the present disclosure, the laser emitter chip is of an edge-emitting type, the light-emitting surface has a slow axis direction and a fast axis direction, where the slow axis direction is parallel to a direction in which the laser beam shaping element extends, and the laser beam shaping element is a fast axis compression element configured to compress an angle of divergence of a laser emitted from the light-emitting surface in the fast axis direction. 
     According to an aspect of the present disclosure, the base is a silicon base. 
     According to an aspect of the present disclosure, the method further includes: causing a center of the laser beam shaping element to be at the same height as a center of the light-emitting surface of the laser emitter chip. 
     The lidar according to the present disclosure has the following beneficial effects by adopting the above technical solutions. 
     (1) The laser emitting apparatus of the lidar according to the present disclosure adopts the laser emitter bracket and a transmitting circuit bracket for respectively mounting the laser emitter emitting board and a transmitting circuit set, so that the space in the emitting chamber of the lidar can be utilized more flexibly, and the volume of the laser emitter emitting board can be reduced to reduce the size and weight of the system, thus reducing the costs and facilitating the miniaturization of the lidar; In addition, the lidar of the present disclosure can easily achieve a greater number of laser beams by combining the layout of the laser emitter emitting board on the laser emitter bracket with the arrangement of laser emitters. 
     (2) The laser emitter array of the laser emitting apparatus of the lidar according to the present disclosure may be non-uniformly distributed. When the laser beam is non-uniformly distributed and is designed with a relatively small number of laser beams, a relatively high vertical angular resolution can be achieved, thus reducing costs and the volume. 
     (3) The lidar according to the present disclosure is provided with a third counterweight structure symmetrically disposed on both sides of the emitting lens set and the receiving lens set, which increases a surface area of the wall of the outer cylinder while improving counterweight flexibility of the rotor, thereby effectively improving a heat dissipation effect of the rotor. The third counterweight structure includes a plurality of first grooves. In addition to increasing the surface area and improving the heat dissipation effect, a first groove structure is disposed on the wall of the outer cylinder of the rotor, so that an overall weight of the rotor can be effectively reduced, and the weight of the rotor is minimized, thus effectively reducing energy consumption during the rotation of the rotor. In addition to improving the heat dissipation effect and reducing the energy consumption, counterweight materials may be flexibly added to the first groove structure to effectively adjust overall balance of the rotor, thus improving flexibility of the overall balance adjustment of the rotor. In addition, a connecting rib is formed between the adjacent first grooves, which acts as a reinforcing rib, improving overall strength of the rotor. 
     (4) In the present disclosure, the lidar divides the wall of the outer cylinder into a movable wall and a fixed wall through a reinforcing strip and a separator, which facilitates mounting of the emitting assembly while improving an overall injection molding process of the rotor. The movable wall structure includes a guide portion, which can effectively reduce resistance for the rotor during rotation, thereby reducing energy consumption for overcoming the resistance. 
     (5) The lidar according to the present disclosure completely isolates the emitting chamber from the receiving chamber through the fixed block, the light isolation sheet, and the light isolation frame that are disposed, which avoids mutual interference between light paths in the emitting chamber and the receiving chamber, thus improving measurement accuracy of the lidar. Moreover, the emitting chamber and the receiving chamber are asymmetrically distributed, so that the emitting chamber and the receiving chamber can be adapted to specific structures and specific volumes of the laser emitting system and the receiving system. 
     (6) The light filter of the receiving apparatus of the lidar according to the present disclosure is disposed on a side of the receiving device facing the second mirror set, so that stray light can be filtered. The APD detector of the receiving device is further covered with a metal protective shell, which can protect the receiving device and avoid foreign matter such as dust from entering and damaging the device. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       To describe the technical solutions in the embodiments of the present disclosure more clearly, the following briefly describes the accompanying drawings required for describing the embodiments. The accompanying drawings in the following description show merely some embodiments of the present disclosure, and a person of ordinary skill in the art may still derive other drawings from these accompanying drawings without creative efforts 
         FIG. 1  is a schematic diagram of a structure of a rotor of a lidar, in accordance with an embodiment of this disclosure; 
         FIG. 2  is a light path diagram of a lidar, in accordance with an embodiment of this disclosure; 
         FIG. 3  is a top view of  FIG. 1 ; 
         FIG. 4  is a schematic diagram of another structure of a rotor of a lidar, in accordance with an embodiment of this disclosure; 
         FIG. 5  is a schematic diagram of another structure of a rotor of a lidar, in accordance with an embodiment of this disclosure; 
         FIG. 6  is a schematic diagram of another structure of a rotor of a lidar, in accordance with an embodiment of this disclosure; 
         FIG. 7  is a schematic diagram of another structure of a rotor of a lidar, in accordance with an embodiment of this disclosure; 
         FIG. 8  is a schematic diagram of another structure of a rotor of a lidar, in accordance with an embodiment of this disclosure; 
         FIG. 9  is a schematic structural diagram of a bottom plate of a rotor of a lidar, in accordance with an embodiment of this disclosure; 
         FIG. 10  is a schematic structural diagram of a baseplate of a lidar, in accordance with an embodiment of this disclosure; 
         FIG. 11  is a schematic structural diagram of a pedestal of a lidar, in accordance with an embodiment of this disclosure; 
         FIG. 12  is a cross-sectional view of a pedestal of a lidar, in accordance with an embodiment of this disclosure; 
         FIG. 13  is a schematic diagram of a laser emitting apparatus according to Embodiment 3 of the present disclosure; 
         FIG. 14  is a schematic diagram of assembly of a laser emitter bracket and a laser emitter emitting board according to Embodiment 3 of the present disclosure; 
         FIG. 15  is a three-dimensional schematic diagram of a laser emitter bracket according to Embodiment 3 of the present disclosure; 
         FIG. 16  is a schematic diagram of assembly of a transmitting circuit bracket and a transmitting circuit set according to the present disclosure; 
         FIG. 17  is a three-dimensional schematic diagram of a transmitting circuit bracket according to the present disclosure; 
         FIG. 18  is a schematic diagram of a laser emitter bracket according to Embodiment 4 of the present disclosure; 
         FIG. 19  is a schematic diagram of arrangement of a laser emitter emitting board according to Embodiment 4 of the present disclosure; 
         FIG. 20  is a schematic diagram of arrangement of a laser emitter emitting board according to Embodiment 5 of the present disclosure; 
         FIG. 21  is a schematic diagram of a lidar receiving system according to Embodiment 6 of the present disclosure; 
         FIG. 22  is a schematic diagram of a lidar receiving system according to Embodiment 6 of the present disclosure from another perspective; 
         FIG. 23  is a schematic diagram of a receiving apparatus of a lidar receiving system according to Embodiment 6 of the present disclosure; 
         FIG. 24  is a front view of a receiving device according to Embodiment 6 of the present disclosure; 
         FIG. 25  is a left view of a receiving device according to Embodiment 6 of the present disclosure; 
         FIG. 26  is a schematic diagram of a receiving circuit bracket according to Embodiment 6 of the present disclosure; 
         FIG. 27  is a schematic diagram of a receiving circuit bracket according to Embodiment 6 of the present disclosure from another perspective; 
         FIG. 28  is a partial schematic structural diagram of a wireless power transmission apparatus according to Embodiment 9 of the utility model; 
         FIG. 29  is a partial structural front view of a wireless power transmission apparatus according to Embodiment 9 of the utility model; 
         FIG. 30  is a schematic structural diagram of a lidar according to Embodiment 1 of the utility model; 
         FIG. 31A  is a schematic diagram of a lidar;  FIG. 31B  is a schematic diagram of an edge-emitting laser emitter chip; 
         FIG. 31C  is a schematic diagram of a configuration of an existing semiconductor laser emitter chip and an existing circuit board; 
         FIG. 32  is a schematic diagram of another configuration of an existing semiconductor laser emitter chip and an existing circuit board; 
         FIG. 33A  is a three-dimensional diagram of a laser emitter according to a first aspect of the present disclosure viewed from a front side,  FIG. 33B  is a three-dimensional diagram of the laser emitter viewed from a rear side, and  FIG. 33C  and  FIG. 33D  are respectively renderings of  FIG. 33A  and  FIG. 33B ; 
         FIG. 34A  shows angles of divergence of a laser beam emitted by the laser emitter chip in a slow axis direction and in a fast axis direction;  FIG. 34B  and  FIG. 34C  show a situation in which an angle of divergence of a laser beam emitted by a laser emitter chip in a fast axis direction decreases after the laser beam passes through a D lens and an optical fiber; 
         FIG. 35A  and  FIG. 35B  show a laser emitter according to another embodiment of the present disclosure; 
         FIG. 36A  and  FIG. 36B  show a laser emitter according to another embodiment of the present disclosure, and  FIG. 36C  and  FIG. 36D  are respectively renderings of  FIG. 36A  and  FIG. 36B ; 
         FIG. 37A  and  FIG. 37B  show variations of the laser emitters according to  FIG. 36A  and  FIG. 36B ; 
         FIG. 38  shows a laser emitter emitting board assembly according to an exemplary embodiment of the present disclosure; 
         FIG. 39A  shows a laser emitter emitting board assembly according to an exemplary embodiment of the present disclosure, and  FIG. 39B  shows a laser emitter emitting board assembly according to another preferred embodiment of the present disclosure; 
         FIG. 40  shows a laser emitter emitting board assembly according to an exemplary embodiment of the present disclosure; 
         FIG. 41  shows a laser emitter emitting board assembly according to an exemplary embodiment of the present disclosure; and 
         FIG. 42  shows a method for encapsulating a laser emitter according to the present disclosure. 
     
    
    
     The following supplementary description is given to the accompanying drawings. 
       1 —Rotor,  11 —Outer cylinder,  111 —First mounting plane,  112 —Third mounting plane,  113 —Upper plane,  1131 —First counterweight structure,  114 —Movable wall,  1141 —First counterweight block,  1142 —Arc-shaped portion,  1143 —Guide portion,  115 —Fixed wall,  12 —Inner cylinder,  121 —Second mounting plane,  122 —Fourth mounting plane,  123 —Attachment surface,  13 —Emitting chamber,  14 —Receiving chamber,  15 —Reinforcing strip,  16 —separator,  161 —Second counterweight structure,  17 —First bottom plate,  171 —Recessed portion,  1711 —First recessed portion,  1712 —Second recessed portion,  1713 —Third recessed portion,  2 —baseplate,  21 —Second counterweight block,  3 —Pedestal,  31 —Drying cavity,  32 —Central shaft,  33 —Driving apparatus,  34 —First bearing,  35 —Second bearing,  36 —enclosure;  37 —Top cap;  41 —Light isolation sheet  42 —Light isolation frame,  5 —Third counterweight structure,  51 —First groove,  52 —Connecting rib,  6 —Conductive component,  7 —First through hole,  71 —Sealing gasket,  8 —Fixed block,  81 —Lapping strip,  9 —Avoidance groove,  10 —Cover plate assembly,  101 —First cover plate,  102 —Second cover plate,  103 —Receiving chamber cover plate; 
       201 —Laser emitting apparatus;  2011 —Laser emitter bracket;  20111 —Second bottom plate;  201111 —First mounting hole;  20112 —First side plate;  201121 —Comb;  201122 —Slot;  201 —Transmitting circuit set;  20121 —Transmitting motherboard;  20122 —First transmitting daughterboard;  20123 —Second transmitting daughterboard;  20124 —Third transmitting daughterboard;  2013 —Transmitting circuit bracket;  20131 —Third bottom plate;  201311 —Second mounting hole;  20132 —Second side plate;  201321 —First side surface;  201322 —Second side surface;  20133 —Assembling post;  201331 —First assembling hole;  20134 —Protrusion;  2014 —Laser emitter emitting board;  2015 —Laser emitter;  20161 —First screw;  20162 —First nut;  20163 —First washer;  20164 —Second screw.  202 —First mirror set;  2021 —First mirror;  2022 —Second mirror;  203 —Emitting lens set; 
       301 —Receiving lens set;  302 —Second mirror set;  3021 —Third mirror;  3022 —Fourth mirror;  303 —Receiving apparatus;  3031 —Light filter;  3032 —Receiving device;  30321 —Substrate;  30323 —Protective shell;  3033 —Receiving circuit bracket;  30331 —Fourth bottom plate;  303311 —Protruding plate;  303312 —Assembling lug;  303313 —Third mounting hole;  30332 —Third side plate;  303321 —Third side surface;  303322 —Fourth side surface;  303323 —Second groove;  303324 —Second through hole;  303325 —Positioning plate;  303326 —Second assembling hole;  3034 —Receiving circuit board;  30341 —First circuit board;  30342 —Second circuit board;  30343 —Third circuit board;  3035 —Third screw;  3036 —Second nut;  3037 —Second washer;  3038 —Fourth screw; 
       401 —Receiving coil;  402 —Magnetic isolation board;  4021 —Third connecting portion;  4022 —Fourth connecting portion;  4023 —Third through hole;  403 —Receiving circuit board;  4031 —Fourth circuit board;  40311 —Fourth through hole;  40312 —First perforation;  40313 —Second perforation;  4032 —Fifth circuit board;  40321 —First connecting portion;  40322 —Second connecting portion;  40323 —Glue injection hole;  40324 —Fifth through hole;  404 —Copper post tube;  4051 —Fifth screw;  4052 —Third nut;  406 —Transmitting coil;  407 —Transmitting circuit board. 
     DETAILED DESCRIPTION 
     The technical solutions of the embodiments of the present disclosure are clearly and completely described in the following with reference to the accompanying drawings of the embodiments of the present disclosure. The described embodiments are merely some but not all of the embodiments of the present disclosure. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments of the present disclosure without creative efforts shall fall within the protection scope of the present disclosure. 
     The phrase “an embodiment”, “one embodiment”, or “embodiments” as used herein refers to a particular feature, structure, or characteristic that can be included in at least one implementation of the present disclosure. In the description of the present disclosure, it should be understood that orientation or position relationships indicated by the terms such as “upper”, “lower”, “top”, and “bottom” are based on orientation or position relationships shown in the accompanying drawings, and are used only for ease and brevity of illustration and description of the present disclosure, rather than indicating or implying that the mentioned apparatus or component needs to have a particular orientation or needs to be constructed and operated in a particular orientation. Therefore, such terms should not be construed as limiting of the present disclosure. In addition, terms “first” and “second” are used merely for the purpose of description, and shall not be construed as indicating or implying relative importance or implying a quantity of indicated technical features. Therefore, a feature limited by “first” or “second” may explicitly or implicitly include one or more of the features. Moreover, the terms “first”, “second”, and so on are intended to distinguish between similar objects rather than describe a specific order. It is to be understood that data used in this way is exchangeable in a proper case, so that the embodiments of the present disclosure described herein can be implemented in another order except those shown or described herein. 
     In the description of the present disclosure, it should be understood that directions or location relationships indicated by terms “center”, “longitudinal”, “landscape”, “length”, “width”, “thickness”, “upper”, “lower”, “front”, “rear”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inner”, “outer”, “clockwise”, and “counterclockwise” are directions or location relationships shown based on the accompanying drawings, are merely used for the convenience of describing the present disclosure and simplifying the description, but are not used to indicate or imply that a device or an element must have a particular direction or must be constructed and operated in a particular direction, and therefore, cannot be understood as a limitation to the present disclosure. In the descriptions of the present disclosure, unless otherwise explicitly specified, “multiple” means two or more than two. 
     In the descriptions of the present disclosure, it should be noted that, unless otherwise specified or defined, the terms such as “mount”, “connect”, and “connection” should be understood in a broad sense, for example, the connection may be a fixed connection, a detachable connection, or an integral connection; or the connection may be a mechanical connection, or may be an electrical connection or communication with each other; or the connection may be a direct connection, an indirect connection through an intermediary, or internal communication between two components or mutual interaction relationship between two components. The specific meanings of the above terms in the present disclosure may be understood according to specific circumstances for a person of ordinary skill in the art. 
     In the present disclosure, unless otherwise explicitly stipulated and restricted, that a first feature is “on” or “under” a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but in contact by using other features therebetween. In addition, that the first feature is “on”, “above”, or “over” the second feature includes that the first feature is right above and on the inclined top of the second feature or merely indicates that a level of the first feature is higher than that of the second feature. That the first feature is “below”, “under”, or “beneath” the second feature includes that the first feature is right below and at the inclined bottom of the second feature or merely indicates that a level of the first feature is lower than that of the second feature. 
     Many different implementations or examples are provided in the following disclosure to implement different structures of the present disclosure. To simplify the disclosure of the present disclosure, components and settings in particular examples are described below. Certainly, they are merely examples and are not intended to limit the present disclosure. In addition, in the present disclosure, reference numerals and/or reference letters may be repeated in different examples. The repetition is for the purposes of simplification and clearness, and a relationship. Moreover, the present disclosure provides examples of various particular processes and materials, but a person of ordinary skill in the art may be aware of application of another process and/or use of another material. 
     First Aspect 
     Various embodiments of a first aspect of the present disclosure relate to a lidar, which are described in detail below with reference to  FIG. 1  to  FIG. 30 . 
     Embodiment 1 
     Embodiment 1 relates to a lidar. The lidar includes a rotor  1 , a laser emitting system, and a receiving system. The rotor  1  has an emitting chamber  13  and a receiving chamber  14  that are separated from each other (see  FIG. 3 ). The laser emitting system is disposed in the emitting chamber  13 , and the receiving system is disposed in the receiving chamber  14 . The laser emitting system and the receiving system are described in detail below. 
     As shown in  FIG. 13 , the laser emitting system includes a laser emitting apparatus  201 . The laser emitting apparatus  201  includes a laser emitter bracket  2011 , a transmitting circuit set  2012 , a transmitting circuit bracket  2013 , and at least one laser emitter emitting board  2014 . The laser emitter bracket  2011  may be separated from the transmitting circuit bracket  2013 . The laser emitter emitting board  2014  is mounted to the laser emitter bracket  2011 , and at least one laser emitter  2015  is disposed on the laser emitter emitting board  2014  (see  FIG. 14 ). The transmitting circuit set  2012  is mounted to the transmitting circuit bracket  2013 , and the transmitting circuit set  2012  is electrically connected to the laser emitter emitting board  2014 . 
     The laser emitting apparatus  201  further includes a plurality of flexible electrical connectors. The transmitting circuit set  2012  is connected to the laser emitter emitting board  2014  through the flexible electrical connectors, and the transmitting circuit set  2012  may supply driving signals and power to the laser emitter emitting board  2014  through the flexible electrical connectors. 
     As shown in  FIG. 12 , the lidar further includes a pedestal  3 , an enclosure  36 , and a top cap  37 . One end of the enclosure  36  is mated with the pedestal  3 , and the other end of the enclosure  36  is mated with the top cap  37 . The pedestal  3 , the enclosure  36 , and the top cap  37  are sequentially connected to form an enclosed cavity, which is configured to accommodate the rotor  1 , the laser emitting system, and the receiving system. 
     As shown in  FIG. 6  and  FIG. 7 , the laser emitting system further includes a first mirror set  202  and an emitting lens set  203 . The first mirror set  202  is configured to receive a laser beam emitted by the laser emitter  2015  and to change a path of the laser beam, so that the laser beam is incident on the emitting lens set  203 . The emitting lens set  203  is configured to emit detection light. 
     As shown in  FIG. 6 ,  FIG. 7 , and  FIG. 21 , the receiving system includes a receiving lens set  301 , a second mirror set  302 , and a receiving apparatus  303 . The receiving lens set  301  is configured to converge light reflected from a to-be-detected object, and the second mirror set  302  is configured to change a path of the beam, so that the reflected light is incident on the receiving apparatus  303 . 
     According to an exemplary embodiment of the present disclosure, the emitting chamber  13  and the receiving chamber  14  are asymmetrically distributed. Asymmetrically distributing the emitting chamber and the receiving chamber facilitates proper arrangement of the laser emitting system and the receiving system. As described above, the laser emitting system includes the laser emitter bracket  2011  (on which the laser emitter emitting board  2014  is carried), the transmitting circuit bracket  2013  (on which the transmitting circuit set  2012  is carried), the first mirror set  202 , and the emitting lens set  203 . A number of the components and a weight are relatively large. The receiving system includes a receiving lens set  301 , a second mirror set  302 , and a receiving apparatus  303 . A number of the components and a weight are relatively small. Therefore, asymmetrically arranging the emitting chamber and the receiving chamber can facilitate uniform distribution of the components in the laser emitting system and the receiving system in the lidar as much as possible, avoiding weight unbalance. 
     The lidar includes a pedestal  3  and an enclosure  36 . The pedestal  3  and the enclosure  36  are mated with each other to form an enclosed cavity. The rotor  1  is disposed on the pedestal  3 , and the rotor  1  can rotate relative to the pedestal  3 . The lidar further includes a wireless power transmission apparatus. The wireless power transmission apparatus includes a wireless power emitting assembly and a wireless power receiving assembly. The wireless power emitting assembly is disposed on a side of a top of the enclosure  36  facing the pedestal  3 , and the wireless power receiving assembly is disposed on a side of the rotor  1  facing the wireless power emitting assembly. 
     As shown in  FIG. 11  and  FIG. 12 , the lidar further includes a central shaft  32 , and a wire groove is provided on a side wall of the central shaft  32 . The lidar further includes a plurality of electrical connecting wires. The electrical connecting wires are laid in the wire groove. One end of the electrical connecting wire is connected to the wireless power transmission emitting assembly, and the other end of the electrical connecting wire is connected to a circuit part in the pedestal. 
     Embodiment 2 
     A second embodiment of the present disclosure relates to a lidar apparatus, which is described with reference to  FIG. 1  to  FIG. 12 . As shown in  FIG. 1 , the lidar apparatus includes a rotor  1 . The rotor  1  includes an outer cylinder  11  and an inner cylinder  12 . A mounting structure for mounting a receiving lens set  301  and an emitting lens set  203  is disposed on a wall of the outer cylinder  11 , and a third counterweight structure  5  is distributed on both sides of the mounting structure, which is shown in  FIG. 7 . The third counterweight structure  5  includes a counterweight structure I and a counterweight structure II. The counterweight structure I and the counterweight structure II both include a plurality of first grooves  51 . Preferably, structures of the plurality of first grooves  51  may be the same or different. As an exemplary embodiment, the plurality of first grooves  51  forming the third counterweight structure  5  are given by way of example in this embodiment. The third counterweight structure includes  12  first grooves  51 . Specifically,  4  rectangular grooves are linearly arranged in a vertical direction of the wall of the outer cylinder  11  and  8  wedge-shaped grooves are symmetrically disposed on both sides of the rectangular grooves. The rectangular grooves have the same depth, and depths of the wedge-shaped grooves gradually increase inward in a radial direction of the rotor  1  in a direction of approaching the rectangular grooves. Specifically, the depths of the rectangular grooves and the gradually changing depths of the wedge-shaped grooves are set according to actual conditions. Further, a connecting rib  52  is formed between two adjacent first grooves  51 , which acts as a reinforcing rib, improving overall strength of the rotor  1 . Moreover, by disposing the third counterweight structures  5  consisting of the plurality of first grooves  51  on both sides of the mounting structure, a surface area of the wall of the outer cylinder of the rotor  1  is increased, improving a heat dissipation effect of the rotor  1 . In addition, the provided first grooves  51  reduce an overall weight of the rotor  1 , enabling lightweight of the rotor  1 , which effectively reduces energy consumption of the rotor  1  during rotation. Further, different counterweight materials may be flexibly stuffed into the first groove  51  to adjust overall balance of the rotor  1 , which improves flexibility of overall balance adjustment for the rotor  1 . 
     As shown in  FIG. 7 , the third counterweight structure  5  is symmetrically distributed on both sides of the mounting structure for the receiving lens set  301  and the emitting lens set  203  for adjusting the balance of the rotor  1 . As described above, the laser emitting system has a large number of components and a relatively large weight, and therefore the laser emitting system side may be relatively heavy and the receiving system side may be relatively light. To this end, an appropriate counterweight may be placed in the first groove  51  of the counterweight structure  5  of the receiving system side. For example, the counterweight is bonded in the first groove  51 , so that the rotor  1  achieves weight balance about a rotating shaft thereof, to avoid problems such as vibration or accuracy decrease caused by unbalanced weight during high-speed rotation. Those skilled in the art may select a number, materials, and positions of counterweights under different circumstances. 
     It may be understood that the symmetrical distribution of the third counterweight structure  5  on both sides of the mounting structure is merely an exemplary solution, and distribution of the third counterweight structure is not restricted. The third counterweight structure may be disposed at any position on the rotor under different circumstances. 
     Further, as shown in  FIG. 1  and  FIG. 3 , an accommodation cavity is formed between the outer cylinder  11  and the inner cylinder  12 , and a separator  16  is disposed in the accommodation cavity. One side of the separator  16  is connected to the outer cylinder  11 , and the other side of the separator  16  is connected to the inner cylinder  12 . The separator  16  divides the accommodation cavity into an emitting chamber  13  and a receiving chamber  14 . Volumes of the emitting chamber  13  and the receiving chamber  14  may not be equal, or the emitting chamber  13  and the receiving chamber  14  may be asymmetrically distributed on the rotor. Specifically, the inner cylinder  12  includes an inner wall of the inner cylinder inner wall and an inner cylinder outer wall. The outer cylinder  11  includes an outer cylinder inner wall and an outer cylinder outer wall. The accommodation cavity is formed between the outer cylinder inner wall and the inner cylinder outer wall, and the outer cylinder inner wall and the inner cylinder outer wall form an inner wall of the accommodation cavity. An avoidance groove  9  is formed on each of the inner cylinder outer wall and the outer cylinder inner wall, which is shown in  FIG. 6 . It may be understood that a number and positions of avoidance grooves  9  may be set according to assembly positions of assembly components, to avoid assembly interference between the assembly components. A size of the avoidance groove may be determined according to a size of the assembly component. Specifically, in this embodiment, the number and the positions of the avoidance grooves  9  are preferably set based on the assembly positions of the assembly components. Specifically, as shown in  FIG. 3 , a first mounting plane  111  and a third mounting plane  112  are disposed on the inner wall of the outer cylinder  11 , and a second mounting plane  121 , a fourth mounting plane  122 , and an attachment surface  123  are disposed on the outer wall of the inner cylinder  12 . The first mounting plane  111  and the second mounting plane  121  are disposed in the emitting chamber  13 , and the third mounting plane  112  and the fourth mounting plane  122  are disposed in the receiving chamber  14 . The attachment surface  123  spans the emitting chamber  13  and the receiving chamber  14 . The first mounting plane  111  is opposite to the second mounting plane  121 . The second mounting plane  121  and the fourth mounting plane  122  are connected through the attachment surface  123 . The third mounting plane  112  is opposite to the fourth mounting plane  122 . Further, avoidance grooves  9  are disposed on both sides of all of the first mounting plane  111 , the second mounting plane  121 , the third mounting plane  112 , and the fourth mounting plane  122 . 
     As shown in  FIG. 6  and  FIG. 13 , a laser emitting apparatus  201  and a first mirror set  202  are disposed in the emitting chamber  13 . 
     As shown in  FIG. 6 , the first mirror set  202  includes a first mirror  2021  and a second mirror  2022  for reflecting detection light of the laser emitting apparatus  201  for the second time. Specifically, with reference to  FIG. 3  and  FIG. 6 , the first mirror  2021  is attached to the first mounting plane  111 , and the second mirror  2022  is attached to the second mounting plane  121 . The avoidance grooves  9  on both sides of the first mounting plane  111  and the second mounting plane  121  provide an avoidance space for mounting the first mirror  2021  and the second mirror  2022 , which avoids interference between the first mirror  2021  and the second mirror  2022  and the cylinder walls on both sides of the mounting plane while facilitating the mounting of the first mirror  2021  and the second mirror  2022 . 
     The emitting lens set  203  and the receiving lens set  301  are symmetrically disposed. The emitting lens set  203  is in communication with the emitting chamber  13 , and the receiving lens set  301  is in communication with the receiving chamber  14 . 
     As shown in  FIG. 6 , a second mirror set  302  and a receiving apparatus  303  are disposed in the receiving chamber  14 . The second mirror set  302  includes a third mirror  3021  and a fourth mirror  3022  for reflecting, to the receiving apparatus  303  for the second time, reflected light passing through the receiving lens set  301 . Specifically, the third mirror  3021  is attached to the third mounting plane  112 , and the fourth mirror  3022  is attached to the fourth mounting plane  122 . The avoidance grooves  9  on both sides of the third mounting plane  112  and the fourth mounting plane  122  provide an avoidance space for mounting the third mirror  3021  and the fourth mirror  3022 , which avoids interference between the third mirror  3021  and the fourth mirror  3022  and the cylinder walls on both sides of the mounting plane while facilitating the mounting of the third mirror  3021  and the fourth mirror  3022 . 
     In the above embodiment, the first mirror set  202  and the second mirror set  302  both include two mirrors. Those skilled in the art easily understand that the protection scope of the present disclosure is not limited to the specific number of mirrors. One mirror may be included, or more mirrors may be included, which may be determined by those skilled in the art according to different designs of the lidar, for example, a size and an optical performance parameter of the lidar, which all fall within the protection scope of the present disclosure. 
     As shown in  FIG. 2 ,  FIG. 21 , and  FIG. 22 , the lidar apparatus further includes a light isolation sheet  41  and a light isolation frame  42 . The light isolation sheet  41  is configured to isolate the emitting lens set  203  from the receiving lens set  301 . One end of the light isolation sheet  41  is disposed between the second mirror  2022  and the fourth mirror  3022 , and the other end of the light isolation sheet  41  is attached to the light isolation frame  42 . 
     It may be understood that the light isolation sheet  41  is mainly intended to isolate the emitting lens set  203  from the receiving lens set  301 , and its shape includes but is not limited to a rectangular shape, a regular T shape or an irregular T shape. Preferably, a thickness of the light isolation sheet  41  is  2  mm to  5  mm for bearing its own gravity after being mounted, thus avoiding light leakage caused by untight attachment between the emitting lens set  203  and the receiving lens set  301  as a result of bending of the light isolation sheet  41  due to gravity. 
     As shown in  FIG. 1  and  FIG. 7 , the rotor  1  further includes a first bottom plate  17  and an upper plane  113 . One end of the light isolation frame  42  is disposed on the first bottom plate  17  of the rotor  1 , and the other end of the light isolation frame  42  is flush with the upper plane  113  of the rotor  1 , or may protrude out of the upper plane  113  of the rotor  1 . The light isolation frame  42  is preferably a T-shaped structure. After the light isolation sheet  41  and the light isolation frame  42  are mounted, a height of the light isolation frame  42  is higher than that of the light isolation sheet  41 , further isolating stray light and inhibiting interference between light. 
     The first bottom plate  17  is configured to seal a gap between a bottom of the inner cylinder  12  and a bottom of the outer cylinder  11 . The transmitting circuit bracket  2013 , the laser emitter emitting board bracket  2011 , and the receiving circuit board bracket  3033  are all disposed on the first bottom plate  17 , and their positions on the first bottom plate  17  may be adjusted under different circumstances. In an exemplary solution, the first bottom plate  17  includes an upper plane and a lower plane, and a recessed portion  171  is disposed on the upper plane, which is shown in  FIG. 1 . Preferably, as shown in  FIG. 9 , the upper plane includes a first recessed portion  1711 , a second recessed portion  1712 , and a third recessed portion  1713 . The first recessed portion  1711  and the second recessed portion  1712  are both disposed on the first bottom plate at a bottom of the emitting chamber  13 , and the first recessed portion  1711  and the second recessed portion  1712  are disposed on both sides of a reinforcing strip  15  (refer to  FIG. 1 ). The third recessed portion  1713  is disposed on a first bottom plate at a bottom of the receiving chamber  14 , and the transmitting circuit bracket  2013 , the laser emitter emitting board bracket  2011 , and the receiving circuit board bracket  3033  are all disposed in the recessed portion  171 . The lower plane of the first bottom plate  17  is also provided with a plurality of recessed portions  171 . Preferably, the plurality of recessed portions include a fourth recessed portion, a fifth recessed portion, and a sixth recessed portion in a one-to-one correspondence with the first recessed portion  1711 , the second recessed portion  1712 , and the third recessed portion  1713 . By disposing the recessed portion  171 , the overall weight of the rotor  1  can be reduced, enabling lightweight of the rotor  1 , thus reducing the energy consumption of the rotor  1  during rotation. 
     It may be understood that a number and positions of recessed portions  171  on the upper plane and the lower plane of the first bottom plate  17  that are set are merely an exemplary solution, and the number and the positions are not limited. The specific positions and number may be set under different circumstances. 
     Further, as shown in  FIG. 3  and  FIG. 6 , the second mirror  2022  is attached to the second mounting plane  121 . After the fourth mirror  3022  is attached to the fourth mounting plane  122 , a part of the second mirror  2022  extending out of the second mounting plane  121  abuts against a side of the light insulation sheet  41 , and a part of the fourth mirror  3022  extending out of the fourth mounting plane  122  abuts against the other side of the light insulation sheet  41 . A triangular accommodation space is formed between the extending part of the second mirror  2022  and the extending part of the fourth mirror  3022 . 
     Further, as shown in  FIG. 6 , a fixed block  8  is further disposed in the accommodation cavity. Preferably, in this embodiment, the fixed block  8  is a triangular structure, and the fixed block  8  includes an upper surface, a lower surface, a first side surface, and a second side surface. A lapping strip  81  is fixedly disposed on the upper surface, and the lower surface abuts against the second mirror  2022  and the fourth mirror  3022 . The first side surface is attached to the attachment surface  123 , and the second side surface is attached to the inner wall of the outer cylinder  11 . One end of the lapping strip  81  is lapped on the inner cylinder  12 , and the other end of the lapping strip  81  is lapped on the outer cylinder  11 . By disposing the fixed block  8 , the reflection chamber  13  is separated from the receiving chamber  14 . The fixed block  8  is preferably a triangular structure, which is adapted to the triangular shape of the triangular accommodation space formed between the second mirror  2022  and the fourth mirror  3022 . In addition, the fixed block with the triangular structure is disposed above the second mirror  2022  and the fourth mirror  3022 , so that a spacing between the mirror and a top of the rotor  1  can be filled, to avoid interference between detection light and received light, thus improving detection accuracy. 
     Specifically, a principle of the light path is as follows. The laser emitter  2015  of the laser emitting apparatus  201  (refer to  FIG. 2 ) emits a laser beam as detection light, which is sent to the first mirror  2021  and is reflected by the first mirror  2021  to the second mirror  2022 . Then, the second mirror  2022  reflects the detection light to the emitting lens set  203 , which passes through the emitting lens set  203  and is then irradiated on a to-be-detected object, and the reflected light is reflected to the receiving lens set  301  by the to-be-detected object. The reflected light reflected by the detected object is incident on the third mirror  3021  after passing through the receiving lens set  301 , and is reflected to the fourth mirror  3022  by the third mirror  3021 , and is then reflected to the receiving apparatus  303  after being reflected by the fourth mirror  3022  for the second time. 
     As shown in  FIG. 4 , the rotor  1  further includes a cover plate assembly  10 . The cover plate assembly  10  includes an emitting chamber cover plate and a receiving chamber cover plate  103 . The emitting chamber cover plate is covered over the emitting chamber  13 , and the receiving chamber cover plate  103  is covered over the receiving chamber  14 . Preferably, the emitting chamber cover plate includes a first cover plate  101  and a second cover plate  102 . The first cover plate  101  is disposed above the laser emitting apparatus  201 , and the second cover plate  102  is disposed above the first mirror set  202 . 
     Further, baffle structures protruding from positions on the first cover plate  101 , the second cover plate  102 , and the receiving chamber cover plate  103  corresponding to the avoidance grooves  9 . Steps for supporting the first cover plate  101 , the second cover plate  102 , and the receiving chamber cover plate  103  are disposed on a top of the inner wall of the accommodation cavity. Depths of the steps match thicknesses of the first cover plate  101 , the second cover plate  102 , and the receiving chamber cover plate  103 . 
     As shown in  FIG. 4 , a first through hole  7  is disposed on the emitting chamber cover plate for a conductive component  6  to pass through, to supply power to the transmitting circuit board  1312 . Preferably, the first through hole  7  is disposed on the second cover plate  102  or on the receiving chamber cover plate  103  for the conductive component  6  to pass through. The conductive component  6  is preferably a flexible electrical connector, and a sealing gasket  71  is disposed on the first through hole, to implement sealing of the first through hole, thus avoiding shaking of the conductive component  6  during rotation of the rotor  1 , and improving stability of circuit transmission. 
     Further, in this embodiment, as an exemplary solution, a reinforcing strip  15  is further disposed in the accommodation cavity, which is shown in  FIG. 1 . One end of the reinforcing strip  15  is connected to the outer cylinder  11 , and the other end of the reinforcing strip  15  is connected to the inner cylinder  12 . The reinforcing strip  15  and the separator  16  are disposed at a specific angle relative to each other. Preferably, a value of the angle between the reinforcing strip  15  and the separator  16  is from 120° to 150°. Disposing the reinforcing strip  15  facilitates improvement of strength of the rotor  1 , especially strength of the emitting chamber  13 . Specifically, the reinforcing strip  15  separates the emitting apparatus  201  and the first mirror set  202  on both sides of the reinforcing strip. The reinforcing strip  15  and the separator  16  separate the wall of the outer cylinder  11  into a movable wall  114  and a fixed wall  115 . As shown in  FIG. 4 , the movable wall  114  and the fixed wall  115  are detachably connected. Preferably, the movable wall  114  is snap-fitted to the fixed wall  115 . Specifically, the fixed wall  115  is a major arc structure, including a first open end and a second open end. The first open end and the second open end are both provided with a slot structure. The movable wall  114  is a minor arc structure mated with the fixed wall  115  with the major arc structure, including a first connecting end and a second connecting end. The first connecting end and the second connecting end are snap-fitted to the slot structure. The separator  16  separates the accommodation cavity into an emitting chamber  13  and a receiving chamber  14 . The emitting chamber  13  and the receiving chamber  14  may have different volumes and are asymmetrically distributed. 
     It may be understood that the movable wall  114  is not restricted to be snap-fitted to the fixed wall  115 , and may also be connected through threads or riveting. The above snap-fit is merely an exemplary embodiment, and the connection between the movable wall and the fixed wall is not limited. 
     Dividing the wall of the outer cylinder  11  into a movable wall  114  and a fixed wall  115  through the reinforcing strip  15  and the separator  16  facilitates the mounting of the laser emitting apparatus  201  while improving the overall injection molding process of the rotor  1 . 
     The movable wall  114  is made of copper, aluminum alloy or other materials with a good heat dissipation effect and a specified hardness, and the fixed wall  115  is made of aluminum alloy. 
     Further, as shown in  FIG. 4  and  FIG. 8 , the movable wall  114  includes an arc-shaped portion  1142  and a guide portion  1143 . The arc-shaped portion  1142  and the guide portion  1143  are smoothly connected. The guide portion  1143  has a non-uniform wall thickness, and the arc-shaped portion  1142  has a uniform wall thickness. 
     As an exemplary solution, a minimum wall thickness of the guide portion  1143  is greater than a wall thickness of the arc-shaped portion  1142 . The guide portion  1143  is a streamlined structure, which can reduce the resistance for the rotor  1  during rotation. In addition, the movable wall  114  is made of materials such as copper, copper-aluminum alloy, or the like, which can accelerate dissipation of heat generated by the transmitting circuit board  1312  during operation. By manufacturing the fixed wall  115  with aluminum alloy, the weight of the rotor  1  can be reduced. 
     Further, as shown in  FIG. 8 , at least one first counterweight block  1141  is disposed on the movable wall  114 . 
     As an exemplary solution, in this embodiment, one first counterweight block  1141  is disposed on the movable wall  114 . The first counterweight block  1141  is disposed at a joint between the guide portion  1143  and the arc-shaped portion  1142  of the movable wall  114 , and the first counterweight block  1141  is disposed close to a top of the movable wall  114 . 
     The first counterweight block  1141  is a hammer-shaped structure, which includes a front end and a rear end. A thickness of the front end is less than a thickness of the rear end. The front end is disposed close to the guide portion  1143 , and the rear end is disposed close to the arc-shaped portion  1142 . The first counterweight block  1141  is threadably connected to the movable wall  114 . 
     Further, as shown in  FIG. 1  and  FIG. 2 , the lidar further includes a baseplate  2 . The baseplate  2  is configured to support the rotor  1 .  FIG. 10  shows the baseplate  2 . As shown in the figure, at least one second counterweight block  21  is disposed on the baseplate  2 . The second counterweight block  21  is accommodated in the recessed portion on the lower plane of the first bottom plate  17  of the rotor  1 . 
     As an exemplary solution, in this embodiment, there is one second counterweight block  21 . The second counterweight block  21  is disposed below the light receiving member of the optical assembly. 
     The first counterweight block  1141  and the second counterweight block  21  are disposed to adjust the balance of the rotor  1 . 
     Further, as shown in  FIG. 30  and  FIG. 11 , the lidar further includes a rotor pedestal  3 . The baseplate is disposed on the pedestal  3 . A central shaft  32  is disposed on the rotor pedestal  3 . The rotor  1  is sleeved on the central shaft  32 , and the rotor  1  rotates about the central shaft  32 . The rotor pedestal  3  is further provided with a drying bin for placing desiccant. The rotor pedestal  3  is further provided with a driving apparatus  33  for driving the rotor  1  to rotate, which is shown in  FIG. 12 . Preferably, the driving apparatus  33  is a motor. The motor includes a motor rotor and a motor stator. The motor stator is fixedly disposed on the central shaft  32 , and the motor rotor is connected to the rotor  1 . In addition, an inner surface of the motor rotor is opposite to an outer surface of the motor stator. 
     Further, as shown in  FIG. 12 , a first bearing  34  and a second bearing  35  are disposed between the central shaft  32  and the inner cylinder of the rotor  1  of the lidar for supporting the rotation of the rotor  1 . Specifically, the first bearing  34  is disposed between the rotor pedestal  3  of the lidar and the inner cylinder of the rotor  1 , and is connected to the central shaft  32 . The second bearing  35  is disposed on a top of the inner cylinder of the rotor  1  and is connected to the central shaft  32 . In this embodiment, a driving force is provided for the rotation of the rotor  1  through the driving apparatus  33 , and the rotation of rotating components are jointly supported by the first bearing  34  and the second bearing  35 , which reduce a friction coefficient during the motion of the rotor  1  and maintain the rotor  1  to be stable during rotation, thus ensuring rotation accuracy of the rotor, and overcome problems in the prior art such as a low scanning speed and poor rotation stability caused by the use of a single bearing to support the rotation of rotating components, so that the laser ranging achieves a best effect. In addition, a scanning speed can also be increased, thus improving operating efficiency of the lidar. 
     Further, as shown in  FIG. 4 , a plurality of first counterweight structures  1131  are disposed on the upper plane  113  of the rotor  1 . 
     As an exemplary solution, the first counterweight structure  1131  includes a plurality of counterweight slots and a plurality of counterweight holes. The plurality of counterweight slots are disposed at intervals, and the plurality of counterweight holes are symmetrically disposed on both sides of the counterweight slots. 
     As an exemplary solution, the counterweight slots include a first counterweight slot and a second counterweight slot. The first counterweight slot is separated from the second counterweight slot, and the first counterweight slot and the second counterweight slot have the same shape but unequal sizes. Preferably, in this embodiment, the first counterweight slot and the second counterweight slot are both waist-shaped structures, and the first counterweight slot and the second counterweight slot have the same slot depth. Center lines of the first counterweight slot and the second counterweight slot overlap, and an arc radius of the waist-shaped structure of the first counterweight slot is twice an arc radius of the waist-shaped structure of the second counterweight slot. 
     Preferably, there are  3  first counterweight slots and  3  second counterweight slots, and the first counterweight slots are separated from the second counterweight slots. 
     Two counterweight holes are symmetrically disposed on both sides of the counterweight slots. 
     Further, as shown in  FIG. 4 , a second counterweight structure  161  is disposed on the separator  16 . The second counterweight structure  161  is disposed close to the wall of the outer cylinder  11 . 
     As an exemplary solution, the second counterweight structure  161  is a round hole structure. 
     The first counterweight structure  1131  and the second counterweight structure  161  are disposed, so that the balance adjustment of the rotor  1  is implemented while reducing the weight of the rotor  1 . In addition, counterweight materials may be added to the first counterweight structure  1131  and the second counterweight structure  161  composed of slots or holes, to further implement balance adjustment of the rotor  1 . 
     Numbers, shapes, and arrangement positions of the first counterweight structures  1131  and the second counterweight structures  161  described above are merely an exemplary implementation and are not limited. In other optional embodiments, the first counterweight structures  1131  may also all be counterweight slot structures. The counterweight slot structures may be the same rectangular structure, different rectangular structures, or a combination of waist-shaped structures and rectangular structures. A specific shape of the first counterweight structure may be set according to process and counterweight under different circumstances. Similarly, the second counterweight structures  161  may also be the same rectangular structure or different rectangular structures or waist-shaped structures. A specific structure of the second counterweight structure may be set according to process and counterweight under different circumstances. 
     Embodiment 3 
     With reference to  FIG. 13  to  FIG. 17 , a laser emitting apparatus according to the present disclosure includes a laser emitter bracket  2011 , a transmitting circuit set  2012 , a transmitting circuit bracket  2013 , at least one laser emitter emitting board  2014 , and a plurality of flexible electrical connectors. 
     The laser emitter bracket  2011  is separated from the transmitting circuit bracket  2013 , the laser emitter emitting board  2014  is mounted to the laser emitter bracket  2011 , and at least one laser emitter  2015  is disposed on the laser emitter emitting board  2014 . 
     The transmitting circuit set  2012  is mounted to the transmitting circuit bracket  2013 , and the transmitting circuit set  2012  is connected to the laser emitter emitting board  2014  through the flexible electrical connector for supplying a driving signal and power to the laser emitter emitting board  2014 . 
     As shown in  FIG. 14  and  FIG. 15 , the laser emitter bracket  2011  includes a second bottom plate  20111  and a first side plate  20112 . The second bottom plate  20111  is connected to the first side plate  20112 , and the first side plate  20112  has a plurality of combs  201121  disposed side by side. Slots  201122  for mounting the laser emitter emitting board  2014  are formed between two adjacent combs  201121 . The laser emitter emitting board  2014  is inserted into the slot  201122 , and the laser emitter emitting board  2014  is connected to the first side plate  20112 . 
     The laser emitter emitting board  2014  is glued to the first side plate  20112 , for example, by adopting a hot melt adhesive. 
     The laser emitter bracket  2011  is, for example, T-shaped. The slots  201122  have the same width. Two adjacent slots  201122  have unequal lengths. The laser emitter emitting board  2014  is at a first preset angle to a horizontal plane. 
     A plurality of laser emitters  2015  are provided for one laser emitter emitting board  2014 . Light-emitting surfaces of the laser emitters  2015  are located on a focal plane of an optical exit system of the lidar. The plurality of laser emitter emitting boards  2014  are arranged at different heights on the first side plate  20112  in a vertical direction. 
     The plurality of the laser emitters  2015  are disposed at one end of the laser emitter emitting board  2014  at intervals. The plurality of laser emitters  2015  are arranged into an emitting array, and the plurality of laser emitters  2015  are disposed at different heights on the first side plate  20112  in the vertical direction. The laser emitters  2015  in the emitting array are non-uniformly distributed. As shown in  FIG. 14 , the laser emitters  2015  in the emitting array are sparsely distributed at two ends and densely distributed at a middle part in the vertical direction. Length directions of the slots  201122  are in a vertical direction of the first side plate  20112 . The vertical direction of the first side plate is consistent with a vertical direction of the lidar. 
     The laser emitter bracket  2011  is made of aluminum alloy or copper, for example. Preferably, the slots  201122  have different depths. After the laser emitter emitting board  2014  is fixed in the slot, a position of the light-emitting surface of the laser emitter  2015  on the laser emitter emitting board  2014  is determined. Preferably, the light-emitting surfaces of the laser emitters on the plurality of laser emitter emitting boards  2014  are located at different vertical heights of the focal plane of the optical exit system of the lidar. Those skilled in the art may easily understand that the heights of the plurality of laser emitter emitting boards  2014  may be the same or different, numbers of laser emitters on all of the emitting boards may be the same or different, and formed exit beams may be uniformly distributed or non-uniformly distributed. 
     As shown in  FIG. 17 , the transmitting circuit bracket  2013  is L-shaped, for example, and the transmitting circuit bracket  2013  includes a third bottom plate  20131  and a second side plate  20132 . The third bottom plate  20131  and the second side plate  20132  are connected, the second side plate  20132  has a first side surface  201321  and a second side surface  201322 , and the transmitting circuit set  2012  is mounted to a side of the first side surface  201321 . 
     The first side plate  20112  is at a second preset angle to the second side plate  20132 . 
     A plurality of assembling posts  20133  are provided on the first side surface  201321 , and the assembling posts  20133  are provided with first assembling holes  201331  for mounting the transmitting circuit set  2012 . 
     As shown in  FIG. 17 , two assembling posts  20133  are disposed at intervals on a top end of the first side surface  201321 , and three assembling posts  20133  are disposed at intervals on a bottom end of the first side surface  201321 . 
     As shown in  FIG. 13  and  FIG. 16 , the laser emitting apparatus further includes a first screw  20161 , a first nut  20162 , and a first washer  20163 . The first washer  20163  is sleeved on the first screw  20161 , and the first screw  20161  is mated with the first nut  20162 . 
     As shown in  FIG. 16 , the transmitting circuit set  2012  includes a transmitting motherboard  20121  and a plurality of transmitting daughterboards. The transmitting motherboard  20121  is separated from the plurality of transmitting daughterboards. 
     Adjacent transmitting daughterboards are connected through electrical connectors. The transmitting daughterboards include a first transmitting daughterboard  20122 , a second transmitting daughterboard  20123 , and a third transmitting daughterboard  20124 . The first transmitting daughterboard  20122  and the transmitting motherboard  20121  are connected through electrical connectors. Specifically, the electrical connectors may be flexible connection and/or rigid connection through docking of plugs and sockets. 
     As shown in  FIG. 16 , the first screw  20161  is threaded through the first assembling hole  201331 , the transmitting motherboard  20121 , the first transmitting daughterboard  20122 , the second transmitting daughterboard  20123 , and the third transmitting daughterboard  20124 , and is mated with the first nut  20162 . 
     As shown in  FIG. 16 , the transmitting motherboard  20121  is separated from the first transmitting daughterboard  20122  by the first washer  20163 . The first transmitting daughterboard  20122  is separated from the second transmitting daughterboard  20123  through the first washer  20163 . The second transmitting daughterboard  20123  is separated from the transmitting motherboard  20121  through the first washer  20163 . A spacing between the plurality of transmitting daughterboards and a spacing between the transmitting daughterboard and the transmitting motherboard  20121  may be adjusted through a thickness of the first washer  20163 . 
     The first washer  20163  is made of an insulator material such as plastics, ceramics, or the like. 
     The laser emitting apparatus further includes a plurality of second screws  20164 . With reference to  FIG. 13 ,  FIG. 16 , and  FIG. 17 , a corner of a side of the transmitting motherboard  20121  close to the laser emitter bracket  2011  is fixed to a corresponding assembling post  20133  through the second screw  20164 . A width of the third transmitting daughterboard  20124  is less than a width of the transmitting motherboard  20121 . Widths of the first transmitting daughterboard  20122  and the second transmitting daughterboard  20123  are located between the width of the transmitting motherboard  20121  and the width of the third transmitting daughterboard  20124 . The width of the transmitting motherboard  20121  is different from the widths of the plurality of transmitting daughterboards, helping give an assembling space and connect the transmitting circuit set  2012  to the laser emitter emitting board  2014  through the flexible electrical connector. 
     As shown in  FIG. 16  and  FIG. 17 , the second side surface  201322  is provided with a protrusion  20134 , which facilitates heat dissipation and adjustment of the counterweight of the lidar. 
     As shown in  FIG. 15 , a plurality of first mounting holes  201111  for fixing the laser emitter bracket  2011  are disposed on the second bottom plate  20111 , and the second bottom plate  20111  is fixed to the rotor of the lidar through the second screw  20164 . 
     As shown in  FIG. 15 , there are three first mounting holes  201111 . The first mounting holes  201111  are distributed at three corners of the second bottom plate  20111 . 
     As shown in  FIG. 15  and  FIG. 16 , a corner edge of the second bottom plate  20111  is provided with a first chamfer. The first chamfer is a straight chamfer, an arc chamfer, or a right-angle chamfer. 
     As shown in  FIG. 17  and  FIG. 18 , a plurality of second mounting holes  201311  for fixing the transmitting circuit bracket  2013  are disposed on the third bottom plate  20131 . The third bottom plate  20131  is fixed to the rotor of the lidar through the second screw  20164 . 
     There are three mounting holes on the third bottom plate  20131 . 
     A corner edge of the third bottom plate  20131  is provided with a second chamfer. 
     The second chamfer is a straight chamfer, an arc chamfer or a right-angle chamfer. 
     The laser emitter bracket  2011  is an integrally formed structure. 
     The transmitting circuit bracket  2013  is an integrally formed structure. 
     The laser emitter bracket  2011  and the transmitting circuit bracket  2013  are both made of any or a combination of copper, molybdenum, and aluminum. 
     The transmitting circuit set  2012  is provided with a plurality of driving circuits. The driving circuits are connected to the plurality of laser emitters  2015  to drive the plurality of laser emitters  2015  to emit light. 
     Each of the driving circuits drives one or more of the laser emitters  2015 . 
     The transmitting circuit set  2012  is further provided with a laser emitter control module. The laser emitter control module is configured to control the driving circuit to drive corresponding laser emitter  2015  to emit light. 
     In addition, the lengths of two adjacent slots  201122  may also be equal, and the laser emitters  5  in the emitting array may also be uniformly distributed. 
     The laser emitting apparatus according to the present disclosure adopts the laser emitter bracket and the transmitting circuit bracket to respectively mount the laser emitter emitting board and the transmitting circuit set, so that the space in the emitting chamber of the lidar is more flexible, and a volume of the laser emitter emitting board can be reduced, thus reducing a size and a weight of the system, which facilitates implementation of low costs and miniaturization of the lidar. 
     The laser emitter array of the laser emitting apparatus according to the present disclosure may be non-uniformly distributed. When the laser beam is non-uniformly distributed and is designed with a relatively small number of laser beams, a relatively high vertical angular resolution can be achieved, thus reducing costs and the volume. 
     Embodiment 4 
     Referring to  FIG. 13  and  FIG. 14 , a laser emitting apparatus includes a laser emitter bracket  2011 , a transmitting circuit set  2012 , a transmitting circuit bracket  2013 , at least one laser emitter emitting board  2014 , and a plurality of flexible electrical connectors. The laser emitter bracket  2011  is separated from the transmitting circuit bracket  2013 . The laser emitter emitting board  2014  is mounted to the laser emitter bracket  2011 , and at least one laser emitter  2015  is disposed on the laser emitter emitting board  2014 . The transmitting circuit set  2012  is mounted to the transmitting circuit bracket  2013 , and the transmitting circuit set  2012  is connected to the laser emitter emitting board  2014  through the flexible electrical connectors. 
     As shown in  FIG. 18 , the laser emitter bracket  2011  includes a second bottom plate  20111  and a first side plate  20112 . The second bottom plate  20111  is connected to the first side plate  20112 , and the first side plate  20112  has a plurality of combs  201121  disposed side by side. Slots  201122  for mounting the laser emitter emitting board  2014  are formed between two adjacent combs  201121 . The laser emitter emitting board  2014  is inserted into the slot  201122 , and the laser emitter emitting board  2014  is connected to the first side plate  20112 . 
     The laser emitter emitting board  2014  is glued to the first side plate  20112 . 
     The laser emitter bracket  2011  is L-shaped. The slots  201122  have the same width. Two adjacent slots  201122  have an equal length. The laser emitter emitting board  2014  is at a first preset angle to a horizontal plane. 
     A plurality of laser emitters  2015  are provided for one laser emitter emitting board  2014 . Light-emitting surfaces of the laser emitters  2015  are located on a focal plane of an optical exit system of the lidar. The plurality of laser emitter emitting boards  2014  are arranged at different heights on the first side plate  20112  in a vertical direction. 
     As shown in  FIG. 19 , the plurality of laser emitters  2015  are disposed at one end of the laser emitter emitting board  2014  at intervals. The plurality of laser emitters  2015  are arranged into an emitting array, and the plurality of laser emitters  2015  are disposed at different heights on the first side plate  20112  in a vertical direction. 
     Length directions of the slots  201122  are in a horizontal direction of the first side plate  20112 . A width direction of the first side plate is consistent with a horizontal direction of the lidar. 
     As shown in  FIG. 19 , the plurality of laser emitter emitting boards  2014  are disposed in parallel at intervals, the plurality of laser emitters  2015  are oppositely disposed on two opposite side surfaces of the laser emitter emitting board  2014 , and the plurality of laser emitters  2015  are distributed at one end edge of the laser emitter emitting board  2014  facing an optical exit system of the lidar. 
     As shown in  FIG. 19 , distances between adjacent laser emitter emitting boards  2014  are unequal, and the laser emitters  2015  in the emitting array are sparsely distributed at two ends and densely distributed at a middle part in a vertical direction. The laser emitter emitting boards  2014  are parallel to the horizontal plane, and the adjacent laser emitter emitting boards  2014  correspond to each other in the vertical direction. 
     Same as Embodiment 3, as shown in  FIG. 16  and  FIG. 17 , the transmitting circuit bracket  2013  is L-shaped, and the transmitting circuit bracket  2013  includes a third bottom plate  20131  and a second side plate  20132 . The third bottom plate  20131  is connected to the second side plate  20132 , and the second side plate  20132  has a first side surface  201321  and a second side surface  201322 . The transmitting circuit set is mounted to a side of the first side surface  201321 . 
     The first side plate  20112  is at a second preset angle to the second side plate  20132 . A plurality of assembling posts  20133  are provided on the first side surface  201321 , and the assembling posts  20133  are provided with first assembling holes  201311  for mounting the transmitting circuit set  2012 . Two assembling posts  20133  are disposed at intervals on a top end of the first side surface  201321 , and three assembling posts  20133  are disposed at intervals on a bottom end of the first side surface  201321 . 
     The laser emitting apparatus further includes a first screw  20161 , a first nut  20162 , and a first washer  20163 . The first washer  20163  is sleeved on the first screw  20161 , and the first screw  20161  is mated with the first nut  20162 . 
     The transmitting circuit set  2012  includes a transmitting motherboard  20121  and a plurality of transmitting daughterboards. The transmitting motherboard  20121  is separated from the plurality of transmitting daughterboards. 
     The adjacent transmitting daughterboards are connected through the flexible electrical connectors. The transmitting daughterboards include a first transmitting daughterboard  20122 , a second transmitting daughterboard  20123 , and a third transmitting daughterboard  20124 . The first transmitting daughterboard  20122  and the transmitting motherboard  20121  are connected through the flexible electrical connectors. 
     The first screw  20161  is threaded through the first assembling holes  201311 , the transmitting motherboard  20121 , the first transmitting daughterboard  20122 , the second transmitting daughterboard  20123 , and the third transmitting daughterboard  20124 , and is mated with the first nut  20162 . 
     The transmitting motherboard  20121  is separated from the first transmitting daughterboard  20122  through the first washer  20163 . The first transmitting daughterboard  20122  is separated from the second transmitting daughterboard  20123  through the first washer  20163 . The second transmitting daughterboard  20123  is separated from the transmitting motherboard  20121  through the first washer  20163 . 
     A spacing between the plurality of transmitting daughterboards and a spacing between the transmitting daughterboard and the transmitting motherboard  20121  may be adjusted through a thickness of the first washer  20163 . The first washer  20163  is made of an insulator material such as plastics, ceramics, or the like. 
     The laser emitting apparatus further includes a plurality of second screws  20164 . A corner of a side of the transmitting motherboard  20121  close to the laser emitter bracket  2011  is fixed to a corresponding assembling post  20133  through the second screw  20164 . A width of the third transmitting daughterboard  20124  is less than a width of the transmitting motherboard  20121 . Widths of the first transmitting daughterboard  20122  and the second transmitting daughterboard  20123  are located between the width of the transmitting motherboard  20121  and the width of the third transmitting daughterboard  20124 . The width of the transmitting motherboard  20121  is different from the widths of the plurality of transmitting daughterboards, helping give an assembling space and connect the transmitting circuit set  2012  to the laser emitter emitting board  2014  through the flexible electrical connector and/or a rigid electrical connector. Specifically, the rigid electrical connector is a plug and socket. 
     The second side surface  201322  is provided with a protrusion  20134 , which facilitates heat dissipation and adjustment of the counterweight of the lidar. A plurality of first mounting holes  201111  for fixing positions of the laser emitter bracket  2011  are disposed on the second bottom plate  20111 , and the second bottom plate  20111  is fixed to the rotor of the lidar through the second screw  20164 . There are three mounting holes. The first mounting holes  201111  are distributed at three corners of the second bottom plate  20111 . 
     The second bottom plate  20111  is provided with a first chamfer. The first chamfer is a straight chamfer, an arc chamfer, or a right-angle chamfer. 
     A plurality of second mounting holes  201311  for fixing positions of the transmitting circuit bracket  2013  are disposed on the third bottom plate  20131 . The third bottom plate  20131  is fixed to the rotor of the lidar through the second screw  20164 . There are three mounting holes on the third bottom plate  20131 . 
     The third bottom plate  20131  is provided with a second chamfer. The second chamfer is an arc chamfer. 
     The laser emitter bracket  2011  is an integrally formed structure. The transmitting circuit bracket  2013  is an integrally formed structure. The laser emitter bracket  2011  and the transmitting circuit bracket  2013  are both made of any or a combination of copper, molybdenum, and aluminum. 
     The transmitting circuit set  2012  is provided with a plurality of driving circuits. The driving circuits are connected to the plurality of laser emitters  2015  to drive the plurality of laser emitters  2015  to emit light. 
     Each of the driving circuits drives one or more of the laser emitters  2015 . The transmitting circuit set  2012  is further provided with a laser emitter control module. The laser emitter control module is configured to control the driving circuit to drive corresponding laser emitter  2015  to emit light. 
     In addition, lengths of two adjacent slots  201122  may also be unequal. 
     Embodiment 5 
     As shown in  FIG. 18 , a difference between this embodiment and Embodiment 4 is that the plurality of laser emitter emitting boards  2014  are disposed in parallel at intervals, and the laser emitters  2015  are oppositely disposed on the laser emitter emitting board  2014 . Distances between adjacent laser emitter emitting boards  2014  are equal. The laser emitter emitting boards  2014  are parallel to the horizontal plane, and the adjacent laser emitter emitting boards  2014  correspond to each other in the vertical direction. 
     Embodiment 6 
     As shown in  FIG. 21  and  FIG. 22 , a receiving system for a lidar includes a receiving lens set  301 , a second mirror set  302 , and a receiving apparatus  303 . 
     The receiving lens set  301  is configured to converge light reflected from a target object. 
     The second mirror set  302  is configured to change a path of a beam and cause the reflected light to be incident on the receiving apparatus  303 . 
     The receiving apparatus  303  includes a light filter  3031 , a receiving device  3032 , a receiving circuit bracket  3033 , and a plurality of receiving circuit boards  3034  (see  FIG. 23 ). The receiving device  3032  and the receiving circuit boards  3034  are mounted to the receiving circuit bracket  3033 , and the light filter  3031  is disposed on a side of the receiving device  3032  facing the second mirror set  302  for filtering stray light. Rays of light of various wavelengths can enter the receiving lens set  301  and be reflected to the receiving apparatus  303  through the second mirror set  302 . A ray of light with a specific wavelength in the incident rays of light represents useful reflected light, that is, a ray of light with a wavelength corresponding to a wavelength of the laser emitter  2015  is signal light, and rays of light with other wavelengths is interference light or stray light. Therefore, the light filter  3031  may cause the ray of light with the wavelength corresponding to the wavelength of the laser emitter  2015  to pass through, and the rays of light with other wavelengths to be blocked and filtered out, thereby increasing a signal-to-noise ratio of the lidar and improving ranging performance. The receiving device  3032  is configured to obtain distance information and to convert a received optical signal into an electrical signal. The receiving circuit board  3034  is configured to process the distance information obtained by the receiving device  3032 . 
     With reference to  FIG. 23  to  FIG. 25 , the receiving device  3032  includes a substrate  30321 , an APD array detector (not shown in the figure), and a protective shell  30323 . The substrate  30321  is fixed to the receiving circuit bracket  3033 . The APD array detector is disposed on a side surface of the substrate  30321 . The protective shell  30323  is covered on the APD array detector, and the protective shell  30323  is mounted on the substrate  30321 . 
     With reference to  FIG. 23  to  FIG. 25 , the light filter  3031  is attached and mounted on a side surface of the protective shell  30323  away from the APD array detector. 
     The APD array detector is a planar-array APD detector, which consists of planar-array avalanche photodiodes arranged in an M×N array, such as 4×4, 4×8, 8×8, or the like, where M≥2 and N≥2. An optical signal is converted into an electrical signal through an avalanche effect of the photodiodes. Specifically, the M×N arrangement depends on the arrangement of laser emitters in the lidar. 
     The protective shell  30323  is made of metal. 
     The receiving apparatus  303  further includes a flexible electrical connector. Two adjacent receiving circuit boards  3034  are connected through the flexible electrical connector. 
     With reference to  FIG. 23 ,  FIG. 26 , and  FIG. 27 , the receiving circuit bracket  3033  includes a fourth bottom plate  30331  and a third side plate  30332 . The fourth bottom plate  30331  is connected to the third side plate  30332 , and the third side plate  30332  has a third side surface  303321  and a fourth side surface  303322 . The plurality of receiving circuit boards  3034  are sequentially mounted on the third side surface  303321  at intervals. The receiving device  3032  is mounted on the fourth side surface  303322 . 
     As shown in  FIG. 26  and  FIG. 27 , the third side surface  303321  is provided with a second groove  303323 , and the second groove  303323  is provided with a second through hole  303324 . The second through hole  303324  penetrates through a bottom surface of the second groove  303323  and the fourth side surface  303322 . 
     The second groove  303323  is configured to not only reduce a weight of the bracket, but also facilitate assembly of the receiving circuit board  3034 , giving a sufficient assembling space for elements such as a chip of the circuit board. 
     The second through hole  303324  is configured to not only reduce the weight of the bracket, but also facilitate assembly of the substrate  30321 , giving an assembling space for elements such as a chip of the substrate  30321 . 
     As shown in  FIG. 23 , the receiving apparatus  303  further includes a third screw  3035 , a second nut  3036 , and a second washer  3037 . The second washer  3037  is sleeved on the third screw  3035 , and the third screw  3035  is mated with the second nut  3036 . 
     With reference to  FIG. 23 ,  FIG. 26 , and  FIG. 27 , second assembling holes  303326  are correspondingly provided on corners of the substrate  30321 , the third side plate  30332 , and the receiving circuit board  3034 . 
     The third screw  3035  is sequentially threaded through the substrate  30321 , the third side plate  30332 , and the receiving circuit board  3034 , and is mated with the second nut  3036 . 
     As shown in  FIG. 23 , the receiving circuit board  3034  includes a first circuit board  30341 , a second circuit board  30342 , and a third circuit board  30343 . 
     The first circuit board  30341  is separated from the second circuit board  30342  through the second washer  3037 . The second circuit board  30342  is separated from the third circuit board  30343  through the second washer  3037 . A spacing between the plurality of receiving circuit board  3034  may be adjusted through a thickness of the second washer  3037 . The second washer  3037  is made of an insulator material. 
     As shown in  FIG. 26  and  FIG. 27 , the third side plate  30332  is vertically connected to the fourth bottom plate  30331 , and a distance between a projection of the fourth side surface  303322  on the fourth bottom plate  30331  and a plate edge of the fourth bottom plate  30331  away from the fourth side surface  303322  is equal to a thickness of the substrate  30321 . 
     As shown in  FIG. 27 , the fourth side surface  303322  is further provided with a positioning plate  303325  in a height direction of the third side plate  30332  for quickly determining a mounting position for the substrate  30321 . 
     As shown in  FIG. 26 , a protruding plate  303311  extends from an end of the fourth bottom plate  30331  away from the third side surface  303321 . The protruding plate  303311  is provided with a plurality of third mounting holes  303313  for fixing the receiving circuit bracket  3033 . 
     As shown in  FIG. 27 , an assembling lug  303312  further extends from the end of the fourth bottom plate  30331  away from the third side plate  30332 . The assembling lug  303312  is provided with a third mounting hole  303313  for fixing the receiving circuit bracket  3033 . 
     As shown in  FIG. 23 , the receiving apparatus  303  further includes a plurality of fourth screws  3038 . The fourth screws  3038  is threaded through the third mounting holes  303313  to fix the receiving circuit bracket  3033  to the rotor of the lidar. 
     The receiving circuit bracket  3033  is an integrally formed structure. The receiving circuit bracket  3033  is made of any or a combination of copper, molybdenum, and aluminum. 
     As shown in  FIG. 21 , the second mirror set  302  includes a third mirror  3021  and a fourth mirror  3022 . The third mirror  3021  is opposite to the fourth mirror  3022 . 
     The light reflected from the target object converged by the receiving lens set  301  is for a receiving field angle of the APD array detector. 
     Fourth bottom plates  30331  are all provided with chamfers. The chamfer is a straight chamfer, an arc chamfer, or a right-angle chamfer. 
     An avalanche photodiode (APD) array detector, that is, an avalanche photodiode detector, is integrated by a plurality of independent APD unit detectors, which has a compact structure, a small volume, and a light weight. The APD detector is an APD unit detector, which can implement scanning-free laser detection and three-dimensional imaging with a single pulse. The APD array detector can directly obtain three-dimensional information, and has a faster imaging speed and a simple system structure. The detection system performs multi-channel parallel processing on laser echo signals received by each unit of the array detector, thus implementing linear array imaging. 
     Embodiment 7 
     A difference between this embodiment and Embodiment 6 is that the APD array detector is a linear-array APD detector, which consists of n (such as 1, 4, 16, 32, or the like) avalanche photodiodes, where n≥1, and converts an optical signal into an electrical signal through an avalanche effect of the photodiodes. Specifically, n depends on a way of laser emitter arrangement of the lidar. 
     Embodiment 8 
     A difference between this embodiment and Embodiment 6 is that 
     the receiving device includes a substrate and one APD detector, the substrate is fixed to the receiving circuit bracket, and the APD detector is disposed on a side surface of the substrate. The receiving device further includes a protective shell, where the protective shell is covered on the APD detector and is mounted to the substrate. 
     Embodiment 9 
     With reference to  FIG. 28 ,  FIG. 29 , and  FIG. 30 , a wireless power transmission apparatus includes a wireless power emitting assembly and a wireless power receiving assembly. The wireless power emitting assembly is separated from and opposite to the wireless power receiving assembly. The wireless power emitting assembly includes a transmitting coil  406  and a transmitting circuit board  407 . The transmitting coil  406  is connected to the transmitting circuit board  407 . 
     The wireless power receiving assembly includes a receiving coil  401 , a magnetic isolation board  402 , and two receiving circuit boards  403 . The receiving coil  401  is opposite to the transmitting coil  406 . The magnetic isolation board  402  is disposed on a side of the receiving coil  401  away from the transmitting coil  406 , and the magnetic isolation board  402  covers the receiving coil  401 . The receiving coil  401  is connected to the receiving circuit boards  403 . 
     The receiving circuit board  403  includes a fourth circuit board  4031  and a fifth circuit board  4032 . The fourth circuit board  4031  is separated from and opposite to the fifth circuit board  4032 . The fifth circuit board  4032  is connected to the magnetic isolation board  402 , and the magnetic isolation board  402  is disposed on a side of the fifth circuit board  4032  facing the fourth circuit board  4031 . A plurality of copper post tubes  404  are provided between the fourth circuit board  4031  and the fifth circuit board  4032  for adjusting a spacing between the fourth circuit board  4031  and the fifth circuit board  4032 . 
     The wireless power transmission apparatus further includes a plurality of fifth screws  4051  and third nuts  4052  mated with the fifth screws  4051 . The fourth circuit board  4031  is connected to the fifth circuit board  4032  through the fifth screws  4051  and the third nuts  4052 . The fifth screws  4051  are in a one-to-one correspondence with the copper post tubes  404 . The fifth screws  4051  is sequentially threaded through the fifth circuit board  4032 , the copper post tubes  404 , and the fourth circuit board  4031 , and are mated with the third nuts  4052 . The fourth circuit board  4031  is provided with a first assembling hole for the fifth screw  4051  to be threaded through. The copper post tube  404  is provided with a plug and socket portion mated with the first assembling hole, and the copper post tube  404  is fixed to the fourth circuit board  4031  through the insertion portion, which is convenient to assemble. 
     The fourth circuit board  4031  is a circular circuit board, and a fourth through hole  40311  is provided at a central position on the fourth circuit board  4031 . The fourth through hole  40311  penetrates through two opposite side surfaces of the fourth circuit board  4031 . The fourth through hole  40311  is a circular through hole. The fourth circuit board  4031  is further provided with a first perforation  40312  and a second perforation  40313 . The fourth circuit board  4031  is connected to the transmitting circuit set of the lidar, and the fourth circuit board  4031  is connected to the receiving circuit set of the lidar. 
     The fourth circuit board  4031  is provided with a plurality of first mounting holes at intervals in a circumferential direction. The fourth circuit board  4031  is fixed to the rotor of the lidar by threading the screw through the first mounting hole. 
     The fifth circuit board  4032  is a special-shaped circuit board. The fifth circuit board  4032  includes a first connecting portion  40321  and a second connecting portion  40322 . The first connecting portion  40321  is circular, the second connecting portion  40322  is fan-shaped, and the second connecting portion  40322  is attached to a part of an outer edge of the first connecting portion  40321 . 
     An unfilled corner is further provided on a side of the outer edge of the second connecting portion  40322  to facilitate assembly. A shape of the magnetic isolation board  402  is similar to a shape of the fifth circuit board  4032 , and outline dimensions of the magnetic isolation board  402  are less than outline dimensions of the fifth circuit board  4032 . 
     The magnetic isolation board  402  includes a third connecting portion  4021  and a fourth connecting portion  4022 . The third connecting portion  4021  is circular, the fourth connecting portion  4022  is fan-shaped, and the fourth connecting portion  4022  is attached to a part of an outer edge of the third connecting portion  4021 . A thickness of the fourth connecting portion  4022  is less than a thickness of the third connecting portion  4021 . The second connecting portion  40322  is provided with a plurality of glue injection holes  40323 , and the magnetic isolation board  402  is glued to the fifth circuit board  4032 . 
     An annular boss  24  is provided on a side of the magnetic isolation board  402  facing the fifth circuit board  4032 , and the receiving coil  401  is attached to the annular boss  24 . 
     The first connecting portion is provided with a fifth through hole  40324  opposite to the fourth through hole  40311 , and a size of the fifth through hole  40324  is greater than that of the fourth through hole  40311 . 
     The magnetic isolation board  402  is provided with a third through hole  4023  opposite to the fourth through hole  40311 . 
     The fourth through hole  40311 , the fifth through hole  40324 , and the third through hole  4023  are coaxially disposed. An orthographic projection of the receiving coil  401  toward the magnetic isolation board  402  is located in the magnetic isolation board  402 . The magnetic isolation board  402  is a ferrite magnet, an amorphous magnet, or a soft magnet for electromagnetically shielding the rotor of the lidar. 
     The transmitting coil  406  and the receiving coil  401  are respectively spirally arranged on the same plane. A fourth through hole is provided at a central position on the transmitting coil  406 , and a fifth through hole is provided at a central position on the receiving coil  401 . The fourth through hole and the fifth through hole are coaxially disposed. 
     An operating principle of the wireless power transmission apparatus is as follows 
     The wireless power transmission apparatus uses an electromagnetic induction principle, which means that a conductor placed in a changing magnetic flux generates an electromotive force. The electromotive force is referred to as an inductive electromotive force or an induced electromotive force. If the conductor is closed into a loop, the electromotive force drives electrons to flow to form an induced current. When a transmitting coil is powered on, an electromagnetic transmitting coil, which acts as an electromagnetic emitting end, generates a magnetic field. The generated magnetic field causes the receiving coil to generate a current to supply power to inside of the rotor. 
     Second Aspect 
     A second aspect of the present disclosure relates to a laser emitter or a laser emitter module, which is described in detail below with reference to the accompanying drawings. 
     Lidar is a common name of active detection sensor devices though lasers. An operating principle of a lidar is substantially as follows. An emitter of the lidar emits a laser, and the laser beam returns to a laser receiver through diffuse reflection after encountering an object. A radar module can calculate a distance between the emitter and the object merely by multiplying a time interval between sending and receiving of signals and the speed of light and then dividing the product by 2. In terms of a number of laser beams, there are usually a single-beam lidar, a 4-beam lidar, an 8/16/32/64-beam lidar, and the like. One or more laser beams are emitted at different angles in a vertical direction and scanned in a horizontal direction, to implement detection of a three-dimensional profile of a target region. A plurality of measurement channels (laser beams) are equivalent to scanning planes at a plurality of angles. Therefore, more laser beams in a vertical field of view lead to a higher angular resolution in the vertical direction and a higher density of laser-point cloud. FIG. 31A schematically shows an example of a lidar. The lidar is a 16-beam lidar, that is, totally 16 laser beams: L1, L2, . . . , L15, L16 may be emitted in a vertical plane in the figure for detecting surroundings. During detection, the lidar may rotate along a vertical axis thereof. During the rotation, channels of the lidar sequentially emit laser beams and detect the laser beams at a specified time interval (for example, 1 microsecond) to complete laser beam scanning once in a perpendicular field of view, and then perform next laser beam scanning in the perpendicular field of view at an interval of a specified angle (for example, 0.1 degrees or 0.2 degrees) in a horizontal field of view. In this way, the surroundings can be sensed merely by forming a point cloud through a plurality of times of detection during the rotation. 
     Most semiconductor laser emitter chips currently applied to a mechanical lidar are edge-emitting. A light-emitting surface of the edge-emitting laser emitter has a fast axis direction and a slow axis direction, which is schematically shown in  FIG. 31B . A size of the edge-emitting laser emitter in the slow axis direction is relatively large, for example, on the order of 100 μm, and a size in the fast axis direction is relatively small, for example, on the order of 10 μm. In addition,  FIG. 31B  also schematically shows a negative electrode N of the laser emitter chip. A positive electrode P is located on a lower surface opposite to the negative electrode N, for example. 
       FIG. 31C  schematically shows a schematic diagram of mounting of a laser emitter chip in a mechanical lidar. With reference to  FIG. 31A ,  FIG. 31B , and  FIG. 31C , a circuit board in  FIG. 31C  is disposed in the lidar in a vertical direction in  FIG. 31A , and a plurality of edge-emitting laser emitter chips shown in  FIG. 31B  are disposed thereon in a vertical direction (the vertical direction in  FIG. 31A ) of a focal plane of an optical exit system of the lidar. The laser emitter chips emit laser beams from the light-emitting surface, and the laser beams aim at the exit optical system. Since the slow axis direction of the light-emitting surface is parallel to the electrode, and the electrode of the laser emitter chip is directly attached to the circuit board during conventional application, the slow axis direction of the light-emitting surface is parallel to the circuit board (which is shown in  FIG. 31C ). In  FIG. 31C , a plurality of edge-emitting laser emitter chips are disposed in a vertical direction of a lidar. Therefore, the slow axis direction (a vertical dashed line in  FIG. 31C ) of the light-emitting surface of the laser emitter chips in  FIG. 31C  is the vertical direction in  FIG. 31A , and the fast axis direction of the light-emitting surface is perpendicular to a direction of a paper surface. For the lidar, if a limit of an angular resolution in the vertical direction needs to be increased, a size of the light-emitting surface in the vertical direction needs to be minimized. In the structure shown in  FIG. 31C , the plurality of laser emitter chips need to be disposed in the vertical direction of the lidar, and the slow axis direction of the laser emitter chips needs to be in the vertical direction in the figure. However, the slow axis size of the edge-emitting laser emitter is relatively large (on the order of 100 μm). Therefore, the laser emitter chips cannot be arranged more densely within a limited vertical dimension range of the focal plane, impeding an increase in the limit of the angular resolution in the vertical direction. Based on the above situation, the prior art provides a solution of horizontally placing the circuit board, which is shown in  FIG. 32 . 
     In the technical solution of  FIG. 32 , a circuit board is placed horizontally, and a laser emitter chip is directly attached to the circuit board. The technical solution has the following disadvantages. 
     First, a laser emitter with a different vertical height (located at a focal plane of an emitting lens) serves each different vertical angle of the lidar. In this case, a corresponding number of circuit boards need to be horizontally placed (for example, 64 circuit boards for a 64-beam lidar) and staggered in a vertical direction. Therefore, within a specified size, a limit of an angular resolution of the lidar in a vertical direction is greatly restricted by a thickness of the circuit board, a height of a component on the circuit board, and the like. 
     Secondly, in order to ensure consistency of vertical angles of the lidar, a position of a circuit board carrying each laser emitter needs to be accurately fixed, which is cumbersome and complicated. 
     Therefore, laser emitters and lidars that can increase the angular resolution in the vertical direction are continuously required in the prior art. 
     A second aspect of the present disclosure relates to a laser emitter  510 , which is shown in  FIG. 33A ,  FIG. 33B ,  FIG. 33C , and  FIG. 33D . Detailed description is given below with reference to  FIG. 33A  and  FIG. 33B .  FIG. 33A  is a three-dimensional diagram of a laser emitter  510  viewed from a front side,  FIG. 33B  is a three-dimensional diagram of the laser emitter  510  viewed from a rear side, and  FIG. 33C  and  FIG. 33D  are respectively renderings of  FIG. 33A  and  FIG. 33B , to show a specific structure of the laser emitter more clearly. 
     As shown in  FIG. 33A  and  FIG. 33B , the laser emitter  510  includes a base  511 , a laser emitter chip  512 , and a laser beam shaping element  513 . The laser emitter chip  512  is disposed on the base  511 , and the laser emitter chip  512  has a light-emitting surface  5121 . After driving of a voltage, a laser beam is emitted from the light-emitting surface  5121 . The laser beam shaping element  513  is opposite to the light-emitting surface  5121 . In order to accurately position the laser beam shaping element  513  on the base, a positioning portion  5111  is formed on the base  511  for positioning the laser beam shaping element  513 .  FIG. 33B  and  FIG. 33D  show the positioning portion  5111  more clearly. 
     The operating principle and method of the laser emitter  510  are as follows. The base  511  provides support and positioning for other optoelectronic components of the laser emitter  510 . After being driven by the voltage, the laser emitter chip  512  emits a laser beam from the light-emitting surface  5121  thereof. Since the light-emitting surface  5121  is opposite to the laser beam shaping element  513 , the emitted laser beam is optically shaped and modulated by the laser beam shaping element  513  to change some optical parameters and properties of the emitted laser beam, and then continues to be emitted. Those skilled in the art can understand that an appropriate laser beam shaping element  513  and functions to be implemented by the laser beam shaping element may be selected according to different circumstances. For example, the laser beam shaping element  513  may compress, in some direction, the laser beam emitted from the light-emitting surface  5121  to reduce an angle of divergence in the direction. Alternatively, the laser beam shaping element  513  may adjust a diameter of the laser beam emitted from the light-emitting surface  5121 . The laser beam shaping element  513  may include one or more of an optical fiber, a cylindrical lens, a D lens, or an aspherical lens. The present disclosure is not limited to the specific type of the laser beam shaping element  513  and the shaping and the modulation implemented by the laser beam shaping element. All fall within the scope of the present disclosure. Preferably, the positioning portion  5111  is disposed in such a way that a center of the laser beam shaping element  513  is at the same height as a center of the light-emitting surface  5121  of the laser emitter chip  512 , facilitating adjustment to optical parameters of the laser beam through the laser beam shaping element  513 . 
     According to an exemplary embodiment of the present disclosure, the laser emitter chip  512  is an edge-emitting laser emitter chip, such as an edge-emitting distributed Bragg reflector (DBR) laser emitter chip, an edge-emitting distributed feedback (DFB) laser emitter chip, or the like. The light-emitting surface of the edge-emitting laser emitter has a slow axis direction and a fast axis direction.  FIG. 33A  schematically shows a fast axis direction and a slow axis direction of a light-emitting surface of a laser emitter chip  512 . A size of the light-emitting surface of the edge-emitting laser emitter in the slow axis direction is usually relatively large, and a size in the fast axis direction (that is, a size in a thickness direction of the laser emitter chip  512  in the figure) is usually relatively small. Angles of divergence of laser beams emitted by the edge-emitting laser emitters in the fast axis direction and the slow axis direction are usually different. Generally, the angle of divergence in the slow axis direction is relatively small, and the angle of divergence in the fast axis direction is relatively large.  FIG. 34A  shows an angle of divergence θ of a laser beam emitted by a laser emitter chip in a slow axis direction and an angle of divergence α in a fast axis direction. It may be clearly seen that the angle of divergence α in the fast axis direction is significantly larger than the angle of divergence θ in the slow axis direction. Those skilled in the art may easily understand that the angle of divergences α and θ shown in  FIG. 34A  are merely illustrative and do not mean that an actual angle of divergence of the laser emitter chip is so large. According to an embodiment, the angle of divergence θ in the slow axis direction is, for example, about ten degrees, and the angle of divergence α in the fast axis direction is, for example, about 30 degrees. 
     The laser emitter chip  512  is attached to the base  511 , for example, and is disposed in such a way that the light-emitting surface  5121  is perpendicular to a surface to which the laser emitter chip is attached and parallel to a direction in which the positioning portion  5111  extends, which is shown in  FIG. 33A  and  FIG. 33B . The laser emitter chip  512  and the laser beam shaping element  513  are disposed on the base  511  in such a way that the slow axis direction of the light-emitting surface  5121  is parallel to a direction in which the laser beam shaping element  513  extends, thereby reducing a height of the light-emitting surface of the laser emitter  510 , that is, reducing the size of the light-emitting surface in the vertical direction in  FIG. 33 . The laser beam shaping element  513  is, for example, a fast axis compression element, which can compress the angle of divergence of the laser emitted from the light-emitting surface  5121 , in the fast axis direction, so that after the emitted laser beam passes through the laser beam shaping element  513 , the angle of divergence in the fast axis direction is smaller, and a convergence degree is higher.  FIG. 34B  and  FIG. 34C  show a situation in which an angle of divergence α of a laser beam emitted by a light-emitting surface  5121  of a laser emitter chip  512  in a fast axis direction decreases after the laser beam passes through a laser beam shaping element  513 .  FIG. 34B  shows a situation in which a D lens serves as the laser beam shaping element  513 , and  FIG. 34C  shows a situation in which an optical fiber serves as the laser beam shaping element  513 . A dashed line shows an uncompressed light path, and a solid line corresponding to the dashed line is a light path compressed by the fast axis. As shown in the figure, after the laser beam passes through the D lens or the optical fiber, the angle of divergence α of the laser beam in the fast axis direction is significantly reduced. 
     In addition, the laser emitter chip and the laser beam shaping element  513  shown in  FIG. 34B  and  FIG. 34C  are spaced apart from each other by a specified distance, which is merely for illustrative purposes and does not limit the protection scope of the present disclosure. The laser emitter chip and the laser beam shaping element may also be closely adjacent. According to an embodiment of the present disclosure, after the laser beam passes through the laser beam shaping element  513 , the angle of divergence α of the laser beam in the fast axis direction is compressed to be equivalent to the angle of divergence θ in the slow axis direction, for example, reduced from 30 degrees to, for example, ten degrees. 
     According to an exemplary embodiment of the present disclosure, the laser beam shaping element  513  may include one or more of an optical fiber, a cylindrical lens, a D lens, or an aspherical lens. The shaping and the modulation of the laser beam emitted from the light-emitting surface  5121  can be implemented through all of the various examples of the laser beam shaping element  513  listed above. For example, the angle of divergence of the laser beam in the fast axis direction is most frequently compressed through a cylindrical lens. 
     According to an exemplary embodiment of the present disclosure, the positioning portion  5111  includes one or more of a V-shaped groove, a U-shaped groove, and a step for accurately positioning the laser beam shaping element  513 . The positioning portion  5111  is, for example, a microstructure located near an end of the base. For example, a microstructure such as a V-shaped groove or grooves of other shapes or a step on the order of μm may be processed at a front end on a silicon base through an etching process. The microstructure is used for accurate positioning of the laser beam shaping element  513 . In the case of the V-shaped groove, the laser beam shaping element  513  may be directly embedded in the V-shaped groove for positioning. In the case of the step, the laser beam shaping element  513  may be positioned close to the step. Those skilled in the art easily understand that, after being accurately positioned, the laser beam shaping element  513  may be fixed in place through other additional means, for example, fixed to the base  511  through an adhesive. 
       FIG. 33A  and  FIG. 33B  show that a positioning portion  5111  includes a V-shaped groove, which is, for example, at a position close to an end of a base  511 . The laser beam shaping element  513  is an optical fiber clamped in the V-shaped groove.  FIG. 33A  and  FIG. 33B  show that the positioning portion  5111  further includes a step. The combination of the V-shaped groove and the step facilitates accurate positioning of the laser beam shaping element  513  relative to the light-emitting surface  5121  of the laser emitter chip  512 , and facilitates accurate modulation and shaping of the laser beam emitted from the light-emitting surface  5121 . Those skilled in the art understand that either the V-shaped groove or the step can serve as a positioning portion alone to implement the accurate positioning of the laser emitter chip  5121  relative to the laser beam shaping element. All fall within the protection scope of the present disclosure. 
     It is to be noted that the positioning portion stated in the present disclosure refers to a part or an element that facilitates the positioning of the laser beam shaping element, which does not indicate that the laser beam shaping element can be positioned through the positioning portion alone without other components. This is easily understood for those skilled in the art. For example, in the embodiments of  FIG. 33A  and  FIG. 33B , in addition to the positioning portion  5111 , an adhesive or the like may also be used to enhance the positioning effect. Details are not described herein again. 
     The semiconductor laser emitter structure with a structure accurately positioned shown in  FIG. 33A ,  FIG. 33B ,  FIG. 33C , and  FIG. 33D  can conveniently modulate the beam of the laser emitter chip and is convenient to mount. 
       FIG. 35A  and  FIG. 35B  show a laser emitter  510  according to another embodiment of the present disclosure, in which a positioning portion  5111  includes a step, and a laser beam shaping element  513  is a D lens positioned against the step. A laser beam emitted from a light-emitting surface  5121  of a laser emitter chip  512  enters one side of a plane of the D lens, and is emitted at a smaller angle of divergence in a fast axis direction from the other side. Positioning portions and laser beam shaping elements of other shapes and types of may also be conceived by those skilled in the art under the teaching and the enlightenment of the present disclosure. All fall within the protection scope of the present disclosure. 
     According to an exemplary embodiment of the present disclosure, the base is made of silicon (preferably, high-resistance silicon) or other materials for which a processing depth can be precisely controlled through an etching process or a chemical corrosion process. The positioning portion  5111  is formed on the silicon base through an etching process or a chemical corrosion process. Compared with ceramic materials, silicon is easier to etch and facilitates accurate control of a position and a size of the positioning portion, so that the laser beam shaping element  513  can be accurately positioned through the positioning portion  5111  to shape and modulate the laser beam emitted from the light-emitting surface of the laser emitter chip, thus reducing the angle of divergence in the fast axis. 
     According to an exemplary embodiment of the present disclosure, the laser emitter  510  further includes an electrode  514  disposed on the base. The electrode is configured to supply power to the laser emitter chip. Detailed description is given below with reference to the accompanying drawings. 
       FIG. 33A  and  FIG. 33B  show an electrode  514  according to an exemplary embodiment of the present disclosure. As shown in  FIG. 33A , the electrode  514  includes a positive electrode  5141  and a negative electrode  5142 . The positive electrode  5141  and the negative electrode  5142  are, for example, metal plates or thin metal layers (such as gold foil), and are attached to a surface of the base  511  through electroplating, for example. As shown in  FIG. 33A , the positive electrode  5141  is separated from the negative electrode  5142  by a partition  516 . The partition  516  is, for example, an integral part of the base  511  without a metal plate or a thin metal layer thereon, thereby separating the positive electrode  5141  from the negative electrode  5142  (which is shown more clearly in  FIG. 33C  and  FIG. 33D ). Alternatively, the partition  516  may also be an independent non-conductive layer, for example, a silicon dioxide layer. Both the positive electrode  5141  and the negative electrode  5142  may be disposed on the same surface of the base as the laser emitter chip and on a side surface of the base perpendicular to the light-emitting surface. For example, both the positive electrode  5141  and the negative electrode  5142  extend through two surfaces of the base  511 , that is, a top surface in  FIG. 33A  and a side surface close to an observer, to facilitate mounting. A part of the electrode soldered to the circuit board is located on the side surface of the base. In  FIG. 33A , directions (which are shown by the double-headed arrow on an upper portion of the positive electrode  5141  in  FIG. 33A ) in which upper portions (parts located on the same surface as the laser emitter chip on the base) of the positive electrode  5141  and the negative electrode  5142  extend are substantially parallel to the light-emitting surface  5121  of the laser emitter chip  512  and parallel to the direction in which the laser beam shaping element  513  extends. A lower surface of the laser emitter chip  512  is attached to the negative electrode  5142 , and has the same potential as the negative electrode  5142 . An upper surface of the laser emitter chip  512  is coupled to the positive electrode  5141  through a wire (such as a gold wire)  515 , and has the same potential as the positive electrode  5141 . The positive electrode  5141  is separated from the negative electrode  5142  by a base without an electrode material (for example, which is shown by the V groove penetrating through the upper surface of the base on a left side in  FIG. 33A ). When the laser emitter  510  is powered on, there is a voltage difference between the positive electrode  5141  and the negative electrode  5142 , thereby driving the laser emitter chip  512  to emit a laser beam from the light-emitting surface thereof. In addition, polarities of the positive electrode  5141  and the negative electrode  5142  may be transposed, which also falls within the protection scope of the present disclosure. The arrangement of the electrodes in  FIG. 35A  and  FIG. 35B  is similar to that in  FIG. 33A  and  FIG. 33B , and details are not described herein again. 
     Various components of the laser emitter  510  shown in  FIG. 33A ,  FIG. 33B ,  FIG. 35A , and  FIG. 35B  are disposed very compactly, and may be densely arranged especially when used at a transmitting end of the lidar. A limit of a spacing between the laser emitters  510  may be a thickness (that is, a size in the fast axis direction) of the laser emitter chip, which greatly increases the limit of the angular resolution of the lidar in the vertical direction. 
       FIG. 36A  and  FIG. 36B  show a laser emitter  520  according to another embodiment of the present disclosure, and  FIG. 36C  and  FIG. 36D  are renderings of  FIG. 36A  and  FIG. 36B , which show a structure of the laser emitter more clearly. The laser emitter  520  includes a base  521 , a laser emitter chip  522 , and a laser beam shaping element  523 . The base  521  has a positioning portion  5211  for assisting the accurate positioning of the laser beam shaping element  523 , which are similar to those shown in  FIG. 33A  and  FIG. 33B , and details are not described herein again. The laser emitter  520  further has an electrode  524  including a positive electrode  5241  and a negative electrode  5242 . The laser emitter chip  522  is attached to the negative electrode  5242 , and an upper surface of the laser emitter chip  522  is connected to the positive electrode  5241  through a wire (such as a gold wire)  525 . As shown in  FIG. 36A  and  FIG. 36B , the positive electrode  5241  is separated from the negative electrode  5242  by a partition. Both the positive electrode and the negative electrode are disposed on the same surface of the base as the laser emitter chip and on an end surface of the base parallel to the light-emitting surface. For example, the positive electrode  5241  and the negative electrode  5242  also extend through two surfaces of the base  521 , that is, a top surface and one of end surfaces in  FIG. 36A . As shown in  FIG. 36A  and  FIG. 36B , directions in which upper portions (parts located on the same surface as the laser emitter chip on the base) of the positive electrode  5241  and the negative electrode  5242  extend are perpendicular to the light-emitting surface  5221  of the laser emitter chip  522  and perpendicular to the direction in which the laser beam shaping element  523  extends. A part of the electrode soldered to the circuit board is located on the end surface of the base. The positive electrode  5241  is separated from the negative electrode  5242  by a base without an electrode material. In  FIG. 37A  and  FIG. 37B , the arrangement of the electrode  524  is similar to that in  FIG. 36A  and  FIG. 36B , except that a D lens and a step positioning portion are adopted. Details are not described herein again. 
     The laser emitter in the above embodiments of the present disclosure can further increase the limit of the angular resolution of a mechanical lidar in the vertical direction when applied to the lidar. The advantage will be easily understood through the following description. 
     Third Aspect 
     A third aspect of the present disclosure relates to a laser emitter emitting board assembly. The laser emitter emitting board assembly includes a circuit board and the plurality of laser emitters described above. The laser emitters are disposed on the circuit board, and light-emitting surfaces of laser emitter chips of the laser emitters are oriented in the same direction, thus emitting laser beams in the same direction. 
       FIG. 38  shows a laser emitter emitting board assembly  530  according to an exemplary embodiment of the present disclosure. The laser emitter emitting board assembly includes a circuit board  531  and a plurality of laser emitters disposed on the circuit board, such as the laser emitter  510  shown in  FIG. 33A ,  FIG. 33B ,  FIG. 35A , and  FIG. 35B , and electrodes  5141  and  5142  thereon are soldered to pads  5311  and  5312  of the circuit board  531 . As shown in  FIG. 38 , a slow axis direction of light-emitting surfaces of the plurality of laser emitters  510  is perpendicular to the circuit board  531 . During operation, the circuit board  531  provides a driving voltage for a laser emitter chip  512  in the laser emitter  510  through the pads  5311  and  5312  thereon. The laser emitter chip  512  emits a laser beam from the light-emitting surface  5121  thereof After being shaped by a laser beam shaping element, the laser beam continues to propagate at a reduced angle of divergence in the fast axis direction. 
     It is to be noted that,  FIG. 38  adaptively shows that the laser emitter  510  has an optical fiber serving as the laser beam shaping element, but it is easily understood that the laser emitter may further have laser beam shaping elements of other types such as cylindrical lenses, D lenses, or aspherical lenses. The double-headed arrow in  FIG. 38  shows the vertical direction of the lidar of  FIG. 31A . Compared with the configuration of the laser emitter chip in  FIG. 31C , in the technical solution of  FIG. 38 , the light-emitting surface of the laser emitter chip is turned by  90  degrees, and a fast axis direction (with a relatively small size) of the laser emitter chip overlaps the vertical direction of the lidar, so that more laser emitter chips can be arranged in the vertical direction of the lidar, thus improving the angular resolution of the lidar in the vertical direction. 
     In addition, as shown in  FIG. 39 , the laser emitter emitting board assembly  530  includes a plurality of circuit boards  531 , and a plurality of laser emitters  510  are disposed on each of the circuit boards. Light-emitting surfaces  5121  of laser emitter chips  512  in the laser emitters  510  on the plurality of circuit boards  531  are staggered with respect to each other in the fast axis direction. For example, in  FIG. 39 , four circuit boards  531  are disposed in a slow axis direction, and four laser emitters  510  are disposed on each of the circuit boards, which add up to  16  laser emitters  510 . Positions of the  16  laser emitters  510  are staggered with respect to each other and do not overlap in the fast axis direction in  FIG. 39  (that is, corresponding to the vertical direction of the lidar in  FIG. 38 ). In other words, when arranged in the lidar, the  16  laser emitters  510  are respectively located at different vertical heights of a focal plane of an optical exit system of the lidar, so that laser beams can be emitted at different positions for detecting surroundings. 
       FIG. 39A  includes a plurality of circuit boards in  FIG. 38  and laser emitters thereon, and is a view from a left side of  FIG. 38 . The gold wire and the laser beam shaping element are omitted for clarity. As shown in  FIG. 39 , the plurality of circuit boards  531  are stacked in the slow axis direction of the light-emitting surface. By means of such a configuration and the laser emitter module described above, the limit of the angular resolution of the lidar in the vertical direction can be greatly increased. For example, in  FIG. 39A , although the laser emitter chips of the laser emitter  510  on a single circuit board  531  need to be spaced apart by a specific distance in the vertical direction (the fast axis direction) in the figure (a stacking limit is that a bottom surface of an upper laser emitter is in contact with a top surface of a lower laser emitter) as a result of being restricted by a thickness of the base, but the laser emitters on different circuit boards  531  are not necessarily restricted by the thickness of the base and need to be staggered with respect to each other in the fast axis direction. In an extreme case, the laser emitter chips of the laser emitters on the plurality of circuit boards are consecutive in the fast axis direction. For example,  FIG. 39B  schematically shows four circuit boards  531  respectively having a laser emitter  510 - 1 , a laser emitter  510 - 2 , a laser emitter  510 - 3 , and a laser emitter  510 - 4 . A lower surface of a laser emitter chip of the laser emitter  510 - 1  and an upper surface of a laser emitter chip of the laser emitter  510 - 2  overlap, a lower surface of the laser emitter chip of the laser emitter  510 - 2  and an upper surface of a laser emitter chip of the laser emitter  510 - 3  overlap, and a lower surface of the laser emitter chip of the laser emitter  510 - 3  and an upper surface of a laser emitter chip of the laser emitter  510 - 4  overlap, which is shown by the dashed lines in  FIG. 39B . In this way, as many laser emitters as possible can be arranged in the vertical direction of the lidar. Those skilled in the art can easily understand that a plurality of laser emitters may be disposed on each of the circuit boards  531 . Therefore, compared with the arrangement in  FIG. 31  and  FIG. 32 , such an arrangement of the present disclosure can greatly increase the limit of the angle resolution of the lidar in the vertical direction. 
     The soldering method for the electrodes and the pad shown in  FIG. 39  is applicable to the semiconductor laser emitters shown in  FIG. 33A ,  FIG. 33B ,  FIG. 35A , and  FIG. 35B . Through the arrangement of the plurality of circuit PCB boards, the plurality of semiconductor laser emitters are at different heights of the focal plane of the emitting lens, thus implementing the high angular resolution in the direction of the vertical field of view. The base does not affect a final thickness, which requires the laser emitters to be staggered in the fast axis direction. 
       FIG. 40  shows a laser emitter emitting board assembly  540  according to an exemplary embodiment of the present disclosure. The laser emitter emitting board assembly includes a circuit board  541  and a plurality of laser emitters, such as the laser emitters  520  shown in  FIG. 36A ,  FIG. 36B ,  FIG. 37A , and  FIG. 37B . The laser emitters  520  are soldered on pads  5411  and  5412  of the circuit board  541  for obtaining driving voltages through the pads  5411  and  5412 , and a slow axis direction of light-emitting surfaces of laser emitter chips  522  of the plurality of laser emitters  520  is parallel to the circuit board. 
       FIG. 41  shows a laser emitter emitting board assembly  540  according to an exemplary embodiment of the present disclosure. A main difference between  FIG. 41  and  FIG. 40  is that  FIG. 41  includes a plurality of columns of laser emitters. It is easily understood that  FIG. 41  is a view from a left side of  FIG. 40 . The light-emitting surfaces of the laser emitter chips in the plurality of laser emitters on the circuit board are staggered with respect to each other in a fast axis direction. As shown in  FIG. 41 , light-emitting surfaces of laser emitter chips in the plurality of columns of laser emitters are staggered with respect to each other in the fast axis direction. Therefore, through such an arrangement mode, the arrangement density in the fast axis direction is implemented as the size of the laser emitter chip in the fast axis direction, which greatly increases the limit of the angular resolution of the lidar in the vertical direction. 
     The soldering method for the electrodes and the pad in the embodiment shown in  FIG. 41  is applicable to the semiconductor laser emitters shown in  FIG. 36A ,  FIG. 36B ,  FIG. 37A , and  FIG. 37B . Through the arrangement of the plurality of semiconductor laser emitters on the single circuit PCB board, the plurality of semiconductor laser emitters are at different heights of the focal plane of the emitting lens, thus implementing the high angular resolution in the direction of the vertical field of view. 
     Fourth Aspect 
     A fourth aspect of the present disclosure further relates to a lidar. The lidar includes the laser emitter emitting board assembly  530  or  540  described above. The third aspect of the present disclosure can further increase an optical limit of the angular resolution of the lidar in the vertical direction and improve ranging performance. 
     According to an exemplary embodiment of the present disclosure, the lidar may further include an emitting lens located downstream of the laser emitter emitting board assembly for further modulating a laser beam emitted by the laser emitter emitting board assembly, for example, changing convergence and/or a direction thereof. 
     Fifth Aspect 
       FIG. 42  shows a method  550  for encapsulating a laser emitter according to a fifth aspect of the present disclosure. The method  550  includes the following steps. 
     In step S 551 , a base is provided or prepared. The base may be usually made of a material for which a processing depth can be precisely controlled through an etching process or a chemical corrosion process, for example, silicon (preferably, high-resistance silicon). 
     In step S 552 , a positioning portion is formed on the base through etching or chemical corrosion. The positioning portion is, for example, in a form of a V-shaped groove, a U-shaped groove, a step, or a combination thereof 
     In step S 553 , a laser emitter chip is mounted on the silicon base. During the mounting, the laser emitter chip may need to be coupled to an electrode of the base, to provide a driving voltage for the laser emitter chip. 
     In step S 554 , a laser beam shaping element is positioned on the base through the positioning portion, so that a light-emitting surface of the laser emitter chip is opposite to the laser beam shaping element. For example, an accurate positioning position of the laser beam shaping element is found through the positioning portion. The positioning portion may be configured to directly fix the laser beam shaping element in place. Alternatively, in addition, after positioning, the laser beam shaping element is positioned on the positioning portion through adhesion or the like. 
     Preferably, the encapsulating method  550  further includes: causing a center of the laser beam shaping element  513  to be at the same height as a center of the light-emitting surface  5121  of the laser emitter chip  512 . 
     According to an exemplary embodiment of the present disclosure, the laser emitter chip is of an edge-emitting type, and the light-emitting surface thereof has a slow axis direction and a fast axis direction. The slow axis direction is parallel to a direction in which the laser beam shaping element extends, and the laser beam shaping element is a fast axis compression element and configured to compress an angle of divergence of a laser emitted from the light-emitting surface in the fast axis direction. 
     A limit (restricted by a fast axis size) of an angular resolution of a laser emitter emitting board assembly of the present disclosure in a vertical direction can be greatly increased. The method can be used to perform accurate fast axis compression while implementing 90° turning of the light-emitting surface of the chip. Materials such as silicon for which a processing depth and a processing size can be accurately controlled through an etching process are used to prepare a base with an accurate pattern size, which can effectively control a fast axis compressed angle of divergence and beam directivity, thus improving ranging performance. In addition, the light-emitting surface of the chip is turned by 90°, which facilitates more reduction of measurement errors in ground lane lines, pedestrian lines, and distant ground. 
     Those skilled in the art can easily understand that the lidar in the first aspect described above may be randomly combined with the technical solutions disclosed in the second aspect, the third aspect, the fourth aspect, and the fifth aspect described above. 
     For example, as shown in  FIG. 14 , in the lidar according to the embodiment of the first aspect of the present disclosure, at least one laser emitter  2015  is disposed on the laser emitter emitting board  2014 . The laser emitter  2015  may be, for example, the laser emitter  510  and/or the laser emitter  520  shown in  FIG. 33A  to  FIG. 33D ,  FIG. 35A ,  FIG. 35B ,  FIG. 36A  to  FIG. 36D ,  FIG. 37A , and  FIG. 37D . 
     In addition, the laser emitter emitting board  2014  includes, for example, the laser emitter emitting board assembly  530  (which is shown in  FIG. 38 ) involved in the third aspect of the present disclosure. The laser emitter emitting board assembly  530  includes a circuit board  531  and a plurality of laser emitters  510  disposed on the circuit board. With reference to  FIG. 14 ,  FIG. 38 , and  FIG. 39 , a laser emitter bracket  2011  has a comb structure with a plurality of vertical slots. Laser emitter emitting boards (corresponding to the laser emitter emitting board assembly  530  or including the laser emitter emitting board assembly  530 ) are respectively disposed in a plurality of slots  201122 . Light-emitting surfaces of laser emitter chips of the laser emitter emitting boards in the plurality of slots are staggered with respect to each other in a fast axis direction. A plurality of laser emitter emitting boards  2014  are disposed in the slots  201122  of the comb structure, and the laser emitter emitting board assembly  530  shown in  FIG. 38  is disposed on each of the laser emitter emitting boards  2014 . Each laser emitter emitting board assembly  530  includes a plurality of laser emitters  510  arranged in a vertical direction, and light-emitting surfaces  5121  of laser emitter chips  512  on the laser emitters  510  on a plurality of circuit boards  531  are staggered with respect to each other in the fast axis direction, to form a light-emitting structure shown in  FIG. 39 . As shown in  FIG. 39 , the plurality of circuit boards  531  are stacked in a slow axis direction of the light-emitting surface. By means of such a configuration and the laser emitter described above, the limit of the angular resolution of the lidar in the vertical direction can be greatly increased. For example, in  FIG. 39 , although the laser emitter chips of the laser emitter  510  on a single circuit board  531  need to be spaced apart by a specific distance in the vertical direction (the fast axis direction) in the figure (a stacking limit is that a bottom surface of an upper laser emitter is in contact with a top surface of a lower laser emitter) as a result of being restricted by a thickness of the base, but the laser emitters on different circuit boards  531  are not necessarily restricted by the thickness of the base and need to be staggered with respect to each other in the fast axis direction. In an extreme case, the laser emitter chips of the laser emitters on the plurality of circuit boards are consecutive in the fast axis direction. Therefore, compared with the arrangement in  FIG. 31  and  FIG. 32 , such an arrangement of the present disclosure can greatly increase the limit of the angle resolution of the lidar in the vertical direction. 
     In addition, those skilled in the art may also conceive a combination of a laser emitter emitting board assembly  540  shown in  FIG. 40  and  FIG. 41  into the embodiments shown in  FIG. 1  to  FIG. 30 . For example, a laser emitter bracket  2011  may not be provided with the comb structure shown in  FIG. 14 , but includes a bracket structure for supporting or fixing the laser emitter emitting board assembly  540  shown in  FIG. 40  and  FIG. 41 . Through the laser emitter emitting board assembly shown in  FIG. 40  and  FIG. 41 , the limit of the angular resolution of the lidar in the vertical direction can be effectively increased. Details are not described herein again. 
     The foregoing descriptions are merely example embodiments of the present disclosure, but are not intended to limit the present disclosure. Any modification, equivalent replacement, and improvement made without departing from the spirit and principle of the present disclosure shall fall within the protection scope of the present disclosure.