A lidar, comprising: a rotor , wherein the rotor has an emitting chamber and a receiving chamber that are separated from each other, wherein the emitting chamber and the receiving chamber are asymmetrically distributed; a laser emitting system disposed in the emitting chamber and comprising 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 , wherein the laser emitting system comprises a laser emitter disposed on the laser emitter emitting board , wherein the laser emitter comprises: a base having a positioning portion thereon; a laser emitter chip disposed on the base and having a light-emitting surface ; and a laser beam shaping element positioned opposite to the light-emitting surface of the laser emitter chip through the positioning portion , wherein the laser emitter emitting board comprises a circuit board and a plurality of laser emitters disposed on the circuit board , wherein light-emitting surfaces of laser emitter chips of the laser emitters are oriented in the same direction, wherein the plurality of laser emitters are soldered on the circuit board , wherein a slow axis direction of the light-emitting surfaces of the plurality of laser emitters are perpendicular to the circuit board . a rotor , wherein the rotor has an emitting chamber and a receiving chamber that are separated from each other, wherein the emitting chamber and the receiving chamber are asymmetrically distributed; a laser emitting system disposed in the emitting chamber and comprising 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 , wherein the laser emitting system comprises a laser emitter disposed on the laser emitter emitting board , wherein the laser emitter comprises: a base having a positioning portion thereon; a laser emitter chip disposed on the base and having a light-emitting surface ; and a laser beam shaping element positioned opposite to the light-emitting surface of the laser emitter chip through the positioning portion , wherein the laser emitter emitting board comprises a circuit board and a plurality of laser emitters disposed on the circuit board , wherein light-emitting surfaces of laser emitter chips of the laser emitters are oriented in the same direction, wherein the plurality of laser emitters are soldered on the circuit board , wherein a slow axis direction of the light-emitting surfaces of the plurality of laser emitters are perpendicular to the circuit board . a base having a positioning portion thereon; a laser emitter chip disposed on the base and having a light-emitting surface ; and a laser beam shaping element positioned opposite to the light-emitting surface of the laser emitter chip through the positioning portion , wherein the laser emitter emitting board comprises a circuit board and a plurality of laser emitters disposed on the circuit board , wherein light-emitting surfaces of laser emitter chips of the laser emitters are oriented in the same direction, wherein the plurality of laser emitters are soldered on the circuit board , wherein a slow axis direction of the light-emitting surfaces of the plurality of laser emitters are perpendicular to the circuit board . <EOS>