Laser radar and mobile device

Abstract

The embodiment of the invention discloses a laser radar and a mobile device, the laser radar comprises a light source module, a light path separation module, a first microlens array, a second microlens array, a lens and a silicon optical chip, and the light source module is used for generating multiple beams of detection light; the light path separation module is used for receiving the detection light, emitting the detection light, receiving echo light and emitting the echo light, and the first microlens array is arranged on the upstream of the first end face in the transmission direction of the detection light; the second microlens array is arranged at the downstream of the second end face along the transmission direction of the detection light; the lens is arranged at the downstream of the second micro-lens array along the transmission direction of the detection light; the silicon optical chip is arranged at the downstream of the third end face along the transmission direction of the echo light, and an optical fiber coupling silicon optical chip is not needed, so that the energy loss of the detection light is reduced, the requirement of the maximum output energy of the light source module can be reduced, and the overall size of the laser radar can be reduced.

Description

Technical Field

[0001] The present application relates to the field of laser radar technology, and in particular to a laser radar and a movable device. Background Art

[0002] In the relevant technical field, Frequency Modulated Continuous Wave (FMCW) lidar technology usually transmits detection light through a transmitting waveguide integrated in a silicon photonic chip, and receives echo light through a receiving waveguide integrated in the silicon photonic chip. However, this method requires coupling the optical fiber with the silicon photonic chip to realize the transmission of the detection light signal to the transmitting waveguide in the silicon photonic chip, and the transmission of the echo light signal to the receiving waveguide in the silicon photonic chip. Since the optical fiber coupling silicon photonic chip will produce about 30% energy loss, the loss of the entire transceiver link is relatively large. Summary of the invention

[0003] The embodiments of the present application provide a laser radar and a movable device, which are intended to reduce the energy loss of detection light. Compared with the technical solution of using optical fiber to couple with silicon photonic chips, the present application does not need to use optical fiber to couple with silicon photonic chips, thereby reducing the energy loss of coupling and lowering the requirement for the maximum output energy of the light source module.

[0004] The embodiment of the present application provides a laser radar, including a light source module, an optical path separation module, a first microlens array, a second microlens array, a lens and a silicon photonic chip, wherein the light source module is used to generate multiple beams of detection light, and each detection light is transmitted in parallel; the optical path separation module has a first end face, a second end face and a third end face, the first end face is used to receive each detection light, and the direction in which the detection light is emitted toward the first end face is a first direction, the second end face is used to emit the detection light and receive the echo light, the detection light emitted through the second end face is arranged at intervals along the second direction, the second direction is parallel to the second end face, and the third end face is used to emit the echo light, wherein the echo light is formed after the detection light is reflected by the target object; the first microlens array is arranged upstream of the first end face along the transmission direction of the detection light, the first microlens includes a plurality of first microlenses, each first microlens corresponds to a detection light, and the first microlens is used to detect the detection light. The light is collimated; a second microlens array is arranged downstream of the second end face along the transmission direction of the detection light, the second microlens array includes a plurality of second microlenses, each second microlens corresponds to a first microlens, and the second microlens is used to focus the detection light; a lens is arranged downstream of the second microlens array along the transmission direction of the detection light, so as to receive the detection light emitted by each second microlens and collimate it, the lens has a first focal plane located on a side close to the second microlens array, the second microlens has a second focal plane located on a side close to the lens, and the first focal plane is coplanar with the second focal plane of each second microlens; a silicon photonic chip is arranged downstream of the third end face along the transmission direction of the echo light, the silicon photonic chip includes a plurality of light receiving elements, each light receiving element corresponds to a second microlens, the light receiving element is used to receive the echo light emitted through the optical path separation module, and each light receiving element is arranged at intervals along the second direction.

[0005] In some of the embodiments, the light source module includes a light source and multiple optical amplifiers. The light source is used to generate multiple detection light beams, and the detection lights are arranged in parallel. Each optical amplifier corresponds to one detection light, and the optical amplifier is used to amplify the detection light generated by the laser.

[0006] In some embodiments, the light source includes multiple lasers, the lasers are used to generate detection light, and each optical amplifier is set corresponding to a laser; or, the light source includes a laser and a splitter, the laser is used to generate a source light signal, and the splitter is used to receive the source light signal and split it into multiple beams of detection light.

[0007] In some embodiments, the second direction is parallel to the first end face, and each optical amplifier is arranged at intervals along the third direction; the laser radar also includes a first reflection module, which is arranged between each optical amplifier and the optical path separation module along the transmission optical path of the detection light, and the first reflection module has a plurality of mutually parallel first reflection surfaces, each first reflection surface corresponds to an optical amplifier, and the first reflection surface is used to reflect the detection light output by the optical amplifier so that the detection light is emitted to the first end face along the first direction, and any two first reflection surfaces are staggered along the first direction and the second direction; the centers of two adjacent optical amplifiers along the third direction are relatively offset by a first distance along the third direction, and the centers of two adjacent first reflection surfaces along the second direction are relatively offset by a second distance along the second direction, and the second distance is less than the first distance. Wherein, when observed along a direction perpendicular to the first direction and the second direction, the third direction and the second direction have an angle.

[0008] In some embodiments, the first end surface and the second end surface are two adjacent end surfaces of the optical path separation module.

[0009] In some embodiments, the first end surface and the second end surface are two opposite end surfaces of the optical path separation module.

[0010] In some of the embodiments, the laser radar also includes a second reflection module; the second reflection module is arranged on a side of the optical path separation module having a second end face, the second reflection module has a second reflection surface, the second reflection surface and the second end face are arranged relative to each other along a fourth direction, the fourth direction is perpendicular to the second end face, the second reflection surface is used to reflect the detection light emitted through the second end face, and along the second direction, the distance between the second reflection surface and the second end face gradually increases or decreases, so that each detection light reflected by the second reflection surface is arranged at intervals along the fourth direction; wherein, each second microlens is arranged relative to the second reflection surface along the second direction, and each second microlens is arranged along the fourth direction.

[0011] In some of the embodiments, the laser radar also includes a third microlens array; the third microlens array is arranged between the optical path separation module and the silicon photonic chip, the third microlens array includes a plurality of third microlenses, each third microlens corresponds to a light receiving element, and the third microlens is used to focus the echo light emitted from the optical path separation module.

[0012] In some embodiments, the light receiving element is a grating, and the length direction of the grating is perpendicular to the second direction.

[0013] In some of the embodiments, the laser radar further includes a quarter wave plate; the quarter wave plate is disposed between the second end lenses and is used to change the linearly polarized detection light into circularly polarized detection light.

[0014] In some embodiments, the optical path separation module is a polarization beam splitter prism.

[0015] In some embodiments, the diameters of the first microlens and the second microlens are both less than or equal to 1 mm; the diameter of the lens is less than or equal to 30 mm; the ratio of the diameter of the lens to the diameter of the first microlens is greater than or equal to 10; the ratio of the diameter of the lens to the diameter of the second microlens is greater than or equal to 10.

[0016] An embodiment of the present application also provides a movable device, including a movable main body and a laser radar, wherein the laser radar is arranged on the main body.

[0017] Based on the laser radar of the present application, the detection light generated by the light source module is collimated by the first microlens array to reduce the divergence angle of the detection light, and then the detection light emitted by the optical path separation module is focused by the second microlens array, so that the divergence angle of the detection light emitted through the lens can be reduced to reduce the spot of the detection light, thereby reducing the energy loss of the detection light; and because the energy loss of the detection light is small, the energy intensity of the echo light formed by the reflection of the target object can be increased to increase the energy intensity of the echo light received by the light receiving element, thereby improving the detection accuracy of the laser radar. Furthermore, compared with the technical solution of coupling optical fiber with silicon photonic chip, the present application does not need to use optical fiber to couple silicon photonic chip, thereby reducing the energy loss of coupling and reducing the maximum output energy requirement of the light source module. And because the echo light can first be focused by the lens to reduce the spot of the echo light, and then collimated by the second microlens array, and then incident on the light receiving element through the optical path separation module, the volume of the silicon photonic chip can be reduced to reduce the overall volume of the laser radar. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without paying any creative work.

[0019] Figure 1 This is a schematic diagram of a laser radar in one embodiment of the present application;

[0020] Figure 2 This is a schematic diagram of the side view structure of a laser radar in one embodiment of the present application;

[0021] Figure 3 This is a schematic diagram of the three-dimensional structure of a laser radar in another embodiment of the present application;

[0022] Figure 4 for Figure 3 A schematic diagram of the enlarged structure at A in the middle;

[0023] Figure 5 This is a schematic diagram of the three-dimensional structure of a laser radar in another embodiment of the present application;

[0024] Figure 6 for Figure 5 A schematic diagram of the enlarged structure at B in the middle;

[0025] Figure 7 It is a schematic diagram of a movable device in an embodiment of the present application.

[0026] Explanation of the accompanying drawings: 1. laser radar; 11. light source module; 111. light source; 12. optical path separation module; 12A. first end face; 12B. second end face; 12C. third end face; 121. right-angle prism; 122. polarization beam splitting film; 13. first microlens array; 131. first microlens; 14. second microlens array; 141. second microlens; 15. lens; 16. silicon photonic chip; 161. chip body; 162. light receiving element; 17. scanning module; 18. first reflection module; 18A. first reflection surface; 19. second reflection module; 19A. second reflection surface; 20. third microlens array; 21. quarter wave plate; 22. packaging box; 22A. light outlet; 22B. side wall; a. detection light; b. echo light; W, first direction; X, second direction; Y, third direction; Z, fourth direction; 2. movable device; 21. main body. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0028] Please refer to Figure 1 and Figure 2 An embodiment of the present application provides a laser radar 1, including a light source module 11, an optical path separation module 12, a first microlens array 13, a second microlens array 14, a lens 15, a silicon photonic chip 16 and a scanning module 17.

[0029] For the above light source module 11, please refer to Figure 1 to Figure 2 , the light source module 11 is used to generate multiple beams of detection light a, and each detection light a is transmitted in parallel. In a specific embodiment, the light source module 11 includes a light source 111 and a plurality of optical amplifiers, the light source 111 is used to generate multiple beams of detection light a, and each detection light a is arranged in parallel; each optical amplifier corresponds to a detection light a, and the optical amplifier is used to amplify the detection light a generated by the laser to reduce the loss of the detection light a during the transmission process, thereby improving the detection accuracy of the laser radar 1.

[0030] Please refer to Figure 1 and Figure 2 In a specific embodiment, the light source 111 may include multiple lasers, which are used to generate detection light a. Each optical amplifier corresponds to a laser setting, and multiple lasers are used to generate multiple detection lights a, so that the number of lasers turned on can be changed according to actual usage requirements, thereby changing the detection field of view of the laser radar 1.

[0031] It is understandable that the light source 111 may also include a laser and a spectrometer, the laser is used to generate a source light signal, the spectrometer is used to receive the source light signal and split it into multiple beams of detection light a. Compared with using multiple lasers, the use of lasers and spectrometers can reduce the volume of the light source module 11, and since the number of lasers is reduced, the cost of the light source module 11 can be reduced, thereby reducing the cost of the laser radar 1. And compared with using multiple lasers, the use of lasers and spectrometers can reduce the heat generation of the light source module 11, thereby reducing other components used to dissipate heat from the light source 111, and further reducing the volume and cost of the laser radar 1.

[0032] For the above optical path separation module 12, please refer to Figure 2 The optical path separation module 12 has a first end face 12A, a second end face 12B and a third end face 12C. The first end face 12A is used to receive each detection light a, wherein the direction in which the detection light a is emitted to the first end face 12A is the first direction W. The second end face 12B is used to emit the detection light a and receive the echo light b, and the detection light a emitted through the second end face 12B is arranged at intervals along the second direction X, and the second direction X is parallel to the second end face 12B. The third end face 12C is used to emit the echo light b, wherein the echo light b is formed after the detection light a is reflected by the target object. In an embodiment of the present application, the optical path separation module 12 is a polarization splitter prism, which is used to separate the emission optical path and the receiving optical path by polarization splitting, wherein the emission optical path passes by reflection or transmission, and the echo optical path passes by transmission or reflection, so that the light source module 11 and the silicon photonic chip 16 can be separately set, avoiding the use of the solution of optical fiber coupling between the light source 111 and the silicon photonic chip 16 on the detection optical path, thereby improving the emission efficiency of the detection light a.

[0033] Please refer to Figure 1 and Figure 2 In a specific embodiment, the optical path separation module 12 is a polarization beam splitter prism, which includes two right-angle prisms 121 and a polarization beam splitter film 122 , and the inclined surfaces of the two right-angle prisms 121 are respectively connected to two opposite surfaces of the polarization beam splitter film 122 .

[0034] Please refer to Figure 1 and Figure 2Exemplarily, the first end face 12A and the second end face 12B can be the two adjacent end faces of the optical path separation module 12, and accordingly, the detection light a should be configured to be reflected by the polarization beam splitting mode 122, that is, s light; at this time, the polarization beam splitting film 122 is used to receive the detection light a emitted by the first microlens 131 and reflect it, so that the reflected detection light a is emitted to the second microlens array 14, and the polarization beam splitting film 122 is used to transmit the echo light b emitted by the second microlens 141, so that the echo light b transmitted by the polarization beam splitting film 122 is emitted into the silicon photonic chip 16.

[0035] It can be understood that the first end face 12A and the second end face 12B can be the two opposite end faces of the optical path separation module 12, and accordingly, the detection light a should be configured to be transmitted through the polarization beam splitting mode 122, that is, p light; at this time, the polarization beam splitting film 122 can be used to receive the detection light a emitted by the first microlens 131 and transmit it, so that the transmitted detection light a is emitted to the second microlens array 14; and the polarization beam splitting film 122 is used to reflect the echo light b emitted by the second microlens 141, so that the echo light b reflected by the polarization beam splitting film 122 is emitted into the silicon photonic chip 16.

[0036] It is worth mentioning that the present application does not limit the specific structure of the optical path separation module 12, as long as it has the above-mentioned first to third end faces and can realize the separation of the detection light path and the echo light path; for example, in some other embodiments, the optical path separation module 12 can also be an optical circulator, a reflector with a slit, or other elements that can realize the separation of the detection light path and the echo light path.

[0037] For the first microlens array 13, please continue to refer to Figure 2 The first microlens array 13 is arranged upstream of the first end face 12A along the transmission direction of the detection light a. The first microlens 131 includes a plurality of first microlenses 131. Each first microlens 131 corresponds to a detection light a. The first microlens 131 is used to collimate the detection light a. In this embodiment, the first microlens 131 means a lens with a diameter less than or equal to 1 mm. The first microlens array 13 is arranged to collimate the detection light a while reducing the space occupied in the laser radar 1 to reduce the volume of the laser radar 1.

[0038] For the second microlens array 14, please continue to refer to Figure 2The second microlens array 14 is arranged downstream of the second end face 12B along the transmission direction of the detection light a. The second microlens array 14 includes a plurality of second microlenses 141. Each second microlens 141 corresponds to a first microlens 131. The second microlens 141 is used to focus the detection light a. In this embodiment, the second microlens 141 means a lens with a diameter less than or equal to 1 mm. The second microlens array 14 is arranged to focus the detection light a while reducing the space occupied in the laser radar 1, so as to reduce the volume of the laser radar 1.

[0039] For the above lens 15, please continue to refer to Figure 2 The lens 15 is arranged downstream of the second microlens array 14 along the transmission direction of the detection light a, so as to receive and collimate the detection light a emitted by each second microlens 141, and the lens 15 has a first focal plane located on the side close to the second microlens array 14, and the second microlens 141 has a second focal plane located on the side close to the lens 15, and the first focal plane is coplanar with the second focal plane of each second microlens 141. Exemplarily, the diameter of the lens 15 is less than or equal to 30 mm, so that the lens 15 is small, so that the space occupied by the lens 15 in the laser radar 1 can be reduced, so as to reduce the volume of the laser radar 1.

[0040] Please refer to Figure 1 and Figure 2 In a specific embodiment, the ratio of the diameter of the lens 15 to the diameter of the first microlens 131 is greater than or equal to 10; the ratio of the diameter of the lens 15 to the diameter of the second microlens 141 is greater than or equal to 10. On the one hand, since the detection light a is focused on the second focal plane after passing through the second microlens 141 and then diverges, the lens 15 with a larger aperture is more conducive to receiving the diverged detection light a and collimating it; on the other hand, the lens 15 with a larger aperture can also receive more echo light b, thereby increasing the optical power of the echo light b coupled to the silicon photonic chip 16, thereby improving the detection performance of the laser radar 1.

[0041] The silicon photonic chip 16 is arranged downstream of the third end face 12C along the transmission direction of the echo light b. Exemplarily, the silicon photonic chip 16 includes a chip body 161 and a plurality of light receiving elements 162 arranged on the chip body 161, and the light receiving elements 162 are used to receive the echo light b emitted through the optical path separation module 12; each light receiving element 162 is arranged at intervals along the second direction X to correspondingly receive the echo light b corresponding to each detection light a. The chip body 161 is the base of the silicon photonic chip 16, and may include a substrate and a cladding. Among them, the substrate is a base material for laying the cladding. Exemplarily, the substrate is made of silicon, and it can be understood that in other embodiments, the substrate can also be made of other suitable materials, such as silicon dioxide, silicon oxynitride, etc. The cladding is laid on the substrate, and the cladding is the main structure of the silicon photonic chip 16; the cladding can be made of materials such as silicon dioxide and / or silicon nitride.

[0042] The scanning module 17 is located downstream of the optical path of the lens 15 along the optical path of the detection light a. The scanning module 17 is used to receive the detection light a emitted by the lens 15 and perform two-dimensional deflection so that the detection light a forms a specific detection field of view outside the laser radar 1. The scanning module 17 may include a galvanometer and / or a rotating mirror, etc., which is not limited in the embodiments of the present application.

[0043] The optical path of this embodiment is as follows: the detection light a generated by the light source module 11 is sequentially irradiated on the target object through the first microlens 131, the first end face 12A of the optical path separation module 12, the second end face 12B of the optical path separation module 12, the second microlens 141, the lens 15, and the scanning module 17. The target object reflects the detection light a to form an echo light b, which is sequentially incident on the light receiving element 162 through the scanning module 17, the lens 15, the second microlens 141, the second end face 12B of the optical path separation module 12, and the third end face 12C of the optical path separation module 12, thereby completing the detection of the target object.

[0044] It is understandable that the positions of the light source module 11 and the light receiving element 162 are interchangeable, and the purpose of detecting the target object can also be achieved, which will not be described in detail here.

[0045] In the embodiment of the present application, the first microlens array 13 is used to collimate the detection light a generated by the light source module 11, so as to reduce the divergence angle of the detection light a on the one hand, and make each detection light a approximately parallel light on the other hand, so that each second microlens 141 can focus the detection light a at a position at the same distance from the second end face 12B, and make the focal points of each detection light a coplanar, and then further collimate each detection light a through the same lens 15, and the second microlens 141 cooperates with the lens 15 to expand the detection light a, thereby reducing the divergence angle of the detection light a emitted through the lens 15, thereby reducing the size of the spot formed when the detection light a falls on the target object, which is beneficial to improve the energy intensity of the echo light b received by the light receiving element 162 and improve the detection accuracy of the laser radar 1. Furthermore, compared with the technical solution of coupling the optical fiber with the silicon photonic chip 16, the present application does not need to use the optical fiber to couple the silicon photonic chip 16, so as to emit the detection light a through the silicon photonic chip 16, thereby reducing the energy loss of the coupling, reducing the requirement of the maximum output energy of the light source module 11, thereby reducing the cost of the light source module 11, and thus reducing the cost of the laser radar 1. And because the echo light b can first be focused by the lens 15, and then collimated by the second microlens array 14, the echo light b can be narrowed to reduce the spot area, and then incident on the light receiving element 162 through the optical path separation module 12, thereby reducing the spot size of the echo light b irradiated on the light receiving element 162, so as to reduce the size of the light receiving element 162, and then reduce the volume of the silicon photonic chip 16, so as to reduce the overall volume of the laser radar 1.

[0046] Please refer to Figure 1-4In a specific embodiment, the second direction X is parallel to the first end face 12A, and each optical amplifier is arranged at intervals along the third direction Y; the laser radar 1 also includes a first reflection module 18, which is arranged along the transmission optical path of the detection light a, and between each optical amplifier and the optical path separation module 12. The first reflection module 18 has a plurality of mutually parallel first reflection surfaces 18A, each of which corresponds to an optical amplifier, and the first reflection surface 18A is used to reflect the detection light a output by the optical amplifier, so that the detection light a is emitted toward the first end face 12A along the first direction W, and any two first reflection surfaces 18A are staggered along the first direction W and the second direction X. When observed in a direction perpendicular to the first direction W and the second direction X, the centers of the two adjacent optical amplifiers along the third direction Y are relatively offset by a first distance along the third direction Y, and the centers of the two adjacent first reflection surfaces 18A along the second direction X are relatively offset by a second distance along the second direction X, and the second distance is smaller than the first distance, so that the first reflection module 18 can be used to compress the distance between the two adjacent detection lights a incident on the first end surface 12A, so as to overcome the disadvantage that the distance between the two optical amplifiers is large and the spacing between the adjacent detection lights a is also large, which is beneficial to reduce the volume of the optical path separation module 12, the lens 15 and the silicon photonic chip 16, and further reduce the volume of the laser radar 1, and is also beneficial to avoid the risk that each detection light a fails to fall on the scanning module 17. It should be noted that when observed in a direction perpendicular to the first direction and the second direction, the third direction has an angle with the second direction; for example, in this embodiment, the third direction Y is parallel to the first direction W, and of course, the third direction Y has an angle with the first direction W that is not 90 degrees.

[0047] Specifically, the first reflection surface 18A can be a coating or a plane mirror. The detection light a can be first emitted into the first reflection module 18 and then reflected by the first reflection surface 18A, or it can be outside the first reflection module 18 and reflected by the first reflection surface 18A; in addition, the first reflection surface 18A can reflect the detection light a by mirror reflection, or it can reflect the detection light a by total reflection. In the embodiment of the present application, there is no restriction on the specific form of the first reflection surface 18A and the specific form of the first reflection module 18, as long as they can realize the reflection of the detection light a.

[0048] Please refer to Figure 3 and Figure 4 Specifically, the laser radar 1 also includes a packaging box 22, and the light source module 11, the optical path separation module 12, the first microlens array 13, the second microlens array 14 and the silicon photonic chip 16 are all arranged in the packaging box 22 to improve the integration of the above components. The packaging box 22 has a light outlet 22A and a side wall 22B. The packaging box 22 and the components contained therein are arranged as a whole, together with the above-mentioned lens 15 and the scanning module 17, in the housing of the laser radar 1.

[0049] In this embodiment, the second direction X corresponds to the vertical direction, and the detection fields of the detection lights a outside the laser radar 1 are stacked in the vertical direction to form the total detection field of the laser radar 1. Based on this, the gratings also need to be arranged at intervals in the vertical direction, so the silicon photonic chip 16 as a whole needs to be as follows: Figure 4 The light source module 11 , the light path separation module 12 , the first microlens array 13 , the second microlens array 14 , the silicon photonic chip 16 and the first reflection module 18 are all suspended relative to the bottom wall of the packaging box 22 .

[0050] Please refer to Figure 1 , Figure 2 , Figure 5 and Figure 6 In a specific embodiment, the laser radar 1 also includes a second reflection module 19; the second reflection module 19 is arranged on a side of the optical path separation module 12 having the second end face 12B, the second reflection module 19 has a second reflection surface 19A, the second reflection surface 19A and the second end face 12B are arranged relative to each other along a fourth direction Z, the fourth direction Z is perpendicular to the second end face 12B, the second reflection surface 19A is used to reflect the detection light a emitted through the second end face 12B, along the second direction X, the distance between the second reflection surface 19A and the second end face 12B gradually increases or gradually decreases, so that each detection light a reflected by the second reflection surface 19A is arranged at intervals along the fourth direction Z; wherein, each second microlens 141 is arranged relative to the second reflection surface 19A along the second direction X, and each second microlens 141 is arranged along the fourth direction Z.

[0051] In this embodiment, the fourth direction Z corresponds to the vertical direction, and the detection fields of the detection lights a outside the laser radar 1 are stacked in the vertical direction to form the total detection field of the laser radar 1. Based on this, the gratings can also be arranged at intervals in the horizontal direction, and the silicon photonic chip 16 as a whole can be as follows: Figure 6 Accordingly, the distances between the light source module 11, the optical path separation module 12 and the first reflection module 18 and the bottom of the packaging box 22 are relatively small, and some of the components can even directly fit the bottom wall 22C of the packaging box 22, so the structural reliability will be higher and the assembly and adjustment of the above components will be simpler.

[0052] Please refer to Figure 1-6In a specific embodiment, the laser radar 1 further includes a third microlens array 20. The third microlens array 20 is disposed between the optical path separation module 12 and the silicon photonic chip 16. The third microlens array 15 is located on the side of the optical path separation module 12 having the third end face 12C, and includes a plurality of third microlenses 201. Each third microlens 201 corresponds to a light receiving element 162. The third microlens 201 is used to focus the echo light b emitted from the optical path separation module 12, thereby improving the coupling efficiency of the light receiving element 162 when receiving light.

[0053] Please refer to Figure 1 and Figure 2 In a specific embodiment, the light receiving element 162 can be a grating. Since the scanning module 17 is a movable element, when the echo light b returns to the scanning module 17, the scanning module 17 has deflected an angle compared to the emitted detection light a, so that the position where the echo light b falls on the grating is a dot matrix along a specific direction of the grating, wherein, as the scanning module 17 moves, the light spot of the echo light b moves, and the moving distance is related to the flight time / distance of the light signal during the detection process. The above effect is called the walk-off effect of the laser radar 1. Generally speaking, the fast axis scanning rate of the laser radar 1 is significantly larger than the slow axis scanning rate, and the walk-off effect caused by it is also more obvious, so it is necessary to improve this deficiency. Each detection light a is staggered in the second direction X shown in the figure, and the field of view formed by each detection light a is stacked in the second direction X to form the total detection field of view of the laser radar 1; in some embodiments, the second direction X corresponds to the slow axis scanning direction of the laser radar 1; then, the fast axis scanning direction of the laser radar 1 is a direction perpendicular to the second direction X, and the direction of the walk-off effect caused by it is also perpendicular to the second direction X. In order to ensure that the grating can receive the echo light b, the length direction of the grating is configured to be perpendicular to the second direction X, that is, the length direction of the grating is consistent with the walk-off direction of the echo light b, so that the light spot of the echo light b can still be received by the grating when it is offset due to the walk-off effect.

[0054] Please refer to Figure 1 and Figure 2In a specific embodiment, the laser radar 1 may further include a quarter wave plate 21. The quarter wave plate 21 is disposed between the second end face 12B lens 15, and the linearly polarized detection light a is changed into the circularly polarized detection light a by using the quarter wave plate, and the circularly polarized echo light b can be changed into the linearly polarized echo light b. The polarization directions of the detection light that has not passed through the quarter wave plate 21 and the echo light that has passed through the quarter wave plate 21 differ by 90 degrees, so the detection light path and the echo light path can be separated by a polarization splitter prism. Since the polarization direction of the echo light b reflected by the target object is mostly still the same as the polarization direction of the detection light a before reflection, compared with not setting the quarter wave plate 21, this embodiment can receive more echo light signals to a certain extent, that is, it can improve the receiving efficiency of the echo signal.

[0055] Please refer to Figure 7 The embodiment of the present application also provides a movable device 2, including a movable main body 21, and a laser radar 1 mounted on the main body 21. The movable device 2 of this embodiment can be one of a car, a robot, and a drone. Correspondingly, the main body 21 is the body of a car, the body of a robot, and the body of a drone. Of course, the specific structure of the movable device is not limited to this. Among them, taking the movable device 2 as an electric car as an example, the electric car scans the surrounding environment through the laser radar 1 to obtain information such as the terrain of the surrounding environment, the position and speed of active objects, etc., for the automatic driving of the vehicle.

[0056] The same or similar numbers in the drawings of this embodiment correspond to the same or similar parts; in the description of this application, it should be understood that if the terms "up", "down", "left", "right", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the drawings, it is only for the convenience of describing this application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, the terms describing the positional relationship in the drawings are only used for illustrative purposes and cannot be understood as limitations on this application. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0057] The above are only preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A laser radar, characterized in that: include: A light source module, used for generating multiple beams of detection light, wherein the detection lights are transmitted in parallel; An optical path separation module, comprising a first end face, a second end face and a third end face, wherein the first end face is used to receive each of the detection lights, the direction in which the detection lights are emitted toward the first end face is a first direction, the second end face is used to emit detection lights and receive echo lights, the detection lights emitted through the second end face are arranged at intervals along a second direction, the second direction is parallel to the second end face, and the third end face is used to emit echo lights, wherein the echo lights are formed after the detection lights are reflected by a target object; A first microlens array is arranged upstream of the first end face along the transmission direction of the detection light, the first microlens includes a plurality of first microlenses, each of the first microlenses corresponds to one detection light, and the first microlens is used to collimate the detection light; a second microlens array, disposed downstream of the second end face along the transmission direction of the detection light, the second microlens array comprising a plurality of second microlenses, each of the second microlenses corresponding to one of the first microlenses, and the second microlenses being used to focus the detection light; a lens, arranged downstream of the second microlens array along the transmission direction of the detection light, for receiving and collimating the detection light emitted by each of the second microlenses, the lens having a first focal plane located on a side close to the second microlens array, the second microlens having a second focal plane located on a side close to the lens, and the first focal plane being coplanar with the second focal plane of each of the second microlenses; and A silicon photonic chip is arranged downstream of the third end face along the transmission direction of the echo light. The silicon photonic chip includes a plurality of light receiving elements, each of which corresponds to a second microlens. The light receiving element is used to receive the echo light emitted through the optical path separation module. The light receiving elements are arranged at intervals along the second direction.

2. The laser radar according to claim 1, characterized in that The light source module comprises: A light source, used to generate a plurality of detection lights, each of which is arranged in parallel; and A plurality of optical amplifiers, each of which corresponds to one detection light, and is used to amplify the detection light generated by the laser.

3. The laser radar according to claim 2, characterized in that The light source comprises: A plurality of lasers, wherein the lasers are used to generate detection light, and each of the optical amplifiers is provided corresponding to one of the lasers; or, A laser and a beam splitter, wherein the laser is used to generate a source light signal, and the beam splitter is used to receive the source light signal and split it into a plurality of beams of detection light.

4. The laser radar according to claim 2, characterized in that The second direction is parallel to the first end face, and the optical amplifiers are arranged at intervals along the third direction; The laser radar further includes a first reflection module, which is arranged between each of the optical amplifiers and the optical path separation module along the transmission optical path of the detection light, and has a plurality of mutually parallel first reflection surfaces, each of which corresponds to an optical amplifier, and is used to reflect the detection light output by the optical amplifier so that the detection light is emitted toward the first end face along the first direction, and any two of the first reflection surfaces are staggered along the first direction and the second direction; The centers of two adjacent optical amplifiers along the third direction are relatively offset by a first distance along the third direction, and the centers of two adjacent first reflection surfaces along the second direction are relatively offset by a second distance along the second direction, and the second distance is smaller than the first distance; Wherein, when viewed along a direction perpendicular to the first direction and the second direction, the third direction has an angle with the second direction.

5. The laser radar according to claim 1, characterized in that: The first end surface and the second end surface are two adjacent end surfaces of the optical path separation module.

6. The laser radar according to claim 1, characterized in that: The first end surface and the second end surface are two opposite end surfaces of the optical path separation module.

7. The laser radar according to claim 5, characterized in that Also includes a second reflection module; The second reflection module is arranged at a side of the optical path separation module having a second end face, the second reflection module has a second reflection surface, the second reflection surface and the second end face are arranged opposite to each other along a fourth direction, the fourth direction is perpendicular to the second end face, the second reflection surface is used to reflect the detection light emitted through the second end face, and along the second direction, the distance between the second reflection surface and the second end face gradually increases or gradually decreases, so that the detection lights reflected by the second reflection surface are arranged at intervals along the fourth direction; Wherein, each of the second micro lenses is arranged opposite to the second reflective surface along the second direction, and each of the second micro lenses is arranged along the fourth direction.

8. The laser radar according to claim 1, characterized in that: The laser radar also includes a third microlens array; The third microlens array is arranged between the optical path separation module and the silicon photonic chip. The third microlens array includes a plurality of third microlenses. Each of the third microlenses corresponds to a light receiving element. The third microlens is used to focus the echo light emitted from the optical path separation module.

9. The laser radar according to claim 1, characterized in that: The light receiving element is a grating, and the length direction of the grating is perpendicular to the second direction.

10. The laser radar according to claim 1, characterized in that: The laser radar also includes a quarter wave plate; The quarter wave plate is disposed between the lenses at the second end surface, and is used to change the linearly polarized detection light into the circularly polarized detection light.

11. The laser radar according to claim 1, characterized in that: The optical path separation module is a polarization beam splitter prism.

12. The laser radar according to any one of claims 1 to 11, characterized in that: The diameters of the first microlens and the second microlens are both less than or equal to 1 mm; The diameter of the lens is less than or equal to 30 mm; The ratio of the diameter of the lens to the diameter of the first microlens is greater than or equal to 10; The ratio of the diameter of the lens to the diameter of the second microlens is greater than or equal to 10.

13. A movable device, characterized in that: include: A movable main body; as well as The laser radar as described in any one of claims 1 to 12 is arranged on the main body.

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