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 reflection module and a silicon optical chip. The light path separation module is provided with a first end surface, a second end surface and a third end surface, the probe light emitted from the second end surface is arranged at intervals along a first direction, and the first direction is parallel to the second end surface; the reflection module is provided with a plurality of first reflection surfaces, each first reflection surface corresponds to one piece of detection light, the first reflection surfaces are used for receiving and reflecting the detection light, the first reflection surfaces are arranged in a staggered mode in the first direction and the second direction, and the second direction is perpendicular to the first direction, so that the multiple pieces of detection light can be arranged in the staggered mode in the first direction and the second direction. Therefore, the resolution of the laser radar is improved, and the detection precision of the laser radar is improved. The silicon optical chip is arranged on the downstream of the third end face in the transmission direction of the echo light, and compared with the technical scheme that an optical fiber is used for being coupled with the silicon optical chip, the coupling energy loss can be reduced.

Description

Technical Field

[0001] The present application relates to the technical field of laser radar, 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 with the silicon photonic chip will produce at least 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 that do not require the use of fiber-coupled silicon photonic chips, thereby reducing coupling energy losses and lowering the requirements 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 reflection module and a silicon photonic chip. 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, the second end face is used to emit detection light and receive echo light, the detection light emitted through the second end face is arranged at intervals along a first direction, the first direction is parallel to the second end face, and the third end face is used to emit echo light, wherein the echo light is formed after the detection light is reflected by the target object. The first reflection module is arranged downstream of the second end face along the transmission direction of the detection light, and has multiple first reflection surfaces, each first reflection surface corresponds to a detection light, and the first reflection surface is used to receive and reflect the detection light. The first reflection surfaces are staggered along the first direction and the second direction, and the second direction is perpendicular to the first direction; the silicon photonic chip is arranged downstream of the third end face along the transmission direction of the echo light, and the silicon photonic chip includes multiple light receiving elements, each light receiving element corresponds to a first reflection surface, and 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 first direction.

[0005] In some embodiments, the first reflection surface and the second end surface are arranged opposite to each other along a second direction, and the second direction is a direction when the detection light is emitted from the second end surface.

[0006] In some embodiments, the first end surface and the second end surface are two adjacent end surfaces of the optical path separation module.

[0007] In some embodiments, the laser radar also includes a second reflection module; the second reflection module is arranged on the side of the optical path separation module having the first end face, the second reflection module has a second reflection surface, and the second reflection surface is used to receive each detection light and reflect it so that the detection light is emitted toward the first end face; the light source module and the silicon photonic chip are both located on the side of the optical path separation module having the third end face.

[0008] In some embodiments, the light receiving element is a receiving waveguide module, and one end of the receiving waveguide module facing the optical path separation module is used to receive the echo light; each receiving waveguide module is arranged along the first direction.

[0009] In some embodiments, the receiving waveguide module includes at least two receiving waveguides, and the two receiving waveguides are spaced apart along the first direction.

[0010] In some embodiments, the laser radar also includes a first microlens array, a second microlens array and a lens, 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 collimate the detection light; the second microlens array is arranged downstream of the first reflection module 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; the 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.

[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 includes multiple 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 polarization beam splitter.

[0012] In some embodiments, the first end surface and the second end surface are two opposite end surfaces of the optical path separation module.

[0013] In some embodiments, the first reflection module also has a third reflection surface; the third reflection surface and the second end surface are arranged relative to each other along the second direction, and the third reflection surface receives the detection light and reflects it; each first reflection surface and the third reflection surface are arranged relative to each other along the second direction, and the first reflection surface is used to receive the detection light signal reflected by the third reflection surface for reflection.

[0014] 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 beams of detection light, and the detection lights are arranged in parallel; each optical amplifier corresponds to a detection light, and the optical amplifier is used to amplify the detection light generated by the laser; the light source includes multiple lasers, the laser is used to generate detection light, and each optical amplifier is arranged 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 signals.

[0015] In some embodiments, the optical path separation module is a polarization beam splitter prism.

[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] Compared with the technical solution of coupling optical fiber with silicon photonic chip, the laser radar of the present application does not need to use optical fiber to couple silicon photonic chip, thereby reducing the energy loss of coupling and lowering the requirement for the maximum output energy of the light source module. 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 a top view structure of a laser radar in one embodiment of the present application;

[0022] Figure 4 This is a schematic diagram of a side view structure of a laser radar in another embodiment of the present application;

[0023] Figure 5 A schematic diagram of a movable device in an embodiment of the present application.

[0024] 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 reflection module; 13A. first reflection surface; 13B. third reflection surface; 14. lens; 15. scanning module; 16. silicon photonic chip; 161. chip body; 162. light receiving element; 17. second reflection module; 17A. second reflection surface; 18. first microlens array; 181. first microlens; 19. second microlens array; 191. second microlens; 20. third microlens array; 201. third microlens; 21. quarter-wave plate; a. detection light; b. echo light; X, first direction; Y, second direction; 2. movable device; 21. main body. DETAILED DESCRIPTION

[0025] 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.

[0026] 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 reflection module 13, a lens 14, a scanning module 15 and a silicon photonic chip 16. Among them, the light source module 11 is used to generate multiple beams of detection light a, and each detection light a is transmitted in parallel. 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. The second end face 12B is used to emit detection light a and receive echo light b. The detection light a emitted through the second end face 12B is arranged at intervals along the first direction X shown in the figure, and the first direction X is parallel to the second end face 12B. The third end face 12C is used to emit echo light b, wherein the echo light b is formed after the detection light a is reflected by the target object. The first reflection module 13 is arranged downstream of the second end surface 12B along the transmission direction of the echo light, and has a plurality of first reflection surfaces 13A, which are used to receive and reflect the detection light a emitted through the second end surface 12B; each first reflection surface 13A corresponds to a detection light a, and each first reflection surface 13A is staggered along the first direction X and the second direction Y, wherein the second direction Y is a direction perpendicular to the first direction X. The silicon photonic chip 16 is arranged downstream of the third end surface 12C along the transmission direction of the echo light b, and the silicon photonic chip 16 includes a plurality of light receiving elements 162, which are used to receive the echo light b emitted through the optical path separation module 12. Each light receiving element 162 corresponds to a first reflection surface 13A, and each light receiving element 162 is arranged at intervals along the first direction X to correspondingly receive the echo light b reflected by each first reflection surface 13A. It should be noted that the "a certain structure corresponds to another structure" in this application document means that the one structure and the other structure are located on the same optical path, that is, the detection light (or echo light) will pass through the one structure and the other structure. Figure 2 The above structures are described in detail.

[0027] For the above light source module 11, please refer to Figure 2 and Figure 3 , which respectively show a side view and a top view of a laser radar provided by one embodiment of the present application, and the light source module 11 is a module for generating detection light a in the laser radar 1. 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 light source 111 to increase the optical power of the detection light a, thereby improving the detection performance of the laser radar 1.

[0028] Please continue to refer to Figure 2 and Figure 3In 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.

[0029] It is understood that in other embodiments of the present application, the light source 111 may also include a laser and a spectrometer; wherein the laser is used to generate a source light signal, and the spectrometer is used to receive the source light signal and split it into multiple beams of detection light a. Compared with the use of multiple lasers, the solution of using a single laser and a spectrometer 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. In addition, the heat generation of the light source module 11 can also be reduced to a certain extent, so that other components used to dissipate heat for the light source 111 can be reduced, which can further reduce the volume and cost of the laser radar 1.

[0030] For the above optical path separation module 12, please continue to 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 output from the light source module 11. The second end face 12B is used to emit the detection light a, and the detection light a emitted through the second end face 12B is arranged at intervals along the first direction X shown in the figure; in addition, the second end face 12B is also used to receive the echo light b. 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 can be a polarization beam splitter prism, which is used to separate the detection light path and the echo light path by polarization beam splitting, wherein the detection light path passes through the optical path separation module 12 in a reflection or transmission manner, and the echo light path passes through the optical path separation module 12 in a transmission or reflection manner accordingly, so that the light source module 11 and the silicon photonic chip 16 can be separately arranged. Furthermore, the solution of coupling the light source module 11 and the silicon photonic chip 16 via optical fiber in the detection light path is avoided, thereby improving the emission efficiency of the detection light a.

[0031] Please continue to refer to Figure 2In 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 splitting film 122. The inclined surfaces of the two right-angle prisms 121 are respectively connected to two opposite surfaces of the polarization beam splitting film 122. The first end face 12A and the second end face 12B can be two adjacent end faces of the optical path separation module 12. Accordingly, the detection light a should be configured to be reflected by the polarization beam splitting film 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 181 and reflect it, so that the reflected detection light a is emitted to the second microlens array 19; at the same time, the polarization beam splitting film 122 is used to transmit the echo light b emitted by the second microlens 191, so that the echo light b transmitted by the polarization beam splitting film 122 is emitted into the silicon photonic chip 16.

[0032] 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 end face 12A, second end face 12B and third end face 12C, and can achieve the separation of the detection optical path and the echo optical 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 components that can achieve the separation of the detection optical path and the echo optical path.

[0033] In order to facilitate the arrangement of the light source module 11 and the silicon photonic chip 16 on the same side of the optical path separation module 12, in this embodiment, the laser radar 1 further includes a second reflection module 17. Figure 2 , the second reflection module 17 is arranged on the side of the optical path separation module 12 having the first end surface 12A, and the second reflection module 17 has a second reflection surface 17A, and the second reflection surface 17A is used to receive the detection light a emitted by the light source module 11 and reflect it to the first end surface 12A. Correspondingly, the light source module 11 can be located on the side of the optical path separation module 12 having the third end surface 12C, that is, the light source module 11 and the silicon photonic chip 16 are located on the same side of the optical path separation module 12. In this way, the transmitting and receiving modules of the laser radar 1 can be optically adjusted on the same side of the optical path separation module 12, which is conducive to simplifying the difficulty of optical adjustment.

[0034] As for the specific structure of the second reflection module 17, it is actually diverse. For example, in the present embodiment, the second reflection module 17 reflects the detection light a by total reflection through the second reflection surface 17A. Specifically, the second reflection module 17 includes a prism having a first side surface, a second side surface and the second reflection surface 17A. Among them, the first side surface is in contact with or opposite to the first end surface 12A; the second side surface is perpendicularly arranged relative to the first side surface, and it is the surface of the prism arranged toward the light source module 11; the second reflection surface 17A is respectively connected to the first side surface and the second side surface, and it is located on the side of the second side surface away from the light source module 11. The second side surface of the prism is used to receive the detection light a generated by the light source module 11, so that the detection light a enters the prism; the second reflection surface 17A is used to reflect the detection light a, so that the detection light a is emitted toward the first side surface, and is emitted from the prism through the first side surface, thereby entering the first end surface 12A. It is understandable that in other embodiments of the present application, the second reflection module 17 may also be other structures such as a reflection mirror, as long as it has the above-mentioned second reflection surface 17A to reflect the detection light a toward the first end surface 12A.

[0035] For the first reflection module 13, please continue to refer to Figure 2 The first reflection module 13 is disposed on the side of the optical path separation module 12 having the second end surface 12B. The first reflection module 13 has a plurality of first reflection surfaces 13A. Figure 2 In the figure, the Figure 3 is obscured and not shown, Figure 3 The "×" mark on the first reflection module 13 in the figure indicates that the echo light is incident on the corresponding first reflection surface 13A. Each first reflection surface 13A corresponds to the above-mentioned detection light a and an optical amplifier, and the first reflection surface 13A is used to reflect the detection light a output by the optical path separation module 12. The first reflection surfaces 13A are staggered along the first direction X and the second direction Y, wherein the second direction Y is perpendicular to the first direction X.

[0036] In this embodiment, the second direction Y is the direction in which the detection light is emitted from the second end face 12B. The first reflection surface 13A and the second end face 12B are arranged relative to each other along the second direction Y, and any two first reflection surfaces 13A are staggered along the first direction X and the second direction Y. In this way, after being reflected by the first reflection module 13, each detection light a will be staggered in the second direction Y, and the detection field of view formed by each detection light a outside the laser radar 1 is stacked and arranged in the second direction Y, thereby forming the total detection field of view of the laser radar 1 in the second direction Y. That is, the setting of multiple detection light paths can improve the total detection field of view of the laser radar 1 along the second direction Y.

[0037] The silicon photonic chip 16 is arranged downstream of the third end face 12C along the transmission direction of the echo light b. The silicon photonic chip 16 includes a chip body 161 and a plurality of light receiving elements 162 arranged on the chip body 161. 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. In this embodiment, the substrate is made of silicon; 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. The light receiving element 162 is arranged in the cladding, which is used to receive the echo light b emitted through the optical path separation module 12; each light receiving element 162 is arranged corresponding to a first reflection surface 13A, and each light receiving element 162 is arranged at intervals along the first direction X to correspondingly receive the echo light b corresponding to each detection light a.

[0038] Please continue to refer to Figure 2 In a specific embodiment, the light receiving element 162 may be a receiving waveguide module, and one end of the receiving waveguide module facing the optical path separation module 12 is used to receive the echo light b. The receiving waveguide modules are arranged along the first direction X and are located in the same layer in the thickness direction of the silicon photonic chip 16; that is, the arrangement direction of the receiving waveguide modules is perpendicular to the thickness direction of the silicon photonic chip 16.

[0039] In addition, the laser radar 1 also includes a scanning module 15 located downstream of the optical path of the first reflection module 13 along the optical path of the detection light a. The scanning module 15 is used to receive the detection light a emitted by the first reflection module 13 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 15 has a fast-axis scanning direction and a slow-axis scanning direction. The fast-axis scanning direction generally corresponds to a direction with a larger field of view, such as the horizontal direction, and the slow-axis scanning direction generally corresponds to a direction with a smaller field of view, such as the vertical direction. In this embodiment, the scanning module 15 may include a galvanometer and / or a rotating mirror, etc., which is not limited in the embodiments of the present application.

[0040] It is worth mentioning that the scanning module 15 is a movable element. When the echo light b returns to the scanning module 15, the scanning module 15 has deflected an angle compared to the emitted detection light a, so that the position where the echo light b falls on the silicon photonic chip 16 is a dot matrix along a specific direction. Among them, with the movement of the scanning module 15, the spot position of the echo light b may change, and the offset 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.

[0041] In this embodiment, the second direction Y is consistent with the slow axis scanning direction, so that the field of view formed by each detection light a outside the laser radar 1 is spliced ​​into a larger detection field of view along the second direction Y, and the detection field of view is the total field of view of the laser radar 1. Correspondingly, the first direction X is the fast axis scanning direction of the laser radar 1. Therefore, during the operation of the laser radar 1, the direction corresponding to the walk-off effect caused by its fast axis scanning is also the first direction X.

[0042] As mentioned above, since the fast axis scanning rate of the laser radar 1 is significantly larger than the slow axis scanning rate, the walk-off effect caused by it is also more obvious; due to the uncertainty of the spot position of the echo light b, the spot may be located outside the receiving waveguide module, so it is necessary to improve this deficiency. In this embodiment, the above-mentioned receiving waveguide module includes at least two receiving waveguides, and the two receiving waveguides are arranged at intervals along the first direction X. When the echo light b deviates from a receiving waveguide along the first direction X due to the walk-off effect, it will move to another adjacent receiving waveguide and be received by the receiving waveguide; therefore, this setting can alleviate the problem of low light receiving coupling efficiency caused by the walk-off effect. It is worth noting that in this embodiment, each receiving waveguide in the same receiving waveguide module is arranged along the first direction X, and each receiving waveguide module is also arranged along the first direction X, and the first direction X is a direction perpendicular to the thickness direction of the silicon photonic chip 16, then all the receiving waveguides are located on the same layer of the silicon photonic chip 16, and this setting is conducive to simplifying the manufacturing process of the silicon photonic chip 16.

[0043] In addition, please refer to Figure 2 In this embodiment, the laser radar 1 also includes a first microlens array 18, a second microlens array 19 and a lens 14. Among them, the first microlens array 18 is located between the light source module 11 and the optical path separation module 12, and the first microlens array 18 is arranged upstream of the first end face 12A along the transmission direction of the detection light a, so as to collimate the above-mentioned detection light a. The second microlens array 19 is located on the side where the first reflection module 13 emits the detection light a, that is, it is arranged downstream of the first reflection module 13, and it is used to focus the detection light a. The lens 14 is located on the side of the second microlens array 19 away from the first reflection module 13, and it is used to collimate the above-mentioned detection light a. Next, combined with Figure 2 The specific structures of the above components are further described in detail.

[0044] The first microlens array 18 is arranged upstream of the first end face 12A along the transmission direction of the detection light a, and the first microlens 181 includes a plurality of first microlenses 181. Each first microlens 181 corresponds to a detection light a, and the first microlens 181 is used to collimate the detection light a. In this embodiment, the first microlens 181 means a lens with a diameter less than or equal to 1 mm. The setting of the first microlens array 18 is intended to achieve collimation of the detection light a while reducing the space occupied in the laser radar 1 to reduce the volume of the laser radar 1.

[0045] The second microlens array 19 is arranged downstream of the first reflection module 13 along the transmission direction of the detection light a, and the second microlens array 19 includes a plurality of second microlenses 191. Each second microlens 191 corresponds to a first microlens 181, and the second microlens 191 is used to focus the detection light a. In this embodiment, the second microlens 191 means a lens with a diameter less than or equal to 1 mm, and the second microlens array 19 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.

[0046] The lens 14 is disposed downstream of the second microlens array 19 along the transmission direction of the detection light a, so as to receive and collimate the detection light a emitted by each second microlens 191. The lens 14 has a first focal plane located on a side close to the second microlens array 19, and the second microlens 191 has a second focal plane located on a side close to the lens 14, and the first focal plane is coplanar with the second focal plane of each second microlens 191.

[0047] In the embodiment of the present application, the first microlens array 18 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 191 can focus the detection light a at the same distance from the first reflection module 13, and make the focal points of each detection light a coplanar; then, each detection light a is further collimated through the same lens 14, and the second microlens 191 cooperates with the lens 14 to expand the detection light a, thereby reducing the divergence angle of the detection light a emitted through the lens 14, which is beneficial to reduce the spot size formed when the detection light a falls on the target object, thereby improving the detection accuracy of the laser radar 1.

[0048] Exemplarily, the diameter of the lens 14 is less than or equal to 30 mm, so that the lens 14 is smaller, thereby reducing the space occupied by the lens 14 in the laser radar 1 to reduce the volume of the laser radar 1.

[0049] Please refer to Figure 2In a specific embodiment, the ratio of the diameter of the lens 14 to the diameter of the first microlens 181 is greater than or equal to 10; the ratio of the diameter of the lens 14 to the diameter of the second microlens 191 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 191 and then diverges, the lens 14 with a larger diameter is more conducive to receiving the diverged detection light a and collimating it; on the other hand, the lens 14 with a larger diameter 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.

[0050] It is worth mentioning that if the light source module 11 is located between the second end face 12B and the third end face 12C of the optical path separation module 12, the distance between the first reflection module 13, the second microlens array 19, the lens 14 and other components and the optical path separation module 12 needs to be appropriately enlarged to avoid interference, which will make the laser radar 1 larger in the second direction Y. The arrangement of the light source module 11 and the silicon photonic chip 16 on the same side of the optical path separation module 12 is conducive to overcoming the above disadvantages.

[0051] In addition, in this embodiment, the laser radar 1 further includes a third microlens array 20. Figure 2 The third microlens array 20 is disposed between the optical path separation module 12 and the silicon photonic chip 16, and includes a plurality of third microlenses 201. Each third microlens 201 corresponds to a light receiving element 162, and the third microlens 201 is used to focus the echo light b emitted from the optical path separation module 12, so that the focused echo light b enters the light receiving element 162. The setting of the third microlens array 20 can improve the efficiency of coupling the echo light b into the silicon photonic chip 16, thereby improving the detection performance of the laser radar 1.

[0052] In addition, in this embodiment, the laser radar 1 may further include a quarter wave plate 21. For details, please refer to Figure 2 , the quarter wave plate 21 is arranged between the first reflection module 13 and the lens 14, and the linearly polarized detection light a is changed into the circularly polarized detection light a by the quarter wave plate 21 for easy detection, and the circularly polarized echo light b can be changed into the linearly polarized echo light b for easy reception; and the polarization directions of the detection light that has not passed through the quarter wave plate 21 and the echo light b 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 through the optical path separation module 12. Since the polarization direction of the echo light b reflected by the target object is mostly the same as the polarization direction of the detection light a before reflection, compared with the case where the quarter wave plate 21 is not arranged, this embodiment can receive more echo light b signals to a certain extent, that is, the reception efficiency of the echo light b signal can be improved.

[0053] In summary, the laser radar disclosed in the embodiment of the present application includes a light source module 11, an optical path separation module 12, a first reflection module 13 and a silicon photonic chip 16. Among them, each detection light a generated by the light source module 11 is sequentially emitted to the outside of the laser radar 1 via the first end face 12A of the optical path separation module 12, the second end face 12B of the optical path separation module 12, and the first reflection surface 13A of the first reflection module 13. Compared with the technical solution of coupling the optical fiber with the silicon photonic chip 16 and emitting the detection light a through the silicon photonic chip 16, the present application does not need to use the optical fiber to couple the silicon photonic chip 16 to emit the detection light through the silicon photonic chip 16, thereby reducing the energy loss of the coupling, reducing the requirement for the maximum output energy of the light source module 11, and thereby reducing the cost of the light source module 11, thereby reducing the cost of the laser radar 1.

[0054] In addition, the detection lights a are staggered along the second direction Y, which is conducive to the fields of view formed by the detection lights a being combined in the second direction Y to form a larger detection field of view, that is, the total field of view of the laser radar 1.

[0055] It is understandable that even though the above-mentioned embodiment is described by taking the first end face 12A and the second end face 12B as two adjacent end faces in the optical path separation module 12, the present application is not limited thereto. In other embodiments of the present application, the first end face 12A and the second end face 12B may also be two opposite end faces of the optical path separation module 12. For example, the optical path separation module 12 still includes a polarization beam splitter prism, and the detection light a is 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 181 and transmit it, so that the transmitted detection light a is emitted to the second microlens array 19; and the polarization beam splitting film 122 is used to reflect the echo light b emitted by the second microlens 191, so that the echo light b reflected by the polarization beam splitting film 122 is emitted into the silicon photonic chip 16.

[0056] It is understandable that, based on the above embodiment, the positions of the light source module 11 and the light receiving element 162 are interchangeable, which can also achieve the purpose of detecting the target object, and will not be elaborated here.

[0057] Finally, it is worth mentioning that regarding the laser radar 1, even though the above embodiment is described by taking the second direction Y as the direction of the detection light a when it is emitted from the second end face 12B, it should be understood that the present application is not limited to this. It is only necessary to ensure that the second direction Y is a direction perpendicular to the first direction X, so that the detection lights a reflected by the first reflecting surface 13A are also staggered along the direction perpendicular to the first direction X (i.e., the second direction Y), so that the field of view formed by each detection light a can be spliced ​​into a larger detection field of view in this direction.

[0058] For example, see Figure 4 , which shows a partial structural schematic diagram of a laser radar 1 provided in some other embodiments of the present application, the laser radar 1 still includes a light source module 11, an optical path separation module 12, a first reflection module 13, a scanning module 15, a silicon photonic chip 16, a second reflection module 17, a first microlens array 18, a second microlens array 19 and a lens 14, which is the same as the above Figure 2 The main differences of the laser radar 1 shown in are: Figure 3 In the laser radar 1 shown, the first reflection module 13 includes a third reflection surface 13B and a plurality of first reflection surfaces 13A.

[0059] Specifically, the third reflection surface 13B is arranged relative to the second end surface 12B along the direction in which the detection light a is emitted from the second end surface 12B (hereinafter referred to as the third direction Z), and is used to receive the detection light a and reflect and deflect it so that the detection light a is reflected along the second direction Y. Each first reflection surface 13A is arranged relative to the third reflection surface 13B along the second direction Y, so as to receive the detection light a reflected by the third reflection surface 13B and emit it in a specific direction; for example, the first reflection surface 13A can be configured to make the reflected detection light a emit along the third direction Z. The first reflection surfaces 13A are staggered with each other along the second direction Y, so that the detection lights a emitted by each first reflection surface 13A are staggered along the second direction Y, thereby facilitating the splicing of multiple detection fields in the second direction Y. It can be understood that the third direction can be parallel to the first direction X or the second direction Y. In the embodiment of the present application, there is no specific limitation on the third direction.

[0060] Similar to the above-mentioned second reflection surface 17A, the present application does not limit the structural form of the first reflection surface 13A and the third reflection surface 13B, as long as they have the function of reflecting the detection light a or the echo light b. For example, the first reflection module 13 may include a reflection mirror group, which realizes the reflection of the light signal by mirror reflection; for another example, the first reflection module 13 may be a light-transmitting medium with a refractive index greater than that of air, which realizes the reflection of the light signal by total reflection at the medium interface.

[0061] Since the slow-axis scanning direction corresponds to the vertical direction of the laser radar 1 , and the second direction Y is consistent with the slow-axis scanning direction, the second direction Y is consistent with the vertical direction of the laser radar 1 . Figure 2 In the laser radar 1, under the condition that each detection light a is staggered along the vertical direction of the laser radar 1, the silicon photonic chip 16 needs to be arranged vertically, which is difficult to assemble and adjust and has low reliability. Figure 3The laser radar 1 shown can realize the horizontal setting of the silicon photonic chip 16 under the condition that each detection light a is staggered along the vertical direction of the laser radar 1, thereby improving the reliability of the silicon photonic chip 16 when being assembled and adjusted inside the laser radar 16.

[0062] Please refer to Figure 5 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.

[0063] 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.

[0064] 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 second end face is used to emit the detection lights and receive the echo lights, the detection lights emitted through the second end face are arranged at intervals along a first direction, the first direction is parallel to the second end face, and the third end face is used to emit the echo lights, wherein the echo lights are formed after the detection lights are reflected by the target object; a first reflection module, disposed downstream of the second end face along the transmission direction of the detection light, having a plurality of first reflection surfaces, each of the first reflection surfaces corresponding to one detection light, the first reflection surface being used to receive and reflect the detection light, the first reflection surfaces being staggered along the first direction and the second direction, the second direction being perpendicular to the first direction; 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 first reflecting surface. 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 first direction.

2. The laser radar according to claim 1, characterized in that The first reflection surface and the second end surface are arranged opposite to each other along the second direction, and the second direction is the direction of the detection light when it is emitted from the second end surface.

3. 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.

4. The laser radar according to claim 3, characterized in that: Also includes a second reflection module; The second reflection module is arranged on a side of the optical path separation module having the first end surface, and the second reflection module has a second reflection surface, and the second reflection surface is used to receive and reflect each of the detection lights so that the detection lights are emitted toward the first end surface; The light source module and the silicon photonic chip are both located on a side of the optical path separation module having a third end surface.

5. The laser radar according to claim 1, characterized in that: The light receiving element is a receiving waveguide module, and one end of the receiving waveguide module facing the optical path separation module is used to receive the echo light; The receiving waveguide modules are arranged along the first direction.

6. The laser radar according to claim 5, characterized in that The receiving waveguide module includes at least two receiving waveguides, and the two receiving waveguides are spaced apart along the first direction.

7. The laser radar according to any one of claims 1 to 6, characterized in that: Also includes: 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 first reflection module 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; as well as 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, wherein the lens has a first focal plane located on a side close to the second microlens array, and 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.

8. The laser radar according to claim 7, 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 includes a plurality of third microlenses. Each third microlens 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 first end surface and the second end surface are two opposite end surfaces of the optical path separation module.

10. The laser radar according to claim 1, characterized in that: The first reflection module also has a third reflection surface; The third reflection surface is arranged opposite to the second end surface along the direction in which the detection light is emitted from the second end surface, and the third reflection surface receives the detection light and reflects it; Each of the first reflecting surfaces is arranged opposite to the third reflecting surface along the second direction, and the first reflecting surface is used to receive the detection light signal reflected by the third reflecting surface for reflection.

11. 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 the optical amplifier is used to amplify the detection light generated by the laser; 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 detection signals.

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

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

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