Laser emission system and lidar system

Abstract

The present application relates to the technical field of optics, and provides a laser emission system and a LiDAR system, so as to solve the problems of poor reliability of laser emission systems, etc. The laser emission system provided in the present application comprises a laser and a microlens array; the laser has a plurality of light emitting portions arranged at intervals in a first direction; the microlens array is configured to receive incident light of the laser, deflect the incident light and then transmit same; the plurality of light emitting portions comprise an M-th light emitting portion and an N-th light emitting portion, and a spatial projection area of the M-th light emitting portion covers a spatial projection area of the N-th light emitting portion, both M and N being positive integers, and a difference value between M and N being less than 5. In the laser emission system provided by the present application, when adverse situations such as failure of the N-th light emitting portion occur, a light beam generated by the M-th light emitting portion can effectively compensate for the N-th light emitting portion, thereby enabling the entire laser emission system to still achieve good performance, and also effectively improving the uniformity of light emission.

Description

A laser emission system and a laser radar system TECHNICAL FIELD

[0001] The present application relates to the field of optical technology, and in particular to a laser emission system and a laser radar system. BACKGROUND

[0002] With the development of automatic driving technology, there is a higher and higher requirement for the ability of vehicles to perceive the surrounding environment. As an important part of vehicles for perceiving the surrounding environment, the laser emission system plays a very important role.

[0003] At present, in order to improve the performance of the laser emission system, a laser capable of emitting multiple laser beams is usually used. In actual application, under the influence of factors such as manufacturing process or use environment, some beams may fail, resulting in a decrease in the uniformity of the emitted beams. Even it may cause the loss of target detection and other adverse conditions. Therefore, how to avoid the performance decline caused by beam failure has become a technical problem to be solved.

[0004] SUMMARY

[0005] The present application provides a laser emission system and a laser radar system which can effectively improve the problem of beam failure.

[0006] In a first aspect, the present application provides a laser emission system, comprising a laser and a microlens array. The laser has a plurality of light emitting parts arranged at intervals along a first direction, and the microlens array is used to receive incident light of the laser and to transmit exit light after deflection processing of the incident light. Wherein, along the first direction, the plurality of light emitting parts includes an Mth light emitting part and an Nth light emitting part. The projection area of the Mth light emitting part in space covers the projection area of the Nth light emitting part in space. Wherein, M and N are positive integers, and the difference between M and N is less than 5. In the laser emission system provided by the present application, when some light emitting parts fail or have other adverse conditions, the light beams generated by other light emitting parts can effectively compensate for the failure of the light emitting parts. Therefore, the entire laser emission system can still have good performance. In addition, by configuring the microlens array, the light emission uniformity of the entire laser emission system can be effectively improved, so that the entire laser emission system has good working performance.

[0007] Alternatively, it can be understood that in the laser emission system provided by the present application, along the first direction, the reverse extension line of the exit light generated by the incident light of the Mth light emitting part after the microlens array processing passes through the Nth light emitting part. According to the principle of straight-line propagation of light, the exit light received by the target surface can be considered to be emitted by the Nth light emitting part. Therefore, when the Nth light emitting part fails or has other adverse conditions, the laser beam generated by the Mth light emitting part can effectively compensate for the Nth light emitting part.

[0008] In an example, the laser includes a plurality of light sources. In the first direction, the laser includes a plurality of light emitting regions, each of which includes a plurality of light emitting parts. Among them, the number of light sources is the same as and one-to-one corresponds to the number of light emitting regions, and the laser emitted by each light source is emitted through the light emitting part in the corresponding light emitting region. In general, the laser has the function of emitting light in different regions. In actual application, different regions in space can be illuminated by controlling different light emitting regions of the laser emitting system to improve the ability of regional detection.

[0009] In addition, in the laser emitting system provided in the present application, the projection area of the Mth light emitting part in the first direction covers the projection area of the Nth light emitting part in space, and the difference between M and N is less than 5. Therefore, in actual application, the transition zone of the light spot between different regions is small, which is beneficial to balance light compensation and regional light control.

[0010] In a specific arrangement, in the first direction, the microlens array includes a plurality of lens units. The distance between two adjacent light emitting parts is D1, and the aperture of the light emitting part is L1. The distance between two adjacent lens units is D2, and the aperture of the lens unit is L2. Among them, D2=L2, and D2 is greater than 2(D1+L1). By reasonably controlling the distance between the lens units, the aperture of the lens unit, the aperture of the light emitting part and the distance between the light emitting parts, the projection area of the Mth light emitting part in the first direction can cover the projection area of the Nth light emitting part in space, and the difference between M and N is less than 5. That is, the laser emitting system can effectively balance light compensation and regional light emission.

[0011] In an example, in the first direction, the microlens array includes a plurality of lens units, and the focal length of each lens unit is F. The distance between the laser and the microlens array is Ld, wherein Ld is greater than 2F. Alternatively, it can be understood that in a specific arrangement, the focal length (or optical power) of the lens unit and the distance between the laser and the microlens array can also be reasonably arranged, so that the laser emitting system can effectively balance light compensation and regional light emission.

[0012] In an example, the laser further includes a plurality of light emitting parts arranged in the second direction, and the second direction is perpendicular to the first direction. Among them, in the second direction, the back extension line of the outgoing light generated by the microlens array processing of the incident light of any light emitting part passes through the light emitting part. Alternatively, it can be understood that in the second direction, the microlens array does not perform deflection processing on the light beam, so as to facilitate collimation and other processing of the light beam.

[0013] In an example, the microlens array includes a first surface and a second surface facing away from each other, the first surface is a plane, the second surface includes a plurality of lens units arranged in the first direction, and each lens unit is a convex lens.

[0014] In a specific arrangement, the microlens array is fixedly connected with the laser, so as to effectively improve the integration of the laser emission system.

[0015] In an example, the laser emission system further comprises a collimating lens group. The collimating lens group is located on the light emitting side of the microlens array, and each of the plurality of light emitting parts is located on the focal plane of the collimating lens group. The collimating lens group is configured to collimate the emitted light transmitted by the microlens array, so as to improve the projection accuracy and distance of the laser beam.

[0016] In an example, the collimating lens group comprises a lens barrel and at least one lens fixed in the lens barrel, and the microlens array is fixed in the lens barrel, so as to improve the integration of the laser emission system.

[0017] In a second aspect, the application further provides a laser radar system comprising the laser emission system and a laser receiving system. The laser emission system is configured to project a laser beam into space, and the laser receiving system is configured to receive the laser beam reflected by an object in space, so as to realize the function of detection. In the laser radar system provided by the application, the laser emission system is equipped, so as to effectively improve the stability and reliability of the laser radar system. BRIEF DESCRIPTION OF DRAWINGS

[0018] FIG. 1 is a schematic diagram of an application scenario of a laser radar system according to an embodiment of the application;

[0019] FIG. 2 is a structural block diagram of a laser radar system according to an embodiment of the application;

[0020] FIG. 3 is a structural diagram of a conventional laser emission system according to an embodiment of the application;

[0021] FIG. 4 is a structural diagram of a laser emission system according to an embodiment of the application;

[0022] FIG. 5 is a structural diagram of a part of a laser emission system according to an embodiment of the application;

[0023] FIG. 6 is a structural diagram of a part of a laser emission system according to an embodiment of the application;

[0024] FIG. 7 is a structural diagram of a part of a laser emission system according to an embodiment of the application;

[0025] FIG. 8 is a structural diagram of a part of a laser emission system according to an embodiment of the application;

[0026] FIG. 9 is a simulation diagram of the light intensity distribution of a display target surface according to an embodiment of the application;

[0027] FIG. 10 is a simulation diagram of light intensity distribution of a display target surface provided by an embodiment of the present application;

[0028] FIG. 11 is a simulation diagram of light intensity distribution of a display target surface provided by an embodiment of the present application;

[0029] FIG. 12 is a simulation diagram of light intensity distribution of another display target surface provided by an embodiment of the present application;

[0030] FIG. 13 is a plan view of a light emitting surface provided by an embodiment of the present application;

[0031] FIG. 14 is a structural diagram of a laser emitting system without a microlens array provided by an embodiment of the present application;

[0032] FIG. 15 is a structural diagram of a laser emitting system provided by an embodiment of the present application;

[0033] FIG. 16 is a structural diagram of a part of a laser emitting system provided by an embodiment of the present application;

[0034] FIG. 17 is a plan view of another light emitting surface provided by an embodiment of the present application;

[0035] FIG. 18 is a structural diagram of another laser emitting system provided by an embodiment of the present application;

[0036] FIG. 19 is a structural block diagram of a laser radar system provided by an embodiment of the present application. DETAILED DESCRIPTION

[0037] In order to make the purpose, technical solutions and advantages of the present application clearer, the present application will be described in further detail below with reference to the drawings.

[0038] In order to facilitate understanding of the laser emitting system and the laser radar system provided by the embodiments of the present application, the application scenarios thereof will be introduced first below.

[0039] As shown in FIG. 1, the laser radar system 01 provided by an embodiment of the present application can be applied in a vehicle 02 to enable the vehicle 02 to have the ability of environmental perception. That is, through the laser radar system 01, the vehicle 02 can detect and identify a target object 03 or the environment in which the vehicle 02 is located, thereby assisting the driver to drive the vehicle to improve the safety during driving. Or, some vehicles 02 can also rely on the laser radar system 01 to realize a higher level of automatic driving capability.

[0040] As shown in FIG. 2, the laser radar system 01 mainly includes a laser emitting system 011 and a laser receiving system 012. The laser emitting system 011 is used to emit laser beams to the outside environment. When the laser beams are projected to the target object 03 (such as road, pedestrian, vehicle, etc.), the laser beams will be reflected. The laser receiving system 012 receives the reflected laser beams to achieve the purpose of detecting and identifying the road conditions or environment.

[0041] With the development of automatic driving technology, there is a higher and higher requirement for the ability of the vehicle 02 to perceive the surrounding environment. At present, the ability of the vehicle 02 to perceive can be improved by increasing the number of beams emitted by the laser emitting system 011.

[0042] For example, as shown in FIG. 3, in an example provided by the present application, a structural schematic diagram of a laser emitting system 011 is shown. The laser emitting system 011 is specifically a vertical cavity surface emitting laser (VCSEL). In simple terms, the vertical cavity surface emitting laser includes a light source 0111 and a light emitting surface 0112, and the light emitting surface 0112 has a plurality of through holes 01121 (three are shown in FIG. 3). The dotted arrows in FIG. 3 show the approximate propagation path of the light beams. The laser emitted by the light source 0111 can be transmitted through the through holes 01121 to be emitted outward, thereby forming a plurality of laser beams, and finally being projected to the target object 03. In actual application, the aperture of the through hole 01121 is small, generally in the order of tens of microns. During production, there may be bad points and other bad conditions, so that some through holes 01121 cannot effectively transmit the light beams, or the transmitted light beams have low light intensity. In addition, when dust and other impurities in the outside environment fall into the through hole 01121, the through hole 01121 may be blocked, resulting in some through holes 01121 cannot effectively transmit the light beams, or the transmitted light beams have low light intensity. Therefore, the light intensity received by different regions of the target object 03 will have obvious differences, and it is easy to appear inaccurate identification and even detection loss and other bad conditions.

[0043] At present, in order to reduce the problems such as failure of the through hole 01121, usually the manufacturing process and manufacturing environment are strengthened. For example, in terms of manufacturing process, the through hole 01121 is usually manufactured by using a preparation method with high precision, so as to reduce the problems such as failure of the through hole 01121 as much as possible. However, this method will obviously increase the manufacturing cost and difficulty, which is not conducive to wide application, and also cannot completely guarantee that each through hole 01121 will not fail. In addition, in terms of manufacturing environment, dust-free production and assembly are usually strengthened to avoid dust and other impurities from blocking the through hole 01121. However, this method will also obviously increase the manufacturing cost. Therefore, how to effectively improve the performance of the laser emission system 011 has become a technical problem to be solved.

[0044] Based on this, the embodiment of the present application provides a laser emission system which can effectively improve the problem of beam failure.

[0045] In order to make the purpose, technical scheme and advantages of the present application more clear, the present application will be further described in detail below with reference to the drawings and specific embodiments.

[0046] As shown in FIG. 4, in an example provided by the present application, the laser emission system 10 includes a laser 11 and a micro lens array 12 (MLA). The laser 11 includes a light source 111 and an out-light surface 110 for transmitting a plurality of light beams. The light source 111 is used to generate a laser beam and transmit a plurality of light beams outward through the out-light surface 110. In the example provided by the present application, the out-light surface 110 has a plurality of light emitting parts (three are shown in FIG. 4), which are light emitting part 1101a, light emitting part 1101b and light emitting part 1101c. The plurality of light emitting parts are arranged in a first direction on the out-light surface 110, wherein the first direction is parallel to the out-light surface 110. The laser generated by the light source 111 can be transmitted outward from the plurality of light emitting parts, thereby generating a plurality of laser beams. The micro lens array 12 faces the out-light surface 110, and the micro lens array 12 is used to receive the laser beams transmitted by the light emitting parts and transmit the laser beams after deflection processing.

[0047] In addition, in the example provided by the present application, along the first direction, the out-light surface 110 includes the Mth light emitting part and the Nth light emitting part. The projection area of the Mth light emitting part in space covers the projection area of the Nth light emitting part in space, wherein M and N are both positive integers, and the difference between M and N is less than 5.

[0048] For the convenience of understanding, first, taking the out-light surface 110 including three light emitting parts and the difference between M and N being 1 as an example for illustrative description.

[0049] Specifically, as shown in FIG. 5, in the examples provided in the present application, three light emitting parts are shown, which are light emitting part 1101a, light emitting part 1101b and light emitting part 1101c. The light emitting part 1101a, light emitting part 1101b and light emitting part 1101c are arranged at intervals along the first direction. That is, in the first direction, the light emitting part 1101a is the first light emitting part, the light emitting part 1101b is the second light emitting part, and the light emitting part 1101c is the third light emitting part.

[0050] In FIG. 5, the dashed arrows represent the approximate propagation path of the laser beams emitted from the light emitting part 1101a, light emitting part 1101b and light emitting part 1101c without the microlens array 12. As can be clearly seen from FIG. 5, without the microlens array 12, the projection area of the laser beams emitted from the light emitting part 1101a on the target surface 001 is 001a, the projection area of the laser beams emitted from the light emitting part 1101b on the target surface 001 is 001b, and the projection area of the laser beams emitted from the light emitting part 1101c on the target surface 001 is 001c.

[0051] In addition, in FIG. 5, the solid arrows represent the approximate propagation path of the laser beams emitted from the light emitting part 1101b after the microlens array 12 is arranged. As can be clearly seen from FIG. 5, after the microlens array 12 is arranged, the projection area of the laser beams emitted from the light emitting part 1101b on the target surface 001 covers 001a, 001b and 001c. That is, along the first direction, the projection area of the second light emitting part in space covers the projection areas of the first and third light emitting parts in space.

[0052] Therefore, when the light emitting part 1101a or light emitting part 1101c has a failure or other adverse conditions, the light beams generated by the light emitting part 1101b can effectively compensate for the light emitting part 1101a and light emitting part 1101c, so that the entire laser emitting system 10 can still have good performance.

[0053] In addition, as shown in FIG. 6, FIG. 6 also shows the approximate propagation path of some other laser beams generated by the light emitting part 1101b. Among them, in order to facilitate distinction and understanding, in the following examples, the laser beams emitted by the light emitting part are defined as incident light, and the laser beams emitted by the microlens array 12 are defined as outgoing light. That is, the microlens array 12 is used to receive the incident light of the light emitting part and to fold the incident light to emit outgoing light.

[0054] The propagation path of some light is changed after the incident light of the light emitting part 1101b is processed by the microlens array 12, and is transmitted to the target surface 001. As an example, three incident lights are shown in FIG. 6, which are incident light S1, incident light S2 and incident light S3. Among them, the incident light S1 is basically consistent with the principal axis of the microlens array 12, so that the propagation path of the incident light S1 is basically unchanged after the microlens array 12, and the transmitted light S11 is transmitted. The incident light S2 is processed by the microlens array, and the propagation path is deflected, and the transmitted light S21 is transmitted. The incident light S3 is processed by the microlens array, and the propagation path is deflected, and the transmitted light S31 is transmitted. In addition, S20 is the reverse extension line of the transmitted light S21, and the reverse extension line S20 passes through the light emitting part 1101a. S30 is the reverse extension line of the transmitted light S31, and the reverse extension line S30 passes through the light emitting part 1101c. Among them, the reverse extension line of the transmitted light S11 is basically coincident with the incident light S1, so it is not shown in FIG. 6. That is, the reverse extension line of the transmitted light S11 passes through the light emitting part 1101a. According to the straight line propagation principle of light, the transmitted light S21 received by the target surface 001 can be considered to be emitted by the light emitting part 1101a. Correspondingly, the transmitted light S31 received by the target surface 001 can be considered to be emitted by the light emitting part 1101c. Therefore, when the light emitting part 1101a or the light emitting part 1101c fails or has other adverse conditions, the light beam generated by the light emitting part 1101b can effectively compensate for the light emitting part 1101a and the light emitting part 1101c. Therefore, the entire laser emitting system 10 can still have good performance.

[0055] In addition, in actual application, the area between the two adjacent light emitting parts is a non-light transmission area. In the examples provided in the present application, the incident light of the light emitting part can be reasonably deflected and transmitted by the microlens array 12 to make the light intensity received by the target object have good uniformity.

[0056] For example, as shown in FIG. 7, FIG. 7 shows the approximate propagation path of some other laser beams generated by the light emitting part 1101b. As an example, FIG. 7 shows two incident lights, incident light S4 and incident light S5. Among them, the incident light S4 passes through the microlens array 12, the propagation path is deflected, and the transmitted light S41 is transmitted. The incident light S5 passes through the microlens array 12, the propagation path is deflected, and the transmitted light S51 is transmitted. In addition, S40 is the reverse extension line of the transmitted light S41, and the reverse extension line S40 passes through the non-light-transmitting area between the light emitting part 1101a and the light emitting part 1101b. S50 is the reverse extension line of the transmitted light S51, and the reverse extension line S50 passes through the non-light-transmitting area between the light emitting part 1101b and the light emitting part 1101c. According to the straight-line propagation principle of light, the transmitted light S41 received by the target surface 001 can be considered to be emitted by the non-light-transmitting area between the light emitting part 1101a and the light emitting part 1101b. Correspondingly, the transmitted light S51 received by the target surface 001 can be considered to be emitted by the non-light-transmitting area between the light emitting part 1101b and the light emitting part 1101c. Therefore, by being equipped with the microlens array 12, the target surface 001 can receive a surface light source with relatively uniform light intensity. That is, the microlens array 12 can improve the uniformity of the light spot, thereby reducing the adverse problems such as algorithm ranging accuracy decline or jitter caused by the pitting effect of the laser 11.

[0057] In summary, the reverse extension line of the transmitted light of the light beam generated by the light emitting part 1101b can not only pass through the light emitting part 1101a, the light emitting part 1101b and the light emitting part 1101c, but also pass through the non-light-transmitting area between the light emitting part 1101a and the light emitting part 1101b and the non-light-transmitting area between the light emitting part 1101b and the light emitting part 1101c. That is, the reverse extension line of the transmitted light of the light emitting part 1101b passes through the area where the light emitting part 1101a, the light emitting part 1101b and the light emitting part 1101c are located. Therefore, the adverse conditions such as local light intensity being weak and target detection being lost caused by the failure of the light emitting part 1101a or the light emitting part 1101c can be effectively improved. In addition, the light emitting uniformity of the entire laser 11 can be effectively improved, so that the entire laser emitting system 10 has good working performance.

[0058] It should be noted that in the above examples, the exemplary description is taken as the light emitting part 1101b. In actual application, the reverse extension line of the light beam generated by the light emitting part 1101a can also pass through the light emitting part 1101b and the non-light-transmitting area between the light emitting part 1101a and the light emitting part 1101b. Correspondingly, the reverse extension line of the light beam generated by the light emitting part 1101c can also pass through the light emitting part 1101b and the non-light-transmitting area between the light emitting part 1101b and the light emitting part 1101c. In summary, in the first direction, the reverse extension line of the exit light generated by the incident light of the Mth light emitting part after the deflection processing of the microlens array 12 passes through the Nth light emitting part. Wherein, the difference between M and N is 1.

[0059] It can be understood that in the above examples, the exemplary description is taken as the difference between M and N being 1. In actual application, the difference between M and N can also be any value in 2, 3 or 4. When the difference between M and N is larger, the deflection angle of the microlens array 12 to the light beam generated by a single light emitting part is also larger, and the reverse extension line of the exit light corresponding to the light emitting part can also pass through more light emitting parts. That is, the projection area of the light emitting part in space can cover the projection area of more light emitting parts in space. Therefore, the fault tolerance of the light emitting part failure is also larger. That is, when the adjacent two, three or four light emitting parts of the light emitting part all have failure or other adverse conditions, the light emitting part can still effectively compensate for the failure of the light emitting part, and the robustness of the entire laser 11 can be improved.

[0060] For example, as shown in FIG. 8, in another example provided by the present application, six light emitting parts are shown, which are light emitting part 1101a, light emitting part 1101b, light emitting part 1101c, light emitting part 1101d, light emitting part 1101e and light emitting part 1101f. The light emitting part 1101a, the light emitting part 1101b, the light emitting part 1101c, the light emitting part 1101d, the light emitting part 1101e and the light emitting part 1101f are arranged in the first direction. That is, in the first direction, the light emitting part 1101a is the first light emitting part, the light emitting part 1101b is the second light emitting part, the light emitting part 1101c is the third light emitting part, the light emitting part 1101d is the fourth light emitting part, the light emitting part 1101e is the fifth light emitting part, and the light emitting part 1101f is the sixth light emitting part.

[0061] In FIG. 8, the dashed arrows represent the approximate propagation path of the laser beams emitted from the six light emitting portions without the microlens array 12. As can be clearly seen from FIG. 8, the laser beam emitted from the light emitting portion 1101a projects onto the target surface 001 in the area 001a, the laser beam emitted from the light emitting portion 1101b projects onto the target surface 001 in the area 001b, the laser beam emitted from the light emitting portion 1101c projects onto the target surface 001 in the area 001c, and the laser beam emitted from the light emitting portion 1101d projects onto the target surface 001 in the area 001d.

[0062] In the case where both the light emitting portion 1101e and the light emitting portion 1101f are functioning normally, the laser beam emitted from the light emitting portion 1101e projects onto the target surface 001 in the area 001e, and the laser beam emitted from the light emitting portion 1101f projects onto the target surface 001 in the area 001f.

[0063] In the example provided in FIG. 8, both the light emitting portion 1101e and the light emitting portion 1101f are malfunctioning, and thus, neither the area 001e nor the area 001f receives a valid beam.

[0064] In FIG. 8, the solid arrows represent the approximate propagation path of the laser beam emitted from the light emitting portion 1101b after the microlens array 12 is provided. As can be clearly seen from FIG. 8, the laser beam emitted from the light emitting portion 1101b projects onto the target surface 001 in the areas 001a, 001b, 001c, 001d, 001e and 001f after the microlens array 12 is provided. That is, in the first direction, the projection area of the second light emitting portion covers the projection area of the sixth light emitting portion. In general, the projection area of the Mth light emitting portion covers the projection area of the Nth light emitting portion, where the difference between M and N is 4.

[0065] Therefore, when the light emitting portion 1101e or the light emitting portion 1101f malfunctions, the light beam generated by the light emitting portion 1101b can effectively compensate for the light emitting portion 1101e and the light emitting portion 1101f, and thus, the entire laser emitting system 10 can still have good performance.

[0066] In addition, as shown in FIG. 9, FIG. 9 shows the light intensity distribution of the beams emitted from the laser emitting system 10 in FIG. 8 on the target surface 001 without the microlens array 12. As can be clearly seen from FIG. 9, the light intensity in the areas 001e and 001f is almost zero.

[0067] As shown in FIG. 10, FIG. 10 shows a simulation diagram of the light intensity distribution of the light beam transmitted by the laser emitting system 10 in FIG. 8 on the target surface 001 when the microlens array 12 is not arranged. In FIG. 10, the horizontal axis represents different regions on the target surface 001, and the vertical axis represents the light intensity. As can be seen from FIG. 9, the light intensity of the regions 001e and 001f is almost zero.

[0068] In addition, as shown in FIG. 11, FIG. 11 shows a simulation diagram of the light intensity distribution of the light beam transmitted by the laser emitting system 10 in FIG. 8 on the target surface 001 when the microlens array 12 is arranged. As can be seen from FIG. 11, the regions 001e and 001f have obvious light intensity.

[0069] As shown in FIG. 12, FIG. 12 shows a simulation diagram of the light intensity distribution of the light beam transmitted by the laser emitting system 10 in FIG. 8 on the target surface 001 when the microlens array 12 is arranged. In FIG. 12, the horizontal axis represents different regions on the target surface 001, and the vertical axis represents the light intensity. As can be seen from FIG. 12, the regions 001e and 001f have obvious light intensity.

[0070] In summary, it can be seen from FIG. 12 in FIG. 8 that when the light emitting part 1101d and the light emitting part 1101e are invalid, the regions on the target surface 001 corresponding to the light emitting part 1101d and the light emitting part 1101e still have effective light intensity. Therefore, after the microlens array 12 is arranged in the laser emitting system 10, the problem of detection loss and other adverse problems can be effectively prevented.

[0071] In addition, in the above examples, the light emitting surface 110 includes six light emitting parts as an example for illustrative explanation. In actual application, the light emitting surface 110 can include more light emitting parts.

[0072] For example, as shown in FIG. 13, in another example provided by the present application, the light emitting surface 110 includes 16 light emitting parts 1101, and the 16 light emitting parts 1101 are arranged along the first direction at the same interval. In addition, the laser 11 provided by the embodiments of the present application also has the effect of partitioned light striking.

[0073] Specifically, as shown in FIG. 14, the laser 11 includes four light sources, i.e., a light source 111a, a light source 111b, a light source 111c, and a light source 111d. The 16 light emitting portions 1101 are divided into four light transmission regions, i.e., a light transmission region A1, a light transmission region A2, a light transmission region A3, and a light transmission region A4. Each of the light transmission regions includes four light emitting portions 1101. Each of the light transmission regions corresponds to one light source, and the light intensity of the light emitted from each of the light transmission regions is substantially the same. For example, the laser generated by the light source 111a is emitted outward by the four light emitting portions 1101 in the light transmission region A1, and is not emitted outward by the light emitting portions 1101 in the other light transmission regions. Alternatively, only a small amount of the light beam generated by the light source 111a is emitted outward from the other light transmission regions. When the light is emitted in the partitioned manner, the corresponding light source can be turned on or turned off to illuminate different regions of the target surface 001. For example, the solid arrows in FIG. 14 show the approximate paths of the light beams generated by the four light sources and transmitted through the four light transmission regions to the target surface 001. As shown in FIG. 14, the illumination regions of the light beams generated by different light sources on the target surface 001 are different. In addition, the illumination regions of the lasers generated by two adjacent light sources on the target surface 001 overlap in a large area. That is, the light beams emitted by the adjacent two light transmission regions on the target surface 001 have a wide light spot transition zone, and the effect of the partitioned illumination is weak.

[0074] In the examples provided in the present application, the light spot transition zone can be obviously reduced by being provided with the microlens array 12, so that a better partitioned illumination effect can be achieved.

[0075] Specifically, as shown in FIG. 15, in the examples provided in the present application, the solid arrows show the approximate paths of the light beams generated by the four light sources 111 and transmitted through the four light transmission regions and the microlens array 12 to the target surface 001. As shown in FIGS. 14 and 15, the illumination regions of the light beams generated by different light sources on the target surface 001 are different. In addition, the illumination regions of the lasers generated by two adjacent light sources 111 on the target surface 001 overlap in a small area. That is, the light beams emitted by the adjacent two light transmission regions on the target surface 001 have a narrow light spot transition zone, and the effect of the partitioned illumination can be improved.

[0076] In summary, in the examples provided in the present application, the difference between M and N is limited to less than 5, which not only can achieve the functions of light intensity homogenization and compensation, but also can avoid the obvious influence of the light energy between different partitions, and a better partitioned illumination effect can be achieved.

[0077] In actual applications, the aperture of the light emitting portion 1101, the distance between two adjacent light emitting portions 1101, the focal power of the microlens array 12, the distance between the light emitting surface 110 and the microlens array 12, and the like can be reasonably set so that the projection area of the Mth light emitting portion 1101 in space covers the projection area of the Nth light emitting portion 1101 in space along the first direction. M and N are both positive integers, and the difference between M and N is less than 5.

[0078] For ease of understanding, the structure of the laser 11 and the microlens array 12 will be exemplarily described below.

[0079] In a specific setting, the laser 11 can be a vertical cavity surface emitting laser (VCSEL). The light source described above is specifically a semiconductor light emitting device in the vertical cavity surface emitting laser, and the light emitting surface 110 is a surface for transmitting light in the vertical cavity surface emitting laser. In addition, the light emitting portion 1101 can be a via hole prepared by an oxidation process or the like. In specific applications, a currently commonly used vertical cavity surface emitting laser can be selected as the laser 11, and the present application will not be repeated. Of course, in other examples, the laser 11 can also use other types of lasers with light sources and light emitting surfaces, and the present application does not limit the specific type of the laser 11.

[0080] In addition, as shown in FIG. 16, the microlens array 12 includes a first surface 121 and a second surface (not shown in FIG. 16) facing away from each other. The first surface 121 is a plane, and the second surface includes a plurality of lens units 122 arranged along the first direction. Specifically, the lens units 122 are all convex lenses. The direction of propagation of the laser beam will be deflected after passing through the lens units 122. The distance between two adjacent lens units 122 and the radius of curvature of the lens units can both be controlled to be in the micrometer level, so that the microlens array 12 has a large tolerance tolerance, which is beneficial to realize the blind mounting between the microlens array 12 and the laser 11, and ensures the beam quality. In a specific setting, the material of the microlens array 12 can be quartz, sapphire, glass, or polymer, etc. The specific material and preparation process of the microlens array 12 are selected and prepared according to the current common method, and the present application does not limit this. In addition, in a specific setting, the lens units 122 can be located on the second surface or on the first surface. In actual applications, the layout position, number, curvature (or focal power) and the like of the lens units 122 can be reasonably set according to actual needs.

[0081] For example, as shown in FIG. 16, in an example provided by the present application, along the first direction, the distance between two adjacent light emitting portions 1101 is D1, and the aperture of the light emitting portion 1101 is L1. In addition, along the first direction, the distance between two adjacent lens units 122 is D2, and the aperture of the lens unit 122 is L2. Wherein, D2 is approximately equal to L2, and D2 is greater than 2(D1+L1). By reasonably controlling the distance D2 between the lens units 122, the aperture L2 of the lens unit 122, the aperture L1 of the light emitting portion 1101 and the distance D1 between the light emitting portions 1101, the projection area of the Mth light emitting portion 1101 in the first direction can be covered to the projection area of the Nth light emitting portion 1101 in space, and the difference between M and N is less than 5. That is, the laser emitting system 10 can effectively balance the light compensation and zoned light emission.

[0082] In addition, in actual application, the focal length F (or optical power) of the lens unit 122 can also be reasonably set. For example, along the first direction, the focal length of each lens unit 122 can be F, and the distance between the laser 11 and the microlens array 12 is Ld, wherein Ld is greater than 2F. It should be noted that the distance Ld between the laser 11 and the microlens array 12 is specifically the distance between the light emitting surface 110 and the second surface of the microlens array 12.

[0083] In summary, in actual application, the above-mentioned parameters can be reasonably set according to actual needs, so that the laser emitting system 10 can effectively balance the light compensation and zoned light emission.

[0084] In addition, in the above example, the light emitting surface 110 includes a plurality of light emitting portions 1101, and the plurality of light emitting portions 1101 are arranged only along the first direction. In other examples, the plurality of light emitting portions 1101 can also be arranged along other directions parallel to the light emitting surface 110.

[0085] For example, as shown in FIG. 17, in another example provided by the present application, the plurality of light emitting portions 1101 in the light emitting surface 110 are arranged not only along the first direction, but also along the second direction. Wherein, the first direction is perpendicular to the second direction, and both the first direction and the second direction are parallel to the light emitting surface 110.

[0086] In addition, in the examples provided in the present application, in the second direction, the back prolongation line of the emergent light generated by the micro-lens array 12 processing the incident light of any light emitting part 1101 passes through the light emitting part 1101. That is, in the second direction, the micro-lens array 12 does not perform deflection processing on the propagation path of the light. Alternatively, it can be understood that the lens units in the micro-lens array 12 only have optical power in the first direction, so that the light rays can be deflected in the first direction after passing through the micro-lens array 12. The micro-lens array 12 has no optical power in the second direction, so that the light rays will not be deflected in the second direction after passing through the micro-lens array 12.

[0087] Alternatively, in other examples, in the second direction, the micro-lens array 12 can also perform deflection processing on the incident light of the light emitting part 1101.

[0088] For example, after the incident light of the light emitting part 1101 is deflected by the micro-lens array 12 to emit emergent light, the back prolongation line of the emergent light can pass through the non-light-transmitting area around the light emitting part 1101 without covering other light emitting parts 1101, so that the micro-lens array 12 can achieve a slight light uniformization effect on the light emitting part 1101.

[0089] Alternatively, in other examples, after the incident light of the light emitting part 1101 is deflected by the micro-lens array 12 to emit emergent light, the back prolongation line of the emergent light can pass through the first, second, third or fourth light emitting part 1101 adjacent to the light emitting part 1101. That is, the micro-lens array 12 has optical power in the first direction and the second direction, so that the micro-lens array 12 can perform deflection processing on the light rays of the light emitting part 1101 in two dimensions of the first direction and the second direction.

[0090] In addition, in specific settings, other optical elements can also be included in the laser emitting system 10.

[0091] For example, as shown in FIG. 18, in another example provided in the present application, the laser emitting system 10 further includes a collimating mirror group 13. The collimating mirror group 13 is located on the light emitting side of the micro-lens array 12, and is used to collimate the emergent light emitted by the micro-lens array 12. That is, the divergent emergent light will be converted into a parallel light beam after passing through the collimating mirror group 13. By setting the collimating mirror group 13, the directionality of the laser beam can be effectively improved, which is beneficial to improve the light intensity received by the target surface, thereby ensuring the performance of the laser emitting system 10.

[0092] The light exit surface 110 of the laser 11 can be located on the focal plane of the collimating lens group 13, that is, the light exit surface 110 is substantially coincident with the focal plane of the collimating lens group 13, or there can be a small size deviation between the light exit surface 110 and the focal plane. The focal plane of the collimating lens group 13 is also called the front focal plane or the object focal plane. In the examples provided in the present application, after the light exit surface 110 of the laser 11 is substantially coincident with the focal plane of the collimating lens group 13, the collimating lens group 13 can effectively collimate the light beams emitted by each light exit portion 1101, so that the laser emitting system 10 has better light beam output performance.

[0093] In a specific arrangement, the collimating lens group 13 can include a sleeve 131 and a plurality of lenses 132 located in the sleeve 131. The plurality of lenses 132 are arranged in sequence along the main optical axis and perform folding processing on the light rays, so that the divergent light beams can be collimated into parallel light beams. The lenses 132 can be concave lenses, convex lenses, etc. In a specific arrangement, the number and type of lenses in the collimating lens group 13 can be set in a manner commonly used at present, which will not be described here.

[0094] In addition, in a specific arrangement, the microlens array 12 can be fixed in the sleeve 131 of the collimating lens group 13 to achieve fixed connection between the microlens array 12 and the collimating lens group 13, thereby ensuring the positional accuracy and reliability between the microlens array 12 and the collimating lens group 13. In addition, after the microlens array 12 is fixed in the sleeve 131 of the collimating lens group 13, it is also beneficial to reduce the assembly difficulty of the entire laser emitting system 10, and to ensure the assembly accuracy and reduce the complexity between the laser 11, the microlens array 12 and the collimating lens group 13.

[0095] Alternatively, in some examples, the microlens array 12 can also be fixedly connected with the laser 11. The aperture (or area) of the microlens array 12 is substantially the same as the light exit surface 110 of the laser 11, so as to effectively combine the laser 11 and the microlens array 12. In addition, it is also helpful to improve the utilization rate of the aperture of the microlens array 12.

[0096] Of course, in some examples, the microlens array 12 can also be installed between the laser 11 and the collimating lens group 13 through an independent lens barrel. In a specific arrangement, the connection mode between the laser 11, the microlens array 12 and the collimating lens group 13 can be reasonably set according to actual needs, which will not be described here.

[0097] In actual application, the above-mentioned laser emitting system 10 can be applied in various scenarios relying on laser for ranging or detection.

[0098] For example, as shown in FIG. 19, the embodiment of the present application further provides a laser radar system 20, comprising the laser emitting system 10 and the laser receiving system 21. The laser emitting system 10 is used to project laser beams into the space, and the laser receiving system 21 is used to receive the laser beams reflected by the object 001 in the space. In the laser radar system 20 provided by the embodiment of the present application, the detection performance of the laser radar system 20 can be effectively improved by equipping the laser emitting system 10. For example, when some light emitting parts of the laser emitting system 10 fail, the laser beams generated by the laser emitting system 10 can still be projected into multiple regions in the space, so that the laser receiving system 21 can receive effective reflected laser beams, thereby having better detection capability. In addition, when the laser emitting system 10 performs partitioned light projection, because the crosstalk between different partitions is small enough, the reflected light received by the laser receiving system 20 also has obvious regionality, and has better detection performance. It can be understood that in actual application, the laser receiving system 21 can adopt the types and structural forms commonly used at present, and the type of the laser receiving system is not limited in the present application.

[0099] In various embodiments of the present application, the terms and / or descriptions of different embodiments are consistent and can be mutually referred to if there is no special description and logical conflict. The technical features in different embodiments can be combined to form new embodiments according to their inherent logical relationship.

[0100] In the present application, "multiple" refers to two or more. "And / or" describes the association relationship of the associated objects, which means that there can be three kinds of relationships, for example, A and / or B, which can represent the following three cases: A exists alone, A and B exist together, and B exists alone, where A and B can be singular or plural.

[0101] It can be understood that the various numbers involved in the embodiments of the present application are only for convenient differentiation, and do not limit the scope of the embodiments of the present application. The size of the serial number of the above processes does not mean the order of execution, and the execution order of the processes should be determined according to its function and inherent logic.

Claims

1. A laser emitting system, characterized in that, Includes lasers and microlens arrays; The laser has a plurality of light-emitting sections arranged at intervals along a first direction; The microlens array is used to receive the incident light from the laser and to deflect the incident light before transmitting the outgoing light. Wherein, along the first direction, the plurality of light-emitting parts include the Mth light-emitting part and the Nth light-emitting part; The projection area of ​​the Mth light-emitting part in space covers the projection area of ​​the Nth light-emitting part in space; Where M and N are both positive integers, and the difference between M and N is less than 5.

2. The laser emitting system according to claim 1, characterized in that, The backward extension of the incident light from the Mth light-emitting section, after being processed by the microlens array, passes through the Nth light-emitting section.

3. The laser emitting system according to claim 1 or 2, characterized in that, The laser includes multiple light sources; Along the first direction, the laser includes multiple light-emitting regions, and each light-emitting region includes multiple light-emitting parts; The number of light sources is the same as the number of light-emitting areas and corresponds one-to-one. The laser emitted by each light source is emitted through the light-emitting part in the corresponding light-emitting area.

4. The laser emitting system according to any one of claims 1 to 3, characterized in that, Along the first direction, the microlens array includes multiple lens units; Along the first direction, the distance between two adjacent light-emitting parts is D1, and the aperture of the light-emitting part is L1; The distance between two adjacent lens units is D2, and the aperture of the lens unit is L2; Where D2 = L2, and D2 is greater than 2(D1 + L1).

5. The laser emitting system according to any one of claims 1 to 3, characterized in that, Along the first direction, the microlens array includes multiple lens units, each of which has a focal length of F; The distance between the laser and the microlens array is Ld, where Ld is greater than 2F.

6. The laser emitting system according to any one of claims 1 to 5, characterized in that, The laser also includes a plurality of light-emitting sections arranged at intervals along a second direction, the second direction being perpendicular to the first direction; In particular, along the second direction, the backward extension line of the emitted light generated by the microlens array after the incident light from any of the light-emitting parts passes through the light-emitting part.

7. The laser emitting system according to any one of claims 1 to 6, characterized in that, The microlens array includes a first surface and a second surface that are opposite to each other. The first surface is a plane, and the second surface includes a plurality of lens units arranged along a first direction, and each lens unit is a convex lens.

8. The laser emitting system according to any one of claims 1 to 7, characterized in that, The microlens array is fixedly connected to the laser.

9. The laser emitting system according to any one of claims 1 to 8, characterized in that, The laser emission system also includes a collimating lens group; The collimating lens group is located on the light-emitting side of the microlens array, and the plurality of light-emitting parts are all located on the optical focal plane of the collimating lens group. The collimating lens group is used to collimate the outgoing light transmitted from the microlens array.

10. The laser emitting system according to claim 9, characterized in that, The collimating lens assembly includes a lens barrel and at least one lens fixed inside the lens barrel; The microlens array is fixed inside the lens barrel.

11. A lidar system, characterized in that, The system includes a laser receiving system and a laser emitting system as described in any one of claims 1 to 10, wherein the laser emitting system is used to project a laser beam into space, and the laser receiving system is used to receive a laser beam reflected from an object in space.

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