阅读说明：本技术 激光雷达光学系统及激光雷达 (Laser radar optical system and laser radar ) 是由 程刚 刘娟娟 于 2020-05-18 设计创作，主要内容包括：本发明公开了一种激光雷达光学系统及激光雷达,涉及测量仪器技术领域。所述激光雷达光学系统包括发射系统和接收系统,其中,所述发射系统沿光线传输方向依次包括激光光源、矫正镜组以及准直镜组,所述激光光源用于发射多个光束,所述矫正镜组包括至少一个矫正透镜,所述矫正透镜用于矫正所述激光光源发出的多个光束,以使每一所述光束的中心轴对准所述准直镜组的入瞳中心。本发明旨在提供一种简单且效果好的激光雷达光学系统来提高激光雷达垂直空间分辨率。(The invention discloses a laser radar optical system and a laser radar, and relates to the technical field of measuring instruments. The laser radar optical system comprises an emitting system and a receiving system, wherein the emitting system sequentially comprises a laser light source, a correcting mirror group and a collimating mirror group along the light transmission direction, the laser light source is used for emitting a plurality of light beams, the correcting mirror group comprises at least one correcting lens, and the correcting lens is used for correcting the light beams emitted by the laser light source so as to enable the central axis of each light beam to be aligned with the entrance pupil center of the collimating mirror group. The invention aims to provide a simple and effective laser radar optical system to improve the vertical spatial resolution of a laser radar.)

1. The utility model provides a laser radar optical system, its characterized in that laser radar optical system includes transmitting system and receiving system, wherein, transmitting system includes laser source, correction mirror group and collimation mirror group in proper order along light transmission direction, laser source is used for launching a plurality of light beams, correction mirror group includes at least one correction lens, correction lens are used for correcting a plurality of light beams that laser source sent, so that each the center pin of light beam aligns the pupil center of entering of collimation mirror group.

2. The lidar optical system of claim 1, wherein the set of corrective lenses comprises one of the corrective lenses; and/or the presence of a gas in the gas,

the correcting lens has positive focal power, and the correcting lens has a first surface facing the laser light source and a second surface far away from the laser light source, wherein the first surface is a plane, and the second surface is a convex surface.

3. The lidar optical system of claim 1, wherein the corrective lens is a edged lens.

4. The lidar optical system of claim 1, wherein the laser light source comprises at least one laser emitter plate, each of the laser emitter plates comprises a plurality of lasers, the plurality of lasers are spaced apart along a height direction of the laser emitter plate, central axes of light beams emitted by the lasers are parallel to each other, and the central axes are parallel to an optical axis of the correcting lens group.

5. The lidar optics system of claim 4, wherein the laser transmitter plate further comprises at least one shaping microlens disposed on an exit side of the plurality of lasers for fast axis divergence compression of the lasers.

6. The lidar optical system of claim 4, wherein a spacing between the corrective lens and the shaping microlens is D, 0.5mm ≦ D ≦ 5 mm; and/or the presence of a gas in the gas,

the shaping micro lens is a bare optical fiber, and the central axis of the bare optical fiber is perpendicular to the light beam emitted by the laser.

7. The lidar optical system of claim 6, wherein the surface of the bare fiber is coated with an antireflection film corresponding to a wavelength band of a light beam emitted from the laser.

8. The lidar optical system of claim 1, wherein the receiving system comprises a receiving lens group and at least one laser receiving plate in this order in a light transmission direction;

the laser radar optical system further comprises an emission reflector group and a receiving reflector group, the emission reflector group is arranged between the correcting mirror group and the collimating mirror group, and the receiving reflector group is arranged between the receiving lens group and the laser receiving plate.

9. The lidar optical system of claim 1, wherein the set of transmit mirrors comprises at least one transmit mirror; and/or the presence of a gas in the gas,

the set of receiving mirrors comprises at least one receiving mirror.

10. Lidar characterized in that it comprises a lidar optical system according to any of claims 1 to 9.

Technical Field

The invention relates to the technical field of measuring instruments, in particular to a laser radar optical system and a laser radar.

Background

At present, the mechanical laser radar is one of the most effective implementation modes for meeting the automatic driving stability, multi-path signal detection is realized by adopting a plurality of lasers and photoelectric detectors, and the plurality of lasers are vertically arranged at different height positions of a focal plane of a transmitting lens according to a preset pointing angle to realize a preset vertical field angle.

In order to improve the vertical spatial resolution of the laser radar, a plurality of methods are adopted at present: (1) the laser arrangement interval on a single transmitting plate is reduced, however, when a plurality of lasers are integrated on one transmitting plate, preset directional included angles need to exist among the lasers, so that interference is easily generated in the manufacturing process, the processing difficulty is increased, the lower limit of the laser arrangement interval is limited, and the vertical spatial resolution of the laser radar is further limited; (2) the plurality of transmitting plates are arranged in parallel and staggered in height, and the laser interval is reduced through the high dislocation of the laser, so that the difficulty of installation and debugging in the given space is high, and the system space is difficult to compress. With current technology, it is difficult to have a simplified way to improve the lidar vertical spatial resolution.

Disclosure of Invention

The invention mainly aims to provide a laser radar optical system and a laser radar, and aims to provide a simple and effective laser radar optical system to improve the vertical spatial resolution of the laser radar.

In order to achieve the above object, the present invention provides a lidar optical system, which includes an emitting system and a receiving system, wherein the emitting system sequentially includes a laser light source, a correcting lens group and a collimating lens group along a light transmission direction, the laser light source is configured to emit a plurality of light beams, the correcting lens group includes at least one correcting lens, and the correcting lens is configured to correct the plurality of light beams emitted by the laser light source, so that a central axis of each light beam is aligned with a center of an entrance pupil of the collimating lens group.

Optionally, the group of corrective lenses comprises one of the corrective lenses; and/or the presence of a gas in the gas,

the correcting lens has positive focal power, and the correcting lens has a first surface facing the laser light source and a second surface far away from the laser light source, wherein the first surface is a plane, and the second surface is a convex surface.

Optionally, the corrective lens is a edged lens.

Optionally, the laser light source includes at least one laser emitting panel, each laser emitting panel includes a plurality of lasers, the plurality of lasers are arranged at intervals along a height direction of the laser emitting panel, central axes of light beams emitted by the lasers are parallel to each other, and the central axes are parallel to an optical axis of the correcting lens group.

Optionally, the laser emission panel further includes at least one shaping microlens, and the shaping microlens is disposed on the light exit side of the plurality of lasers, and is used for performing fast axis divergence angle compression on the lasers.

Optionally, the distance between the correcting lens and the shaping micro lens is D, and D is more than or equal to 0.5mm and less than or equal to 5 mm; and/or the presence of a gas in the gas,

the shaping micro lens is a bare optical fiber, and the central axis of the bare optical fiber is perpendicular to the light beam emitted by the laser.

Optionally, an antireflection film is plated on the surface of the bare fiber, and the antireflection film corresponds to a wavelength band of a light beam emitted by the laser.

Optionally, the receiving system comprises a receiving lens group and at least one laser receiving plate in sequence along the light transmission direction;

the laser radar optical system further comprises an emission reflector group and a receiving reflector group, the emission reflector group is arranged between the correcting mirror group and the collimating mirror group, and the receiving reflector group is arranged between the receiving lens group and the laser receiving plate.

Optionally, the set of emission mirrors comprises at least one emission mirror; and/or the presence of a gas in the gas,

the set of receiving mirrors comprises at least one receiving mirror.

In addition, the invention also provides a laser radar which comprises the laser radar optical system.

The laser radar optical system provided by the invention comprises a transmitting system and a receiving system, wherein the transmitting system sequentially comprises a laser light source, a correcting lens group and a collimating lens group along the light transmission direction, a plurality of light beams emitted by the laser light source are corrected by using the correcting lens group, so that each light beam enters the collimating lens group in a mode that a central shaft is aligned with the center of an entrance pupil of the collimating lens group, the light beams emitted by the laser light source do not need to preset a pointing included angle, the mutual interference among the light beams is avoided, the interval of lasers can be reduced to be smaller, the improvement of the vertical spatial resolution of the laser radar is facilitated, in addition, the optical system is simple in structure, small in manufacturing difficulty and beneficial to quantitative production.

Drawings

Fig. 1 is a schematic diagram of a first embodiment of a lidar optical system set forth in the present disclosure;

FIG. 2 is a schematic diagram of the transmitting system of FIG. 1;

FIG. 3 is a front view of the corrective lens of FIG. 1;

FIG. 4 is a top view of the corrective lens of FIG. 3;

FIG. 5 is a diagram illustrating an exemplary embodiment of a laser emitter plate of the lidar optical system according to the present disclosure;

FIG. 6 is a schematic diagram of another embodiment of a laser emitter plate of the lidar optical system of the present invention;

fig. 7 is a schematic diagram of a second embodiment of the lidar optical system of the present invention;

fig. 8 is a schematic diagram of a third embodiment of the lidar optical system of the present invention.

The implementation, functional features and advantages of the objects of the present invention will be further explained with reference to the accompanying drawings.

The reference numbers illustrate:

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It should be noted that, if directional indications (such as up, down, left, right, front, and back … …) are involved in the embodiment of the present invention, the directional indications are only used to explain the relative positional relationship between the components, the movement situation, and the like in a specific posture (as shown in the drawing), and if the specific posture is changed, the directional indications are changed accordingly.

In addition, if there is a description of "first", "second", etc. in an embodiment of the present invention, the description of "first", "second", etc. is for descriptive purposes only and is not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In addition, the meaning of "and/or" appearing throughout includes three juxtapositions, exemplified by "A and/or B" including either A or B or both A and B. In addition, technical solutions between various embodiments may be combined with each other, but must be realized by a person skilled in the art, and when the technical solutions are contradictory or cannot be realized, such a combination should not be considered to exist, and is not within the protection scope of the present invention.

The vertical spatial resolution of the laser radar is determined by the vertical interval of a laser at a transmitting end, and in order to improve the vertical spatial resolution of the laser radar, a plurality of modes are adopted at present, and the method mainly comprises the following steps: (1) the laser arrangement interval on a single transmitting plate is reduced, however, when a plurality of lasers are integrated on one transmitting plate, preset directional included angles need to exist among the lasers, so that interference is easily generated in the manufacturing process, the processing difficulty is increased, the lower limit of the laser arrangement interval is limited, and the vertical spatial resolution of the laser radar is further limited; (2) the plurality of transmitting plates are arranged in parallel and staggered in height, and the laser interval is reduced through the high dislocation of the laser, so that the difficulty of installation and debugging in the given space is high, and the system space is difficult to compress. With current technology, it is difficult to have a simplified way to improve the lidar vertical spatial resolution.

In view of this, the present invention provides a laser radar optical system 100, which includes an emitting system 10 and a receiving system 20, wherein the emitting system 10 sequentially includes a laser light source 1, a correcting lens group and a collimating lens group 3 along a light transmission direction. Fig. 1 to 4 illustrate an embodiment of a lidar optical system 100 according to the present invention.

Referring to fig. 1 and 2, lidar optical system 100 includes a transmitting system 10 and a receiving system 20. The emission system 10 includes a laser light source 1, a correcting lens group and a collimating lens group 3 sequentially arranged along the light transmission direction. The laser light source 1 is used to emit a plurality of light beams. The correcting lens group comprises at least one correcting lens 2, and the correcting lens 2 is used for correcting a plurality of light beams emitted by the laser light source 1, so that each light beam enters the collimating lens group 3 in a manner that the central axis of the light beam is aligned with the center of the entrance pupil of the collimating lens group 3. Lens 2 is corrected to this embodiment has carried out the predistortion to the light beam on the one hand, make the light beam that laser light source 1 sent no longer need predetermine directional contained angle, thereby the restriction to laser beam has been relaxed, each light beam is if launched with the mode that the center pin is parallel to each other, not only can avoid mutual interference between each light beam, make laser 110 interval can shrink littleer, and the processing degree of difficulty has been reduced, be favorable to improving laser radar's vertical space resolution, on the other hand, because the light beam after correcting by correcting the mirror group all with the entrance pupil center of center pin incident collimating mirror group 3, the energy of each light beam can be by make full use of, thereby need not increase the optical aperture of system, and then the cost that has reduced collimating mirror group 3 and occupied space. The collimating lens group 3 is composed of one or more optical lenses, and the lenses preferably adopt a gaussian structure form, and are used for effectively collimating the light beams corrected by the correcting lens group to form a plurality of parallel light beams with different view field angles, so that the vertical view field coverage of the laser radar is realized.

As shown in fig. 1, the receiving system 20 includes a receiving lens group 8 and a laser receiving plate 6, which are sequentially arranged along the light transmission direction, the receiving lens group 8 is composed of one or more optical lenses, and the lenses preferably adopt a gaussian structure form for converging the light beam reflected by the detected object on the laser receiving plate 6, and the material of the receiving lens group 8 may adopt optical plastics; the laser receiving plate 6 includes a plurality of photodetectors for processing the received light beams. Further, in order to reduce the adverse effect caused by the interfering light beams, the receiving system 20 may further include a filter 7, the filter 7 is disposed between the receiving lens group 8 and the laser receiving plate 6, and is used for filtering each received light beam to filter out light beams having wavelengths not within the preset wavelength range, so that the interfering light beams may be prevented from affecting the light beams within the wavelength range, and the filter 7 may be disposed on the light incident side of the laser receiving plate 6 to protect the laser receiving plate 6 from being sealed.

After being corrected by the correcting lens group, the light beam emitted by the laser light source 1 enters the collimating lens group 3 in a manner that the central axis is aligned with the center of the entrance pupil of the collimating lens group 3, the collimated light beam is reflected by a detection object in front, and at least part of the reflected light beam enters the receiving lens group 8 and then is converged on the laser receiving plate 6.

In a specific implementation, the transmitting system 10 and the receiving system 20 may be symmetrically arranged along the central axis 5 of the system as shown in fig. 1, and a light-shielding device is disposed between the two to achieve spatial separation, so as to avoid mutual interference. Moreover, the collimating lens group 3 and the receiving lens group 8 of the present embodiment can adopt the same components, which is beneficial to reducing the cost during batch production.

The correcting lens group comprises at least one correcting lens 2, and specifically, when the correcting lens group comprises a plurality of correcting lenses 2, the plurality of correcting lenses 2 are coaxially arranged. As a preferred embodiment of the present invention, as shown in fig. 1, the correcting lens group includes a correcting lens 2, so that it can be ensured that most of the light beams enter the collimating lens group 3 in a manner that the central axis of the light beam is aligned with the center of the entrance pupil of the collimating lens group 3, thereby reducing the production cost while ensuring the product quality.

Referring to fig. 3 and 4, the correcting lens 2 has a positive power, and the correcting lens 2 has a first surface 21 disposed toward the laser light source 1 and a second surface 22 disposed away from the laser light source 1, wherein the first surface 21 is a plane and the second surface 22 is a convex surface.

For installing the correction lens 2, the emission system 10 of the present embodiment may further include a support for installing the laser light source 1 and the correction lens group, and since the correction lens group is disposed on the light emitting side of the laser light source 1 and is disposed adjacent to the laser light source 1, the correction lens group may play an effective protection role for the laser light source 1, thereby avoiding damage to the laser light source 1 during installation and debugging, and avoiding deposition of impurities on the surface of the laser light source 1. Further, the support can also set up to both ends open-ended tubular structure, and laser source 1 installs in the first end of support, corrects the mirror group and installs the second end at the support, so, can enclose between support, laser source 1 and the correction mirror group and close and constitute an airtight space to prevent that impurity from getting into this airtight space, and then effectively increased device life-span and system life-span. Wherein, the correction lens 2 can be fixedly arranged on the bracket in a viscose mode.

The corrective lens 2 of the present embodiment is preferably a edged lens. On the basis of the conventional round lens, as shown in fig. 3, the symmetrically distributed areas a and B are cut off to form the edge-cut lens, which has a smaller volume and is suitable for assembly compared with the conventional round lens, not only is the required bracket easier to process, but also when the edge-cut lens is installed on the bracket, the assembly is more convenient and the occupied space is smaller, so that the optical system can be more compact. Further, as shown in fig. 3 and 4, the rectangular edge-cut lens is preferred in this embodiment, that is, the edge-cut lens obtained by cutting out the regions A, B, C and D on the basis of the conventional round lens, so as to further reduce the volume of the lens, and make the lens form four straight sides, further reducing the assembly difficulty.

The laser light source 1 of the present embodiment includes at least one laser emitting panel 11, and each laser emitting panel 11 is disposed on the same vertical plane. Each laser emitting panel 11 includes a plurality of lasers 110, the plurality of lasers 110 are arranged at intervals along the height direction of the laser emitting panel 11, the central axes of the light beams emitted by the lasers 110 are parallel to each other, and the central axes are parallel to the optical axis of the correcting lens group. Taking fig. 2 as an example, the laser light source 1 of the present embodiment includes a laser emitting plate 11, the laser emitting plate 11 includes nine lasers 110 arranged from top to bottom at intervals, central axes of light beams respectively emitted by the nine lasers 110 and an optical axis of the correction lens 2 are parallel to each other, that is, there is no interference included angle between the light beams respectively emitted by the nine lasers 110, which reduces difficulty in manufacturing the laser emitting plate 11.

In order to optimize the system performance, the laser emitting panel 11 of the present embodiment further includes at least one shaping microlens 120, where the shaping microlens 120 is disposed on the light emitting side of the plurality of lasers 110, and is used for performing fast-axis divergence angle compression on the lasers 110. Referring to fig. 5 and 6, the right side of the laser 110 is the light-emitting side of the laser 110, and the shaping microlens 120 is disposed on the light-emitting side of the laser 110, so that the light beam emitted from the laser 110 is shaped by the shaping microlens 120 and then emitted. Since the light beams emitted by the plurality of lasers 110 on the laser emitting panel 11 of the present embodiment are all emitted in a manner that the central axes are parallel to each other, at least a part of the light beams can be shaped simultaneously, that is, one or more shaping microlenses 120 can be disposed on the light emitting sides of the plurality of lasers 110, as shown in fig. 5, one shaping microlens 120 can be disposed on the light emitting side of each laser 110, or one shaping microlens 120 can be shared by every two or more adjacent lasers 110, or as shown in fig. 6, one shaping microlens 120 can be shared by all the lasers 110, thereby further simplifying the manufacturing process of the laser emitting panel 11.

When the bare fiber is disposed on the light-emitting side of the laser 110 in a manner that the central axis is perpendicular to the light beam emitted by the laser 110, the light beam emitted by the laser 110 can also achieve the effect of shaping the light beam after passing through the bare fiber, and the shaping microlens 120 of the present embodiment is preferably a bare fiber, and as shown in fig. 5 and 6, the central axis of the bare fiber is disposed perpendicular to the light beam emitted by the laser 110.

Further, the surface of the bare fiber of this embodiment is plated with an antireflection film corresponding to the wavelength band of the light beam emitted from the laser 110, so as to reduce the reflected light formed on the surface of the bare fiber and increase the light transmittance.

The light-emitting position of the shaping microlens 120 forms a light-emitting plane, the distance between the light-emitting plane and the first surface 21 of the correction lens 2 is D, in this embodiment, the value range of D is preferably: d is more than or equal to 0.5mm and less than or equal to 5mm, the correction effect of the correction lens 2 on the light beam can be ensured in the range, and the smaller D is, the higher the system compactness is.

In order to further improve the compactness of the optical system, the laser radar optical system 100 of the invention further comprises an emission reflector group and a receiving reflector group, wherein the emission reflector group is arranged between the correcting reflector group and the collimating reflector group 3 and is used for refracting light transmitted from the correcting reflector group to the collimating reflector group 3, the distance between the laser light source 1 and the collimating reflector group 3 is shortened by changing the light path so as to compact the emission system 10, and the shape of the emission system 10 is adjusted by changing the light path so as to adapt to different appearance structures; the receiving reflector group is arranged between the receiving lens group 8 and the laser receiving plate 6 and is used for refracting the light transmitted from the receiving lens group 8 to the laser receiving plate 6, so that the distance between the receiving lens group 8 and the laser receiving plate 6 is shortened by changing the light path to enable the receiving system 20 to be compact, or the shape of the transmitting system 10 is adjusted to adapt to different appearance structures.