Laser transceiver system of laser radar

Abstract

The utility model discloses a laser transmit-receive system of a laser radar, comprising a rotating mirror rotating around a rotating shaft; the emission unit emits an emission light beam and emits the emission light beam to the environment through the first mirror surface of the rotating mirror; the receiving unit is used for receiving an echo light beam through the second mirror surface of the rotating mirror; wherein the transmitting unit comprises a plurality of line light sources and a transmitting lens, and the plurality of line light sources form a first matrix; the receiving unit comprises a plurality of photoelectric detection arrays and a receiving lens, the plurality of photoelectric detection arrays form a second matrix, and the photoelectric detection arrays located in adjacent columns are arranged in a staggered mode in the first direction. The first mirror surface and the second mirror surface are two adjacent mirror surfaces of the rotating mirror. According to the utility model, aberration can be improved, a receiving field angle corresponding to the photoelectric detector is reduced, the resolution of the laser radar is improved, and the resolution of the central field of view of the laser radar is doubled.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of laser radar based on photoelectric detection, especially relates to a laser radar laser transceiver system. BACKGROUND

[0002] Laser radar has been widely used in various fields due to its high precision, high resolution and other measurement advantages. In particular, in the field of autonomous vehicles, whether it is calibration, testing or actual scene application, laser radar as a core sensor is essential.

[0003] The laser transceiver system is an important part of the laser radar, and its design scheme directly determines the optical performance of the laser signal, thereby affecting the ranging capability and point cloud quality of the laser radar. However, in the prior art, there are problems such as large aberration of the transceiver system and low laser detection resolution, which limit the performance development and application range of the laser radar.

[0004] Therefore, the technical personnel in the art urgently need to solve the problem of improving aberration, reducing the receiving field angle corresponding to the photoelectric detector, and improving the resolution of the laser radar. UTILITY MODEL CONTENT

[0005] The technical problem solved by the utility model is to provide a laser radar laser transceiver system that improves aberration, reduces the receiving field angle corresponding to the photoelectric detector, and improves the resolution of the laser radar.

[0006] Furthermore, the resolution of the central field of view of the laser radar is doubled by using the arrangement of the photoelectric detection array.

[0007] The utility model discloses a laser radar laser transceiver system, which comprises:

[0008] The rotating mirror rotates around the rotation axis.

[0009] The transmitting unit emits a transmitting beam and emits it to the environment via the first mirror surface of the rotating mirror.

[0010] The receiving unit receives the echo beam via the second mirror surface of the rotating mirror.

[0011] The transmitting unit comprises a plurality of line light sources and a transmitting lens, and the plurality of line light sources form a first matrix.

[0012] The receiving unit comprises a plurality of photoelectric detection arrays and a receiving lens, and the plurality of photoelectric detection arrays form a second matrix, and the photoelectric detection arrays in adjacent columns are arranged staggered in the first direction.

[0013] The first mirror surface and the second mirror surface are two adjacent mirror surfaces of the rotating mirror.

[0014] The emission unit comprises a plurality of emission lenses, at least one emission lens corresponding to a plurality of laser sources, the centers of the plurality of emission lenses being arranged in sequence along a reference straight line, and the center column of the first matrix corresponding to the position of the reference straight line.

[0015] The linear light source is a VCSEL laser emitter.

[0016] The linear light source is a linear array detector or the linear light source is arranged in a row by a plurality of laser emitters.

[0017] The rotating mirror has at least three mirror surfaces, and each mirror surface has an angle with the rotating shaft which is not completely same.

[0018] The arrangement mode of the first matrix corresponds to the second matrix.

[0019] The photoelectric detection array is a one-dimensional array composed of a plurality of photoelectric detectors.

[0020] The photoelectric detection arrays in adjacent columns are staggered by an odd multiple of half of the receiving surface height of the photoelectric detector in the first direction.

[0021] Any field of view corresponding to the center field of view of the second matrix corresponds to at least two photoelectric detectors.

[0022] Through the above technical solution, the present application can improve aberration, reduce the receiving field angle of the photoelectric detector, and improve the resolution of the laser radar. Furthermore, the arrangement of the photoelectric detection array can double the resolution of the center field of view of the laser radar. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 Fig. 1 is a structural schematic diagram of a laser radar according to the present application.

[0024] Figure 2 Fig. 2 is a schematic diagram of a first matrix formed by a plurality of linear light sources according to the present application.

[0025] Figure 3 Fig. 3 is a corresponding relationship diagram between an emission lens and a linear light source according to the present application.

[0026] Figure 4 Fig. 4 is a first embodiment schematic diagram of a second matrix formed by a plurality of photoelectric detection arrays according to the present application.

[0027] Figure 5 Fig. 5 is a second embodiment schematic diagram of a second matrix formed by a plurality of photoelectric detection arrays according to the present application. DETAILED DESCRIPTION

[0028] The implementation process of the technical solution of the present application will be described below in combination with specific embodiments, which is not a limitation on the present application.

[0029] In order to improve the aberration of the laser radar, reduce the corresponding receiving field angle of the photoelectric detector, and improve the resolution of the laser radar, the utility model provides a laser radar laser transceiver system.

[0030] As Figure 1 It is the structure schematic drawing of the laser radar laser transceiver system of the utility model, and the schematic drawing is the overhead direction. The laser transceiver system includes the transmitting unit 1, the receiving unit 2 and the rotating mirror 3.

[0031] The rotating mirror 3 rotates around the rotation axis O. The rotating mirror has at least three mirror surfaces, preferably four mirror surfaces, and the included angle of each mirror surface with the rotation axis O is not completely the same, that is, the pitch of each mirror surface relative to the rotation axis O is different, and the projection direction of each mirror surface to the transmitting light beam is different.

[0032] The transmitting unit 1 is used to emit the transmitting light beam, and the transmitting light beam is emitted to the environment via the first mirror surface 31 of the rotating mirror 3. The receiving unit 2 is used to receive the echo light beam corresponding to the transmitting light beam, in particular, the echo light beam is received via the second mirror surface 32 of the rotating mirror.

[0033] The first mirror surface and the second mirror surface are two adjacent mirror surfaces of the rotating mirror.

[0034] The transmitting unit includes a plurality of line light sources 11 and a transmitting lens 12, and the plurality of line light sources form a first matrix.

[0035] The receiving unit includes a plurality of photoelectric detection arrays 21 and a receiving lens 22, and the plurality of photoelectric detection arrays form a second matrix.

[0036] Since the transmitting unit and the receiving unit both use their own lenses to realize the transmission and reception, the transmitting light path and the receiving light path are independent of each other, and the appropriate optical lens can be designed for each, thereby reducing the loss and distortion of the light beam in the propagation, helping to improve the imaging clarity and accuracy, having good imaging quality, and reducing the aberration.

[0037] The arrangement mode of the first matrix corresponds to the second matrix, so that the transmitting light path and the receiving light path can correspond to each other, and the receiving field and the transmitting field are nested with each other, so as to improve the optical efficiency of the overall system.

[0038] The linear light source adopts a VCSEL (Vertical-Cavity Surface-Emitting Laser) laser emitter, and specifically, the linear light source can be formed by closely arranging multiple laser emitters in a row.

[0039] As shown in Figure 2 is a schematic view of a first matrix formed by multiple linear light sources of the utility model, the view angle of the schematic view is Figure 1 from the direction of the receiving lens 22 to the emitting lens 12.

[0040] The first matrix includes multiple linear light sources, in the embodiment, the linear light sources are 8, which are not limited, and are arranged in 3 columns, the linear light sources A1, A2 and A3 are located in the first column, the linear light sources B1, B2 and B3 are located in the second column, and the linear light sources C1 and C2 are located in the third column. Figure 2 In the embodiment, the direction in which the dashed line extends downward is the first direction. The first direction is parallel to the rotation axis O.

[0041] The first linear light source of the first, second and third columns is staggered in the first direction in sequence, the linear light sources A1, B1 and C1 form a stepped arrangement, and a spacing is arranged between the adjacent linear light sources in each column.

[0042] In order to improve the efficiency of beam shaping of the emitted light beams, the laser transceiver system is provided with multiple emitting lenses, and each emitting lens corresponds to multiple linear light sources.

[0043] As shown in Figure 3 is a corresponding relationship diagram of the emitting lens and the linear light source of the utility model.

[0044] The emitted light beams emitted by the linear light sources A1, A2 and B1 are optically shaped by the emitting lens 121, the emitted light beams emitted by the linear light sources B2, C1 and C2 are optically shaped by the emitting lens 122, and the emitted light beams emitted by the linear light sources A3 and B3 are optically shaped by the emitting lens 123. The centers of the three emitting lenses are arranged in sequence along a reference straight line. In this way, the linear light sources in the first matrix can be uniformly arranged on both sides of the optical axis of the emitting lens, the light rays are more uniformly distributed, the field of view coverage effect is more sufficient, and the void is avoided.

[0045] The number of linear light sources corresponding to different emitting lenses can be the same or different. At least one emitting lens corresponds to multiple linear light sources, in the embodiment, each emitting lens corresponds to multiple linear light sources, and one emitting lens can also correspond to one linear light source.

[0046] The central columns (B1, B2, B3) of the first matrix correspond to the reference lines of the plurality of emitting lenses.

[0047] Multiple emitting lenses are used to group and shape different line sources in the first matrix. Line sources in adjacent positions are grouped into the same group, and line sources in the same group correspond to the same emitting lens, which means they are shaped with the same optical parameters, making their projection elevation directions roughly the same. Line sources in different groups correspond to different emitting lenses, resulting in shaping with different optical parameters, so that the projection directions of the three groups are different.

[0048] The differences in the initial positions and projection directions between different groups of line light sources result in variations in the projection between different groups, thereby increasing the coverage of the emission field of view in the first direction.

[0049] The photodetector array 21 can employ photodetectors such as APD, SiPM, SPAD, etc. This photodetector array is a one-dimensional array composed of multiple photodetectors.

[0050] Figure 4 The diagram shown is a schematic representation of the second matrix formed by multiple photoelectric detection arrays of this invention. Figure 4 As shown, each of the photoelectric detection arrays includes four photodetectors, which are arranged in close succession to form a one-dimensional array.

[0051] and Figure 2 Corresponding to the first matrix shown, this utility model has 8 photoelectric detection arrays forming a 3-column matrix. The first photoelectric detection arrays of the first, second, and third columns are staggered in the first direction to form a stepped arrangement, and there is a spacing between adjacent photoelectric detection arrays in each column.

[0052] Each photodetector has a receiving surface with a surface height H, and the corresponding photodetector arrays in adjacent columns are offset by an odd multiple of H / 2 in the first direction, such that the resolution in the central field of view is twice the resolution in the edge field of view.

[0053] like Figure 4 As shown, the first column has photoelectric detection arrays D1, D2, and D3, the second column has photoelectric detection arrays E1, E2, and E3, and the third column has photoelectric detection arrays F1 and F2.

[0054] The photoelectric detection arrays D1, E1 are staggered by 2.5H in the first direction, the photoelectric detection arrays E1, F1 are staggered by 1.5H in the first direction, the photoelectric detection arrays D2, F1 are staggered by 2.5H in the first direction, the photoelectric detection arrays D2, E2 are staggered by 1.5H in the first direction, the photoelectric detection arrays E2, F2 are staggered by 2.5H in the first direction, the photoelectric detection arrays F2, D3 are staggered by 1.5H in the first direction, and the photoelectric detection arrays D3, E3 are staggered by 2.5H in the first direction.

[0055] The receiving field of view positions of each photoelectric detection array are as shown in Figure 4 , and in particular, the receiving field of view positions of each photoelectric detector are as shown by the dashed lines in the figure. Due to the staggered arrangement of the photoelectric detection arrays relative to each other, the dashed line density of the middle section field of view LL' in the receiving field of view MM' is twice that of the sections ML or L'M'. It can be seen that by staggered arrangement of the photoelectric detection arrays in relay, the resolution of the central field of view of the laser radar is twice that of the edge field of view, and the detection capability and identification quality of the central field of view are improved.

[0056] In particular, in the field of view in the first direction, only two photoelectric detection arrays are arranged in the receiving section of the central field of view, for example, the section LN1 is provided only with the photoelectric detection arrays D1, E1, the section N1N2 is provided only with the photoelectric detection arrays E1, F1, the section N2N3 is provided only with the photoelectric detection arrays D2, F1, the section N3N4 is provided only with the photoelectric detection arrays D2, E2, the section N4N5 is provided only with the photoelectric detection arrays E2, F2, the section N5N6 is provided only with the photoelectric detection arrays D3, F2, and the section N6L' is provided only with the photoelectric detection arrays D3, E3. It can be seen that any field of view corresponding to the central field of view of the second matrix corresponds to at least two photoelectric detectors, and by having two photoelectric detectors corresponding to the same field of view in a smaller area, the receiving field of view angle corresponding to a single photoelectric detector can be reduced.

[0057] As shown in Figure 4 , the angles between each mirror surface of the rotating mirror and the rotation axis are not the same, and the utility model can realize a scanning effect of 32x4=128 lines.

[0058] The staggered degree of the second matrix relative to each other is not limited to Figure 4 , for example, it can also be as shown in Figure 5The photoelectric detection arrays D1, E1 are staggered by 1.5H in the first direction, the photoelectric detection arrays E1, F1 are staggered by 2.5H in the first direction, the photoelectric detection arrays D2, F1 are staggered by 1.5H in the first direction, the photoelectric detection arrays D2, E2 are staggered by 2.5H in the first direction, the photoelectric detection arrays E2, F2 are staggered by 1.5H in the first direction, the photoelectric detection arrays F2, D3 are staggered by 2.5H in the first direction, and the photoelectric detection arrays D3, E3 are staggered by 1.5H in the first direction.

[0059] All of the photoelectric detection arrays of the second matrix correspond to the same receiving lens, and the central column of the second array is located on the optical axis of the receiving lens.

[0060] By the technical scheme, the aberration can be improved, the receiving field angle corresponding to the photoelectric detector can be reduced, and the resolution of the laser radar can be improved.

[0061] The above embodiments are only used for describing the technical scheme of the utility model, and should not be regarded as limiting the utility model.

Claims

1. A laser transceiver system for a lidar system, characterized in that, include: The rotating mirror rotates around its axis of rotation. The emitting unit emits a beam of light, which is then projected into the environment through the first mirror of the rotating mirror. The receiving unit receives the echo beam via the second mirror of the rotating mirror; The emitting unit includes multiple line light sources and emitting lenses, and the multiple line light sources form a first matrix; The receiving unit includes multiple photodetector arrays and a receiving lens. The multiple photodetector arrays form a second matrix, and the photodetector arrays located in adjacent columns are staggered in a first direction.

2. The laser transceiver system for a lidar as described in claim 1, characterized in that, The first mirror and the second mirror are two adjacent mirrors of the rotating mirror.

3. The laser transceiver system for a lidar as described in claim 1, characterized in that, The emitting unit includes multiple emitting lenses, at least one of which corresponds to multiple laser sources. The centers of the multiple emitting lenses are arranged sequentially along a reference straight line, and the center column of the first matrix corresponds to the position of the reference straight line.

4. The laser transceiver system for a lidar as described in claim 1, characterized in that, The line light source is a VCSEL laser emitter.

5. The laser transceiver system for a lidar as described in claim 1, characterized in that, The line light source is either a linear array detector or consists of multiple laser emitters arranged in a row.

6. The laser transceiver system for a lidar as described in claim 1, characterized in that, The rotating mirror has at least three mirror surfaces, each with an angle that is not exactly the same as the axis of rotation.

7. The laser transceiver system for a lidar as described in claim 1, characterized in that, The arrangement of the first matrix corresponds to that of the second matrix.

8. The laser transceiver system for a lidar as described in claim 1, characterized in that, This photoelectric detection array is a one-dimensional array composed of multiple photoelectric detectors.

9. The laser transceiver system for a lidar as described in claim 8, characterized in that, The photodetector arrays located in adjacent columns are offset in the first direction by an odd multiple of half the height of the receiving surface of the photodetector.

10. The laser transceiver system for a lidar as described in claim 9, characterized in that, Each field of view corresponding to the central field of view of the second matrix corresponds to at least two photodetectors.

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