CN216646804U

CN216646804U - Light emitting module, light detection module and laser radar

Info

Publication number: CN216646804U
Application number: CN202123435951.6U
Authority: CN
Inventors: 陈杰; 向少卿
Original assignee: Hesai Technology Co Ltd
Current assignee: Hesai Technology Co Ltd
Priority date: 2021-12-30
Filing date: 2021-12-30
Publication date: 2022-05-31
Anticipated expiration: 2031-12-30

Abstract

The embodiment of the utility model provides a light emitting module, a light detection module and a laser radar, wherein the light emitting module comprises: a first planar support plate; a plurality of light emitting line arrays constituting a light emitting array, disposed on the first planar support plate, each light emitting line array including a plurality of light emitting units; the light emitting direction of the light emitting units is perpendicular to the first plane support plate, and the light emitting unit parts in at least two light emitting line columns are mutually staggered to form non-uniform distribution in the vertical direction. By adopting the scheme, the non-uniform distribution of the multi-line laser radar wire harness can be realized in a simple mode, the requirements of low power consumption and miniaturization of the laser radar are met, and the realization cost is reduced.

Description

Light emitting module, light detection module and laser radar

Technical Field

The embodiment of the utility model relates to the technical field of optical perception, in particular to a light emitting module, a light detection module and a laser radar.

Background

Lidar is a sensor that uses laser light to achieve precise ranging. The laser radar emits laser, the laser can be reflected when encountering surrounding objects, and the accurate distance of the objects can be calculated by measuring the time difference required by laser receiving and transmitting. In addition, the accurate three-dimensional structure information of the target object can be obtained by analyzing the information such as the energy size of the echo pulse, the amplitude, the frequency, the phase and the like of the spectrum, and a three-dimensional environment model, namely point cloud, can be constructed by expanding the view field through scanning or multi-beam. The application of the laser radar is very wide, and comprises automatic driving, smart city/Vehicle and Everything (V2X), robots and the like.

In order to acquire three-dimensional information of a scanned area as much as possible, a multi-line laser radar is mostly adopted at present, and the multi-line laser radar adopts a plurality of light emitting units (such as lasers) and corresponding detectors which are arranged in the vertical direction, so that a wider vertical field of view area can be covered. The vertical field angle is an angle which can be observed in the vertical direction, and most of the wire harnesses of the multi-line laser radar on the market are uniformly distributed in a certain angle range at present.

In view of the fact that the main detection target of the vehicle-mounted lidar is a pedestrian, a vehicle, or the like on the road surface, in order to improve the utilization efficiency of laser light, there has been a proposal that the light beam of the lidar is non-uniformly distributed in the vertical direction. As shown in fig. 1A and 1B, the conventional solution is that the light emitting module 10 is disposed on the base 11, a plurality of supporting plates 12 are mounted on the base 11, a plurality of lasers 13 are disposed on the plurality of supporting plates 12, respectively, and further, each laser 13 needs to be directed toward the center of a lens group (not shown) capable of emitting light. By the plurality of support plates 12 being spaced apart from each other in the vertical direction/longitudinal direction (i.e., Y direction in the drawing) relatively differently, non-uniform distribution of the emitted light beam of the laser radar in the vertical direction is achieved.

However, the solution of implementing non-uniform distribution of the emitted light beam of the laser radar in the vertical direction by installing a plurality of supporting plates is bulky, and it is difficult to satisfy the trends of low power consumption and miniaturization of the laser radar. In addition, the scheme has complex installation and high installation and debugging complexity in the practical application process, so the realization cost is high.

The statements in this background section merely represent techniques known to the public and are not, of course, representative of the prior art.

SUMMERY OF THE UTILITY MODEL

In view of this, embodiments of the present invention provide a light emitting module, a light detection module, a laser radar and a ranging method thereof, which can implement non-uniform distribution of a multi-line laser radar beam in a simple manner, meet requirements of low power consumption and miniaturization of the laser radar, and reduce implementation cost.

First, in an aspect of an embodiment of the present invention, there is provided an optical transmission module including:

a first planar support plate;

a plurality of light emitting line arrays constituting a light emitting array, disposed on the first planar support plate, each light emitting line array including a plurality of light emitting units;

the light emitting direction of the light emitting units is perpendicular to the first plane support plate, and the light emitting unit parts in at least two light emitting line rows are mutually staggered to form non-uniform distribution in the perpendicular direction.

Optionally, the plurality of light emission lines are arranged such that a density of the light emission units near a middle area of the first planar support plate in a vertical direction is greater than a density of the light emission units near upper and lower sides.

Optionally, the arrangement density of the plurality of light emitting line rows in the vertical direction tends to decrease from the middle to the upper and lower sides uniformly or in a gradient manner.

Optionally, the light emitting array is an encrypted area of the light emitting unit within a range of vertical field angle ± 5 °.

Optionally, a plurality of light emitting line columns in the light emitting array are distributed in multiple columns, and the light emitting units in different light emitting line columns are located in different rows.

Optionally, the intervals between the light emitting units in the light emitting line array are the same or non-uniformly distributed.

Optionally, the light emitting module is used for a laser radar, is disposed at a focal plane position of an emitting end of the laser radar, and further includes a field lens adapted to converge light emitted by the light emitting unit so as to pull back the light emitted by the light emitting unit to an optical axis of the emitting end.

Optionally, the light emitting module further comprises a lens group adapted to deflect the light emitted by the light emitting unit, so that the light emitted by the lasers, which are all emitting light perpendicular to the first planar supporting plate, can cover the entire vertical field of view of the lidar.

Optionally, the pitch of the light emission array formed by the plurality of light emission line columns is greater than or equal to the pitch of a single light emission line column divided by the number of staggered columns.

Optionally, the overlapping ratio of the light spots of the adjacent light emitting units is slightly smaller than the center distance between the two adjacent light emitting units.

Optionally, the light emitting unit comprises at least one of: vertical cavity surface emitting lasers, photonic crystal surface emitting semiconductor lasers.

Optionally, the plurality of light emission line arrays disposed on the first planar support plate have the same specification or have different specifications.

Secondly, in another aspect of the embodiments of the present invention, there is provided an optical detection module, including:

a second planar support plate;

the plurality of optical detection lines form an optical detection array which is arranged on the second plane supporting plate, each optical detection line comprises a plurality of optical detection units, and the optical detection units in at least two optical detection lines are partially staggered with each other and are in non-uniform distribution in the vertical direction.

Optionally, the plurality of optical detection lines are arranged such that the density of the optical detection units near the middle region of the second planar support plate in the vertical direction is greater than the density of the optical detection units near the upper and lower sides.

Optionally, the optical detection module is used for a laser radar, is disposed at a focal plane of a receiving end of the laser radar, and further includes a diaphragm and an optical filter, wherein:

the diaphragm is suitable for blocking stray light;

and the optical filter is suitable for only allowing light corresponding to the wavelength of the detection light beam emitted by the transmitting end of the laser radar to pass through and then enter the light detection unit.

In another aspect of the present invention, there is also provided a laser radar including: light emission module and with the light detection module that light emission module corresponds the arrangement, wherein:

the light emitting module is arranged on the focal plane of the emitting end and comprises:

a first planar support plate;

a plurality of light emitting line arrays constituting a light emitting array, disposed on the first planar support plate, each light emitting line array including a plurality of light emitting units; the light emitting direction of the light emitting units is vertical to the first plane support plate, and the light emitting units in at least two light emitting line rows are partially staggered with each other to form non-uniform distribution in the vertical direction;

the optical detection module is arranged on a focal plane of the receiving end and comprises:

a second planar support plate;

In another aspect of the embodiments of the present invention, there is also provided a ranging method for a laser radar, including:

respectively controlling the light emitting array to emit light pulses and controlling the light detecting array to receive light reflected by an external obstacle; wherein: the light emitting array and the light detecting array are correspondingly arranged; the light emitting array comprises a plurality of light emitting line rows, each light emitting line row is arranged on a first plane, each light emitting line row comprises a plurality of light emitting units, the light emitting directions of the light emitting units are vertical to the first plane, and the light emitting units are non-uniformly distributed in the vertical direction; the optical detection array comprises a plurality of optical detection line arrays, each optical detection line array is arranged on the second plane, and each optical detection line array comprises a plurality of optical detection units;

and calculating the position information of the obstacle according to the detection data of the light detection array, and combining the detection data of the light detection array in the full view field range into one frame to be output as point cloud.

By adopting the light emitting module provided by the embodiment of the utility model, the light emitting array formed by the plurality of light emitting line arrays is arranged on the single first plane supporting plate, and the light emitting direction of the light emitting units is vertical to the first plane supporting plate, wherein the light emitting units in at least two light emitting line arrays are partially staggered in the vertical direction, so that the non-uniform distribution of light beams in the vertical direction is realized in a simple and compact manner, the integral energy density of the light emitting module can be improved, the light emitting efficiency can be improved by the mutual staggering of the light emitting units in at least two light emitting line arrays in the vertical direction, the remote measuring capability of the multi-line laser radar can be improved, the power consumption of the laser radar is reduced, and the requirement of miniaturization of the laser radar is met. In addition, the structure is simple and compact, the implementation is easy, and the installation and the adjustment are convenient, so the implementation cost can be reduced.

Further, due to the arrangement of the light emitting lines, the density of the light emitting units close to the middle area of the first plane supporting plate in the vertical direction is greater than the density of the light emitting units close to the upper side and the lower side, so that the detection light beams can be focused on a main area where targets usually appear in a view field, the light emitting efficiency can be further improved under the condition that detection requirements are met, and the overall power consumption of the laser radar can be reduced.

Further, the arrangement density of the plurality of light emitting line rows in the vertical direction tends to be reduced from the middle to the upper and lower sides, so that the light emitting efficiency can be further improved under the condition of ensuring the detection accuracy.

Furthermore, the distance between each light-emitting unit in the light-emitting line array is in the trend of uniform change or gradient change, so that the light-emitting efficiency can be further improved and the overall power consumption of the laser radar can be reduced under the condition of meeting the detection requirement.

Furthermore, the overlapping ratio of the light spots of the adjacent light emitting units is slightly smaller than the center distance between the two adjacent light emitting units, so that the system resolution corresponding to the region of interest reaches the limit, the energy density of the light emitting module is further improved, and the distance measuring capability of the laser radar can be correspondingly improved as much as possible.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below, it is obvious that the drawings in the following description are only embodiments of the present application, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.

Fig. 1A and 1B are schematic diagrams illustrating different viewing angles of a light emitting module in the prior art;

FIG. 2A is a schematic diagram illustrating a planar structure of an optical transmitter module according to an embodiment of the present invention;

FIG. 2B is a schematic diagram showing the distribution of the emitted light beams of the light emitting module shown in FIG. 2A in a vertical field of view;

FIGS. 3A and 3B are schematic diagrams of an optical path of an optical transmitter module at a transmitting end, respectively;

FIG. 4A is a schematic diagram of a planar structure of an optical transmitter module according to an embodiment of the present invention;

FIG. 4B is a schematic diagram showing a distribution of emission beams of the optical transmission module shown in FIG. 4A in a vertical field of view;

fig. 5A to 5D are schematic plan views sequentially showing some of the light emitting modules in the embodiment of the present invention;

FIG. 6 is a schematic diagram illustrating a specific application scenario of the light emitting module applied to a vehicle during driving;

fig. 7A to 7C are schematic plan views sequentially showing other light emitting modules in the embodiment of the present invention;

FIG. 8 shows a schematic of the spots of adjacent lasers being encrypted;

fig. 9 is a schematic view showing a structure of a light emitting unit in the embodiment of the present invention;

fig. 10 is a schematic diagram showing a structure of a light emission line array in the embodiment of the present invention;

fig. 11A and 11B are schematic plan views respectively showing two kinds of light emitting modules in the embodiment of the present invention;

FIG. 12 is a schematic diagram of a lidar constructed in accordance with an embodiment of the utility model;

FIG. 13 is a schematic diagram showing a structure of an optical detection line array according to an embodiment of the present invention;

FIGS. 14A and 14B are schematic diagrams respectively showing the plane structures of two light detection modules in the embodiment of the present invention;

15A and 15B show schematic views of alternative examples of the relationship of the fields of view of the light emitting module and the light detecting module in the embodiment of the utility model;

fig. 16 shows a schematic structural diagram of a light detection unit in an embodiment of the present invention.

FIG. 17A is a schematic diagram illustrating a horizontal scanning process and a generated point cloud during non-round emission;

FIG. 17B is a schematic diagram showing the correspondence between the passage and the point cloud when the horizontal scanning type mechanical radar emits light in a non-round inspection manner;

FIG. 18A is a schematic diagram showing the correspondence between the horizontal scanning process and the generated point cloud during the round-robin illumination;

FIG. 18B is a schematic diagram showing the correspondence between a channel and a point cloud when a horizontal scanning type mechanical radar wheel patrol emits light;

fig. 19 is a flowchart illustrating a ranging method of a lidar according to an embodiment of the present invention.

Detailed Description

For the multi-line laser radar, the transmitting end is provided with a plurality of lasers, the plurality of lasers are used as light emitting units to emit a plurality of light beams, the plurality of light beams are unevenly distributed in a vertical view field of the laser radar system, that is, intervals of all the light beams in the vertical direction are not completely consistent, and because the light receiving and the light emitting have corresponding relations, at least partially overlapped view fields exist (light emitted by the transmitting end falls on a certain area on a target, and reflected light energy of the area is just returned to a detector of the receiving end), so that the resolution ratios of all point clouds are not all the same, which is called as uneven distribution of the light beams (or called as the light beams or called as the point clouds). For a multi-line lidar, this line is the scanning beam, which is the number of channels through which laser light is transmitted and received, or the minimum number of addressable channels. Typical lasers and detectors are 1:1 configuration, the number of scanning beams is equal to the number of lasers or detectors and the number of transmitting channels or receiving channels. Also, there may be situations where multiple detectors share a laser, or vice versa, or even where there may be staggering, where the scan beam can be determined by resolving the number of smallest addressable, gated channels.

As described in the background section, in the current scheme capable of realizing non-uniform distribution of light beams, it is difficult to meet both the requirements of high measurement accuracy and low power consumption in practical application scenarios and the requirements of miniaturization. In addition, the complexity of assembly and debugging is high.

In view of the above problems, an aspect of the embodiments of the present invention provides, at a transmitting end, a light emitting module capable of realizing non-uniform distribution of a light beam. In detail, by disposing a light emitting array composed of a plurality of light emitting line arrays on a planar support plate (hereinafter referred to as a first planar support plate for convenience of description), a plurality of support frames are not required, and since the light emitting directions of the light emitting units are all the same and are all perpendicular to the plane of the first planar support plate, it is not necessary to deflect each light emitting unit on each support frame in different directions through complicated adjustment so as to achieve all light beam pointing centers, and the light emitting units in at least two light emitting line arrays are partially staggered with each other, thereby realizing non-uniform distribution of light beams in the vertical direction in a simple and compact manner.

In another aspect of the embodiments of the present invention, in a receiving end, there is provided an optical detection module with non-uniform distribution of optical detection units, and in a specific implementation, the receiving end and the transmitting end both have a corresponding relationship (at least partial fields of view of the receiving end and the transmitting end coincide with each other to achieve detection of an object in at least the coinciding fields of view), and also adopt a similar arrangement layout manner, thereby achieving non-complete uniformity, i.e., non-uniform distribution, of resolutions of all the wire bundles or the entire point cloud in a vertical direction.

In another aspect of the embodiments of the present invention, a laser radar may include the light emitting module in the embodiments of the present invention at a transmitting end, and may include the light detecting module in the embodiments of the present invention at a receiving end, and by using the light emitting module and the light detecting module for environment sensing, non-uniformly distributed point cloud data may be generated in a direction perpendicular to a field of view. Because the structure of receiving and dispatching end (transmitting terminal and receiving terminal) is succinct compact, consequently can improve the long-range ability of surveying and measurement accuracy of multi-thread lidar, satisfy the miniaturized demand of lidar, and because all the light emission unit all sets up on a plane backup pad (be first plane backup pad) among the light emission module, need not to let every light emission unit point heart again, but directly let the light emission unit paste in this planar backup pad can, consequently the dress of being convenient for extremely transfers.

In consideration of cost, whether the light emitting lines are staggered and the specific staggered area and degree can be designed according to practical situations. For example, the setting may be made based on an area where the object to be measured generally appears in the vertical field of view.

In a specific implementation, for the light emitting module, each light emitting unit can be directly attached to the first planar supporting plate through a mounting process, and similarly, for the light detecting module, each light detecting unit can also be directly attached to the second planar supporting plate through a mounting process.

For the laser radar provided by the embodiment of the utility model, because the transmitting end and the receiving end both adopt the design of the planar device, the structure is compact, and the transmitting end and the receiving end can use symmetrical light paths, the light-focusing efficiency is very high, and the first planar supporting plate of the transmitting end and the second planar supporting plate of the receiving end are both vertical to the optical axis, when the optical-mechanical structure slightly deforms due to temperature or stress, especially the warping of the first planar supporting plate or/and the second planar supporting plate does not cause serious light position change, namely the corresponding relation of the transceiving channels is basically stable. Therefore, as long as enough patch precision is ensured, the whole light focusing can be realized, and the installation and adjustment time is greatly saved.

In addition, the light emitting unit does not need to point to the center, but only a telecentric light path is matched with the light emitting unit, namely, a field lens is placed near a focal plane, and the light path is pulled back to the optical axis, so that the chip mounting efficiency of the light emitting unit can be improved. In conclusion, the overall implementation cost of the laser radar can be reduced.

For those skilled in the art to better understand the technical concept and principles of the embodiments of the present invention, and to understand the technical advantages and effects thereof, the following detailed description is given by way of specific application examples with reference to the accompanying drawings.

First, referring to a schematic plan structure of a light emitting module shown in fig. 2A, in an embodiment of the present invention, as shown in fig. 2A, the light emitting module a0 may include: a first planar support plate AB0, and a light emission array AX0 of a plurality of light emission line columns (e.g., AL1, AL2, and AL3), the light emission array AX0 being disposed on the first planar support plate AB 0. Wherein each light emission line array includes a plurality of light emission units AU disposed in a vertical direction, and a light emitting direction of each light emission unit AU is perpendicular to the first plane support plate AB0, wherein light emission units in at least two light emission line arrays partially cross each other (overlap) in the vertical direction to form an encryption area.

For example, specifically to the light emission array AX0 shown in fig. 2A, it includes light emission line columns AL1, AL2 located at the 0 th column and light emission line columns AL3 located at the 1 st column, in which light emission line columns AL1 and light emission line columns AL3 are staggered with each other in the VA0 region in the vertical direction. More specifically, as shown in fig. 2A, in the vertical direction, the light emission unit AU30 in the light emission line array AL3 is interleaved between the light emission unit AU12 and the light emission unit AU13 in the light emission line array AL1, and the light emission unit AU31 is interleaved between the light emission unit AU13 and the light emission unit AU 14. The light emitting unit AU may specifically be a laser. As an alternative example, the light emission unit AU may specifically be a vertical cavity emission unit.

With the above-described arrangement, it is only necessary to provide the light emission array AX0 formed by a plurality of light emission line arrays on the single first planar supporting plate AB0, and since the light emission direction of the light emission units AU is perpendicular to the first planar supporting plate AB0, the line beams formed by the light emission units AU in at least two light emission line arrays emitting light are staggered from each other in the perpendicular direction. For example, referring to fig. 2A in combination with fig. 2B, since the areas OL0 of the light emission line array AL1 and the light emission line array AL3 in the vertical direction are staggered with each other, and accordingly, the distribution of all the line beams/point clouds of the radar in the vertical field of view direction is not uniform, the resolution of the light beams in the vertical direction within the area OL0 is higher, and as shown in fig. 2B, the density of the emission light beams in the area of the vertical field of view V11 (corresponding to the area of VA0 in the vertical direction in fig. 2A) is greater than that in the areas of the field of view V12, V13.

In addition, due to the correspondence between the transmission and the reception, the resolution or the point cloud density in the vertical field of view V11 area (corresponding to VA0 in fig. 2A) can be higher than those in the field of view areas V12 and V13 for the radar complete machine.

In a specific implementation, the planar supporting Board AB0 may be a Printed Circuit Board (PCB), and the specific shape and configuration of the outline of the planar supporting Board AB0 are not limited in the embodiments of the present invention.

In a specific implementation, the light Emitting unit AU may be a Vertical Cavity Emitting Laser, such as a Vertical Cavity Surface Emitting Laser (VCSEL), a photonic Crystal Surface Emitting semiconductor Laser (PCSEL), or the like.

The VCSEL is easy to integrate two dimensions due to the fact that light beams of the VCSEL are emitted perpendicular to the substrate, wafer level manufacturing is achieved, and the VCSEL has the advantages of being low in power consumption, small in temperature drift coefficient, strong in robustness, low in cost and the like. The PCSEL emits laser from the top surface, so the PCSEL is easy to be packaged and integrated into a printed circuit board and an electronic component, and has the advantages of low cost, strong robustness, wide wavelength range, high power and the like.

In addition, in the specific implementation, since all the light emitting units (such as lasers) emit light perpendicular to the first planar supporting plate, in order to realize the detection of a certain vertical field range, the emitting end can adopt a telecentric optical path to complete the pointing center of the light emitting direction of the lasers, so as to improve the transmittance of each channel in the lens. The telecentric optical path is mainly characterized in that a light emitting array (e.g. a laser array) is arranged on a focal plane of the emitting optical path, and further within a certain distance range, such as 15mm, near the focal plane, a lens, also called a Field lens, is designed to pull back light emitted from a light emitting unit (e.g. a laser) to an optical axis of an emitting optical path, such as the optical path diagram of the emitting end shown in fig. 3, lasers La 01-La 03 are all arranged on a first plane support plate AB3a, although the emitted light is perpendicular to the direction of the support plate, and is emitted to the outside of the radar after being shaped and deflected by a Field lens FL0 and other lens groups La0, so that all the emitted light of the lasers of the laser radar covers the entire Field of View, FoV range of the laser radar in the vertical direction, and in addition, for the receiving end, a detection module correspondingly provided with planarization is arranged on the focal plane of the receiving end, the laser beam emitted by the emitting end meets external obstacles and is reflected, at least part of the light returns to the detection module, passes through the diaphragm, is blocked by some stray light outside the preset FoV, passes through the optical filter, and is only allowed to reach the wavelength f of the detection beam emitted by the emitting end of the laser radar₀Corresponding light (within a certain pulse width, f)₀± Δ f) detection over a vertical field of view can be achieved by incidence on the light detection unit. Then combined with a rotary scanning accessory such as a rotary mirror or a galvanometer mirror or a Micro-Electromechanical System (MEMS) or a traditional mechanical radar or an optical phased arrayThe Optical Phase Array (OPA) or the liquid crystal, etc., can realize the scanning and detection of the obstacles in a certain horizontal field range and a certain vertical field range by expanding the horizontal scanning field.

Further, in order to improve the transmittance of light emitted from the light emitting unit in the lens group, as shown in fig. 3B, a microlens array mLX may be further added on the light exit side of each laser (e.g., Lb01 to Lb03) to further compress the divergence angle.

It should be noted that, the above is only an exemplary illustration, and the embodiment of the present invention does not limit the specific type of the adopted light emitting unit, and the light emitting direction can be perpendicular to the first plane support plate.

In a specific implementation, considering the practical application scenario of the optical transmission module, for example, the optical transmission module may be applied to a laser radar, and if the laser radar is used as a sensing device of an automatic driving device, an Advanced Driver Assistance System (ADAS) or a robot, and mainly detects a target such as a pedestrian on the ground, a moving vehicle, and the like, the light beam emitted into a high sky, for example, is largely wasted outside the area where the target may appear. For this purpose, the arrangement of the plurality of light emission lines may be set in a targeted manner such that the density of the light emission units in the vertical direction near the middle region of the first planar support plate is greater than the density of the light emission units near the upper and lower sides.

For example, with continued reference to fig. 2A and 2B, in which the density of the light emitting units in the OL0 area is greater than the density of the light emitting units in the upper and lower side areas thereof, accordingly, the density of the line beam or point cloud of the radar in the vertical field of view V11 area is greater than the density in the field of view areas V12, V13 area.

Referring next to the schematic plan view of the light emitting module shown in fig. 4A and the schematic diagram of the distribution of the emitted light beams in the vertical field of view shown in fig. 4B, the light emitting module a1 is different from the light emitting module a0 in that, in the light emitting array AX1, the light emitting module AL1 in the 0 th column is closer to the light emitting module AL2, the structure is more compact, and the light-emission line column AL3 located at column 1 is more centrally located, for example, may be horizontally symmetrical along a center line between the light-emission line columns AL1 and AL2, so that the light-emission line column AL3 is vertically staggered from both the light-emission line columns AL1 and AL2, and thus, the density of the beam or the point cloud of the radar in the vertical field of view V21 area is greater than that in the field of view areas V22 and V23 area, and the coverage of the beam in the field of view areas V22 and V23 area is approximately equal. In addition, a plurality of light emission lines in the light emission array are distributed in a plurality of columns, and the light emission units in different light emission lines are positioned in different rows. Referring to fig. 4A, the light emitting line columns AL1, AL2 and AL3 constitute a light emitting array, which is distributed in 2 columns in total, i.e. along the Y direction on the figure, and the light emitting units AU in the light emitting line columns AL1 and AL3 are distributed on different rows, i.e. in the X direction dimension, at different positions.

As also shown in fig. 5A, the light emitting module a2 includes a first planar support plate AB2 and a light emitting array AX2 disposed on the first planar support plate AB 2. The light emitting array AX2 comprises a plurality of light emitting line columns AL 1-AL 5 which are vertically distributed in two columns. Wherein, the light emitting line column AL4 located at the 1 st column is partially staggered with both the light emitting line columns AL1 and AL2 located at the 0 th column, and the light emitting line column AL5 located at the 1 st column is partially staggered with both the light emitting line columns AL2 and AL3 located at the 0 th column, so that the resolution of the corresponding formed radar line beam or point cloud of the light emitting units located within the area OL2 in the vertical direction is higher.

In a specific implementation, more light emitting lines may form the light emitting array, and the light emitting lines may have a plurality of positions in the vertical direction based on the difference of the density of the arrangement. As an alternative example, the arrangement density of the plurality of light emission line rows in the vertical direction tends to become smaller uniformly or to become smaller in gradient from the middle to the upper and lower sides, so that the light emission efficiency can be further improved while the detection accuracy is ensured.

As shown in fig. 5B, the light emitting module a3 includes a first planar support plate AB3 and a light emitting array AX3 disposed on the first planar support plate AB 3. The light emitting array AX3 comprises a plurality of light emitting line columns AL 1-AL 6 which are vertically distributed in 3 columns. Unlike the light emission array AX2 shown in fig. 5A, the light emission array AX3 further includes a column of light emission lines AL6 at column 2, and the light emitting line array AL6 is also partially staggered with the light emitting line arrays AL4 and AL5 at the 1 st column, thereby forming a region in which the light-emitting line column AL6 partially crosses both the light-emitting line column AL2 of the 0 th column and the light-emitting line columns AL4 and AL5 of the 1 st column in the vertical direction, to a region in which only the light-emitting line column AL4 of the 1 st column partially crosses the light-emitting line column AL1 of the 0 th column on both upper and lower sides, and the light emission line column AL5 in the 1 st column and the light emission line column AL3 in the 0 th column are partially staggered, and the density is gradually reduced in a gradient manner in the upper and lower sides of the area where the partial light emission units in the light emission line columns AL1 and AL3 in the 0 th column are distributed without any staggering with other columns, the resolution of the emitted light beam of the light emission array AX3 in the vertical direction gradually decreases from the center toward the upper and lower sides.

As another schematic plan view of the light emitting module shown in fig. 5C, the light emitting module a4 includes a first planar support plate AB4 and a light emitting array AX4 disposed on the first planar support plate AB 4. The difference from the light emitting module a3 shown in fig. 5B is that, in the light emitting array AX4, a light emitting line column AL7 located at the 3 rd column is further included, the number of light emitting cells included in the light emitting line column AL7 is different from the number of light emitting cells included in the other several light emitting line columns, which include 4 light emitting cells as shown in fig. 5C, while the other several light emitting line columns AL1 to AL6 each include 8 light emitting line columns, and the light emitting line column AL7 is further staggered in the vertical direction from the light emitting line column AL6 located at the 2 nd column, so that the resolution of the emitted light beam of the light emitting array AX4 in the vertical direction forms a non-uniform distribution that gradually decreases from the middle area to both sides.

In the embodiment of the present invention, the number of the light emitting units included in each light emitting line row is not limited, and the number of the light emitting units in each light emitting line row in the same light emitting array may be the same or different, so that the emission beams of the light emitting modules can be non-uniformly distributed in the vertical direction, and the target detection requirement in a specific application scenario can be met.

In a specific implementation, the plurality of light emitting line columns may be distributed in a plurality of columns along the vertical direction, and the light emitting line columns of adjacent columns may also be staggered with each other in the vertical direction. Fig. 5D is a schematic plan view of a light emitting module, wherein the light emitting module a5 includes a first planar supporting plate AB5 and a light emitting array AX5 disposed on the first planar supporting plate AB 5. The light emission array AX5 includes 3 columns in total, in which a partial area of the light emission line column AL4 located at the 1 st column is partially interleaved with the light emission line column AL1 located at the 0 th column, and another partial area is partially interleaved with the light emission line column AL6 located at the 2 nd column; a part of the light emitting line AL5 in the 1 st column is partially staggered with the light emitting line AL2 in the 0 th column, and the other part of the light emitting line AL7 in the 2 nd column, so that the light emitting array AX5 is distributed in an alternating manner in the vertical direction, and the beam or point cloud of the radar also presents a non-uniform alternating manner.

As described above, in consideration of cost, whether or not the light emitting line columns are staggered and a specific staggered area may be designed according to practical situations. For example, if the light emitting module is used for a laser radar and is installed on a vehicle, the distance measurement in the automatic driving process is realized. For example, the detection requirement is to detect a target within a range of 200 meters. It will be appreciated by those skilled in the art that the detection range capability requirement is positively correlated to vehicle speed, for example, only if vehicle speed is fast and it is generally necessary to see objects more than 200 meters on a highway, so the required range capability of the lidar is directly correlated to vehicle speed, and the greater the vehicle speed, the longer the range that the lidar is expected to detect. The vehicle speed and the road surface inclination angle have correlation, and the larger the inclination angle is, the lower the limit vehicle speed is, because the speed reduction is needed when the vehicle goes up and down the slope based on the driving safety requirement.

In addition, the road slopes of different vehicle speed grades are different according to the design requirements of the road surface. For example, the road surface design parameter information comparison table of different grades in China is shown in the table 1.

Design speed (km/h)	120	100	80	60	40	30	20
								Maximum longitudinal slope (%)	3	4	5	6	7	8	9
Road surface inclination (degree)	1.72	2.29	2.87	3.44	4.01	4.59	5.16

TABLE 1 Chinese road surface design parameter information comparison table for different vehicle speed grades

The most extreme case is assumed to be: the speed of the vehicle is 120km/h road condition, the road surface has an inclination angle, which is assumed to be +/-2 degrees, namely the inclination angle corresponding to the speed of the vehicle of about 120km/h in table 1, wherein +/-2 degrees represents an ascending slope, and-2 degrees represents a descending slope. If it is desired to see the object at 200 meters, the light emission line rows within the range of ± 4 ° of the vertical field of view are all required to be staggered, i.e., the light emission array includes at least two light emission line rows within the range of ± 4 ° of the vertical field of view. As shown in fig. 6, if the vehicle C0 is on the top of a slope and a laser radar (not shown) is horizontally installed on the top or front of the vehicle C0, the distribution density of the light emitting units needs to be increased in the range of the vertical field of view of 0 to-4 ° in order to improve the detection resolution of the object 200 meters ahead.

In a specific application process, in consideration of design margin, the laser radar can be set to perform point cloud encryption within a range of a vertical field angle of +/-5 degrees, and in specific implementation, the light emitting array can increase the density of the light emitting units within the range of the vertical field angle of +/-5 degrees to form an encrypted area, so that the detection efficiency can be improved.

In some embodiments of the present invention, in the light emitting array, the plurality of light emitting line rows may be distributed in a plurality of columns in a vertical direction, and for the light emitting line row located at an opposite middle region in the first planar support plate, one end thereof may be connected end to end with the light emitting line row of the adjacent column, and the other end thereof may be vertically staggered with the light emitting line row of the adjacent column.

As shown in fig. 2A, in the light emission array AX0, a plurality of light emitting cells located at the upper end portion of the light emission line column AL3 of the 1 st column are interleaved with the VA0 region in the vertical direction located at the light emission line column AL1 of the 0 th column, constituting an encrypted one-dimensional array region; the lower end part of the light emitting line array AL3 in the 1 st column is connected with the light emitting line array AL2 in the 0 th column end to form a relatively sparse one-dimensional array area.

As also shown in fig. 5D, in the light emission array AX5, the light emission line row AL4 located at the 1 st column has its upper end portion staggered in the vertical direction from the light emission line row AL1 located at the 0 th column; the lower end part of the light emitting line is intersected with the light emitting line AL2 in the 0 th column in the vertical direction, and is intersected with the light emitting line AL6 in the 2 nd column in the vertical direction. Similarly, the light-emitting line array AL5 located at the 1 st column has its upper end portion staggered with respect to the light-emitting line array AL2 located at the 0 th column in the vertical direction; the lower end part of the light emitting line is intersected with the light emitting line AL3 in the 0 th column in the vertical direction, and is intersected with the light emitting line AL7 in the 2 nd column in the vertical direction. The arrangement mode forms a one-dimensional array distributed at intervals.

In a specific implementation, the light emitting units in the light emitting line array have the same pitch, as shown in fig. 2A, 4A, and 5A to 5D, or may be non-uniformly distributed, which is described below with reference to the accompanying drawings.

Referring to the schematic plane structure of the light emitting module shown in fig. 7A, the light emitting module a6 includes a first plane supporting plate AB6 and a light emitting array AX6 disposed on the first plane supporting plate AB6, wherein the light emitting array AX6 includes light emitting line columns AL1 and AL2 in the 0 th column and a light emitting line column AL3 in the 1 st column, which is different from the previous embodiments in that the intervals between the light emitting units AU included in the light emitting line columns AL1 and AL2 in the 0 th column are different, and the intervals between the light emitting units AU in the light emitting line column AL3 in the 1 st column are the same.

In a specific implementation, the distance between the light emitting units in the light emitting line array tends to change uniformly or in a gradient manner. As some alternative examples, the pitches of the light emitting units in the plurality of light emitting line columns are in an increasing trend from the center to both sides, or from one end to the other end. With continued reference to fig. 7A, in the light-emission line array AL1, the intervals between the light-emission units AU in the light-emission line array AL1 gradually increase from the lower end portion toward the upper end portion, and the intervals between the light-emission units AU in the light-emission line array AL2 gradually increase from the upper end portion toward the lower end portion.

As shown in fig. 7B, in the light emitting module a7, the light emitting array AX7 disposed on the first planar support plate AB7 includes a0 th row of oppositely symmetric light emitting line arrays AL1 and AL2 and a1 st row of light emitting line arrays AL3, and the light emitting cells in the light emitting line arrays AL1 to AL3 are non-uniformly arranged.

As shown in fig. 7B, the light emitting units AU in the 0 th column collectively form an arrangement structure with gradually increasing intervals from the middle region of the first planar supporting plate AB7 to the upper and lower sides, while in the 1 st column, the light emitting lines AL3 on the one hand are respectively staggered with the light emitting lines AL1 and AL2 in the 0 th column in the vertical direction, and the intervals of the light emitting units AU in the light emitting lines AL3 gradually increase from the lower side to the upper side in the vertical direction, so that the non-uniform distribution of the light beams of the light emitting array AX7 and the entire line beams and point clouds of the radar in the vertical direction is formed, and the arrangement with gradually decreasing density from the middle lower region to both sides is integrally formed.

With respect to the light emitting module A8, referring to fig. 7C, in the light emitting array AX8 disposed on the first planar supporting plate AB8, the light emitting units in the light emitting line rows AL1 to AL3 are also non-uniformly arranged. As shown in fig. 7C, the light emitting units AU in the light emitting line columns AL1 and AL2 of the 0 th column are arranged in an arrangement structure with gradually increasing intervals from the lower end to the upper end in the vertical direction, while in the 1 st column, the light emitting units AU in the light emitting line column AL3 are arranged in an arrangement structure with gradually increasing intervals from the upper end to the lower end in the vertical direction, and the light emitting line columns AL3 are respectively staggered with the light emitting line columns AL1 and AL2 of the 0 th column in the vertical direction, so that the emitted light beams of the light emitting array AX8 are non-uniformly distributed in the vertical direction.

In the specific implementation, enough routing space is reserved between each light emitting line row in the light emitting array according to the process requirements.

Wherein, in a specific application process, the pitch of the array formed by the plurality of light emitting line columns is equal to the pitch of a single light emitting line column divided by the number of staggered columns. Wherein, as shown in fig. 2A, the pitch of a single light-emitting line column refers to the spacing between two adjacent light-emitting units located in the same column, as the first pitch pt0 in fig. 2A; the pitch of the light emission array refers to a distance between light emission units adjacent in the vertical direction in two columns of light emission lines staggered in the vertical direction, and as the second pitch pt1 in fig. 2A, pt1 is pt 0/2.

In a specific implementation, each light emitting line column can be independently packaged as a chip or device. In view of the yield of semiconductor devices, the aspect ratio of each light emitting line column needs to be limited. In the embodiment of the present invention, the aspect ratio of the adopted light emitting line array may be set to be 1:1 to 10:1, and in a specific application scenario, the light emitting array may need to form a 30:1 or even 60:1 one-dimensional array, for this reason, by adopting a multi-segment splicing manner of multiple light emitting line arrays in the embodiment of the present invention, the requirement of product yield may be met, and higher cost performance may be achieved.

In addition, in order to improve the distance measurement capability as much as possible, the light emitting area of the light emitting module needs to be as large as possible, especially when a VCSEL is used as the light source. In this case, it may be allowable that the height H of the light emitting region in the vertical direction is larger than the encryption pitch, that is, some overlapping portions of the light spots appear after the columns are staggered. Due to the diffraction phenomenon of light, a situation that two adjacent light spots cannot be distinguished visually may occur, for example, in the light spot schematic diagram of the encrypted adjacent laser shown in fig. 8, according to Rayleigh Criterion (Rayleigh Criterion), when the coincidence degree R of the two light spots is less than 50%, that is, the full width at half maximum H/2 of the main lobe of the light spot is equal to the distance R0 between the adjacent light spots without considering side lobes, that is, H/2 is equal to R0, the two light spots can still be visually separated, therefore, when the system resolution of the light emitting module reaches the diffraction limit, the coincidence degree R of the light spots of the adjacent light emitting units can be set to be smaller than the center distance R0 of the adjacent two light emitting units, so that the energy density of the light emitting module can be improved as much as possible while the high resolution is maintained, and the ranging capability is further improved.

In a specific implementation, the plurality of light emitting line arrays disposed on the first planar supporting plate may have the same specification or different specifications. As shown in the foregoing embodiment, referring to fig. 5C, the light emission line array AL7 includes a different number of light emission cells from the other light emission line arrays in the light emission array AX 4. As also shown in fig. 7A, the light-emission line array AL3 differs in pitch from the light-emission cells in the other light-emission line arrays in the light-emission array AX 6. Also for example the size of each light emitting cell in a column of light emitting lines may be different. It is understood that the above is only an example, and the light emitting lines arranged on the same first planar supporting plate may have different specification parameters according to the requirement.

In order to make the embodiments of the present invention better understood and implemented by those skilled in the art, some specific realizable examples of the light emitting unit are shown below.

The light emitting unit may specifically include one light emitting point, or may include a plurality of light emitting points.

In a specific implementation, the respective cathodes or anodes of a plurality of the light emitting units may be common, and each light emitting unit has a connection point electrically connected to the anode or cathode not common to each corresponding light emitting unit, respectively. The connection point may be a wire bonding pad or other types of connection components.

In some embodiments of the present invention, the light emitting unit may include a plurality of light emitting blocks, wherein each of the light emitting blocks includes at least one light emitting point.

Referring to a structure diagram of a light emitting unit shown in fig. 9, the light emitting unit AU0 includes two light emitting blocks, i.e., a light emitting block U1 and a light emitting block U2, the cathodes of the light emitting blocks U1 and U2 are shared, the light emitting block U1 has a connection point U1a, and the light emitting block U2 has a connection point U2 a. In an implementation, the light emitting unit AU0 may be an independently packaged laser, in which the light emitting block U1 and the light emitting block U2 are respectively provided with separate substrates. As an alternative example, the light emitting unit AU0 may be a VCSEL, PCSEL, or other vertical cavity light emitting device.

Referring to the schematic structure of the light emission line array shown in fig. 10, the light emission line array ALi includes a plurality of light emission units AU0, the light emission units AU0 adopt the structure of the light emission units shown in fig. 9, and the intervals between the light emission units AU0 are the same. It will be appreciated that in particular implementations the spacing between the light emission units AU0 may also be different.

In a specific application process, according to actual needs of an actual detection application scene, the control device and the driving device can be adopted to drive and control the light emitting module, and the control device can output a control signal to control the on-off of the driving device so as to drive the light emitting module to emit light in a corresponding emitting channel. Wherein, one driving device can be used to control whether the light emitting units of the plurality of light emitting line columns emit light or not; different driving devices can be adopted to respectively control different light emitting line columns; or a plurality of driving devices are adopted, and each driving device respectively controls whether a plurality of light emitting line columns emit light or not.

For a better understanding and implementation by those skilled in the art, a specific implementation of some of the light emitting modules using the light emitting line array shown in fig. 10 is shown below.

First, as a schematic plan structure of the light emitting module shown in fig. 11A, the light emitting module a9 includes a first planar supporting plate AB9, and a light emitting array AX9 and a driving chip CH0 disposed thereon.

In an implementation, the control device (not shown) may be disposed on another circuit board, and may also be disposed on the first planar supporting plate AB 9. The control device may be implemented by a single chip, a CPU, a programmable logic array (FPGA) chip, or the like, and the embodiment of the present invention does not limit the specific implementation form of the control device.

With continued reference to fig. 11A, light emission array AX9 includes light emission line array AL1 in column 0 and light emission line array AL2 in column 1, and light emission line array AL2 and light emission line array AL1 are partially staggered in the vertical direction, so that non-uniform distribution of the laser radar beam and the point cloud over the vertical field of view can be achieved, wherein the vertical field of view density of the emission beam in the vertically staggered area of light emission line array AL2 and light emission line array AL1 is greater than the vertical field of view density in the non-staggered area of the two.

In a specific implementation, single-side driving can be performed, namely, a driver is positioned on a single side of a laser, so that the area can be saved. As shown in fig. 11A, the electrical connection of the driver chip CH0 and each light emission unit AU0 can be accomplished by wiring inside the first planar support plate AB9 by making electrical connection with connection points (not shown) of the driver chip CH0 and connection points of each light emission unit AU0 in the light emission line columns AL1, AL2, respectively.

In other embodiments of the present invention, a plurality of driving chips may be employed, each driving 1 or more light emitting line columns, respectively.

In the specific implementation, double-side driving can also be performed, namely, drivers are positioned on two sides of the laser, so that the driving capability can be improved. Referring to a schematic plan view of the light emitting module shown in fig. 11B, the light emitting module a10 includes: the first planar supporting plate AB10, and the light emitting array AX10 and the driving chips CH1, CH2 disposed thereon. The light emitting array AX10 includes a light emitting line column AL1 located in the 0 th column and a light emitting line column AL2 located in the 1 st column, a driving chip CH1 is used for driving the light emitting line column AL1, a driving chip CH2 is used for driving the light emitting line column AL2, and the light emitting line column AL2 and the light emitting line column AL1 are partially staggered in the vertical direction, so that non-uniform distribution of the emitted light beams over the vertical field of view can be achieved, wherein the vertical field of view density of the emitted light beams in the region where the light emitting line column AL2 and the light emitting line column AL1 are staggered in the vertical direction is greater than that in the region where the two are not staggered.

The difference from the light emitting module shown in fig. 11A is also that, on the one hand, the light emitting regions of the light emitting units AU0 in the light emission line array AL1 and the light emission line array AL2 are more concentrated, so that the energy density of the light emission array as a whole can be further improved; on the other hand, the connection points of the light emitting units AU0 are disposed on two sides of the light emitting array AX10 and closer to their respective driver chips, so that the routing resistance in the first panel AB10 can be reduced, and the coupling noise interference between the lines can be reduced.

It should be noted that the above drawings are only schematic structures for easy understanding, and do not represent actual structures of the optical transmission module, for example, the actual relative size proportion relationship or the number correspondence relationship between the driving chip and the laser in fig. 11A and 11B, and this is not limited in this embodiment of the present specification.

As described above, the embodiment of the present invention further provides a light detection module corresponding to the light emitting module in the foregoing embodiment. The light detection module and the light emission module may have the same layout structure. In a specific application, the light emitting module and the light detecting module can be applied to a laser radar to realize target detection in a target field of view.

In some embodiments of the present invention, there is provided a light detection module comprising: a second planar support plate; the plurality of optical detection lines form an optical detection array which is arranged on the second plane supporting plate, each optical detection line comprises a plurality of optical detection units, and the optical detection units in at least two optical detection lines are partially staggered with each other and are in non-uniform distribution in the vertical direction.

As some alternative examples, the plurality of light detection line columns are arranged such that the density of light detection units near the middle region of the second planar support plate in the vertical direction is greater than the density of light detection units near the upper and lower sides.

In a specific implementation, the plurality of optical detection lines in the optical detection array are distributed in multiple rows, and the optical detection units in different optical detection lines are located in different rows.

Based on the basic detection implementation principle of radar, in order to realize target detection in a target field of view, at least part of the field of view of a transmitting end and a receiving end of the radar are overlapped, so that a receiving channel and a transmitting channel can correspond to each other, and the receiving end and the transmitting end can be symmetrically arranged, so that an optical detection module of the receiving end is also suitable for adopting a setting layout mode similar to that of an optical detection module of the transmitting end, and therefore different setting layout embodiments of the transmitting end and the structure of an attached figure are also suitable for the structure of the optical detection module of the receiving end, which can be referred to the specific embodiment and the attached figure of the optical detection module specifically and are not described herein again.

As mentioned above, the optical transmitting module has a wide application field, wherein the optical transmitting module can be applied to the fields of target detection and control, etc., and for better understanding and implementation in the technical field of the field, the following description is given by taking its specific application in the laser radar as an example.

Referring to the schematic structural diagram of the lidar shown in fig. 12, the lidar L0 may include: the optical transceiver comprises an optical transmitting module TX and an optical detecting module RX which is correspondingly arranged with the optical transmitting module TX.

Wherein, the optical transmission module TX is disposed on a focal plane of the transmitting end, and may include:

a first planar support plate ABX;

a plurality of light emitting line arrays ALx constituting a light emitting array disposed on the first planar support plate ABX, each light emitting line array ALx including a plurality of light emitting cells; the light emitting direction of the light emitting units is perpendicular to the first plane support plate ABX, and the light emitting unit parts in at least two light emitting line rows are mutually staggered to form non-uniform distribution in the vertical direction.

The specific implementation, operation principle, advantages, etc. of the light emitting array in the light emitting module TX disposed on the first planar support plate to form a planar emitting device can be referred to the detailed description of the foregoing embodiments, and will not be described in detail herein.

With continued reference to fig. 12, in an implementation, the optical detection module RX is disposed on a focal plane of the receiving end, and may specifically include:

a second planar support panel PBX;

the plurality of optical detection lines RLx form an optical detection array and are arranged on the second plane supporting plate PBX, the optical detection lines RLx comprise a plurality of optical detection units, and the optical detection units in at least two optical detection lines RLx are partially staggered with each other and form non-uniform distribution in the vertical direction.

The optical detection array in the optical detection module TX is disposed on the second planar support plate to form a planar receiving device.

By adopting the laser radar, each light detection line RLx corresponds to the corresponding light emission line ALx, the light emission module TX emits a detection light beam, and an echo light beam reflected by the target object O is received by the light detection module RX and converted into an electric signal for target detection.

The light emitting module and the light detecting module are arranged correspondingly in layout, and the point cloud view fields of the light emitting module and the light detecting module are ensured to be overlapped, so that light emitted by the light emitting module can be received by the corresponding light detecting module after being reflected by an external obstacle.

As an optional example, the optical detection unit may specifically be a Single Photon detection unit, such as a Single Photon Avalanche photodiode (SPAD) array or a silicon Photomultiplier (SiPM), so as to improve detection sensitivity and achieve detection of an extremely weak target signal.

Referring to the schematic structural diagram of an optical detection line array shown in fig. 13, the optical detection line array RLi includes a plurality of optical detection units RU, each of the optical detection units RU may be uniformly or non-uniformly arranged, and specific specification parameters of the optical detection line array RLi may be set with reference to a corresponding optical emission line array Ali, including at least one specification parameter of a specific number of the optical detection units RU, a specific size of each optical detection unit RU, a distance between each optical detection unit RU, a line distance between each optical detection line array, a specific arrangement manner between each optical detection line array, and the like included in the optical detection units RLi, as long as at least partial field of view coincidence is ensured at the transceiving ends, so that light emitted from the optical emission units after being reflected by an obstacle can be at least partially received by the optical detection units (e.g., detectors), and information such as distance and reflectivity of the obstacle can be analyzed, thereby enabling detection of the obstacle.

In a specific implementation, with continued reference to fig. 13, each light detection unit RU may include a detection block Ra and a connection point Rb, and at least one light detection unit RU and one light emission unit AU may constitute one detection channel. The connection point Rb may be a wire bonding pad or other types of connection components.

As described above, the specific structure of the light detection module and the specific structure of the light emitting module are consistent and are correspondingly arranged. In order to make it better understood and implemented by those skilled in the art, some alternative examples are given below.

Referring to the schematic plan structure of the light detection module shown in fig. 14A and 14B, first, as shown in fig. 14A, the light detection module B0 includes a second planar support plate PB0 and a light detection array RX0 disposed on the second planar support plate PB 0. The light detection array RX0 includes a plurality of light detection line rows RL 1-RL 2, which are divided into 2 rows and vertically distributed. In addition, a part of the light detection line array RL2 in the 1 st column is interlaced with the light detection line array RL1 in the 0 th column in the vertical direction, and accordingly, the resolution of the system corresponding to the interlaced area in the vertical direction is higher than the resolution of the other non-interlaced areas, so that the overall detection capability and detection accuracy of the system can be improved, and the overall power consumption of the system can be considered.

Wherein the light detection line arrays RL1 and RL2 are both arranged in the same direction, i.e., the connection points of the respective light detection units are closer to the left side of the second planar support plate PB0, and the corresponding detection points are closer to the right side of the second planar support plate PB 0.

As a specific example, the light detection module B0 shown in fig. 14A may be provided in a laser radar in a matching manner with the light emission module a9 of an arrangement similar to that shown in fig. 11A for target detection.

Referring to the schematic structural diagram of the light detection module shown in fig. 14B, the light detection module B1 includes a second planar support plate PB1 and a light detection array RX1 disposed on the second planar support plate PB 1. The light detection array RX0 includes a plurality of light detection line rows RL 1-RL 2, which are divided into 2 rows and vertically distributed. In addition, a part of the light detection line array RL2 in the 1 st column is interlaced with the light detection line array RL1 in the 0 th column in the vertical direction, and accordingly, the resolution of the system corresponding to the interlaced area in the vertical direction is higher than the resolution of the other non-interlaced areas, so that the overall detection capability and detection accuracy of the system can be improved, and the overall power consumption of the system can be considered.

The difference from the light detection module shown in fig. 14A is that the light detection line array RL1 and the light detection line array RL2 are symmetrically arranged along the vertical center line C-C, that is, the connection points of the light detection units in the 0 th light detection line array RL1 are all closer to the left side of the second planar support plate PB1, and the corresponding detection points are closer to the right side of the second planar support plate PB 1; while the connection points of the light detection units in the 1 st column of light detection lines RL2 are all closer to the right side of the second planar support plate PB1 and the corresponding detection points are closer to the left side of the second planar support plate PB 1.

As a specific example, the light detection module B1 shown in fig. 14B may be provided in a laser radar in a manner matching the light emission module a10 of fig. 11B or a similar configuration to fig. 11B for object detection.

In summary, the lidar in the embodiments of the present description may implement non-uniform point clouds by planarizing (e.g., placing the transceiver on a planar support plate).

In order to improve the light accuracy and ensure the consistency and stability of the distance measuring capability of each transceiver channel, in a specific application process, the view fields of a light emitting module and a light detecting module in a laser radar may be relatively vertically staggered, and the view field size of the light emitting module in a first direction is larger than that of the light receiving module, the view field size in a second direction is smaller than that of the light detecting module, and the first direction is perpendicular to the second direction.

With continued reference to fig. 12, if the fields of view of the optical transmitter TX and the optical detector RX are mutually staggered, a certain overlapping area, i.e. an effective field of view, is formed.

For example, if the coverage areas of the fields of view of the optical transmitter TX and the optical detector RX are both rectangular, the first direction and the second direction respectively correspond to two perpendicular side length directions. And the size of the field of view of the light emitting module TX in the first direction is V1, the size of the field of view in the second direction is H1, the size of the field of view of the light detecting module RX in the first direction is V2, and the size of the field of view in the second direction is H2, then V1 > V2, and H1 < H2. The light emitting module TX and the light detecting module RX respectively adopt the field sizes, and the corresponding effective field area is V2 × H1/f²Wherein f is the focal length.

Referring to fig. 15A and 15B, an alternative exemplary view of the relationship of the fields of view of the light emitting module and the light detecting module is shown. The coverage areas of the fields of view of the optical transmission module TX and the optical detection module RX are both rectangular.

Referring first to an example of a view field relationship of the optical transmission module TX and the optical detection module RX shown in fig. 15A, assuming that the first direction is a horizontal direction, the second direction is a vertical direction, and a horizontal direction size of a view field Aa of the optical transmission module TX is V1_AVertical dimension H1_A，V1_A＞H1_AThe horizontal dimension of the field of view Ba of the light detection module RX is V2_AVertical dimension H2_AAnd H2_A＞V2_A. As shown in fig. 15A, in the horizontal direction, the size V1 of the field of view of the light emitting module TX_ALarger than the field size V2 of the light detection module RX_AI.e. V1_A＞V2_A(ii) a In the vertical direction, the size of the field of view H1 of the optical transmit module TX_ASmaller than the field size H2 of the light detection module RX_AI.e. H1_A＜H2_A。

Referring next to another view field relationship example of the light emitting module TX and the light detecting module RX shown in fig. 15B, assuming that the first direction is a vertical direction, the second direction is a horizontal direction, and the horizontal direction size of the view field Ab of the light emitting module TX is V1_BVertical dimension H1_B，V1_B＜H1_BThe horizontal dimension of the field Bb of the light detection module RX is V2_BVertical dimension H2_BAnd H2_B＜V2_B. As shown in fig. 15B, in the horizontal direction, the size V1 of the field of view of the light emitting module TX_BSmaller than the field size V2 of the light detection module RX_BI.e. V1_B＜V2_B(ii) a In the vertical direction, the size of the field of view of the light emitting module A H1_BField size of light detection Module B H2_BI.e. H1_B＞H2_B。

As can be seen from the above example, with the above optical transceiver module, the main energy of the light spot returned by the probe beam emitted by the light emitting module TX is distributed over the effective area of the light detecting module RX, so as to form an approximate cross shape, and if the light spot of the light emitting module TX is wider than the width of the light detecting module RX in the horizontal direction, the light spot of the light emitting module TX is smaller than the width of the light detecting module RX in the vertical direction; if the optical transmit module TX spot is smaller in width than the optical detection module RX in the horizontal direction, the optical transmit module TX spot is smaller than the optical detection module RX in the vertical direction. Like this, when there is optics, structure, paster, temperature drift etc. to the light error, still can keep same coincidence area and range finding ability, therefore can improve to the light precision, and then guarantee the uniformity and the stability of the range finding ability of each transceiver channel.

By adopting the laser radar, from the perspective of the effect of the light allowance, the allowable errors of the light emitting module and the light detection module in the first direction and the second direction are consistent, so that the design allowance of the light emitting surface of the light emitting module and the photosensitive surface of the light detection module can be improved, the light accuracy can be improved, and the consistency and the stability of the ranging capability of each channel can be further ensured.

In a specific implementation, the fields of view of the respective light detection units and the respective light emission units may be vertically staggered relatively, and the field of view size of each light emission unit in the first direction is larger than that of the corresponding detection unit, and the field of view size in the second direction is smaller than that of the corresponding detection unit.

When there are optics, the structure, the paster, the temperature floats when focusing on light error, through making each light detection unit and the equal mutually perpendicular crisscross of the visual field that each corresponding light emission unit corresponds, and satisfy above-mentioned size corresponding relation, can make the point cloud that each detection passageway detected, also be the effective area of every point cloud on the focal plane, perhaps the effective detection angle scope of every point cloud of laser radar all can keep same coincidence area and range finding ability, therefore can improve the precision of focusing on light, and then guarantee the uniformity and the stability of the range finding ability of each transceiver channel.

In some embodiments of the present invention, a light detection unit RU0 as shown in fig. 16 may be employed corresponding to the light emission unit AU0 shown in fig. 9. Specifically, the light detection unit RU0 includes two detection blocks and corresponding connection points, namely a detection block Ra1 and a detection block Ra2, and a connection point Rb1 corresponding to the detection block Ra1 and a connection point Rb2 corresponding to the detection block Ra 2.

It is to be understood that a detection unit may also comprise only one detection block. Whether a detection unit includes several detection blocks, one detection block may correspond to one or more light-emitting blocks, or one light-emitting block may correspond to a plurality of detection blocks.

In some embodiments of the present invention, the plurality of light emitting line rows in the light emitting module are distributed in a plurality of columns along the vertical direction, and the plurality of light emitting line rows may be at least partially staggered, so as to change the distribution density of the emitted light beams in the vertical field of view; correspondingly, a plurality of detection units in the optical detection module are distributed in a plurality of rows, and a plurality of rows of optical detection lines are at least partially staggered, and each row of optical detection lines is vertically staggered with the view field of the corresponding light emission line. If the light emitting unit includes a plurality of light emitting blocks, each light emitting block has a detection block with a field of view vertically staggered with it.

From the perspective of the effect of the light margin, each light emitting unit and each light detecting unit have certain allowable errors in the horizontal direction or the vertical direction, and the allowable errors in the two directions are consistent, so that the total design margin of the light emitting surface of the light emitting module and the light sensitive surface of the light detecting module can be improved, the light precision can be further improved, and the consistency and the stability of the distance measuring capability of each channel can be ensured.

Moreover, the nonuniform distribution of the wire harness on the vertical field of view is realized through the staggered distribution of a plurality of rows of light emitting lines of the light emitting modules and the staggered distribution of a plurality of rows of light receiving lines in the light detecting modules corresponding to the light emitting modules, the vertical direction resolution of the light emitting modules and the laser radar comprising the light emitting modules in a target area can be improved, and the density of the laser point cloud obtained by detection can be improved with lower cost.

In addition, in the laser radar in the embodiment of the present invention, the transmitting end and the receiving end both adopt the planar design, so that the transmitting end and the receiving end can use symmetrical optical paths, the light efficiency is very high, and the transmitting and receiving planar support plates (i.e. the first planar support plate and the second planar support plate) are perpendicular to the optical axis, when the optical mechanical structure slightly deforms due to temperature or stress, especially the warping of the circuit board itself, no serious light position change is caused, that is, the corresponding relationship of the transmitting and receiving channels is basically stable. Therefore, as long as enough patch precision is ensured, the whole light focusing can be realized, and the installation and adjustment time is greatly saved. In addition, the laser does not need to point to the heart, but only a telecentric light path is used in cooperation, namely, a field lens is placed near a focal plane, and the light path is pulled back to the optical axis, so that the chip mounting efficiency of the laser can be improved. Referring to fig. 3A and 3B, the optical path of the optical transmission module at the transmission end is schematically illustrated.

For those skilled in the art to understand and implement, the following briefly introduces a ranging method corresponding to the lidar, and with reference to a flowchart of the lidar ranging method shown in fig. 19, the method may specifically include the following steps:

and S11, respectively controlling the light emitting array to emit light pulses and the light detecting array to receive the light reflected by the external obstacle.

Wherein, the light emitting array and the light detecting array are correspondingly arranged. The light emitting array can comprise a plurality of light emitting line rows, each light emitting line row is arranged on a first plane, each light emitting line row comprises a plurality of light emitting units, the light emitting directions of the light emitting units are vertical to the first plane, and the light emitting units are non-uniformly distributed in the vertical direction; the light detection array may include a plurality of light detection line arrays, each of the light detection line arrays being disposed on the second plane, each of the light detection line arrays including a plurality of light detection units.

In a specific implementation, in the light emitting array, the light emitting unit parts in at least two light emitting line columns are mutually staggered and form non-uniform distribution in the vertical direction; accordingly, in the light detection array, the light detection unit portions in at least two light detection line columns may be staggered with each other to form a non-uniform distribution in the vertical direction.

Specific implementations of the light emitting array and the light detecting array can be found in the detailed descriptions of the embodiments of the light emitting module and the light detecting module, which are not described in detail herein.

And S12, calculating the position information of the obstacle according to the detection data of the light detection array, combining the detection data of the light detection array in the full view field range into a frame, and outputting the frame as a point cloud.

Wherein the full field of view range includes a horizontal field of view and a vertical field of view.

As an alternative example, the lidar may specifically be a horizontal scanning mechanical radar. With the laser radar in the embodiment of the present invention, since the light emitting module includes a plurality of light emitting line arrays located in different rows, and the corresponding light detecting module includes a plurality of light detecting line arrays located in different rows, in order to make those skilled in the art better understand how to generate the point cloud data, first, the operation principle of the mechanical radar for horizontal scanning is briefly described below.

First, the angular velocity ω of the radar is 360 ° fr, where fr is the rotational frequency, and as an example, when the rotational frequency of the mechanical radar is 20HZ, ω is 7200 °/s. The scanning period T is repeated, which means the minimum time slice for completing the measurement of all channels, and all channels are repeatedly scanned at this period. When the scan frequency is the same for all channels, or the horizontal angular resolution HRES is the same, HRES ═ ω T.

Due to the rotational inertia of the mechanical radar, the scanning angular velocity ω can be considered to be constant within the range of the angular resolution, and therefore, the mechanical angle at a certain time can be predicted by using the formula Φ 0+ ω Δ T, where Φ is the mechanical angle at the current lighting time, Φ 0 is the mechanical angle at the previous lighting time, and Δ T is a value in a time sequence table, that is, a time difference between the real lighting time of the point cloud data and the previous measurement time.

In a specific implementation, the lidar may be configured to emit light for all channels simultaneously, or may be configured to emit light for all channels non-simultaneously (e.g., in a round trip manner).

First, refer to a schematic diagram of the correspondence between the horizontal scanning process and the generated point cloud during non-round emission as shown in fig. 17A and fig. 18AThe schematic diagram of the corresponding relationship between the horizontal scanning process and the generated point cloud during the round trip light emission is shown, and as an example, the center distance Gap between two adjacent light emission lines bank a and bank b in the horizontal direction can be in the order of cm; the angle between the two in the horizontal direction is x °, which is greater than the horizontal angular resolution, and as some optional embodiments, the specific value may be, for example, 3 °, 10 °, 12 °. The Pitch of the light emitting cells Pitch in each light emitting line column is in the order of μm. In fig. 17A, the non-round emission, that is, the correspondence between the horizontal scanning process and the generated point cloud when all the channels emit light simultaneously is shown, where the horizontal angles corresponding to the time t1 are θ_i、Φ_iRespectively scanning to obtain corresponding point cloud sequences, and after the duration of omega x T, namely at the time of T2, simultaneously illuminating each light emitting unit in the light emitting line arrays Bank A and Bank B again, and scanning to obtain horizontal angles theta_i+1、Φ_i+1The horizontal angular resolution of the two scans at times T1 and T2 is T2-T1 ═ ω T ═ HRES.

Fig. 18A is a schematic diagram showing a corresponding relationship between the horizontal scanning process and the generated point cloud when the light emission units emit light in round trips of each channel, and since the light emission units emit light non-simultaneously, as shown in fig. 18A, if the light emission units in the light emission lines bank a and bank b emit light sequentially in the order from top to bottom, for example, in the Vx direction, from top to bottom, and in time sequence, at time T1, the first light emission unit in the light emission lines bank a and bank b emits light, at time T ', the second light emission unit in the light emission lines bank a and bank b emits light, at time T ", the third light emission unit in the light emission lines bank a and bank b emits light, and at time T' ″, the fourth light emission unit in the light emission lines bank a and bank b emits light, the point cloud corresponding to each light emission unit in the same light emission line has a certain offset in the horizontal direction, as shown in fig. 18A.

Next, referring to a schematic diagram of a correspondence relationship between a channel and a point cloud when the horizontal scanning type mechanical radar emits light without polling and a schematic diagram of a correspondence relationship between a channel and a point cloud when the horizontal scanning type mechanical radar emits light with polling as shown in fig. 18B, where a light emitting module TX and a light detecting module of the laser radar are correspondingly disposed, the light emitting module includes light emitting line arrays TL1 to TL4 that are non-uniformly arranged in the vertical direction, each light emitting line array includes a plurality of light emitting units, correspondingly, the light detecting module RX includes light detecting line arrays RL1 to RL4 that are non-uniformly arranged in the vertical direction, and each light detecting line array includes a plurality of detecting units (e.g., detectors). If the light emitting units (e.g., lasers) in each of the light emitting line TL 1-TL 4 emit light simultaneously, the corresponding light detecting modules RX detect the light.

The light emitting unit (laser) is referred to as the smallest addressable unit, for example, a VCSEL has a plurality of light emitting holes for emitting light simultaneously, which can only be combined to form one light emitting unit, and only a single or a partial group of lasers can be addressed and selected to form a plurality of light emitting units. Likewise, the light detecting unit (e.g. detector) is also referred to as the smallest addressable unit. If the multiplexing condition exists, the multiplexing units are coupled by using a wire.

With continued reference to fig. 17B, in the middle is the point cloud field angle, the horizontal position of each point represents the horizontal angle θ, and the vertical position represents the pitch angle γ, where γ ═ β. The horizontal angle shifts with the rotation of the radar rotor, and θ is α + ω (n × T + Δ Ti), where Δ Ti is the time delay of the ith channel relative to the previous measurement time, α is the horizontal angle of the previous measurement time, and T is the minimum time slice T for completing the full channel scanning, so that, in combination with the horizontal angle θ and the pitch angle γ, for non-round-trip lighting, a cloud point map of a part of a frame (the vertical field of view completely corresponds to the vertical FoV of the radar, and the horizontal field of view only shows data of 3 scanning time slices T) can be generated as shown in fig. 17B; for the round trip lighting, a cloud of points is generated for a portion of a frame as shown in fig. 18B, the vertical field of view corresponds entirely to the vertical FoV of the radar, and the horizontal field of view only shows data for 3 scan time slices T.

Although the embodiments of the present invention have been disclosed, the present invention is not limited thereto. Various changes and modifications may be effected therein by one skilled in the art without departing from the spirit and scope of the utility model as defined in the appended claims.

Claims

1. An optical transmit module, comprising:

a first planar support plate;

2. The optical transmit module of claim 1, wherein the plurality of optical transmit lines are arranged such that a density of the optical transmit units in a vertical direction near a middle region of the first planar support plate is greater than a density of the optical transmit units near upper and lower sides.

3. The optical transmit module of claim 2, wherein the arrangement density of the plurality of optical transmit lines in the vertical direction is reduced from the middle to the upper and lower sides in a uniform manner or in a gradient manner.

4. The optical transmit module of claim 2, wherein the optical transmit array is an encrypted area of optical transmit units within ± 5 ° of vertical field angle.

5. The optical transmit module of claim 2, wherein the plurality of optical transmit lines are arranged in a plurality of rows, and the optical transmit units in different optical transmit lines are located in different rows.

6. The optical transmit module of claim 1, wherein the spacing between the optical transmit units in the optical transmit line array is the same or non-uniform.

7. The optical transmit module of claim 1, wherein the optical transmit module is used in a lidar and is disposed at a focal plane of a transmitting end of the lidar, and further comprising a field lens adapted to converge light emitted from the optical transmit unit so as to pull the light emitted from the optical transmit unit back to an optical axis of the transmitting end.

8. The light emitting module of claim 7, further comprising a lens assembly adapted to deflect light exiting the light emitting unit such that light exiting lasers that are each emitting light perpendicular to the first planar support plate can cover the entire vertical field of view of the lidar.

9. The optical transmit module of claim 1, wherein the pitch of the optical transmit array formed by the plurality of optical transmit columns is greater than or equal to the pitch of a single optical transmit column divided by the number of staggered columns.

10. The optical transmit module of claim 1, wherein the overlapping ratio of the light spots of the adjacent light transmit units is slightly smaller than the center distance between the two adjacent light transmit units.

11. The optical transmit module of claim 1, wherein the optical transmit unit comprises at least one of: vertical cavity surface emitting lasers, photonic crystal surface emitting semiconductor lasers.

12. The optical transmit module of any of claims 1-11, wherein the plurality of optical transmit line arrays disposed on the first planar support plate have the same gauge or have different gauges.

13. A light detection module, comprising:

a second planar support plate;

14. The light detection module of claim 13, wherein the plurality of light detection line arrays are arranged such that a density of light detection units near a middle region of the second planar support plate in a vertical direction is greater than a density of light detection units near upper and lower sides.

15. The light detection module of claim 13, wherein the light detection module is used for a lidar and is disposed at a focal plane position of a receiving end of the lidar, and further comprises a diaphragm and a filter, wherein:

the diaphragm is suitable for blocking stray light;

16. A lidar, comprising: light emission module and with the light detection module that light emission module corresponds the arrangement, wherein:

a first planar support plate;

a second planar support plate;