Lidar assembly method and lidar

Abstract

The application relates to an assembly method of a laser radar and the laser radar; the assembly method comprises the following steps: acquiring multiple filters, the combination of the wavelength ranges allowed to pass through the multiple filters covering an emission wavelength range; detecting an actual emission wavelength of the outgoing laser; and selecting a filter with a central wavelength matched with the actual emission wavelength from the multiple filters and assembling the filter at a preset position of a receiving module; the laser radar assembly method and the laser radar provided by the application can divide the emission wavelength range of an emission module into multiple small wavelength intervals through multiple filters, thereby reducing the bandwidth of the filters used, reducing the introduction of stray light and background light, and improving the ranging performance of the laser radar.

Description

Technical Field

[0001] This application relates to the field of laser detection, and more particularly to a lidar assembly method and a lidar. Background Technology

[0002] As an active ranging device, LiDAR typically includes a laser transmitting module and a receiving module. The transmitting module emits a laser beam towards the target object in the detection area, and the receiving module receives the laser beam emitted after it passes through the target object, obtaining parameters such as the target object's distance and velocity based on the reflected laser beam. The transmitting module includes a laser, which can be, for example, an LED (Light-Emitting Diode), an LD (Laser Diode), or a VCSEL (Vertical Cavity Surface Emitting Laser). Taking VCSEL as an example, due to manufacturing tolerances or temperature variations, the actual emission wavelength of the laser beam emitted by the VCSEL may deviate from the preset emission wavelength. This necessitates a larger bandwidth filter in the receiving module's processing of the reflected laser beam to meet the requirements. However, a larger bandwidth introduces more unwanted background light and other signal light, affecting the ranging performance of the LiDAR. Summary of the Invention

[0003] To address or partially address the problems existing in related technologies, this application provides a lidar assembly method and a lidar. By dividing the emission wavelength range of the emission module into multiple small wavelength intervals using multiple filters, the bandwidth of the filters used can be reduced, stray light and background light can be reduced, and the ranging performance of the lidar can be improved.

[0004] The first aspect of this application provides a method for assembling a lidar, the lidar including at least one transmitting module for emitting laser light into a detection area; and a receiving module for receiving echo laser light reflected from a target object in the detection area.

[0005] The assembly method includes:

[0006] Multiple filters are obtained, the combination of wavelength ranges allowed by the multiple filters covering the emission wavelength range; the emission wavelength range is the difference between the preset emission wavelength of the emitted laser and the wavelength offset range;

[0007] The actual emission wavelength of the emitted laser is detected;

[0008] A filter whose center wavelength matches the actual emission wavelength is selected from the multiple filters and assembled at a preset position in the receiving module.

[0009] In one specific implementation, the center wavelengths of the multiple filters are set at equal intervals, or the center wavelengths of the multiple filters are set according to the statistically obtained actual emission wavelength distribution of the emission module.

[0010] In one specific implementation, the multiple filters include multiple groups of filters, each group of filters including at least one filter; the center wavelengths of filters in the same group are equal, and the center wavelengths of filters in different groups are not equal; the number of filters included in each of the multiple groups of filters is positively correlated with the actual emission wavelength distribution of the emission module obtained according to statistics.

[0011] Furthermore, the lidar includes multiple transmitting modules; selecting a filter whose center wavelength matches the actual transmitting wavelength from among the multiple filters and assembling it at a preset position in the receiving module includes:

[0012] Multiple filters whose center wavelength matches the actual emission wavelength of the multiple transmitting modules are assembled at preset positions on the receiving module, so that the multiple filters respectively receive the echo laser reflected from the emitted laser of the multiple transmitting modules.

[0013] Furthermore, the lidar includes multiple transmitting modules; acquiring multiple filters includes: dividing each filter into multiple filtering regions, each filtering region being used to receive the echo laser reflected from the emitted laser of the multiple transmitting modules, and the combination of wavelength ranges allowed by the multiple filtering regions of the multiple filters covering the emission wavelength range;

[0014] The detection of the actual emission wavelength of the emitted laser includes: detecting the actual emission wavelength of the emitted laser from the plurality of emission modules;

[0015] The step of selecting a filter whose center wavelength matches the actual emission wavelength from the multiple filters and assembling it at a preset position in the receiving module includes: selecting multiple filter regions whose center wavelengths correspond one-to-one with the actual emission wavelengths of the emitted lasers from the multiple transmitting modules and assembling them at a preset position in the receiving module.

[0016] Furthermore, the emission field of view of two adjacent emission modules overlaps; an overlapping region is provided between two adjacent filter regions corresponding to the two adjacent emission modules, and the bandwidth of the overlapping region is greater than or equal to the bandwidth of the two adjacent filter regions, so as to cover the wavelength range allowed to pass through the two adjacent filter regions.

[0017] A second aspect of this application also provides a lidar, comprising:

[0018] At least one transmitting module is used to emit an outgoing laser toward the detection area;

[0019] A receiving module is used to receive the echo laser reflected by the target object in the detection area;

[0020] The receiving module uses a filter to filter the echo laser. The filter used to filter the echo laser is adjustable so that the center wavelength of the filter used to filter the echo laser matches the actual emission wavelength of the laser emitted by the transmitting module.

[0021] Optionally, the filter used to filter the echo laser is selected from a filter storage device that stores multiple filters; the combination of wavelength ranges allowed by the multiple filters covers the emission wavelength range; the filter used to filter the echo laser is set at a preset position in the receiving module.

[0022] Optionally, the lidar is internally provided with multiple filters, and the combination of wavelength ranges allowed by the multiple filters covers the emission wavelength range; the lidar is internally provided with a first adjustment structure, the first adjustment mechanism being used to adjust the filter whose center wavelength matches the actual emission wavelength to a preset position of the receiving module.

[0023] Optionally, the filter is provided with multiple filtering regions, and the combination of wavelength ranges allowed by the multiple filtering regions covers the emission wavelength range; the lidar is provided with a second adjustment mechanism, which is used to adjust the filtering region whose center wavelength matches the actual emission wavelength to a preset position of the receiving module.

[0024] In one specific implementation, when the filter used to filter the echo laser is selected from the filter storage device, the actual emission wavelength of the emitted laser from the emission module is detected by an external detection device.

[0025] In one specific implementation, when the lidar is equipped with multiple filters or the filters have multiple filtering regions, the lidar is equipped with a detection mechanism. The detection mechanism is used to detect the actual emission wavelength of the emitted laser from the emitting module. The first adjustment mechanism adjusts the filter whose center wavelength matches the actual emission wavelength to a preset position of the receiving module according to the detection result of the detection mechanism. Alternatively, the second adjustment mechanism adjusts the filtering region whose center wavelength matches the actual emission wavelength to a preset position of the receiving module according to the detection result of the detection mechanism.

[0026] A third aspect of this application also provides another type of lidar, including:

[0027] Multiple emission modules are used to emit laser beams into the detection area;

[0028] A receiving module is used to receive the echo laser reflected by the target object in the detection area;

[0029] The combined emission field of view of the plurality of transmitting modules is matched with the receiving field of view of the receiving module; the receiving module is provided with a plurality of filter units, which correspond one-to-one with the plurality of transmitting modules and are used to filter the echo laser after the emitted laser of the plurality of transmitting modules is reflected; the center wavelength of the wavelength range allowed to pass through each of the filter units is matched with the actual emission wavelength of the emitted laser of the corresponding transmitting module.

[0030] Furthermore, the emission fields of two adjacent emission modules overlap; an overlapping region is provided between two adjacent filter units corresponding to the two adjacent emission modules, and the bandwidth of the overlapping region is greater than or equal to the bandwidth of the two adjacent filter units, so as to cover the wavelength range allowed to pass through the two adjacent filter regions.

[0031] In a specific implementation, the plurality of filter units obtain the required center wavelength by coating different areas of the same substrate with filter material of the required thickness or type, or by attaching filter film of the required thickness. Alternatively, the plurality of filter units obtain the required center wavelength by coating multiple substrates with filter material of the required thickness or type, or by attaching filter film of the required thickness.

[0032] The technical solution provided in this application may include the following beneficial effects:

[0033] The lidar assembly method provided in this application divides the emission wavelength range of the transmitting module into multiple small wavelength intervals using multiple filters, thereby reducing the bandwidth of the filters used, reducing the introduction of stray light and background light, and improving the ranging performance of the lidar. Furthermore, the lidar provided in this application adjusts the center wavelength of the filter used to filter the echo laser so that the center wavelength of the filter used to filter the echo laser matches the actual emission wavelength of the transmitting module, thereby reducing the bandwidth of the filters used, reducing the introduction of stray light and background light, and improving the ranging performance of the lidar.

[0034] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit this application. Attached Figure Description

[0035] The exemplary embodiments of this application will be described in more detail with reference to the accompanying drawings, wherein the same reference numerals generally represent the same components in the exemplary embodiments of this application.

[0036] Figure 1 This is a simplified structural diagram illustrating the cooperation between the first type of receiving module and transmitting module in a lidar system, as shown in an embodiment of this application.

[0037] Figure 2 This is a flowchart illustrating the assembly method of a lidar according to an embodiment of this application;

[0038] Figure 3 This is a simplified structural diagram illustrating the cooperation between the second type of receiving module and transmitting module in a lidar system, as shown in an embodiment of this application.

[0039] Figure 4 This is a simplified structural diagram illustrating the cooperation between a third type of receiving module and a transmitting module in a lidar system, as shown in an embodiment of this application.

[0040] Figure 5 This is a simplified structural diagram of a filter set in a lidar according to an embodiment of this application;

[0041] Figure 6 This is a simplified schematic diagram of another structure of the filter provided in the lidar, as shown in the embodiments of this application;

[0042] Figure 7 This is a schematic diagram of another simplified structure of the filter provided in a lidar, as shown in an embodiment of this application;

[0043] Figure 8 This is a simplified structural diagram illustrating the cooperation between a fourth type of receiving module and a transmitting module in a lidar system, as shown in an embodiment of this application.

[0044] Figure 9 yes Figure 8 Another simplified structural diagram of the filter set in the image. Detailed Implementation

[0045] Embodiments of this application will now be described in more detail with reference to the accompanying drawings. While embodiments of this application are shown in the drawings, it should be understood that this application may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to make this application more thorough and complete, and to fully convey the scope of this application to those skilled in the art.

[0046] The terminology used in this application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The singular forms “a,” “the,” and “the” used in this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to and includes any or all possible combinations of one or more of the associated listed items.

[0047] It should be understood that although the terms "first," "second," "third," etc., may be used in this application to describe various information, this information should not be limited to these terms. These terms are only used to distinguish information of the same type from one another. For example, without departing from the scope of this application, first information may also be referred to as second information, and similarly, second information may also be referred to as first information. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0048] LiDAR, as an active ranging device, typically includes a laser transmitting module and a receiving module. The transmitting module emits a laser beam towards a target object in the detection area, and the receiving module receives the laser beam emitted after it passes through the target object. Based on the reflected laser beam, it obtains parameters such as the target object's distance and velocity. It can be widely used in industries with high precision requirements, such as autonomous driving and intelligent robots, without specific limitations here. The emitted laser beam from the transmitting module has a preset emission wavelength. However, in actual manufacturing and use, manufacturing tolerances and temperature variations can cause a deviation between the actual emission wavelength and the preset emission wavelength. This results in the emitted laser beam having a wavelength range, which is the difference between the preset emission wavelength and the wavelength deviation range. For example, the preset emission wavelength λ of the emitted laser beam from the transmitting module... 预 =905nm. Due to manufacturing tolerances, the wavelength shift of the emitting module is ±7nm. Accordingly, if only the wavelength shift caused by manufacturing tolerances is considered, the emission wavelength range of the emitted laser from the emitting module is 898nm~912nm (inclusive). The actual emission wavelength λ2 of the emitting module satisfies: 898nm≤λ 实 ≤912nm.

[0049] To receive laser light emitted from the transmitting module within its actual emission wavelength range, related technologies employ methods that increase the filter bandwidth. However, a wider filter bandwidth leads to more stray and background light being introduced into the detector of the receiving module, affecting the ranging performance of the lidar. To receive laser light emitted from the transmitting module within its actual emission wavelength range without increasing or even reducing the filter bandwidth, and to mitigate the impact of emission wavelength shifts caused by manufacturing tolerances and environmental temperature on lidar ranging performance, this application provides a lidar assembly method.

[0050] like Figure 1 As shown, in an exemplary scheme, the lidar includes a transmitting module 2 and a receiving module 1. The transmitting module 2 is used to transmit a laser beam to a target object in the detection area. The transmitted laser beam is reflected by the target object in the detection area, so that the laser beam carries target information and is fed back to the receiving module 1. The receiving module 1 processes the laser beam carrying the target information to obtain parameters such as the distance and speed of the target object.

[0051] Specifically, the transmitting module 2 includes a transmitting optical element 21 and a laser 22. The laser 22 is used to emit outgoing laser light. The transmitting optical element 21 is located on the light-emitting side of the laser 22 and is used to receive the outgoing laser light emitted by the laser 22 and direct the outgoing laser light toward the detection area. After being reflected by the target object in the detection area, the outgoing laser light forms an echo laser light carrying target information. The receiving module 1 is used to receive the echo laser light. The receiving module 1 includes a receiving optical element 11, a filter 12, and a detector 13. The receiving optical element 11 is used to receive the echo laser light. The filter 12 is located on the light-emitting side of the receiving optical element 11 and is used to filter the echo laser light received by the receiving optical element 11. The detector 13 is located on the light-emitting side of the filter 12 and is used to receive the filtered echo laser light light and convert the optical signal into an electrical signal. There is a preset position 101 between the receiving optical element 11 and the detector 13. The preset position 101 is used to place the filter 12.

[0052] like Figure 2 As shown, in one exemplary embodiment, the assembly method of a lidar includes the following steps:

[0053] Multiple filters 1211, 1212, ... 121N are obtained, and the combination of wavelength ranges allowed by the multiple filters 1211, 1212, ... 121N covers the emission wavelength range of the emission module 2;

[0054] Where N is a positive integer and N≥2; the emission wavelength range of emission module 2 is equal to the preset emission wavelength λ. 预 The difference between the wavelength offset range of the transmitting module 2 and the transmitting module 2;

[0055] Detecting the actual emission wavelength λ of the emitted laser 实 ;

[0056] Select the center wavelength and the actual emission wavelength λ from multiple filters 1211, 1212, ... 121N. 实 The matching filter 12 is assembled at the preset position 101 of the receiving module 1.

[0057] The working principle of the filter is briefly described below:

[0058] Filters all have a center wavelength and bandwidth. By setting the center wavelength and bandwidth of a filter, light within a certain wavelength range can be allowed to pass through while filtering out light of other wavelengths. For example, if a filter has a center wavelength of 905nm and a bandwidth of 1nm, then the filter allows light with wavelengths between 904.5nm and 905.5nm to pass through while filtering out light with wavelengths outside the range of 904.5nm to 905.5nm.

[0059] In one exemplary embodiment, the center wavelengths of the multiple filters 1211, 1212, ... 121N are designed according to the emission wavelength range of the emitted laser from the emitting module 2; the preset emission wavelength λ of the emitting module 2 is used. 预Taking a wavelength offset range of ±7nm as an example, the emission wavelength range of emission module 2 is 898nm to 912nm. If the emission wavelength range is divided into bands of 898nm, 899nm, ..., 911nm, 912nm at 1nm intervals, then the center wavelengths of multiple filters 1211, 1212, ..., 121N can be set at 1nm intervals. In this case, the number of multiple filters 1211, 1212, ..., 121N is N = 15, and the center wavelengths of the multiple filters 1211, 1212, ..., 121N are 898nm, 899nm, 900nm, 901nm, 902nm, 903nm, 904nm, 905nm, 906nm, 907nm, 908nm, 909nm, 910nm, and 912nm respectively. If the emission wavelength range is divided into bands of 898nm, 900nm, 902nm, 904nm, 906nm, 908nm, 910nm, and 912nm at 2nm intervals, then the center wavelengths of multiple filters 1211, 1212, ..., 121N can be set at 2nm intervals. In this case, the number of multiple filters 1211, 1212, ..., 121N is N=8, and the center wavelengths of the multiple filters 1211, 1212, ..., 121N are 898nm, 900nm, 902nm, 904nm, 906nm, 908nm, 910nm, and 912nm, respectively. Of course, the center wavelengths of multiple filters 1211, 1212, ..., 121N can also be set at other intervals.

[0060] The lidar assembly method provided in this application divides the emission wavelength range of the emitting module 2 into multiple small wavelength intervals using multiple filters 1211, 1212, ... 121N. The bandwidth of each filter 1211, 1212, ... 121N can be a small bandwidth; for example, the emission wavelength range of the emitting module 2 is 898nm to 912nm. The center wavelengths of the multiple filters 1211, 1212, ... 121N are 898nm, 899nm, 900nm, 901nm, 902nm, 903nm, 904nm, 905nm, 906nm, 907nm, 90 ... When the wavelengths are 8nm, 909nm, 910nm, 911nm, and 912nm, the bandwidth of multiple filters 1211, 1212, ... 121N can be set to 1nm, which can cover the emission wavelength range of 898nm to 912nm of the emission module 2. However, in related technologies, if only one filter is used to cover the emission wavelength range of 898nm to 912nm, the bandwidth of the filter is at least 14nm, which is much larger than the bandwidth of multiple filters 1211, 1212, ... 121N provided in this application embodiment. This will introduce more stray light and background light, affecting the ranging performance of the lidar.

[0061] The assembly method of the lidar provided in this application divides the emission wavelength range of the emission module 2 into multiple small wavelength intervals by using multiple filters 1211, 1212, ... 121N, thereby reducing the bandwidth of the filters used, reducing the introduction of stray light and background light, and improving the ranging performance of the lidar.

[0062] Specifically, the assembly method of the lidar provided in this application can use a detection device, such as a spectrometer, to detect the spectrum of the emitted laser emitted by the emitting module 2, thereby obtaining the actual emission wavelength λ of the emitted laser. 实 Then, based on the detection results of the detection device, the center wavelength and the actual emission wavelength λ are selected from multiple filters 1211, 1212, ... 121N. 实 The matching filter 12 is assembled at the preset position 101 of the receiving module 1.

[0063] In this embodiment, the center wavelength and the actual emission wavelength λ are selected from multiple filters 1211, 1212, ... 121N. 实 The matched filter 12 refers to the filter selected from multiple filters 1211, 1212, ... 121N, whose center wavelength is closest to the actual emission wavelength λ. 实 A filter, with the actual emission wavelength λ 实 The center wavelength of the matched filter 12 can be equal to the actual emission wavelength λ. 实 It can also be the closest to the actual emission wavelength λ. 实 The center wavelength. For example, the emission wavelength range of emission module 2 is 898nm~912nm; the center wavelengths of multiple filters 1211, 1212, ... 121N are 898nm, 899nm, 900nm, 901nm, 902nm, 903nm, 904nm, 905nm, 906nm, 907nm, 908nm, 909nm, 910nm, 911nm, 912nm, and 1nm, respectively. If the actual emission wavelength λ is detected by the detection device... 实 =905nm. At this point, a filter with a center wavelength of 905nm can be selected from multiple filters 1211, 1212, ... 121N and assembled at the preset position 101 of the receiving module 1; if the actual emission wavelength λ is detected by the detection device... 实 =905.8nm. At this time, a filter with a center wavelength of 906nm ​​can be selected from multiple filters 1211, 1212, ... 121N and assembled at the preset position 101 of the receiving module 1.

[0064] It is understandable that the number of multiple filters 1211, 1212, ... 121N is designed according to the actual emission wavelength offset relative to the preset emission wavelength, etc. Among them, the wavelength offset range of the laser in the emission module 2 caused by manufacturing tolerances can be obtained by those skilled in the art from the type of laser, manufacturing process, supplier and other relevant technical information; the wavelength offset range of the laser in the emission module 2 caused by changes in ambient temperature can be calculated by those skilled in the art based on the temperature drift coefficient of the laser and the operating temperature of the lidar, and this application does not limit this.

[0065] It is understandable that, due to the actual emission wavelength λ of the laser in emission module 2... 实 The emission wavelength range of the laser in the emission module 2 is affected by a variety of factors, such as manufacturing tolerances and temperature changes. Accordingly, the emission wavelength range of the laser is considered to be at least one of the wavelength shifts caused by various factors. For example, only the wavelength shift caused by manufacturing tolerances can be considered, or the wavelength drift caused by manufacturing tolerances and temperature changes can be considered at the same time. This application does not impose any restrictions on this.

[0066] It is understandable that in lidar, the wavelength shift caused by temperature changes is relatively small compared to the manufacturing tolerance of the laser. Therefore, in this application, the factors that cause the emission wavelength shift of the laser in the emission module 2 are mainly considered to be manufacturing tolerance.

[0067] Optionally, taking only the wavelength shift caused by manufacturing tolerances as an example, multiple filters 1211, 1212, ... 121N are obtained. The combination of wavelength ranges allowed by the multiple filters 1211, 1212, ... 121N to cover the emission wavelength range of the emission module 2 includes:

[0068] Obtain the preset emission wavelength and manufacturing tolerance range of the emission module 2;

[0069] Based on the preset emission wavelength and manufacturing tolerance range of the emission module 2, the emission wavelength range of the emission module 2 is obtained;

[0070] The emission wavelength range is divided by a preset interval to obtain multiple center wavelengths with the same interval.

[0071] Multiple center wavelengths are configured on multiple filters 1211, 1212, ... 121N.

[0072] In one exemplary embodiment, the center wavelengths of the multiple filters 1211, 1212, ... 121N are designed according to the emission wavelength range of the emitted laser from the emitting module 2; the preset emission wavelength λ of the emitting module 2 is used. 预Taking a wavelength offset range of ±7nm as an example, the emission wavelength range of emission module 2 is 898nm to 912nm. If the emission wavelength range is divided into bands of 898nm, 899nm, ..., 911nm, 912nm at 1nm intervals, then the center wavelengths of multiple filters 1211, 1212, ..., 121N can be set at 1nm intervals. In this case, the number of multiple filters 1211, 1212, ..., 121N is N = 15, and the center wavelengths of the multiple filters 1211, 1212, ..., 121N are 898nm, 899nm, 900nm, 901nm, 902nm, 903nm, 904nm, 905nm, 906nm, 907nm, 908nm, 909nm, 910nm, and 912nm respectively. If the emission wavelength range is divided into bands of 898nm, 900nm, 902nm, 904nm, 906nm, 908nm, 910nm, and 912nm at 2nm intervals, then the center wavelengths of multiple filters 1211, 1212, ..., 121N can be set at 2nm intervals. In this case, the number of multiple filters 1211, 1212, ..., 121N is N=8, and the center wavelengths of the multiple filters 1211, 1212, ..., 121N are 898nm, 900nm, 902nm, 904nm, 906nm, 908nm, 910nm, and 912nm, respectively. Of course, the center wavelengths of multiple filters 1211, 1212, ..., 121N can also be set at other intervals.

[0073] Optionally, the preset interval can also be 3nm, 4nm, etc. Depending on the preset interval, the number of filters can vary, such as 7 or 4 filters, as long as matching filters can be manufactured according to the band division scheme. This application does not impose specific limitations on this. Correspondingly, based on different band division schemes, the set bandwidth can be set to a relatively small bandwidth according to the preset interval to improve the ranging performance of the lidar.

[0074] Of course, depending on the type of laser used in the lidar, the preset emission wavelength λ 预 It's also possible that the emission wavelength range of the emitted laser will differ. Accordingly, multiple filters 1211, 1212, ... 121N are used according to the preset emission wavelength λ of the laser to be used. 预 The design can be based on the wavelength shift range of the laser, and this application does not limit the type of laser.

[0075] In this embodiment, the center wavelength of the filter can be changed by altering the thickness of the filter material, the type of filter material, the doping concentration of the filter material, or the number of filter film layers attached to the substrate. That is, multiple filters 1211, 1212, ... 121N can be obtained by designing the thickness of the filter material, the type of filter material, the doping concentration of the filter material, or the number of filter film layers attached to the substrate on multiple filters 1211, 1212, ... 121N.

[0076] In one exemplary scheme, the center wavelengths of multiple filters 1211, 1212, ... 121N are set at equal intervals, for example, 898nm, 899nm, 900nm, 901nm, 902nm, 903nm, 904nm, 905nm, 906nm, 907nm, 908nm, 909nm, 910nm, 911nm, 912nm, 898nm, 900nm, 902nm, 904nm, 906nm, 908nm, 910nm, 912nm.

[0077] In another exemplary scheme, the center wavelengths of the multiple filters 1211, 1212, ... 121N can be set according to the statistically obtained distribution of the actual emission wavelengths of the laser in the emission module 2.

[0078] Specifically, we can first count the actual emission wavelength λ of the lasers in the same batch of emission module 2. 实 The actual emission wavelength distribution of the lasers in the same batch of emission module 2 was statistically analyzed; then, based on the statistical results, multiple filters 1211, 1212, ... 121N were manufactured. For example, the statistically obtained actual emission wavelength λ of the laser... 实 The wavelengths are 904nm, 905nm, 906nm, 907nm, and 909nm. Based on the statistical results, multiple filters 1211, 1212, ..., 121N are designed with center wavelengths of 904nm, 905nm, 906nm, 907nm, and 909nm, respectively, and N = 4.

[0079] Understandably, due to advancements in modern manufacturing processes, for a large number of lasers, the actual emission wavelength of many lasers will be concentrated at a preset emission wavelength λ. 预 Accordingly, for the assembly of large batches of lidar, when multiple filters 1211, 1212, ... 121N are prepared in advance, the center wavelength is close to the preset emission wavelength λ. 预 The number of filters should be greater than the center wavelength and farther from the preset emission wavelength λ. 预 The number of filters; with a preset emission wavelength λ 预=905nm. Taking multiple filters 1211, 1212, ... 121N with center wavelengths of 898nm, 899nm, 900nm, 901nm, 902nm, 903nm, 904nm, 905nm, 906nm, 907nm, 908nm, 909nm, 910nm, 911nm, 912nm, and 898nm, 900nm, 902nm, 904nm, 906nm, 908nm, 910nm, and 912nm as an example, the number of filters with a center wavelength of 905nm is greater than the number of filters with a center wavelength of 898nm.

[0080] Specifically, the multiple filters 1211, 1212, ... 121N comprise multiple groups of filters, each group comprising at least one filter; filters within the same group have equal center wavelengths, while filters in different groups have unequal center wavelengths; the number of filters in each group corresponds to the actual emission wavelength λ of the emission module 2 obtained statistically. 实 The distributions are positively correlated; among them, the statistically obtained actual emission wavelength λ 实 The more lasers there are, the more filters are needed to match those lasers.

[0081] In another exemplary embodiment, the lidar includes multiple transmitting modules 2, where multiple means two or more ( Figure 3 Taking two transmitting modules 2 as an example); in the assembly method of the lidar, the center wavelength and the actual transmission wavelength λ are selected from multiple filters 1211, 1212, ... 121N. 实 The matching filter 12 is assembled at a preset position 101 of the receiving module 1, including:

[0082] Among multiple filters 1211, 1212, ... 121N, a center wavelength is selected that corresponds to the actual emission wavelength λ of each of the multiple emission modules. 实 Multiple matching filters 12 are assembled at preset positions in the receiving module 1 so that the multiple filters receive the echo lasers reflected from the emitted lasers of the multiple transmitting modules and perform filtering processing on the echo lasers reflected from the emitted lasers of the multiple transmitting modules.

[0083] like Figure 3 As shown, taking two transmitting modules 2 as an example, the two transmitting modules 2 are referred to as the first transmitting module 2A and the second transmitting module 2B, respectively. The first transmitting module 2A and the second transmitting module 2B are respectively arranged on both sides of the receiving module 1 along the first direction X. The filter 12 located at the preset position 101 includes at least a first filter 12a and a second filter 12b arranged along the first direction X. The center wavelength of the first filter 12a is the same as the actual emission wavelength λ of the second transmitting module 2B. 实BThe center wavelength of the second filter 12b is matched with the emission wavelength of the first emission module 2A.

[0084] By arranging a first transmitting module 2A and a second transmitting module 2B on both sides of the receiving module 1 in the first direction X, the detection field of view is increased, improving detection capability and accuracy. In this configuration, to ensure that the laser beams emitted by the two transmitting modules 2 can enter the receiving module 1 after emission and are simultaneously filtered by the filter 12 at the preset position 101, the filter 12 at the preset position 101 includes at least a first filter 12a and a second filter 12b arranged along the first direction X. The center wavelength and layout range of the first filter 12a correspond to the actual emission wavelength λ of the second laser 22B located in the second transmitting module 2B. 实B Matching the emission field of view, the center wavelength and layout range of the second filter 12b are consistent with the actual emission wavelength λ of the first laser 22A set in the first emission module 2A. 实A Matching the launch field of view.

[0085] In another exemplary embodiment, the lidar includes multiple transmitting modules 2, where multiple means two or more; in the lidar assembly method,

[0086] Multiple filters 1211, 1212, ... 121N are obtained. The combination of wavelength ranges allowed by multiple filters 1211, 1212, ... 121N covers the emission wavelength range of emission module 2, including:

[0087] Each of the multiple filters 1211, 1212, ... 121N is divided into multiple filtering regions that correspond one-to-one with the multiple transmitting modules 2. The multiple filtering regions are used to receive the echo laser reflected from the emitted laser of the multiple transmitting modules 2. The combination of the wavelength ranges allowed to pass through the multiple filtering regions of the multiple filters 1211, 1212, ... 121N covers the emission wavelength range.

[0088] Detecting the actual emission wavelength λ of the emitted laser 实 Includes: detecting the actual emission wavelength λ of the emitted laser from multiple emission modules 2. 实 ;

[0089] Select the center wavelength and the actual emission wavelength λ from multiple filters 1211, 1212, ... 121N. 实 The matching filter 12 is assembled at a preset position 101 of the receiving module 1, which includes: selecting the center wavelength of multiple filtering regions from multiple filters 1211, 1212, ... 121N and matching them with the actual emission wavelength λ of the emitted laser from multiple transmitting modules 2. 实The corresponding filters are assembled at the preset position 101 of the receiving module 1.

[0090] like Figure 4 As shown, taking two transmitting modules 2 as an example, the two transmitting modules 2 are denoted as the first transmitting module 2A and the second transmitting module 2B, respectively. The first transmitting module 2A and the second transmitting module 2B are respectively arranged on both sides of the receiving module 1 along the first direction X; as shown Figure 4 As shown, the filter 12 located at the preset position 101 includes at least a first filtering region 121 (which may correspond to the region where the first filter 12a is located) and a second filtering region 122 (which may correspond to the region where the second filter 12b is located) arranged along the first direction X. The center wavelength of the first filtering region 121 is the same as the actual emission wavelength λ of the second emission module 2B. 实B The center wavelength of the second region 122 is matched with the emission wavelength of the first transmitting module 2A.

[0091] Optionally, the center wavelength and layout range of the first filtering region 121 are respectively related to the actual emission wavelength λ of the second laser 22B set in the second emission module 2B. 实B Matching the emission field of view, the center wavelength and layout range of the second filter region 122 are the same as the actual emission wavelength λ of the first laser 22A set in the first emission module 2A. 实A Matching the launch field of view.

[0092] Optionally, in another exemplary embodiment, the emission field of view portions of two adjacent emission modules 2 overlap; correspondingly, an overlapping region 125 is provided between two adjacent filter regions corresponding to two adjacent emission modules 2 (e.g., Figure 5 As shown), the bandwidth of the overlapping region 125 is greater than or equal to the bandwidth of the two adjacent filter regions, so as to cover the wavelength range that the two adjacent filter regions are allowed to pass through.

[0093] Specifically, when the emission field of view of two adjacent emission modules 2 overlap, the area connected between the first filter region 121 and the second filter region 122 located at the preset position 101 may simultaneously receive the emitted laser from the first emission module 2A and the emitted laser from the second emission module 2B. This area, which simultaneously receives the emitted laser from the first emission module 2A and the emitted laser from the second emission module 2B, is denoted as the overlapping region 125. The size of the overlapping region 125 is positively correlated with the overlapping field of view of the first emission module 2A and the second emission module 2B; that is, the larger the overlapping field of view of the first emission module 2A and the second emission module 2B, the larger the overlapping region 125 on the filter. The bandwidth of the overlapping region 125 is greater than or equal to the bandwidth of the first filter region 121 and the second filter region 122, so as to cover the wavelength range allowed to pass through the first filter region 121 and the second filter region 122, enabling the overlapping region 125 to perform better filtering processing on two or more echo lasers. The size of the overlapping region 125 can be adjusted according to the specific situation of the overlapping field of view, and no specific limit is made here.

[0094] Specifically, when the center wavelength and bandwidth of the first filter region 121 and the second filter region 122 are equal, the center wavelength and bandwidth of the overlapping region 125 can be set to be equal to the center wavelength and bandwidth of the first filter region 121 and the second filter region 122; when the center wavelengths of the first filter region 121 and the second filter region 122 are not equal, the bandwidth of the overlapping region 125 needs to be set to be greater than the bandwidth of the first filter region 121 and the second filter region 122, so as to cover the wavelength range that the first filter region 121 and the second filter region 122 are allowed to pass through.

[0095] Optionally, if there is no region on filter 12 that receives echo lasers of two or more emission wavelengths simultaneously, an intermediate region can be provided between the first filtering region 121 and the second filtering region 122 of filter 12. This intermediate region separates the first region 123 and the second region 123. When multiple lasers 22 are provided in a single emission module 2, it can also be used to separate adjacent filtering regions. By providing this intermediate region, the regions used to receive echo lasers of different emission wavelengths are spaced apart, avoiding the problem of poor filtering at the boundary lines between different regions.

[0096] In an optional embodiment, when a first transmitting module 2A and a second transmitting module 2B are provided in the lidar, the filter 12 located at the preset position 101 can be an integral filter 12. Corresponding areas on the filter 12 are coated with filter materials of different thicknesses to form first filtering regions 121, second filtering regions 122, overlapping regions 125, etc., with different center wavelengths. Alternatively, the filter 12 at the preset position 101 can include a detachably connected first filter and second filter, with the first filtering region 121 located on the first filter and the second filtering region 122 located on the second filter. The desired structure is formed by combining filters with different center wavelengths. The detachable connection of the filter 12 can be, for example, bonding or welding, and is not specifically limited here.

[0097] Secondly, this application also provides a lidar that can receive the emitted laser with the actual emission wavelength of the transmitting module within a certain emission wavelength range without increasing or even reducing the bandwidth of the filter, thereby reducing the impact of emission wavelength shift caused by manufacturing tolerances and ambient temperature on the lidar ranging performance.

[0098] Specifically, the lidar includes: at least one transmitting module 2 for emitting laser light into a detection area; and a receiving module 1 for receiving echo laser light reflected from a target object in the detection area. The receiving module 1 uses a filter 12 to filter the echo laser light, wherein the filter 12 is adjustable so that the center wavelength of the filter 12 is equal to the actual emission wavelength λ of the laser light emitted by the transmitting module 2. 实 match.

[0099] In one exemplary embodiment, the transmitting module 2 includes a transmitting optical element 21 and a laser 22. The laser 22 emits an outgoing laser beam. The transmitting optical element 21 is located on the light-emitting side of the laser 22 and is used to receive the outgoing laser beam emitted by the laser 22 and direct the outgoing laser beam toward a detection area. After being reflected by a target object within the detection area, the outgoing laser beam forms an echo laser beam carrying target information. The receiving module 1 is used to receive the echo laser beam. The receiving module 1 includes a receiving optical element 11, a filter 12, and a detector 13. The receiving optical element 11 is used to receive the echo laser beam, and the filter 12... Located on the light-emitting side of the receiving optical element 11, the detector 13 is located on the light-emitting side of the filter 12 and is used to filter the echo laser received by the receiving optical element 11. The detector 13 is located on the light-emitting side of the filter 12 and is used to receive the filtered echo laser and convert the optical signal into an electrical signal. A preset position 101 is provided between the receiving optical element 11 and the detector 13 for placing the filter 12. The filter 12 for filtering the echo laser is adjustable so that its center wavelength is aligned with the actual emission wavelength λ of the emitted laser from the transmitting module 2. 实 match.

[0100] In one exemplary embodiment, the filter 12 used for filtering the echo laser is selected from a filter storage device (not shown) that stores multiple filters 1211, 1212, ... 121N; the center wavelengths of the multiple filters 1211, 1212, ... 121N are set according to the emission wavelength range of the emitted laser of the transmitting module 2, and the combination of wavelength ranges allowed by the multiple filters 1211, 1212, ... 121N covers the emission wavelength range of the emitted laser of the transmitting module 2 (the center wavelength setting method of the multiple filters is the same as the design method of the center wavelength of the multiple filters in the above assembly method, and will not be repeated here); the filter used for filtering the echo laser is set at a preset position 101 of the receiving module 1.

[0101] Specifically, filters can be selected manually from the filter storage device, using tools, or automatically by automated equipment, such as a robot, from multiple filters 1211, 1212, ... 121N in the filter storage device to select the center wavelength and the actual emission wavelength λ. 实 The matching filter 12 is set at the preset position 101 of the receiving module 1.

[0102] Specifically, the automated equipment may include a filter pickup module and a motion module. The motion module can drive the filter pickup module to move, so that the filter pickup module picks up the center wavelength and the actual emission wavelength λ from the filter storage device. 实 Match the filter 12 and move the filter 12 to the preset position 101.

[0103] Optionally, the lidar uses an external detection device, such as an external spectrometer, to detect the actual emission wavelength λ of the emitted laser from the emission module 2. 实 .

[0104] Furthermore, the control module in the automated equipment is electrically connected to an external detection device. Based on the detection results from the external detection device, it controls the motion module to drive the filter pickup module to move, so that the filter pickup module picks up the center wavelength and the actual emitted wavelength λ from the filter storage device. 实 Match the filter 12 and move the filter 12 to the preset position 101.

[0105] In another exemplary embodiment, multiple filters 1211, 1212, ... 121N are disposed inside the lidar. The center wavelengths of the multiple filters 1211, 1212, ... 121N are set according to the emission wavelength range of the emitted laser from the emitting module. The combination of wavelength ranges allowed by the multiple filters 1211, 1212, ... 121N covers the emission wavelength range of the emitted laser from the emitting module 2 (the method of setting the center wavelengths of the multiple filters is the same as the design method of the center wavelengths of the multiple filters in the above assembly method, and will not be repeated here). The lidar is provided with a first adjustment structure (not shown), which is used to adjust the center wavelength to match the actual emission wavelength λ of the emitted laser from the emitting module 2. 实 The matching filter is adjusted to the preset position 101 of the receiving module 1.

[0106] In this embodiment, the first adjustment mechanism adjusts the movement of multiple filters 1211, 1212, ... 121N so that the lidar can adjust the movement according to the actual emission wavelength λ of the transmitting module 2. 实 The center wavelength is compared with the actual transmitted wavelength λ. 实 The matched filter 12 is adjusted to the preset position 101 of the receiving module 1; however, the center wavelength is not aligned with the actual transmission wavelength λ. 实 The other matching filters are transported by the first adjustment mechanism to a space inside the laser that is not involved in laser transmission and reception, so as not to affect the laser radar's laser transmission and reception.

[0107] In one exemplary embodiment, a first adjustment mechanism is located below the transmitting module 2 and the receiving module 1. The first adjustment mechanism includes a mounting frame (not shown), a transmission module (not shown), and a driving module (not shown). The mounting frame is used to assemble multiple filters 1211, 1212, ... 121N. The transmission module moves under the drive of the driving module, causing the mounting frame to move, thereby aligning the center wavelength with the actual transmitted wavelength λ. 实 The matched filter 12 is adjusted to the preset position 101 of the receiving module 1, and the remaining center wavelengths are not aligned with the actual transmission wavelength λ.实 The matching filter is then transported by the transmission mechanism to a space inside the laser that does not involve laser transmission and reception.

[0108] Furthermore, the first adjustment mechanism also includes multiple liftable support units (not shown) corresponding one-to-one with the multiple filters 1211, 1212, ... 121N. The multiple filters 1211, 1212, ... 121N are mounted on the mounting frame via the multiple liftable support units. The transmission module moves under the drive of the drive module, which in turn moves the mounting frame to align the center wavelength with the actual emission wavelength λ. 实 The matching filter 12 is adjusted to a position below the preset position 101 of the receiving module 1, and then the corresponding liftable support unit lifts the filter 12 to the preset position 101.

[0109] Furthermore, the lidar may also include a detection mechanism (not shown), which can be a spectrometer used to detect the spectrum of the emitted laser from the transmitting module 2, thereby obtaining the actual emission wavelength λ of the emitted laser. 实 The first adjustment mechanism is electrically connected to the detection mechanism. Based on the detection results of the detection mechanism, the center wavelengths of multiple filters 1211, 1212, ... 121N are adjusted to match the actual emission wavelength λ. 实 The matching filter 12 is adjusted to the preset position 101 of the receiving module 1.

[0110] like Figure 6 As shown in Figure 7, in another exemplary scheme, the filter 12 is provided with multiple filter regions 1221, 1222, ... 122N. The center wavelengths of the multiple filter regions 1221, 1222, ... 122N are set according to the emission wavelength range of the emitted laser of the emitting module 2. The combination of wavelength ranges allowed by the multiple filter regions 1221, 1222, ... 122N covers the emission wavelength range of the emitted laser of the emitting module 2 (the center wavelength setting method of the multiple filter regions is the same as the design method of the center wavelengths of the multiple filters 1211, 1212, ... 121N in the above assembly method, and will not be repeated here). The lidar is provided with a second adjustment mechanism (not shown), which is used to adjust the center wavelength with the actual emission wavelength λ. 实 The matching filter area is adjusted to the preset position 101 of the receiving module 1.

[0111] It is understandable that the number of multiple filter regions 1221, 1222, ... 122N can be 2, 3, 4, 5, 6, etc., and can be adaptively adjusted according to the emission wavelength range of the emission module 2. Furthermore, the division of the multiple filter regions 1221, 1222, ... 122N of the filter 12 can also include other types of division, such as a rotating structure (e.g., Figure 7The desired area can be adjusted to a preset position 101 by moving or rotating the filter 12, but this application does not make any specific limitation on this.

[0112] In one exemplary embodiment, the second adjustment mechanism includes a gripper (not shown) and a motion module (not shown). The gripper holds the filter 12 in place, and the motion module controls the movement of the gripper to align the center wavelength on the filter 12 with the actual emitted wavelength λ. 实 The matched filter area is adjusted to the preset position 101 of the receiving module 1, and the remaining center wavelengths are not matched with the actual transmission wavelength λ. 实 The matching filter is then transported by the transmission mechanism to a space inside the laser that does not involve laser transmission and reception.

[0113] Furthermore, the lidar may also include a detection mechanism, which can employ a spectrometer to detect the spectrum of the emitted laser from the transmitting module 2, thereby obtaining the actual emission wavelength λ of the emitted laser. 实 The second adjustment mechanism is electrically connected to the detection mechanism. Based on the detection results of the detection mechanism, it adjusts the center wavelength on filter 12 to match the actual emission wavelength λ. 实 The matching filter area is adjusted to the preset position 101 of the receiving module 1.

[0114] It is understood that various mechanical structures can be used to coordinate the specific structures of the first adjustment mechanism, the second adjustment mechanism, the transmission module and drive module, the filter pickup module and motion module, and the detection mechanism used in the automated equipment, and this application does not impose any restrictions on this.

[0115] Optionally, when adjusting one filter 12 to locally position 101 or adjusting multiple filters 12 to position a filter 12 that meets the conditions, the emission wavelength of the laser beam emitted by the transmitting module 2 can be detected before the laser radar assembly is completed. This allows for manual adjustment of the corresponding filter 12 or a localized portion of the filter 12 to the preset position 101, thereby achieving the actual emission wavelength λ. 实 Matching with the center wavelength. Alternatively, auxiliary components within the lidar can be used to drive the filter 12 to perform the corresponding actions; no specific limitations are specified here.

[0116] When the filter 12 is driven to perform corresponding actions by setting auxiliary components, the lidar includes a first adjustment mechanism or a second adjustment mechanism. The first adjustment mechanism or the second adjustment mechanism can drive the filter 12 to move, so that the filter 12 is aligned with the actual emission wavelength λ. 实 The matched area is moved to a preset position 101, or the center wavelength of the multiple filters 12 is aligned with the actual emission wavelength λ. 实 The matched filter 12 moves to the preset position 101.

[0117] Optionally, when the filter 12 is divided into multiple filtering regions along the circumferential direction, a turntable-like structure is formed, and the second adjustment mechanism is used to adjust the rotation of the filter 12. This is done to obtain the desired wavelength λ. 实 After matching the value of the center wavelength, the lidar controls the movement of the second adjustment mechanism to rotate the area where the corresponding center wavelength is located to the preset position 101, while other areas are outside the preset position.

[0118] Optionally, when the filter 12 is divided into multiple regions 121 along a certain direction (such as the first direction Y or the first direction X), the second adjustment mechanism can drive the filter 12 to reciprocate in the corresponding direction so that the region containing the center wavelength that meets the conditions is located at a preset position 101, and other regions are located outside the preset position 101. Alternatively, in addition to the above-described division method of the regions in the filter 12, other division methods can also be used, and this application does not specifically limit them.

[0119] It is understandable that the movement of a filter 12 is adjusted by the second adjustment mechanism to make the center wavelength align with the actual emission wavelength λ. 实 In the matching scheme, depending on the specific design of the transmitting module 2, when there are two or more transmitting modules 2, that is, the actual transmitted wavelength λ of the echo laser received by the receiving module 1. 实 When there are two or more, there are also a corresponding number of matching center wavelengths. The arrangement of the center wavelength values ​​pre-set in the filter 12 can be adaptively adjusted in advance according to the actual situation, so that the center wavelengths of multiple adjacent regions can exactly match multiple actual emission wavelengths λ. 实 One-to-one matching, and all the matched center wavelengths are in the preset position.

[0120] It is understandable that the first adjustment mechanism and the second adjustment mechanism can select the appropriate driving method according to different situations such as the different division forms of multiple filter areas in a filter 12, and whether it is necessary to drive the movement of one filter 12 or multiple filters 12. Under different circumstances, the specific structure of the adjustment mechanism will also be different, and no specific limitation is made here.

[0121] Thirdly, this application also provides another type of lidar that can receive the emitted lasers from multiple transmitting modules within a single emission wavelength range without increasing or even reducing the bandwidth of the filter, thereby reducing the impact of emission wavelength shifts caused by manufacturing tolerances and ambient temperature on the lidar ranging performance.

[0122] Specifically, lidar includes:

[0123] Multiple emission modules 2 are used to emit laser beams toward the detection area;

[0124] Receiver module 1 is used to receive the echo laser reflected by the target object in the detection area;

[0125] The combined emission field of view of multiple transmitting modules 2 is matched with the receiving field of view of receiving module 1; receiving module 1 is provided with multiple filter units, each corresponding one-to-one with multiple transmitting modules 2, used to filter the echo laser after reflection from the emitted laser of multiple transmitting modules 1; the center wavelength of the wavelength range allowed to pass through each filter unit corresponds to the actual emission wavelength λ of the emitted laser of the corresponding transmitting module 2. 实 match.

[0126] Taking two transmitting modules 2 as an example, denoted as the first transmitting module 2A and the second transmitting module 2B respectively; in an exemplary scheme, the first transmitting module 2A and the second transmitting module 2B are respectively disposed on both sides of the receiving module 1 along the first direction X, and multiple filtering units are a first filtering region 121 and a second filtering region 122 disposed on the same filter along the first direction X, wherein the center wavelength of the first filtering region 121 is the same as the actual emission wavelength λ of the second transmitting module 2B. 实B The center wavelength of the second region 122 is matched with the emission wavelength of the first transmitting module 2A.

[0127] By arranging a first transmitting module 2A and a second transmitting module 2B on both sides of the receiving module 1 along the first direction X, the detection field of view is increased, improving detection capability and accuracy. In this configuration, to ensure that the laser beams emitted by the two transmitting modules 2 can enter the receiving module 1 after emission and are simultaneously filtered by the filter 12 at the preset position 101, a first filtering region 121 and a second filtering region 122 are arranged on the filter along the first direction X. The center wavelength and layout range of the first filtering region 121 correspond to the actual emission wavelength λ of the second laser 22B located in the second transmitting module 2B. 实B Matching the emission field of view, the center wavelength and layout range of the second filter region 122 are the same as the actual emission wavelength λ of the first laser 22A set in the first emission module 2A. 实A Matching the launch field of view.

[0128] See Figure 8 As shown, the first transmitting module 2A has a first transmitting field of view a1, the second transmitting module 2B has a second transmitting field of view a2, and the receiving module 1 has a receiving field of view a3. The combination of the first transmitting field of view a1 and the second transmitting field of view a2 matches the receiving field of view a3. Taking a horizontal transmitting field of view of 60° for the first transmitting module 2A and a horizontal transmitting field of view of 60° for the second transmitting module 2B as an example, a detailed explanation will be provided.

[0129] The first laser 22A is located on the incident side of the first emitting optical element 21A, closer to the receiving module 1. The first emitting optical element 21A forms a first emission field of view a1 at a 60-degree angle away from the receiving module 1. The second laser 22B is located on the incident side of the second emitting optical element 21B, closer to the receiving module 1. The second emitting optical element 21B forms a second emission field of view a2 at a 60-degree angle away from the receiving module 1. Based on the first emission field of view a1 and the second emission field of view a2, when the receiving field of view a3 is exactly equal to the sum of the first emission field of view a1 and the second emission field of view a2 (see... Figure 8 When the echo laser is emitted into the filter 12 by the receiving optical element 11 (i.e., at 120°), in order to match the center wavelength of the filter 12 with the emission wavelengths of the first and second emission modules 2A and 2B, a first filtering region 121 and a second filtering region 122 are provided on the filter along the first direction X. The center wavelength of the first filtering region 121 is the same as the actual emission wavelength λ of the second laser 22B provided in the second emission module 2B. 实B Matching, the center wavelength of the second filter region 122 is matched with the actual emission wavelength λ of the first laser 22A set in the first emission module 2A. 实A match.

[0130] It is understandable that the size of the first region 123 and the second region 124 in the filter 12 needs to be adjusted according to the actual cooperation between the transmitting module 2 and the receiving module 1, and no specific limitation is made here.

[0131] In another exemplary scheme, the emission field of view of two adjacent emission modules 2 in the plurality of emission modules 2 overlap (see [reference]). Figure 4 Correspondingly, an overlapping region 125 is provided between two adjacent filter regions corresponding to two adjacent emission modules 2. The bandwidth of the overlapping region 125 is greater than or equal to the bandwidth of the two adjacent filter regions, so as to cover the wavelength range that the two adjacent filter regions are allowed to pass through.

[0132] Specifically, when the emission field of view of two adjacent emission modules 2 overlap, the area connected between the first filter region 121 and the second filter region 122 located at the preset position 101 may simultaneously receive the emitted laser from the first emission module 2A and the emitted laser from the second emission module 2B. This area, which simultaneously receives the emitted laser from the first emission module 2A and the emitted laser from the second emission module 2B, is denoted as the overlapping region 125. The size of the overlapping region 125 is positively correlated with the overlapping field of view of the first emission module 2A and the second emission module 2B; that is, the larger the overlapping field of view of the first emission module 2A and the second emission module 2B, the larger the overlapping region 125 on the filter. The bandwidth of the overlapping region 125 is greater than or equal to the bandwidth of the first filter region 121 and the second filter region 122, so as to cover the wavelength range allowed to pass through the first filter region 121 and the second filter region 122, enabling the overlapping region 125 to perform better filtering processing on two or more echo lasers. The size of the overlapping region 125 can be adjusted according to the specific circumstances of the overlapping field of view; this application does not impose specific limitations on it.

[0133] Specifically, when the center wavelength and bandwidth of the first filter region 121 and the second filter region 122 are equal, the center wavelength and bandwidth of the overlapping region 125 can be set to be equal to the center wavelength and bandwidth of the first filter region 121 and the second filter region 122; when the center wavelengths of the first filter region 121 and the second filter region 122 are not equal, the bandwidth of the overlapping region 125 needs to be set to be greater than the bandwidth of the first filter region 121 and the second filter region 122, so as to cover the wavelength range that the first filter region 121 and the second filter region 122 are allowed to pass through.

[0134] Optionally, if there is no region on filter 12 that receives echo lasers of two or more emission wavelengths simultaneously, an intermediate region can be provided between the first filtering region 121 and the second filtering region 122 of filter 12. This intermediate region separates the first region 123 and the second region 123. When multiple lasers 22 are provided in a single emission module 2, it can also be used to separate adjacent filtering regions. By providing this intermediate region, the regions used to receive echo lasers of different emission wavelengths are spaced apart, avoiding the problem of poor filtering at the boundary lines between different regions.

[0135] In another exemplary embodiment, a plurality of first lasers 22A are disposed on the first transmitting module 2A along the second direction Y, and a plurality of second lasers 22B are disposed on the second transmitting module 2A along the second direction Y; the first filtering region 121 is divided into a plurality of first sub-filtering regions along the second direction Y, and the second filtering region 122 is divided into a plurality of second sub-filtering regions along the second direction Y; the number, center wavelength, and layout of the plurality of first sub-filtering regions in the first filtering region 121 match the number, actual emission wavelength, and layout of the plurality of second lasers disposed in the second transmitting module 2B; the number, center wavelength, and layout of the plurality of second sub-filtering regions in the second filtering region 122 match the number, actual emission wavelength, and layout of the plurality of first lasers disposed in the first transmitting module 2A.

[0136] like Figure 9 As shown, taking two first lasers 221A and 222A arranged along the second direction Y on the first transmitting module 2A, and two second lasers 221B and 222B arranged along the second direction Y on the second transmitting module 2A as an example; in an exemplary scheme, multiple filtering units include a first filtering region 121 and a second filtering region 122 arranged along the first direction X. The first filtering region 121 includes two first sub-filtering regions 1211 and 1212 arranged along the second direction Y, and the second filtering region 122 includes two second sub-filtering regions 1221 and 1222 arranged along the second direction; wherein, the center wavelengths of the two first sub-filtering regions 1211 and 1212 are respectively the actual emission wavelengths λ of the two second lasers 221B and 222B of the second transmitting module 2B. 实B1 , λ 实B2 Matching, the center wavelengths of the two second sub-filter regions 1221 and 1222 are respectively matched with the actual emission wavelengths λ of the two first lasers 221A and 222A of the first emission module 2A. 实A1 , λ 实A2 match.

[0137] When the emission field of view of two adjacent lasers in multiple emission modules 2 overlaps; correspondingly, as... Figure 9 As shown, an overlapping region 125 is provided between two adjacent sub-filter regions corresponding to two adjacent lasers. The bandwidth of the overlapping region 125 is greater than or equal to the bandwidth of the two adjacent sub-filter regions, so as to cover the wavelength range that the two adjacent sub-filter regions are allowed to pass through.

[0138] Specifically, when the emission field of view of two adjacent lasers in multiple emission modules 2 overlap, the two adjacent sub-filter regions corresponding to the two adjacent lasers may simultaneously receive the emitted lasers from the two adjacent lasers. This region that simultaneously receives the emitted lasers from the two adjacent lasers is denoted as the overlapping region 125. The size of the overlapping region 125 is positively correlated with the overlapping field of view of the two adjacent lasers; that is, the larger the overlapping field of view of the two adjacent lasers, the larger the overlapping region 125 on the filter. The bandwidth of the overlapping region 125 is greater than or equal to the bandwidth of the two adjacent sub-filter regions corresponding to the two adjacent lasers, so as to cover the wavelength range allowed to pass through the two adjacent sub-filter regions, enabling the overlapping region 125 to perform better filtering of two or more echo lasers. The size of the overlapping region 125 can be adjusted according to the specific situation of the overlapping field of view; this application does not impose any restrictions on this.

[0139] Specifically, when the center wavelength and bandwidth of the two adjacent sub-filter regions corresponding to the two adjacent lasers are equal, the center wavelength and bandwidth of the overlapping region 125 can be set to be equal to the center wavelength and bandwidth of the two adjacent sub-filter regions corresponding to the two adjacent lasers; when the center wavelengths of the two adjacent sub-filter regions corresponding to the two adjacent lasers are not equal, the bandwidth of the overlapping region 125 needs to be set to be greater than the bandwidth of the two adjacent sub-filter regions corresponding to the two adjacent lasers, so as to cover the wavelength range allowed to pass through the two adjacent sub-filter regions corresponding to the two adjacent lasers.

[0140] Optionally, if there is no region on filter 12 that receives echo lasers of two or more emission wavelengths simultaneously, an intermediate region can be provided between two adjacent sub-filter regions of filter 12. This intermediate region separates the two adjacent sub-filter regions. When multiple lasers 22 are provided in a single emission module 2, this intermediate region can also be used to separate two adjacent sub-filter regions. By providing an intermediate region, the regions used to receive echo lasers of different emission wavelengths are arranged at intervals, avoiding the problem of poor filtering effect at the boundary lines between different regions.

[0141] Optionally, multiple filter units can obtain the required center wavelength by coating different areas of the same substrate with filter material of the required thickness or the required type of filter material, or by attaching a filter film of the required thickness.

[0142] Optionally, multiple filter units can obtain the required center wavelength by coating multiple substrates with filter material of the required thickness or type, or by attaching filter film of the required thickness.

[0143] Furthermore, the lidar provided in the above embodiment uses a filter 12 with a temperature drift coefficient consistent with that of the laser in the transmitting module 2, so as to improve the consistency between the actual emission wavelength of the emitted laser emitted by the transmitting module 2 and the wavelength shift allowed by the filter 12, thereby reducing the impact of temperature drift on the wavelength shift of the emitted laser on the laser ranging performance.

[0144] Furthermore, the lidar provided in the above embodiments also includes a thermal circulation mechanism. For example, a heat conduction device is provided between the transmitting plate of the transmitting module and the receiving plate of the receiving module to reduce the temperature difference between the transmitting module and the receiving module, thereby reducing the impact of wavelength shift of the emitted laser caused by temperature drift on the laser ranging performance.

[0145] The various embodiments of this application have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen to best explain the principles, practical application, or improvement of the technology in the market, or to enable others skilled in the art to understand the embodiments disclosed herein.

Claims

1. A method of assembling a lidar, characterized by, The lidar includes at least one transmitting module for emitting laser light into the detection area; and a receiving module for receiving the echo laser light reflected from a target object in the detection area. The assembly method includes: Multiple filters are obtained, the combination of wavelength ranges allowed by the multiple filters covering the emission wavelength range; the emission wavelength range is the difference between the preset emission wavelength of the emitted laser and the wavelength offset range, the wavelength offset range being caused by laser manufacturing tolerances and / or temperature variations, and all multiple filters employing narrow bandwidths; The actual emission wavelength of the emitted laser is detected; A filter whose center wavelength matches the actual emission wavelength is selected from the multiple filters and assembled at a preset position in the receiving module.

2. The assembly method according to claim 1, characterized in that, The center wavelengths of the multiple filters are set at equal intervals, or the center wavelengths of the multiple filters are set according to the statistically obtained distribution of the actual emission wavelengths of the emission module.

3. The assembly method according to claim 1, characterized in that, The multiple filters include multiple groups of filters, and each group of filters includes at least one filter; the center wavelengths of filters in the same group are equal, and the center wavelengths of filters in different groups are not equal; the number of filters included in each of the multiple groups of filters is positively correlated with the actual emission wavelength distribution of the emission module obtained according to statistics.

4. The assembly method according to claim 1, characterized in that, The lidar includes multiple transmitting modules; selecting a filter whose center wavelength matches the actual transmitting wavelength from among the multiple filters and assembling it at a preset position in the receiving module includes: Multiple filters whose center wavelength matches the actual emission wavelength of the multiple transmitting modules are assembled at preset positions on the receiving module, so that the multiple filters respectively receive the echo laser reflected from the emitted laser of the multiple transmitting modules.

5. The assembly method according to claim 1, characterized in that, The lidar includes multiple transmitting modules; The acquisition of multiple filters includes: dividing each filter into multiple filtering regions, each filtering region being used to receive the echo laser reflected from the emitted laser of the multiple emitting modules, and the combination of wavelength ranges allowed to pass through the multiple filtering regions of the multiple filters covering the emission wavelength range; The detection of the actual emission wavelength of the emitted laser includes: detecting the actual emission wavelength of the emitted laser from the plurality of emission modules; The step of selecting a filter whose center wavelength matches the actual emission wavelength from the multiple filters and assembling it at a preset position in the receiving module includes: selecting multiple filter regions whose center wavelengths correspond one-to-one with the actual emission wavelengths of the emitted lasers from the multiple transmitting modules and assembling them at a preset position in the receiving module.

6. The assembly method according to claim 5, characterized in that, The emission field of view of two adjacent emission modules overlaps in the plurality of emission modules; an overlapping region is provided between two adjacent filter regions corresponding to the two adjacent emission modules, and the bandwidth of the overlapping region is greater than or equal to the bandwidth of the two adjacent filter regions, so as to cover the wavelength range allowed to pass through the two adjacent filter regions.

7. A lidar, characterized in that, include: At least one transmitting module is used to emit an outgoing laser toward the detection area; A receiving module is used to receive the echo laser reflected by the target object in the detection area; The receiving module uses a filter to filter the echo laser. The filter used to filter the echo laser is adjustable so that the center wavelength of the filter used to filter the echo laser matches the actual emission wavelength of the emitted laser from the transmitting module. The actual emission wavelength is within the emission wavelength range, which is the difference between the preset emission wavelength of the emitted laser and the wavelength offset range. The wavelength offset range is caused by laser manufacturing tolerances and / or temperature variations. The filter uses a narrow bandwidth.

8. The lidar according to claim 7, characterized in that, The filter used to filter the echo laser is selected from a filter storage device that stores multiple filters; the combination of wavelength ranges allowed by the multiple filters covers the emission wavelength range; the filter used to filter the echo laser is set at a preset position in the receiving module; Alternatively, the lidar may contain multiple filters, the combination of wavelength ranges allowed by the multiple filters covering the emission wavelength range; the lidar may contain a first adjustment structure, the first adjustment mechanism being used to adjust the filter whose center wavelength matches the actual emission wavelength to a preset position of the receiving module; Alternatively, the filter may have multiple filtering regions, and the combination of wavelength ranges allowed by the multiple filtering regions covers the emission wavelength range; the lidar may have a second adjustment mechanism inside, which is used to adjust the filtering region whose center wavelength matches the actual emission wavelength to a preset position of the receiving module.

9. The lidar according to claim 8, characterized in that, When the filter used to filter the echo laser is selected from the filter storage device, the actual emission wavelength of the emitted laser from the emission module is detected by an external detection device. When the lidar is equipped with multiple filters or the filters have multiple filtering regions, the lidar is equipped with a detection mechanism, which is used to detect the actual emission wavelength of the emitted laser from the emitting module; the first adjustment mechanism adjusts the filter whose center wavelength matches the actual emission wavelength to a preset position of the receiving module according to the detection result of the detection mechanism, or the second adjustment mechanism adjusts the filtering region whose center wavelength matches the actual emission wavelength to a preset position of the receiving module according to the detection result of the detection mechanism.

10. A lidar, characterized in that, include: Multiple emission modules are used to emit laser beams into the detection area; A receiving module is used to receive the echo laser reflected by the target object in the detection area; The combination of the transmission fields of view of the multiple transmitting modules is matched with the receiving field of view of the receiving module; The receiving module is equipped with multiple filter units, each corresponding to one of the multiple transmitting modules, for filtering the echo laser reflected from the emitted laser of the multiple transmitting modules. The center wavelength of the wavelength range allowed by each filter unit matches the actual emission wavelength of the emitted laser of the corresponding transmitting module. The actual emission wavelength is within the emission wavelength range, which is the difference between the preset emission wavelength and the wavelength offset range of the emitted laser. The wavelength offset range is caused by laser manufacturing tolerances and / or temperature variations. All filter units employ narrow bandwidth.

11. The lidar according to claim 10, characterized in that, include: The emission fields of two adjacent emission modules overlap; an overlapping region is provided between two adjacent filter units corresponding to the two adjacent emission modules, and the bandwidth of the overlapping region is greater than or equal to the bandwidth of the two adjacent filter units, so as to cover the wavelength range allowed to pass through the two adjacent filter regions.

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