CN114646943A

CN114646943A - Receiving device, laser radar comprising same and detection method

Info

Publication number: CN114646943A
Application number: CN202011503088.0A
Authority: CN
Inventors: 刘豪; 朱雪洲; 许森; 向少卿
Original assignee: Hesai Technology Co Ltd
Current assignee: Hesai Technology Co Ltd
Priority date: 2020-12-17
Filing date: 2020-12-17
Publication date: 2022-06-21
Also published as: WO2022127078A1

Abstract

The invention provides a receiving device for laser radar, comprising: a receiving optical assembly configured to receive and converge an echo of a probe beam of a first wavelength band emitted by the laser radar reflected by a target object and a beam of a second wavelength band, wherein the second wavelength band does not include the first wavelength band; a beam splitting unit disposed downstream of the optical path of the receiving optical assembly and configured to separate a reflected echo of the probe beam from the optical path of the beam of the second wavelength band; the detection device comprises at least one group of detection units, is arranged on the optical path downstream of the light splitting unit, and is configured to receive the reflected echoes of the detection beams from the light splitting unit and convert the echoes into electric signals; and the imaging device comprises at least one group of imaging units, is arranged on the optical path downstream of the light splitting unit, and is configured to receive the light beams of the second wave band from the light splitting unit and image.

Description

Receiving device, laser radar comprising same and detection method

Technical Field

The present invention generally relates to the field of laser detection technology, and in particular, to a receiving device of a laser radar, a laser radar including the receiving device, and a detection method of the laser radar.

Background

The laser radar does not have the capability of obtaining true color images or the capability of distinguishing colors, and for many scenes such as traffic lights, the existing laser radar system cannot distinguish objects with the same shape and size but different colors when working alone.

With the development of automatic driving, more and more attention is paid to the fusion requirement of the point cloud information of the laser radar and the color image of the visible light camera. The existing methods for acquiring point cloud and image fusion information mainly include the following steps:

one way is to perform data fusion on the radar and the camera which work independently to obtain a color image and distance information. However, as two sets of devices with independent structures and working independently, the field of view (FOV) of the two devices needs to be aligned precisely, so that the field of view of the two devices is matched and time synchronized, and the required post-processing amount of data is very large, which results in a complex system structure and high cost.

The other is to capture image information and distance information simultaneously with the SPAD array, and obtain a grayscale image using the reflectivity information. However, the SPAD unit can generate avalanche when capturing single photon, and the SPAD array can reflect relatively low dynamic range of light intensity information, so that the resolution of the obtained image information is low. In addition, the requirements of the echo detection information and the image information on the ambient light are contradictory, the interference of the ambient light needs to be reduced as much as possible in the high-precision distance detection, but the high-precision image needs more ambient light information, so that the method has large limitation, and the distance precision and the image quality are difficult to be considered at the same time.

Compared with a mechanical scanning radar, the solid-state radar has no mechanical rotating part, so that the solid-state radar has the advantages of simple structure, miniaturization, low cost and long service life, and has great advantages in the development trend of future laser radars. However, the prior art is not suitable for a solid-state radar to acquire color image and point cloud data fusion information.

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

Disclosure of Invention

In view of at least one of the drawbacks of the prior art, the present invention provides a receiving apparatus usable with a lidar, comprising:

a receiving optical assembly configured to receive and converge an echo of a probe beam of a first wavelength band emitted by the lidar reflected by a target and a beam of a second wavelength band, wherein the second wavelength band does not include the first wavelength band;

a beam splitting unit disposed downstream of the optical path of the receiving optical assembly and configured to separate a reflected echo of the probe beam from the optical path of the beam of the second wavelength band;

the detection device comprises at least one group of detection units, is arranged on the optical path downstream of the light splitting unit, and is configured to receive the reflected echoes of the detection beams from the light splitting unit and convert the echoes into electric signals; and

the imaging device comprises at least one group of imaging units, is arranged on the optical path downstream of the light splitting unit, and is configured to receive the light beams of the second wave band from the light splitting unit and image the light beams;

wherein, each group of detection units and at least one group of imaging units correspond to the same field range.

According to an aspect of the invention, wherein the detection unit is a geiger-mode based detection unit.

According to an aspect of the invention, the detection device comprises a plurality of groups of detection units, wherein N groups of the detection units can be activated simultaneously to receive the reflected echoes, N is a positive integer greater than or equal to 1;

wherein the imaging device comprises a plurality of sets of imaging units, M sets of the plurality of sets of imaging units being simultaneously activatable to receive the light beams of the second wavelength band, M being a positive integer greater than or equal to 1.

According to an aspect of the present invention, the plurality of groups of detection units respectively correspond to different field ranges, and the field ranges corresponding to the plurality of groups of detection units form the detection range of the laser radar;

the multiple groups of imaging units respectively correspond to different view field ranges, and the view field ranges corresponding to the multiple groups of imaging units form the detection range of the laser radar.

According to one aspect of the invention, each group of detecting units is activated to receive the reflected echo at the same time, each group of imaging units is activated to receive the light beam of the second wave band and image, and the detecting units and the imaging units corresponding to the same field range are activated at the same time to detect and expose.

According to an aspect of the invention, wherein the imaging unit adjusts an exposure time according to an intensity of the light beam of the second wavelength band.

According to an aspect of the invention, wherein said detecting means and said imaging means are located in the focal plane of said receiving optical assembly.

According to an aspect of the invention, wherein the detection unit comprises a SPAD, the set of detection units comprises an array of SPADs; the imaging units comprise CMOS, and the group of imaging units comprise a CMOS pixel array.

According to an aspect of the present invention, wherein the light splitting unit includes a light splitting transreflective mirror, so that the reflected echo of the probe beam is reflected and the beam of the second wavelength band is transmitted, or so that the reflected echo of the probe beam is transmitted and the beam of the second wavelength band is reflected.

According to one aspect of the invention, wherein the surface of the spectroscopic transflector is coated with a highly reflective film or dichroic coating.

According to an aspect of the invention, wherein the light splitting unit comprises a grating to deflect the reflected echo of the probe light beam and the light beam of the second wavelength band into different directions.

According to an aspect of the present invention, the receiving apparatus further includes:

a first filter unit disposed upstream of the optical path of the probe device, the first filter unit having a pass band corresponding to the wavelength of the probe beam to allow the reflected echo of the probe beam to pass therethrough;

and the second filtering unit is arranged on the upstream of the optical path of the imaging device, and the stop band of the second filtering unit corresponds to the wavelength of the detection light beam so as to allow the light beam of the second waveband to pass through.

According to an aspect of the present invention, the receiving apparatus further comprises:

and the electronic diaphragm is arranged on the optical path downstream of the receiving optical element so as to enable the detection light beams corresponding to the detection field range to pass through and the ambient light to be filtered.

According to one aspect of the invention, the receiving device further comprises a processing unit configured to generate point cloud information according to the electrical signal output by the detecting device, and to register the point cloud information with the image information output by the imaging device to generate a color point cloud image.

The present invention also provides a laser radar comprising:

an emitting device including at least one laser light source configured to emit a probe beam to probe a target object;

the emitting optical assembly is positioned on the focal plane of the emitting optical assembly, and the emitting optical assembly is configured to receive the detection light beam emitted by the at least one laser light source, shape the detection light beam and emit the detection light beam to a target space; and

the receiving device as described above, configured to receive the echo of the probe beam reflected by the target object and the beam of the second wavelength band, and perform range detection and imaging on the target object;

the laser light source comprises at least one group of emission units, each group of emission units simultaneously emits the detection light beams, and at least one group of detection units corresponding to the field range are simultaneously activated to receive the reflection echoes.

According to one aspect of the invention, the laser light source comprises a plurality of groups of emission units, each group of emission units emits a detection light beam to different view field ranges, and the plurality of view field ranges form a detection range of the laser radar.

According to an aspect of the invention, each group of the emission units sequentially emits the detection beam to a corresponding field range, and at least one group of the detection units and at least one group of the imaging units corresponding to the field range are simultaneously activated to start detection and exposure.

According to an aspect of the invention, wherein the transmitting means comprises a plurality of laser light sources, the lidar comprises a plurality of transmitting optical assemblies, wherein each laser light source corresponds to one of the transmitting optical assemblies.

According to an aspect of the invention, the emitting device further comprises at least one fill-in light source configured to emit a light beam of a second wavelength band.

According to an aspect of the invention, the lidar further comprises a light intensity sensor arranged upstream in the optical path of the imaging device and configured to control the at least one fill-in light source to be turned on when the detected light intensity is lower than a threshold value.

According to an aspect of the invention, wherein the lidar is an area array flash lidar.

The invention also provides a detection method for simultaneously carrying out distance measurement and imaging by adopting the receiving device, which comprises the following steps:

s101: receiving an echo of a probe beam of a first waveband sent by a laser radar and a beam of a second waveband by a receiving optical assembly, and converging the reflected echo and the beam of the second waveband;

s102: separating the reflected echo of the probe beam and the optical path of the beam of the second waveband through a light splitting unit;

s103: receiving the reflected echo of the detection light beam through a detection device and converting the reflected echo into an electric signal; and

s104: and receiving and imaging the light beam of the second wave band by an imaging device.

According to an aspect of the present invention, wherein the detection unit is a geiger mode based detection unit, the detection method further comprises:

simultaneously activating each group of detection units to simultaneously receive the reflected echoes;

and simultaneously activating each group of imaging units so that the imaging units simultaneously receive and image the light beams of the second wave band.

According to an aspect of the present invention, wherein the detecting device includes a plurality of sets of detecting units, the imaging device includes a plurality of sets of imaging units, the detecting method further includes:

simultaneously activating N groups of the multiple groups of detection units to receive the reflected echoes, wherein N is an integer greater than or equal to 1;

and simultaneously activating M groups of the imaging units to receive the light beams of the second wave band, wherein M is an integer greater than or equal to 1.

According to an aspect of the present invention, wherein the plurality of sets of detecting units respectively correspond to different field of view ranges, and the plurality of sets of imaging units respectively correspond to different field of view ranges, the detecting method further comprises:

synthesizing the detection results of the multiple groups of detection units into a frame of point cloud;

and combining the imaging of the multiple groups of imaging units into a frame image.

According to an aspect of the invention, the detection method further comprises:

the detection unit and the imaging unit corresponding to the same field of view range perform the steps S103 and S104 at the same time.

According to an aspect of the present invention, wherein the step S104 further comprises:

and controlling the imaging unit to adjust the exposure time according to the intensity of the light beam of the second wave band.

According to an aspect of the present invention, wherein the step S102 further comprises:

and reflecting the reflection echo of the detection light beam and transmitting the light beam of the second wave band or transmitting the reflection echo of the detection light beam and reflecting the light beam of the second wave band by a beam splitting transflective mirror with a high reflection film coated on the surface.

and the beam of the second wave band is reflected or the reflected echo of the probe beam is reflected and the beam of the second wave band is transmitted through the beam splitting transflective mirror coated with the dichroic coating on the surface.

deflecting, by the grating, a reflected echo of the probe beam and the beam of the second wavelength band into different directions.

transmitting a reflected echo of the probe beam through a first filter unit disposed upstream of the optical path of the probe device; and

and transmitting the light beam with the second wave band by a second filtering unit arranged on the upstream of the optical path of the imaging device.

and the electronic diaphragm arranged at the downstream of the optical path of the receiving optical element enables the detection light beam corresponding to the detection field range to pass through, and the ambient light is filtered.

According to an aspect of the invention, wherein the lidar further comprises at least one fill-in light source configured to emit a light beam of a second wavelength band, the detection method further comprises:

and when the ambient light is lower than the threshold value, the supplementary lighting source is started.

According to an aspect of the present invention, wherein the lidar further comprises a light intensity sensor disposed upstream in the optical path of the imaging device, the detection method further comprises:

and when the light intensity detected by the light intensity sensor is lower than the threshold value, controlling the at least one light supplement light source to be started.

According to an aspect of the invention, wherein the lidar further comprises a processing unit, the detection method further comprises:

and the processing unit registers the point cloud information output by the detection device with the image information output by the imaging device to generate a color point cloud image.

The preferred embodiment of the invention provides a receiving device for a laser radar, wherein a receiving optical assembly is used for simultaneously obtaining point cloud data and a color image, the corresponding view fields of a detection device and an imaging device are completely the same and are completely synchronous in time, and then the image information and the point cloud information are registered on a software level, so that the fused image of the color image and the point cloud can be output. And complicated field matching or time synchronization is not needed, so that the complexity of the system and the manufacturing cost are reduced.

The preferred embodiment of the invention adopts a light splitting element to separate the light path of the near-infrared echo light beam and the light path of the visible light, thereby reducing the difficulty and the cost of the process. The number of SPADs that can be distributed in the SPAD array for ranging is not reduced, avoiding sacrificing ranging resolution in order to obtain image information.

In addition, the two sensor arrays can work independently, and parameters of the two sensors can be controlled respectively to improve detection and imaging performance, such as prolonging the exposure time of the imaging unit, and improving the imaging quality of a color image when ambient light is weak.

The area array flash solid-state laser radar of the preferred embodiment of the invention synchronously outputs the color image and the point cloud data which are completely matched with the time and the view field, the acquired information amount is greatly increased, and the invention is very beneficial to the accurate positioning and identification of the target object in the complex environment in the automatic driving application and provides reliable information for the automatic driving strategy.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention and not to limit the invention. In the drawings:

fig. 1 schematically shows a receiving apparatus according to a preferred embodiment of the present invention;

FIG. 2A schematically illustrates a detection apparatus according to a preferred embodiment of the present invention;

FIG. 2B schematically illustrates an imaging device according to a preferred embodiment of the present invention;

fig. 3 schematically shows a receiving apparatus according to a preferred embodiment of the present invention;

fig. 4 schematically shows a receiving apparatus according to a preferred embodiment of the present invention;

fig. 5 schematically shows a receiving apparatus according to a preferred embodiment of the present invention;

fig. 6 schematically shows a receiving apparatus according to a preferred embodiment of the present invention;

fig. 7 schematically shows a receiving apparatus according to a preferred embodiment of the present invention;

FIG. 8 schematically illustrates a lidar in accordance with a preferred embodiment of the present invention;

fig. 9 schematically shows a laser radar transceiving process according to a preferred embodiment of the present invention;

FIG. 10 schematically illustrates a lidar in accordance with a preferred embodiment of the present invention;

FIG. 11 schematically illustrates an arrangement of emission optical components according to a preferred embodiment of the present invention;

FIG. 12 schematically illustrates a lidar in accordance with a preferred embodiment of the present invention;

fig. 13 illustrates a detection method according to a preferred embodiment of the present invention.

Detailed Description

In the following, only certain exemplary embodiments are briefly described. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. Accordingly, the drawings and description are to be regarded as illustrative in nature, and not as restrictive.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", and the like, indicate orientations and positional relationships based on those shown in the drawings, and are used only for convenience of description and simplicity of description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be considered as limiting the present invention. Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", may explicitly or implicitly include one or more of the described features. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.

In the description of the present invention, it should be noted that unless otherwise explicitly stated or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection, either mechanically, electrically, or in communication with each other; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the present invention, unless otherwise expressly stated or limited, "above" or "below" a first feature means that the first and second features are in direct contact, or that the first and second features are not in direct contact but are in contact with each other via another feature therebetween. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly above and obliquely above the second feature, or simply meaning that the first feature is at a lesser level than the second feature.

The following disclosure provides many different embodiments or examples for implementing different features of the invention. To simplify the disclosure of the present invention, the components and arrangements of specific examples are described below. Of course, they are merely examples and are not intended to limit the present invention. Furthermore, the present invention may repeat reference numerals and/or letters in the various examples, such repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed. In addition, the present invention provides examples of various specific processes and materials, but one of ordinary skill in the art may recognize applications of other processes and/or uses of other materials.

The embodiments of the present invention will be described in conjunction with the accompanying drawings, and it should be understood that the embodiments described herein are only for the purpose of illustrating and explaining the present invention, and are not intended to limit the present invention.

The invention provides a receiving device of a laser radar, which can synchronously obtain a color image and distance information. According to a preferred embodiment of the present invention, as shown in fig. 1, there is provided a receiving apparatus 10 usable with a laser radar, including: receiving optics assembly 11, beam splitting unit 12, detection device 13 and imaging device 14. The receiving optical assembly 11 is configured to receive and converge an echo L1 of the probe light beam of the first wavelength band emitted by the laser radar reflected by the target object and a light beam L2 of a second wavelength band, wherein the second wavelength band does not include the first wavelength band. Preferably, the receiving optical assembly 11 is not wavelength selective, and light beams in both the infrared and visible bands are transmitted indiscriminately. The light splitting unit 12 is disposed downstream of the optical path of the receiving optical assembly 11 and configured to split the optical path of the reflected echo L1 of the probe light beam and the light beam L2 of the second wavelength band. The detection device 13 comprises at least one set of detection units 131, arranged in the optical path downstream of the light-splitting unit 12, configured to receive the reflected echo L1 of the detection light beam from the light-splitting unit 12 and convert it into an electrical signal. The imaging device 14 includes at least one set of imaging units 141 disposed downstream of the light path of the light splitting unit 12, and configured to receive and image the light beam L2 of the second wavelength band from the light splitting unit 12. Wherein each set of detecting units 131 corresponds to the same field of view as at least one set of imaging units 141. Preferably, a plurality of detecting units in each set of detecting units 131 are activated to receive the reflected echo L1 at the same time, and a plurality of imaging units in each set of imaging units 141 are activated to receive and image the light beam L2 of the second wavelength band at the same time.

Fig. 1 shows an embodiment in which the light splitting unit 12 reflects the light beam L1 in the first wavelength band, i.e. the reflected echo L1 of the probe light beam, and transmits the light beam L2 in the second wavelength band, and those skilled in the art can understand that the operation mode of the light splitting unit 12 is not limited thereto, and any receiving device that splits the reflected echo L1 of the probe light beam and the light beam L2 in the second wavelength band into two paths and synchronously performs distance detection and imaging is within the protection scope of the present invention.

The second wavelength band is preferably a visible light wavelength band, but the scope of the present invention is not limited thereto, and other wavelength bands (including a partially invisible light wavelength band) that can be used for imaging can be used as the second wavelength band besides the first wavelength band, and the light beam L2 of the second wavelength band and the reflected echo L1 of the first wavelength band are optically separated by the light splitting unit 12, the reflected echo L1 of the first wavelength band is received by the detecting device 13 and generates information related to the distance of the target object, and the light beam L2 of the second wavelength band is received and imaged by the imaging device 14.

Fig. 1 schematically illustrates an arrangement manner of the detection units 131 and the imaging units 141, and those skilled in the art can understand that the detection units 131 may be regularly arranged in a linear array or an area array manner or irregularly arranged on the detection device 13; the imaging units 141 may be regularly arranged in a linear array or an area array on the imaging device 14, or may be irregularly arranged, which are within the protection scope of the present invention.

According to a preferred embodiment of the present invention, wherein the detection unit 131 is a geiger-mode based detection unit. Preferably, the detection unit 131 is a Single Photon Avalanche Diode (SPAD), the detection device 13 includes at least one SPAD array, and the detection device 13 performs detection based on time-dependent photon counting; the imaging unit 141 is a CMOS sensor on which an RGGB filter is prepared or on which a filter is packaged to realize color image imaging, and the imaging device 14 includes at least one CMOS pixel array.

According to a preferred embodiment of the present invention, as shown in fig. 2A, the detecting device 13 comprises a plurality of groups of detecting units 131, in this embodiment, a plurality of detecting units in a group are configured to be activated simultaneously for detecting in response to the same enable signal. N groups of the multiple groups of detecting units 131 may be activated simultaneously to receive the reflected echoes L1, where N is a positive integer greater than or equal to 1. In fig. 2A, N is 2, and two groups of detection units shown in fig. 2 and having the same reference number share a common voltage source and are simultaneously activated for detection. For detection units based on the geiger mode, the activation may be to apply a bias voltage greater than the avalanche breakdown voltage to each detection unit, so that the detection unit is in the geiger mode, and a single photon may trigger the detection unit to avalanche output a detection signal.

As shown in fig. 2B, the imaging device 14 includes a plurality of groups of imaging units 141, and in the present embodiment, a plurality of imaging units in a group are configured to be simultaneously activated for imaging in response to the same enable signal. M groups of the plurality of groups of imaging units 141 may be simultaneously activated to receive the light beams L2 of the second wavelength band, M being a positive integer equal to or greater than 1. In fig. 2B, M is 3, and three groups of imaging units indicated by the same reference numerals in fig. 3 share a voltage source while applying a voltage to the imaging units to perform exposure.

According to a preferred embodiment of the present invention, the multiple groups of detecting units 131 correspond to different field ranges, for example, in fig. 2A, two groups of detecting units labeled a correspond to field ranges of 0 to 20 °, two groups of detecting units labeled B correspond to field ranges of 20 to 40 °, two groups of detecting units labeled C correspond to field ranges of 40 to 60 °, two groups of detecting units labeled D correspond to field ranges of 60 to 80 °, two groups of detecting units labeled E correspond to field ranges of 80 to 100 °, two groups of detecting units labeled F correspond to field ranges of 100 to 120 °, and the field ranges corresponding to the multiple groups of detecting units 131 form the detecting ranges of the laser radar, for example, the twelve groups of detecting units labeled a to F form the field ranges of the laser radar as shown in fig. 2A.

According to a preferred embodiment of the present invention, the multiple groups of imaging units 141 respectively correspond to different field ranges, taking fig. 2B as an example, three groups of imaging units labeled a correspond to field ranges of 0 to 20 °, three groups of imaging units labeled B correspond to field ranges of 20 to 40 °, three groups of imaging units labeled C correspond to field ranges of 40 to 60 °, three groups of imaging units labeled D correspond to field ranges of 60 to 80 °, three groups of imaging units labeled E correspond to field ranges of 80 to 100 °, three groups of imaging units labeled F correspond to field ranges of 100 to 120 °, and field ranges corresponding to the multiple groups of imaging units 141 constitute the detection range of the lidar, for example, eighteen groups of imaging units labeled a to F constitute field ranges of the lidar shown in fig. 2B.

According to a preferred embodiment of the present invention, the detecting unit 131 and the imaging unit 141 corresponding to the same field of view are activated simultaneously for detection and exposure. At least one group of SPAD units are adopted for detection every time, at least one group of CMOS sensor units are activated for imaging, namely, ranging every time, the same field angle is imaged, point cloud data of different field angles are detected in sequence, image information is generated in sequence, and finally synthesis is carried out. Taking fig. 2A and 2B as an example, the detecting unit and the imaging unit, which are labeled a, are activated simultaneously, and detection and imaging are started simultaneously; after a certain time interval, the detection unit and the imaging unit, labeled a, are deactivated, the detection unit and the imaging unit, labeled B, are activated, and detection and imaging of another field of view range is started at the same time. The detection units marked as A-F are sequentially activated by adopting the method, and a plurality of field ranges are sequentially detected to obtain a frame of point cloud data; the imaging units marked A-F are respectively activated simultaneously with the detection units with the same marks to sequentially image a plurality of field ranges to obtain a frame of image. And synthesizing one frame of point cloud data and one frame of image to obtain image and point cloud fusion information.

The CMOS device process is very mature, and a large-array CMOS device chip is easy to prepare, so that the CMOS array can be made larger than the SPAD array, namely, the number of groups of CMOS sensors or the number of CMOS sensors in each group of CMOS sensors can be more than the number of groups of SPADs or the number of SPADs in each group of SPADs in the array corresponding to a certain field range, and the image resolution can be improved.

According to a preferred embodiment of the present invention, wherein the imaging unit 141 adjusts the exposure time according to the intensity of the light beam L2 of the second wavelength band. Preferably, the second wavelength band is a visible light wavelength band, and the exposure time can be shortened when the ambient light is strong in the daytime, for example, the exposure time can be 1/1000s, 1/10000s, and the exposure time is increased as the light becomes dark, but the maximum exposure time does not exceed the activation time of the field range detection unit. Preferably, the multiple exposure is performed in the case where the ambient light is weak at night or on a cloudy day, the results of the multiple exposure are superimposed into one frame image, or the exposure time is extended in the case where the ambient light is weak.

According to a preferred embodiment of the invention, wherein the detection means 13 and the imaging means 14 are located in the focal plane of the receiving optical assembly 11.

According to a preferred embodiment of the present invention, the light splitting unit 12 comprises a light splitting mirror, so that the reflected echo L1 of the probe light beam is reflected and the light beam L2 of the second wavelength band is transmitted (as shown in FIG. 1), or so that the reflected echo L1 of the probe light beam is transmitted and the light beam L2 of the second wavelength band is reflected (as shown in FIG. 3).

According to a preferred embodiment of the invention, the surface of the spectro-mirror 12 is coated with a highly reflective film or dichroic coating.

In the preferred embodiment shown in fig. 1, the light splitting unit 12 employs a wavelength light splitting transflective mirror, taking a wavelength band of 940nm as a first wavelength band and a light band other than 940nm as a second wavelength band as an example, a high-reflection film of 940nm is coated on the surface of the wavelength light splitting transflective mirror 12, so that the laser light of the wavelength band of 940nm is reflected, and the detecting device 13 is disposed on a focal plane where the reflected echo L1 converges; infrared light having a wavelength deviated from 940nm and a visible light beam L2 can be transmitted therethrough and converged on the imaging device 14 at the focal plane position.

In the preferred embodiment shown in fig. 3, the light splitting unit 12 employs a wavelength splitting transflective mirror, taking a wavelength band of 905nm as a first wavelength band and a light band other than 905nm as a second wavelength band as an example, a dichroic coating is coated on the surface of the wavelength splitting transflective mirror 12, so that the echo light beam L1 of 905nm is transmitted through and received by the detecting device 13 for distance detection; infrared light having a wavelength deviated from 905nm and a visible light beam L2 are reflected to the imaging device 14 for imaging.

According to a preferred embodiment of the present invention, as shown in FIG. 4, the light splitting unit 12 includes a grating to deflect the reflected echo L1 of the probe light beam and the light beam L2 of the second wavelength band to different directions.

In the preferred embodiment shown in fig. 4, the light splitting unit 12 employs a grating, and the near infrared light and the visible light (for example, the near infrared band of the detection optical band is used as a first wavelength band, and the infrared light and the visible light which deviate from the detection optical band are used as a second wavelength band) are reflected to different angles by using the property that the grating can deflect the light with different wavelengths to different directions, and the detection device 13 and the imaging device 14 are respectively disposed at the corresponding optical path positions of the near infrared light of the detection optical band and the infrared light and the visible light which deviate from the detection optical band.

The light splitting unit provided by the invention can separate the light path of the light of the detection waveband from the light of other wavebands, and the light deviating from the detection waveband can be guided to the imaging device for imaging, so that the imaging light intensity can be enhanced to improve the imaging quality, the anti-interference effect can be realized, and the signal-to-noise ratio of the detection device can be improved.

According to a preferred embodiment of the present invention, as shown in fig. 5, the receiving device 10 further includes a first filter unit 15 disposed upstream in the optical path of the detecting device 13, and the pass band of the first filter unit 15 corresponds to the wavelength of the probe beam to allow the reflected echo L1 of the probe beam to pass therethrough. The receiving apparatus 10 further includes a second filter unit 16 disposed upstream in the optical path of the imaging apparatus 14, and a stop band of the second filter unit 16 corresponds to the wavelength of the probe light beam to allow the light beam L2 of the second wavelength band to pass therethrough.

Preferably, the first filtering unit 15 and the second filtering unit 16 are optical filters, and in order to improve the signal-to-noise ratio, an optical filter may be disposed in front of at least one SPAD array to filter out stray light outside the detection light wavelength; preferably, an optical filter can be arranged in front of at least one CMOS array to filter light in a detection light wave band, so that infrared light and visible light which deviate from the detection light wave band are highly transmitted, and the imaging quality is improved.

According to a preferred embodiment of the present invention, as shown in fig. 6, the receiving device 10 further comprises a first diaphragm 171 arranged optically upstream of the detecting device 13 and a second diaphragm 172 arranged optically upstream of the imaging device 14. The first diaphragm 171 and the second diaphragm 172 control the light of a specific field range to pass through the light-passing hole, so that the light beams received by the detecting unit group and the imaging unit group corresponding to the same field angle are from the same field angle, and the detecting and imaging corresponding to the same field angle are controlled.

According to a preferred embodiment of the present invention, as shown in fig. 7, the receiving device 10 further includes an electronic stop 173 disposed in the optical path downstream of the receiving optical element 11, so as to pass the light beam corresponding to the detection field range, and filter out the excessive ambient light. Wherein the electronic aperture 173 is a light modulator having "on" and "off" states, is arranged in the optical path downstream of the receiving optical element 11, and receives the light beam condensed by the receiving optical element 11. The light-passing area of the electronic diaphragm 17 corresponds to the position of the light spot of the detection device 14, i.e. to receive the light beam within the corresponding detection field.

As another preferred embodiment of the present invention, since the imaging device 14 does not require to filter out stray light, the electronic diaphragm 17 may also be disposed between the light splitting unit 12 and the detection device 13, the light-passing area of the electronic diaphragm 17 corresponds to the position of the light spot on the detection device 13, and other areas are closed to filter out stray light.

According to a preferred embodiment of the present invention, the receiving device 10 further includes a processing unit configured to generate point cloud information according to the electrical signal output by the detecting device 13, and to register the point cloud information with the image information output by the imaging device 14, so as to generate fusion information including a color image and co-view and co-time point cloud data.

According to a preferred embodiment of the present invention, as shown in fig. 8, the present invention also provides a laser radar 30 including: a transmitting device 20, a transmitting optical assembly 22 and a receiving device 10 as described above. The emitting device 20 comprises at least one laser light source 21 configured to emit a probe beam for detecting the object. The emission optical assembly 22 is configured to receive the probe beam emitted from the at least one laser light source 21 and shape the probe beam for emission to the target space, and the at least one laser light source 21 is located on a focal plane of the emission optical assembly 22. The receiving apparatus 10 as described above is configured to receive the echo L1 of the probe light beam reflected by the target object and the light beam L2 of the second wavelength band, and perform distance detection and imaging on the target object. Wherein the laser light source 21 comprises at least one set of emission units 211, each set of emission units 211 simultaneously emits a probe beam, and at least one set of detection units 131 corresponding to the field of view are simultaneously activated to receive the reflected echoes L1 of the probe beam.

Fig. 9 schematically shows the basic structure of a solid-state lidar that does not include mechanical rotating or scanning components, the laser source and the detection device both employ an area array, and the laser source includes at least one set of emitting units, such as a VCSEL array; the detection device comprises at least one group of detection units, such as SPAD array, which are respectively arranged on the focal plane of the transmitting optical assembly and the receiving optical assembly. Each set of emission units is independently addressable and each set of detection units is independently addressable.

As a detection mode of the solid-state laser radar, the VCSEL and the SPAD may be grouped and sequentially emit/detect light. As shown in fig. 9, at time t1, the first column of VCSELs on the emitting device emits light, the first column of SPADs on the corresponding detecting device is activated, and the first and second columns of CMOS sensors on the corresponding imaging device are simultaneously activated; at time t2, emitting light by a second row of VCSELs on the emitting device, activating a second row of SPADs on the corresponding detecting device to detect an echo signal, and activating a third row of CMOS sensors and a fourth row of CMOS sensors on the corresponding imaging device to perform exposure imaging; as described above, light emission of the VCSEL columns, and SPAD activation detection and CMOS activation imaging of the corresponding columns are performed in sequence. However, the protection scope of the present invention is not limited to the one-to-one correspondence relationship between the laser and the detector, and the emitting units may be grouped in rows or divided into a plurality of sub-arrays, and the grouping manner is not limited. It is within the scope of the present invention that at least one set of emission units simultaneously emit probe beams, at least one set of detection units corresponding to the field of view are simultaneously activated to receive reflected echoes of the probe beams, and at least one set of imaging units corresponding to the field of view are simultaneously activated to image.

According to a preferred embodiment of the present invention, the laser light source 21 comprises a plurality of sets of emission units 211, each set of emission units 211 emitting a probe beam to a different field of view, a plurality of said field of view constituting the detection range of the lidar 30. Preferably, at least one group of emission units corresponding to the field of view range of 0-20 degrees emits detection beams, at least one group of detection units corresponding to the field of view range of 0-20 degrees simultaneously performs distance detection, and at least one group of imaging units corresponding to the field of view range of 0-20 degrees simultaneously performs exposure imaging; or at least one group of emission units corresponding to the field of view range of 0-20 degrees is divided into a plurality of emission detection light beams, at least one group of detection units corresponding to the field of view range of 0-20 degrees performs distance detection during the emission detection light beams, and at least one group of imaging units corresponding to the field of view range of 0-20 degrees performs exposure imaging during the emission detection light beams.

According to a preferred embodiment of the present invention, wherein each set of emission units 211 sequentially emits the probe beam to a corresponding field of view range, at least one set of detection units 131 and at least one set of imaging units 141 corresponding to the field of view range are simultaneously activated to start detection and exposure.

According to a preferred embodiment of the present invention, as shown in fig. 10, wherein the transmitting device 20 comprises a plurality of laser light sources 21, the laser radar 30 comprises a plurality of transmitting optical assemblies 22, wherein each laser light source 21 corresponds to one of the transmitting optical assemblies 22.

The laser light source 21 is set to 2 or more, and 2 or more emitting optical assemblies 22 are correspondingly set and arranged on both sides of the receiving optical assembly 11, the detecting device 13 and the imaging device 14. The light emitted by each laser source 21 corresponds to a portion of the field of view, and different areas on the detector 13 correspond to echoes reflected by objects of different field angles. As shown in fig. 11, a plurality of transmitting optical assemblies 22 are arranged around the receiving optical assembly 11, and the arrangement shown in fig. 11 is such that two transmitting optical assemblies 22 and the receiving optical assembly 11 are arranged on the same straight line, and the transmitting optical assemblies 22 are respectively disposed on both sides of the receiving optical assembly 11. The number and arrangement of the emitting optical assemblies and the corresponding laser light sources shown in fig. 11 are only schematic, and more emitting optical assemblies 22 and more laser light sources may be provided, or a plurality of emitting optical assemblies 22 and corresponding laser light sources are not arranged on the same straight line with the receiving optical assembly, which is within the protection scope of the present invention.

In accordance with a preferred embodiment of the present invention, as shown in fig. 12, the emitting device 20 further includes at least one fill-in light source 23 configured to emit a light beam L2 of a second wavelength band. Preferably, on a cloudy day or at night when the ambient light is weak, the imaging device 14 may not obtain enough visible light for high-quality imaging, and the fill-in light source 23 may be turned on to provide auxiliary illumination of the visible light, thereby improving the imaging quality of the color image.

According to a preferred embodiment of the present invention, as shown in fig. 12, the lidar 20 further includes a light intensity sensor 31 disposed upstream in the optical path of the imaging device 14 and configured to control the at least one fill-in light source 23 to be turned on when the detected light intensity is lower than a threshold value. Preferably, in order to know the intensity of the visible light received by the imaging device 14, a light intensity sensor 31 may be disposed on the light path of the imaging device 14, a light intensity threshold may be set by the controller 32, and the fill-in light source 23 may be controlled to be turned on when the detected light intensity is lower than the threshold.

According to a preferred embodiment of the invention, the lidar 30 is an area array flash lidar. The area array flash laser radar is a solid laser radar without any mechanical scanning parts in the system.

According to a preferred embodiment of the present invention, as shown in fig. 13, the present invention also provides a detection method 100 for simultaneously performing ranging and imaging using the receiving apparatus 10 as described above (shown in fig. 1), including:

in step S101, the echo L1 of the probe light beam of the first wavelength band reflected by the target object and the light beam L2 of the second wavelength band emitted by the laser radar are received by the receiving optical assembly 11, and the reflected echo L1 and the light beam L2 of the second wavelength band are converged. Wherein the second wavelength band does not include the first wavelength band, the receiving optical assembly 11 is preferably not wavelength selective and light beams in both the infrared and visible wavelength bands are transmitted without distinction.

In step S102, the reflected echo L1 of the probe beam and the optical path of the light beam L2 of the second wavelength band are separated by the light splitting unit 12. Fig. 1 shows an embodiment in which the light splitting unit 12 reflects the light beam L1 in the first wavelength band, i.e. the reflected echo L1 of the probe light beam, and transmits the light beam L2 in the second wavelength band, and those skilled in the art can understand that the operation mode of the light splitting unit 12 is not limited thereto, and any method for splitting the reflected echo L1 of the probe light beam and the light beam L2 in the second wavelength band into two paths and synchronously performing distance detection and imaging is within the protection scope of the present invention.

In step S103, the reflected echo L1 of the probe beam is received by the probe device 13 and converted into an electrical signal.

In step S104, the light beam L2 of the second wavelength band is received by the imaging device 14 and imaged.

The detection method 100 of the preferred embodiment of the present invention employs two area array sensors, which cover two segments of wavelengths respectively, and the two area array sensors share a group of receiving lens groups. Therefore, the method has the advantage that in the full measurement range, two area array sensors can simultaneously see the same target. The two sensors do not need to be registered physically, and only need to be registered at the image level.

According to a preferred embodiment of the present invention, wherein the detecting unit 131 is a geiger-mode based detecting unit, the detecting method 100 further comprises:

simultaneously activating each group of detection units 131 so that they simultaneously receive reflected echoes L1;

each set of the imaging units 141 is simultaneously activated to simultaneously receive and image the light beam L2 of the second wavelength band.

According to a preferred embodiment of the present invention, wherein the detecting device 13 comprises a plurality of sets of detecting units 131, the imaging device 14 comprises a plurality of sets of imaging units 141, the detecting method 100 further comprises:

simultaneously activating N groups of the multiple groups of detection units 131 to receive the reflected echo L1, where N is an integer greater than or equal to 1;

m groups of the plurality of groups of imaging units 141 are simultaneously activated to receive the light beams L2 of the second wavelength band, M being an integer equal to or greater than 1.

According to a preferred embodiment of the present invention, wherein the plurality of sets of detecting units 131 correspond to different field of view ranges respectively, and the plurality of sets of imaging units 141 correspond to different field of view ranges respectively, the detecting method 100 further comprises:

synthesizing a frame of point cloud from the detection results of the plurality of groups of detection units 131;

the imaging by the plurality of sets of imaging units 141 is combined into one frame image.

According to a preferred embodiment of the present invention, the detection method 100 further comprises:

the detection unit 131 and the imaging unit 141 corresponding to the same field of view range simultaneously perform steps S103 and S104. The method comprises the steps of imaging the same field angle for each distance measurement, sequentially detecting point cloud data of different field angles, sequentially generating image information, and finally performing information synthesis.

According to a preferred embodiment of the present invention, wherein step S104 further comprises:

the imaging unit 141 is controlled to adjust the exposure time according to the intensity of the light beam L2 of the second wavelength band. Preferably, the second wavelength band is a visible light wavelength band, and the exposure time can be shortened when the ambient light is strong in the daytime, for example, the exposure time can be 1/1000s, 1/10000s, and the exposure time is increased as the light becomes dark, but the maximum exposure time does not exceed the activation time of the field range detection unit. In alternative embodiments, multiple exposures are performed at night or in the case of a cloudy day with weak ambient light, the results of the multiple exposures are superimposed into one frame of image, or the exposure time is extended in the case of weak ambient light.

According to a preferred embodiment of the present invention, as shown in fig. 1, wherein step S102 shown in fig. 13 further comprises:

the reflected echo L1 of the probe beam is reflected by the beam splitter 12 having a high reflection film coated on the surface thereof, and the beam L2 of the second wavelength band is transmitted.

According to a preferred embodiment of the present invention, as shown in fig. 3, wherein step S102 shown in fig. 13 further comprises:

the dichroic-coated dichroic mirror is passed through the spectroscopic mirror as the spectroscopic unit 12 so that the reflection echo L1 of the probe light beam is transmitted and the light beam L2 of the second wavelength band is reflected.

According to a preferred embodiment of the present invention, as shown in fig. 4, wherein step S102 shown in fig. 13 further comprises:

the reflected echo L1 of the probe beam and the beam L2 of the second wavelength band are deflected to different directions by the grating as the light splitting unit 12.

According to a preferred embodiment of the present invention, as shown in fig. 5, the detection method 100 shown in fig. 13 further comprises:

the reflected echo L1 of the probe beam is transmitted by a first filter unit 15 disposed upstream in the optical path of the probe device 13;

the light beam L2 of the second wavelength band is transmitted through the second filter unit 16 disposed on the optical path upstream of the imaging device 14.

According to a preferred embodiment of the present invention, as shown in fig. 6, the detection method 100 shown in fig. 13 further comprises:

the beam corresponding to the field of view of detection is passed through an electronic diaphragm 17 arranged optically downstream of the receiving optics 11, filtering out excess ambient light.

In accordance with a preferred embodiment of the present invention, as shown in fig. 12, wherein the lidar 30 further includes at least one fill-in light source 23 configured to emit a light beam L2 of a second wavelength band, the detection method 100 shown in fig. 13 further includes:

when the ambient light is lower than the threshold, the fill-in light source 23 is turned on.

According to a preferred embodiment of the present invention, as shown in fig. 12, wherein the lidar 30 further comprises a light intensity sensor 31 disposed upstream in the optical path of the imaging device 14, the detection method 100 shown in fig. 13 further comprises:

when the light intensity detected by the light intensity sensor 31 is lower than the threshold value, the at least one fill-in light source 23 is controlled to be turned on.

The preferred embodiment of the invention can be provided with the illuminating light source covering two wave bands, and can supplement light when the ambient light is weak and accurate imaging cannot be realized, so that a high-quality image can be obtained.

According to a preferred embodiment of the present invention, wherein the lidar further comprises a processing unit, the detection method 100 shown in fig. 13 further comprises:

the processing unit registers the point cloud information output by the detection device 13 with the image information output by the imaging device 14 to generate a color point cloud image.

The preferred embodiment of the invention can separate the light path of the near-infrared echo light beam from the light path of the visible light by adopting one light splitting element, and does not need to prepare two sensors on the same substrate or package the two sensors on one substrate, thereby reducing the difficulty and the cost of the process. The number of SPADs capable of being distributed in the SPAD array for ranging is not reduced, and the ranging resolution is prevented from being sacrificed for obtaining image information.

In addition, the two sensor arrays can work independently, the activation time of the detection unit can be set according to the detection requirement of the laser radar, the exposure time of the imaging unit can be flexibly adjusted according to the ambient light condition, and the imaging quality of the color image can be improved.

Finally, it should be noted that: although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that changes may be made in the embodiments and/or equivalents thereof without departing from the spirit and scope of the invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A receiving apparatus usable with a lidar comprising:

a receiving optical assembly configured to receive and converge an echo of a probe beam of a first wavelength band emitted by the laser radar reflected by a target object and a beam of a second wavelength band, wherein the second wavelength band does not include the first wavelength band;

2. The reception apparatus according to claim 1, wherein the detection unit is a geiger-mode-based detection unit.

3. The receiving device of claim 1 or 2, wherein the detecting device comprises a plurality of sets of detecting units, N sets of which can be activated simultaneously to receive the reflected echoes, N being a positive integer equal to or greater than 1;

4. The receiving apparatus according to claim 3, wherein the plurality of groups of detection units correspond to different field ranges respectively, and the field ranges corresponding to the plurality of groups of detection units constitute the detection range of the laser radar;

5. The receiving apparatus according to claim 4, wherein each group of detecting units is simultaneously activated to receive the reflected echoes, each group of imaging units is simultaneously activated to receive and image the light beams of the second wavelength band, and the detecting units and the imaging units corresponding to the same field of view are simultaneously activated to detect and expose.

6. The receiving device according to claim 5, wherein the imaging unit adjusts an exposure time according to an intensity of the light beam of the second wavelength band.

7. The receiving device of claim 1 or 2, wherein the detecting means and the imaging means are located in a focal plane of the receiving optical assembly.

8. The receiving apparatus of claim 2, wherein the detection unit comprises a SPAD, the set of detection units comprises an array of SPADs; the imaging units comprise CMOS, and the group of imaging units comprise a CMOS pixel array.

9. The receiving device according to claim 1 or 2, wherein the beam splitting unit includes a beam splitting transmirror so that the reflected echo of the probe beam is reflected, the beam of the second wavelength band is transmitted, or so that the reflected echo of the probe beam is transmitted and the beam of the second wavelength band is reflected.

10. The receiving device of claim 9, wherein a surface of the spectro-mirror is coated with a highly reflective film or a dichroic coating.

11. The receiving device according to claim 1 or 2, wherein the beam splitting unit comprises a grating to deflect the reflected echo of the probe beam and the beam of the second wavelength band into different directions.

12. The reception apparatus according to claim 1 or 2, further comprising:

13. The reception apparatus according to claim 3, further comprising:

14. The receiving apparatus according to claim 1 or 2, further comprising a processing unit configured to generate point cloud information from the electrical signal output by the detecting apparatus and to register the point cloud information with the image information output by the imaging apparatus, generating a color image and point cloud fusion information.

15. A lidar comprising:

the receiving device of any one of claims 1-14, configured to receive an echo of the probe beam reflected by a target object and a beam of a second wavelength band, and perform range detection and imaging on the target object;

16. The lidar of claim 15, wherein the laser light source comprises a plurality of sets of transmit units, each set of transmit units transmitting a probe beam to a different field of view range, a plurality of the field of view ranges constituting a detection range of the lidar.

17. The lidar as claimed in claim 15 or 16, wherein each set of the transmitting units sequentially emits a probe beam to a corresponding field of view, and at least one set of the detecting units and at least one set of the imaging units corresponding to the field of view are simultaneously activated to start detection and exposure.

18. The lidar of claim 15, wherein the transmitting device comprises a plurality of laser light sources, the lidar comprising a plurality of transmitting optical assemblies, wherein each laser light source corresponds to one of the transmitting optical assemblies.

19. The lidar of claim 15 or 18, wherein the transmitting means further comprises at least one fill light source configured to emit a light beam in a second wavelength band.

20. The lidar of claim 19, further comprising a light intensity sensor disposed in the optical path upstream of the imaging device and configured to control the at least one fill light source to turn on when the detected light intensity is below a threshold.

21. The lidar of claim 15 or 18, wherein the lidar is an area array flash lidar.

22. A detection method for simultaneous ranging and imaging using the receiving apparatus of any one of claims 1-14, comprising:

23. The detection method of claim 22, wherein the detection unit is a geiger-mode based detection unit, the detection method further comprising:

24. The detection method according to claim 22 or 23, wherein the detection apparatus includes a plurality of sets of detection units, the imaging apparatus includes a plurality of sets of imaging units, the detection method further comprising:

25. The detection method according to claim 24, wherein the plurality of sets of detection units respectively correspond to different field-of-view ranges, and the plurality of sets of imaging units respectively correspond to different field-of-view ranges, the detection method further comprising:

26. The detection method of claim 25, further comprising:

27. The detection method of claim 26, wherein the step S104 further comprises:

28. The detection method according to claim 22 or 23, wherein the step S102 further comprises:

29. The detection method according to claim 22 or 23, wherein the step S102 further comprises:

30. The detection method according to claim 22 or 23, wherein the step S102 further comprises:

31. A detection method according to claim 22 or 23, further comprising:

and transmitting the light beam of the second waveband through a second filtering unit arranged on the upstream of the optical path of the imaging device.

32. The detection method of claim 22 or 23, further comprising:

33. A detection method according to claim 22 or 23, wherein the lidar further comprises at least one fill-in light source configured to emit a light beam in a second wavelength band, the detection method further comprising:

34. A detection method according to claim 33, wherein said lidar further comprises a light intensity sensor disposed in the optical path upstream of said imaging device, said detection method further comprising:

35. The detection method of claim 22 or 23, wherein the lidar further comprises a processing unit, the detection method further comprising:

and the processing unit registers the point cloud information output by the detection device with the image information output by the imaging device to generate a color image and point cloud fusion information.