Detection device, lidar and terminal

Abstract

A detection device (10), a lidar and a terminal, which are applied to the technical field of detection. The detection device (10) comprises a transceiving module (11) and a rotating mirror (12), wherein the rotating mirror (12) comprises a plurality of reflecting surfaces (R1, R2, R3, R4, R5), the rotating mirror (12) has a pyramidal error of a first angle (α), and the pyramidal error enables the included angles between the plurality of reflecting surfaces (R1, R2, R3, R4, R5) and a cross section of the rotating mirror (12) to be equally distributed at an angular difference of the first angle (α); and the transceiving module (11) comprises a plurality of transceiving ports (1101), and the plurality of transceiving ports (1101) can generate a plurality of transmitting beams (#1, #2, #3, #4, #5, #6, #7, #8) having different pointing angles. The combination of the multiple channels of transmitting beams (#1, #2, #3, #4, #5, #6, #7, #8) having different pointing angles and the rotating mirror (12) having the pyramidal error implements encrypted scanning and uniform scanning, and can significantly improve the resolution of the detection device, and control the manufacturing cost of the detection device (10), thereby facilitating the realization of low power consumption, high reliability and miniaturization of the lidar and the terminal.

Description

A detection device, a laser radar and a terminal TECHNICAL FIELD

[0001] The present application relates to the technical field of detection, and in particular to a detection device, a laser radar and a terminal. BACKGROUND

[0002] Light detection and ranging (LIDAR) technology, i.e., a laser radar, obtains relevant information (e.g., characteristic quantities such as the position, shape, or speed of a target) of a target by emitting a detection light beam and receiving a return wave of the target. The laser radar can accurately measure the distance and position of the target, but the resolution of the laser radar is limited due to factors such as power consumption and the divergence angle of the light beam.

[0003] Some manufacturers improve the resolution by increasing the number of light beams emitted by the laser radar. However, a small increase in the number of channels does not significantly improve the resolution, and a large increase in the number of light beams emitted by the laser radar will inevitably affect the manufacturing cost of the laser radar, and is not conducive to the reliability, low power consumption, and miniaturization design of the laser radar. For example, if a large number of light beams are emitted, the volume of the emission module, lens, and the like will also increase significantly, and the volume of the laser radar will also increase accordingly, such as the height of the laser radar in the vertical direction will increase significantly. In addition, a large increase in the number of light beams emitted by the laser radar also requires a corresponding increase in the emission power of the laser radar, and therefore additional design is required for heat management and current noise processing.

[0004] How to improve the resolution of the laser radar without significantly increasing the cost of the laser radar is a hot issue being studied by those skilled in the art.

[0005] SUMMARY

[0006] The present application provides a detection device, a laser radar and a terminal, which combines a multi-channel emission beam and a rotating mirror with a tower difference to realize encrypted scanning and uniform scanning, thereby significantly improving the resolution of the detection device. The combination of the rotating mirror to realize encrypted scanning and uniform scanning makes it unnecessary to significantly increase the number of light beams generated by the emission module, thereby reducing the manufacturing cost of the detection device, and being conducive to the realization of low power consumption, high reliability, and miniaturization of the laser radar and the terminal.

[0007] In a first aspect, the present application provides a detection device, comprising a transceiver module and a rotating mirror. The rotating mirror comprises M reflecting surfaces, M being an integer and M≥2. The angles between the M reflecting surfaces and a first plane are distributed in an arithmetic progression with a first angle difference of a first angle α, and the first plane is perpendicular to the activity axis of the rotating mirror. The transceiver module comprises at least N transceiver ports, N being an integer and N≥4. The transceiver module is configured to generate N emission light beams, and the pointing angles of the N emission light beams are different.

[0008] The N transmitting beams are reflected to the object space through the rotating mirror, the N transmitting beams include adjacent first and second beams, and the included angle between the pointing angles of the first and second beams is a second angle x. The first angle a and the second angle x satisfy the following relationship: x = M x a.

[0009] In the present application, the rotating mirror has a first angle a of the tower difference, and the included angles between each reflecting surface and the cross section (i.e., the first plane) of the rotating mirror are distributed in an arithmetic progression with an angle difference of a. For example, the included angle between the reflecting surface R1 and the first plane is b, and the included angle between the reflecting surface R2 and the first plane is b+a. The N scanning lines formed after the N transmitting beams are scanned by the reflecting surface R2 have an angle deviation of a relative to the N scanning lines formed after the N transmitting beams are scanned by the reflecting surface R1. By analogy, after being reflected by the M reflecting surfaces, the corresponding detection regions are scanned M times by the N transmitting beams, the total number of lines is M x N, and the M scans are uniformly spaced by the first angle a, achieving encrypted scanning and uniform scanning, which can significantly improve the resolution of the detection device.

[0010] Further, the first and second beams are spaced apart by a second angle x, which makes the M scanning lines formed after the first beam undergoes M scans not overlap with the M scanning lines formed after the second beam undergoes M scans, and the two are spaced apart by the first angle a. In this way, the 2 x M scanning lines formed after the first and second beams pass through the M reflecting surfaces are uniformly distributed with a spacing of the first angle a. This further improves the uniformity of scanning, thereby reasonably allocating the beam resources of the detection device and improving the detection efficiency.

[0011] In some scenarios, the M x N beams are arranged along a direction perpendicular to a horizontal plane, which can be the ground, or the bottom surface of the laser radar where the detection device is located. In this scenario, the scheme of the present application can significantly improve the vertical resolution of the detection device.

[0012] In a possible implementation of the first aspect, the M reflecting surfaces are used to rotate around the active shaft to scan the N transmitting beams to the object space in different time periods, and the scanning trajectories of the N transmitting beams after being reflected by the M reflecting surfaces are M x N scanning lines. In this way, the present application can achieve M times of encrypted scanning, significantly improving the resolution of the detection device.

[0013] Further, the M x N scanning lines are arranged with a spacing, and any two scanning lines do not overlap. Further, the spacing between the scanning lines proposed in the present application can refer to the spacing along the arrangement direction of the N scanning lines.

[0014] In a further possible implementation form of the first aspect, the 2 x M scanning lines formed by the first bundle and the second bundle after passing through the M reflecting surfaces are uniformly distributed at intervals of the first angle a.

[0015] In a further possible implementation form of the first aspect, the second angle x is a maximum value of an included angle between pointing angles of adjacent ones of the N emission bundles. In this way, among the M x N scanning lines, a maximum angle interval between the scanning lines, i.e. the first angle a, ensures a resolution of the detection device.

[0016] In a further possible implementation form of the first aspect, the N emission bundles comprise K third bundles adjacent to each other, and an included angle between pointing angles of any two adjacent ones of the K third bundles is a third angle yl. Further, the third angle yl satisfies the following relationship:

[0017] yl * K = a,

[0018] where K is a positive integer, e.g. K is an integer and K > 2, such as 2, 3, 4, etc.

[0019] Taking the reflecting surface Rl and the reflecting surface R2 as an example, an included angle between the reflecting surface Rl and the first plane is b, and an included angle between the reflecting surface R2 and the first plane is b + a. For the same emission bundle, there is an angle deviation of a between scanning tracks formed after passing through the reflecting surface Rl and the reflecting surface R2, respectively. At this time, if the K emission bundles are designed as a group, then after passing through the reflecting surface Rl and the reflecting surface R2 once, the scanning lines formed by the K emission bundles can be uniformly distributed within the angle deviation a formed by twice scanning. By analogy, after the M scanning surfaces are scanned respectively, the scanning lines formed by the K emission bundles are uniformly distributed, so that the encrypted scanning and the uniform scanning can be realized.

[0020] In a further possible implementation form of the first aspect, the K x M scanning lines formed by the K third bundles after passing through the M reflecting surfaces are uniformly distributed at intervals of the third angle yl.

[0021] In a further possible implementation form of the first aspect, an angle formed by the first bundle and the second bundle is closer to an edge of the N emission bundles than an angle formed by the K third bundles. In this way, among a field of view formed after scanning of the N emission bundles, a scanning line interval is larger in an edge region and smaller in a middle region, so as to facilitate to encrypt scanning of the middle region of the field of view, and a resolution of the middle region is K times of a resolution of the edge region.

[0022] In some scenarios, improving the detection accuracy of the middle region can effectively improve the value of the detection result and is beneficial to the calculation and decision related to the perception result. For example, the present application can be applied in vehicle perception, intelligent driving, mapping, robot perception and the like. Taking the vehicle perception scenario as an example, the central region of the field of view usually includes the space where the vehicle is most likely to travel, which is the high-value field of view range, i.e., the region of interest (ROI). Through the scheme of the present application, the detection accuracy of the ROI can be improved, and thus the driving safety of the vehicle is improved. Especially for the intelligent driving system, the higher the detection accuracy of the ROI, the more beneficial to the calculation and decision of the intelligent driving system, thereby improving the safety and comfort of the intelligent driving system.

[0023] In a further possible implementation form of the first aspect, the N emission beams further comprise a fourth beam, the K third beams and the fourth beam are sequentially adjacent, an included angle between the fourth beam and a fifth beam is a fourth angle z1, the fifth beam is a beam closest to the fourth beam among the K third beams, the third angle y1 and the fourth angle z1 satisfy the following relationship:

[0024] z1 + (K-1) y1 = M x a.

[0025] In the above implementation form, there is an angle difference z1 between the fourth beam and the K third beams. By designing the angle relationship between z1 and y1, M and a, M times of encryption scanning can be realized, and the resolution of the detection device is significantly improved.

[0026] In a further possible implementation form of the first aspect, the K x M scanning lines formed by the K third beams after passing through the M reflecting surfaces are a first scanning line group, and the M scanning lines formed by the fourth beam after passing through the M reflecting surfaces are a second scanning line group. The first scanning line group and the second scanning line group do not overlap, and an angle interval between the edge of the first scanning line group close to the second scanning line group and the edge of the second scanning line group close to the first scanning group is a third angle y1. In this way, the uniformity of the scanning line distribution can be further improved, and the proportion of the high-resolution region is increased.

[0027] In a further possible implementation form of the first aspect, the N emission beams comprise J sixth beams and a seventh beam which are sequentially adjacent, and an included angle of a pointing angle between any two adjacent beams among the J sixth beams is a fifth angle y2. The fifth angle y2 satisfies the following relationship:

[0028] y2 * J = a,

[0029] wherein J is a positive integer, for example, J is an integer and J≥2, such as 2, 3, 4, etc. The angle between the seventh beam and the eighth beam is a sixth angle z2, and the eighth beam is the beam closest to the seventh beam among the J sixth beams. The sixth angle z2 and the fifth angle y2 satisfy the following relationship:

[0030] z2=M x a.

[0031] In yet another possible implementation of the first aspect, the J sixth beams form J x M scanning lines after passing through the M reflecting surfaces, and the J x M scanning lines are uniformly distributed at intervals of a fifth angle y2. The seventh beam forms M scanning lines after passing through the M reflecting surfaces, and the M scanning lines form a fourth scanning line group. The third scanning line group and the fourth scanning line group do not overlap, and the angle interval between the edge of the third scanning line group close to the fourth scanning line group and the edge of the fourth scanning line group close to the third scanning line group is a first angle a. In this way, the uniformity of the scanning line distribution can be further improved.

[0032] In yet another possible implementation of the first aspect, the angle formed by the first beam and the second beam is closer to the edge of the N emitting beams than the angle formed by the J sixth beams.

[0033] In yet another possible implementation of the first aspect, the N emitting beams include a ninth beam and a tenth beam adjacent to each other, and the angle between the pointing angles of the ninth beam and the tenth beam is a seventh angle y3. The seventh angle y3 satisfies the following relationship:

[0034] y3*2=M x a.

[0035] The above implementation can cause the M scanning lines formed by the ninth beam and the M scanning lines formed by the tenth beam to be interleaved, and the resolution of the interleaved region can be doubled compared to the resolution of the non-interleaved region.

[0036] In yet another possible implementation of the first aspect, the ninth beam forms a fifth scanning line group after passing through the M reflecting surfaces, and the tenth beam forms a sixth scanning line group after passing through the M reflecting surfaces. The half of the fifth scanning line group close to the sixth scanning line group is interleaved with the half of the sixth scanning line group close to the fifth scanning line group, and the scanning lines of the interleaved part of the fifth scanning line group and the sixth scanning line group are uniformly distributed at intervals of a / 2. In this way, the uniformity of the scanning line distribution can be further improved, and the resolution of the detection device can be improved.

[0037] Optionally, multiple groups of the ninth beam and the tenth beam can be arranged in the detection device to form a high-resolution region, which helps to further improve the resolution of the ROI.

[0038] In a further possible implementation form of the first aspect, the angle formed by the first wire harness and the second wire harness is closer to an edge of the N emission beams than the angle formed by the ninth wire harness and the tenth wire harness. In this way, in the field of view formed by the N emission beams after scanning, the scanning lines in the edge region are spaced farther apart, and the scanning lines in the middle region are spaced closer together, thereby facilitating the scanning of the middle region of the field of view, and the resolution of the middle region is twice that of the edge region.

[0039] In a further possible implementation form of the first aspect, the scanning lines in a region of interest (ROI) of the field of view of the detection device are more densely distributed than the scanning lines in a non-ROI of the field of view. In this way, the scanning lines in the ROI region are designed to be spaced closer together, and the scanning lines are more densely distributed, so that the resolution of the detection device in the ROI region can be accurately detected, the usability of the detection result of the detection device is improved, and the practicability is improved.

[0040] In a further possible implementation form of the first aspect, the detection device further comprises a lens, and the lens is arranged between the N transceiver ports and the rotating mirror. In the N emission beams, the included angle θ of the pointing angles between two emission beams is related to the distance d between the transceiver ports corresponding to the two emission beams and the focal length g of the lens.

[0041] Exemplarily, the included angle θ of the pointing angles satisfies the following relationship:

[0042] In a further possible implementation form of the first aspect, each of the N emission beams comprises a frequency modulated continuous wave (FMCW). The frequency of the FMCW varies with time, and the variation law includes one or more of sawtooth, triangle or sine. Since the variation of the frequency feature needs a certain time length to be reflected, when using a coherent radar to measure, the measurement time is often relatively long, the number of target points obtained is small, and the resolution is low. The present application can encrypt and uniformly scan the detection region, can improve the resolution of the FMCW laser radar, and thereby significantly improve the detection accuracy of the FMCW.

[0043] In a further possible implementation form of the first aspect, the transceiver module further comprises at least one laser group, and each laser group comprises a laser, and the laser is configured to generate a light beam.

[0044] In a further possible implementation form of the first aspect, each of the N transmit beams comprises beams from at least two lasers. Further, the beams from the at least two lasers are different in at least one property, i.e. at least one attribute is different. For example, the beams from the at least two lasers are different in at least one of a sweep slope, a frequency and a wavelength.

[0045] In this way, by using two lasers with different beam properties, after receiving the return beams, the local oscillator signals corresponding to the two lasers can be mixed respectively in the mixing stage, the number of obtained target points (i.e. the out-point rate) is increased, and the detection accuracy is improved.

[0046] In a further possible implementation form of the first aspect, each of the N transmit beams comprises a beam from one laser.

[0047] In a further possible implementation form of the first aspect, the transceiver module is further configured to receive the N receive beams.

[0048] In a further possible implementation form of the first aspect, the transceiver module further comprises a plurality of mixers, each of the plurality of mixers corresponding to at least one of the N transmit beams and at least one of the N receive beams. Each of the plurality of mixers is configured to mix the local oscillator beam of the corresponding at least one of the N transmit beams with the corresponding at least one of the N receive beams to obtain a mixing result.

[0049] In a further possible implementation form of the first aspect, the mixer is a 90° mixer or a 180° mixer.

[0050] In a further possible implementation form of the first aspect, the transceiver module comprises N transceiver ports and N mixers, and the N transceiver ports and the N mixers are arranged in an interleaved manner along a direction of arrangement of the N transceiver ports. Since the mixers need to receive the local oscillator signals and the receive beams received by the transceiver ports, interleaving the N transceiver ports and the N mixers can reduce the intersection points of the optical paths and reduce the noise of the beams, thereby improving the detection accuracy.

[0051] In a further possible implementation form of the first aspect, the N transceiver ports are further configured to receive the N receive beams, and the transceiver module further comprises a plurality of optical loopback devices. Each of the plurality of optical loopback devices comprises a first port, a second port and a third port, the second port is connected to at least one of the transceiver ports, and the third port is connected to one of the mixers. The optical loopback device is configured to receive a to-be-transmitted beam from the first port and output the to-be-transmitted beam from the second port to be emitted from the corresponding transceiver port. The optical loopback device is further configured to obtain a receive beam provided by the corresponding transceiver port and output the receive beam from the third port to the corresponding mixer. In a further possible implementation form of the first aspect, the transceiver module further comprises a plurality of optical loopback devices. Each of the plurality of optical loopback devices comprises a first port, a second port and a third port, the second port is connected to at least one of the transceiver ports, and the third port is connected to one of the mixers. The optical loopback device is configured to receive a to-be-transmitted beam from the first port and output the to-be-transmitted beam from the second port to be emitted from the corresponding transceiver port. The optical loopback device is further configured to obtain a receive beam provided by the corresponding transceiver port and output the receive beam from the third port to the corresponding mixer.

[0052] Exemplarily, the optical loopback device includes, but is not limited to, a polarizing beam splitter (PBS), a PRS polarizing rotator (PBS), a polarized beam rotator splitter (PBRS), etc. Among them, the PBSR is also referred to as a polarized beam splitter rotator (PBSR) in some schemes.

[0053] In the above-mentioned embodiments, the optical loopback device can realize the coaxial transmission and reception, so that the transmission field of view and the reception field of view are matched, the detection accuracy can be improved, and the field of view range of the detection device can also be improved.

[0054] In a further possible implementation form of the first aspect, the transceiver module includes M transceiver ports, M being an integer and M>N. The plurality of optical loopback devices includes a first optical loopback device, a second port of the first optical loopback device being connected to a root end of an optical switch tree, leaf ends of the optical switch tree being connected to the plurality of transceiver ports, the optical switch tree including a plurality of optical switches arranged in a tree structure. The optical switch tree is configured to select one of the transceiver ports, so that a to-be-transmitted beam from the second port of the first optical loopback device is emitted from the selected transceiver port.

[0055] In the above-mentioned embodiments, the optical switch tree is used to select any port, so that the position of the port of the emitted beam can be adjusted. Accordingly, the interval between the ports of the two emitted beams can also be adjusted. Further, since the interval between the ports affects the pointing angle between the beams, the above-mentioned embodiments can realize the adjustable pointing angle between the beams, and the pointing angle between the beams can be adjusted according to the requirements, so as to meet the resolution requirements in various scenarios and improve the application flexibility of the detection device.

[0056] In a further possible implementation form of the first aspect, the transceiver module includes M transceiver ports, M being an integer and M>N. The N optical loopback devices include a second optical loopback device, a second port of the second optical loopback device being connected to a root end of a beam splitter tree, leaf ends of the beam splitter tree being connected to the plurality of transceiver ports, the beam splitter tree including a plurality of beam splitters arranged in a tree structure. The beam splitter tree is configured to split the beam received from the root end into multiple paths and emit the multiple paths from the plurality of transceiver ports connected to the leaf ends, respectively.

[0057] In a further possible implementation form of the first aspect, the transceiver module includes a silicon optical chip, the silicon optical chip including an entry port, at least N transceiver ports, and an optical waveguide, the optical waveguide being configured to transmit a beam between components of the silicon optical chip.

[0058] The components of the silicon optical chip include an entering port and a transceiving port. Optionally, the silicon optical chip further includes a plurality of mixers and a plurality of optical loopback devices.

[0059] In a further possible implementation form of the first aspect, the silicon optical chip further includes a first beam splitter, a second beam splitter, a first beam combiner, a first beam splitter tree and a feedback module. The first beam splitter is configured to split a first laser into a first light beam and a second light beam, the second beam splitter is configured to split a second laser into a third light beam and a fourth light beam, the first beam combiner is configured to combine the first light beam and the third light beam into a first combined light beam, the first beam splitter tree is configured to split the first combined light beam into a first feedback light beam, a plurality of first to-be-emitted light beams and a plurality of first local oscillator light beams, the plurality of first to-be-emitted light beams are input into the plurality of optical loopback devices respectively, the plurality of first local oscillator light beams are input into the plurality of mixers respectively, and the feedback module is configured to mix the first feedback light beam with the second light beam and the fourth light beam respectively to obtain a feedback result.

[0060] Further, the first beam splitter, the second beam splitter, the first beam combiner, the first beam splitter tree and the feedback module can be regarded as a set of optical processing modules. The silicon optical chip can include a plurality of optical processing modules to process a plurality of light sources, so as to increase the number of emission beams and ensure the emission power of each emission beam. Optionally, some modules can be shared in the plurality of optical processing modules, for example, some optical waveguides (i.e., some optical paths can be combined) or feedback modules.

[0061] In a further possible implementation form of the first aspect, the silicon optical chip does not include an optical amplifier. In this way, the power consumption of the detection device can be reduced. Since the optical amplifier needs to be supported by a large current, the design of the optical amplifier can reduce the heat generated by the silicon optical chip and improve the reliability of the silicon optical chip.

[0062] In some schemes, since the resolution is improved without a large increase in the number of channel beams, the emission power of each emission beam can meet the detection requirements, and the design of the optical amplifier will not cause a significant reduction in the emission power.

[0063] In a further possible implementation form of the first aspect, the plurality of first to-be-emitted light beams and the plurality of first local oscillator light beams are arranged in a cross arrangement. Since the local oscillator light beams need to be mixed with the corresponding receiving beams of the emission beams, the cross arrangement can reduce the intersection points of the optical paths, reduce the noise level and improve the detection accuracy of the detection device.

[0064] In a second aspect, the present application provides a laser radar, which includes the detection device described in the first aspect or any possible implementation form of the first aspect.

[0065] In a possible implementation form of the second aspect, the lidar further comprises a signal processing device configured to control the detection device and / or process data output by the detection device, such as a mixing result, or a TOF resolving result, etc.

[0066] In a further possible implementation form of the second aspect, the lidar further comprises a housing configured to accommodate the detection device.

[0067] In a third aspect, the present application provides a terminal, which comprises the detection device of the first aspect or any possible implementation form of the first aspect, or comprises the lidar of the second aspect or any possible implementation form of the second aspect.

[0068] Optionally, the terminal is an intelligent terminal or a vehicle, such as a vehicle, a drone, or a robot.

[0069] The beneficial effects of the second aspect to the third aspect of the present application can be referred to the beneficial effects of the first aspect, which will not be described one by one. BRIEF DESCRIPTION OF DRAWINGS

[0070] The drawings needed to be used in the following embodiment description will be briefly introduced.

[0071] Fig. 1 is a structural schematic diagram of a detection device according to an embodiment of the present application;

[0072] Fig. 2 is a structural schematic diagram of a four-face rotating mirror according to an embodiment of the present application;

[0073] Fig. 3 is a schematic diagram of a pointing angle of a plurality of emission beams according to an embodiment of the present application;

[0074] Fig. 4 is a schematic diagram of an implementation form of a pointing angle according to an embodiment of the present application;

[0075] Fig. 5 is a schematic diagram of a scanning track of an emission beam after passing through a plurality of scanning surfaces according to an embodiment of the present application;

[0076] Fig. 6 is a schematic diagram of a scanning track of an emission beam after passing through a plurality of scanning surfaces according to an embodiment of the present application;

[0077] Fig. 7 is a schematic diagram of a scanning track of an emission beam after passing through a plurality of scanning surfaces according to an embodiment of the present application;

[0078] Fig. 8 is a schematic diagram of a scanning track of an emission beam after passing through a plurality of scanning surfaces according to an embodiment of the present application;

[0079] Fig. 9 is a schematic diagram of a scanning track of an emission beam after passing through a plurality of scanning surfaces according to an embodiment of the present application;

[0080] FIG. 10 is a schematic diagram of a scanning trajectory of a plurality of emission beams after passing through a plurality of scanning surfaces according to an embodiment of the present application;

[0081] FIG. 11 is a schematic diagram of a plurality of pointing angles of a plurality of emission beams according to an embodiment of the present application;

[0082] FIG. 12 is a schematic diagram of a scanning trajectory of a plurality of emission beams after passing through a plurality of scanning surfaces according to an embodiment of the present application;

[0083] FIG. 13 is a schematic diagram of a plurality of pointing angles of a plurality of emission beams according to an embodiment of the present application;

[0084] FIG. 14 is a schematic diagram of a scanning trajectory of a plurality of emission beams after passing through a plurality of scanning surfaces according to an embodiment of the present application;

[0085] FIG. 15 is a schematic diagram of a structure of a detection device according to an embodiment of the present application;

[0086] FIG. 16 is a schematic diagram of a structure of a detection device according to an embodiment of the present application;

[0087] FIG. 17 is a schematic diagram of an optical path of an optical loopback device according to an embodiment of the present application;

[0088] FIG. 18 is a schematic diagram of an optical path of an optical loopback device according to an embodiment of the present application;

[0089] FIG. 19 is a schematic diagram of an optical path of an optical loopback device according to an embodiment of the present application;

[0090] FIG. 20 is a schematic diagram of an optical switch tree according to an embodiment of the present application;

[0091] FIG. 21 is a schematic diagram of a beam splitter tree according to an embodiment of the present application;

[0092] FIG. 22 is a schematic diagram of a structure of a transceiver module according to an embodiment of the present application;

[0093] FIG. 23 is a schematic diagram of a structure of a transceiver module according to an embodiment of the present application;

[0094] FIG. 24 is a schematic diagram of a laser radar according to an embodiment of the present application;

[0095] FIG. 25 is a schematic diagram of a vehicle including a laser radar according to an embodiment of the present application. DETAILED DESCRIPTION

[0096] For the convenience of understanding, the following illustrates some concepts related to the embodiments of the present application for reference.

[0097] The detection device is a device for detecting a target in an object space. The working principle of the detection device is to emit a detection signal to the object space, receive a return signal from the object space, and obtain relevant information of the target in the object space according to the return signal, such as one or more of the distance, position, angle, speed, reflectivity, reflection intensity, color, or material of the target. The detection signal is usually an electromagnetic wave or a sound wave. The electromagnetic wave includes light, millimeter wave, or centimeter wave. The detection device provided in the embodiments of the present application takes light as the detection signal.

[0098] The subtense angle is used herein to describe the angle difference between each reflecting surface of the rotating mirror and the rotating shaft (or the cross section of the rotating shaft). For example, the rotating mirror includes four reflecting surfaces, and the included angles between the four reflecting surfaces and the rotating shaft of the rotating mirror are distributed in accordance with a first angle, and the subtense angle of the rotating mirror is the first angle.

[0099] Polarization refers to the vibration direction of the electric vector of light having a certain rule. Polarization is a property of light, and the polarization state is a parameter of light. The polarization state can be divided into linear polarization, elliptical polarization (including circular polarization), and the like. For example, for linearly polarized light, the electric vector vibrates back and forth along a direction. Non-polarized light, such as natural light, has a random vibration of the electric vector, neither in the same direction nor having a fixed time correspondence (no fixed phase) when vibrating, so the vibration is random and has no fixed rule.

[0100] A polarization beam splitter is an optical filter. The transmittance of signal light passing through the polarization beam splitter is related to the polarization direction of the signal light. Generally, linearly polarized light in a certain polarization direction can pass through, while light in some polarization directions is blocked (cannot pass through). In some scenarios, the polarization state of light is described by P-polarized light (hereinafter referred to as P light) and S-polarized light (hereinafter referred to as S light) when the light passes through the polarization beam splitter. Among them, P light represents linearly polarized light whose polarization direction is parallel to the polarization direction of the polarization beam splitter, and S light represents linearly polarized light whose polarization direction is perpendicular to the polarization direction of the polarization beam splitter. In other scenarios, the polarization state of light is also described by transverse electric (TE) or transverse magnetic (TM). TE-polarized light can pass through the polarization beam splitter when it passes through the polarization beam splitter, and the transmitted signal light still maintains TE polarization. TE polarization can be converted into circularly polarized light or elliptically polarized light after passing through a quarter wave plate (QWP) once. The circularly polarized light or elliptically polarized light is converted into TM-polarized light again after passing through the quarter wave plate. The TM-polarized light is reflected when it passes through the polarization beam splitter.

[0101] A waveguide is a structure used to direct electromagnetic waves, which can be transmitted between its endpoints. Light is also an electromagnetic wave, and a waveguide that transmits light is called an optical waveguide, such as a planar dielectric waveguide, or an optical fiber, etc.

[0102] A wave plate, also known as a phase retarder, can cause a phase shift between two mutually orthogonal polarization components of light passing through the wave plate, and can be used to adjust the polarization state of light. According to the phase shift of the wave plate, the wave plate can be divided into a half wave plate (HWP), a QWP, an eighth wave plate, etc. Optionally, the QWP shown in some embodiments of the present application can also be replaced by one or more of a Faraday rotator, a combination of a Faraday rotator and a wave plate, a combination of a quarter wave plate and a half wave plate, or a combination of two eighth wave plates, etc.

[0103] FMCW refers to an electromagnetic wave whose frequency changes over time. When the frequency of the electromagnetic wave changes linearly over time, it is called a linear frequency modulation continuous wave. Here, linear change generally refers to linear change within a transmission period. Exemplarily, the waveform of the linear frequency modulation continuous wave is generally a sawtooth wave or a triangular wave. Of course, FMCW can also have other possible waveforms, such as a linear frequency modulation step frequency waveform, etc.

[0104] A coherent detection device is a kind of detection device that uses a frequency-modulated continuous wave to detect a target. At the transmitting end, the coherent detection device generates a frequency-modulated continuous wave (light), part of which is transmitted to a mixer as a local oscillator beam, and part of which is transmitted into a field of view for detection. The frequency-modulated continuous light transmitted into the field of view is reflected by the target in the field of view to form a return wave. The return wave propagates back to the receiving end of the coherent detection device and is received as a receiving beam. The receiving beam is transmitted to the mixer and mixed with the local oscillator signal light to obtain an intermediate frequency signal. Processing the intermediate frequency signal can obtain information such as the relative distance, speed, angle, or reflectivity between the target and the relevant laser radar, and the detection precision is usually high.

[0105] The field of view refers to the range that can be detected by the detection device, also known as the field of view. In some scenarios, the transmitting end of the detection device and the target object, and / or the receiving end of the detection device and the target object, need to have a line of sight (LOS) area in which the signal (such as radio waves or laser) transmission is uninterrupted. This line of sight area can be understood as the field of view.

[0106] In recent years, intelligent driving technology has become one of the indispensable technologies in the process of vehicle driving, and is also a key technology in the development of vehicle intelligence. In the intelligent driving technology, the sensing layer is regarded as the "eyes" of the car, including visual system sensors such as vehicle-mounted cameras and radar system sensors such as vehicle-mounted millimeter wave radars, vehicle-mounted laser radars and vehicle-mounted ultrasonic radars. Among them, the laser radar can accurately measure the distance and position of the target and is widely used in intelligent vehicles. However, due to the limitations of power consumption, beam divergence angle and other factors, the resolution of the laser radar, especially the vertical resolution, has a lot of room for improvement.

[0107] Therefore, the application provides a detection device, a laser radar and a terminal, which can combine a multi-channel transmitting beam and a rotating mirror with a tower difference to realize encrypted scanning and uniform scanning, thereby significantly improving the resolution of the detection device. In addition, by combining the rotating mirror to realize encrypted scanning and uniform scanning, the manufacturing cost of the detection device will not increase significantly, and it is beneficial to realize the low-power design and miniaturization design of the detection device.

[0108] First, the detection device provided by the application will be introduced. Please refer to FIG. 1, which is a structural schematic diagram of a detection device provided by an embodiment of the application. The detection device 10 includes a transceiver module 11 and a rotating mirror 12. Among them:

[0109] The rotating mirror 12 includes M reflecting surfaces, and M is an integer and M≥2. In the embodiment of the application, the rotating mirror 12 has a tower difference with an angle α (also called a first angle for easy distinction), and the angles between the M reflecting surfaces and the cross section of the rotating mirror are distributed in an arithmetic progression with an angle difference of angle α, wherein the cross section can be a plane perpendicular to the activity axis (for easy description, it is called a first plane below).

[0110] Exemplarily, in combination with FIG. 1, taking the example that the M reflecting surfaces include reflecting surfaces R1 to R5, R1 to R5 are arranged around, R1 is adjacent to R2 and R5, R2 is adjacent to R1 and R3, and so on. The angles of R1 to R5 and the first plane can include the following five angles: β-2α, β-α, β, β+α, β+2α. Among them, β represents a certain angle, which can be set according to the actual situation, for example, β can be 90°. Of course, the application does not limit which angle each of the reflecting surfaces R1 to R5 actually corresponds to. For example, the angle of the reflecting surface R1 and the first plane can be β-2α, while the reflecting surface R1 can be any one of β-α, β, β+α and β+2α. It should be understood that the five-face rotating mirror shown in FIG. 1 is only an example, and other numbers of faces can be used in the specific implementation process, and the structure of the rotating mirror can also have other designs.

[0111] Exemplarily, as shown in (a) of FIG. 2, a four-mirror galvanometer includes reflecting surfaces R1 to R4, and the four-mirror galvanometer can rotate around an active axis. (b) of FIG. 2 is a cross-sectional view of the four-mirror galvanometer along the AA' line, and the plane P is a cross section of the four-mirror galvanometer, which is perpendicular to the active axis, the angle between the reflecting surface R3 and the plane P is 90°-2α, and the angle between the reflecting surface R1 and the plane P is 90°. Similarly, as shown in (c) of FIG. 2, the angle between the reflecting surface R4 and the plane P is 90°+α, and the angle between the reflecting surface R2 and the plane P is 90°-α. As shown in FIG. 2, the angles between the four reflecting surfaces of the galvanometer and the cross section are distributed in an arithmetic progression with an angle difference of α.

[0112] The transceiver module 11 includes at least N transceiver ports 1101, where N is an integer and N≥4. The transceiver module 11 is configured to generate N transmission beams, which are transmitted through the at least N transceiver ports 1101. The N transmission beams have different pointing angles. For example, as shown in FIG. 3, when N is 8, the eight transmission beams are denoted as #1 to #8, and the eight transmission beams have different pointing angles. Alternatively, the difference herein means that the pointing angles of at least two of the N transmission beams are different. Alternatively, the difference herein means that the pointing angles of the N transmission beams are all different. The embodiments of the present application are described by taking the case that the pointing angles of the N transmission beams are all different as an example, and the present application is also applicable to the case that the pointing angles of some of the N transmission beams are the same.

[0113] In some embodiments, as shown in FIG. 4, the detection device 10 further includes a lens 13, which is arranged in the transmission path of the transceiver ports 1101, for example, the lens 13 is arranged between the N transceiver ports 1101 and the galvanometer 12. The pointing angle of the beam is related to the position of the transceiver port 1101 relative to the lens 13. As a possible implementation, the included angle θ between the pointing angles of two of the N transmission beams is related to the spacing d between the transceiver ports corresponding to the two transmission beams and the focal length f of the lens. Exemplarily, as shown in FIG. 4, the included angle θ between the pointing angles satisfies the following relationship:

[0114] In the embodiments of the present application, the N transmitting beams are reflected to the object space by the rotating mirror 12. Due to the different angles between the M reflecting surfaces and the cross section of the rotating mirror, there is an angle deviation between the scanning tracks of the N transmitting beams after being reflected by different reflecting surfaces, which is equivalent to multiple scanning of a certain area. In combination with FIG. 5, taking the 8 transmitting beams, the rotating mirror with five reflecting surfaces and the tower difference α of 0.7 as an example, as shown in FIG. 5(a) and FIG. 5(b), the angle difference between the reflecting surface R1 and the reflecting surface R2 and the cross section of the rotating mirror is α, so the scanning track (taking the scanning line as an example) formed by the 8 transmitting beams after being reflected by the reflecting surface R1 has an α deviation from the scanning track formed by the 8 transmitting beams after being reflected by the reflecting surface R2. For example, along the arrangement direction of the N transmitting beams, the azimuth angle of the transmitting beam #1 after being reflected by the reflecting surface R1 is 10.8°, and the azimuth angle of the transmitting beam #1 after being reflected by the reflecting surface R2 is 10.1°, and the remaining transmitting beams are similar. Similarly, FIG. 5(c) shows the scanning track after being reflected by the reflecting surface R3, FIG. 5(d) shows the scanning track after being reflected by the reflecting surface R4, and FIG. 5(e) shows the scanning track after being reflected by the reflecting surface R5. After the N transmitting beams are reflected by the M reflecting surfaces, the corresponding detection area is scanned by the N transmitting beams for M times, and the M scanning is uniformly spaced by the angle α.

[0115] Please refer to FIG. 6, which is a schematic diagram of the scanning tracks formed after the M reflecting surfaces respectively reflect the N transmitting beams. After M scanning, the total number of lines transmitted by the detection device is M×N, which greatly improves the scanning density and can significantly improve the resolution of the detection device.

[0116] In some scenarios, the M×N beams are arranged along the direction perpendicular to the horizontal plane, which can be the bottom surface of the laser radar where the detection device is located. In this scenario, the scheme of the present application can significantly improve the vertical resolution of the detection device.

[0117] In some scenarios, the rotating mirror is continuously rotating, and the time periods for the M reflecting surfaces to reflect the N transmitting beams are different. That is, the M reflecting surfaces are movable around the activity axis, and the N transmitting beams are scanned to the object space in different time periods. The scanning tracks of the N transmitting beams after being reflected by the M reflecting surfaces are M×N scanning lines. In addition, by means of time division, M times of scanning is realized by combining the N transmitting beams with the M reflecting surfaces with different angles, which can ensure the power of the transmitted beams during each scanning and improve the detection accuracy.

[0118] In some possible embodiments, the included angle of the pointing angles of the beams can be designed to meet different resolution requirements. In one aspect, in the N beams, when the included angle between two beams is relatively large, the distribution of the scanning lines formed after being reflected by the M reflecting surfaces is relatively sparse. Conversely, when the included angle between two beams is relatively small, the distribution of the scanning lines formed after being reflected by the M reflecting surfaces is relatively dense. In another aspect, the distribution of the scanning lines is also affected by the tower difference α. The smaller the angle difference between two reflecting surfaces is, the smaller the deviation of the scanning tracks of the beams passing through the two reflecting surfaces is, and thus a denser scanning line distribution can be designed.

[0119] In summary, the manufacturer, the developer, or the host factory can design different angles of the beams and tower differences according to requirements to meet different resolution requirements. Even multiple included angles can be designed in the beams, as shown in FIG. 3, to form multiple areas with different resolutions in the field of view to meet specific resolution requirements.

[0120] The following exemplary describes several possible resolution designs, which are achieved by designing the included angles between the beams. In specific examples, the following angle designs can be combined with different numbers of reflecting surfaces and tower differences to achieve multiple resolution distributions.

[0121] Design 1: The N beams include a first beam and a second beam adjacent to the first beam, and the included angle of the pointing angles of the first beam and the second beam is a second angle x, and the following relationship exists between the first angle α and the second angle x: x = M x α. In combination with FIG. 3, in an example in which the first angle α is 0.7 and M is 5, the first beam can be beam #1 and beam #2, and the included angle of the pointing angles of beam #1 and beam #2 is (5 x 0.7° =) 3.5°.

[0122] In combination with FIG. 6, after the beam #1 undergoes M scans, the scanning tracks (i.e., M scanning lines) of the beam #1 are shown in the scanning line group G1 shown in FIG. 6, and similarly, the M scanning lines formed after the beam #2 undergoes M scans are the scanning line group G2. Due to the design of the angles, the tower difference, and the number of scanning surfaces of the beam #1 and the beam #2, the scanning line group G1 and the scanning line group G2 do not overlap with each other, and the angular interval (the interval c1 shown in FIG. 6) between the two is the first angle α. In combination with FIG. 6, it can be known that the 2 x M scanning lines formed after the beam #1 and the beam #2 undergo the M reflecting surfaces are uniformly distributed at the interval of the first angle α, and the distribution of the scanning lines in the detection area (or the field of view) corresponding to the beam #1 is uniform. In this way, the uniformity of scanning can be improved, the detection resources of the detection device are reasonably allocated, and the detection efficiency is improved.

[0123] It should be understood that one or more groups of N emission beams can be designed, and even the design shown in design 1 can be satisfied between N emission beams. In combination with FIG. 3, in the case of 8 emission beams, the angle satisfying the above-mentioned relationship can also be designed between beam #2 and beam #3, and between beam #7 and beam #8. The present application does not limit the number of groups of beams in which the above-mentioned angle relationship exists among N emission beams.

[0124] Design 2, N emission beams include K third beams adjacent to each other, and the included angle of the pointing angle between any two adjacent beams among the K third beams is a third angle y1. The third angle y1 is related to the first angle a.

[0125] As a possible implementation, the third angle y1 satisfies the following relationship:

[0126] y1*K = a,

[0127] Wherein, K is a positive integer, such as 2, 3, 4, etc. In combination with FIG. 3, in the case of the first angle a being 0.7° and K being 2, the K third beams include beam #3 and beam #4, and the included angle of the pointing angle of beam #3 and beam #4 is (0.7° ÷ 2 =) 0.35°.

[0128] Taking the reflecting surface R1 and the reflecting surface R2 as an example, the included angle between the reflecting surface R1 and the first plane is β, and the included angle between the reflecting surface R2 and the first plane is β + a. For the same emission beam, there is an angle deviation of a between the scanning tracks formed after respectively experiencing the reflecting surface R1 and the reflecting surface R2. At this time, if the K emission beams are designed as a group, then after experiencing the reflecting surface R1 and the reflecting surface R2 once, the scanning lines formed by the K emission beams can be uniformly distributed within the angle deviation a formed by twice scanning. By analogy, after M scanning surfaces are scanned respectively, the scanning lines formed by the K emission beams are uniformly distributed, so that encrypted scanning and uniform scanning can be realized.

[0129] In combination with FIG. 6, after the K third beams pass through the M reflecting surfaces, the scanning tracks (i.e. M scanning lines) are as shown in the scanning line group G3 (conveniently referred to as the first scanning line group) shown in FIG. 6. The K*M scanning lines in the scanning line group G3 are uniformly distributed at intervals of the third angle y1.

[0130] In the above implementation, the value of K affects the resolution multiple of the detection area corresponding to the K third beams. In the embodiment shown in FIG. 3, K = 2 is taken as an example. In the specific implementation process, K can be designed as other values to meet different resolution requirements. Referring to (a) of FIG. 7, in the case of K = 3, the K third beams are beam #l1, beam #l2 and beam #l3. Among beam #l1, beam #l2 and beam #l3, the included angle of the pointing angle between any two adjacent beams is the first angle a. As shown in Fig. 7(b), the scanning lines formed by the K transmitting beams can be evenly distributed within the angle deviation a, and the 3xM scanning lines in the first scanning line group are arranged in turn with an interval of Compared with the design 1, the design 2 can improve the resolution by 2 times.

[0131] In some possible implementation, in combination with the design 2, the N transmitting beams further include a fourth beam, the K third beams and the fourth beam are arranged in turn and adjacent to each other, an included angle between the fourth beam and a fifth beam is a fourth angle z1, the fifth beam is the third beam closest to the fourth beam, and the fourth angle z1 satisfies the following relationship:

[0132] z1+q=Mx a.

[0133] wherein q is a real number of 0. The above relationship can be replaced by other expressions, for example, the fourth angle z1 satisfies the following relationship:

[0134] z1=Mx a-q.

[0135] In the foregoing implementation, the value of q affects the gap between the scanning tracks formed by the K third beams and the scanning track formed by the fourth beam, and the gap is (a-q). Further, q≠a. In this way, when the fourth angle z1 satisfies the foregoing relationship, the scanning tracks formed by the K third beams and the scanning track formed by the fourth beam can not overlap each other after being reflected by the M reflecting surfaces, and the scanning tracks formed by the K third beams and the scanning track formed by the third beam have a gap, i.e., (a-q)≠0.

[0136] Further, q=(K-1)y1, that is, the fourth angle z1 satisfies the following relationship:

[0137] z1+(K-1)y1=Mx a.

[0138] Since y1*K= a, in the case of q= (K-1)y1, the scanning trajectory of the K third beams and the scanning trajectory formed by the third beams can have a gap of y1, thereby further improving the uniformity of the scanning. In combination with (a) of FIG. 7, beam #l1, beam #l2 and beam #l3 are the K third beams, beam #l4 is the fourth beam, and the beam closest to beam #l4 among the K third beams is beam #l3, that is, the included angle between beam #l3 and beam #l4 is the fourth angle z1. As shown in (b) of FIG. 7, taking M=5 as an example, the K*M scanning lines formed by the K third beams after passing through the M reflecting surfaces are the first scanning line group, and the M scanning lines formed by the fourth beam (beam #l4) after passing through the M reflecting surfaces are the second scanning line group. The first scanning line group and the second scanning line group do not overlap, and the angle interval between the edge of the first scanning line group close to the second scanning line group and the edge of the second scanning line group close to the first scanning group is the third angle y1, which is consistent with the gap of the scanning lines in the first scanning line group. In this way, the uniformity of the scanning line distribution can be further improved, and the proportion of the high-resolution region is increased.

[0139] Similarly, in combination with FIG. 3, beam #3 and beam #4 can be regarded as K third beams (K=2), and beam #5 can be regarded as a fourth beam. Similarly, beam #5 and beam #6 can be regarded as K third beams (K=2), and beam #7 can be regarded as a fourth beam.

[0140] Design 3, the N transmitting beams include J sixth beams and a seventh beam in turn, and the included angle of the pointing angle between any two adjacent beams among the J sixth beams is a fifth angle y2. The fifth angle y2 satisfies the following relationship:

[0141] y2*J= a,

[0142] wherein J is an integer and J>1. The included angle between the seventh beam and an eighth beam is a sixth angle z2, and the eighth beam is the beam closest to the seventh beam among the J sixth beams. The sixth angle z2 and the fifth angle y2 satisfy the following relationship:

[0143] z2= M* a.

[0144] In comparison with the aforementioned relationship z1+q= M* a, it can be seen that the above relationship z2= M* a is a variant of the case of q=0. As shown in (a) of FIG. 8, beam #l1, beam #l2 and beam #l3 are the J sixth beams, beam #l4 is the eighth beam, and the beam closest to beam #l4 among the J sixth beams is beam #l3, that is, the included angle between beam #l3 and beam #l4 is the sixth angle z2. As shown in (b) of FIG. 8, in the case of the angle design of design 3, the scanning trajectory of the J sixth beams (the third scanning line group shown in FIG. 8) and the scanning trajectory formed by the eighth beam (the fourth scanning line group) have a gap, and the gap is a.

[0145] Design 4, the N emission beams include a ninth beam and a tenth beam, the included angle of the pointing angles of the ninth beam and the tenth beam is a seventh angle y3. The seventh angle y3 satisfies the following relationship:

[0146] y3*L=M* a.

[0147] Wherein, K is an integer and K≥2, thus, after being reflected by the M reflecting surfaces, the scanning trajectories of the ninth beam and the tenth beam are interlaced, and a high resolution can be achieved in the interlaced area.

[0148] In a possible implementation, L and K≥2. Referring to (a) of FIG. 9, the beam #l5 can be regarded as the ninth beam, and the beam #l6 can be regarded as the tenth beam. Referring to (b) of FIG. 9, the M scanning lines formed by the beam #l5 after passing through the M reflecting surfaces are the fifth scanning line group, and the M scanning lines formed by the beam #l6 after passing through the M reflecting surfaces are the sixth scanning line group. It can be seen that the half of the fifth scanning line group close to the sixth scanning line group is interlaced with the half of the sixth scanning line group close to the fifth scanning line group, and the scanning lines in the interlaced part of the fifth scanning line group and the sixth scanning line group are uniformly distributed at intervals of a / 2. In this way, the uniformity of the scanning line distribution can be further improved, and the resolution of the detection device can be improved.

[0149] Further, a plurality of emission beams in the N emission beams can be designed to satisfy the angle relationship of design 4, and the plurality of emission beams can be adjacent in turn, so as to overlap in turn, thereby forming a high-resolution area with a larger range. Referring to (a) of FIG. 10, the beam #l5, the beam #l6 and the beam #l7 are adjacent in turn, and the included angle between any two adjacent emission beams is (M* a) / L, and L=2. Referring to (b) of FIG. 10, the M scanning lines formed by the beam #l5 after passing through the M reflecting surfaces are the fifth scanning line group, the M scanning lines formed by the beam #l6 after passing through the M reflecting surfaces are the sixth scanning line group, and the M scanning lines formed by the beam #l7 after passing through the M reflecting surfaces are the seventh scanning line group. Half of the sixth scanning line group is interlaced with the fifth scanning line group, and the other half is interlaced with the seventh scanning line group. In the interlaced area, the intervals between the scanning lines are a / 2, and the resolution of the interlaced area is further improved.

[0150] It should be understood that in a specific implementation, more angle designs can be implemented according to the resolution requirement, and the above angle designs are only examples.

[0151] It should be noted that the above four designs can be combined, for example, a plurality of groups of beams satisfying the angle of design 1 can be designed in the N emission beams, and a plurality of groups of beams satisfying the angle of design 2 (or a possible implementation of design 2) can be designed. The following introduces several possible implementations:

[0152] In a possible implementation, the second angle x is the maximum of the angles between adjacent beams of the N beams. As shown in FIG. 3, in the example where the first angle a is 0.7 and M is 5, the angle between beam #1 and beam #2, i.e., the second angle x, is the maximum of the angles between adjacent beams of the N beams. The angles between the remaining beams are all less than or equal to the second angle x. In this way, the maximum angular interval between the scanning lines of the M*N scanning lines is the first angle a, which ensures the resolution of the detection device.

[0153] In a possible implementation, when the N beams include beams (or beam groups) satisfying the angle of design 1 and beams (or beam groups) satisfying the angle of design 2, the beams satisfying the angle of design 1 are designed to be close to the edge region, and the beams satisfying the angle of design 2 are designed to be away from the edge region. That is, the angle formed by the first beam and the second beam is closer to the edge of the N beams than the angle formed by the K third beams.

[0154] For example, in combination with FIG. 3, beam #1 and beam #2 are beams satisfying the angle of design 1, and beam #3 and beam #4 are beams satisfying the angle of design 2. At this time, the angle formed by beam #1 and beam #2 is closer to the edge of the N beams, and the angle formed by beam #3 and beam #4 is closer to the center of the N beams. In this way, in the field of view formed after scanning the N beams, the scanning line interval is larger in the edge region and smaller in the middle region, thereby facilitating the scanning of the middle region of the field of view, and the resolution of the middle region is K times that of the edge region.

[0155] In some scenarios, improving the detection accuracy of the middle region can effectively improve the value of the detection result and be beneficial to the calculation and decision related to the perception result. For example, the present application can be applied in vehicle perception, intelligent driving, surveying and mapping, robot perception and the like. For example, in the vehicle perception scenario, the central region of the field of view usually includes the space where the vehicle is most likely to travel, which is a high-value field of view, i.e., a region of interest (ROI). Through the scheme of the present application, the detection accuracy of the ROI can be improved, thereby improving the driving safety of the vehicle. Especially for the intelligent driving system, the higher the detection accuracy of the ROI, the more beneficial to the calculation and decision of the intelligent driving system, thereby improving the safety and comfort of the intelligent driving system.

[0156] Similarly, when the N beams include beams satisfying the angle of design 1 and beams satisfying the angle of design 3, the beams satisfying the angle of design 1 are designed to be close to the edge region, and the beams satisfying the angle of design 3 are designed to be away from the edge region.

[0157] Similarly, when the N transmitting beams include beams satisfying the angle of design 1 and beams satisfying the angle of design 4, the beam design satisfying the angle of design 1 is designed in the area close to the edge, and the beam design satisfying the angle of design 4 is designed in the area away from the edge.

[0158] The foregoing introduces a plurality of angle designs, and some possible implementations. The following exemplary introduces three possible beam angle design examples:

[0159] Example 1, see FIG. 3, N transmitting beams include beams #1 to #8, taking M=5 and a=0.7 as an example, the angles formed between beam #1, beam #2 and beam #3 are located in the edge area, and the angles between the two of the three transmitting beams comply with the description of design 1. While beam #3, beam #4 and beam #5 are a possible implementation of design 2, and beam #5, beam #6 and beam #7 are also a possible implementation of design 2. The above-mentioned beams #3 to #6 form an angle in the middle area. Finally, the angles formed by beam #7 and beam #8 are located in the edge area, and the angle design of the two transmitting beams complies with the description of design 1.

[0160] As can be seen from FIG. 6, the N transmitting beams combined with the tower difference of the rotating mirror can be regarded as NXM transmitting beams during detection, achieving M times of encryption detection. On this basis, multiple encryption of the ROI area can be formed, for example, the area corresponding to the middle scan line groups G3 and G4 can be regarded as ROI, and the scan line groups G1, G2, G5 and G6 can be regarded as non-ROI area. Therefore, through the angle design, combined with the tower difference of the reflecting surface and the rotating mirror, the density of the scan lines in the ROI area can be higher than that of the scan lines in the non-ROI area, so that the resolution of the ROI area is improved by one time, or even multiple times, compared with the non-ROI area. Improving the resolution of the ROI area can improve the usability of the detection results output by the detection device, and is conducive to the accuracy and usability of subsequent calculation and decision-making based on the detection results.

[0161] Example 2, refer to FIG. 11, N transmit beams include beams #1 to #8, take M=5, a=0.7 as an example, the difference between FIG. 11 and FIG. 3 is that the angle between beam #6 and beam #7 is 3.5°, therefore, the angle design of beam #5, beam #6 and beam #7 satisfies the aforementioned design 3. The scanning tracks formed by the 8 transmit beams shown in FIG. 11 after passing through M reflectors are shown in FIG. 12, the difference between FIG. 12 and FIG. 6 is that in FIG. 6, the interval between scan line group G4 (the scanning track formed by beam #5 and beam #6) and beam G6 (the scanning track formed by beam 7) is a / 2, while in FIG. 12, the interval between scan line group G4 (the scanning track formed by beam #5 and beam #6) and beam G6 (the scanning track formed by beam 7) is a. Therefore, FIG. 12 can achieve a larger vertical field of view angle (20.65°), which is increased by 0.35° compared with 20.3° of FIG. 6. However, in combination with FIG. 6, the beam design shown in FIG. 3 will make the angle of the high-resolution region (for example, as ROI) be 7°, while the beam design shown in FIG. 12 makes the angle of the high-resolution region (for example, as ROI) be 6.65°, therefore, the possible implementation of design 2 can obtain a larger high-resolution region.

[0162] Example 3, refer to FIG. 13, N transmit beams include beams #1 to #8, take M=5, a=0.7 as an example. The difference between FIG. 13 and FIG. 3 is that the angle design of beams #3 to #6 satisfies the aforementioned design 4. The scanning tracks formed by the 8 transmit beams shown in FIG. 13 after passing through M reflectors are shown in FIG. 14, the vertical field of view angle is 20.3°, among which 8.4° above the field of view is a normal encryption region, which is uniformly scanned, 7° in the middle of the field of view is a doubled encryption region, which is also uniformly scanned, and 4.9° below the field of view is also a normal encryption region. It can be seen that the example shown in FIG. 3 can also achieve multiple encryption of the ROI region (such as 7° in the middle of the field of view), the resolution of the ROI region is doubled compared with the non-ROI region, which can improve the usability of the detection result output by the detection device, and is conducive to the accuracy and usability when subsequent calculation and decision are made based on the detection result.

[0163] It should be understood that the foregoing designs, implementations and examples are exemplary descriptions made for the purpose of facilitating understanding of the scheme of the present application, and the number of beams, specific values of the included angles, the number of reflectors, the tower difference, the angle range of the ROI region, the angle range of the non-ROI region and the like described in the foregoing are only examples, and in the specific implementation process, the present application is also applicable to the case of taking other values for the foregoing parameters.

[0164] The angle design of the beams is described above, and some possible implementations of the present application are further described below. It should be understood that the various embodiments described in the present application can be combined.

[0165] As a possible implementation, each of the N transmitting beams comprises FMCW. The frequency of the FMCW varies over time, and the variation law comprises one or more of sawtooth, triangle, or sine, etc. Using the FMCW detection device, the laser is modulated, and the time-varying frequency information is marked on the transmitted beam. After the beam is transmitted and reflected on the object surface, it is received by the receiving end. By comparing the frequency characteristics of the received beam with the frequency characteristics of the local oscillator signal, the relevant information of the target can be obtained, and the detection accuracy is high.

[0166] Since the change of the frequency characteristics often needs a certain time length to reflect, it leads to that the measurement time is often longer when using the coherent radar to measure, and the number of target points obtained is less, and the resolution is low. The present application can encrypt and uniformly scan the detection area, can improve the resolution of the FMCW laser radar, and thus significantly improve the detection accuracy of the FMCW.

[0167] As a possible implementation, the transceiver module further comprises at least one laser group, each laser group comprising a laser for generating a light beam. That is, the transceiver module can comprise one or more lasers. Optionally, the transceiver module comprises a laser that can emit FMCW.

[0168] Please refer to FIG. 15, the transceiver module 11 of the detection device 10 comprises lasers 112 and 113 for generating light beams. Optionally, the light beams from the lasers are processed (for example, through the optical processing module 1104) and then emitted from at least N transceiver ports 1101 to form N transmitting beams.

[0169] As a possible implementation, each of the N transmitting beams comprises light beams from at least two lasers. Further, in the light beams from the at least two lasers, the properties of the light beams from any two lasers are not completely the same, that is, at least one attribute is different. Exemplarily, the light beams from any two lasers are different in at least one of the sweep slope, frequency, and wavelength. By using two lasers with different properties of the light beams, after receiving the returned light beams, the local oscillator signals corresponding to each laser can be mixed in the mixing stage, the number of target points obtained (i.e., the out-point rate is improved) is increased, and the detection accuracy is improved.

[0170] In combination with FIG. 15, the transceiver module 11 of the detection device 10 includes a laser 112 and a laser 113, in which the sweep modulation waveforms of the laser 112 and the laser 113 can be different forms, for example, both the laser 112 and the laser 113 use a triangular wave. One period of the triangular wave includes two half periods, and the sweep slopes of the two half periods include a positive slope and a negative slope. In the first half period, the laser 112 is swept modulated at the positive slope, and the laser 113 is swept modulated at the negative slope, while in the second half period, the laser 112 is swept modulated at the negative slope, and the laser 113 is swept modulated at the positive slope. After the respective processing of the received echoes corresponding to the two lasers, the respective target-related information (such as speed and distance information) of the targets can be obtained. In the same time, the laser radar using the two lasers as light sources has a higher out-point rate, and a higher out-point rate can be achieved by measuring the overlap between the points.

[0171] Of course, the above embodiment is a possible case, and the present application is also applicable to the case where each transmission beam includes only a light beam from one laser.

[0172] As a possible embodiment, the transceiver module is further configured to receive N reception beams. Further, the N reception beams include echoes corresponding to the N transmission beams. In some implementations, the N reception beams are received through reception ports, such as the reception ports 1012 of the transceiver module 11 in FIG. 15. In other implementations, the transceiver ports 1011 can both transmit light beams and receive light beams, so the N reception beams can be received through the at least N transceiver ports 1101.

[0173] As a possible embodiment, the transceiver module further includes a plurality of mixers, each of the plurality of mixers corresponding to at least one of the N transmission (Tx) beams and at least one of the N reception (Rx) beams. Each of the plurality of mixers is configured to mix a local oscillator (LO) beam of the corresponding at least one of the Tx beams and the corresponding at least one of the Rx beams to obtain a mixing result. Optionally, the mixer is a 90° mixer or a 180° mixer.

[0174] In combination with FIG. 15, in the detection device 10, the transceiver module 11 includes a plurality of mixers 1013, each of which corresponds to one of the N Tx beams and one of the N Rx beams. For example, the mixer 1 corresponds to Tx1 and Rx1, and is configured to mix a local oscillator (LO1) of Tx1 and Rx1 to obtain a mixing result.

[0175] It should be understood that the foregoing FIG. 15 illustrates the receiving of the receiving line bundle using the receiving port as an example. In some possible implementations, the N receiving line bundles are received by the transceiving port 1011. Referring to FIG. 16, the difference between the embodiment shown in FIG. 15 is that the at least N transceiving ports 1101 are also used to receive the N receiving line bundles, and the N receiving line bundles are provided to the corresponding mixers via the optical loopback device. In addition, it should be noted that the number of lasers, the number of transmission channels, the number of receiving channels, the number of transceiving ports, and the like shown in FIGS. 15 and 16 are only examples.

[0176] As a possible implementation, the transceiving module includes N transceiving ports and N mixers, and the N transceiving ports and the N mixers are arranged alternately along the arrangement direction of the N transceiving ports. As shown in FIGS. 15 and 16, one transceiving port is arranged between two mixers, so that the two mixers are not arranged adjacently. Since the mixers need to receive the local oscillator signal and the receiving line bundle received by the transceiving port, the arrangement of the N transceiving ports and the N mixers alternately can reduce the intersection points of the optical paths, reduce the noise floor of the optical beams, and improve the detection accuracy.

[0177] Optionally, taking the mixer as a 90° mixer as an example, in the case where the transmission line bundle includes optical beams from multiple lasers, the echo signal and the local oscillator signal both contain signals of two lasers, and the 90° mixer can distinguish the related information (for example, distance and speed information) of the target through complex signal processing. In other embodiments, the echo corresponding to each laser can also be separated from the echo signal, and mixed with the local oscillator signal corresponding to each laser. The separation method here can be wavelength beam splitting or energy beam splitting.

[0178] As a possible implementation, the detection device further includes a detector, and the detector includes a germanium-silicon detector or a III-V group detector, for example. Further, the mixer can be connected to the detector, and the mixing result of the mixer can be output to the detector, and the detection result of the field of view can be obtained by processing the mixing result by the detector.

[0179] As mentioned above, in the case where the transceiving port is used for both transmission and reception, an optical loopback device needs to be arranged in the detection device to separate the optical paths of the transmission line bundle and the receiving line bundle, so as to realize the coaxial transmission and reception. The optical loopback device can be referred to as a polarization multiplexer, including PBS, PRS, PBRS, PBSR, and the like. The optical loopback device has at least three ports, which can distinguish the transmission line bundle and the receiving line bundle through polarization multiplexing. Two possible optical loopback devices will be introduced below with reference to FIGS. 17 and 18.

[0180] Referring to FIG. 17, it is a possible optical loopback device, which is configured to input a transmit beam through port 1 in TE polarization direction and output the transmit beam through port 2 in TE polarization direction. A receive beam is input through port 2 in TM polarization direction, converted to TE polarization direction in the optical loopback device, and output through port 3. The port 3 is connectable to a mixer so that the receive beam is mixed with a local oscillator beam in TE polarization direction. At this time, the polarization direction of the mixer is TE direction.

[0181] Referring to FIG. 18, it is another possible optical loopback device, which is configured to input a transmit beam through port 1 in TE polarization direction and output the transmit beam through port 2 in TE polarization direction. A receive beam is input through port 3 in TM polarization direction. The port 3 is connectable to a mixer, and further, a local oscillator beam in TE polarization direction is converted to TM polarization direction and mixed with the receive beam output through port 3. At this time, the polarization direction of the mixer is TM direction.

[0182] Referring to FIG. 19, it is another possible optical loopback device, which is configured to input a transmit beam through port 1 in TE polarization direction and output the transmit beam through port 2 in TE polarization direction. A receive beam is input through port 3 in TE polarization direction. The port 3 is connectable to a mixer, and further, a local oscillator beam in TE polarization direction is mixed with the receive beam output through port 3. At this time, the polarization direction of the mixer is TE direction.

[0183] As a possible implementation, the N transceiver ports are further configured to receive N receive beams, and the transceiver module further comprises a plurality of optical loopback devices. In combination with the aforementioned FIG. 17, FIG. 18 or FIG. 19, and the probe device shown in FIG. 16 (taking the optical loopback device as an example of PBRS), each of the plurality of optical loopback devices comprises a first port, a second port and a third port, the second port is connected to at least one of the transceiver ports, and the third port is connected to one of a plurality of mixers. The optical loopback device is configured to receive a to-be-transmitted beam from the first port and output the to-be-transmitted beam from the second port to exit from the corresponding transceiver port. The optical loopback device is further configured to obtain a receive beam provided by the corresponding transceiver port and output the receive beam from the third port to the corresponding mixer.

[0184] As a possible implementation, the transceiver module includes M transceiver ports, M is an integer and M>N. The plurality of optical loopback devices includes a first optical loopback device, as shown in FIG. 20, the second port (i.e. the port outputting the outgoing beam and inputting the incoming beam) of the first optical loopback device is connected to the root of the optical switch tree, and the leaf of the optical switch tree is connected to the plurality of transceiver ports. Taking an optical switch tree including 4 leaf nodes as an example, the leaf of the optical switch tree can be connected to 4 transceiver ports, which are respectively denoted as transceiver ports 1101a, 1101b, 1101c and 1101d. The optical switch tree includes a plurality of optical switches arranged in a tree structure, as shown in FIG. 20, 3 optical switches, i.e. optical switch 1, optical switch 2 and optical switch 3, are arranged in two layers, the output of the optical switch at the parent node is used as the input of the optical switch at the child node, for example, the optical switch 1 can select the optical path to the optical switch 2 or the optical path to the optical switch 3, and the optical switch 2 is used to select the optical path to the transceiver port 1101a or the optical path to the transceiver port 1101b.

[0185] The optical switch tree is used to select one of the transceiver ports, so that the outgoing beam from the second port of the first optical loopback device is emitted from the selected transceiver port. For example, the optical switch tree can select the optical path from the root to the transceiver port 1101a, so that the beam output by the first optical loopback device is emitted from the transceiver port 1101a, and the incoming beam from the transceiver port 1101a is received.

[0186] In the above implementation, by selecting any port through the optical switch tree, the position of the port emitting the beam can be adjusted. Accordingly, the distance between the ports emitting the two beams is also adjusted accordingly. Further, since the distance between the ports affects the pointing angle between the beams, the above implementation can adjust the pointing angle between the beams, and the pointing angle between the beams can be adjusted according to the requirements, so as to meet the resolution requirements in various scenarios and improve the application flexibility of the detection device.

[0187] Optionally, among the optical loopback devices included in the transceiver module 11, one or more optical loopback devices can be connected to the optical switch tree. For example, each optical loopback device is connected to the optical switch tree as shown in FIG. 20.

[0188] As a possible implementation, the transceiver module includes M transceiver ports, M is an integer and M>N. The N optical loopback devices include a second optical loopback device, as shown in FIG. 21, the second port of the second optical loopback device is connected to the root end of the splitter tree, and the leaf end of the splitter tree is connected to the plurality of transceiver ports. Taking an optical switch tree including 4 leaf nodes as an example, the leaf end of the splitter tree can be connected to 4 transceiver ports, which are respectively denoted as transceiver ports 1101e, 1101f, 1101g and 1101h. The splitter tree includes a plurality of splitters arranged in a tree structure, such as splitters s1, s2 and s3. The splitter tree is used to split the optical beams received from the root end into multiple paths and exit from the plurality of transceiver ports connected to the leaf end.

[0189] Optionally, among the optical loopback devices included in the transceiver module 11, one or more optical loopback devices can be connected to a splitter tree. For example, the optical loopback devices close to the edge of the transceiver module are connected to an optical switch tree as shown in FIG. 21.

[0190] As a possible implementation, the transceiver module includes a silicon optical chip, the silicon optical chip includes an entry port, at least N transceiver ports and an optical waveguide, the optical waveguide is used to transmit optical beams between components of the silicon optical chip. Among them, the components of the silicon optical chip include the entry port and the transceiver ports. Optionally, the silicon optical chip further includes a plurality of mixers and / or a plurality of optical loopback devices.

[0191] As a possible implementation, the silicon optical chip integrates a light source, a silicon optical chip, an optoelectronic conversion circuit and an optical device. The silicon optical chip contains a plurality of laser emission and reception channels, and can be coupled with H (H≥1) light source groups, each group of light sources contains one or two lasers, and the laser emitted by the light source forms N emission beams through the optical processing module (or optical distribution network). The reception beam and the emission beam are transmitted and received through the port on the silicon optical chip. In the transceiver coaxial architecture, the emission beam and the reception port are received through the transceiver port, and the coaxial architecture design can simplify the optical adjustment difficulty and reduce the number of optical devices. Of course, for off-axis architecture, some schemes of the present application are also applicable, and in the off-axis architecture, the emission beam and the reception beam use different ports for transmission / reception (as shown in FIG. 15).

[0192] Optionally, the material platform of the silicon optical chip has a variety of possible designs. Exemplarily, the material platform of the silicon optical chip can be an SOI silicon waveguide platform, a silicon nitride waveguide platform, a silicon oxynitride waveguide platform, or a silica PLC waveguide platform. Exemplarily, the material platform of the silicon optical chip can be a multi-layer waveguide platform with multiple types of waveguide layers stacked.

[0193] As a possible implementation, in the case that the transceiver module comprises a silicon photonic chip, the transceiver port in the silicon photonic chip is also called a transceiver coupler, which can be implemented by an edge coupler. Each transmitting beam is transmitted from the edge of the silicon photonic chip through a coupler, and each receiving beam is received from the edge of the silicon photonic chip through a coupler. Similarly, the incoming port, the receiving port (optional) are also implemented by edge couplers.

[0194] For ease of understanding, a possible structure of a silicon photonic chip for receiving beams from two lasers and processing to obtain four transmitting beams, and receiving four receiving beams and mixing and outputting to a detector respectively, is introduced below in combination with FIG. 22. As shown in FIG. 22, the silicon photonic chip comprises an incoming port (such as incoming port 1, incoming port 2), a beam splitter 1, a beam splitter 2, a beam combiner 1, a beam splitter tree 1, a feedback module, and four transceiver ports. The beam from laser 1 is coupled into the silicon photonic chip through the incoming port 1, and the beam from laser 2 is coupled into the silicon photonic chip through the incoming port 2. The beam splitter 1 splits the beam from the laser 1 into a beam a0 and a beam a1, and the beam splitter 2 splits the beam from the laser 2 into a beam b0 and a beam b1. The beam combiner 1 combines the beam a0 and the beam b0 to obtain a combined beam, and the beam splitter tree 1 splits the combined beam into a feedback beam (i.e., feedback 1), a plurality of beams to be transmitted (i.e., Tx1 to Tx4), and a plurality of local oscillator beams (i.e., LO1 to LO4), the plurality of beams to be transmitted are input into a plurality of optical loopback devices respectively, and the plurality of local oscillator beams are input into a plurality of mixers respectively, and the mixers further output the mixing results to a detector. The feedback module mixes the feedback beam with the beam a1 and the beam b1 respectively to obtain a feedback result, wherein the feedback beam has a longer transmission path than the beam a1 and the beam b1, and the path of the feedback beam can be regarded as a long arm, and the beam a1 and the beam b1 belong to a short arm. Further, the feedback result can be output to the detector.

[0195] Further, the aforementioned beam splitter 1, beam splitter 2, beam combiner 1, beam splitter tree 1, and feedback module can be regarded as a set of optical processing modules. In a specific implementation, the silicon photonic chip can comprise a plurality of optical processing modules to process a plurality of light sources, thereby increasing the transmitting beams and ensuring the transmission power of each transmitting beam. Alternatively, some modules in the plurality of optical processing modules can be shared, for example, some optical waveguides (i.e., some optical paths can be combined) or a feedback module.

[0196] As a possible implementation, no optical amplifier is provided in the silicon photonic chip, for example, no optical amplifier is provided in the silicon photonic chips shown in FIG. 22 and FIG. 23 below. In this way, the power consumption of the detection device can be reduced, and since the optical amplifier needs to be supported by a large current, not designing the optical amplifier can reduce the heat generated by the silicon photonic chip and improve the reliability of the silicon photonic chip.

[0197] In some schemes, since the application does not need to greatly increase the channel harness to improve the resolution, the transmission power of each transmission beam can meet the detection requirements, and the design of the optical amplifier will not cause a significant reduction in the transmission power.

[0198] Of course, the application is also applicable to the case where the optical amplifier is arranged in the silicon optical chip.

[0199] As a possible implementation, the plurality of to-be-transmitted light beams and the plurality of local light beams are arranged in a cross arrangement, as shown in FIG. 22. The Tx and LO are arranged in a cross arrangement, and no intersection point can be achieved between the plurality of Tx, LO and Rx. Since the local light beam needs to be mixed with the receiving beam corresponding to the transmission beam, the cross arrangement can reduce the intersection point of the optical path, reduce the noise level, and improve the detection accuracy of the detection device.

[0200] In order to facilitate understanding, a possible design of a transceiver module will be introduced below in combination with FIG. 23. Referring to FIG. 22, the transceiver module 11 includes a laser (taking an FMCW laser as an example), a beam combiner, a beam splitter (not shown), a mixer (represented by a black square), wherein the beam splitter is not shown by a device, but the position where the light beams branch in the figure is provided with a beam splitter. The entering port is arranged at the edge of the silicon optical chip close to the laser, and the transceiving port is represented by a triangle, and the optical loopback device is taken as PBRS for illustration.

[0201] As can be seen from FIG. 23, the transceiver module 11 can include two groups of lasers, laser 1 and laser 2 being one group, and laser 3 and laser 4 being another group. The entering port includes a first sub-port, a second sub-port, a third sub-port and a fourth sub-port. The first sub-port and the second sub-port are located on the upper side of the silicon optical chip and are respectively used for coupling the light beams from the laser 1 and the laser 2 into the silicon optical chip. The light beams from the laser 1 and the laser 2 are different in at least one of the sweep slope, the frequency and the wavelength. The third sub-port and the fourth sub-port are located on the lower side of the silicon optical chip and are respectively used for coupling the light beams from the laser 3 and the laser 4 into the silicon optical chip. The light beams from the laser 3 and the laser 4 are different in at least one of the sweep slope, the frequency and the wavelength.

[0202] The light beams of each group of lasers form two sub-beams after being split, and the beam combiner can combine one sub-beam of each laser in each group of lasers to form a combined beam. Another sub-beam of each laser is input into a feedback module. For the combined beam, it is split into two parts by a beam splitter, one part of the beam is input into the beam combiner as a feedback beam, and the other part is split (which can be regarded as a tree-shaped beam splitter) to obtain a to-be-transmitted light beam and a local light beam. The to-be-transmitted light beam is input into an optical loopback device (taking PBRS as an example), and the local light beam is input into a mixer.

[0203] In the case of two groups of lasers, the long arm loop of the feedback part can be common. Referring to FIG. 23, two combined beams generate one feedback beam each after passing through a beam splitter, and the two feedback beams can be input into a beam combiner for combination. The combined beam passes through multiple layers of beam splitting (also a tree-shaped beam splitter) to obtain four sub-beams, which are respectively input into four mixers, and the other input of the mixers is another sub-beam obtained from the four lasers in the first beam splitting. The four mixers can mix to obtain the feedback result. For related description, please refer to the introduction of FIG. 22.

[0204] In the silicon optical chip of FIG. 23, the optical paths for processing two groups of lasers can be arranged on both sides of the silicon optical chip, which improves the integration of the device, reduces the intersection points, realizes more emission beams, and ensures the emission power of each emission beam.

[0205] Optionally, the transceiver module 11 further includes a laser driving module for driving the laser to work.

[0206] As a possible implementation, the detection device further includes one or more optical elements, such as lenses and the like.

[0207] Exemplarily, as shown in FIG. 23, a lens can be arranged in the transceiver module 11. The emission and / or reception beam needs to pass through the lens in front of the transceiver coupler to shape the beam. The lens or lens group can deflect the laser of different transceiver channels to different pointing angles.

[0208] Further, the detection device can further include other optical elements, such as QWP, HWP and the like. The QWP in the lens or lens group is used for conversion between the emitted laser and the received backscattered light of different polarizations. For example, the emitted TE direction polarized light becomes elliptical or circular polarized light after passing through the QWP, and the backscattered light after reflection of the target again passes through the QWP and becomes TM direction polarized light.

[0209] The embodiment of the present application further provides a laser radar, which includes the aforementioned detection device.

[0210] Further, referring to FIG. 24, the laser radar further includes a signal processing device for controlling the detection device and / or processing the data output by the detection device, such as the mixing result or the time of flight (TOF) result.

[0211] As a possible implementation, the signal processing device can include one or more of a sampling analog-to-digital converter, a digital-to-analog converter (DAC), a multiplexer, a logic chip, a system on chip (SOC) chip, etc. Exemplarily, the logic chip can include a field programmable gate array (PFPGA), and of course, the present application is also applicable to a signal processing device using other logic chips. In an exemplary signal processing device, as shown in FIG. 24, a multiplexer is designed before an analog-to-digital converter, which is used to collect signals output by the signal path and feedback path detectors. The multiplexer can switch signals between different channels to achieve time division sampling between multiple signals, thereby reducing the number of analog-to-digital converters and the signal processing pressure. A digital-to-analog converter is used to generate a laser sweep modulation waveform, and each DAC drives a laser through a laser driving circuit. The laser driving circuit can also include an optical phase-locked loop (OPLL) feedback loop. The signal processing module controls the sampling timing of each channel through the logic chip and transmits the collected signals to the SOC chip for data processing.

[0212] In FIG. 24, the rotating mirror (i.e., a multi-faceted rotating mirror) can be included in the scanning module.

[0213] Optionally, the lidar can also include one or more optical elements, such as a lens (Lens), a QWP, etc. as shown in FIG. 24.

[0214] Further, the housing is used to provide a receiving space to accommodate other modules in the lidar, such as the detection device and the signal processing device.

[0215] The embodiments of the present application also provide a terminal, which includes the aforementioned detection device or the aforementioned lidar.

[0216] Please refer to FIG. 25, which is a structural schematic diagram of a vehicle including a lidar provided by the present application. The lidar can perceive the surrounding environment of the vehicle and obtain related information of targets in the surrounding environment. The related information of the targets can be used to control the vehicle or assist the driver in driving.

[0217] It should be understood that the installation position of the lidar shown in FIG. 25 is only an example. In specific implementations, the detection device can be installed at other positions, such as being installed at the top of the cabin, or can also be installed at the head of the vehicle, the side of the vehicle, or the tail of the vehicle, etc.

[0218] The words "exemplary" or "for example" are used herein to mean "serving as an example, instance, or illustration." Any embodiment or design described herein as "exemplary" or "for example" is not necessarily to be construed as preferred or advantageous over other embodiments or designs. Rather, the exemplary or for example embodiments are to be

[0219] The term "at least one", as used herein, means one or more, the term "multiple" means two or more. The phrase "at least one of", or the like, as used herein, refers to any combination of one or more of the items in the list of items, including individual items in the list. For example, "at least one of a, b, or c" can refer to: a; b; c; (a and b); (a and c); (b and c); or (a and b and c), where a, b and c can be individual items or a plurality of items. The term "and / or", as used herein, describes the association between associated objects, and means that there can be three kinds of relationships, for example, A and / or B can mean that A exists alone, A and B exist together, and B exists alone, where A and B can be singular or plural. The character " / " generally means that the associated objects before and after it are in an "or" relationship.

[0220] In addition, unless otherwise stated, the ordinal numbers "first", "second", etc. used in the embodiments of the present application are used to distinguish the multiple objects, and are not used to limit the order, time sequence, priority or importance of the multiple objects.

Claims

1. A detection device, characterized in that, The detection device comprises a transceiver module and a rotating mirror, wherein: The rotating mirror comprises M reflecting surfaces, M is an integer and M≥2, the included angle between the M reflecting surfaces and a first plane is distributed in an angular difference of a first angle α, and the first plane is perpendicular to the activity axis of the rotating mirror; The transceiver module comprises at least N transceiver ports, N is an integer and N≥4; The transceiver module is used to generate N transmission line beams, the pointing angles of the N transmission line beams are different; The N transmission line beams are reflected to the object space through the rotating mirror; The N transmission line beams comprise adjacent first and second line beams, the included angle of the pointing angles of the first and second line beams is a second angle x, The first angle α and the second angle x satisfy the following relationship: x=M×α.

2. The probe device of claim 1, wherein, The M reflecting surfaces are used to rotate around the activity axis to scan the N transmission line beams to the object space in different time periods, The scanning tracks of the N transmission line beams after being reflected by the M reflecting surfaces are M×N scanning lines arranged at intervals.

3. The probe device according to claim 1 or 2, characterized in that The 2×M scanning lines formed by the first and second line beams after being reflected by the M reflecting surfaces are uniformly distributed at intervals of the first angle α.

4. The probe device according to any one of claims 1 to 3, characterized in that The second angle x is the maximum value of the included angles of the adjacent line beams in the N transmission line beams.

5. The probe device according to any one of claims 1-4, characterized in that, The N transmission line beams comprise K third line beams adjacent to each other, the included angle of the pointing angles between any two adjacent line beams among the K third line beams is a third angle y1; The third angle y1 satisfies the following relationship: y1*K=α, wherein K is an integer and K>1.

6. The probe device of claim 5, wherein, The K×M scanning lines formed by the K third line beams after being reflected by the M reflecting surfaces are uniformly distributed at intervals of the third angle y1.

7. The probe device according to claim 5 or 6, characterized in that The angle formed by the first and second line beams is closer to the edge of the N transmission line beams than the angle formed by the K third line beams.

8. The probe device according to any one of claims 5-7, characterized in that, The N transmission line beams further comprise a fourth line beam, the K third line beams and the fourth line beam are adjacent to each other in sequence, the included angle between the fourth line beam and a fifth line beam is a fourth angle z1, and the fifth line beam is the line beam closest to the fourth line beam among the K third line beams; The third angle y1 and the fourth angle z1 satisfy the following relationship: z1+(K-1)y1=M×α.

9. The probe device of claim 8, wherein, The K×M scanning lines formed by the K third line beams after being reflected by the M reflecting surfaces are a first scanning line group, The M scanning lines formed by the fourth line beam after being reflected by the M reflecting surfaces are a second scanning line group, The first scanning line group and the second scanning line group do not overlap, and the angle interval between the edge of the first scanning line group close to the second scanning line group and the edge of the second scanning line group close to the first scanning group is the third angle y1.

10. The probe device according to any one of claims 1-9, characterized in that, The N transmission line beams comprise J sixth line beams and a seventh line beam adjacent to each other in sequence, The included angle of the pointing angles between any two adjacent line beams among the J sixth line beams is a fifth angle y2; The fifth angle y2 satisfies the following relationship: y2*J=α, wherein J is an integer and J>1, An included angle between the seventh beam and the eighth beam is a sixth angle z2, and the eighth beam is a beam closest to the seventh beam among the J sixth beams; The sixth angle z2 and the fifth angle y2 satisfy the following relationship: z2=M*α.

11. The probe device of claim 10, wherein, The J sixth beams form J*M scanning lines after passing through the M reflecting surfaces, and the J*M scanning lines are a third scanning line group, The seventh beam forms M scanning lines after passing through the M reflecting surfaces, and the M scanning lines are a fourth scanning line group, The third scanning line group and the fourth scanning line group do not overlap, and an angle interval between the third scanning line group close to an edge of the fourth scanning line group and the fourth scanning line group close to an edge of the third scanning line group is a first angle α.

12. The probe device according to any one of claims 1-4, characterized in that The N emission beams include an adjacent ninth beam and a tenth beam, and an included angle of pointing angles of the ninth beam and the tenth beam is a seventh angle y3; The seventh angle y3 satisfies the following relationship: y3*2=M*α.

13. The probe device of claim 12, wherein, The ninth beam forms M scanning lines after passing through the M reflecting surfaces, and the tenth beam forms M scanning lines after passing through the M reflecting surfaces, Half of the fifth scanning line group close to the sixth scanning line group is interwoven with half of the sixth scanning line group close to the fifth scanning line group, Scanning lines of the interwoven part of the fifth scanning line group and the sixth scanning line group are uniformly distributed at an interval of α / 2.

14. The probe device according to claim 12 or 13, characterized in that An angle formed by the first beam and the second beam is closer to an edge of the N emission beams than an angle formed by the ninth beam and the tenth beam.

15. The probe device of claim 2, wherein, A distribution density of scanning lines in a region of interest ROI of a field of view of the detection device is higher than a distribution density of scanning lines in a non-ROI of the field of view.

16. The probe device according to any one of claims 1-15, characterized in that The detection device further includes a lens, The lens is arranged between the N transceiver ports and the rotating mirror, and an included angle of pointing angles of two emission beams in the N emission beams is related to a distance between the two emission beams corresponding transceiver ports and a focal length of the lens.

17. The probe device according to any one of claims 1-16, characterized in that Each emission beam in the N emission beams includes a light beam from at least two lasers; In the light beams of the at least two lasers, at least one of a sweep frequency slope, a frequency, and a wavelength of the light beams of any two lasers is different.

18. The detection device according to any one of claims 1-17, wherein The transceiver module is further configured to receive N receiving beams; The transceiver module further includes a plurality of mixers, each mixer in the plurality of mixers corresponding to at least one emission beam in the N emission beams and at least one receiving beam in the N receiving beams; Each mixer in the plurality of mixers is configured to mix a local oscillator light beam of the corresponding at least one emission beam and the corresponding at least one receiving beam to obtain a mixing result.

19. The probe device of claim 18, wherein, The mixer is a 90° mixer or a 180° mixer.

20. The probe device of claim 18 or 19, wherein, The transceiving module comprises N transceiving ports and N mixers, and the N transceiving ports and the N mixers are arranged alternately along the arrangement direction of the N transceiving ports.

21. The probe device according to claim 19 or 20, characterized in that The N transceiving ports are also configured to receive the N receiving line bundles, The transceiving module further comprises a plurality of optical loopback devices, each of the plurality of optical loopback devices comprises a first port, a second port and a third port, the second port is connected to at least one of the transceiving ports, and the third port is connected to one of the plurality of mixers; The optical loopback device is configured to receive a to-be-transmitted line bundle from the first port and output the to-be-transmitted line bundle from the second port to exit from the corresponding transceiving port; The optical loopback device is also configured to obtain a receiving line bundle provided by the corresponding transceiving port and output the receiving line bundle from the third port to the corresponding mixer.

22. The probe device of claim 21, wherein, The transceiving module comprises M transceiving ports, M is an integer and M>N, The plurality of optical loopback devices comprises a first optical loopback device, the second port of the first optical loopback device is connected to the root end of an optical switch tree, the leaf end of the optical switch tree is connected to a plurality of transceiving ports, and the optical switch tree comprises a plurality of optical switches arranged in a tree structure; The optical switch tree is configured to select one of the transceiving ports, so that the to-be-transmitted line bundle from the second port of the first optical loopback device exits from the selected transceiving port.

23. The probe device of claim 21, wherein, The transceiving module comprises M transceiving ports, M is an integer and M>N, The N optical loopback devices comprise a second optical loopback device, the second port of the second optical loopback device is connected to the root end of a beam splitter tree, the leaf end of the beam splitter tree is connected to a plurality of transceiving ports, and the beam splitter tree comprises a plurality of beam splitters arranged in a tree structure; The beam splitter tree is configured to split the optical beam received from the root end into multiple paths and exit from the plurality of transceiving ports connected to the leaf end respectively.

24. The method according to any one of claims 18-23, characterized by, The transceiving module comprises a silicon optical chip, the silicon optical chip comprises an entering port, the at least N transceiving ports, the plurality of mixers and an optical waveguide, and the optical waveguide is configured to transmit optical beams between components of the silicon optical chip; The entering port is configured to couple the optical beam from the laser into the silicon optical chip.

25. The probe device of claim 24, wherein, The silicon optical chip further comprises a first beam splitter, a second beam splitter, a first beam combiner, a first beam splitter tree and a feedback module, The first beam splitter is configured to split the first optical beam from the first laser into a first optical beam and a second optical beam, The second beam splitter is configured to split the second optical beam from the second laser into a third optical beam and a fourth optical beam, The first beam combiner is configured to combine the first optical beam and the third optical beam into a first combined optical beam, The first beam splitter tree is configured to split the first combined optical beam into a first feedback optical beam, a plurality of first to-be-transmitted optical beams and a plurality of first local oscillator optical beams, the plurality of first to-be-transmitted optical beams are input into a plurality of optical loopback devices respectively, and the plurality of first local oscillator optical beams are input into a plurality of mixers respectively; The feedback module is configured to mix the first feedback optical beam with the second optical beam and the fourth optical beam respectively to obtain a feedback result.

26. The probe device of claim 25, wherein, The plurality of first to-be-transmitted optical beams and the plurality of first local oscillator optical beams are arranged alternately.

27. The probe device according to any of claims 24-26, characterized by No optical amplifier is arranged in the silicon optical chip.

28. The probe device of any one of claims 1-27, wherein, Each of the N transmit beams comprises a frequency modulated continuous wave, FMCW.

29. A lidar, comprising: The laser radar comprises a signal processing device and a probe device according to any one of claims 1-28, The signal processing device is configured to control the probe device and / or process data output by the probe device.

30. A terminal, characterized by The terminal comprises a probe device according to any one of claims 1-28, Or, a laser radar according to claim 29.

31. The terminal according to claim 30, characterized by The terminal is a vehicle, a drone or a robot.

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