FMCW lidar and mobile device

Abstract

The invention provides an FMCW laser radar and a mobile device. The FMCW laser radar comprises a first light source module, a second light source module, a first mode converter and a mode multiplexer. The first light source module is used for generating first detection light and first local oscillation light, and the first detection light and the first local oscillation light are both fundamental mode light signals; the second light source module is used for generating second detection light and second local oscillation light, the second detection light and the second local oscillation light are both fundamental mode optical signals, and the first detection light and the second detection light are different in wavelength; the first mode converter is used for receiving the first detection light and converting the first detection light into a non-fundamental mode light signal; and the mode multiplexer is used for receiving the second detection light and the first detection light output by the first mode converter, and performing mode multiplexing to form a beam of detection light for emitting so as to detect a target object. The objective of the invention is to improve the current situation of poor detection effect of a laser radar employing dual lasers to cooperate with frequency sweep detection in the prior art.

Description

Technical Field

[0001] The present application relates to the field of radar technology, and more specifically, to a FMCW laser radar and a movable device. Background Art

[0002] Frequency Modulated Continuous Wave (FMCW) lidar can measure distance and speed at the same time. It is widely used in smart transportation, unmanned driving and other fields, and can provide safer and more reliable distance and speed information for autonomous driving or assisted driving.

[0003] For frequency modulated continuous wave (FMCW) laser radar, if you want to obtain the two information of distance and speed, you need to use two different sweep waveforms to achieve the solution. In the related art, some FMCW laser radars use dual lasers to achieve the measurement of the distance and speed of the target object. Specifically, two lasers simultaneously emit sweep signals with different sweep waveforms, and the distance and speed measurement can be achieved by combining the beat frequencies corresponding to the two lasers at the same time; the dual laser detection method is higher in detection efficiency than the single laser detection method. In the related art, the FMCW laser radar using dual lasers usually needs to use a wavelength division multiplexer (wavelength multiplexer) to combine the detection light obtained based on the two lasers, so that the two detection lights are detected in the form of the same beam of light. In addition, a wavelength division multiplexer (wavelength demultiplexer) is required to demultiplex the echo light formed by the above two detection lights, so that the echo light corresponding to each laser beats with the corresponding local oscillator light. However, the performance of the wavelength division multiplexer is very sensitive to environmental changes. For example, the bandwidth of the wavelength division multiplexer's multiplexed signal fluctuates significantly due to the influence of temperature. Since the temperature range of the lidar's application environment is large, and the heat generated by the lidar itself will further enhance the temperature fluctuations inside the lidar, all of these will cause the temperature of the wavelength division multiplexer to change, which in turn will cause large fluctuations in the loss of the wavelength division multiplexer when multiplexing the detection light, resulting in poor actual detection effect of the FMCW lidar. Summary of the invention

[0004] To solve the above problems, the present application provides an FMCW laser radar and a movable device, aiming to improve the current situation in which the laser radar using dual lasers with swept frequency detection in the related technology has poor detection effect.

[0005] In a first aspect, the present application provides an FMCW laser radar, comprising: a first light source module, a second light source module, a first mode converter and a mode multiplexer; the first light source module is used to generate a first detection light and a first local oscillation light, both of which are fundamental mode light signals; the second light source module is used to generate a second detection light and a second local oscillation light, both of which are fundamental mode light signals, and the first detection light and the second detection light have different wavelengths; the first mode converter is used to receive the first detection light and mode-convert it into a non-fundamental mode light signal; the mode multiplexer is used to receive the second detection light and the first detection light outputted via the first mode converter, and mode-multiplex them into a beam of detection light for emission to detect a target object.

[0006] In the above technical solution, the mode multiplexer can mode-multiplex the second detection light and the first detection light outputted via the first mode converter, and the performance of the mode multiplexer is not limited by changes in the environment, and the mode multiplexing process is not limited by changes in wavelength, thus ensuring the reliability of the mode multiplexer when mode-multiplexing two lights, and further ensuring the actual detection effect of the FMCW laser radar. At the same time, by setting the first mode converter to mode-convert the first detection light, the first detection light and the second detection light are lights of two different modes, and by distinguishing and dividing them, it is ensured that when a beam of light is subsequently split, the light corresponding to the first light source module and the second light source module can be split, respectively, to ensure the detection reliability of the first light source module and the second light source module.

[0007] In combination with the first aspect, in some possible implementations, the FMCW laser radar also includes: a mode demultiplexer, a second mode converter and a photoelectric detection module; the mode demultiplexer is used to receive the echo light and mode-demultiplex it into a first echo light and a second echo light, the first echo light is formed by the first detection light being reflected by the target object, and the second echo light is formed by the second detection light being reflected by the target object; the second mode converter is provided between the mode demultiplexer and the photoelectric detection module, and is used to receive the first echo light and mode-convert it into a fundamental mode light signal; the photoelectric detection module is used to receive the first local oscillation light, the second local oscillation light, the second echo light and the first echo light output by the second mode converter.

[0008] In the above technical solution, the FMCW laser radar provided in the embodiment of the present application can also perform mode demultiplexing on a beam of combined light formed after reflection to form a first echo light and a second echo light corresponding to the first light source module and the second light source module, and the performance of the mode demultiplexer is not limited by changes in the environment, and the mode demultiplexing process is not limited by changes in wavelength. In this way, the reliability of the mode demultiplexing of a beam of light by the mode demultiplexer is guaranteed, and the actual detection effect of the FMCW laser radar is guaranteed. At the same time, by setting a second mode converter to perform mode conversion on the first echo light, the mode of the first echo light is made the same as that of the first local oscillation light, which ensures the uniformity of the received signal of the photoelectric detection module, that is, the beat frequency reliability of the photoelectric detection module is guaranteed, and the actual detection effect of the FMCW laser radar is further guaranteed.

[0009] In combination with the first aspect and the above-mentioned implementation methods, in some possible implementation methods, the photoelectric detection module includes: a first photoelectric detection module and a second photoelectric detection module; the first photoelectric detection module is used to receive the first local oscillation light and the first echo light output via the second mode converter; the second photoelectric detection module is used to receive the second local oscillation light and the second echo light.

[0010] In the above technical scheme, the first local oscillation light, the first echo light and the second local oscillation light, the second echo light are respectively processed by an independent first photoelectric detection module and a second photoelectric detection module, so as to obtain electrical signals related to the beat frequency signals corresponding to the first light source module and the second light source module, so that the subsequent signal processing module can obtain the device of the frequency of the above two beat frequency signals according to the above electrical signals, thereby ensuring the beat frequency reliability.

[0011] In combination with the first aspect and the above-mentioned implementation methods, in some possible implementation methods, the first light source module includes: a first laser and a first splitter module; the first laser is used to generate a first source light signal of a fundamental mode; the first splitter module is used to receive the first source light signal and split it into at least a first detection light and a first local oscillator light.

[0012] In the above technical solution, the first source light signal emitted by the first laser can be split into the corresponding first detection light and the first local oscillator light through the first splitter module. The structure is simple, and the splitting ratio can be set for the first splitter module so that the first splitter module can accurately split the first source light signal to ensure high reliability of the splitting.

[0013] In combination with the first aspect and the above-mentioned implementation methods, in some possible implementation methods, the second light source module includes: a second laser and a second splitter module; the second laser is used to generate a second source light signal of a fundamental mode; the second splitter module is used to receive the second source light signal and split it into at least a second detection light and a second local oscillator light.

[0014] In the above technical solution, the second source light signal emitted by the second laser can be split into the corresponding second detection light and the second local oscillator light through the second splitting module. The structure is simple, and the splitting ratio can be set for the second splitting module so that the second splitting module can accurately split the second source light signal to ensure high reliability of the splitting.

[0015] In combination with the first aspect and the above-mentioned implementation manner, in some possible implementation manners, the FMCW laser radar also includes a first nonlinear calibration module and a second nonlinear calibration module; the first splitter module is used to receive the first source light signal and split it into at least a first detection light, a first local oscillator light and a first calibration light, the first nonlinear calibration module includes a first splitter, a first optical delay line and a first photoelectric detection component, the first splitter is connected to the first splitter module to receive the first calibration light and split it into a first calibration signal and a second calibration signal, the first photoelectric detection component is used to receive the first calibration signal and the second calibration signal, and at least one output end of the first splitter is connected to the first optical delay line via the first optical The electrical detection component is connected so that the optical path of the first calibration signal is different from that of the second calibration signal; the second spectrometer module is used to receive the second source light signal and split it into at least a second detection light, a second local oscillator light and a second calibration light; the second nonlinear calibration module includes a second spectrometer, a second optical delay line and a second photoelectric detection component; the second spectrometer is connected to the second spectrometer module to receive the second calibration light and split it into a third calibration signal and a fourth calibration signal; the second photoelectric detection component is used to receive the third calibration signal and the fourth calibration signal; at least one output end of the second spectrometer is connected to the second photoelectric detection component via the second optical delay line so that the optical path of the third calibration signal and the fourth calibration signal are different.

[0016] In the above technical solution, the source light signals emitted by the first spectroscopic module and the second spectroscopic module can be calibrated in real time through the first nonlinear calibration module and the second nonlinear calibration module, respectively, so that the operator can find problems in time and adjust them, thereby ensuring the accuracy of the FMCW laser radar detection results.

[0017] In combination with the first aspect and the above implementations, in some possible implementations, the mode multiplexer, the first mode converter, the first light splitting module, the second light splitting module and the photoelectric detection module are integrated into the same optical chip.

[0018] In the above technical solution, they are integrated on the same optical chip, which reduces the individual occupied area of ​​these devices, thereby allowing the FMCW laser radar to develop towards miniaturization.

[0019] In combination with the first aspect and the above-mentioned implementation methods, in some possible implementation methods, the FMCW laser radar also includes an optical amplification module; the optical amplification module is used to receive the detection light and amplify the detection light.

[0020] In the above technical solution, the optical amplifier module can amplify the detection light to improve the detection capability of the detection light and ensure the detection effect of the FMCW laser radar.

[0021] In combination with the first aspect and the above-mentioned implementation methods, in some possible implementation methods, the FMCW laser radar also includes a scanning module; the scanning module is used to reflect the detection light so that the detection light is emitted outside the laser radar, and the scanning module can rotate relative to the shell of the laser radar so that the detection light forms a detection field of view outside the laser radar.

[0022] In a second aspect, the present application provides an FMCW laser radar, comprising: a first light source module, a second light source module, a first mode converter and a mode multiplexer; the first light source module is used to generate a first light signal, the first light signal is a fundamental mode light signal; the second light source module is used to generate a second light signal, the second light signal is a fundamental mode light signal, and the wavelengths of the first light signal and the second light signal are different; the first mode converter is used to receive the first light signal and mode-convert it into a non-fundamental mode light signal; the mode multiplexer is used to receive the second light signal and the first light signal output via the first mode converter, and mode-multiplex it into a beam of multiplexed light signal; a beam splitting module is used to receive the multiplexed light signal and split it to obtain detection light and local oscillation light, the detection light is used to detect a target object, the detection light comprises a first detection light and a second detection light, the first detection light is part of the first light signal, and the second detection light is part of the second light signal, the local oscillation light comprises a first local oscillation light and a second local oscillation light, the first local oscillation light is part of the first light signal, and the second local oscillation light is part of the second light signal.

[0023] In the above technical solution, the mode multiplexer can mode-multiplex the second optical signal and the first optical signal outputted via the first mode converter, and the performance of the mode multiplexer is not limited by changes in the environment, and is not limited by changes in wavelength during the mode multiplexing process. In this way, the reliability of the mode multiplexer mode multiplexing two lights is guaranteed, thereby ensuring the actual detection effect of the FMCW laser radar. At the same time, a beam splitting module can be used to split the multiplexed optical signals corresponding to the optical signals of the two light source modules, thereby reducing the occupied area of ​​the beam splitting module in the FMCW laser radar, so that the FMCW laser radar can be developed towards miniaturization. Moreover, the first light source module and the second light source module correspond to the same beam splitting module, that is, the splitting ratio is the same. In this way, through a beam splitting module, the corresponding optical signals of the first light source module and the second light source module can achieve the same proportion of beam splitting processing, thereby ensuring the accuracy and reliability of the beam splitting.

[0024] In combination with the second aspect and the above-mentioned implementation methods, in some possible implementation methods, the FMCW laser radar also includes: a first mode demultiplexer, a second mode converter, a second mode demultiplexer, a third mode converter and a photoelectric detection module; the first mode demultiplexer is used to receive the echo light and mode-demultiplex it into the first echo light and the second echo light, the first echo light is formed by the first detection light reflected by the target object, and the second echo light is formed by the second detection light reflected by the target object; the second mode converter is arranged between the first mode demultiplexer and the photoelectric detection module, and is used to receive the first echo light and mode-convert it into a fundamental mode light signal; the second mode demultiplexer is used to receive the local oscillation light and mode-demultiplex it into the first local oscillation light and the second local oscillation light; the third mode converter is arranged between the second mode demultiplexer and the photoelectric detection module, and is used to receive the first local oscillation light and mode-convert it into a fundamental mode light signal; the photoelectric detection module is used to receive the first local oscillation light, the second local oscillation light, the second echo light and the first echo light output via the second mode converter.

[0025] In the above technical solution, the local oscillator light and the echo light can be demultiplexed by the first mode demultiplexer and the second mode demultiplexer, and the performance of the first mode demultiplexer and the second mode demultiplexer is not limited by changes in the environment, and the mode demultiplexing process is not limited by changes in wavelength. In this way, the reliability of the mode demultiplexing of the local oscillator light and the echo light by the first mode demultiplexer and the second mode demultiplexer is guaranteed, thereby ensuring the actual detection effect of the FMCW laser radar. At the same time, by setting the second mode converter and the third mode converter, the first echo light and the first local oscillator light can be mode-converted, so that the mode of the first echo light is the same as that of the second echo light, and the mode of the first local oscillator light is the same as that of the second local oscillator light, thereby ensuring the uniformity of the received signal of the photoelectric detection module, that is, ensuring the beat frequency reliability of the photoelectric detection module, thereby further ensuring the actual detection effect of the FMCW laser radar.

[0026] In combination with the second aspect and the above-mentioned implementation methods, in some possible implementation methods, the photoelectric detection module includes: a first photoelectric detection module and a second photoelectric detection module; the first photoelectric detection module is used to receive the first echo light output via the second mode converter and the first local oscillation light output via the third mode converter; the second photoelectric detection module is used to receive the second echo light output via the first mode demultiplexer and the second local oscillation light output via the second mode demultiplexer.

[0027] In the above technical scheme, the first local oscillation light, the first echo light and the second local oscillation light, the second echo light are respectively processed by an independent first photoelectric detection module and a second photoelectric detection module, so as to obtain electrical signals related to the beat frequency signals corresponding to the first light source module and the second light source module, so that the subsequent signal processing module can obtain the device of the frequency of the above two beat frequency signals according to the above electrical signals, thereby ensuring the beat frequency reliability.

[0028] In combination with the second aspect and the above-mentioned implementations, in some possible implementations, the mode multiplexer, the first mode converter, the beam splitting module and the photoelectric detection module are integrated into the same optical chip.

[0029] In the above technical solution, they are integrated on the same optical chip, which reduces the individual occupied area of ​​these devices, thereby allowing the FMCW laser radar to develop towards miniaturization.

[0030] In a third aspect, the present application provides a movable device, comprising the FMCW laser radar in the above-mentioned first and second aspects or any possible implementation of the first and second aspects and a movable device body, wherein the FMCW laser radar is mounted on the device body. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a structural schematic diagram of a FMCW laser radar provided in an embodiment of the present application;

[0032] Figure 2 is a schematic diagram of the structure of another FMCW laser radar provided in an embodiment of the present application;

[0033] Figure 3 is a structural schematic diagram of a first light source module provided in an embodiment of the present application;

[0034] Figure 4 is a structural schematic diagram of a second light source module provided in an embodiment of the present application;

[0035] Figure 5 is a structural schematic diagram of a light source device provided in an embodiment of the present application;

[0036] Figure 6 is a schematic diagram of the structure of another FMCW laser radar provided in an embodiment of the present application;

[0037] Figure 7 It is a structural schematic diagram of another FMCW laser radar provided in an embodiment of the present application;

[0038] Figure 8 It is a structural schematic diagram of another FMCW laser radar provided in an embodiment of the present application;

[0039] Fig. 9It is a structural schematic diagram of another FMCW laser radar provided in an embodiment of the present application;

[0040] Fig.10 It is a structural schematic diagram of another FMCW laser radar provided in an embodiment of the present application;

[0041] Fig.11 It is a structural schematic diagram of another FMCW laser radar provided in an embodiment of the present application;

[0042] Fig.12 It is a structural schematic diagram of another FMCW laser radar provided in an embodiment of the present application;

[0043] Fig.13 It is a structural schematic diagram of another FMCW laser radar provided in an embodiment of the present application;

[0044] Fig.14 It is a structural schematic diagram of another FMCW laser radar provided in an embodiment of the present application.

[0045] Among them, the reference numerals in the figure are:

[0046] 100, light source device; 101, first light source module; 1011, first laser; 1012, first spectrometer module; 102, second light source module; 1021, second laser; 1022, second spectrometer module; 103, first nonlinear calibration module; 104, second nonlinear calibration module; 200, photoelectric detection module; 201, first photoelectric detection module; 202, second photoelectric detection module; 300, signal processing module; 400, first mode converter; 500, mode multiplexer; 600, mode demultiplexer; 700, second mode converter; 800, beam splitter module; 900, first mode demultiplexer; 1000, second mode demultiplexer; 1100, third mode converter; 1200, optical amplification module; 1300, scanning module; 1400, transceiver module. DETAILED DESCRIPTION

[0047] The technical solution in the present application will be described clearly and in detail below in conjunction with the accompanying drawings. In the description of the embodiments of the present application, unless otherwise specified, " / " means or, for example, A / B can mean A or B: "and / or" in the text is only a description of the association relationship of associated objects, indicating that there can be three relationships, for example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, in the description of the embodiments of the present application, "multiple" means two or more than two.

[0048] In the following, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as suggesting or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features.

[0049] Before introducing the embodiments of the present application, the professional terms that may be involved in the embodiments of the present application are explained below.

[0050] Lidar: A radar system that uses laser beams to detect the position, speed and other characteristic quantities of a target. Its working principle is to emit a detection signal (laser beam) to the target object, and then compare the received signal reflected from the target object (echo signal) with the local oscillator signal. After appropriate processing, relevant information about the target object relative to the Lidar can be obtained, such as distance, direction, height, speed, attitude, and even shape parameters.

[0051] FMCW LiDAR: The working process of FMCW LiDAR can be simply summarized as follows: the continuous wave obtained by frequency modulation is used as the local oscillator signal and the detection signal. The LiDAR transmits the detection signal. The echo signal formed by the target object reflecting the detection signal is mixed with the local oscillator signal through the receiver to obtain the beat frequency of the mixed signal, thereby calculating the required information.

[0052] Local oscillator signal: The local oscillator signal is used as a reference signal for the detection signal. It has the same time-frequency characteristics as the detection signal, that is, the swept frequency waveform is consistent. The local oscillator signal is used to coherently beat the echo signal formed by the detection signal to obtain a beat signal. The local oscillator signal and the detection signal can be obtained by splitting a beam of light or generated by different laser sources.

[0053] Beat frequency signal: in the embodiment of the present application, it refers to the difference frequency signal between the local oscillator signal and the echo signal after coherence.

[0054] In application, the FMCW laser radar provided in the embodiment of the present application is not only suitable for fast, efficient and accurate distance measurement and speed measurement of close-range target objects, but also for fast, efficient and accurate distance measurement and speed measurement of long-range target objects. It can be applied to smart transportation, aerospace, resource exploration, urban planning, agricultural development, water conservancy projects, land use, environmental monitoring, metallurgical manufacturing, textile manufacturing and any other fields that require distance measurement and speed measurement. Specifically, it can be applied to unmanned vehicles, drones, robots, positioning systems, navigation systems, loading and unloading and handling equipment, metallurgical process control equipment, non-contact measurement equipment, etc.

[0055] In order to improve the detection efficiency of laser radar, at present, FMCW laser radar usually uses dual lasers to measure the distance and speed of the target object, that is, FMCW laser radar can simultaneously emit sweeping signals with different sweeping waveforms, and the beat frequency corresponding to the two lasers at the same time can be combined to achieve distance and speed measurement. In the related technology, FMCW laser radar using dual lasers usually needs to use a wavelength multiplexer and a wavelength demultiplexer, wherein the wavelength multiplexer is used to combine the detection light obtained by the two lasers so that the two detection lights are detected in the form of the same beam of light; the wavelength demultiplexer demultiplexes the echo light formed by the above two detection lights so that the echo light corresponding to each laser beats with the corresponding local oscillator light. However, the performance of the wavelength multiplexer and wavelength demultiplexer is limited by environmental changes. For example, the bandwidth of the multiplexed signal fluctuates significantly due to the influence of the ambient temperature. In addition, since the temperature range of the application environment of the FMCW laser radar is large, and the heat generated by the FMCW laser radar itself will further enhance the temperature fluctuations inside the FMCW laser radar, these will cause the temperature of the wavelength multiplexer and wavelength demultiplexer to change, which in turn causes the loss of the wavelength multiplexer and wavelength demultiplexer when multiplexing the detection light to fluctuate greatly, resulting in poor actual detection effect of the FMCW laser radar.

[0056] To this end, the present application provides an FMCW laser radar and a movable device. The FMCW laser radar can multiplex optical signals of different wavelengths based on different modes, and is insensitive to the wavelength of the optical signal and the ambient temperature, thereby ensuring the detection reliability and accuracy of the FMCW laser radar, and can improve the current situation in which the FMCW laser radar using dual lasers with swept frequency detection in related technologies has poor detection effect.

[0057] The FMCW laser radar and movable device provided in the present application are exemplarily introduced below with reference to the accompanying drawings.

[0058] For example, Figure 1 As shown, the FMCW laser radar may include a light source device 100, a photoelectric detection module 200 and a signal processing module 300. The light source device 100 is used to transmit a detection light signal to the target object. The photoelectric detection module 200 is used to receive an echo signal reflected from the target object so as to beat the echo signal with the local oscillator signal to obtain a beat signal. The signal processing module 300 completes the calculation of the distance and speed of the target object relative to the FMCW laser radar based on the beat signal of the photoelectric detection module 200 to complete the detection of the FMCW laser radar.

[0059] It is worth explaining here that the photoelectric detection module 200 provided in the embodiment of the present application can be any device that can receive the local oscillator signal corresponding to the light source device 100, and the echo signal formed by the detection signal corresponding to the light source device 100 reflected by the target object, and output an electrical signal related to the beat frequency signal corresponding to the local oscillator signal of the light source device 100, so that the signal processing module 300 can obtain the frequencies of the above two beat frequency signals according to the above electrical signal.

[0060] Optionally, the photoelectric detection module 200 may include a photoelectric detector. At this time, in the process of receiving the local oscillator signal and the echo signal, the local oscillator signal and the echo signal beat each other in the manner of a free space light signal beat, and the photoelectric detector performs photoelectric conversion on the beat signal, thereby obtaining an electrical signal related to the beat signal.

[0061] Optionally, the photoelectric detection module 200 may also include an optical mixer and a balanced photodetector (Balanced Photo Detector, BPD). At this time, the optical mixer is used to receive the above-mentioned local oscillator signal and the echo signal so that the local oscillator signal and the echo signal are beat-frequencyed therein. The balanced photodetector is used to balance the beat-frequency signal to detect the beat-frequency signal, thereby obtaining an electrical signal related to the beat-frequency signal. The specific structure of the photoelectric detection module 200 provided in the embodiment of the present application can also be other structures, and the present application does not make specific restrictions on this.

[0062] Optionally, the signal processing module 300 may include a processor, and may also include at least one stage of amplification circuit, an analog to digital converter (ADC), a time to digital converter (TDC), a memory, etc. The processor may also have its own internal storage space and analog to digital conversion function to replace the analog to digital converter and the memory. In addition, the signal processing module 300 may also be connected to the active devices in the above modules to control the active devices to work in an orderly manner, which will not be described in detail.

[0063] In order to improve the detection efficiency of the FMCW laser radar, the FMCW laser radar usually uses dual lasers to achieve the measurement of the distance and speed of the target object, that is, the light source device 100 in the FMCW laser radar can generate a first signal and a second signal with different wavelengths. For example, Figure 2As shown, the light source device 100 may include a first light source module 101 and a second light source module 102, the first light source module 101 is used to generate a first detection light and a first local oscillation light, the wavelength of the first detection light and the first local oscillation light is λ1, the second light source module 102 is used to generate a second detection light and a second local oscillation light, the wavelength of the second detection light and the second local oscillation light is λ2, the first detection light and the second detection light are used to detect the target object, the first local oscillation light and the second local oscillation light enter the photoelectric detection module 200, so that the photoelectric detection module 200 can generate a beat frequency signal based on the first local oscillation light and the second local oscillation light and the echo signal corresponding to the first detection light and the second detection light. Moreover, the first detection light, the first local oscillation light, the second detection light and the second local oscillation light are all fundamental mode light signals.

[0064] Alternatively, if Figure 3 As shown, the first light source module 101 may include a first laser 1011 and a first light splitting module 1012. The first laser 1011 is used to generate a first source light signal of a fundamental mode. The first light splitting module receives the first source light signal and splits the first source light signal into at least a first detection light and a first local oscillator light. In this way, the first source light signal emitted by the first laser 1011 can be split into corresponding first detection light and first local oscillator light through the first light splitting module 1012. The structure is simple, and the splitting ratio can be set for the first light splitting module 1012, so that the first light splitting module 1012 can accurately split the first source light signal to ensure high reliability of the splitting.

[0065] Here, it is worth noting that the first light splitting module 1012 can be any device that can split light according to a preset ratio, so as to split the first source light signal generated by the first laser 1011 into corresponding first detection light and first local oscillator light according to a preset splitting ratio. For example, the first light splitting module 1012 may include a beam splitter, a planar light waveguide (PLC) beam splitter, or a fused biconical taper (FBT, also known as fused taper) beam splitter, or a combination of the above devices, and the present application does not impose any specific limitation on this.

[0066] Alternatively, if Figure 4As shown, the second light source module 102 may include a second laser 1021 and a second light splitting module 1022. The second laser 1021 is used to generate a second source light signal of a fundamental mode. The second light splitting module receives the second source light signal and splits the second source light signal into at least a second detection light and a second local oscillator light. In this way, the second source light signal emitted by the second laser 1021 can be split into corresponding second detection light and second local oscillator light through the second light splitting module 1022. The structure is simple, and the splitting ratio can be set for the second light splitting module 1022, so that the second light splitting module 1022 can accurately split the second source light signal, ensuring high reliability of the splitting.

[0067] In one example, if Figure 5 As shown, the light source device 1 in the FMCW laser radar provided in the embodiment of the present application may also include a first nonlinear calibration module 103 and a second nonlinear calibration module 104 .

[0068] The first optical splitter module 1012 is used to receive the first source light signal and split it into at least the first detection light, the first local oscillator light and the first calibration light. The first nonlinear calibration module 103 is connected to the first optical splitter module 101 to receive the first calibration light. Optionally, the first nonlinear calibration module 103 may include a first optical splitter, a first optical delay line and a first photoelectric detection component. The first optical splitter is connected to the first optical splitter module 101 to receive the first calibration light and split it into the first calibration signal and the second calibration signal. The first photoelectric detection component is used to receive the first calibration signal and the second calibration signal. At least one output end of the first optical splitter is connected to the first photoelectric detection component via the first optical delay line so that the optical path of the first calibration signal and the second calibration signal are different.

[0069] The second optical splitter module 1022 is used to receive the second source light signal and split it into at least a second detection light, a second local oscillator light and a second calibration light. The second nonlinear calibration module 104 is connected to the second optical splitter module 102 to receive the second calibration light. Optionally, the second nonlinear calibration module 104 may include a second optical splitter, a second optical delay line and a second photodetection component. The second optical splitter is connected to the second optical splitter module 102 to receive the second calibration light and split it into a third calibration signal and a fourth calibration signal. The second photodetection component is used to receive the third calibration signal and the fourth calibration signal. At least one output end of the second optical splitter is connected to the second photodetection component via a second optical delay line so that the optical path lengths of the third calibration signal and the fourth calibration signal are different.

[0070] In this way, the source light signals emitted by the first laser 1011 and the second laser 1021 can be calibrated in real time through the first nonlinear calibration module 103 and the second nonlinear calibration module 104, respectively, so that the operator can find problems in time and adjust them, thereby ensuring the accuracy of the FMCW laser radar detection results.

[0071] In order to combine the detection lights obtained by the first light source module 101 and the second light source module 102 so that the two detection lights are detected in the form of the same light beam, in one example, Figure 6 As shown, the FMCW laser radar can also include a first mode converter 400 and a mode multiplexer 500. Along the transmission direction of the first detection light, the first mode converter 400 can be located downstream of the first light source module 101, which is used to receive the first detection light and convert the first detection light mode with a fundamental mode into a non-fundamental mode optical signal. The mode multiplexer 500 is used to receive the second detection light and the first detection light output via the first mode converter 400, and multiplex the two optical signal modes into a beam of detection light to achieve detection of the target object. The mode multiplexer 500 can mode-multiplex the second detection light and the first detection light output via the first mode converter 400, and the performance of the mode multiplexer 500 is not limited by environmental changes, and is not sensitive to wavelength during the mode multiplexing process. In this way, the reliability of the mode multiplexer 500 mode multiplexing two optical signals is guaranteed, thereby ensuring the actual detection effect of the FMCW laser radar.

[0072] In order to improve the integration of the FMCW laser radar, and then improve the reliability of the FMCW laser radar, and at the same time facilitate the miniaturization of the FMCW laser radar, optionally, the mode multiplexer 500, the first mode converter 400, the first splitter module 1012, the second splitter module 1022 and the photoelectric detection module 200 can be integrated into the same optical chip, reducing the area occupied by these devices alone, thereby ensuring the miniaturization of the FMCW laser radar. Here, it is worth noting that other devices can also be integrated on the chip, and this application does not make specific restrictions on this.

[0073] After the first detection light and the second detection light are emitted as a detection light beam, the combined light formed after being reflected by the target object is also a beam of light. Therefore, in one example, Figure 7As shown, the FMCW laser radar may also include a mode demultiplexer 600 and a second mode converter 700. The mode demultiplexer 600 is used to receive the echo light and demultiplex the echo light mode into the first echo light and the second echo light. Here, it is worth noting that the first echo light is formed by the first detection light being reflected by the target object, and the second echo light is formed by the second detection light being reflected by the target object. At this time, the first echo light is a non-fundamental mode optical signal, so the second mode converter 700 is required to perform mode conversion on it. The second mode converter 700 can be arranged between the mode demultiplexer 600 and the photoelectric detection module 200. The second mode converter 700 can convert the first echo light into a fundamental mode optical signal, so that the photoelectric detection module 200 can perform beat frequency processing on the first echo light and the first local oscillation light. In this way, the FMCW laser radar provided in the embodiment of the present application can also perform mode demultiplexing on a beam of combined light formed after reflection to form a first echo light and a second echo light corresponding to the first light source module 101 and the second light source module 102, and the performance of the mode demultiplexer 600 is not limited by environmental changes, and the mode demultiplexing process is also insensitive to wavelength. In this way, the reliability of the mode demultiplexing of a beam of light by the mode demultiplexer 600 is guaranteed, thereby ensuring the actual detection effect of the FMCW laser radar. At the same time, by setting the second mode converter 700 to perform mode conversion on the first echo light, the mode of the first echo light is made the same as that of the first local oscillation light, thereby ensuring the uniformity of the signal received by the photoelectric detection module 200, that is, ensuring the reliability of the beat frequency of the echo light and the local oscillation light at the photoelectric detection module 200, thereby further ensuring the actual detection effect of the FMCW laser radar.

[0074] In order to receive the first echo light and the second echo light respectively, in one example, Figure 8As shown, the photoelectric detection module 200 may include a first photoelectric detection module 201 and a second photoelectric detection module 202. The first photoelectric detection module 201 is used to receive the first local oscillation light and the first echo light outputted via the second mode converter 700, and to perform a beat frequency on the first local oscillation light and the first echo light. The second photoelectric detection module 202 is used to receive the second local oscillation light and the second echo light, and to perform a beat frequency on the second local oscillation light and the second echo light. The first local oscillation light, the first echo light, the second local oscillation light, and the second echo light are respectively subjected to a beat frequency processing by the independent first photoelectric detection module 201 and the second photoelectric detection module 202, thereby obtaining an electrical signal related to the beat frequency signal corresponding to the first light source module 101 and the second light source module 102, so that the subsequent signal processing module 300 can obtain the frequencies of the above two beat frequency signals according to the above electrical signals, thereby ensuring the beat frequency reliability. In addition, as mentioned above, the photoelectric detection module 200 can also be a single photoelectric detector, which simultaneously receives the first local oscillation light, the first echo light, the second local oscillation light and the second echo light, so that the first local oscillation light and the first echo light beat each other, and the second local oscillation light and the second echo light beat each other. The photoelectric detector is used to perform photoelectric conversion on the beat signal to obtain an electrical signal corresponding to the two beat signals.

[0075] The above is an implementation method in which the first light source module 101 and the second light source module 102 correspond to independent light splitting modules, that is, the first light source module 101 generates the first detection light and the first local oscillation light through the first light splitting module 1012, and the second light source module 102 generates the second detection light and the second local oscillation light through the second light splitting module 1022. The FMCW laser radar provided in the embodiment of the present application can also perform light splitting processing on the optical signal through a beam splitting module. In one example, Fig. 9As shown, the FMCW laser radar may include a first light source module 101, a second light source module 102, a first mode converter 400, a mode multiplexer 500, and a beam splitter module 800. In this example, the first light source module 101 generates a first light signal, and the second light source module 102 generates a second light signal. Both the first light signal and the second light signal are fundamental mode light signals, and the wavelengths of the first light signal and the second light signal are different. In this example, the first mode converter 400 is used to receive the first light signal and convert the first light signal mode into a non-fundamental mode light signal. In this example, the mode multiplexer 500 is used to receive the second light signal and the first light signal outputted via the first mode converter 400, and mode multiplex them into a beam of multiplexed light signal. At this time, the beam splitter module 800 is used to receive the multiplexed light signal and split it to obtain detection light and local oscillator light. The detection light is used to detect the target object. It is worth mentioning here that the detection light at this time includes the first detection light and the second detection light, the first detection light is the part of the first light signal, and the second detection light is the part of the second light signal, and the local oscillation light at this time includes the first local oscillation light and the second local oscillation light, the first local oscillation light is the part of the first light signal, and the second local oscillation light is the part of the second light signal.

[0076] Since the first light source module 101 and the second light source module 102 correspond to the same beam splitting module 800, that is, the splitting ratios are the same, through a beam splitting module 800, the corresponding optical signals of the first light source module 101 and the second light source module 102 can be split with the same proportion, thereby ensuring the accuracy and reliability of the beam splitting.

[0077] In this example, since the split detection light and the local oscillator light both include the first optical signal of the non-fundamental mode, it is necessary not only to demultiplex and mode-convert demultiplex the echo signal corresponding to the detection light, but also to demultiplex and mode-convert demultiplex the local oscillator light. Fig.10As shown, the FMCW laser radar may also include a first mode demultiplexer 900, a second mode demultiplexer 1000, a second mode converter 700, and a third mode converter 1100. The first mode demultiplexer 900 is used to receive the echo light corresponding to the detection light, and mode-demultiplex it into the first echo light and the second echo light. The first echo light is formed by the first detection light reflected by the target object, and the second echo light is formed by the second detection light reflected by the target object. At this time, the first echo light is a non-fundamental mode optical signal, so it needs to be mode-converted. In this example, the second mode converter 700 can be arranged between the first mode demultiplexer 900 and the photoelectric detection module 200, and is used to receive the first echo light and mode-convert it into a fundamental mode optical signal. The second mode demultiplexer 1000 is used to receive the local oscillation light, and mode-demultiplex it into the first local oscillation light and the second local oscillation light. At this time, the first local oscillation light is a non-fundamental mode optical signal, so it needs to be mode converted. The third mode converter 1100 can be arranged between the second mode demultiplexer 1000 and the photoelectric detection module 200, and is used to receive the first local oscillation light and convert the mode into a fundamental mode optical signal. In this way, the photoelectric detection module 200 can receive the first local oscillation light, the second local oscillation light, the second echo light output by the third mode converter 1100, and the first echo light output by the second mode converter 700, which are all fundamental modes, thereby ensuring the uniformity of the signals received by the photoelectric detection module 200.

[0078] In this way, the local oscillator light and the echo light can be demultiplexed and demultiplexed by the first mode demultiplexer 900 and the second mode demultiplexer 1000, and the performance of the first mode demultiplexer 900 and the second mode demultiplexer 1000 is not limited by environmental changes, and the mode demultiplexing process is not sensitive to the wavelength. In this way, the reliability of the mode demultiplexing of the local oscillator light and the echo light by the first mode demultiplexer 900 and the second mode demultiplexer 1000 is guaranteed, thereby ensuring the actual detection effect of the FMCW laser radar. At the same time, by setting the second mode converter 700 and the third mode converter 1100, the first echo light and the first local oscillator light can be mode-converted, so that the mode of the first echo light is the same as that of the second echo light, and the mode of the first local oscillator light is the same as that of the second local oscillator light, thereby ensuring the uniformity of the signal received by the photoelectric detection module 200, that is, ensuring the beat frequency reliability of the photoelectric detection module 200, thereby further ensuring the actual detection effect of the FMCW laser radar.

[0079] In order to improve the integration of FMCW laser radar, and then improve the reliability of FMCW laser radar, and at the same time facilitate the miniaturization of FMCW laser radar, optionally, the mode multiplexer 500, the first mode converter 400, the beam splitting module 800 and the photoelectric detection module 200 can be integrated into the same optical chip, reducing the individual occupied area of ​​these devices, thereby ensuring the miniaturization of FMCW laser radar. Here, it is worth noting that other devices can also be integrated on the chip, for example, the first mode demultiplexer 900, the second mode demultiplexer 1000, the second mode converter 700 and the third mode converter 300, etc., and this application does not make specific restrictions on this.

[0080] In this example, it can be understood that if Fig.11 As shown, the photoelectric detection module 200 may also include a first photoelectric detection module 201 and a second photoelectric detection module 202. In this example, the first photoelectric detection module 201 is used to receive the first echo light outputted via the second mode converter 700, and the first local oscillation light outputted via the third mode converter 1100; the second photoelectric detection module 202 is used to receive the second echo light outputted via the first mode demultiplexer 900, and the second local oscillation light outputted via the second mode demultiplexer 1000. In this way, the first local oscillation light, the first echo light, the second local oscillation light, and the second echo light are subjected to beat frequency processing respectively by the independent first photoelectric detection module 201 and the second photoelectric detection module 202, thereby obtaining an electrical signal related to the beat frequency signal corresponding to the first light source module 101 and the second light source module 102, so that the subsequent signal processing module 300 can obtain the device of the frequency of the above two beat frequency signals according to the above electrical signal, thereby ensuring the beat frequency reliability.

[0081] In summary, the FMCW laser radar using dual lasers provided in the embodiment of the present application can mode-multiplex the detection light through a mode multiplexer, and can mode-demultiplex the combined light and the local oscillator light through a mode demultiplexer to meet the use requirements of the FMCW laser radar. Moreover, the performance of the mode multiplexer and the mode demultiplexer is not limited by environmental changes, and the mode multiplexing and demultiplexing processes are not limited by wavelength changes. In this way, the reliability of mode multiplexing and demultiplexing of the mode multiplexer and the mode demultiplexer is guaranteed, thereby ensuring the actual detection effect of the FMCW laser radar.

[0082] In one example, if Fig.12As shown, the FMCW laser radar provided in the embodiment of the present application may also include an optical amplifier module 1200. Along the transmission direction of the detection light, the optical amplifier module 1200 is located downstream of the beam splitter module 800, and is used to receive the detection light output by the beam splitter module 800 and amplify the detection light to improve the detection capability of the detection light and ensure the detection effect of the FMCW laser radar. Optionally, the optical amplifier module 1200 can be any device that can amplify an optical signal, such as at least one of an optical fiber amplifier and a semiconductor optical amplifier.

[0083] In one example, if Fig.13 As shown, the FMCW laser radar provided in the embodiment of the present application may also include a scanning module 1300. Along the transmission direction of the detection light, the scanning module 1300 is located downstream of the optical amplification module 1200. The scanning module 1300 is used to reflect the detection light so that the detection light can be emitted outside the FMCW laser radar.

[0084] Here, it is worth noting that the scanning module 1300 can rotate relative to the shell of the FMCW laser radar so that the detection light can form a detection field of view outside the FMCW laser radar to detect the target object. For example, the scanning module 1300 may include a one-dimensional galvanometer to achieve one-dimensional scanning, or include a two-dimensional galvanometer to achieve two-dimensional scanning, or include a one-dimensional galvanometer and a multi-faceted rotating mirror to achieve two-dimensional scanning. The present application does not specifically limit the specific structure of the scanning module 1300. In addition, the scanning module 1300 is also used to receive a combined wave echo signal formed by the target object reflecting the combined wave detection signal, and transmit the combined wave echo signal to the photoelectric detection module 200.

[0085] In one example, if Fig.14 As shown, the FMCW laser radar provided in the embodiment of the present application may also include a transceiver module 1400. Along the transmission direction of the detection light, the transceiver module 1400 may be located downstream of the optical amplification module 1200. The transceiver module 1400 is used to receive the detection light and send it to the scanning module 1300. The transceiver module 1400 realizes the separation of the detection light path and the echo light path. The echo signal will not return to the light source device 100 along the original light path, but will flow from another port to the photoelectric detection module 200, thereby ensuring the transmission accuracy and reliability of the detection light and the echo light.

[0086] Optionally, the transceiver module 1400 may be a polarization splitter, an optical circulator, or a module integrating a transmitting waveguide and a receiving waveguide, etc., and the present application does not impose any specific limitation on this.

[0087] It should be noted here that the above is an exemplary introduction to the FMCW laser radar provided in the embodiment of the present application. Technicians can delete, replace or add new devices according to actual conditions. This application does not make any specific restrictions on this.

[0088] The embodiment of the present application also provides a movable device, which includes the FMCW laser radar in the above embodiment and a movable device body, and the FMCW laser radar is mounted on the device body. The beneficial effects that can be achieved by the movable device include the beneficial effects that can be achieved by the above FMCW laser radar, which will not be described in detail.

[0089] Through the description of the above implementation methods, technical personnel in the relevant field can understand that for the convenience and simplicity of description, only the division of the above-mentioned functional modules is used as an example. In actual applications, the above-mentioned functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above.

[0090] In the embodiments provided in the present application, it should be understood that the disclosed devices can be implemented in other ways. For example, the device embodiments described above are only schematic, for example, the division of modules or units is only a logical function division, and there may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another device, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0091] The above contents are only specific implementation methods of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A FMCW laser radar, characterized in that: include: A first light source module is used to generate a first detection light and a first local oscillation light, wherein the first detection light and the first local oscillation light are both fundamental mode optical signals; A second light source module is used to generate a second detection light and a second local oscillation light, wherein the second detection light and the second local oscillation light are both fundamental mode light signals, and the first detection light and the second detection light have different wavelengths; A first mode converter, used for receiving the first detection light and converting the mode into a non-fundamental mode optical signal; as well as The mode multiplexer is used to receive the second detection light and the first detection light outputted via the first mode converter, and mode-multiplex them into a beam of detection light for output to detect the target object.

2. The FMCW laser radar according to claim 1, characterized in that: Also includes: a mode demultiplexer, configured to receive the echo light and mode-demultiplex it into a first echo light and a second echo light, wherein the first echo light is formed by the first detection light being reflected by the target object, and the second echo light is formed by the second detection light being reflected by the target object; A second mode converter, disposed between the mode demultiplexer and the photoelectric detection module, for receiving the first echo light and converting the mode into a fundamental mode optical signal; as well as The photoelectric detection module is used to receive the first local oscillation light, the second local oscillation light, the second echo light, and the first echo light outputted via the second mode converter.

3. The FMCW laser radar according to claim 2, characterized in that: The photoelectric detection module comprises: a first photoelectric detection module, configured to receive the first local oscillation light and the first echo light outputted by the second mode converter; and The second photoelectric detection module is used to receive the second local oscillation light and the second echo light.

4. The FMCW laser radar according to claim 2, characterized in that: The first light source module comprises: A first laser, configured to generate a first source optical signal of a fundamental mode; and The first light splitting module is used to receive the first source light signal and split it into at least the first detection light and the first local oscillator light.

5. The FMCW laser radar according to claim 4, characterized in that: The second light source module comprises: a second laser for generating a second source optical signal of a fundamental mode; and The second light splitting module is used to receive the second source light signal and split it into at least the second detection light and the second local oscillation light.

6. The FMCW laser radar according to claim 5, characterized in that: The FMCW laser radar also includes a first nonlinear calibration module and a second nonlinear calibration module; The first optical splitter module is used to receive the first source light signal and split it into at least the first detection light, the first local oscillator light and the first calibration light. The first nonlinear calibration module includes a first optical splitter, a first optical delay line and a first photoelectric detection component. The first optical splitter is connected to the first optical splitter module to receive the first calibration light and split it into a first calibration signal and a second calibration signal. The first photoelectric detection component is used to receive the first calibration signal and the second calibration signal. At least one output end of the first optical splitter is connected to the first photoelectric detection component via the first optical delay line so that the optical path of the first calibration signal and the second calibration signal are different. The second spectroscopic module is used to receive the second source light signal and split it into at least the second detection light, the second local oscillator light and the second calibration light. The second nonlinear calibration module includes a second spectrometer, a second optical delay line and a second photodetection component. The second spectrometer is connected to the second spectrometer module to receive the second calibration light and split it into a third calibration signal and a fourth calibration signal. The second photodetection component is used to receive the third calibration signal and the fourth calibration signal. At least one output end of the second spectrometer is connected to the second photodetection component via the second optical delay line so that the optical path of the third calibration signal and the fourth calibration signal are different.

7. The FMCW laser radar according to claim 3, characterized in that: The mode multiplexer, the first mode converter, the first light splitting module, the second light splitting module and the photoelectric detection module are integrated into the same optical chip.

8. The FMCW laser radar according to claim 3, characterized in that: Also includes an optical amplification module; The optical amplification module is used to receive the detection light and amplify the detection light.

9. The FMCW laser radar according to claim 3, characterized in that: Also includes scanning module; The scanning module is used to reflect the detection light so that the detection light is emitted outside the laser radar. The scanning module can rotate relative to the shell of the laser radar so that the detection light forms a detection field of view outside the laser radar.

10. A FMCW laser radar, characterized in that: include: A first light source module, used to generate a first light signal, wherein the first light signal is a fundamental mode light signal; A second light source module, used for generating a second optical signal, wherein the second optical signal is a fundamental mode optical signal, and the first optical signal and the second optical signal have different wavelengths; A first mode converter, configured to receive the first optical signal and perform mode conversion into a non-fundamental mode optical signal; as well as A mode multiplexer, configured to receive the second optical signal and the first optical signal outputted via the first mode converter, and mode-multiplex the received optical signal into a multiplexed optical signal; A beam splitting module is used to receive the multiplexed optical signal and split it to obtain detection light and local oscillation light. The detection light is used to detect the target object. The detection light includes a first detection light and a second detection light. The first detection light is a part of the first optical signal, and the second detection light is a part of the second optical signal. The local oscillation light includes a first local oscillation light and a second local oscillation light. The first local oscillation light is a part of the first optical signal, and the second local oscillation light is a part of the second optical signal.

11. The FMCW laser radar according to claim 10, characterized in that: Also includes: A first mode demultiplexer is used to receive the echo light and mode-demultiplex it into a first echo light and a second echo light, wherein the first echo light is formed by the first detection light being reflected by the target object, and the second echo light is formed by the second detection light being reflected by the target object; A second mode converter, disposed between the first mode demultiplexer and the photoelectric detection module, for receiving the first echo light and converting the mode into a fundamental mode optical signal; A second mode demultiplexer, used for receiving the local oscillator light and mode demultiplexing the local oscillator light into a first local oscillator light and a second local oscillator light; A third mode converter, disposed between the second mode demultiplexer and the photoelectric detection module, for receiving the first local oscillation light and converting the first local oscillation light into a fundamental mode light signal; as well as The photoelectric detection module is used to receive the first local oscillation light, the second local oscillation light, the second echo light, and the first echo light outputted via the second mode converter.

12. The FMCW laser radar according to claim 11, characterized in that: The photoelectric detection module comprises: a first photoelectric detection module, configured to receive the first echo light outputted by the second mode converter and the first local oscillation light outputted by the third mode converter; and The second photoelectric detection module is used to receive the second echo light outputted by the first mode demultiplexer and the second local oscillation light outputted by the second mode demultiplexer.

13. The FMCW laser radar according to claim 12, characterized in that: The mode multiplexer, the first mode converter, the beam splitting module and the photoelectric detection module are integrated into the same optical chip.

14. A movable device, characterized in that: It comprises the FMCW laser radar as described in any one of claims 1 to 13 and a movable device body, wherein the FMCW laser radar is mounted on the device body.

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