All-solid-state laser radar system

Abstract

The invention relates to the technical field of laser radars, in particular to an all-solid-state laser radar system which comprises a wavelength selection frequency modulation laser and a photon chip. The wavelength selection frequency modulation laser is used for emitting N pieces of frequency modulation light with different wavelength ranges, and N is an integer greater than 1; the photon chip comprises an optical switch array, the optical switch array is provided with M light output ends, M is an integer greater than 1, each light output end is connected with an emergent waveguide, and the optical switch array is used for receiving N pieces of frequency-modulated light and enabling each piece of frequency-modulated light to be emergent along the M emergent waveguides so as to form two-dimensional scanning array light. According to the all-solid-state laser radar system, two-dimensional light beam scanning can be achieved under the condition that a rotating part is not arranged, the service life of the all-solid-state laser radar system is not limited by the rotating part, the service life of the laser radar is prolonged, more detection points exist in unit time, and high resolution can be obtained.

Description

Technical Field

[0001] This invention relates to the field of lidar technology, and specifically to an all-solid-state lidar system. Background Technology

[0002] LiDAR can provide autonomous driving systems with faster and higher-resolution environmental information, thus playing a crucial role in autonomous driving or advanced driver assistance applications. LiDAR typically measures distance to a target using the Time-of-Flight (TOF) method, which calculates distance by multiplying the speed of light by the time the light pulse travels between the target and the LiDAR. However, TOF LiDAR can generate severe interference when detecting signals from other LiDAR systems, leading to target misidentification in autonomous driving systems and malfunctions in driver assistance functions. Frequency Modulated Continuous Wave (FMCW) LiDAR has emerged to address this issue. FMCW LiDAR measures distance based on beat time and offers superior performance, including high resolution, high detection sensitivity, and the ability to simultaneously acquire the target's speed.

[0003] To achieve two-dimensional beam scanning with a large field of view, FMCW lidar is typically a hybrid solid-state lidar consisting of a single-line frequency-modulated continuous-wave laser and a rotating component. The rotating component is either a two-dimensional rotating mirror or a two-dimensional mechanical micro-mirror (MEMS). However, the lifespan of the lidar is limited by the rotating component. Summary of the Invention

[0004] In view of this, the present invention provides an all-solid-state lidar system to extend the lifespan of lidar.

[0005] This invention provides an all-solid-state lidar system, comprising a wavelength selective frequency-modulated laser and a photonic chip; the wavelength selective frequency-modulated laser is used to emit N frequency-modulated lights with different wavelength ranges, where N is an integer greater than 1; the photonic chip includes an optical switch array, the optical switch array having M optical output terminals, where M is an integer greater than 1, each of the optical output terminals being connected to an outgoing waveguide, the optical switch array being used to receive the N frequency-modulated lights and enable each frequency-modulated light to be emitted along the M outgoing waveguides to form a two-dimensional scanning array light.

[0006] The aforementioned all-solid-state lidar system can emit two-dimensional scanning array light without rotating components, thus achieving two-dimensional beam scanning with a large field of view. Its lifespan is not limited by rotating components, which helps extend the lidar's lifespan. This all-solid-state lidar system utilizes an optical switch array to control the frequency of light emitted from the output waveguide, resulting in a greater number of detection points per unit time compared to rotating components, thereby achieving higher resolution.

[0007] In some alternative implementations, a power attenuator is connected to the middle section of each of the outgoing waveguides to reduce the degree of crosstalk between the outgoing waveguides, which is beneficial to improving detection accuracy.

[0008] In some alternative implementations, the optical switch array includes multiple cascaded optical switch devices.

[0009] In some alternative implementations, the optical switching device includes a thermo-optical switching device or an electro-optical switching device.

[0010] In some optional embodiments, the photonic chip further includes a first beam splitter, a second beam splitter, and a first mixer; the first beam splitter is used to receive the N frequency-modulated beams, a first output terminal of the first beam splitter is connected to the input terminal of the first mixer, and a second output terminal of the first beam splitter is connected to the input terminal of the second beam splitter; the first output terminal of the second beam splitter is connected to the optical input terminal of the optical switch array, and a second output terminal of the second beam splitter is connected to the input terminal of the first mixer; the all-solid-state lidar system further includes a first photodetector and a control and analysis unit, the input terminal of the first photodetector is connected to the output terminal of the first mixer, and the output terminal of the first photodetector is connected to the input terminal of the control and analysis unit.

[0011] In some alternative implementations, the wavelength-selective frequency-modulated laser and / or the first photodetector are integrated onto the photonic chip.

[0012] In some optional implementations, the first control terminal of the control analysis unit is connected to the optical switch array to control the switching of optical channels in the optical switch array.

[0013] In some optional implementations, the photonic chip further includes a third beam splitter, a fourth beam splitter, and a second mixer; the all-solid-state lidar system further includes a second photodetector; the input of the third beam splitter is connected to the transmitter of the wavelength selectively modulated laser; the first output of the third beam splitter is connected to the input of the first beam splitter; the second output of the third beam splitter is connected to the input of the fourth beam splitter; both the first and second outputs of the fourth beam splitter are connected to the input of the second mixer; the output of the second mixer is connected to the input of the second photodetector; the output of the second photodetector is connected to the input of the control and analysis unit; and the second control terminal of the control and analysis unit is connected to the wavelength selectively modulated laser to adjust the modulation frequency and modulation linearity of the wavelength selectively modulated laser.

[0014] In some alternative implementations, the second photodetector is integrated onto the photonic chip.

[0015] In some alternative implementations, the all-solid-state lidar system further includes a collimating lens located on the side of the photonic chip and close to the light-emitting end of the photonic chip. Attached Figure Description

[0016] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of an all-solid-state lidar system according to an embodiment of the present invention.

[0018] Figure 2 This is a dot matrix diagram of a two-dimensional scan of an all-solid-state lidar system according to an embodiment of the present invention.

[0019] Figure 3 This is a dot matrix diagram of a single outgoing waveguide for outgoing unmodulated light according to an embodiment of the present invention.

[0020] Figure 4 This is a schematic diagram of the emitted laser of a wavelength selective frequency modulated laser according to an embodiment of the present invention.

[0021] Explanation of reference numerals in the attached figures: 1- Wavelength-selective frequency-modulated laser; 2- Photonic chip; 21- Optical switch array; 211- Optical switch device; 22- Outgoing waveguide; 23- First beam splitter; 24- Second beam splitter; 25- First mixer; 26- Third beam splitter; 27- Fourth beam splitter; 28- Second mixer; 3- First photodetector; 4- Second photodetector; 5- Control and analysis unit; 51- Signal processing module; 52- Host computer; 6- Collimating lens; 7- Target under test. Detailed Implementation

[0022] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the term "connection" should be interpreted broadly. For example, it can refer to a fixed connection, a detachable connection, or an integral connection; it can refer to a direct connection or an indirect connection through an intermediate medium; it can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0024] In the description of this invention, it should be noted that the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0025] As described in the background section, FMCW lidar is typically a hybrid solid-state lidar consisting of a single-line frequency-modulated continuous-wave laser and a rotating component to achieve two-dimensional beam scanning with a large field of view. The rotating component is either a two-dimensional rotating mirror or a two-dimensional mechanical micro-mirror (MEMS). The two-dimensional rotating mirror consists of a polygonal prism rotating along the horizontal axis and a pendulum mirror oscillating along the vertical axis. The continuously rotating polygonal prism along the horizontal axis enables horizontal scanning, while the pendulum mirror oscillating along the vertical axis changes the vertical scanning direction of the laser. The core of the two-dimensional mechanical micro-mirror is a centimeter-scale micromirror. Using a cantilever beam, the micromirror can achieve high-speed periodic motion along both the horizontal and vertical axes. By controlling the deflection angle of the micromirror, the laser emission direction can be changed, thereby altering the scanning path.

[0026] A single-line frequency-modulated continuous-wave laser outputs only a single laser beam. The periodic rotation of a rotating component allows this beam to sweep across the entire field of view along a fixed trajectory, achieving a large field-of-view two-dimensional beam scan. However, because a single-line frequency-modulated continuous-wave laser outputs only a single beam, the number of scan lines is limited. Multiple scans by the rotating component are required to stitch together a two-dimensional / three-dimensional image, resulting in a small number of detection points per unit time and difficulty in achieving high resolution. To compensate for this, the rotation speed of the rotating component needs to be increased to raise the scanning frequency and thus increase the detection point density. However, high-frequency scanning accelerates the mechanical wear of the rotating component, shortening its lifespan. Furthermore, the high-frequency rotation requires the drive component to consume more electrical energy, potentially leading to increased heat generation and affecting the overall reliability of the rotating component. Ultimately, the lifespan of the lidar is limited by the rotation component.

[0027] Based on this, refer to Figure 1 This invention provides an all-solid-state lidar system, including a wavelength selective frequency modulated laser 1 and a photonic chip 2; the wavelength selective frequency modulated laser 1 is used to emit N frequency-modulated lights with different wavelength ranges, where N is an integer greater than 1; the photonic chip 2 includes an optical switch array 21, which has M optical output terminals, where M is an integer greater than 1, and each optical output terminal is connected to an outgoing waveguide 22. The optical switch array 21 is used to receive the N frequency-modulated lights and enable each frequency-modulated light to be emitted along the M outgoing waveguides 22 to form a two-dimensional scanning array light.

[0028] The all-solid-state lidar system of this invention can emit two-dimensional scanning array light without the need for rotating components, thus enabling two-dimensional beam scanning with a large field of view. Its lifespan is not limited by rotating components, which helps extend the lidar's lifespan. This all-solid-state lidar system utilizes an optical switch array 21 to control the frequency of light emitted from the output waveguide 22, achieving a greater number of detection points per unit time compared to rotating components, resulting in higher resolution.

[0029] The mechanism by which the all-solid-state lidar system emits light from a two-dimensional scanning array is as follows: By controlling the voltage applied to the optical switch array 21, light can be emitted sequentially from M optical output terminals and even M outgoing waveguides 22; when the light enters free space from the waveguide, the emission angle satisfies Snell's law: n wg ×sinθ wg =n air ×sinθ out In the formula, n wg θ represents the refractive index of the waveguide. wg Let n represent the angle of incidence. air θ represents the refractive index of air. out The effective refractive index n represents the exit angle, due to the different wavelengths of light propagating in the waveguide.wg The difference is that the emission angle θ of light of different wavelengths is different. out They are also different; and each frequency-modulated light corresponds to a center wavelength, such as Figure 4 As shown, the center wavelengths (λ1~λ2) of N frequency-modulated lights N The light emitted from each of the M outgoing waveguides 22 corresponds to N light spots arranged along the first direction; the N groups of light spots emitted from the M outgoing waveguides 22 are arranged along the second direction, which is perpendicular to the first direction, thus forming an N×M light spot array. N corresponds to the number of lines scanned in the first direction by the all-solid-state lidar system, and M corresponds to the number of lines scanned in the second direction by the all-solid-state lidar system. Figure 2 A 20×16 beam array is shown. That is, scanning in one dimension is achieved through the dispersion effect of the waveguide, and scanning in another dimension is achieved through the modulation switching capability of the optical switch array, thus realizing two-dimensional beam scanning.

[0030] In other words, if the laser is a single-line frequency-modulated laser, it can only emit a modulated light with a modulation depth of GHz. Then, by controlling the optical switch array 21, the beam is emitted from different output waveguides 22 after passing through the optical switch array 21. That is, corresponding to M light spots arranged along the second direction, the output waveguides along the arrangement direction are CH1-CHM. Figure 3 The diagram shows the light spots corresponding to the rays emitted from the first exit waveguide CH1, the seventh exit waveguide CH7, the eighth exit waveguide CH8, and the sixteenth exit waveguide CH16, demonstrating one-dimensional beam scanning; see also... Figure 4 The above-mentioned modulated light (λ) 11 ~λ 12 ) Expanded to N modulation depths of GHz (λ) i1 ~λ i2 After frequency modulation of a fast triangular wave (i=1,2,…,N), a result is formed. Figure 2 The N×M beam array shown enables two-dimensional beam scanning. λ1~λ N Wavelength switching is used to achieve wavelength scanning, λ i1 ~λ i2 Continuous wave scanning is used to achieve distance and velocity measurement.

[0031] Specifically, the outgoing waveguide 22 extends to the end face of the photonic chip 2, and the light beam exits from the end face of the photonic chip 2 along the outgoing waveguide 22. The sequential light output from the M optical output ends helps to reduce the degree of crosstalk between the outgoing waveguides 22 and improves the detection accuracy.

[0032] N can be an integer multiple of 2, such as 32, 64, 256, 512, etc.

[0033] In some optional embodiments, the optical switch array 21 includes multiple cascaded optical switch devices 211, which can switch the transmission direction of optical signals between their different optical channels. For example, the optical switch devices can be dual-channel optical switch devices, each having one input terminal and two output terminals. The two output terminals of a dual-channel optical switch device in the previous stage are respectively connected to the input terminals of two dual-channel optical switch devices in the next stage, forming an optical switch array with a tree structure. The total number of channels in the last stage of dual-channel optical switch devices is equal to the number of outgoing waveguides M. The number of stages of dual-channel optical switch devices is adapted to the number of outgoing waveguides. Light output from a dual-channel optical switch device in the previous stage can be transmitted to two dual-channel optical switch devices in the next stage. The optical switch devices in the optical switch array can also be connected in other ways.

[0034] The optical switching devices include, but are not limited to, thermo-optical switching devices or electro-optical switching devices.

[0035] The all-solid-state lidar system also includes an optical switch driving unit, which is used to control the switching of optical channels in each optical switch device in the optical switch array.

[0036] In some optional embodiments, the photonic chip 2 may further include a first beam splitter 23, a second beam splitter 24, and a first mixer 25; the first beam splitter 23 is used to receive the N frequency-modulated beams, the first output terminal of the first beam splitter 23 is connected to the input terminal of the first mixer 25, and the second output terminal of the first beam splitter 23 is connected to the input terminal of the second beam splitter 24; the first output terminal of the second beam splitter 24 is connected to the optical input terminal of the optical switch array 21, and the second output terminal of the second beam splitter 24 is connected to the input terminal of the first mixer 25; the all-solid-state lidar system further includes a first photodetector 3 and a control and analysis unit 5, the input terminal of the first photodetector 3 is connected to the output terminal of the first mixer 25, and the output terminal of the first photodetector 3 is connected to the input terminal of the control and analysis unit 5.

[0037] The first beam splitter 23 receives the N frequency-modulated beams and splits them into local oscillator beams and probe beams. The local oscillator beams are transmitted to the first mixer 25, and the probe beams are transmitted to the optical switch array 21 via the second beam splitter 24, causing the frequency-modulated beams to exit along the outgoing waveguide 22. The return beams formed after reflection from the target 7 are transmitted sequentially through the outgoing waveguide 22 and the optical switch array 21 to the second beam splitter 24, and then to the first mixer 25 via the second beam splitter 24. In the first mixer 25, the return beams and the local oscillator beams are mixed to obtain two measurement interference beams. After coherent detection, the two measurement interference beams are converted into measurement electrical signals by the first photodetector 3. The control and analysis unit 5 analyzes and calculates the measurement electrical signals to obtain the distance to the target 7.

[0038] The control and analysis unit 5 may include a signal processing module 51 (FPGA) and a host computer 52. The output terminal of the first photodetector 3 is connected to the input terminal of the signal processing module 51. The signal processing module 51 performs data analysis and calculation based on the measured electrical signal and transmits the calculation and analysis results to the host computer 52, which outputs them in the form of point cloud.

[0039] In some optional embodiments, the first control terminal of the control and analysis unit 5 is connected to the optical switch array 21 to control the switching of optical channels in each optical switch device 211 of the optical switch array 21. That is, the optical switch driving unit is integrated in the control and analysis unit 5. For example, the optical switch driving unit is integrated in the signal processing module 51, which has control functions.

[0040] In some optional embodiments, the wavelength-selective frequency-modulated laser 1 and / or the first photodetector 3 are integrated on the photonic chip 2. Specifically, the wavelength-selective frequency-modulated laser 1 can be heterogeneously integrated on the photonic chip 2, and the first photodetector 3 can be homogeneously integrated on the photonic chip 2. The substrate of the photonic chip 2 can be one or more of a silicon-on-insulator (SOI) platform, a silicon nitride (SiN) platform, a thin-film lithium niobate (TFLN) platform, etc.

[0041] In some optional embodiments, the photonic chip 2 further includes a third beam splitter 26, a fourth beam splitter 27, and a second mixer 28; the all-solid-state lidar system further includes a second photodetector 4; the input terminal of the third beam splitter 26 is connected to the transmitter of the wavelength selective frequency modulated laser 1; the first output terminal of the third beam splitter 26 is connected to the input terminal of the first beam splitter 23; the second output terminal of the third beam splitter 26 is connected to the input terminal of the fourth beam splitter 27; the first and second output terminals of the fourth beam splitter 27 are both connected to the input terminal of the second mixer 28; the output terminal of the second mixer 28 is connected to the input terminal of the second photodetector 4; the output terminal of the second photodetector 4 is connected to the input terminal of the control and analysis unit 5; and the second control terminal of the control and analysis unit 5 is connected to the wavelength selective frequency modulated laser 1 to regulate the modulation frequency of the wavelength selective frequency modulated laser 1.

[0042] The third beam splitter 26 receives the laser light from the wavelength-selective frequency-modulated laser 1 and splits it into a reference beam and a signal beam. The reference beam is split into two beams by the fourth beam splitter 27, which have different delay lengths and both enter the second mixer 28. In the second mixer 28, they are mixed to obtain two reference interference beams. After coherent detection, the two reference interference beams are converted into a reference electrical signal by the second photodetector 4. The control and analysis unit 5 adjusts the modulation frequency and modulation linearity of the wavelength-selective frequency-modulated laser 1 based on the analysis results of the reference electrical signal to improve the detection range and range resolution of the lidar. The signal beam is transmitted to the first beam splitter 23 and split into a local oscillator beam and a probe beam.

[0043] The photonic chip 2 also includes intermediate transmission waveguides for light conduction within the chip. For example, intermediate transmission waveguides are used for the connections between the third beamsplitter 26 and the fourth beamsplitter 27, the fourth beamsplitter 27 and the second mixer 28, the second mixer 28 and the second photodetector 4PD1, the third beamsplitter 26 and the first beamsplitter 23, the first beamsplitter 23 and the first mixer 25, the first mixer 25 and the first photodetector 3, the first beamsplitter 23 and the second beamsplitter 24, the second beamsplitter 24 and the optical switch array 21, the connection of upper and lower level optical switch devices 211, and the connection between the second beamsplitter 24 and the first mixer 25. The two intermediate transmission waveguides connecting the fourth beamsplitter 27 and the second mixer 28 have different lengths, so that the two beams entering the second mixer 28 from the fourth beamsplitter 27 have different delay lengths.

[0044] In some alternative embodiments, the second photodetector 4 is integrated onto the photonic chip 2. Specifically, the second photodetector 4 can be homogeneously integrated onto the photonic chip 2.

[0045] The third beam splitter 26, the fourth beam splitter 27, and the first beam splitter 23 may include directional couplers, Y-waveguide beam splitters, and multimode interferometers, etc.; the second beam splitter 24 may include polarization beam splitters, etc. The wavelength-selective frequency-modulated laser 1 can be a wavelength-selective frequency-modulated narrow-linewidth linear laser, which is beneficial for improving detection resolution.

[0046] In some optional embodiments, a power attenuator is connected to the middle section of each of the outgoing waveguides 22 to attenuate the power of the frequency-modulated light, thereby effectively reducing the degree of crosstalk between the outgoing waveguides 22 and improving detection accuracy. In other words, the photonic chip 2 also includes M power attenuators, and each of the outgoing waveguides 22 includes a first sub-waveguide and a second sub-waveguide. The input end of the first sub-waveguide is connected to the optical output end of the optical switch array 21 in a one-to-one correspondence, the output end of the first sub-waveguide is connected to the input end of the power attenuator in a one-to-one correspondence, the output end of the power attenuator is connected to the input end of the second sub-waveguide in a one-to-one correspondence, and the output end of the second sub-waveguide emits a light beam.

[0047] Specifically, during the transmission of the frequency-modulated light along the m-th outgoing waveguide, the attenuation value of the power attenuator in the m-th outgoing waveguide is adjusted to the minimum, while the attenuation values ​​of the power attenuators in other outgoing waveguides are adjusted to the maximum. Here, m is an integer greater than or equal to 1 and less than or equal to M, to reduce the risk of crosstalk caused by light leakage from other outgoing waveguides. For example, Table 1 shows... Figure 1 The crosstalk level between the output waveguides of the all-solid-state lidar system is given, where M is 16, and the output waveguides are arranged sequentially as CH1-CH16 along the direction of the output waveguides.

[0048] Table 1: Crosstalk between outgoing waveguides

[0049] Therefore, it can be seen that the power attenuator ensures that the absolute value of the maximum crosstalk between each outgoing waveguide 22 is greater than 53dB, while without the power attenuator, the absolute value of the maximum crosstalk between each outgoing waveguide 22 is less than 35dB. The larger the absolute value of the maximum crosstalk, the weaker the crosstalk between waveguides and the better the signal isolation effect. This shows that the power attenuator can effectively reduce the degree of crosstalk between each outgoing waveguide 22.

[0050] In some optional embodiments, the all-solid-state lidar system further includes a collimating lens 6, which is located on the side of the photonic chip 2 and close to the light emitting end of the photonic chip 2. The light emitted from the photonic chip 2 is collimated by the collimating lens 6 and then emitted into the environment for detection. The reflected light from the target 7 enters the outgoing waveguide 22 after passing through the collimating lens 6.

[0051] Optical Phased Array (OPA) lidar consists of an array of multiple laser emitting units. The emission angle of the laser is changed by adjusting the phase difference between the various laser emitting units in the array. Although OPA lidar can achieve two-dimensional beam scanning with a large field of view without rotating components, the presence of a grating requires the array unit size to be controlled at the nanometer level. This significantly increases the impact of manufacturing process deviations, making it difficult to guarantee the phase difference and thus affecting the scanning effect. In contrast, the all-solid-state lidar system of this invention does not require a grating, thereby reducing the precision requirements for photonic chip fabrication and effectively minimizing the impact of manufacturing process deviations on the scanning effect.

[0052] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. An all-solid-state lidar system, characterized in that, include: A wavelength-selective frequency-modulated laser, wherein the wavelength-selective frequency-modulated laser is used to emit N frequency-modulated beams with different wavelength ranges, where N is an integer greater than 1; A photonic chip, comprising an optical switch array having M optical output terminals, where M is an integer greater than 1, each optical output terminal being connected to an outgoing waveguide, the optical switch array being used to receive N frequency-modulated beams and enable each frequency-modulated beam to be emitted along the M outgoing waveguides to form a two-dimensional scanning array light.

2. The all-solid-state lidar system according to claim 1, characterized in that, Each of the outgoing waveguides is connected to a power attenuator in the middle section.

3. The all-solid-state lidar system according to claim 1, characterized in that, The optical switch array includes multiple cascaded optical switch devices.

4. The all-solid-state lidar system according to claim 3, characterized in that, The optical switching device includes a thermo-optical switching device or an electro-optical switching device.

5. The all-solid-state lidar system according to claim 1, characterized in that, The photonic chip further includes a first beam splitter, a second beam splitter, and a first mixer; the first beam splitter is used to receive the N frequency-modulated beams, the first output terminal of the first beam splitter is connected to the input terminal of the first mixer, and the second output terminal of the first beam splitter is connected to the input terminal of the second beam splitter; the first output terminal of the second beam splitter is connected to the optical input terminal of the optical switch array, and the second output terminal of the second beam splitter is connected to the input terminal of the first mixer. The all-solid-state lidar system further includes a first photodetector and a control and analysis unit. The input terminal of the first photodetector is connected to the output terminal of the first mixer, and the output terminal of the first photodetector is connected to the input terminal of the control and analysis unit.

6. The all-solid-state lidar system according to claim 5, characterized in that, The wavelength-selective frequency-modulated laser and / or the first photodetector are integrated on the photonic chip.

7. The all-solid-state lidar system according to claim 5, characterized in that, The first control terminal of the control and analysis unit is connected to the optical switch array to control the switching of optical channels in the optical switch array.

8. The all-solid-state lidar system according to any one of claims 5 to 7, characterized in that, The photonic chip further includes a third beam splitter, a fourth beam splitter, and a second mixer. The all-solid-state lidar system also includes a second photodetector. The input of the third beam splitter is connected to the transmitter of the wavelength selectively modulated laser. The first output of the third beam splitter is connected to the input of the first beam splitter. The second output of the third beam splitter is connected to the input of the fourth beam splitter. The first and second outputs of the fourth beam splitter are both connected to the input of the second mixer. The output of the second mixer is connected to the input of the second photodetector. The output of the second photodetector is connected to the input of the control and analysis unit. The second control terminal of the control and analysis unit is connected to the wavelength selectively modulated laser to adjust the modulation frequency and modulation linearity of the wavelength selectively modulated laser.

9. The all-solid-state lidar system according to claim 8, characterized in that, The second photodetector is integrated on the photonic chip.

10. The all-solid-state lidar system according to any one of claims 1 to 4, characterized in that, It also includes a collimating lens, which is located on the side of the photonic chip and close to the light emitting end of the photonic chip.

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