Laser radar system

Abstract

The invention discloses a laser radar system, and relates to the technical field of laser radars. The laser radar system comprises a silicon optical integrated circuit, a laser generating circuit, an optical scanning circuit, a scanning driving circuit, a laser driving circuit and a main control circuit. The laser generating circuit, the scanning driving circuit, the laser driving circuit and the main control circuit are arranged on different circuit boards; the main control circuit provides a laser driving signal for the laser driving circuit and provides a scanning driving signal for the scanning driving circuit; the laser driving circuit controls the laser generating circuit to emit a laser signal according to the laser driving signal; the scanning driving circuit controls the optical scanning circuit to shape a laser signal according to the scanning driving signal, transmits the laser signal to an object to be scanned, and controls the optical scanning circuit to feed back a detection optical signal detected by the object to be scanned to the silicon optical integrated circuit; the silicon optical integrated circuit provides a detection electric signal for the main control circuit; the master control circuit determines an optical scanning result. According to the invention, the measurement precision and stability of the laser radar system are improved.

Description

Technical Field

[0001] The embodiments of the present invention relate to the field of laser radar technology, and in particular to a laser radar system. Background Art

[0002] Laser detection and ranging (LiDAR) technology measures the distance and speed of target objects by emitting and receiving laser signals. It is widely used in autonomous driving, drone navigation, industrial measurement, and other fields. Frequency Modulated Continuous Wave (FMCW) LiDAR systems simultaneously measure the distance and speed of target objects by emitting laser signals whose frequency varies linearly with time, with high accuracy and strong interference resistance.

[0003] Existing FMCW lidar systems typically utilize a single integrated driver module, which provides power and modulation signals to the laser and controls the optical scanning module for beam deflection and shaping. This integrated driver module is susceptible to electromagnetic noise interference, particularly when the optical scanning module operates at high power. This noise can affect the laser's frequency stability and signal quality, thereby reducing the FMCW lidar system's measurement accuracy. Furthermore, the integrated driver module generates significant heat during operation, making it difficult to effectively dissipate heat, resulting in reduced stability of the FMCW lidar system. Summary of the Invention

[0004] The present invention provides a laser radar system, which reduces noise interference and optimizes heat dissipation performance by independently driving an optical scanning circuit and a laser generating circuit, thereby improving the measurement accuracy and stability of the laser radar system.

[0005] A first aspect of the present invention provides a laser radar system, the laser radar system comprising: a silicon photonic integrated circuit, a laser generating circuit, an optical scanning circuit, a scanning driving circuit, a laser driving circuit and a main control circuit;

[0006] The silicon photonic integrated circuit, the scan drive circuit, the laser drive circuit and the main control circuit are respectively arranged on different circuit boards; the laser generating circuit and the silicon photonic integrated circuit are arranged on the same circuit board;

[0007] The main control circuit is used to provide a laser driving signal to the laser driving circuit and a scan driving signal to the scan driving circuit;

[0008] The laser driving circuit is used to control the laser generating circuit to emit a laser signal to the silicon photonic integrated circuit according to the laser driving signal; the silicon photonic integrated circuit is used to transmit the laser signal to the optical scanning circuit;

[0009] The scanning drive circuit is used to control the optical scanning circuit to shape the laser signal and transmit it to the object to be scanned according to the scanning drive signal, and to control the optical scanning circuit to feed back the detection light signal detected by the object to be scanned to the silicon photonic integrated circuit;

[0010] The silicon photonic integrated circuit is further configured to provide a detection electrical signal to the main control circuit according to the detection optical signal;

[0011] The main control circuit is further configured to determine an optical scanning result based on the detection electrical signal.

[0012] Optionally, the laser driving circuit is specifically configured to control the frequency of the laser signal emitted by the laser generating circuit according to the scanning driving signal;

[0013] The silicon photonic integrated circuit is used to perform optical splitting processing on the laser signal and transmit the processed laser signal to the optical scanning circuit;

[0014] The silicon photonic integrated circuit is further configured to receive the detection light signal fed back by the optical scanning circuit and convert the detection light signal into a detection electrical signal.

[0015] Optionally, the silicon photonic integrated circuit includes a beam splitting unit and a photodetector;

[0016] The beam splitting unit is used to split the laser signal into a detection laser and a local oscillation laser, and transmit the detection laser to the optical scanning circuit, and transmit the local oscillation laser to the photodetector;

[0017] The photodetector is used to receive the detection light signal fed back by the optical scanning circuit, and generate a detection electrical signal according to the detection light signal and the local oscillation laser.

[0018] Optionally, the laser radar system further includes an optical detection circuit; the optical detection circuit and the silicon photonic integrated circuit are arranged in the same circuit board;

[0019] The optical detection circuit is used to amplify the detection electrical signal and output the amplified detection electrical signal to the main control circuit.

[0020] Optionally, the optical scanning circuit includes a lens assembly and a rotating mechanism; the rotating mechanism is connected to the lens assembly;

[0021] The scanning drive circuit is specifically used to control the rotating mechanism to drive the lens assembly to rotate according to the scanning drive signal, so as to adjust the optical parameters of the laser signal and the detection light signal passing through the lens assembly.

[0022] Optionally, the main control circuit includes a main control module and a modulation module;

[0023] The main control module is used to provide a modulation control signal to the modulation module;

[0024] The modulation module is used to provide the laser driving signal to the laser driving circuit according to the modulation control signal.

[0025] Optionally, the main control circuit further includes a chip control module;

[0026] The chip control module is used to obtain the working condition information of the silicon photonic integrated circuit in real time, and feed back the current working condition information of the silicon photonic integrated circuit to the main control module;

[0027] The main control module is further configured to control the provision of the modulation control signal to the modulation module and the provision of the chip control signal to the chip control module according to current operating condition information of the silicon photonic integrated circuit;

[0028] The chip control module is further configured to adjust the operating state of the silicon photonic integrated circuit according to the chip control signal.

[0029] Optionally, the main control circuit further includes an analog-to-digital conversion module and a storage module;

[0030] The analog-to-digital conversion module is used to convert the detection electrical signal into a digital detection signal;

[0031] The main control module is specifically configured to determine the optical scanning result according to the digital detection signal, and control the digital detection signal and the optical scanning result to be stored in the storage module.

[0032] Optionally, the main control circuit further includes a communication module;

[0033] The communication module is connected between the main control module and the external device; the communication module is used to control the external device to exchange information with the main control module.

[0034] Optionally, the laser radar system further includes: a power supply module;

[0035] The power supply module is used to respectively supply power to the silicon photonic integrated circuit, the laser generating circuit, the optical scanning circuit, the scanning driving circuit, the laser driving circuit and the main control circuit;

[0036] Wherein, the power supply module and the main control circuit are arranged in the same circuit board.

[0037] The technical solution of the present invention is to provide a silicon photonic integrated circuit, a laser generating circuit, an optical scanning circuit, a scanning drive circuit, a laser driving circuit, and a main control circuit in a laser radar system, so that the main control circuit can be used to provide a laser driving signal to the laser driving circuit and a scanning drive signal to the scanning drive circuit. As a result, the laser driving circuit can control the laser generating circuit to emit a laser signal to the silicon photonic integrated circuit according to the laser driving signal, and can further transmit the laser signal to the optical scanning circuit through the silicon photonic integrated circuit to meet the laser light source requirements of the laser radar system. At the same time, the scanning drive circuit can control the optical scanning circuit to shape the laser signal and transmit it to the object to be scanned according to the scanning drive signal, so as to scan the external space through the shaped laser signal, and control the optical scanning circuit to feed back the detection light signal detected by the object to be scanned to the silicon photonic integrated circuit, so that the silicon photonic integrated circuit can also provide a detection electrical signal to the main control circuit according to the detection light signal, and further enable the main control circuit to determine the optical scanning result according to the detection electrical signal. In addition, by placing the silicon photonic integrated circuit, scan driver circuit, laser driver circuit, and main control circuit on separate circuit boards, physical isolation is achieved between the different functional modules, avoiding mutual interference of electromagnetic signals between the different functional modules, thereby enhancing the stability and measurement accuracy of the LiDAR system. At the same time, by independently placing each functional module on a different circuit board, heat sources can be dispersed, optimizing the overall heat dissipation performance of the LiDAR system. Furthermore, by placing the laser generation circuit and the silicon photonic integrated circuit on the same circuit board, it is ensured that the laser signal can be stably and efficiently transmitted between the silicon photonic integrated circuit and the laser generation circuit.

[0038] It should be understood that the content described in this section is not intended to identify the key or important features of the embodiments of the present invention, nor is it intended to limit the scope of the present invention. Other features of the present invention will become readily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0040] Figure 1 1 is a schematic structural diagram of a laser radar system provided by an embodiment of the present invention;

[0041] Figure 2It is a structural diagram of another lidar system provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0042] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0043] It should be noted that the terms "first", "second", etc. in the description and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0044] Figure 1 FIG. 1 is a schematic structural diagram of a laser radar system provided by an embodiment of the present invention. Figure 1 As shown, the laser radar system includes: a silicon photonic integrated circuit 11, a laser generating circuit 12, an optical scanning circuit 2, a scanning driving circuit 3, a laser driving circuit 4 and a main control circuit 5; the silicon photonic integrated circuit 11, the scanning driving circuit 3, the laser driving circuit 4 and the main control circuit 5 are respectively arranged on different circuit boards; the laser generating circuit 12 and the silicon photonic integrated circuit 11 are arranged in the same circuit board; the main control circuit 5 is used to provide a laser driving signal to the laser driving circuit 4, and to provide a scanning driving signal to the scanning driving circuit 3; the laser driving circuit 4 is used to control the laser generating circuit 12 to send a laser signal to the silicon photonic integrated circuit 11 according to the laser driving signal; the silicon photonic integrated circuit 11 is used to transmit the laser signal to the optical scanning circuit 2; the scanning driving circuit 3 is used to control the optical scanning circuit 2 to shape the laser signal and transmit it to the object to be scanned according to the scanning driving signal, and to control the optical scanning circuit 2 to feed back the detection light signal detected by the object to be scanned to the silicon photonic integrated circuit 11; the silicon photonic integrated circuit 11 is also used to provide a detection electrical signal to the main control circuit 5 according to the detection light signal; the main control circuit 5 is also used to determine the optical scanning result according to the detection electrical signal.

[0045] The main control circuit 5 can be specifically understood as a control circuit for controlling the operating states of the laser drive circuit 4 and the scan drive circuit 3. Specifically, the main control circuit 5 can generate a laser drive signal and a scan drive signal according to instructions from an external device or feedback from within the lidar system, and can provide the laser drive signal to the laser drive circuit 4 and the scan drive signal to the scan drive circuit 3.

[0046] The laser generating circuit 12 can be specifically understood as a circuit for generating a laser light source of a laser radar system. For example, the laser generating circuit 12 may include a laser. After receiving the laser driving signal provided by the main control circuit 5, the laser driving circuit 4 will control the laser generating circuit 12 to emit a laser signal according to the laser driving signal. For example, the laser driving circuit 4 can use a constant current driving method to provide stable power to the laser in the laser generating circuit 12, and by adjusting the driving current or bias voltage of the laser, the laser can emit a laser signal with a low line width and a frequency that changes linearly with time. The line width of the laser signal can be, for example, 100 kHz. This enables the laser generating circuit 12 to transmit the laser signal to the silicon photonic integrated circuit 11, and further transmit the laser signal to the optical scanning circuit 2 through the silicon photonic integrated circuit 11 to meet the laser light source requirements of the laser radar system. For example, the silicon photonic integrated circuit 11 may include a silicon photonic chip.

[0047] The optical scanning circuit 2 can be specifically used to receive the laser signal emitted by the silicon photonic integrated circuit 11, and can shape the laser signal and transmit it to the object to be scanned, so as to scan the external space through the shaped laser signal. In addition, the optical scanning circuit 2 can also be used to capture the detection light signal detected by the object to be scanned, and can shape the detection light signal again and transmit it back to the silicon photonic integrated circuit 11, so that the silicon photonic integrated circuit 11 can further process the shaped detection light signal. After receiving the scanning drive signal provided by the main control circuit 5, the scanning drive circuit 3 will control the optical scanning circuit 2 to shape the laser signal and transmit it to the object to be scanned according to the scanning drive signal. For example, the scanning drive circuit 3 will control the optical scanning circuit 2 to adjust the deflection angle, focus and beam waist of the laser signal and then transmit it to the object to be scanned, so as to achieve full coverage of the external space by the laser signal, so that the laser radar system can adapt to the use scenarios of different distances to the object to be scanned, thereby improving the detection flexibility and accuracy of the laser radar system. At the same time, the scanning drive circuit 3 can also control the optical scanning circuit 2 to adjust the deflection angle, focus and beam waist of the detection light signal detected by the object to be scanned according to the scanning drive signal, and feed it back to the silicon photonic integrated circuit 11, so as to adjust the deflection angle, focus and beam waist of the detection light signal to be consistent with the deflection angle, focus and beam waist of the laser signal emitted by the optical scanning circuit 2, thereby ensuring the consistency of the outgoing light and the reflected light, and improving the transmission efficiency and signal quality of the laser signal in the lidar system.

[0048] The silicon photonic integrated circuit 11 is also used to receive the detection light signal fed back by the optical scanning circuit 2. Exemplarily, the silicon photonic integrated circuit 11 may include a photodetector capable of converting the detection light signal into a detection electrical signal and providing the detection electrical signal to the main control circuit 5 so that the main control circuit 5 can determine the optical scanning result based on the detection electrical signal. The optical scanning result includes the spatial distance and relative velocity between the object to be scanned in external space and the lidar system. It is understood that the frequency of the laser signal emitted by the silicon photonic integrated circuit 11 varies linearly with time. The frequency of the detection light signal is mixed with the frequency of the laser signal by the photodetector to generate a difference frequency electrical signal, thereby determining the spatial distance between the object to be scanned and the lidar system based on the frequency of the difference frequency electrical signal. Furthermore, radial motion of the object to be scanned will cause a frequency shift in the detection light signal. Therefore, by determining the Doppler shift of the difference frequency electrical signal generated by the photodetector, the relative velocity between the object to be scanned and the lidar system can be determined.

[0049] It is also understood that the silicon photonic integrated circuit 11, scan driver circuit 3, laser driver circuit 4, and main control circuit 5 are each disposed on a separate circuit board to achieve physical isolation between the different functional modules, thereby preventing mutual interference of electromagnetic signals between the different functional modules. Specifically, the laser driver circuit 4 uses a constant current method to drive the laser generator circuit 12. By independently configuring the laser driver circuit 4 and the scan driver circuit 3, interference from the high-frequency signal in the optical drive scanning circuit 3 on the laser driver circuit 4 is avoided, thereby ensuring the accuracy of the laser signal emitted by the laser generator circuit 12 controlled by the laser driver circuit 4. By independently configuring the scan driver circuit 3 from the optical scanning circuit 2, the noise generated by the motor and other components in the optical scanning circuit 2 when the optical scanning circuit 2 is operating at high power is prevented from affecting the high-frequency signal in the scan driver circuit 3. This ensures the accuracy of the laser signal shaping performed by the optical scanning circuit 2, thereby ensuring the accuracy of the optical scanning result determined by the main control circuit 5 based on the detected electrical signal, thereby enhancing the stability and measurement accuracy of the lidar system. At the same time, the scanning drive circuit 3 and the laser drive circuit 4 will generate a lot of heat during operation. By independently arranging each functional module on a different circuit board, the heat source can be dispersed and the concentrated accumulation of heat can be avoided, thereby optimizing the overall heat dissipation performance of the laser radar system. In addition, by independently arranging each functional module on a different circuit board, it is possible to adjust or optimize a single functional module according to different application scenarios of the laser radar system, thereby improving the flexibility and environmental adaptability of the laser radar system. In addition, by arranging the laser generating circuit 12 and the silicon photonic integrated circuit 11 on the same circuit board, the relative position between the silicon photonic integrated circuit 11 and the laser generating circuit 12 is ensured to be stable. The fixed position of the silicon photonic integrated circuit 11 and the laser generating circuit 12 ensures that the laser signal can be efficiently transmitted through the grating coupler between the silicon photonic integrated circuit 11 and the laser generating circuit 12, reducing the laser signal transmission imbalance caused by vibration or thermal expansion.

[0050] This embodiment provides a laser radar system with a silicon photonic integrated circuit, a laser generating circuit, an optical scanning circuit, a scanning driver circuit, a laser driving circuit, and a main control circuit. The main control circuit is configured to provide a laser driving signal to the laser driving circuit and a scanning driver circuit. This allows the laser driving circuit to control the laser generating circuit to emit a laser signal to the silicon photonic integrated circuit based on the laser driving signal, and further transmit the laser signal to the optical scanning circuit via the silicon photonic integrated circuit, thereby meeting the laser light source requirements of the laser radar system. Furthermore, the scanning driver circuit controls the optical scanning circuit to shape the laser signal and transmit it to the object to be scanned based on the scanning driver signal, thereby enabling scanning of the external space using the shaped laser signal. Furthermore, the optical scanning circuit controls the optical scanning circuit to feed back a detection light signal detected by the object to be scanned to the silicon photonic integrated circuit, enabling the silicon photonic integrated circuit to provide a detection electrical signal to the main control circuit based on the detection light signal, and further enabling the main control circuit to determine the optical scanning result based on the detection electrical signal. In addition, by placing the silicon photonic integrated circuit, scan driver circuit, laser driver circuit, and main control circuit on separate circuit boards, physical isolation is achieved between the different functional modules, avoiding mutual interference of electromagnetic signals between the different functional modules, thereby enhancing the stability and measurement accuracy of the LiDAR system. At the same time, by independently placing each functional module on a different circuit board, heat sources can be dispersed, optimizing the overall heat dissipation performance of the LiDAR system. Furthermore, by placing the laser generation circuit and the silicon photonic integrated circuit on the same circuit board, it is ensured that the laser signal can be stably and efficiently transmitted between the silicon photonic integrated circuit and the laser generation circuit.

[0051] Optional, Figure 2 FIG. 1 is a schematic structural diagram of another laser radar system provided by an embodiment of the present invention. Figure 2 As shown, the laser driving circuit 4 is specifically used to control the frequency of the laser signal emitted by the laser generating circuit 12 according to the scanning driving signal; the silicon photonic integrated circuit 11 is used to perform spectroscopic processing on the laser signal and transmit the processed laser signal to the optical scanning circuit 2; the silicon photonic integrated circuit 11 is also used to receive the detection light signal fed back by the optical scanning circuit 2 and convert the detection light signal into a detection electrical signal.

[0052] The laser driver circuit 4 is specifically configured to control the frequency of the laser signal emitted by the laser generating circuit 12 to the silicon photonic integrated circuit 11 according to the scanning drive signal. For example, the laser driver circuit 4 can provide stable power to the laser generating circuit 12 using a constant current drive mode. Furthermore, by adjusting the drive current or bias voltage of the laser generating circuit 12, the laser generating circuit 12 can emit a laser signal with a low linewidth and a frequency that varies linearly with time to the silicon photonic integrated circuit 11 through optical coupling, thereby improving the measurement accuracy of the lidar system.

[0053] The silicon photonic integrated circuit 11 is used to perform optical splitting processing on the laser signal provided by the laser generating circuit 12, and send the processed laser signal to the optical scanning circuit 2, so that the optical scanning circuit 2 can use the laser signal processed by the silicon photonic integrated circuit 11 to perform optical scanning. At the same time, the silicon photonic integrated circuit 11 is also used to receive the detection light signal fed back by the optical scanning circuit 2, and can convert the detection light signal into a detection electrical signal for the main control circuit 5 to process and determine the optical scanning result. Optionally, the silicon photonic integrated circuit 11 includes a beam splitting unit 111 and a photodetector 112; the beam splitting unit 111 is used to split the laser signal into detection light and local oscillator light, and send the detection light to the optical scanning circuit 2, so that the optical scanning circuit 2 shapes the detection light and emits it to the external space, and emits the local oscillator laser to the photodetector 112; the photodetector 112 is used to receive the detection laser signal fed back by the optical scanning circuit 2, and generate a detection electrical signal based on the detection light signal and the local oscillator light. In addition, the silicon photonic integrated circuit 11 may also include an optical waveguide. Specifically, after the silicon photonic integrated circuit 11 receives the laser signal provided by the laser generating circuit 12, it can first frequency modulate the laser signal through the optical waveguide, and then can split the modulated laser signal into detection light and local oscillator light through the beam splitting unit 111, and can send the detection light to the optical scanning circuit 2 through the optical waveguide, so that the optical scanning circuit 2 can shape the detection light and transmit it to the object to be scanned, thereby realizing optical scanning of the object to be scanned, and at the same time, can transmit the local oscillator light to the photodetector 112 as a reference light for subsequent optical mixing by the photodetector 112. The optical waveguide can also receive the detection light signal fed back by the optical scanning circuit 2 and send it to the photodetector 112, so that the photodetector 112 can optically mix the detection light signal with the local oscillator light to generate a detection electrical signal, and can send the detection electrical signal to the main control circuit 5 through the optical waveguide, so that the main control circuit 5 can determine the spatial distance and relative speed between the object to be scanned and the laser radar system based on the frequency and Doppler frequency shift of the detection electrical signal, thereby improving the measurement efficiency of the laser radar system. By integrating the beam splitting unit 111, the photodetector 112 and the optical waveguide into the silicon photonic integrated circuit 11, the integration of the laser radar system is improved, the volume of the laser radar system is reduced, and the stability of the laser radar system is improved.

[0054] Optional, continue to refer to Figure 2 The silicon photonic integrated circuit 11 also includes an optical detection circuit 13; the optical detection circuit 13 and the silicon photonic integrated circuit 11 are arranged in the same circuit board; the optical detection circuit 13 is used to amplify the detection electrical signal and output the amplified detection electrical signal to the main control circuit 5.

[0055] Among them, the optical detection circuit 13 is used to amplify the detection electrical signal and output the amplified detection electrical signal to the main control circuit 5, so that the main control circuit 5 can determine the spatial distance and relative speed between the object to be scanned and the laser radar system based on the frequency and Doppler frequency shift of the detection electrical signal. Exemplarily, the optical detection circuit 13 may include a transimpedance amplifier (TIA). The detection electrical signal is a weak current signal. The TIA can convert the weak current signal into a voltage signal and increase the amplitude of the voltage signal to a level suitable for subsequent processing by the main control circuit 5, thereby ensuring the quality of the electrical signal transmitted to the main control circuit 5 and improving the measurement efficiency and measurement accuracy of the laser radar system. In addition, by arranging the silicon photonic integrated circuit 11 and the optical detection circuit 13 on the same circuit board, the relative position between the silicon photonic integrated circuit 11 and the optical detection circuit 13 is ensured to be stable, the transmission path of the detection electrical signal is shortened, the parasitic capacitance and noise are reduced, and the conversion efficiency of the detection electrical signal is improved, thereby improving the stability and scene adaptability of the laser radar system.

[0056] Optional, continue to refer to Figure 2 The optical scanning circuit 2 includes a lens assembly 21 and a rotating mechanism 22; the rotating mechanism is connected to the lens assembly 21; the scanning drive circuit 3 is specifically used to control the rotating mechanism 22 to drive the lens assembly 21 to rotate according to the scanning drive signal, so as to adjust the optical parameters of the laser signal and the detection light signal passing through the lens assembly 21.

[0057] Specifically, the scanning drive circuit 3 is specifically used to control the rotation mechanism 22 to drive the lens assembly 21 to rotate according to the scanning drive signal, so as to adjust the optical parameters of the laser signal and the detection light signal passing through the lens assembly 21. Exemplarily, the optical parameters may include a deflection angle. By adjusting the deflection angle of the laser signal, a three-dimensional scan of the external space where the scanned object is located can be achieved, such as full coverage of the horizontal and vertical directions of the external space. At the same time, by adjusting the deflection angle of the detection light signal, the deflection angle of the detection light signal can be adjusted to be consistent with the deflection angle of the laser signal, thereby ensuring the consistency of the outgoing light and the reflected light, and improving the transmission efficiency and signal quality of the laser signal in the lidar system. Exemplarily, the rotation mechanism may include a mechanical frame driven by a micro-electro-mechanical system (MEMS) so as to be able to adjust the deflection angle of the lens assembly 21 according to the optical scanning control signal.

[0058] In addition, the scan drive circuit 3 can also adjust the focal length of the lens assembly 21 according to the scan drive signal to adjust the focus and beam waist of the laser signal and the detection laser signal passing through the lens assembly 21. The focus of the laser signal and the detection light signal can be specifically understood as the focal position of the laser signal and the detection light signal; the beam waist of the laser signal and the detection light signal can be specifically understood as the minimum cross-sectional diameter of the laser signal and the detection light signal. By adjusting the focus of the laser signal, the laser radar system can adapt to different detection distances; by adjusting the beam waist of the laser signal, the divergence angle of the laser signal is optimized, allowing the laser radar system to adapt to different detection scenarios, such as a laser signal with a small beam waist for long-distance high-precision detection and a laser signal with a large beam waist for long-distance wide-angle scanning. At the same time, by adjusting the focus and beam waist of the detection light signal, the focus and beam waist of the detection light signal can be adjusted to be consistent with the focus and beam waist of the laser signal, thereby ensuring the consistency of the outgoing light and the reflected light, and improving the transmission efficiency and signal quality of the laser signal in the laser radar system. Exemplarily, the lens assembly 21 may include an electrically controlled focus-adjustable lens assembly so as to be able to adjust the focal length and beam waist according to the optical scanning control signal.

[0059] The scanning driving circuit 3 adjusts the focus, beam waist and deflection angle of the laser signal detected by the lens assembly 21, so that the laser radar system can support different detection scenarios, thereby improving the scene adaptability, detection efficiency and detection accuracy of the laser radar system.

[0060] Optional, continue to refer to Figure 2 The main control circuit 5 includes a main control module 51 and a modulation module 52; the main control module 51 is used to provide a modulation control signal to the modulation module 52; the modulation module 52 is used to provide a laser driving signal to the laser driving circuit 4 according to the modulation control signal.

[0061] Specifically, the main control module 51 can generate a modulation control signal based on the frequency feedback of the laser signal in the laser radar system, so that the modulation module 52 can provide a laser drive signal to the laser drive circuit 4 according to the modulation control signal, so that the laser drive circuit 4 can use a constant current drive method to provide stable power to the laser generating circuit 12, and by adjusting the drive current or bias voltage of the laser generating circuit 12, the laser generating circuit 12 can emit a laser signal with a low linewidth and a frequency that changes linearly with time. The main control module 51 and the modulation module 52 coordinate the control of the laser drive signal provided to the laser drive circuit 4, ensuring the stability and accuracy of the laser signal emitted by the laser generating circuit 12 driven by the laser drive circuit 4, thereby improving the measurement accuracy and stability of the laser radar system.

[0062] Optional, continue to refer to Figure 2The main control circuit 5 also includes a chip control module 53; the chip control module 53 is used to obtain the working condition information of the silicon photonic integrated circuit 11 in real time, and feed back the current working condition information of the laser generator to the main control module 5; the main control module 5 is also used to control the provision of a modulation control signal to the modulation module 52 and a chip control signal to the chip control module 53 according to the current working condition information of the silicon photonic integrated circuit 11; the chip control module 53 is also used to adjust the working state of the silicon photonic integrated circuit 11 according to the chip control signal.

[0063] Specifically, the chip control module 53 is used to obtain the operating condition information of the silicon photonic integrated circuit 11 in real time. For example, the chip control module 53 can obtain the current operating temperature of the silicon photonic integrated circuit 11 in real time through the temperature sensor in the silicon photonic integrated circuit 11. The chip control module 53 can also obtain the current frequency of the laser signal emitted by the silicon photonic integrated circuit 11 in real time through the photodetector 112 in the silicon photonic integrated circuit 11. The chip control module 53 can also send the real-time obtained operating condition information of the silicon photonic integrated circuit 11 to the main control module 51, so that the main control module 51 can dynamically adjust the modulation control signal provided to the modulation module 52 and the chip control signal provided to the chip control module 53 according to the current operating condition information of the silicon photonic integrated circuit 11.

[0064] When the main control module 51 determines that there is a deviation in the current frequency of the laser signal by comparing the current frequency of the laser signal with the target frequency of the laser signal, the main control module 51 will dynamically adjust the modulation control signal provided to the modulation module 52 so that the modulation module 52 can provide the laser drive signal to the laser driving circuit 4 according to the modulation control signal, thereby enabling the laser driving circuit 4 to dynamically adjust the frequency of the laser signal emitted by the laser generating circuit 12 to correct the frequency deviation of the laser signal, thereby ensuring the stability and accuracy of the laser signal emitted by the laser generating circuit 12 driven by the laser driving circuit 4, thereby improving the measurement accuracy and stability of the lidar system. When the main control module 51 determines that the current operating temperature of the silicon photonic integrated circuit 11 is too high or too low, the main control module 5 will dynamically adjust the chip control signal provided to the chip control module 53 so that the chip control module 53 can dynamically adjust the current operating temperature of the silicon photonic integrated circuit 11 according to the chip control signal, so that the current operating temperature of the silicon photonic integrated circuit 11 can be maintained within its optimal operating temperature range. For example, when the main control module 51 determines that the current operating temperature of the silicon photonic integrated circuit 11 is too high, the chip control module 53 can reduce the temperature of the silicon photonic integrated circuit 11 through the thermoelectric cooler (TEC) in the silicon photonic integrated circuit 11 according to the chip control signal provided by the main control module 5, thereby avoiding the laser signal frequency drift caused by the current high temperature of the silicon photonic integrated circuit 11 and improving the measurement accuracy and stability of the lidar system.

[0065] Optional, continue to refer to Figure 2 The main control circuit 1 also includes an analog-to-digital conversion module 54 and a storage module 55; the analog-to-digital conversion module 54 is used to convert the detection electrical signal into a digital detection signal; the main control module 51 is specifically used to determine the optical scanning result based on the digital detection signal, and control the digital detection signal and the optical scanning result to be stored in the storage module 55.

[0066] Specifically, the analog-to-digital conversion module 54 is used to receive the detection electrical signal amplified by the TIA. The detection electrical signal is an analog voltage signal. The analog-to-digital conversion module 54 is capable of converting the detection electrical signal into a digital detection signal and transmitting the converted digital detection signal to the main control module 51. Converting the detection electrical signal into a digital detection signal by the analog-to-digital conversion module 54 reduces noise interference and facilitates the main control module 51 to determine the optical scanning result based on the digital detection signal, thereby improving the measurement accuracy of the lidar system. After receiving the digital detection signal converted by the analog-to-digital conversion module 54, the main control module 51 can extract the frequency information in the digital detection signal through a signal processing algorithm, such as a Fourier transform, thereby determining the spatial distance between the object to be scanned and the lidar system based on the frequency of the digital detection signal, and determining the relative speed between the object to be scanned and the lidar system based on the Doppler frequency shift of the digital detection signal. In addition, the main control module 51 can also control the digital detection signal and the optical scanning result to be stored in the storage module 55. That is, the storage module 55 can store the frequency information of the digital detection signal, the spatial distance between the object to be scanned and the laser radar system, and the relative speed between the object to be scanned and the laser radar system, thereby avoiding the loss of detection data of the laser radar system, supporting the subsequent real-time or offline data analysis and troubleshooting of the laser radar system, and improving the performance of the laser radar system. Exemplarily, the storage module 55 can include non-volatile memory or volatile memory, such as flash memory or random access memory (RAM).

[0067] Optional, continue to refer to Figure 2 The main control circuit 5 further includes a communication module 56 ; the communication module 56 is connected between the main control module 51 and the external device 6 ; the communication module 56 is used to control the external device 6 and the main control module 51 to perform information exchange.

[0068] Specifically, the communication module 56 serves as a communication bridge between the main control module 51 and the external device 6, capable of controlling information exchange between the external device 6 and the main control module 51. For example, the communication module 56 can transmit the optical scanning results determined by the main control module 51 to the external device 6 via a communication interface. The external device 6 can, for example, be the central processing unit of an autonomous driving system or a drone navigation module, so that the external device 6 can make real-time decisions based on the optical scanning results, such as vehicle obstacle avoidance. The communication interface of the communication module 56 can include a wired communication interface or a wireless communication interface, such as Ethernet, CAN bus, Wi-Fi, or Bluetooth. Furthermore, the communication module 56 can also receive control commands transmitted by the external device 6 via the communication interface. For example, the control commands can be for adjusting the distance, range, and angle of the optical scan. After receiving the control instruction, the communication module 56 can also transmit the control instruction to the main control module 51, so that the main control module 51 can also control the scanning drive signal provided by the scanning drive circuit 3 to the optical scanning circuit 2 according to the control instruction, so that the scanning drive circuit 3 can dynamically control the optical scanning circuit 2 to adjust the deflection angle, focus and beam waist of the laser signal to ensure that the distance, range and angle of the optical scanning can meet the detection requirements of the external device 6, so that the laser radar system can adapt to different usage scenarios and improve the performance and measurement accuracy of the laser radar system.

[0069] Optional, continue to refer to Figure 2 The laser radar system also includes a power supply module 57; the power supply module 57 is used to supply power to the silicon photonic integrated circuit 11, the laser generating circuit 12, the optical scanning circuit 2, the scanning driving circuit 3, the laser driving circuit 4 and the main control circuit 5 respectively; the power supply module 57 and the main control circuit 51 are arranged in the same circuit board.

[0070] Specifically, the power module 57 can be connected to an external power supply device, such as a vehicle battery or an industrial power supply, to receive external input power provided by the external power supply device. It is understandable that different functional modules have different power requirements. For example, the optical scanning circuit 2, the scanning driver circuit 3, and the laser driver circuit 4 require higher voltage signals for power supply, while the silicon photonic integrated circuit 11 and the main control circuit 5 require lower voltage signals for power supply. Therefore, the power module 57 can also convert the external input power into the specific power supply signals required by each functional module through internal conversion circuitry, and can provide the converted power supply signals to each functional module accordingly, thereby achieving stable power supply for the silicon photonic integrated circuit 11, the laser generating circuit 12, the optical scanning circuit 2, the scanning driver circuit 3, the laser driver circuit 4, and the main control circuit 5, ensuring the stable operation of each functional module and improving the performance and stability of the LiDAR system. In addition, the power module 57 and the main control circuit 51 are disposed on the same circuit board, that is, the power module 57 is also disposed on the circuit board where the main control circuit 5 is located, reducing the number of independent circuit boards in the LiDAR system, thereby simplifying the structure of the LiDAR system and improving the overall compactness of the LiDAR system.

[0071] It should be understood that the various forms of the processes shown above can be used to reorder, add, or delete steps. For example, the steps described in the present invention can be performed in parallel, sequentially, or in a different order, as long as the desired results of the technical solutions disclosed in the present invention can be achieved. This is not limited herein.

[0072] The above specific embodiments do not limit the scope of protection of the present invention. Those skilled in the art will appreciate that various modifications, combinations, sub-combinations, and substitutions may be made based on design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention are intended to be included within the scope of protection of the present invention.

Claims

1. A laser radar system, characterized in that: include: Silicon photonic integrated circuit, laser generating circuit, optical scanning circuit, scanning driving circuit, laser driving circuit and main control circuit; The silicon photonic integrated circuit, the scan drive circuit, the laser drive circuit and the main control circuit are respectively arranged on different circuit boards; the laser generating circuit and the silicon photonic integrated circuit are arranged on the same circuit board; The main control circuit is used to provide a laser driving signal to the laser driving circuit and a scan driving signal to the scan driving circuit; The laser driving circuit is used to control the laser generating circuit to emit a laser signal to the silicon photonic integrated circuit according to the laser driving signal; the silicon photonic integrated circuit is used to transmit the laser signal to the optical scanning circuit; The scanning drive circuit is used to control the optical scanning circuit to shape the laser signal and transmit it to the object to be scanned according to the scanning drive signal, and to control the optical scanning circuit to feed back the detection light signal detected by the object to be scanned to the silicon photonic integrated circuit; The silicon photonic integrated circuit is further configured to provide a detection electrical signal to the main control circuit according to the detection laser signal; The main control circuit is further configured to determine an optical scanning result based on the detection electrical signal.

2. The laser radar system according to claim 1, characterized in that The laser driving circuit is specifically used to control the frequency of the laser signal emitted by the laser generating circuit according to the scanning driving signal; The silicon photonic integrated circuit is used to perform optical splitting processing on the laser signal and transmit the processed laser signal to the optical scanning circuit; The silicon photonic integrated circuit is further configured to receive the detection light signal fed back by the optical scanning circuit and convert the detection light signal into a detection electrical signal.

3. The laser radar system according to claim 2, characterized in that The silicon photonic integrated circuit includes a beam splitting unit and a photodetector; The beam splitting unit is used to split the laser signal into a detection laser and a local oscillation laser, and transmit the detection laser to the optical scanning circuit, and transmit the local oscillation laser to the photodetector; The photodetector is used to receive the detection light signal fed back by the optical scanning circuit, and generate a detection electrical signal according to the detection light signal and the local oscillation laser.

4. The laser radar system according to claim 3, characterized in that The laser radar system further includes an optical detection circuit; the optical detection circuit and the silicon photonic integrated circuit are arranged in the same circuit board; The optical detection circuit is used to amplify the detection electrical signal and output the amplified detection electrical signal to the main control circuit.

5. The laser radar system according to claim 1, wherein: The optical scanning circuit includes a lens assembly and a rotating mechanism; the rotating mechanism is connected to the lens assembly; The scanning drive circuit is specifically used to control the rotating mechanism to drive the lens assembly to rotate according to the scanning drive signal, so as to adjust the optical parameters of the laser signal and the detection light signal passing through the lens assembly.

6. The laser radar system according to claim 1, characterized in that The main control circuit includes a main control module and a modulation module; The main control module is used to provide a modulation control signal to the modulation module; The modulation module is used to provide the laser driving signal to the laser driving circuit according to the modulation control signal.

7. The laser radar system according to claim 6, characterized in that The main control circuit also includes a chip control module; The chip control module is used to obtain the working condition information of the silicon photonic integrated circuit in real time, and feed back the current working condition information of the silicon photonic integrated circuit to the main control module; The main control module is further configured to control the provision of the modulation control signal to the modulation module and the provision of the chip control signal to the chip control module according to current operating condition information of the silicon photonic integrated circuit; The chip control module is further configured to adjust the operating state of the silicon photonic integrated circuit according to the chip control signal.

8. The laser radar system according to claim 6, characterized in that The main control circuit also includes an analog-to-digital conversion module and a storage module; The analog-to-digital conversion module is used to convert the detection electrical signal into a digital detection signal; The main control module is specifically configured to determine the optical scanning result according to the digital detection signal, and control the digital detection signal and the optical scanning result to be stored in the storage module.

9. The laser radar system according to claim 8, characterized in that The main control circuit also includes a communication module; The communication module is connected between the main control module and the external device; the communication module is used to control the external device to exchange information with the main control module.

10. The laser radar system according to claim 6, characterized in that Also includes: Power module; The power supply module is used to respectively supply power to the silicon photonic integrated circuit, the laser generating circuit, the optical scanning circuit, the scanning driving circuit, the laser driving circuit and the main control circuit; Wherein, the power module and the main control circuit are arranged in the same circuit board.

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