A lidar system

Abstract

The application 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 to the laser driving circuit and provides a scanning driving signal to 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 the laser signal and emit the laser signal to a scanning object according to the scanning driving signal, and controls the optical scanning circuit to feed back a detection light signal detected by the scanning object to the silicon optical integrated circuit; the silicon optical integrated circuit provides a detection electric signal to the main control circuit; and the main control circuit determines an optical scanning result.The application improves the measurement precision and stability of the laser radar system.

Description

Technical Field

[0001] This invention relates to the field of lidar technology, and more particularly to a lidar system. Background Technology

[0002] Laser detection and ranging (LiDAR) technology measures the distance and velocity of target objects by emitting and receiving laser signals, and is widely used in fields such as autonomous driving, drone navigation, and industrial measurement. Frequency modulated continuous wave (FMCW) LiDAR systems emit laser signals whose frequency varies linearly with time, enabling simultaneous measurement of the distance and velocity of target objects, offering high precision and strong anti-interference capabilities.

[0003] Existing FMCW lidar systems typically employ a single integrated driver module. This module supplies power and modulation signals to the laser, and controls the optical scanning module for beam deflection and shaping. This integrated driver module is prone to electromagnetic noise interference, especially during high-power operation of the optical scanning module. This noise affects the laser's frequency stability and signal quality, thus reducing the measurement accuracy of the FMCW lidar system. Furthermore, the integrated driver module generates significant heat during operation, which is difficult to dissipate effectively, leading to a decrease in the stability of the FMCW lidar system. Summary of the Invention

[0004] This invention provides a lidar system that reduces noise interference and optimizes heat dissipation performance by independently driving the optical scanning circuit and the laser generation circuit, thereby improving the measurement accuracy and stability of the lidar system.

[0005] The first aspect of the present invention provides a lidar system, which includes: a silicon photonics 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 photonics integrated circuit, the scanning drive circuit, the laser drive circuit, and the main control circuit are respectively disposed on different circuit boards; the laser generating circuit and the silicon photonics integrated circuit are disposed on the same circuit board.

[0007] The main control circuit is used to provide laser driving signals to the laser driving circuit and scan driving signals 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 emit 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 emit 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 photonics integrated circuit is also used to provide a detection electrical signal to the main control circuit based on the detection optical signal;

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

[0012] Optionally, 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;

[0013] The silicon photonics integrated circuit is used to perform beam splitting on the laser signal and to transmit the processed laser signal to the optical scanning circuit.

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

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

[0016] The beam splitting unit is used to split the laser signal into a probe laser and a local oscillation laser, and to emit the probe laser to the optical scanning circuit and 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 to generate a detection electrical signal based on the detection light signal and the local oscillating laser.

[0018] Optionally, the lidar system further includes an optical detection circuit; the optical detection circuit and the silicon photonics integrated circuit are disposed on 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 rotation mechanism to rotate the lens assembly according to the scanning drive signal, so as to adjust the optical parameters of the laser signal and the detection light signal transmitted 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 modulation control signals 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 acquire the operating status information of the silicon photonic integrated circuit in real time and feed back the current operating status information of the silicon photonic integrated circuit to the main control module.

[0027] The main control module is also used to control the modulation control signal to be provided to the modulation module and the chip control signal to be provided to the chip control module according to the current operating condition information of the silicon photonic integrated circuit.

[0028] The chip control module is also used 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 converter module is used to convert the detection electrical signal into a digital detection signal;

[0031] The main control module is specifically used to determine the optical scanning result based on the digital detection signal, and to 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 interact with the main control module.

[0034] Optionally, the lidar system may also include: a power supply module;

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

[0036] The power module and the main control circuit are located on the same circuit board.

[0037] The technical solution of this invention, by incorporating a silicon photonics integrated circuit, a laser generating circuit, an optical scanning circuit, a scanning drive circuit, a laser driving circuit, and a main control circuit into a lidar system, enables the main control circuit to provide laser driving signals to the laser driving circuit and scanning drive signals to the scanning drive circuit. This allows the laser driving circuit to control the laser generating circuit to emit laser signals to the silicon photonics integrated circuit based on the laser driving signals, and further enables the silicon photonics integrated circuit to transmit the laser signals to the optical scanning circuit, thus meeting the laser source requirements of the lidar system. Simultaneously, the scanning drive circuit, based on the scanning drive signals, controls the optical scanning circuit to shape the laser signals and emit them to the object to be scanned, thereby achieving scanning of external space using the shaped laser signals. It also controls the optical scanning circuit to feed back the detection light signals detected by the object to the silicon photonics integrated circuit, so that the silicon photonics integrated circuit can also provide detection electrical signals to the main control circuit based on the detection light signals, and further enable the main control circuit to determine the optical scanning results based on the detection electrical signals. Furthermore, by placing the silicon photonics integrated circuit, scanning drive circuit, laser drive circuit, and main control circuit on separate circuit boards, physical isolation is achieved between different functional modules, avoiding mutual interference of electromagnetic signals between them. This enhances the stability and measurement accuracy of the lidar system. Simultaneously, by independently placing each functional module on different circuit boards, heat sources are dispersed, optimizing the overall heat dissipation performance of the lidar system. Finally, by placing the laser generation circuit and the silicon photonics integrated circuit on the same circuit board, stable and efficient transmission of the laser signal between the silicon photonics integrated circuit and the laser generation circuit is ensured.

[0038] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0039] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0040] Figure 1 This is a schematic diagram of the structure of a lidar system provided in an embodiment of the present invention;

[0041] Figure 2This is a schematic diagram of another lidar system provided in an embodiment of the present invention. Detailed Implementation

[0042] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0043] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0044] Figure 1 This is a schematic diagram of the structure of a lidar system provided in an embodiment of the present invention, as shown below. Figure 1 As shown, the lidar system includes: a silicon photonics integrated circuit 11, a laser generating circuit 12, an optical scanning circuit 2, a scanning drive circuit 3, a laser drive circuit 4, and a main control circuit 5; the silicon photonics integrated circuit 11, the scanning drive circuit 3, the laser drive circuit 4, and the main control circuit 5 are respectively mounted on different circuit boards; the laser generating circuit 12 and the silicon photonics integrated circuit 11 are mounted on the same circuit board; the main control circuit 5 is used to provide laser drive signals to the laser drive circuit 4 and to the scanning drive circuit 3; the laser drive circuit 4 is used to control the laser generating circuit 12 to emit laser signals to the silicon photonics integrated circuit 11 according to the laser drive signals; the silicon photonics integrated circuit 11 is used to emit laser signals to the optical scanning circuit 2; the scanning drive circuit 3 is used to control the optical scanning circuit 2 to shape the laser signals and emit them to the object to be scanned according to the scanning drive signals, and to control the optical scanning circuit 2 to feed back the detection light signals detected by the object to be scanned to the silicon photonics integrated circuit 11; the silicon photonics integrated circuit 11 is also used to provide detection electrical signals to the main control circuit 5 according to the detection light signals; the main control circuit 5 is also used to determine the optical scanning results according to the detection electrical signals.

[0045] Specifically, the main control circuit 5 can be understood as a control circuit used to control the working states of the laser drive circuit 4 and the scanning drive circuit 3 respectively. Specifically, the main control circuit 5 can generate laser drive signals and scanning drive signals according to the instructions of external devices or the feedback inside the lidar system, and can provide laser drive signals to the laser drive circuit 4 and scanning drive signals to the scanning drive circuit 3.

[0046] The laser generating circuit 12 can be specifically understood as a circuit used to generate a laser source for a lidar 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 controls 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, enable the laser to emit a laser signal with a low linewidth and a frequency that changes linearly with time. The linewidth of this laser signal can be, for example, 100 kHz. This allows the laser generating circuit 12 to transmit the laser signal to the silicon photonics integrated circuit 11, and further, through the silicon photonics integrated circuit 11, transmit the laser signal to the optical scanning circuit 2 to meet the laser source requirements of the lidar system. For example, the silicon photonics integrated circuit 11 may include a silicon photonics chip.

[0047] Specifically, the optical scanning circuit 2 can receive the laser signal emitted by the silicon photonics integrated circuit 11, shape the laser signal, and emit it to the object to be scanned, thereby achieving scanning of external space through the shaped laser signal. Furthermore, the optical scanning circuit 2 can also capture the detection light signal detected by the object to be scanned, and can reshape the detection light signal before transmitting it back to the silicon photonics integrated circuit 11 for further processing. After receiving the scanning drive signal provided by the main control circuit 5, the scanning drive circuit 3 controls the optical scanning circuit 2 to shape the laser signal and emit it to the object to be scanned. For example, the scanning drive circuit 3 controls the optical scanning circuit 2 to adjust the deflection angle, focus, and beam waist of the laser signal before emitting it to the object to be scanned, achieving omnidirectional coverage of external space. This allows the lidar system to adapt to different distances from the object to be scanned, thereby improving the detection flexibility and accuracy of the lidar system. Meanwhile, 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 photonics integrated circuit 11 so that the deflection angle, focus, and beam waist of the detection light signal can be adjusted 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 emitted light and the reflected light, and improving the transmission efficiency and signal quality of the laser signal in the lidar system.

[0048] The silicon photonics integrated circuit 11 is also used to receive the detection optical signal fed back by the optical scanning circuit 2. For example, the silicon photonics integrated circuit 11 may include a photodetector, which can convert the detection optical signal into a detection electrical signal and provide 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 and the lidar system in external space. It is understood that the frequency of the laser signal emitted by the silicon photonics integrated circuit 11 changes linearly with time. The photodetector mixes the frequency of the detection optical signal with the frequency of the laser signal to generate a difference frequency electrical signal, which can then be used to determine the spatial distance between the object to be scanned and the lidar system. Furthermore, the radial movement of the object to be scanned causes a frequency shift in the detection optical signal; therefore, by determining the Doppler frequency 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 understandable that the silicon photonics integrated circuit 11, the scanning drive circuit 3, the laser drive circuit 4, and the main control circuit 5 are respectively set on different circuit boards to achieve physical isolation between different functional modules, thereby avoiding mutual interference of electromagnetic signals between different functional modules. Specifically, the laser drive circuit 4 drives the laser generating circuit 12 in a constant current manner. By setting the laser drive circuit 4 and the scanning drive circuit 3 independently, interference from the high-frequency signals in the optical drive scanning circuit 3 to the laser drive circuit 4 is avoided, thus ensuring the accuracy of the laser signal emitted by the laser generating circuit 12 controlled by the laser drive circuit 4. By setting the scanning drive circuit 3 independently from the optical scanning circuit 2, the noise generated by the motor in the optical scanning circuit 2 when it operates at high power is avoided from affecting the high-frequency signals in the scanning drive circuit 3, ensuring the accuracy of the laser signal shaping 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, and enhancing the stability and measurement accuracy of the lidar system. Meanwhile, the scanning drive circuit 3 and the laser drive circuit 4 generate considerable heat during operation. By independently placing each functional module on different circuit boards, the heat source can be dispersed, preventing heat accumulation and thus optimizing the overall heat dissipation performance of the lidar system. Furthermore, by independently placing each functional module on different circuit boards, individual functional modules can be adjusted or optimized according to different application scenarios of the lidar system, improving the flexibility and environmental adaptability of the lidar system. In addition, by placing the laser generating circuit 12 and the silicon photonics integrated circuit 11 on the same circuit board, the relative position between the silicon photonics integrated circuit 11 and the laser generating circuit 12 is ensured to be stable. The fixed position of the silicon photonics 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 photonics integrated circuit 11 and the laser generating circuit 12, reducing laser signal transmission misalignment caused by vibration or thermal expansion.

[0050] In this embodiment, by incorporating a silicon photonics integrated circuit, a laser generating circuit, an optical scanning circuit, a scanning drive circuit, a laser driving circuit, and a main control circuit into the lidar system, the main control circuit can provide laser driving signals to the laser driving circuit and scanning drive signals to the scanning drive circuit. This allows the laser driving circuit to control the laser generating circuit to emit laser signals to the silicon photonics integrated circuit based on the laser driving signals, and further, the silicon photonics integrated circuit can transmit the laser signals to the optical scanning circuit to meet the laser source requirements of the lidar system. Simultaneously, the scanning drive circuit can control the optical scanning circuit to shape the laser signals and emit them to the object to be scanned based on the scanning drive signals, thereby achieving scanning of external space using the shaped laser signals. The scanning drive circuit also controls the optical scanning circuit to feed back the detection light signals detected by the object to be scanned to the silicon photonics integrated circuit, enabling the silicon photonics integrated circuit to provide detection electrical signals to the main control circuit based on the detection light signals, and further enabling the main control circuit to determine the optical scanning results based on the detection electrical signals. Furthermore, by placing the silicon photonics integrated circuit, scanning drive circuit, laser drive circuit, and main control circuit on separate circuit boards, physical isolation is achieved between different functional modules, avoiding mutual interference of electromagnetic signals between them. This enhances the stability and measurement accuracy of the lidar system. Simultaneously, by independently placing each functional module on different circuit boards, heat sources are dispersed, optimizing the overall heat dissipation performance of the lidar system. Finally, by placing the laser generation circuit and the silicon photonics integrated circuit on the same circuit board, stable and efficient transmission of the laser signal between the silicon photonics integrated circuit and the laser generation circuit is ensured.

[0051] Optional, Figure 2 This is a schematic diagram of another lidar system provided in an embodiment of the present invention, as shown below. 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 photonics integrated circuit 11 is used to perform beam splitting processing on the laser signal and to emit the processed laser signal to the optical scanning circuit 2; the silicon photonics integrated circuit 11 is also used to receive the detection optical signal fed back by the optical scanning circuit 2 and convert the detection optical signal into a detection electrical signal.

[0052] Specifically, the laser driving circuit 4 is used 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 driving signal. For example, the laser driving circuit 4 can provide stable power to the laser generating circuit 12 using a constant current driving method, and by adjusting the driving current or bias voltage of the laser generating circuit 12, the laser generating circuit 12 can emit a low-linewidth laser signal with a frequency that changes 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 photonics integrated circuit 11 is used to split 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 perform optical scanning using the laser signal processed by the silicon photonics integrated circuit 11. Simultaneously, the silicon photonics integrated circuit 11 is also used to receive the detection optical signal fed back from the optical scanning circuit 2 and can convert the detection optical signal into a detection electrical signal for processing by the main control circuit 5 to determine the optical scanning result. Optionally, the silicon photonics 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 a probe beam and a local oscillating beam, and send the probe beam to the optical scanning circuit 2 so that the optical scanning circuit 2 can shape the probe beam and emit it into external space, and emit the local oscillating laser to the photodetector 112; the photodetector 112 is used to receive the detection laser signal fed back from the optical scanning circuit 2 and generate a detection electrical signal based on the detection optical signal and the local oscillating beam. Furthermore, the silicon photonics integrated circuit 11 may also include an optical waveguide. Specifically, after receiving the laser signal provided by the laser generating circuit 12, the silicon photonics integrated circuit 11 first modulates the laser signal through an optical waveguide. Then, it splits the modulated laser signal into a probe light and a local oscillator light through a beam splitter unit 111. The probe light is then transmitted through the optical waveguide to the optical scanning circuit 2, allowing the optical scanning circuit 2 to shape the probe light and emit it onto the object to be scanned, thus achieving optical scanning of the object. Simultaneously, the local oscillator light is emitted to the photodetector 112 as a reference light for subsequent optical mixing by the photodetector 112. The optical waveguide also receives the detection light signal fed back from the optical scanning circuit 2 and sends it to the photodetector 112, enabling the photodetector 112 to perform optical mixing with the local oscillator light to generate a detection electrical signal. This detection electrical signal is then transmitted through the optical waveguide to the main control circuit 5, allowing the main control circuit 5 to determine the spatial distance and relative velocity between the object to be scanned and the lidar system based on the frequency and Doppler shift of the detection electrical signal, thereby improving the measurement efficiency of the lidar system. By integrating the beam splitter 111, photodetector 112, and optical waveguide into the silicon photonic integrated circuit 11, the integration of the lidar system is improved, the size of the lidar system is reduced, and thus the stability of the lidar system is improved.

[0054] Optional, continue to refer to Figure 2 The silicon photonics integrated circuit 11 also includes an optical detection circuit 13; the optical detection circuit 13 and the silicon photonics integrated circuit 11 are disposed on 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] The optical detection circuit 13 amplifies the detected electrical signal and outputs the amplified signal to the main control circuit 5. This allows the main control circuit 5 to determine the spatial distance and relative velocity between the object to be scanned and the lidar system based on the frequency and Doppler shift of the detected electrical signal. For example, the optical detection circuit 13 may include a transimpedance amplifier (TIA). Since the detected electrical signal is a weak current signal, the TIA converts it into a voltage signal and amplifies its amplitude to a level suitable for processing by the main control circuit 5. This ensures the quality of the electrical signal transmitted to the main control circuit 5 and improves the measurement efficiency and accuracy of the lidar system. Furthermore, by placing the silicon photonics integrated circuit 11 and the optical detection circuit 13 on the same circuit board, the relative position between them is ensured to be stable. This shortens the transmission path of the detected electrical signal, reduces parasitic capacitance and noise, and improves the conversion efficiency of the detected electrical signal, thereby enhancing the stability and scene adaptability of the lidar 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 transmitted through the lens assembly 21.

[0057] Specifically, the scanning drive circuit 3 is used to control the rotation mechanism 22 to rotate the lens assembly 21 according to the scanning drive signal, so as to adjust the optical parameters of the laser signal and the detection light signal transmitted through the lens assembly 21. For example, the optical parameters may include the deflection angle. By adjusting the deflection angle of the laser signal, a three-dimensional scan of the external space where the object to be scanned 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 emitted light and the reflected light, and improving the transmission efficiency and signal quality of the laser signal in the lidar system. For example, the rotation mechanism may include a mechanical frame driven by a micro-electro-mechanical system (MEMS) to adjust the deflection angle of the lens assembly 21 according to the optical scanning control signal.

[0058] Furthermore, the scanning drive circuit 3 can adjust the focal length of the lens assembly 21 according to the scanning drive signal, thereby adjusting the focal point and beam waist of the laser signal and the detection laser signal transmitted through the lens assembly 21. Specifically, the focal point of the laser signal and the detection light signal can be understood as their focused positions; the beam waist of the laser signal and the detection light signal can be understood as their minimum cross-sectional diameter. By adjusting the focal point of the laser signal, the lidar system can adapt to different detection distances; by adjusting the beam waist of the laser signal, the divergence angle of the laser signal can be optimized, enabling the lidar system to adapt to different detection scenarios. For example, a small beam waist laser signal is used for long-distance high-precision detection, while a large beam waist laser signal is used for long-distance wide-angle scanning. Simultaneously, by adjusting the focal point and beam waist of the detection light signal, it can be aligned with the focal point and beam waist of the laser signal, thereby ensuring the consistency of the emitted and reflected light and improving the transmission efficiency and signal quality of the laser signal in the lidar system. For example, lens assembly 21 may include an electrically controllable focusable lens assembly capable of adjusting the focal length and waist according to an optical scan control signal.

[0059] The scanning drive circuit 3 adjusts the focal point, beam waist, and deflection angle of the laser signal detected by the lens assembly 21, enabling the lidar system to support different detection scenarios and improving the lidar system's scene adaptability, detection efficiency, and detection accuracy.

[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 modulation control signals to the modulation module 52; the modulation module 52 is used to provide laser driving signals to the laser driving circuit 4 according to the modulation control signals.

[0061] Specifically, the main control module 51 generates a modulation control signal based on the frequency feedback of the laser signal in the lidar system. This enables the modulation module 52 to provide a laser driving signal to the laser driving circuit 4, allowing the laser driving circuit 4 to provide stable power to the laser generating circuit 12 using a constant current drive. By adjusting the driving current or bias voltage of the laser generating circuit 12, the laser generating circuit 12 can emit a laser signal with low linewidth and a frequency that changes linearly with time. Through the coordinated control of the laser driving signal provided to the laser driving circuit 4 by the main control module 51 and the modulation module 52, the stability and accuracy of the laser signal emitted by the laser generating circuit 12 driven by the laser driving circuit 4 are ensured, thereby improving the measurement accuracy and stability of the lidar 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 acquire the operating condition information of the silicon photonic integrated circuit 11 in real time and feed back the current operating 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 modulation control signals to the modulation module 52 and chip control signals to the chip control module 53 according to the current operating 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 signals.

[0063] Specifically, the chip control module 53 is used to acquire the operating condition information of the silicon photonics integrated circuit 11 in real time. For example, the chip control module 53 can acquire the current operating temperature of the silicon photonics integrated circuit 11 in real time through the temperature sensor in the silicon photonics integrated circuit 11. The chip control module 53 can also acquire the current frequency of the laser signal emitted by the silicon photonics integrated circuit 11 in real time through the photodetector 112 in the silicon photonics integrated circuit 11. The chip control module 53 can also send the real-time acquired operating condition information of the silicon photonics 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 photonics 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 it with the target frequency, it dynamically adjusts the modulation control signal provided to the modulation module 52. This allows the modulation module 52 to provide a laser driving signal to the laser driving circuit 4, 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. This ensures 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, it dynamically adjusts the chip control signal provided to the chip control module 53. This allows the chip control module 53 to dynamically adjust the current operating temperature of the silicon photonic integrated circuit 11 according to the chip control signal, ensuring that the current operating temperature of the silicon photonic integrated circuit 11 is 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 by using 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 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 converter module 54 and a storage module 55. The analog-to-digital converter 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 converter (ADC) 54 receives the amplified detection electrical signal after TIA (Translation Interaction), which is an analog voltage signal. The ADC 54 converts the detection electrical signal into a digital detection signal and transmits the converted digital detection signal to the main control module 51. Converting the detection electrical signal into a digital detection signal by the ADC 54 reduces noise interference and facilitates the main control module 51 in determining 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 ADC 54, the main control module 51 can extract the frequency information from the digital detection signal using signal processing algorithms, such as Fourier transform. This allows it to determine the spatial distance between the object to be scanned and the lidar system based on the frequency of the digital detection signal, and to determine the relative velocity between the object to be scanned and the lidar system based on the Doppler frequency shift of the digital detection signal. Furthermore, the main control module 51 can also control the storage of digital detection signals and optical scanning results in the storage module 55. Specifically, the storage module 55 can store the frequency information of the digital detection signals, the spatial distance between the object to be scanned and the LiDAR system, and the relative speed between the object to be scanned and the LiDAR system. This prevents the loss of detection data from the LiDAR system, supporting subsequent real-time or offline data analysis and troubleshooting, thereby improving the performance of the LiDAR system. For example, the storage module 55 may 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 also 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 to interact with the main control module 51.

[0068] Specifically, the communication module 56 acts as a communication bridge between the main control module 51 and the external device 6. It controls the external device 6 to interact with 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 through the communication interface. The external device 6 can be, for example, the central processing unit of an autonomous driving system or a drone navigation module, enabling the external device 6 to make real-time decisions based on the optical scanning results, such as obstacle avoidance. The communication interface of the communication module 56 can include a wired or wireless communication interface, such as Ethernet, CAN bus, Wi-Fi, or Bluetooth. Simultaneously, the communication module 56 can also receive control commands transmitted by the external device 6 through the communication interface. These control commands can be, for example, adjusting the distance, range, and angle of the optical scan. After receiving the control command, the communication module 56 can also transmit the control command to the main control module 51, so that the main control module 51 can control the scanning drive circuit 3 to provide the scanning drive signal to the optical scanning circuit 2 according to the control command. This allows the scanning drive circuit 3 to dynamically control the optical scanning circuit 2 to adjust the deflection angle, focus, and beam waist of the laser signal, so as to ensure that the distance, range, and angle of the optical scanning can meet the detection requirements of the external device 6. This enables the lidar system to adapt to different usage scenarios and improves the performance and measurement accuracy of the lidar system.

[0069] Optional, continue to refer to Figure 2 The lidar 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 located on the same circuit board.

[0070] Specifically, the power module 57 can be connected to external power supply equipment, such as a vehicle battery or industrial power supply, to receive external input power. It is understood that different functional modules have different power requirements. For example, the optical scanning circuit 2, scanning drive circuit 3, and laser drive circuit 4 require higher voltage signals, while the silicon photonics integrated circuit 11 and the main control circuit 5 require lower voltage signals. Therefore, the power module 57 can also convert the external input power into specific power supply signals required by each functional module through an internal conversion circuit, and can provide the converted power supply signals to each functional module accordingly. This achieves stable power supply for the silicon photonics integrated circuit 11, laser generation circuit 12, optical scanning circuit 2, scanning drive circuit 3, laser drive circuit 4, and main control circuit 5, ensuring the stable operation of each functional module and improving the performance and stability of the lidar system. Furthermore, the power module 57 and the main control circuit 51 are located on the same circuit board, meaning the power module 57 is also located on the same circuit board as the main control circuit 5. This reduces the number of independent circuit boards in the lidar system, simplifying the system structure and improving its overall compactness.

[0071] It should be understood that the various forms of processes shown above can be used to reorder, add, or delete steps. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution disclosed in this invention can be achieved, and this is not limited herein.

[0072] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A lidar system, characterized in that, include: Silicon photonics integrated circuit, laser generating circuit, optical scanning circuit, scanning driving circuit, laser driving circuit and main control circuit; The silicon photonics integrated circuit, the scanning drive circuit, the laser drive circuit, and the main control circuit are respectively disposed on different circuit boards; the laser generating circuit and the silicon photonics integrated circuit are disposed on the same circuit board. The main control circuit is used to provide laser driving signals to the laser driving circuit and scan driving signals 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 emit 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 emit 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 photonics integrated circuit is also used to provide a detection electrical signal to the main control circuit based on the detection laser signal; The main control circuit is also used to determine the optical scanning result based on the detected electrical signal.

2. The lidar 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 photonics integrated circuit is used to perform beam splitting on the laser signal and to transmit the processed laser signal to the optical scanning circuit. The silicon photonic integrated circuit is also used to receive the detection optical signal fed back by the optical scanning circuit and convert the detection optical signal into a detection electrical signal.

3. The lidar system according to claim 2, characterized in that, The silicon photonic integrated circuit includes a beam splitter unit and a photodetector; The beam splitting unit is used to split the laser signal into a probe laser and a local oscillation laser, and to emit the probe laser to the optical scanning circuit and 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 to generate a detection electrical signal based on the detection light signal and the local oscillating laser.

4. The lidar system according to claim 3, characterized in that, The lidar system further includes an optical detection circuit; the optical detection circuit and the silicon photonics integrated circuit are disposed on 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 lidar system according to claim 1, characterized in that, 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 rotation mechanism to rotate the lens assembly according to the scanning drive signal, so as to adjust the optical parameters of the laser signal and the detection light signal transmitted through the lens assembly.

6. The lidar 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 modulation control signals 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 lidar 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 acquire the operating status information of the silicon photonic integrated circuit in real time and feed back the current operating status information of the silicon photonic integrated circuit to the main control module; The main control module is also used to control the modulation control signal to be provided to the modulation module and the chip control signal to be provided to the chip control module according to the current operating condition information of the silicon photonic integrated circuit. The chip control module is also used to adjust the operating state of the silicon photonic integrated circuit according to the chip control signal.

8. The lidar 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 converter module is used to convert the detection electrical signal into a digital detection signal; The main control module is specifically used to determine the optical scanning result based on the digital detection signal, and to control the digital detection signal and the optical scanning result to be stored in the storage module.

9. The lidar 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 interact with the main control module.

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

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