LiDAR system, subsystems thereof, and methods of operation thereof

Abstract

This application relates to a LiDAR system, its subsystems, and a method of operation thereof. The light source circuit of the LiDAR system includes four capacitors, four laser diodes, two charging circuits, four switches, and two drivers. A first driver is configured to discharge a first capacitor via a first laser diode by engaging a first switch, and to discharge a third capacitor via a third laser diode by engaging a third switch. A second driver is configured to discharge a second capacitor via a second laser diode by engaging a second switch, and to discharge a fourth capacitor via a fourth laser diode by engaging a fourth switch. The disclosed light source circuit allows for the simultaneous charging of two or more capacitors and the sequential discharge of the capacitors via their respective laser diodes.

Description

[0001] Cross-reference

[0002] This application claims priority to Russian Patent Application No. 2024140302, filed on December 28, 2024, entitled "Optimization of the Lidar Laser Charging and Emission Circuit," the entire contents of which are incorporated herein by reference. Technical Field

[0003] This technology generally relates to systems, apparatuses, and methods that support LiDAR sensing, and more particularly to circuitry for a light source in a LiDAR system and methods for operating said circuitry. Background Technology

[0004] A light detection and ranging (LIDAR) system is a system that uses a light beam to scan space. Figure 1 The diagram illustrates a LIDAR system according to some non-limiting embodiments. The LIDAR system 100 comprises a transmitter 110 for transmitting light pulses and a receiver 120. The transmitter 110 includes a light source 112 (e.g., a laser). The light source 112 emits short light pulses 141 towards a surrounding object 140. The receiver 120 receives reflected light signals 142. By knowing the speed of light and determining the response time of the light signal from the object, the LIDAR can determine the distance to the object.

[0005] A LIDAR system can use various transmitters, scanners, and photodetectors (receivers). For example, in addition to the light source 112, the transmitter 110 also includes a scanner 111 and a driver 113. The receiver 120 includes optical components 121, a photodetector 122, and electronic devices 123. The electronic devices 123 are configured to receive and process signals from the photodetector 122. Signal processing may include amplification, attenuation, differentiation, filtering, comparison, storage, or other manipulation of electrical signals. For these purposes, the electronic devices 123 may include dedicated circuitry. The electronic devices 123 may be controlled by a control device 130, which may include a processor. The control device 130 may also control the driver 113 of the light source 112 and the scanner 111. The photodetector 122 may include a silicon photomultiplier tube (SiPM) sensor.

[0006] Several characteristics should be considered when designing a lidar system. Short laser pulses are required to measure the distance to an object with high accuracy using the time-of-flight method (i.e., when the laser emits / shoots and the receiver receives it without additional computation). Therefore, energy needs to be concentrated as much as possible in the initial stages to ensure more accurate distance measurement.

[0007] The electronic components of the light source 112 of the LIDAR transmitter 110 can impose limitations on the performance of the LIDAR system 100. To transmit the shortest possible pulse (e.g., approximately 1 ns), fast electronic components (ADC, driver, etc.) are necessary. However, the shorter the transmitted pulse, the greater the parasitic inductance, which may interfere with the proper operation of the light source 112. Some trade-offs can be made in selecting the duration of the transmitted pulse, resulting in a relatively short pulse that is acceptable for subsequent processing.

[0008] Switches can be used to generate short current pulses. These switches can be turned on and off rapidly (e.g., at approximately 400 ps). The switches can be gallium nitride (GaN) transistors, rather than silicon transistors. GaN transistors can turn on and off quickly, which is helpful for generating short laser pulses. GaN transistors are more efficient than silicon transistors and can operate at higher voltages and frequencies. This provides lower heat transfer.

[0009] Designing a LiDAR system 100, such as the light source 112 of the transmitter 110, may require the use of dedicated circuit boards and dedicated (faster) electronic components. However, faster components can be larger in size, consuming expensive "real estate" space on dedicated circuit boards. These faster components can dissipate a greater amount of heat (per unit time), and their cost may be higher, which could hinder the application of these faster components in the light source 112 of the transmitter 110.

[0010] Therefore, it is necessary to improve the light source circuit and methods of the LIDAR system transmitter.

[0011] U.S. Patent Application Publication 2024 / 0215169 A1 discloses a charging circuit for a lidar device that includes multiple energy storage devices. The lidar device also includes pulse circuitry. The charging circuit is configured to receive an instruction to trigger a first set of light emitters during a trigger cycle. The charging circuit is configured to selectively charge the first set of energy storage devices during a charging cycle. The first set of energy storage devices is a subset of the multiple energy storage devices. Summary of the Invention

[0012] One aspect of the invention is a specific circuit for supporting the charging and discharging of each capacitor via a corresponding laser diode. The disclosed circuit allows for the simultaneous charging of two or more capacitors and the sequential discharging of the capacitors via corresponding laser diodes of the capacitors.

[0013] According to embodiments of this disclosure, a LIDAR system is provided. The LIDAR system includes: a transmitting unit configured to emit light onto a surrounding object; and a receiving unit configured to detect a portion of the light reflected from the surrounding object. In some embodiments, the transmitting unit includes a subsystem. The subsystem includes a first capacitor, a second capacitor, and a first charging circuit configured to place a first charge and a second charge into the first capacitor and the second capacitor, respectively. The subsystem further includes a third capacitor, a fourth capacitor, and a second charging circuit configured to place a third charge and a fourth charge into the third capacitor and the fourth capacitor, respectively. The subsystem further includes a first light-emitting diode (LED), a second LED, a third LED, a fourth LED, a first driver configured to remove the first charge from the first capacitor via the first LED and remove the third charge from the third capacitor via the third LED; and a second driver configured to remove the second charge from the second capacitor via the second LED and remove the fourth charge from the fourth capacitor via the fourth LED. Moving the first charge, the second charge, the third charge, and the fourth charge causes the corresponding LED to emit light. In some embodiments, the subsystem is configured to operate the first charging circuit to charge the first and second capacitors, while maintaining the third and fourth capacitors without charge. The subsystem is further configured to operate the first driver to discharge the first and third capacitors, and to operate the second driver to discharge the second and fourth capacitors. In some embodiments, the subsystem is configured to operate the second charging circuit to charge the third and fourth capacitors, maintain the first and second capacitors without charge, operate the first driver to discharge the first and third capacitors, and operate the second driver to discharge the second and fourth capacitors.

[0014] In some embodiments, the LIDAR system may further include circuitry configured to coordinate the operation of the first and second drivers of the subsystem with the operation of drivers of other subsystems of the LIDAR system. In some other embodiments, the transmitting unit of the LIDAR system includes one or more other subsystems. In some embodiments of the LIDAR system, the first driver is configured to remove a first charge from a first capacitor via a first LED by engaging a first switch, and to remove a third charge from a third capacitor via a third LED by engaging a third switch; the second driver is configured to remove a second charge from a second capacitor via a second LED by engaging a second switch, and to remove a fourth charge from a fourth capacitor via a fourth LED by engaging a fourth switch. In some embodiments of the LIDAR system, the first LED is adjacent to the third LED and the second LED is adjacent to the fourth LED. In some other embodiments of the LIDAR system, each LED is a vertical-cavity surface-emitting laser diode or an edge-emitting laser diode.

[0015] According to embodiments of this disclosure, a method for operating a subsystem of a LIDAR system is provided. The subsystem includes a first capacitor, a second capacitor, a third capacitor, a fourth capacitor, a first light-emitting diode (LED), a second LED, a third LED, a fourth LED, a first driver configured to discharge the first capacitor and the third capacitor respectively through the first LED and the third LED, and a second driver configured to discharge the second capacitor and the fourth capacitor respectively through the second LED and the fourth LED. The method for operating the subsystem includes: operating a first charging circuit to place first and second charges into the first capacitor and the second capacitor respectively, while maintaining the third capacitor and the fourth capacitor without charge. The method may further include: operating the first driver to discharge the first capacitor and the third capacitor respectively through the first LED and the third LED, thereby moving the first charge through the first LED and causing only the first LED to emit light; and operating the second driver to discharge the second capacitor and the fourth capacitor respectively through the second LED and the fourth LED, thereby moving the second charge through the second LED and causing only the second LED to emit light. In some embodiments, the method may further include: maintaining the first capacitor and the second capacitor without charge; operating a second charging circuit to place third and fourth charges onto the third capacitor and the fourth capacitor, respectively; operating a first driver to discharge the first capacitor and the third capacitor through the first LED and the third LED, respectively, thereby moving the third charge through the third LED and causing only the third LED to emit light; and operating a second driver to discharge the second capacitor and the fourth capacitor through the second LED and the fourth LED, respectively, thereby moving the fourth charge through the fourth LED and causing only the fourth LED to emit light. In some embodiments, the method further includes: coordinating the operation of the first driver and the second driver with the operation of other drivers in the LiDAR system. In some other embodiments, the other drivers in the LiDAR system comprise one or more pairs of drivers.

[0016] In some embodiments of the method, the first driver removes the first charge from the first capacitor via the first LED by engaging a first switch, and the first driver also removes the third charge from the third capacitor via the third LED by engaging a third switch. The second driver removes the second charge from the second capacitor via the second LED by engaging a second switch, and the second driver also removes the fourth charge from the fourth capacitor via the fourth LED by engaging a fourth switch. In some embodiments of the method, the first LED is adjacent to the third LED and the second LED is adjacent to the fourth LED. In some other embodiments of the method, each LED is a vertical-cavity surface-emitting laser diode or an edge-emitting laser diode.

[0017] In some embodiments of the method for operating the subsystem of the LIDAR system, the first charging circuit and the second charging circuit are operated during a first time period and a second time period, respectively, the values ​​of the first charge and the second charge are defined by the first time period, and the values ​​of the third charge and the fourth charge are defined by the second time period.

[0018] According to embodiments of this disclosure, a subsystem of a LIDAR system is provided. The subsystem includes: a first capacitor, a second capacitor, and a first charging circuit configured to place a first charge and a second charge into the first capacitor and the second capacitor, respectively. The subsystem further includes: a third capacitor, a fourth capacitor, and a second charging circuit configured to place a third charge and a fourth charge into the third capacitor and the fourth capacitor, respectively. The subsystem may also include a first light-emitting diode (LED), a second LED, a third LED, a fourth LED, a first driver configured to remove the first charge from the first capacitor via the first LED and remove the third charge from the third capacitor via the third LED, and a second driver configured to remove the second charge from the second capacitor via the second LED and remove the fourth charge from the fourth capacitor via the fourth LED. Moving the first charge, the second charge, the third charge, and the fourth charge causes the corresponding LED to emit light. In some embodiments, the subsystem is configured to: operate the first charging circuit to charge the first capacitor and the second capacitor, maintain the third capacitor and the fourth capacitor without charge, operate the first driver to discharge the first capacitor and the third capacitor, operate the second driver to discharge the second capacitor and the fourth capacitor, operate the second charging circuit to charge the third capacitor and the fourth capacitor, maintain the first capacitor and the second capacitor without charge, operate the first driver to discharge the first capacitor and the third capacitor, and operate the second driver to discharge the second capacitor and the fourth capacitor.

[0019] In some embodiments of the subsystems of the LiDAR system, the LiDAR system includes circuitry configured to coordinate the operation of the first and second drivers of the subsystem with the operation of drivers of other subsystems of the LiDAR system, and / or the LiDAR system includes one or more other subsystems. In some embodiments of the subsystem, the first driver is configured to remove a first charge from a first capacitor via a first LED by engaging a first switch; the first driver is configured to remove a third charge from a third capacitor via a third LED by engaging a third switch; the second driver is configured to remove a second charge from a second capacitor via a second LED by engaging a second switch; and the second driver is configured to remove a fourth charge from a fourth capacitor via a fourth LED by engaging a fourth switch. In some embodiments of the subsystem, the first LED is adjacent to the third LED and the second LED is adjacent to the fourth LED. In some other embodiments of the subsystem, each LED is a vertical-cavity surface-emitting laser diode or an edge-emitting laser diode. In some embodiments, each switch is a gallium nitride field-effect transistor.

[0020] It should be clearly understood that the terms related to spatial orientation listed above shall be interpreted in the context of this specification, as depicted in the accompanying drawings.

[0021] The embodiments have been described above in conjunction with aspects of the invention on which the embodiments can be implemented. Those skilled in the art will understand that embodiments may be implemented in conjunction with the aspects described herein, but may also be implemented with other embodiments of those aspects. This will be understood by those skilled in the art when embodiments are mutually exclusive or otherwise incompatible. Some embodiments may be described with respect to one aspect, but may also be applicable to other aspects, as those skilled in the art will understand. Attached Figure Description

[0022] Further features and advantages of the present invention will become clear from the following detailed description, taken in conjunction with the accompanying drawings, wherein:

[0023] Figure 1 A block diagram illustrating a LIDAR system according to some non-limiting embodiments.

[0024] Figure 2 The circuitry of a light source according to some non-limiting embodiments of the disclosed technology is described.

[0025] Figure 3 The circuitry of a light source according to some non-limiting embodiments is described.

[0026] Figure 4A flowchart illustrating a method for operating a circuit of a light source according to some non-limiting embodiments.

[0027] Figure 5 The circuitry of a light source is described according to some other non-limiting embodiments.

[0028] Figure 6 A flowchart illustrating the operation method of a circuit of a light source according to some non-limiting embodiments.

[0029] Figure 7 Examples illustrating the mutual arrangement of circuit elements on the surface of a printed circuit board according to some non-limiting embodiments. Detailed Implementation

[0030] Figure 2 The circuit 200 of the light source 112 according to some non-limiting embodiments of the disclosed technology is described. A driver 201 controls a switch, which is implemented herein as a transistor 202. The transistor 202 may be, for example, a GaN transistor, which turns the laser diode 203 on and off.

[0031] The LiDAR system 100 may be a multi-channel LiDAR system and may require a light source 112 with more than one laser diode. For example, the light source 112 may have 64 laser diodes. To operate these 64 laser diodes, 64 drivers may be required—one driver for each laser diode. However, 64 drivers can occupy a significant amount of space on the circuit board and may require complex routing. Meanwhile, the circuit board of the light source 112 may have size constraints imposed by the specific embodiment of the LiDAR system 100. Applying fewer drivers in the multi-channel light source 112 can not only help maintain the desired circuit board size but also help reduce the overall cost of the circuit components, reduce the complexity of the routing on the circuit board, and provide fine-tuning (specific configuration) of the emitted light energy by simplifying the arrangement of components on the circuit board to ensure, for example, energy regulation of laser emission.

[0032] Figure 3The circuit 300 of the light source 112 according to some non-limiting embodiments is described. Circuit 300 includes two transistors (306 and 309) that connect the cathodes of laser diodes 305 and 308 to ground. The gates of transistors 306 and 309 are connected. Driver 301 operates the gates of transistors 306 and 309, and thus controls the current through laser diodes 305 and 308. The anodes of laser diodes 305 and 308 are connected to capacitors 304 and 307, respectively. The anodes of laser diodes 305 and 308 are also connected to charging anodes 302 and 303, respectively. In this embodiment, the emitter 112 can discharge laser diodes 305 and 308 sequentially, rather than simultaneously. Charging anodes 302 and 303 of the charge injection circuit are activated (receiving control signals) during corresponding time periods, voltage is fed to capacitors 304 and 307, and then the charge injection circuit deactivates charging anodes 302 and 303. The longer the charging anodes 302 and 303 are activated, the more charge accumulates on capacitors 304 and 307. For example, it is possible to fully or partially charge capacitors 304 and 307, and therefore, it is possible to adjust the power of light emission, i.e., the energy in the pulse.

[0033] Figure 4 A flowchart illustrating a method of operating circuitry 300 of light source 112 according to some non-limiting embodiments is provided. In action 401, capacitor 304 is charged. Voltage is applied to capacitor 304 through charging anode 302, and charge accumulates on capacitor 304. In action 402, driver 301 operates the gate of transistor 306 to turn it on. In action 403, transistor 306 is turned on, and a sharp current pulse passes through laser diode 305. All or part of the accumulated charge in capacitor 304 flows through laser diode 305 to ground. Therefore, laser diode 305 emits light pulses. Next, in action 404, capacitor 307 is charged. Voltage is applied to capacitor 307 through charging anode 303. In action 405, driver 301 operates transistor 309. In action 406, transistor 309 is turned on, and capacitor 307 releases its charge (or a portion of the charge) through laser diode 308. Diode laser 308 emits short pulses of light.

[0034] Figure 5The circuit 500 of a light source 112 according to some other non-limiting embodiments is described. Circuit 500 includes capacitors 511 and 521, and a charging circuit 501 configured to place a first charge and a second charge into capacitors 511 and 521, respectively. Circuit 500 further includes capacitors 531 and 541, and a charging circuit 502. Charging circuit 502 is configured to place a third charge and a fourth charge into capacitors 531 and 541, respectively. Circuit 500 includes two drivers (510 and 520) and four laser diodes: 512, 522, 532, and 542. Driver 510 is configured to remove the first charge from capacitor 511 via laser diode 512 and remove the third charge from capacitor 531 via laser diode 532. Driver 520 is configured to remove the second charge from capacitor 521 via laser diode 522 and remove the fourth charge from capacitor 541 via laser diode 542. The first, second, third and fourth charges are moved through the corresponding laser diodes (512, 522, 532 and 542) to make the corresponding laser diodes emit light.

[0035] Circuit 500 also includes four transistors: 513, 523, 533, and 543. Driver 510 is configured to remove a first charge from capacitor 511 via laser diode 512 by connecting transistor 513. Driver 510 is also configured to remove a third charge from capacitor 531 via laser diode 532 by connecting transistor 533. Driver 520 is configured to remove a second charge from capacitor 521 via laser diode 522 by connecting transistor 523. Driver 520 is also configured to remove a fourth charge from capacitor 541 via laser diode 542 by connecting transistor 543.

[0036] Figure 6 The operation of circuit 500 is explained below. In operation 601, charging circuit 501 is operated to place the first and second charges onto capacitors 511 and 521, respectively. In operation 602, capacitors 531 and 541 are kept uncharged. In operation 603, driver 510 is operated to turn on transistors 513 and 533, thereby discharging capacitors 511 and 531 through laser diodes 512 and 532, respectively. The first charge is moved through laser diode 512, causing laser diode 512 to emit light. Because only laser diode 512 has a charge on capacitor 511, only laser diode 512 emits light. Laser diode 532 does not emit light because capacitor 531 is not charged.

[0037] In action 604, the operator 520 activates transistors 523 and 543 to discharge capacitors 521 and 541 via laser diodes 522 and 542, respectively. A second charge is transferred through laser diode 522, causing it to emit light. Laser diode 542 does not emit light because capacitor 541 is not charged.

[0038] In operation 605, capacitors 511 and 521 are kept uncharged. In operation 606, charging circuit 502 is activated to place the third and fourth charges into capacitors 531 and 541, respectively. In operation 607, driver 510 is activated to turn on transistors 513 and 533, thereby discharging capacitors 511 and 531 through laser diodes 512 and 532, respectively. The third charge is moved through diode 532, causing laser diode 532 to emit light. Laser diode 512 does not emit light because capacitor 511 is uncharged.

[0039] In operation 608, the driver 520 activates transistors 523 and 543 to discharge capacitors 521 and 541 via laser diodes 522 and 542, respectively. A fourth charge is transferred through laser diode 542, causing it to emit light. Laser diode 522 does not emit light because capacitor 521 has no charge.

[0040] In some embodiments, drivers 510 and 520 coordinate their operation with the operation of other drivers in the LIDAR system 100.

[0041] Figure 7 This describes an example of the mutual arrangement of components—capacitors, transistors, laser diodes, and drivers—of a circuit 500 on the surface of a printed circuit board 700 according to some non-limiting embodiments. Figure 7 (The corresponding traces for components and charging circuits 501 and 502 are not shown.) In this example, transistor 513 is adjacent to transistor 533, and laser diode 512 is adjacent to laser diode 532. Transistor 523 is adjacent to transistor 543, and laser diode 522 is adjacent to laser diode 542.

[0042] In some embodiments, the light source 112 of the emitter 110 may contain a plurality of lasers (e.g., 64 laser diodes) and a plurality of drivers (e.g., 32 drivers). Each driver (D1, D2, ... D32) is connected to a pair of corresponding lasers (L1 and L2; L3 and L4; ...; L63 and L64) arranged sequentially in rows and columns. The light source 112 may also contain a plurality of capacitors (e.g., 64 capacitors) arranged in adjacent rows or columns. For example, two adjacent capacitors (C1 and C3; C2 and C4; ...) located on the same horizontal line may be charged simultaneously. Only lasers connected to charged capacitors can emit light. Each laser connected to a charged capacitor emits light according to a signal from the corresponding driver. In some embodiments of operation of the light source 112, only one laser can emit light at any given time. By optimizing the charging and radiating circuitry, it is possible to halve the number of drivers on the circuit board (32 instead of 64), thereby reducing the size of the circuit board, lowering the total cost of the necessary components, and simplifying the installation / wiring process.

[0043] It should be noted that in some embodiments of this technology, the processor of the control device 130 may include one or more processors and / or one or more microcontrollers configured to execute instructions and perform operations associated with the operation of the LIDAR system 100. In various non-limiting embodiments of this technology, the processor may be implemented as a single chip, a multi-chip, and / or other electronic components including one or more integrated circuits and printed circuit boards. The processor may optionally include cache memory units for temporary local storage of instructions, data, or additional computer information. For example, the processor may include one or more processors, or one or more controllers dedicated to certain processing tasks.

[0044] Furthermore, the explicit use of the terms “processor” or “controller” should not be construed as referring exclusively to hardware capable of executing software, and may implicitly include, but is not limited to, digital signal processor (DSP) hardware, network processors, application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), read-only memory (ROM), random access memory (RAM), and non-volatile storage devices for storing software.

[0045] Although the invention has been described with reference to its specific features and embodiments, it will be apparent that various modifications and combinations can be made therein without departing from the invention. Therefore, the specification and drawings are simply to be considered as a description of the invention as defined by the appended claims, and are intended to cover any and all modifications, variations, combinations, or equivalents falling within the scope of the invention.

Claims

1. A subsystem of a LiDAR system for optical detection and ranging, the subsystem comprising: A first capacitor, a second capacitor, and a first charging circuit configured to place a first charge and a second charge into the first capacitor and the second capacitor, respectively. A third capacitor, a fourth capacitor, and a second charging circuit configured to place a third charge and a fourth charge into the third capacitor and the fourth capacitor, respectively. First LED, second LED, third LED, fourth LED, A first driver, configured to remove the first charge from the first capacitor via the first LED and the third charge from the third capacitor via the third LED, and A second driver is configured to remove the second charge from the second capacitor via the second LED and the fourth charge from the fourth capacitor via the fourth LED, and to move the first charge, the second charge, the third charge, and the fourth charge via corresponding LEDs to cause the corresponding LEDs to emit light. The subsystem is configured to: Operate the first charging circuit to charge the first capacitor and the second capacitor; The third and fourth capacitors are kept free of charge. Operate the first driver to discharge the first capacitor and the third capacitor; Operate the second driver to discharge the second capacitor and the fourth capacitor; Operate the second charging circuit to charge the third capacitor and the fourth capacitor; Maintain the first capacitor and the second capacitor free of charge; Operate the first driver to discharge the first capacitor and the third capacitor; and Operate the second driver to discharge the second capacitor and the fourth capacitor.

2. The subsystem of claim 1, wherein the LiDAR system includes circuitry configured to coordinate the operation of the first and second drivers of the subsystem with the operation of drivers of other subsystems of the LiDAR system.

3. The subsystem according to claim 1, wherein the LIDAR system comprises one or more other subsystems.

4. The subsystem according to claim 1, wherein The first driver is configured to remove the first charge from the first capacitor via the first LED by engaging the first switch. The first driver is configured to remove the third charge from the third capacitor via the third LED by engaging the third switch. The second driver is configured to remove the second charge from the second capacitor via the second LED by engaging the second switch, and The second driver is configured to remove the fourth charge from the fourth capacitor via the fourth LED by engaging the fourth switch.

5. The subsystem of claim 1, wherein the first LED is adjacent to the third LED and the second LED is adjacent to the fourth LED.

6. The subsystem of claim 1, wherein each LED is a vertical cavity surface-emitting laser diode or an edge-emitting laser diode.

7. The subsystem of claim 4, wherein each switch is a gallium nitride field-effect transistor.

8. A method for operating a subsystem of a LiDAR system for optical detection and ranging. The subsystem includes: First capacitor, second capacitor, third capacitor, fourth capacitor; First LED, second LED, third LED, fourth LED; A first driver is configured to discharge the first capacitor and the third capacitor respectively via the first LED and the third LED; and A second driver is configured to discharge the second capacitor and the fourth capacitor respectively via the second LED and the fourth LED; The method includes: Operate the first charging circuit to place the first and second charges into the first capacitor and the second capacitor, respectively; The third and fourth capacitors are kept free of charge. The first driver is operated to discharge the first capacitor and the third capacitor respectively through the first LED and the third LED, thereby moving the first charge through the first LED and causing only the first LED to emit light; The second driver is operated to discharge the second capacitor and the fourth capacitor respectively through the second LED and the fourth LED, thereby moving the second charge through the second LED and causing only the second LED to emit light; Maintain the first capacitor and the second capacitor free of charge; Operate the second charging circuit to place the third and fourth charges into the third capacitor and the fourth capacitor, respectively; The first driver is operated to discharge the first capacitor and the third capacitor respectively through the first LED and the third LED, thereby moving the third charge through the third LED and causing only the third LED to emit light; and The second driver is operated to discharge the second capacitor and the fourth capacitor respectively through the second LED and the fourth LED, thereby moving the fourth charge through the fourth LED and causing only the fourth LED to emit light.

9. The method of claim 8, further comprising: Coordinate the operation of the first and second drivers with the operation of other drivers in the LiDAR system.

10. The method of claim 9, wherein the other drivers of the LiDAR system comprise one or more pairs of drivers.

11. The method of claim 8, wherein The first driver removes the first charge from the first capacitor via the first LED by engaging the first switch. The first driver removes the third charge from the third capacitor via the third LED by engaging the third switch. The second driver removes the second charge from the second capacitor via the second LED by engaging the second switch, and The second driver removes the fourth charge from the fourth capacitor via the fourth LED by engaging the fourth switch.

12. The method of claim 8, wherein the first LED is adjacent to the third LED and the second LED is adjacent to the fourth LED.

13. The method of claim 8, wherein each LED is a vertical cavity surface-emitting laser diode or an edge-emitting laser diode.

14. The method according to claim 8, The first charging circuit and the second charging circuit are operated during the first time period and the second time period, respectively. The values ​​of the first charge and the second charge are defined by the first time period, and The values ​​of the third charge and the fourth charge are defined by the second time period.

15. A LiDAR system for optical detection and ranging, comprising: A transmitting unit configured to emit light onto surrounding objects, the transmitting unit comprising a subsystem; and A receiving unit configured to detect a portion of the light reflected from the surrounding objects; The subsystem includes: A first capacitor, a second capacitor, and a first charging circuit configured to place a first charge and a second charge into the first capacitor and the second capacitor, respectively; A third capacitor, a fourth capacitor, and a second charging circuit configured to place a third charge and a fourth charge into the third capacitor and the fourth capacitor, respectively; First LED, second LED, third LED, fourth LED; A first driver is configured to remove the first charge from the first capacitor via the first LED and to remove the third charge from the third capacitor via the third LED; and A second driver is configured to remove the second charge from the second capacitor via the second LED and the fourth charge from the fourth capacitor via the fourth LED, and to move the first charge, the second charge, the third charge and the fourth charge via the corresponding LEDs to cause the corresponding LEDs to emit light; The subsystem is configured to: Operate the first charging circuit to charge the first capacitor and the second capacitor; The third and fourth capacitors are kept free of charge. Operate the first driver to discharge the first capacitor and the third capacitor; Operate the second driver to discharge the second capacitor and the fourth capacitor; Operate the second charging circuit to charge the third capacitor and the fourth capacitor; Maintain the first capacitor and the second capacitor free of charge; Operate the first driver to discharge the first capacitor and the third capacitor; and Operate the second driver to discharge the second capacitor and the fourth capacitor.

16. The LiDAR system of claim 15, further comprising circuitry configured to coordinate the operation of the first and second drivers of the subsystem with the operation of drivers of other subsystems of the LiDAR system.

17. The LiDAR system of claim 15, wherein the transmitting unit comprises one or more other subsystems.

18. The LiDAR system according to claim 15, wherein The first driver is configured to remove the first charge from the first capacitor via the first LED by engaging the first switch. The first driver is configured to remove the third charge from the third capacitor via the third LED by engaging the third switch. The second driver is configured to remove the second charge from the second capacitor via the second LED by engaging the second switch, and The second driver is configured to remove the fourth charge from the fourth capacitor via the fourth LED by engaging the fourth switch.

19. The LiDAR system of claim 15, wherein the first LED is adjacent to the third LED and the second LED is adjacent to the fourth LED.

20. The LiDAR system of claim 15, wherein each LED is a vertical-cavity surface-emitting laser diode or an edge-emitting laser diode.

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