Laser driving device and electronic product
By using the first and second trigger signals with phase difference in the laser driving device to generate narrow pulse signals, the problem of inconsistent laser generators in lidar is solved, achieving continuity and frequency consistency of laser emission, and reducing hardware costs and circuit complexity.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- NINGBO SUNNY AUTOMOTIVE OPTECH
- Filing Date
- 2024-11-01
- Publication Date
- 2026-05-08
AI Technical Summary
In lidar, the narrow pulse signals from two independent laser generators are inconsistent in pulse width and delay time, leading to problems such as laser discontinuity and inconsistent emission frequencies.
By introducing first and second laser driving components into the laser driving device, and utilizing the phase difference between the first and second trigger signals, first and second narrow pulse signals are generated to ensure the synchronization and continuity of the laser emitting components.
This improves the consistency of pulse width and delay time in the laser emission component, ensuring the continuity of laser emission and the consistency of emission frequency, while reducing hardware costs and circuit complexity.
Smart Images
Figure CN121995397A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of lidar technology, and in particular to a laser driving device and electronic product. Background Technology
[0002] A lidar system is a radar system that uses laser beams to detect the position, velocity, and other characteristics of a target. Its working principle involves emitting a laser beam towards the target and then receiving the reflected laser beam to generate radar data, thus determining the target's position and velocity. In practical applications, lidar requires the laser generator to release a large amount of energy in a short time to produce high-intensity laser pulses. If a single laser generator operates continuously, its power consumption is extremely high, potentially leading to overheating or damage. Therefore, lidar systems typically use at least two laser generators, which alternately emit light to avoid these problems.
[0003] In related technologies, the two laser generators of a lidar are usually triggered by two independent trigger signals, which trigger two driving circuits to generate narrow pulse signals for the two laser generators. However, there is no correlation between the two independent trigger signals, and the narrow pulse signals generated by the two laser generators are inconsistent in terms of pulse width and delay time, which further leads to discontinuous lasers generated by the two laser generators. Summary of the Invention
[0004] Therefore, it is necessary to provide a laser driving device and electronic product to address the aforementioned technical problems.
[0005] In a first aspect, this application provides a laser driving device, comprising: a laser driving module; the laser driving module comprising: a first laser driving component and a second laser driving component; a first input terminal of the first laser driving component is connected to a first trigger signal, a second input terminal of the first laser driving component is connected to a second trigger signal, and an output terminal of the first laser driving component is connected to a first laser emitting component, for generating a first narrow pulse signal according to the first trigger signal and the second trigger signal, and transmitting the first narrow pulse signal to the first laser emitting component to cause the first laser emitting component to generate laser light; a first input terminal of the second laser driving component is connected to the second trigger signal, a second input terminal of the second laser driving component is connected to the first trigger signal, and an output terminal of the second laser driving component is connected to a second laser emitting component, for generating a second narrow pulse signal according to the second trigger signal and the first trigger signal, and transmitting the second narrow pulse signal to the second laser emitting component to cause the second laser emitting component to generate laser light; a phase difference exists between the first trigger signal and the second trigger signal.
[0006] In one embodiment, the first laser driving component is configured to generate the first narrow pulse signal based on the rising edge of the first trigger signal and the second trigger signal; the second laser driving component is configured to generate the second narrow pulse signal based on the falling edge of the first trigger signal and the second trigger signal.
[0007] In one embodiment, the first laser driving component is configured to output the first narrow pulse signal when the first trigger signal is high and the second trigger signal is low; the second laser driving component is configured to output the second narrow pulse signal when the second trigger signal is high and the first trigger signal is low.
[0008] In one embodiment, the laser driving module further includes a first high-speed switch and a second high-speed switch; the output terminal of the first laser driving component is connected to the first laser emitting component through the first high-speed switch; the output terminal of the second laser driving component is connected to the second laser emitting component through the second high-speed switch.
[0009] In one embodiment, both the first laser driving component and the second laser driving component are narrow pulse generators; the first input terminal of the first laser driving component is the positive input terminal of the narrow pulse generator, and the second input terminal of the first laser driving component is the negative input terminal of the narrow pulse generator; the first input terminal of the second laser driving component is the positive input terminal of the narrow pulse generator, and the second input terminal of the second laser driving component is the negative input terminal of the narrow pulse generator.
[0010] In one embodiment, the laser driving device further includes a trigger signal generating component; the trigger signal generating component is connected to a first input terminal of the first laser driving component, a second input terminal of the first laser driving component, a first input terminal of the second laser driving component, and a second input terminal of the second laser driving component, respectively, for generating the first trigger signal and the second trigger signal, and outputting the first trigger signal to the first input terminal of the first laser driving component and the second input terminal of the second laser driving component, respectively, and outputting the second trigger signal to the second input terminal of the first laser driving component and the first input terminal of the second laser driving component, respectively.
[0011] In one embodiment, the trigger signal generation component includes a trigger signal element and a phase shift element; the trigger signal element is connected to a first input terminal of the first laser driving component, a second input terminal of the second laser driving component, and the phase shift element, respectively, for generating the first trigger signal and outputting the first trigger signal to the first input terminal of the first laser driving component, the second input terminal of the second laser driving component, and the phase shift element, respectively; the phase shift element is connected to the second input terminal of the first laser driving component and the first input terminal of the second laser driving component, respectively, for receiving the first trigger signal, performing phase shift processing on the first trigger signal to generate the second trigger signal, and outputting the second trigger signal to the second input terminal of the first laser driving component and the first input terminal of the second laser driving component.
[0012] In one embodiment, the phase-shifting element includes: a first delay circuit, a second delay circuit, and a shaping circuit; the first delay circuit is connected to the first input terminals of the trigger signal element and the shaping circuit, respectively, for receiving the first trigger signal and performing delay processing on the first trigger signal to obtain a first delayed signal; the second delay circuit is connected to the second input terminals of the trigger signal element and the shaping circuit, respectively, for receiving the first trigger signal and performing delay processing on the first trigger signal to obtain a second delayed signal; the output terminal of the shaping circuit is connected to the second input terminal of the first laser driving component and the first input terminal of the second laser driving component, respectively, for performing shaping processing on the first delayed signal and the second delayed signal to obtain the second trigger signal.
[0013] In one embodiment, the shaping circuit is an AND gate shaping circuit, used to output a high level of the second trigger signal if both the rising edge voltage of the first delayed signal and the rising edge voltage of the second delayed signal are greater than the rising edge threshold of the AND gate; and to output a low level of the second trigger signal if either the falling edge voltage of the first delayed signal or the falling edge voltage of the second delayed signal is less than the falling edge threshold of the AND gate.
[0014] In one embodiment, both the first delay circuit and the second delay circuit are RC delay circuits.
[0015] In one embodiment, the trigger signal generation component includes a SPAD chip.
[0016] In one embodiment, the laser driving device includes: a plurality of laser driving modules; the trigger signal generation component includes: a programmable logic chip having a plurality of phase shift modules; the plurality of phase shift modules of the programmable logic chip respectively generate a plurality of third trigger signals with different phases; each laser driving module is connected to any two of the phase shift modules respectively.
[0017] Secondly, this application also provides an electronic product, which includes a laser driving device and a laser emitting component as described in any of the embodiments of the first aspect above; the laser driving device is connected to the laser emitting component and is used to drive the laser emitting component to generate laser light.
[0018] The aforementioned laser driving device and electronic product, wherein the laser driving device includes a laser driving module, and the laser driving module includes a first laser driving component and a second laser driving component. The first laser driving component has a first input terminal connected to a first trigger signal, a second input terminal connected to a second trigger signal, and an output terminal connected to a first laser emitting component. It is used to generate a first narrow pulse signal based on the first and second trigger signals, and transmit the first narrow pulse signal to the first laser emitting component to generate laser light. The second laser driving component has a first input terminal connected to the second trigger signal, a second input terminal connected to the first trigger signal, and an output terminal connected to a second laser emitting component. It is used to generate a second narrow pulse signal based on the second and first trigger signals, and transmit the second narrow pulse signal to the second laser emitting component to generate laser light. The first and second trigger signals are in different phases. Both the first laser driving component and the second laser driving component are triggered by the first trigger signal and the second trigger signal, that is, the trigger signals of the two laser driving components are the same. Based on the different phases of the first trigger signal and the second trigger signal, a first narrow pulse signal and a second narrow pulse signal are generated, which improves the consistency of the two narrow pulse signals in terms of pulse width and delay time, thereby making the laser generated by the two laser emitting components more continuous. Attached Figure Description
[0019] Figure 1 This is a schematic diagram of a laser-driven structure in a related technology;
[0020] Figure 2 This is a schematic diagram of the structure of the laser driving device in one embodiment;
[0021] Figure 3 This is a timing diagram of the generation of a narrow pulse signal in one embodiment;
[0022] Figure 4This is a schematic diagram of the laser driving device in another embodiment;
[0023] Figure 5 This is a schematic diagram of the laser driving device in another embodiment;
[0024] Figure 6 This is a schematic diagram of the laser driving device in another embodiment;
[0025] Figure 7 This is a schematic diagram of the laser driving device in another embodiment;
[0026] Figure 8 This is a schematic diagram of the laser driving device in another embodiment;
[0027] Figure 9 This is a timing diagram of the delayed signal in one embodiment;
[0028] Figure 10 This is a schematic diagram of the laser driving device in another embodiment;
[0029] Figure 11 This is a schematic diagram of the structure of a laser driving device in a specific embodiment;
[0030] Figure 12 This is a timing diagram for generating a narrow pulse signal in a specific embodiment.
[0031] Explanation of reference numerals in the attached figures: 100, laser driving module; 110, first laser driving component; 120, second laser driving component; 130, first laser emitting component; 140, second laser emitting component; 150, first high-speed switch; 160, second high-speed switch; 200, trigger signal generation component; 210, trigger signal element; 220, phase shift element; 221, first delay circuit; 222, second delay circuit; 223, shaping circuit. Detailed Implementation
[0032] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.
[0033] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.
[0034] It is understood that the terms "first," "second," etc., used herein may be used to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish one element from another. For example, without departing from the scope of this application, a first resistor may be referred to as a second resistor, and similarly, a second resistor may be referred to as a first resistor. Both the first resistor and the second resistor are resistors, but they are not the same resistor.
[0035] When a lidar system is in use, its laser emitting module generates a laser beam. This beam strikes the target object and is reflected back to the lidar's laser receiving module, generating radar data. During the scanning process, the lidar's scanning module adjusts the laser beam's position at a preset angle, continuously adjusting the position to ensure the scanning range covers the entire space. For example, a lidar system with two laser emitting modules... Figure 1 As shown, in the related technology, two laser drivers respectively drive two laser emitting modules. Laser driver 1 is connected to trigger signal 1 and control signal 1. Laser driver 1 generates a narrow pulse signal 1 through trigger signal 1 and control signal 1, and drives laser emitting module 1 through the narrow pulse signal 1. Laser driver 2 is connected to trigger signal 2 and control signal 2. Laser driver 2 generates a narrow pulse signal 2 through trigger signal 2 and control signal 2, and drives laser emitting module 2 through the narrow pulse signal 2. There is no correlation between trigger signal 1, control signal 1, trigger signal 2, and control signal 2. Therefore, there will be inconsistencies in pulse width and delay time between the narrow pulse signal 1 generated by trigger signal 1 and control signal 1 and the narrow pulse signal 2 generated by trigger signal 2 and control signal 2. This will result in discontinuous laser output from laser emitting module 1 and laser emitting module 2, inconsistent emission frequencies between laser emitting module 1 and laser emitting module 2, or unstable emission intervals between laser emitting module 1 and laser emitting module 2 when they emit light alternately.
[0036] This application provides a laser driving device, such as... Figure 2 As shown, the laser driving device includes a laser driving module 100; the laser driving module 100 includes a first laser driving component 110 and a second laser driving component 120. The laser driving device may include at least one laser driving module 100; this embodiment uses one laser driving module 100 as an example for illustration.
[0037] The first input terminal of the first laser driving component 110 is connected to a first trigger signal, the second input terminal of the first laser driving component 110 is connected to a second trigger signal, and the output terminal of the first laser driving component 110 is connected to a first laser emitting component 130. This is used to generate a first narrow pulse signal based on the first and second trigger signals, and to transmit the first narrow pulse signal to the first laser emitting component 130, so that the first laser emitting component 130 generates laser light. The first input terminal of the second laser driving component 120 is connected to the second trigger signal, the second input terminal of the second laser driving component 120 is connected to the first trigger signal, and the output terminal of the second laser driving component 120 is connected to a second laser emitting component 140. This is used to generate a second narrow pulse signal based on the second and first trigger signals, and to transmit the second narrow pulse signal to the second laser emitting component 140, so that the second laser emitting component 140 generates laser light.
[0038] The first laser emitting component 130 and the second laser emitting component 140 can be lasers, such as solid-state lasers, semiconductor lasers, etc. This embodiment does not specifically limit the type of the first laser emitting component 130 and the second laser emitting component 140, as long as they can generate laser light by being driven by a first narrow pulse signal or a second narrow pulse signal. The first laser driving component 110 and the second laser driving component 120 can be narrow pulse generators, or any element capable of driving a laser to generate a laser beam. The first trigger signal and the second trigger signal can be generated by the timing control unit of the SPAD sensor, or by any circuit or chip capable of generating PWM signals. This embodiment does not specifically limit this, as long as there is a phase difference between the first trigger signal and the second trigger signal, that is, the phases of the first trigger signal and the second trigger signal are different.
[0039] The first laser driving component 110 and the second laser driving component 120 have identical structures. For the first laser driving component 110, a first trigger signal is input to its first input terminal, and a second trigger signal is input to its second input terminal. Similarly, for the second laser driving component 120, a first trigger signal is input to its second input terminal, and a second trigger signal is input to its first input terminal. The first laser driving component 110 generates a first narrow pulse signal based on the first phase characteristics of the first and second trigger signals. The second laser driving component 120 generates a second narrow pulse signal based on the second trigger signal and the second phase characteristics of the first trigger signal. The first narrow pulse signal then drives the first laser emitting component 130 to generate laser light, and the second narrow pulse signal then drives the second laser emitting component 140 to generate laser light.
[0040] In the aforementioned laser driving device, both the first laser driving component 110 and the second laser driving component 120 are triggered by a first trigger signal and a second trigger signal, meaning that the trigger signals for the two laser driving components are the same. Based on the different phases of the first trigger signal and the second trigger signal, a first narrow pulse signal and a second narrow pulse signal are generated, which improves the consistency of the two narrow pulse signals in terms of pulse width and delay time. This makes the lasers generated by the two laser emitting components more continuous, makes the emission frequencies of the two laser emitting components consistent, and makes the emission interval of the first laser emitting component 130 and the second laser emitting component 140 more stable when emitting light alternately.
[0041] In one embodiment, the first laser driving component 110 is used to generate a first narrow pulse signal based on the rising edges of the first trigger signal and the second trigger signal; the second laser driving component 120 is used to generate a second narrow pulse signal based on the falling edges of the first trigger signal and the second trigger signal.
[0042] like Figure 3 As shown, there is a phase difference between the first trigger signal and the second trigger signal. This phase difference is related to the pulse width of the narrow pulse signal generated by the laser driving component. The first phase characteristic, also known as the rising edge characteristic, of the first trigger signal and the second trigger signal is that within one cycle corresponding to the time of the first and second trigger signals, the first laser driving component 110 outputs a high level of the first narrow pulse signal between the rising edge of the first trigger signal and the rising edge of the second trigger signal, and outputs a low level of the first narrow pulse signal at other times. The second phase characteristic, also known as the falling edge characteristic, of the first trigger signal and the second trigger signal is that within one cycle corresponding to the time of the first and second trigger signals, the second laser driving component 120 outputs a high level of the second narrow pulse signal between the falling edge of the first trigger signal and the falling edge of the second trigger signal, and outputs a low level of the second narrow pulse signal at other times.
[0043] In this embodiment, the first laser driving component 110 samples the rising edges of the first and second trigger signals to generate a first narrow pulse signal; the second laser driving component 120 samples the falling edges of the first and second trigger signals to generate a second narrow pulse signal. Compared with related technologies, the high-level output frequency of the narrow pulse signal is doubled, further improving the light extraction efficiency of the laser emitting component.
[0044] In one embodiment, such as Figure 3As shown, the first laser driving component 110 is used to output a first narrow pulse signal when the first trigger signal is high and the second trigger signal is low; the second laser driving component 120 is used to output a second narrow pulse signal when the second trigger signal is high and the first trigger signal is low.
[0045] After receiving the first trigger signal and the second trigger signal, the first laser driving component 110 outputs a high level of the first narrow pulse signal when the first trigger signal is a high level signal and the second trigger signal is a low level signal; outputs a low level of the first narrow pulse signal when the first trigger signal is a high level signal and the second trigger signal is a high level signal; outputs a low level of the first narrow pulse signal when the first trigger signal is a low level signal and the second trigger signal is a low level signal; and outputs a low level of the first narrow pulse signal when the first trigger signal is a low level signal and the second trigger signal is a high level signal.
[0046] After receiving the first trigger signal and the second trigger signal, the second laser driving component 120 outputs a high level of the second narrow pulse signal when the second trigger signal is high and the first trigger signal is low; outputs a low level of the second narrow pulse signal when the second trigger signal is high and the first trigger signal is high; outputs a low level of the second narrow pulse signal when the second trigger signal is low and the first trigger signal is low; and outputs a low level of the second narrow pulse signal when the second trigger signal is low and the first trigger signal is high.
[0047] This embodiment can accurately determine the high level of the narrow pulse signal by changing the level of the first trigger signal and the second trigger signal, thereby further accurately determining the time when the laser generates laser light.
[0048] In one embodiment, such as Figure 4 As shown, the laser driving module 100 also includes a first high-speed switch 150 and a second high-speed switch 160; the output terminal of the first laser driving component 110 is connected to the first laser emitting component 130 through the first high-speed switch 150; the output terminal of the second laser driving component 120 is connected to the second laser emitting component 140 through the second high-speed switch 160.
[0049] A first high-speed switch 150 is located between the output terminal of the first laser driving component 110 and the first laser emitting component 130, and is used to control the transmission of a first narrow pulse signal to the first laser emitting component 130. A second high-speed switch 160 is located between the output terminal of the second laser driving component 120 and the second laser emitting component 140, and is used to control the transmission of a second narrow pulse signal to the second laser emitting component 140. The high-speed switches have a high-speed switching function, ensuring that when a high level of the narrow pulse signal arrives, the high-speed switch quickly turns on; when a low level of the narrow pulse signal arrives, the high-speed switch quickly turns off. In the on state, the high-speed switch has low on-resistance, which reduces signal loss; in the off state, the high-speed switch has high blocking capability, which prevents signal leakage.
[0050] This embodiment, by setting a first high-speed switch 150 and a second high-speed switch 160, can ensure that the first narrow pulse signal and the second narrow pulse signal are accurately transmitted to the first laser emitting component 130 and the second laser emitting component 140, thereby further ensuring the accuracy and consistency of the laser emitted by the laser emitting component.
[0051] In one embodiment, the first high-speed switch 150 includes any one of a gallium nitride switch, a silicon carbide switch, and a MOSFET; the second high-speed switch 160 includes any one of a gallium nitride switch, a silicon carbide switch, and a MOSFET.
[0052] In one embodiment, such as Figure 5 As shown, both the first laser driving component 110 and the second laser driving component 120 are narrow pulse generators; the first input terminal of the first laser driving component 110 is the positive input terminal of the narrow pulse generator, and the second input terminal of the first laser driving component 110 is the negative input terminal of the narrow pulse generator; the first input terminal of the second laser driving component 120 is the positive input terminal of the narrow pulse generator, and the second input terminal of the second laser driving component 120 is the negative input terminal of the narrow pulse generator.
[0053] A narrow pulse generator is a dedicated chip for driving gallium nitride switches or MOSFETs. It includes a positive input terminal, a negative input terminal, and an output terminal. Its truth table is as follows:
[0054] IN- IN+ OUTH OUTL L L Open L L H H Open H L Open L H H Open L
[0055] In this circuit, IN+ is the positive input terminal, IN- is the negative input terminal, and OTH and OUTL are the output terminals. L represents a low level, H represents a high level, and Open represents output cutoff. When both the positive and negative input terminals of the narrow pulse generator are low, the output is low; when both the positive and negative input terminals are high, the output is high; when both the positive and negative input terminals are high, the output is low; and when both the positive and negative input terminals are high, the output is low.
[0056] When the first laser driving component 110 is a narrow pulse generator, the positive input terminal is connected to the first trigger signal, the negative input terminal is connected to the second trigger signal, and the output terminal outputs the first narrow pulse signal.
[0057] When the second laser driving component 120 is a narrow pulse generator, the positive input terminal is connected to the second trigger signal, the negative input terminal is connected to the first trigger signal, and the output terminal outputs the second narrow pulse signal.
[0058] The narrow pulse generator can precisely control the generation of narrow pulse signals based on the trigger signals input to its positive and negative input terminals, thereby further ensuring the accuracy and consistency of laser emission from the laser emitting component.
[0059] In one embodiment, such as Figure 6 As shown, the laser driving device also includes a trigger signal generation component 200; the trigger signal generation component 200 is connected to the first input terminal of the first laser driving component 110, the second input terminal of the first laser driving component 110, the first input terminal of the second laser driving component 120, and the second input terminal of the second laser driving component 120, respectively, for generating a first trigger signal and a second trigger signal, and outputting the first trigger signal to the first input terminal of the first laser driving component 110 and the second input terminal of the second laser driving component 120, respectively, and outputting the second trigger signal to the second input terminal of the first laser driving component 110 and the first input terminal of the second laser driving component 120, respectively.
[0060] The trigger signal generation component 200 can be a SPAD sensor (Single Photon Avalanche Diode), or a timing control unit of a SPAD chip, or a circuit or chip such as an MCU or FPGA capable of generating PWM signals. The trigger signal generation component 200 generates a first trigger signal and a second trigger signal. The phase difference between the first and second trigger signals is related to the pulse width of the narrow pulse signal generated by the laser driving component. The specific phase difference setting can be customized according to the actual usage requirements of the lidar; this embodiment does not impose specific limitations. After generating the first and second trigger signals, the trigger signal generation component 200 sends the first and second trigger signals to the first laser driving component 110 and the second laser driving component 120, respectively.
[0061] In this embodiment, the first trigger signal and the second trigger signal are uniformly generated by the trigger signal generation component 200, and the first trigger signal and the second trigger signal are transmitted to the laser driving component. This simplifies the circuit design, reduces hardware costs and complexity, reduces the overall circuit size and power consumption, and further ensures the consistency of the generated narrow pulse signal in terms of pulse width and delay time.
[0062] In one embodiment, such as Figure 7 As shown, the trigger signal generation component 200 includes a trigger signal element 210 and a phase shift element 220. The trigger signal element 210 is connected to the first input terminal of the first laser driving component 110, the second input terminal of the second laser driving component 120, and the phase shift element 220, respectively, for generating a first trigger signal and outputting the first trigger signal to the first input terminal of the first laser driving component 110, the second input terminal of the second laser driving component 120, and the phase shift element 220, respectively. The phase shift element 220 is connected to the second input terminal of the first laser driving component 110 and the first input terminal of the second laser driving component 120, respectively, for receiving the first trigger signal, performing phase shift processing on the first trigger signal to generate a second trigger signal, and outputting the second trigger signal to the second input terminal of the first laser driving component 110 and the first input terminal of the second laser driving component 120.
[0063] The trigger signal element 210 can be a SPAD sensor, i.e., the timing control unit of a SPAD chip, or a circuit or chip such as an MCU or FPGA that can generate PWM signals, used to generate the first trigger signal. The phase shift element 220 can be a delay shaping circuit, an FPGA, a CPLD, or a high-precision buffer, or any element capable of phase shifting the trigger signal. This embodiment does not specifically limit the types of the trigger signal element 210 and the phase shift element 220. Specifically, when performing phase shifting, the FPGA and CPLD use the IOdelay function of their internal logic gates to phase shift the input signal and generate a phase-shifted signal corresponding to the input signal. The high-precision buffer is a dedicated logic chip that implements phase shifting through logic gate circuits, enabling the generation of a phase-shifted signal corresponding to the input signal by setting an output delay. Specifically, the trigger signal element 210 generates a first trigger signal and transmits the first trigger signal to the first laser driving component 110, the second laser driving component 120 and the phase shift element 220 respectively. When the phase shift element 220 receives the first trigger signal, it performs phase shift processing on the first trigger signal through its own phase shift function to generate a second trigger signal and transmits the second trigger signal to the first laser driving component 110 and the second laser driving component 120 respectively.
[0064] In one embodiment, such as Figure 8 As shown, the phase shift element 220 includes: a first delay circuit 221, a second delay circuit 222, and a shaping circuit 223; the first delay circuit 221 is connected to the first input terminals of the trigger signal element 210 and the shaping circuit 223 respectively, and is used to receive the first trigger signal and perform delay processing on the first trigger signal to obtain a first delayed signal; the second delay circuit 222 is connected to the second input terminals of the trigger signal element 210 and the shaping circuit 223 respectively, and is used to receive the first trigger signal and perform delay processing on the first trigger signal to obtain a second delayed signal; the output terminal of the shaping circuit 223 is connected to the second input terminal of the first laser driving component 110 and the first input terminal of the second laser driving component 120 respectively, and is used to perform shaping processing on the first delayed signal and the second delayed signal to obtain a second trigger signal.
[0065] The first delay circuit 221 and the second delay circuit 222 can be RC delay circuits, such as... Figure 9As shown, after receiving the first trigger signal, the first delay circuit 221 delays the first trigger signal to generate a first delayed signal; the second delay circuit 222 delays the first trigger signal to generate a second delayed signal. The first delayed signal has a first delay time relative to the first trigger signal, and the second delayed signal has a second delay time relative to the second trigger signal. The first delay time is shorter than the second delay time, and the difference between the first and second delay times is related to the pulse width of the narrow pulse signal generated by the laser driving component. Therefore, the first and second delay times need to be set according to the actual usage requirements of the lidar; this embodiment does not impose specific limitations. Adjusting the delay time of the first delay circuit 221 or the second delay circuit 222 can be achieved by adjusting the capacitance in the RC delay circuit.
[0066] The shaping circuit 223 can be an AND gate shaping circuit, which includes a positive input terminal and a negative input terminal. The first delay circuit 221 transmits the first delayed signal to the positive terminal of the AND gate shaping circuit, and the second delay circuit 222 transmits the second delayed signal to the negative terminal of the AND gate shaping circuit. When the AND gate shaping circuit shapes the first trigger signal and the second trigger signal, if both the rising edge voltage of the first delay signal and the rising edge voltage of the second delay signal are greater than the AND gate rising edge threshold, then the second trigger signal is output at a high level. If either the falling edge voltage of the first delay signal or the falling edge voltage of the second delay signal is less than the AND gate falling edge threshold, then the second trigger signal is output at a low level. After generating the second trigger signal, the second trigger signal is transmitted to the first laser driving component 110 and the second laser driving component 120, respectively.
[0067] In one embodiment, such as Figure 10 As shown, the laser driving device includes: multiple laser driving modules; the trigger signal generation component includes: a programmable logic chip with multiple phase shift modules; the multiple phase shift modules of the programmable logic chip generate multiple third trigger signals with different phases; each laser driving module is connected to any two phase shift modules.
[0068] In this embodiment, the laser driving device includes multiple laser driving modules, and each laser driving module includes two laser driving components. The corresponding trigger signal generation module can be a programmable logic chip, such as an FPGA chip or a CPLD chip. This programmable logic chip internally includes multiple phase shift modules, with each pair of phase shift modules corresponding to one laser driving module, i.e., two laser driving components. For example, the laser driving device includes two laser driving modules, and the programmable logic chip contains four phase shift modules. The first phase shift module is connected to the positive input terminal of the first laser driving component and the negative input terminal of the second laser driving component; the second phase shift module is connected to the negative input terminal of the first laser driving component and the positive input terminal of the second laser driving component; the third phase shift module is connected to the positive input terminal of the third laser driving component and the negative input terminal of the fourth laser driving component; and the fourth phase shift module is connected to the negative input terminal of the third laser driving component and the positive input terminal of the fourth laser driving component. Each phase shift module can generate a third trigger signal. The phase difference between the third trigger signal generated by the first phase shift module and the third trigger signal generated by the second phase shift module is related to the pulse width of the narrow pulse signals corresponding to the first and second laser emitting components. Similarly, the phase difference between the third trigger signal generated by the third phase shift module and the third trigger signal generated by the fourth phase shift module is also related to the pulse width of the narrow pulse signals corresponding to the third and fourth laser emitting components. The first phase shift module outputs the first third trigger signal, and the phase difference between the third trigger signal output by each subsequent phase shift module and the first third trigger signal increases sequentially. The first third trigger signal output by the first phase shift module can be considered a reference signal with a phase shift of 0. For example, the laser driving device can also include two laser driving modules, with three phase shift modules within the programmable logic chip. The programmable logic chip can generate the first third trigger signal, which is then input to the three phase shift modules, with each phase shift module outputting its corresponding third trigger signal. The first third trigger signal generated by the programmable logic chip is transmitted to the positive input terminal of the first laser driver component and the negative input terminal of the second laser driver component; the third trigger signal generated by the first phase shift module is transmitted to the negative input terminal of the first laser driver component and the positive input terminal of the second laser driver component; the third trigger signal generated by the second phase shift module is transmitted to the positive input terminal of the third laser driver component and the negative input terminal of the fourth laser driver component; the third trigger signal generated by the third phase shift module is transmitted to the negative input terminal of the third laser driver component and the positive input terminal of the fourth laser driver component. When the laser driving device has an odd number of laser driver components, the last laser driver component is equipped with two separate phase shift modules, which are connected to the positive and negative input terminals of the laser driver component, respectively.
[0069] In a specific embodiment, due to limitations such as power consumption and heat dissipation, the laser emitting module of a lidar typically requires multiple channels, meaning multiple laser emitting modules take turns emitting light. This necessitates generating two narrow pulse signals to alternately excite and drive the laser emitting modules. In conventional lidar solutions, the narrow pulse signal is usually generated by an AND gate and RC delay combination circuit. If N narrow pulse signals are needed, N independent AND gate and RC delay combination circuits are required. Because the parameters of analog devices such as RC circuits exhibit individual discrete differences, a serious problem of poor consistency of the narrow pulse signals between channels arises. Figure 11 as well as Figure 12 As shown, this embodiment provides a laser driving device. The original trigger signal, also known as the first trigger signal, is generated by the SPAD sensor transmission timing control unit. The original trigger signal is delayed by an RC circuit to generate delayed signal 1, which is transmitted to the positive terminal of the AND gate. The original trigger signal is delayed by another RC circuit to generate delayed signal 2, which is transmitted to the negative terminal of the AND gate. After receiving delayed signal 1 and delayed signal 2, the AND gate performs logical judgment and edge acceleration to generate a phase-shifted signal, which is the second trigger signal. When both delayed signal 1 and delayed signal 2 exceed the rising edge threshold of the AND gate, the AND gate outputs a high level; when at least one of delayed signal 1 and delayed signal 2 is below the falling edge threshold of the AND gate, the AND gate outputs a low level. The original trigger signal is input to the positive input terminal (IN+) of the narrow pulse generator 1 and the negative input terminal (IN-) of the narrow pulse generator 2; the phase-shifted signal is input to the negative input terminal (IN-) of the narrow pulse generator 1 and the positive input terminal (IN+) of the narrow pulse generator 2. Narrow pulse generator 1 outputs a narrow pulse signal 1 to high-speed switch 1, which drives laser 1. Narrow pulse generator 2 outputs a narrow pulse signal 2 to high-speed switch 2, which drives laser 2. At time t1, during the rising edges of the original trigger signal and the phase shift signal, narrow pulse generator 1 samples their rising edges. When the original trigger signal is high and the phase shift signal is low, narrow pulse generator 1 outputs narrow pulse signal 1, driving high-speed switch 1 to conduct, thus enabling laser 1 to generate laser light. At time t2, during the falling edges of the original trigger signal and the phase shift signal, narrow pulse generator 2 samples their falling edges. When the original trigger signal is low and the phase shift signal is high, narrow pulse generator 2 outputs narrow pulse signal 2, driving high-speed switch 2 to conduct, thus enabling laser 2 to generate laser light. By periodically generating narrow pulse signals, the alternating emission of the two lasers is achieved.
[0070] This embodiment feeds the original trigger signal and phase-shifted signal into the positive and negative terminals of two narrow pulse generators, respectively. Narrow pulse signal 1 is generated by phase shifting the rising edge of the original trigger signal and the phase-shifted signal, and narrow pulse signal 2 is generated by phase shifting the falling edge of the original trigger signal and the phase-shifted signal. This allows the device to generate dual-channel alternating narrow pulses to drive the subsequent switching chip using only one AND gate and two RC delay circuits. Because the phase-shifting circuit consists of only one AND gate and two RC delay circuits, the performance consistency and stability of the narrow pulse signals between the two channels are improved. Since there are no additional circuits required, the cost of the laser driving device is reduced, and the overall circuit size and power consumption are decreased. Furthermore, by generating two narrow pulse signals through rising edge sampling and falling edge sampling respectively, the frequency of the high-level narrow pulse signal is significantly increased.
[0071] Besides SPAD sensors, circuits or chips capable of generating PWM signals, such as MCUs and FPGAs, can also generate the original trigger signal. RC circuits and AND gates can generate phase-shift signals, and these can be replaced by FPGAs, CPLDs, and high-precision buffers. High-speed switches can be gallium nitride switches, silicon carbide switches, and MOSFETs, etc., to drive the laser to emit light alternately.
[0072] The components generating the original trigger signal, excluding the SPAD sensor, RC circuit, and AND gate, can be entirely replaced with a chip such as the SPAD chip that has a built-in precise phase-shift module, outputting both the original trigger signal and the phase-shift signal. This chip adjusts the phase difference between the original trigger signal and the phase-shift signal via registers. This embodiment relies on a purely digital chip to generate the original trigger signal and phase-shift signal, reducing circuit cost, size, and power consumption, further reducing channel delay, and improving the stability of narrow pulse signals.
[0073] Understandably, the aforementioned laser driving device can be applied not only to lidar, but also to LED lighting products, laser medical equipment, laser rangefinders, and any other product that requires light emission.
[0074] This application also provides an electronic product, which includes a laser driving device and a laser emitting component as described in any of the above embodiments; the laser driving device is connected to the laser emitting component and is used to drive the laser emitting component to generate laser light. The electronic product can be a lidar, laser medical device, or laser ranging device, etc.
[0075] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
[0076] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.
Claims
1. A laser driving device, characterized in that, The laser driving device includes: a laser driving module; the laser driving module includes: a first laser driving component and a second laser driving component; The first input terminal of the first laser driving component is connected to a first trigger signal, the second input terminal of the first laser driving component is connected to a second trigger signal, and the output terminal of the first laser driving component is connected to a first laser emitting component. The first laser driving component is used to generate a first narrow pulse signal according to the first trigger signal and the second trigger signal, and transmit the first narrow pulse signal to the first laser emitting component so that the first laser emitting component generates laser light. The first input terminal of the second laser driving component is connected to the second trigger signal, the second input terminal of the second laser driving component is connected to the first trigger signal, and the output terminal of the second laser driving component is connected to the second laser emitting component. It is used to generate a second narrow pulse signal according to the second trigger signal and the first trigger signal, and transmit the second narrow pulse signal to the second laser emitting component so that the second laser emitting component generates laser light. There is a phase difference between the first trigger signal and the second trigger signal.
2. The laser driving device according to claim 1, characterized in that, The first laser driving component is used to generate the first narrow pulse signal based on the rising edges of the first trigger signal and the second trigger signal; The second laser driving component is used to generate the second narrow pulse signal based on the first trigger signal and the falling edge of the second trigger signal.
3. The laser driving device according to claim 1, characterized in that, The first laser driving component is used to output the first narrow pulse signal when the first trigger signal is high and the second trigger signal is low; The second laser driving component is used to output the second narrow pulse signal when the second trigger signal is high and the first trigger signal is low.
4. The laser driving device according to claim 1, characterized in that, The laser driving module also includes a first high-speed switch and a second high-speed switch; The output of the first laser driving component is connected to the first laser emitting component via the first high-speed switch; The output of the second laser driving component is connected to the second laser emitting component via the second high-speed switch.
5. The laser driving device according to claim 1, characterized in that, Both the first laser driving component and the second laser driving component are narrow pulse generators; The first input terminal of the first laser driving component is the positive input terminal of the narrow pulse generator, and the second input terminal of the first laser driving component is the negative input terminal of the narrow pulse generator; The first input terminal of the second laser driving component is the positive input terminal of the narrow pulse generator, and the second input terminal of the second laser driving component is the negative input terminal of the narrow pulse generator.
6. The laser driving device according to claim 1, characterized in that, The laser driving device also includes a trigger signal generation component; The trigger signal generation component is connected to the first input terminal of the first laser driving component, the second input terminal of the first laser driving component, the first input terminal of the second laser driving component, and the second input terminal of the second laser driving component, respectively, and is used to generate the first trigger signal and the second trigger signal, and output the first trigger signal to the first input terminal of the first laser driving component and the second input terminal of the second laser driving component, respectively, and output the second trigger signal to the second input terminal of the first laser driving component and the first input terminal of the second laser driving component, respectively.
7. The laser driving device according to claim 6, characterized in that, The trigger signal generation component includes: a trigger signal element and a phase shift element; The trigger signal element is connected to the first input terminal of the first laser driving component, the second input terminal of the second laser driving component, and the phase shift element, respectively, to generate the first trigger signal and output the first trigger signal to the first input terminal of the first laser driving component, the second input terminal of the second laser driving component, and the phase shift element, respectively. The phase-shifting element is connected to the second input terminal of the first laser driving component and the first input terminal of the second laser driving component, respectively, for receiving the first trigger signal, performing phase-shifting processing on the first trigger signal to generate the second trigger signal, and outputting the second trigger signal to the second input terminal of the first laser driving component and the first input terminal of the second laser driving component.
8. The laser driving device according to claim 7, characterized in that, The phase-shifting element includes: a first delay circuit, a second delay circuit, and a shaping circuit; The first delay circuit is connected to the first input terminal of the trigger signal element and the shaping circuit respectively, and is used to receive the first trigger signal and perform delay processing on the first trigger signal to obtain the first delay signal; The second delay circuit is connected to the second input terminal of the trigger signal element and the shaping circuit respectively, and is used to receive the first trigger signal and perform delay processing on the first trigger signal to obtain the second delay signal; The output terminal of the shaping circuit is connected to the second input terminal of the first laser driving component and the first input terminal of the second laser driving component, respectively, and is used to shape the first delay signal and the second delay signal to obtain the second trigger signal.
9. The laser driving device according to claim 8, characterized in that, The shaping circuit is an AND gate shaping circuit, used to output a high level of the second trigger signal if both the rising edge voltage of the first delay signal and the rising edge voltage of the second delay signal are greater than the rising edge threshold of the AND gate; and to output a low level of the second trigger signal if either the falling edge voltage of the first delay signal or the falling edge voltage of the second delay signal is less than the falling edge threshold of the AND gate.
10. An electronic product, characterized in that, The electronic product includes the laser driving device and the laser emitting assembly as described in any one of claims 1 to 9; The laser driving device is connected to the laser emitting component and is used to drive the laser emitting component to generate laser light.