Laser ranging method and system, ranging equipment and readable storage medium

Abstract

The invention provides a laser ranging method and system, ranging equipment and a readable storage medium, and the method comprises the steps: controlling a laser emission unit to emit laser according to a first laser trigger signal, and calculating the rise time of a first histogram; superposition delay is carried out on the first laser trigger signal according to a preset superposition delay strategy, a second laser trigger signal is obtained, and single superposition delay corresponds to one unit delay; controlling the laser emission unit to emit laser according to the second laser trigger signal, and calculating the rise time of a second histogram; and under the condition that the rising time difference is greater than or equal to a preset difference threshold value, calculating a distance measurement result according to the current delay superposition times and the second histogram rising time. According to the invention, superposition delay is carried out on the laser trigger signal according to the fixed unit delay, the number of superposition delay times can be effectively reduced, the number storage space occupied by laser ranging is reduced, and the laser ranging precision is improved.

Description

Technical Field

[0001] The present invention relates to the field of laser ranging technology, and in particular to a laser ranging method, system, ranging equipment and readable storage medium. Background Art

[0002] In a LiDAR or laser ranging system, the resolution of the ranging is limited by the resolution of the time-to-digital converter (TDC) circuit integrated on the chip. The current mainstream solutions all use multiple triggering of laser pulses at a certain repetition rate, and multiple integration and superposition of the signals received by the single photon avalanche diode (SPAD), and then obtain a higher distance resolution through waveform extraction, distance measurement and other modules. In the case where the SPAD receiving signal is relatively saturated, even the superimposed signal still cannot reflect the distance information less than the TDC resolution, or due to repetition rate or power limitations, the number of superpositions is small and cannot meet the waveform requirements. Summary of the invention

[0003] In order to solve the above technical problems, the embodiments of the present application provide a laser ranging method, system, ranging device and readable storage medium that can accurately measure the distance value without complex measurement data processing logic and require processing and storage of data with a small bit width. The specific scheme is as follows: In a first aspect, an embodiment of the present application provides a laser ranging method, comprising: Controlling the laser emitting unit to emit laser according to the first laser trigger signal, and calculating the first histogram rise time according to the histogram data sent by the single photon avalanche diode chip; Performing superposition delay on the first laser trigger signal according to a preset superposition delay strategy to obtain a second laser trigger signal, wherein a single superposition delay corresponds to a unit delay; Controlling the laser emitting unit to emit laser according to the second laser trigger signal, and calculating a second histogram rise time according to the histogram data sent by the single photon avalanche diode chip; When the rise time difference is greater than or equal to the preset difference threshold, the ranging result is calculated according to the current delay superposition times and the second histogram rise time, wherein the rise time difference is the difference between the first histogram rise time and the second histogram rise time.

[0004] According to a specific implementation of the embodiment of the present application, the method further includes: When the rise time difference is less than the preset difference threshold, the step of performing superposition delay on the first laser trigger signal according to the preset superposition delay strategy to obtain a second laser trigger signal is jumped to execution until the rise time difference is equal to the preset difference threshold.

[0005] According to a specific implementation of the embodiment of the present application, controlling the laser emitting unit to emit laser according to the first laser trigger signal includes: generating a measurement synchronization signal; Sending the measurement synchronization signal to the single-photon avalanche diode chip to enable the single-photon avalanche diode chip to generate a first laser trigger signal, wherein the first laser trigger signal includes an initial delay value, and the initial delay value is greater than a time-to-digital converter resolution; The first laser trigger signal sent by the single photon avalanche diode chip is received, and the first laser trigger signal is sent to the laser emitting unit to control the laser emitting unit to emit laser.

[0006] According to a specific implementation of the embodiment of the present application, the method of superimposing and delaying the first laser trigger signal according to a preset superposition and delay strategy to obtain the second laser trigger signal includes: Get the current delay superposition times; The second laser trigger signal is obtained by subtracting the current delay superposition times unit delay from the initial delay value of the first laser trigger signal.

[0007] According to a specific implementation of the embodiment of the present application, the unit delay is the ratio of twice the minimum distance resolution to the speed of light; the maximum value of the delay superposition times is the ratio of the time-to-digital converter resolution to the unit delay.

[0008] According to a specific implementation of the embodiment of the present application, controlling the laser emitting unit to emit laser according to the second laser trigger signal includes: The second laser trigger signal is sent to the laser emitting unit to control the laser emitting unit to emit laser.

[0009] According to a specific implementation of the embodiment of the present application, the step of calculating the histogram rise time according to the histogram data sent by the single photon avalanche diode chip includes: searching for a local maximum in the histogram data; Comparing the local maximum value with a valid peak determination threshold; If the local maximum value is greater than the effective peak value judgment threshold, the time point when the local maximum value starts to rise is recorded to obtain the histogram rise time.

[0010] In a second aspect, an embodiment of the present application provides a laser ranging system, comprising: a field programmable gate array, a single photon avalanche diode chip, and a laser emission unit; The single photon avalanche diode chip is used to send histogram data to the field programmable gate array; The laser emitting unit is used to emit laser according to the laser trigger signal; The field programmable gate array is used to execute the laser ranging method described in the first aspect.

[0011] In a third aspect, an embodiment of the present application provides a ranging device, the ranging device comprising: at least one processor; and, a memory communicatively connected to the at least one processor; wherein, The memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the laser ranging method described in the first aspect.

[0012] In a fourth aspect, an embodiment of the present application further provides a non-transitory computer-readable storage medium, which stores computer instructions, and the computer instructions are used to enable the computer to execute the laser ranging method described in the first aspect.

[0013] In summary, the present embodiment provides a laser ranging method, system, ranging device and readable storage medium, including: controlling a laser emitting unit to emit laser according to a first laser trigger signal, and calculating the rise time of a first histogram; superimposing and delaying the first laser trigger signal according to a preset superposition delay strategy to obtain a second laser trigger signal, wherein a single superposition delay corresponds to a unit delay; controlling the laser emitting unit to emit laser according to the second laser trigger signal, and calculating the rise time of a second histogram; when the rise time difference is greater than or equal to a preset difference threshold, calculating the ranging result according to the current delay superposition times and the second histogram rise time. The present application superimposes and delays the laser trigger signal according to a fixed unit delay, which can effectively reduce the number of superposition delays, reduce the amount of storage occupied by laser ranging, and improve the accuracy of laser ranging. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0015] Figure 1A module block diagram of a laser ranging system provided in an embodiment of the present application; Figure 2 A schematic diagram of a laser ranging method according to an embodiment of the present invention; Figure 3 A schematic flow chart of the steps of obtaining a second laser trigger signal by superimposing a delay provided in an embodiment of the present application; Figure 4 A schematic diagram of a superposition delay strategy provided in an embodiment of the present application; Figure 5 A schematic diagram of the process flow for obtaining the histogram rise time provided in an embodiment of the present application. DETAILED DESCRIPTION

[0016] The embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0017] The following describes the implementation methods of the present application through specific examples, and those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The present application can also be implemented or applied through other different specific implementation methods, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that, in the absence of conflict, the following embodiments and the features in the embodiments can be combined with each other. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without making creative work belong to the scope of protection of the present application.

[0018] It should be noted that various aspects of the embodiments within the scope of the appended claims are described below. It should be apparent that the aspects described herein may be embodied in a wide variety of forms, and any specific structure and / or function described herein is merely illustrative. Based on the present application, it should be understood by those skilled in the art that an aspect described herein may be implemented independently of any other aspect, and two or more of these aspects may be combined in various ways. For example, any number of aspects described herein may be used to implement the device and / or practice the method. In addition, other structures and / or functionalities other than one or more of the aspects described herein may be used to implement this device and / or practice this method.

[0019] It should also be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present application. The drawings only show components related to the present application rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0020] Additionally, in the following description, specific details are provided to facilitate a thorough understanding of the examples. However, it will be understood by those skilled in the art that the aspects described may be practiced without these specific details.

[0021] refer to Figure 1 , an embodiment of the present application provides a laser ranging system, including: a field programmable gate array (Field Programmable Gate Array, referred to as FPGA), a single photon avalanche diode (Single Photon Avalanche Diode, referred to as SPAD) chip and a laser emitting unit. In this embodiment, the laser emitting unit can be a vertical cavity surface emitting laser (Vertical-Cavity Surface-Emitting Laser, referred to as VCSEL laser). It should be noted that the laser emitting unit can also select a suitable laser emitter according to the needs of the actual application scenario.

[0022] In this embodiment, when the laser ranging system performs the laser ranging step, the FPGA will send a measurement synchronization signal to the SPAD chip during each measurement process, so that the SPAD chip starts according to the measurement synchronization signal. After a fixed delay, the SPAD generates a laser trigger signal and sends the laser trigger signal to the FPGA, which is forwarded by the FPGA to the VCSEL laser to control the VCSEL laser to emit a laser signal to the target to be measured. The surface of the target to be measured reflects the laser signal, and the SPAD chip generates a corresponding photon count histogram after receiving the echo signal corresponding to the laser signal. The SPAD chip sends a photon count histogram to the FPGA, so that the FPGA starts to perform superposition delay processing on the laser trigger signal to obtain a superposition delay signal. The FPGA sends a superposition delay signal to the VCSEL laser, so that the VCSEL laser emits a laser according to the superposition delay signal.

[0023] The FPGA repeatedly performs superposition delay processing on the laser trigger signal until the rising time point of the received photon count histogram shifts, and determines that the laser ranging step is completed. The measurement result is calculated based on the execution parameters of the laser ranging step.

[0024] The laser ranging system provided in this embodiment can complete laser ranging with less energy consumption, and has higher laser ranging accuracy and requires less storage data. The laser ranging method performed by the laser ranging system provided in this embodiment is described in more detail below.

[0025] refer to Figure 2 The embodiment of the present application provides a laser ranging method, which is described by taking the method applied to the FPGA of the ranging device as an example, including the following steps: S201, controlling a laser emitting unit to emit laser according to a first laser trigger signal, and calculating a first histogram rise time according to histogram data sent by a single photon avalanche diode chip.

[0026] S202, superimposing and delaying the first laser trigger signal according to a preset superimposing and delaying strategy to obtain a second laser trigger signal, wherein a single superimposing and delaying corresponds to a unit delay.

[0027] S203, controlling the laser emitting unit to emit laser according to the second laser trigger signal, and calculating the second histogram rise time according to the histogram data sent by the single photon avalanche diode chip.

[0028] S204, when the rise time difference is greater than or equal to a preset difference threshold, a ranging result is calculated according to the current delay superposition times and the rise time of the second histogram, wherein the rise time difference is the difference between the rise time of the first histogram and the rise time of the second histogram.

[0029] In this embodiment, the first laser trigger signal is the initial laser trigger signal sent by the SPAD chip to the FPGA, that is, the laser trigger signal with an initial delay value generated by the SPAD chip according to the measurement synchronization signal sent by the FPGA. The FPGA controls the laser emission unit to emit the laser according to the first laser trigger signal, and receives the histogram data collected by the SPAD chip during this laser emission process, and calculates the first histogram rise time according to the histogram data. It should be noted that the histogram rise time is the time when the target peak in the histogram data starts to rise. The target peak in this embodiment is a preset local maximum value of the histogram that is greater than the preset effective peak judgment threshold.

[0030] The preset superposition delay strategy includes, after recording and obtaining the rise time of the first histogram, starting to decrement the initial delay value of the first laser trigger signal. In a specific embodiment, a single delay step corresponds to a unit delay. In this embodiment, the initial delay value of the first laser trigger signal is repeatedly superimposed with multiple decrement delays, and each superposition delay corresponds to a decrement of one unit delay.

[0031] After each superimposed delay step, that is, each decremental delay step, a second laser trigger signal is generated. According to the second laser trigger signal, that is, the superimposed delay signal, the FPGA controls the VCSEL laser to emit laser light to perform the laser ranging step.

[0032] In this embodiment, when the rise time difference is less than the preset difference threshold, the step of jumping to execute the step of superimposing and delaying the first laser trigger signal according to the preset superimposition delay strategy to obtain the second laser trigger signal is performed until the rise time difference is equal to the preset difference threshold.

[0033] That is, when the rise time difference is less than the preset difference threshold, steps S102-S103 are repeated until the difference between the rise time of the first histogram and the rise time of the second histogram is greater than or equal to the preset difference threshold. At this time, the ranging result of this laser ranging step is calculated according to the number of executions of the current superposition delay step, that is, the current delay superposition number, and the second histogram rise time recorded in the current superposition delay step.

[0034] In actual application, when the recorded histogram rise time changes from the first histogram rise time T to the second histogram rise time T-1, it is determined that the histogram rise time has completed the offset, and the fine ranging value is calculated according to the current number of superposition delays n and the second histogram rise time T-1. The ranging value calculation formula is: d=(T-1+n*Δt)*c / 2, where n is an integer greater than or equal to 0, and c is the speed of light.

[0035] In summary, unlike the related art in which waveform delay is generated by time jitter or passive delay of the laser trigger signal, after waveform delay is superimposed, a more precise distance measurement value is extracted from the morphological characteristics of the waveform (complex logic processing and large storage data bit width). This embodiment provides a laser ranging method, which can achieve laser ranging by superimposing a fixed unit delay and a small number of superimposed delays, and the measurement logic processing is relatively simple, and the storage data bit width is smaller.

[0036] According to a specific implementation of the embodiment of the present application, Figure 3 As shown, controlling the laser emitting unit to emit laser according to the first laser trigger signal includes: S301, generating a measurement synchronization signal.

[0037] S302, sending a measurement synchronization signal to the single photon avalanche diode chip to enable the single photon avalanche diode chip to generate a first laser trigger signal, wherein the first laser trigger signal includes an initial delay value, and the initial delay value is greater than a resolution of a time-to-digital converter.

[0038] S303, receiving a first laser trigger signal sent by the single photon avalanche diode chip, and sending the first laser trigger signal to a laser emitting unit to control the laser emitting unit to emit laser.

[0039] In this embodiment, the initial delay value t of the first laser trigger signal generated by the SPAD chip should be at least greater than the time-to-digital converter (TDC) circuit resolution t0, that is, t>t0. It should be noted that the TDC resolution can be determined according to the actual structure of the TDC circuit in the actual application scenario and the application needs.

[0040] In this embodiment, after sending the first laser trigger signal to the laser emitting unit to control the laser emitting unit to emit laser, the decremental delay processing is repeatedly performed on the first laser trigger signal. In each decremental delay processing, the initial delay value t is decremented by one unit time Δt until the initial delay value t is decremented to the TDC resolution t0.

[0041] According to a specific implementation of the embodiment of the present application, Figure 3 As shown, the first laser trigger signal is superimposed and delayed according to a preset superposition delay strategy to obtain a second laser trigger signal, including: S301, obtaining the current delay superposition times.

[0042] S302, based on the initial delay value of the first laser trigger signal, subtract the current delay superposition times of unit delay to obtain a second laser trigger signal.

[0043] In this embodiment, if Figure 4 As shown, when the first laser trigger signal is generated, the delay value corresponding to the first laser trigger signal is the initial delay value t. Each subsequent execution of the superposition delay step will obtain the current delay superposition number n, where n is an integer greater than or equal to 0. Then, based on the initial delay value t, the delay value of the second laser trigger signal is obtained by subtracting the current delay superposition number of unit delays Δt.

[0044] It should be noted that the delay value of the second laser trigger signal can be expressed as t-nΔt.

[0045] According to a specific implementation of the embodiment of the present application, the unit delay is the ratio of twice the minimum distance resolution to the speed of light; the maximum value of the delay superposition times is the ratio of the time-to-digital converter resolution to the unit delay.

[0046] In this embodiment, the unit delay needs to satisfy Δt=minimum distance resolution×2 / speed of light c. For example, if the TDC resolution is 1ns and the minimum distance resolution is 3cm, then Δt=3cm×2 / c=0.2ns. It should be noted that the minimum distance resolution is determined according to the structure of the TDC circuit and the application requirements in the actual application scenario and is not limited here.

[0047] According to a specific implementation of the embodiment of the present application, controlling the laser emitting unit to emit laser according to the second laser trigger signal includes: A second laser trigger signal is sent to the laser emitting unit to control the laser emitting unit to emit laser.

[0048] In this embodiment, the execution process of step S203 is that the FPGA delays the laser trigger signal of the previous laser emission step to obtain a second laser trigger signal, and then sends the second laser trigger signal to the VCSEL laser to enable the VCSEL laser to emit laser.

[0049] It should be noted that the delay logic in this embodiment can be implemented by using the IO delay resources inside the FPGA.

[0050] According to a specific implementation of the embodiment of the present application, Figure 5 As shown, the steps of calculating the histogram rise time according to the histogram data sent by the single photon avalanche diode chip include: S501, searching for a local maximum in the histogram data.

[0051] S502, comparing the local maximum value with the effective peak determination threshold.

[0052] S503: If the local maximum value is greater than the effective peak value judgment threshold, the time point when the local maximum value starts to rise is recorded to obtain the histogram rise time.

[0053] In this embodiment, a peak is searched in each completed histogram (SPAD chip collects echo signals to generate histogram data) to find the local maximum value in the histogram. It should be noted that the local maximum value can be a single maximum value or multiple maximum values. The number of local maximum values ​​is determined according to the actual situation of the histogram data.

[0054] The local maximum value found is compared with the set effective peak judgment threshold, where the specific value of the effective peak judgment threshold needs to be determined according to the application requirements of the application scenario. When the local maximum value is greater than the effective peak judgment threshold, the local maximum value is the effective peak value, and the time point when the effective peak value starts to rise is extracted, that is, the histogram rise time. It should be noted that the energy distribution reflected on the histogram is related to the pulse width and shape of the laser pulse. If the rising edge point and the peak point are not saturated, there will be a certain interval.

[0055] In summary, the present embodiment provides a laser ranging method, which can complete laser ranging with less energy consumption, without the need to perform complex and multiple time superposition delay processing, without the need to set waveform delay, and effectively simplifying the laser ranging logic. The theoretical maximum number of delay superposition times in the present embodiment is the ratio of the TDC resolution to the unit delay, that is, t0 / Δt. The laser ranging method provided in the present embodiment can flexibly adjust the number of delay superposition times by adjusting the unit delay, thereby providing higher laser ranging accuracy and occupying less storage resources.

[0056] In addition, an embodiment of the present application further provides a distance measuring device, the distance measuring device comprising: at least one processor; and, a memory communicatively connected to the at least one processor; wherein, The memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the laser ranging method in the aforementioned method embodiment.

[0057] An embodiment of the present application also provides a non-transitory computer-readable storage medium, which stores computer instructions, and the computer instructions are used to enable the computer to execute the laser ranging method in the aforementioned method embodiment.

[0058] It should be noted that the computer-readable medium mentioned above in the present application may be a computer-readable signal medium or a computer-readable storage medium or any combination of the above two. The computer-readable storage medium may be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device or device, or any combination of the above. More specific examples of computer-readable storage media may include, but are not limited to: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above.

[0059] In the present application, a computer-readable storage medium may be any tangible medium containing or storing a program that can be used by or in combination with an instruction execution system, apparatus, or device. In the present application, a computer-readable signal medium may include a data signal propagated in a baseband or as part of a carrier wave, which carries a computer-readable program code. Such propagated data signals may take a variety of forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination of the above. A computer-readable signal medium may also be any computer-readable medium other than a computer-readable storage medium, which may send, propagate, or transmit a program for use by or in combination with an instruction execution system, apparatus, or device. The program code contained on a computer-readable storage medium may be transmitted using any suitable medium, including but not limited to: wires, optical cables, RF (radio frequency), etc., or any suitable combination of the above.

[0060] The computer-readable medium may be included in the distance measuring device; or may exist independently without being assembled into the distance measuring device.

[0061] The computer-readable medium carries one or more programs. When the one or more programs are executed by the ranging device, the ranging device: controls the laser emitting unit to emit laser according to the first laser trigger signal, and calculates the first histogram rise time according to the histogram data sent by the single-photon avalanche diode chip; superimposes and delays the first laser trigger signal according to a preset superposition delay strategy to obtain a second laser trigger signal, wherein a single superposition delay corresponds to a unit delay; controls the laser emitting unit to emit laser according to the second laser trigger signal, and calculates the second histogram rise time according to the histogram data sent by the single-photon avalanche diode chip; when the rise time difference is greater than or equal to the preset difference threshold, calculates the ranging result according to the current delay superposition times and the second histogram rise time, wherein the rise time difference is the difference between the first histogram rise time and the second histogram rise time.

[0062] The flow chart and block diagram in the accompanying drawings illustrate the possible architecture, function and operation of the system, method and computer program product according to various embodiments of the present application. In this regard, each square box in the flow chart or block diagram can represent a module, a program segment or a part of a code, and the module, the program segment or a part of the code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the square box can also occur in a sequence different from that marked in the accompanying drawings. For example, two square boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each square box in the block diagram and / or flow chart, and the combination of the square boxes in the block diagram and / or flow chart can be implemented with a dedicated hardware-based system that performs a specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions.

[0063] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A laser ranging method, characterized in that: include: Controlling the laser emitting unit to emit laser according to the first laser trigger signal, and calculating the first histogram rise time according to the histogram data sent by the single photon avalanche diode chip; Performing superposition delay on the first laser trigger signal according to a preset superposition delay strategy to obtain a second laser trigger signal, wherein a single superposition delay corresponds to a unit delay; Controlling the laser emitting unit to emit laser according to the second laser trigger signal, and calculating a second histogram rise time according to the histogram data sent by the single photon avalanche diode chip; When the rise time difference is greater than or equal to the preset difference threshold, the ranging result is calculated according to the current delay superposition times and the second histogram rise time, wherein the rise time difference is the difference between the first histogram rise time and the second histogram rise time.

2. The method according to claim 1, characterized in that The method further comprises: When the rise time difference is less than the preset difference threshold, the step of performing superposition delay on the first laser trigger signal according to the preset superposition delay strategy to obtain a second laser trigger signal is jumped to execution until the rise time difference is equal to the preset difference threshold.

3. The method according to claim 1, characterized in that The step of controlling the laser emitting unit to emit laser according to the first laser trigger signal comprises: generating a measurement synchronization signal; Sending the measurement synchronization signal to the single-photon avalanche diode chip to enable the single-photon avalanche diode chip to generate a first laser trigger signal, wherein the first laser trigger signal includes an initial delay value, and the initial delay value is greater than a time-to-digital converter resolution; The first laser trigger signal sent by the single-photon avalanche diode chip is received, and the first laser trigger signal is sent to the laser emitting unit to control the laser emitting unit to emit laser.

4. The method according to claim 3, characterized in that The method of superimposing and delaying the first laser trigger signal according to a preset superimposition and delay strategy to obtain a second laser trigger signal includes: Get the current delay superposition times; The second laser trigger signal is obtained by subtracting the current delay superposition times unit delay from the initial delay value of the first laser trigger signal.

5. The method according to claim 4, characterized in that The unit delay is the ratio of twice the minimum distance resolution to the speed of light; the maximum value of the delay superposition times is the ratio of the time-to-digital converter resolution to the unit delay.

6. The method according to claim 1, characterized in that The step of controlling the laser emitting unit to emit laser according to the second laser trigger signal comprises: The second laser trigger signal is sent to the laser emitting unit to control the laser emitting unit to emit laser.

7. The method according to claim 1, characterized in that The steps of calculating the histogram rise time according to the histogram data sent by the single photon avalanche diode chip include: searching for a local maximum in the histogram data; Comparing the local maximum value with a valid peak determination threshold; If the local maximum value is greater than the effective peak value judgment threshold, the time point when the local maximum value starts to rise is recorded to obtain the histogram rise time.

8. A laser ranging system, characterized in that: Including: field programmable gate array, single photon avalanche diode chip and laser emission unit; The single photon avalanche diode chip is used to send histogram data to the field programmable gate array; The laser emitting unit is used to emit laser according to the laser trigger signal; The field programmable gate array is used to execute the laser ranging method described in any one of claims 1-7.

9. A distance measuring device, characterized in that: include: at least one processor; as well as, a memory communicatively connected to the at least one processor; wherein, The memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to execute the laser ranging method described in any one of claims 1-7.

10. A non-transitory computer-readable storage medium, characterized in that: The non-transitory computer-readable storage medium stores computer instructions, which are used to enable the computer to execute the laser ranging method described in any one of claims 1-7.

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