Scanning method for inhibiting SPAD optical crosstalk of ranging chip

Abstract

The invention provides a scanning method for inhibiting SPAD optical crosstalk of a ranging chip, and the method comprises the steps: defining a horizontal partitioning mode of an SPAD array, shielding SPAD units which do not need to be started according to the partitioning mode, and releasing SPAD units which need to be started; according to the method, an SPAD array is divided into Area and SLOT in the vertical direction, a scanning mode is selected, an initial table is configured before SPAD scanning is started according to a defined partitioning mode and the scanning mode, SPAD units in all partitions are started in sequence to enable the SPAD units to receive laser, and the purpose of restraining optical crosstalk between the SPAD units is achieved by dynamically controlling starting of the SPAD units.

Description

Technical Field

[0001] This application relates to the field of ranging technology, and particularly to a scanning method for suppressing SPAD optical crosstalk of a ranging chip. Background Art

[0002] SPAD (Single Photon Avalanche Diodes) single photon avalanche diode is a highly sensitive photodetector that can detect single photons under extremely low light conditions. Its basic working principle is to utilize the avalanche breakdown effect to amplify weak optical signals into detectable electrical signals. In a lidar system, SPAD can achieve high-precision distance measurement and high-speed data acquisition, significantly improving the detection range and resolution of the system. Usually, a SPAD array composed of multiple SPAD pixel units is used for ranging.

[0003] Currently, when the SPAD array is working, its detection mode is the frame frequency synchronization mode, that is, all SPAD pixels enter the avalanche standby state simultaneously, resulting in optical crosstalk between adjacent SPAD pixels, thereby affecting the detection imaging quality. Summary of the Invention

[0004] In view of this, the present invention proposes a scanning method for suppressing SPAD optical crosstalk of a ranging chip. The scanning method includes: determining a partitioning mode according to the pixel points in the horizontal direction of the SPAD array, and performing partitioning control on the SPAD array according to the partitioning mode; determining the scanning target in the vertical direction of the SPAD array, and configuring the scanning mode according to the partitioning mode and the scanning target; configuring an initial table according to the scanning mode, and sequentially turning on the SPAD units in the scanning target to receive laser according to the initial table information to complete the scanning.

[0005] Preferably, the partitioning mode includes: a first partitioning mode, in which the SPAD array is further configured to include a plurality of large regions, and each large region includes a plurality of small regions; or, a second partitioning mode.

[0006] Preferably, the performing partitioning control on the SPAD array according to the partitioning mode includes, in the first partitioning mode, configuring a first initial value and a first moving step length for the large regions of the SPAD array, and simultaneously configuring a second initial value and a second moving step length for the small regions. After cycling through all the large regions according to the trigger signal according to the first initial value and the first moving step length, cycling through the small regions according to the second initial value and the second moving step length; in the second partitioning mode, performing partitioning control through an external selection register.

[0007] Preferably, determining the scanning target in the vertical direction of the SPAD array includes: the SPAD array is further configured into a plurality of scanning regions in the vertical direction, each scanning region is configured into a plurality of scanning blocks, and the scanning target is configured through a register.

[0008] Preferably, the scanning mode includes at least one of the following: general mode, moving mode, ROI mode, and reverse moving mode.

[0009] Preferably, the SPAD units in each scanning block within the current scanning region are sequentially turned on for scanning according to the partition control method of the current scanning region, and the next scanning region to be scanned is switched through register configuration, and scanning is performed according to the partition control method within the next scanning region until all scanning targets are scanned.

[0010] Preferably, the initial table information includes: data representing the turn-on states of the SPAD units in the scanning region and the scanning block, where the lower bits of the initial table control the SPAD units on the left, and the higher bits control the SPAD units on the right.

[0011] Preferably, configuring the initial table according to the scanning mode includes: in the general mode, configuring the starting position, ending position, and scanning order of the SPAD units to be turned on; in the moving mode, configuring the number of rows and columns of the SPAD units to be turned on through an external communication bus or an MCU; in the ROI mode, configuring the ROI region in the initial table; in the reverse moving mode, configuring the starting position, ending position, and reverse scanning order of the SPAD units to be turned on.

[0012] The present invention also provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the scanning method described in any one of the above is implemented.

[0013] The scanning method for suppressing the SPAD optical crosstalk of a ranging chip provided by the present invention divides the SPAD array into multiple sub-arrays in the horizontal and vertical directions, selects a scanning mode according to the spatial distribution characteristics of the crosstalk, and selectively turns on each SPAD, which can effectively avoid the optical crosstalk to adjacent SPADs caused by all SPADs entering the avalanche standby state simultaneously in the traditional frame frequency synchronization mode, thereby avoiding the influence of crosstalk on the detection imaging quality to the greatest extent. Description of the Drawings

[0014] To more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0015] Figure 1 It is a flowchart of a scanning method for suppressing SPAD optical crosstalk of a ranging chip provided by an embodiment of the present application;

[0016] Figure 2 It is a schematic diagram of a macro pixel in an embodiment of the present application;

[0017] Figure 3 It is a schematic diagram of the horizontal direction partitioning mode of the SPAD array in an embodiment of the present application;

[0018] Figure 4 It is a schematic diagram of a second partitioning mode provided by an embodiment of the present application;

[0019] Figure 5 It is a schematic diagram of a first partitioning mode provided by an embodiment of the present application;

[0020] Figure 6 It is a timing diagram of the trigger signal provided by an embodiment of the present application;

[0021] Figure 7 It is a schematic diagram of the vertical partitioning of the SPAD array provided by an embodiment of the present application;

[0022] Figure 8 It is a schematic diagram of the scanning mode provided by an embodiment of the present application;

[0023] Figure 9 It is a schematic diagram of the initial state provided by an embodiment of the present application. Detailed implementation manners

[0024] The following will describe the specific implementation manners of the present invention in more detail with reference to the schematic diagrams. According to the following description, the advantages and features of the present invention will be clearer. It should be noted that the drawings are all in a very simplified form and use non-precise scales, only for the purpose of facilitating and clearly assisting in explaining the purpose of the embodiments of the present invention.

[0025] In the description of this application, the terms "first", "second", "third", etc. (if any) in the specification, claims, and drawings of this application are used to distinguish similar objects and do not necessarily describe a specific order or sequence. It should be understood that the described objects can be interchanged under appropriate circumstances. The meaning of the "initial table" is a data table defined through an external communication bus or MCU before starting the SPAD array scan, which is used to initialize the scan configuration. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. Some of the block diagrams shown in the drawings are functional entities and do not necessarily correspond to physically or logically independent entities.

[0026] In the description of this application, it should be understood that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. This is only for the convenience of describing this application and simplifying the description, rather than indicating or implying that the device or component referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to this application.

[0027] To make the purpose, features, and advantages of this application more obvious and understandable, the following further describes this application in detail with reference to the drawings and specific embodiments.

[0028] The embodiment of this application provides a scanning method for suppressing the SPAD optical crosstalk of a ranging chip, which partitions the SPAD array in the horizontal and vertical directions and defines the scanning mode. Through this method, the SPAD array can be lit sequentially according to the set timing, and the number of times each area is lit is uniform. Thus, it effectively avoids the optical crosstalk to adjacent SPADs caused by all SPADs entering the avalanche standby state simultaneously in the traditional frame rate synchronization mode.

[0029] Please refer to Figure 1 as shown, which is a flowchart of the scanning method for suppressing the SPAD optical crosstalk of a ranging chip provided by the embodiment of this application. The method includes:

[0030] S100: Determine the partitioning mode according to the pixel points in the horizontal direction of the SPAD array, and perform partitioning control on the SPAD array according to the partitioning mode.

[0031] In the embodiment of this application, the horizontal partitioning mode of the SPAD is defined by the pixel points in the horizontal direction of the SPAD array. According to the partitioning mode, the SPAD units that do not need to be turned on are masked, and the SPAD units that need to be turned on are released. By dynamically controlling the enabling of the SPAD units, the purpose of suppressing the optical crosstalk between the SPAD units is achieved.

[0032] The SPAD array set in the embodiment of the present application includes 576 columns * 432 rows of SPADs, and the SPAD array is composed of macro pixels (MPs, Macro Pixel). Figure 2 This is a schematic diagram of a macro pixel in the embodiment of the present application. One MP is composed of 9 SPADs. The center is a SPAD unit with 1 / 20 attenuation, and 8 fully open SPAD units surround it. These 8 SPAD units are required when the ranging chip performs ranging.

[0033] Please refer to Figure 3 As shown, this is a schematic diagram of the horizontal direction partitioning mode of the SPAD array in the embodiment of the present application. The horizontal direction partitioning mode includes a first partitioning mode and a second partitioning mode. The partitioning mode can be configured through a selection register. The trigger signal output by the TDC (Time to Digital Converter) to the LD (Laser Diode) driver will be shielded by the corresponding shielding signal. After completing the horizontal partitioning, the SPADs to be lit can be selected through the MP EN (enable) register and the SPAD EN register.

[0034] The second partitioning mode includes partitioning into 12 or less, and the partitioning control can be performed through an external selection register. Refer to Figure 3 , LD NUM = 0, "0" represents no partitioning, including 1 SPAD sub-array, and each sub-array has 576 columns of SPAD pixel units; "1" represents partitioning into 2 areas, including 2 SPAD sub-arrays, and each sub-array has 288 columns of SPAD pixel units; "2" represents partitioning into 4 areas, including 4 SPAD sub-arrays, and each sub-array has 144 columns of SPAD pixel units. "3" represents partitioning into 8 areas, including 8 SPAD sub-arrays, and each sub-array includes 72 columns of SPAD pixel units. "4" represents partitioning into 12 areas, including 12 SPAD sub-arrays, and each SPAD sub-array includes 48 columns of SPAD pixel units.

[0035] For example, when the external selection register controls the horizontal partitioning into 4 areas, please refer to Figure 4 As shown, Figure 4 This is a schematic diagram of the second partitioning mode provided by the embodiment of the present application, that is, a schematic diagram of the horizontal partitioning LD12. After partitioning, each SPAD sub-array will be lit in sequence from 0 to 3, and the number of times each area is lit is uniform.

[0036] The first partitioning mode includes partitioning into 24, and the partitioning control can be performed through an external selection register. Figure 5 This is a schematic diagram of the first partitioning mode in the embodiment of the present application. Refer to Figure 3 And Figure 5, first, the SPAD array is divided into 24 SPAD sub-arrays in the horizontal direction, and each SPAD sub-array is further configured as a large area composed of 24 columns of SPAD pixel units. Subsequently, each large area is subdivided into 8 small areas, and each small area is of 1 MP size. The purpose of configuring the large area and the small area is to refine the timing and facilitate the separate control of each area of the SPAD. When adopting the first partitioning mode, first, the initial values of the large area and the small area need to be configured. First, configure the first initial value of the large area, i.e., the 24-partition, as ’h030303. In the figure, the blue area is selected, that is, the SPAD sub-arrays numbered 0, 1, 8, 9, 16, and 17 are selected, which are the areas selected when the first TDC sends a trigger signal to the LD driver. When the next trigger signal is sent, the 24 areas of the large area will move. Then configure the first initial value of the above-mentioned 8-partition small area as ’h2, which means that the first 4 SPAD pixel units in the sub-array are selected, that is, the 0th, 1st, 2nd, and 3rd pixel units in the 0th, 1st, 8th, 9th, 16th, and 17th rows are selected, and the rest of the SPAD pixel units are turned off. Secondly, the moving step lengths of the large area and the small area need to be configured. The first moving step length of the 24-partition large area is configured through the LD24_DIV_SHIFT register. In this embodiment, this register is configured as 2, that is, the first moving step length is 2. Then, each time a trigger occurs, the selected SPAD sub-arrays in the 24 partitions of the large area move 2 areas to the right as a whole, and at this time the small area remains unchanged. It can be seen that after 4 triggers, the 24 areas of the large area move back to the area selected for the first time, that is, the large area completes one cycle. The moving step length of the small area is configured through the SDIV_SHIFT_PERIOD register. In this embodiment, this register is configured as 1. After the large area completes one cycle, the small area is triggered to start cycling. Therefore, at the fifth trigger, the large area is the same as the first time, and the small area moves 4 MP positions to the right, that is, the SPAD sub-arrays in the 0th, 1st, 8th, 9th, 16th, and 17th rows are selected, and the column area moves 4 MP positions to the right, that is, the 4th, 5th, 6th, and 7th columns in the 0th, 1st, 8th, 9th, 16th, and 17th rows are selected. Triggered in turn until after the 8th trigger, all cycles of the large and small areas are completed, and the number of times each area is lit is uniform.

[0037] Figure 6 The timing diagram of the trigger signal provided by the embodiment of the present application is shown in Figure 6, TRG_I is a periodic Tx trigger signal sent by the host computer to the ranging chip. Its source is an external MCU, and its purpose is to turn on the SPAD in the corresponding area and trigger the LDdriver to make the laser emitter emit laser. After a period of delay in the ranging chip, this signal turns on the SPAD in the corresponding area, enabling it to receive photons reflected back after detecting an object with the laser. Subsequently, the ranging chip generates TRG_O0 and TRG_O1 signals, which are used to trigger the LD driver to make the laser emitter emit laser. The TDC obtains the distance of the object by acquiring the time when the TRG_O0 and TRG_O1 signals are emitted and the time when the SPAD receives the photons reflected back from the object. After completing the horizontal partitioning, the ranging chip uses TRG_O0 and TRG_O1 as trigger signals to trigger the movement of each large horizontal area or small horizontal area. In addition, the TRG_O0 and TRG_O1 signals can be controlled through registers to mask the SPAD units that do not need to be turned on and release the SPAD units that need to be turned on.

[0038] S200: Determine the scanning target in the vertical direction of the SPAD array, and configure the scanning mode according to the partitioning mode and the scanning target.

[0039] In the embodiment of the present application, the SPAD array is further configured into several scanning areas Area in the vertical direction, and each scanning area Area is configured into several scanning blocks SLOT. The scanning target is configured through registers, that is, the target Area and SLOT can be configured through registers.

[0040] The SPAD array set in the embodiment of the present application includes 576 columns * 432 rows of SPADs. The SPAD array can be divided in the vertical direction. For example, the SPAD array is divided into 12 Areas in the vertical direction, and each Area corresponds to 576 columns * 36 rows of SPAD units. Scanning different Areas is configured by a 12-bit register Area selection register. Figure 7 For the schematic diagram of the vertical partitioning of the SPAD array provided by the embodiment of the present application, see Figure 7 , continue to subdivide the Area. The SPAD array is divided into 6 SLOTs in the vertical direction, namely SLOT 0, SLOT 1, SLOT 2, SLOT 3, SLOT 4, and SLOT 5. Each SLOT includes 2 rows of SPAD arrays, corresponding to 576 columns * 6 rows of SPADs. After setting the initial table and scanning method, different SLOTs can be selected to be lit.

[0041] The scanning modes include at least one of the following: general mode, moving mode, ROI mode, and reverse moving mode. The scanning area is composed of scanning blocks. After scanning all the scanning blocks within a scanning area, the next scanning area to be scanned is switched through register configuration until all scanning targets are scanned. After completing the partitioning in the horizontal and vertical directions, at least one of the above scanning modes needs to be configured through an external register. Figure 8 For the schematic diagram of the scanning mode provided by the embodiment of this application, please refer to Figure 8 , in the general mode, scanning is performed by moving from bottom to top in units of SLOTs, that is, SLOT 0, SLOT 1, SLOT 2, SLOT 3, SLOT 4, and SLOT 5 are sequentially turned on, and triggering and cycling are performed within each SLOT according to the preset horizontal partitioning method. After scanning 6 SLOTs, switch to the next Area by switching the Area selection register and perform scanning in the same way. That is, cyclic scanning is performed in groups of 6 SLOTs, and after scanning 72 SLOTs, a frame of data can be obtained.

[0042] In the moving mode, the initial table information needs to be configured on the host computer according to the scanning requirements, and the SPAD array is scanned sequentially according to the initial table information. For example, turn on columns 4, 5, 6, 22, 23, and 24 of MP in SLOT 0 of the first Area, columns 1, 2, 3, 7, 8, 9, 19, 20, and 21 of MP in SLOT 1, columns 10, 11, 12, 16, 17, and 18 of MP in SLOT 2, and columns 13, 14, and 15 of MP in SLOT 3. After the above areas are turned on, keep the number of turned-on MP columns unchanged, increment the SLOT number to complete the scanning of the moving mode in one Area. It should be noted that if the incremented SLOT number exceeds 5, the incremented SLOT number is modulo 6 to obtain the SLOT number applied to the current Area. In addition, to improve the scanning efficiency, two rows are scanned each time, and only the even rows need to be configured in the actual initial table, and the odd rows are automatically the same as the even rows.

[0043] The ROI mode also requires the configuration of the initial table. This mode is a sub-mode of the general mode and the mobile mode. If the general mode is selected, the ROI configuration in this mode is to change the scanning start point and end point in the vertical direction, and configure the starting SLOT. For example, configure the starting SLOT as SLOT 0, the scanning start point as the 3rd MP of SLOT 0, and the scanning end point as the 22nd MP of SLOT 0. After completing the configuration of the initial table, the SPADs in the ROI are scanned in the scanning order from bottom to top. If the mobile mode is selected, the ROI area is defined in the initial table. For example, turn on the MPs in columns 3, 4, and 5 of SLOT 0, the MPs in columns 6, 7, and 8 of SLOT 1, and the MPs in columns 9, 10, and 11 of SLOT 2. After turning on the above areas, keep the number of turned-on MP columns unchanged, and increment the SLOT number to complete the mobile mode scanning of one Area. It should be noted that if the incremented SLOT number exceeds 5, the incremented SLOT number is taken modulo 6 to obtain the SLOT number applied to the current Area.

[0044] The reverse mobile mode scans in the reverse scanning order of the general mode. For example, it moves from top to bottom in units of SLOT for scanning, that is, SLOT 5, SLOT 4, SLOT 3, SLOT 2, SLOT 1, and SLOT 0 are turned on in sequence. Inside each SLOT, triggering and cycling are performed according to the preset horizontal partition mode. The method of switching Areas is the same as that of the general mode. After completing the scanning of 6 SLOTs, switch to the next Area by switching the Area selection register and scan in the same way. That is, it cycles and scans in a horizontal partition mode with 6 SLOTs as a group in sequence. After completing the scanning of 72 SLOTs, a frame of data can be obtained.

[0045] S300: Configure the initial table according to the scanning mode, and turn on the SPAD units in the scanning target in sequence according to the initial table information to make them receive laser, and complete the scanning.

[0046] In the embodiments of the present application, the SPAD units in each scan block within the current scan area are sequentially enabled according to the partition control method of the current scan area for scanning, and the register configuration is used to switch to the next scan area to be scanned, and scanning is performed according to the partition control method within the next scan area until all scan targets are scanned. Specifically, after determining the scan target, the scanning of the first scan area in the scan target is first performed, and the first scan block in the first scan area is enabled. Within this scan block, the SPAD units are sequentially enabled according to the partition control of the partition mode in the horizontal direction to receive laser light, and the scanning is completed. Subsequently, the register configuration switches to the next scan area, and the SPAD units are sequentially enabled according to the partition control method within each scan block of the next scan area, and the scanning is completed until all scan targets are completed. According to the defined partition method and scan mode, an initial table is configured before starting the SPAD scan. The SPAD units in each scan target are sequentially enabled according to the partition mode to receive laser light, and by dynamically controlling the enabling of the SPAD units, the purpose of suppressing optical crosstalk between SPAD units is achieved.

[0047] The initial table information includes: data representing the enabling status of the SPAD units in the scan area and scan block. Among them, the lower bits of the initial table control the SPAD units on the left, and the higher bits control the SPAD units on the right. In the embodiments of the present application, the SPAD array is divided into 12 Areas in the vertical direction, and each Area corresponds to 192 columns * 12 rows of MPs. Figure 9 For the schematic diagram of the initial table provided by the embodiments of the present application, see Figure 9 The initial table consists of a data table of 192 * 12 bits. Each corresponding bit being 1 indicates that the enabling status of the MP at the corresponding position is on, and the corresponding bit being 0 indicates that the enabling status of the MP at the corresponding position is off. The entire initial table consists of 288 bytes of data. Each row consists of 2 bytes of data. The lower bits control the SPADs on the left, and the higher bits control the SPADs on the right.

[0048] There are two ways to write the initial table. When the scan mode is the general mode or the mobile mode, the initial table is written when the shadow register of the chip is enabled, that is, the configuration of the initial table is completed before starting the ranging.

[0049] In the general mode, the initial table is written to configure the starting position, ending position, and scan order of the SPAD units to be enabled. For example, to fully enable all MPs in each SLOT, all bits in the last two rows of the initial table can be configured as 1. After the configuration is completed, the scanning is automatically performed according to the initial table information according to the defined scan method. Here, the scan order is from bottom to top.

[0050] In the mobile mode, the initial table is written. Since the SPADs to be illuminated at this time are distributed in different rows and columns, it cannot be simply configured by the start and end positions. Configure the row and column numbers of the SPAD units to be enabled through an external communication bus or MCU. It should be noted that if it is necessary to rely on the MCU to intervene to fill in the initial table, in order to save the bus address quantity at this time, the initial table is read and written in the form of a row address plus an offset address. First, the row numbers 0 to 11 need to be configured, and then the 24-byte data of this row is read and written to complete the configuration of the initial table.

[0051] In the mobile mode, configure the initial table information on the host computer according to the scanning requirements. In order to improve the scanning efficiency, two rows are scanned each time, and only the even rows of the actual initial table need to be configured, and the odd rows are automatically the same as the even rows.

[0052] In the ROI mode, configure the ROI area in the initial table. The ROI mode is a sub-mode of the general mode and the mobile mode. If the general mode is selected, the ROI configuration is to change the scanning start and end points in the vertical direction and configure the starting SLOT. For example, configure the starting SLOT as SLOT 0, the scanning start point as the 3rd MP of SLOT 0, and the scanning end point as the 22nd MP of SLOT 0. After completing the configuration of the initial table, the SPADs in the ROI are scanned in the scanning order from bottom to top. If the mobile mode is selected, the ROI area is defined in the initial table. For example, turn on the 3rd, 4th, and 5th column MPs of SLOT 0, the 6th, 7th, and 8th column MPs of SLOT 1, and the 9th, 10th, and 11th column MPs of SLOT 2. After turning on the above areas, keep the number of enabled MP columns unchanged, and increment the SLOT number to complete the mobile mode scanning of one Area.

[0053] In the reverse mobile mode, configure the start position, end position, and reverse scanning order of the SPAD units to be enabled. Here, the reverse scanning order is opposite to the scanning order in the general mode. For example, if the scanning order is from bottom to top, the reverse scanning order is from top to bottom.

[0054] The present invention provides a scanning method for suppressing the SPAD optical crosstalk of a ranging chip. By defining the horizontal partitioning method of the SPAD array, the SPAD units that do not need to be enabled are shielded according to the partitioning method, and the SPAD units that need to be enabled are released. The SPAD array is divided into Areas and SLOTs in the vertical direction, and 4 scanning modes are included for the selection of the scanning mode. According to the defined partitioning mode and the selected scanning mode, configure the initial table before starting the SPAD scanning, and sequentially turn on the SPAD units in each partition to make them receive laser, and achieve the purpose of suppressing the optical crosstalk between SPAD units by dynamically controlling the enabling of the SPAD units.

[0055] The technical features of the above embodiments can be combined arbitrarily. For the sake of concise description, 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, it should be considered as the scope recorded in this specification.

[0056] The above are only the preferred embodiments of the present invention, and are not intended to limit the present invention. Any person skilled in the art can make various changes, modifications, substitutions and variations to these embodiments without departing from the principles and purposes of the present invention. The scope of the present invention is defined by the claims and their equivalents.

Claims

1. A scanning method for suppressing SPAD optical crosstalk of a ranging chip, characterized in that, Including: Determine a partitioning mode according to the pixel points in the horizontal direction of the SPAD array, and perform partitioning control on the SPAD array according to the partitioning mode; Determine the scanning target in the vertical direction of the SPAD array, and configure the scanning mode according to the partitioning mode and the scanning target; Configure an initial table according to the scanning mode, and sequentially turn on the SPAD cells in the scanning target to receive laser according to the initial table information to complete the scanning.

2. The scanning method according to claim 1, characterized in that The partitioning mode includes: The first partitioning mode, in the first partitioning mode, the SPAD array is further configured to include a plurality of large regions, and each large region includes a plurality of small regions; Or, the second partitioning mode.

3. The scanning method according to claim 2, characterized in that, The performing partitioning control on the SPAD array according to the partitioning mode includes In the first partitioning mode, configure a first initial value and a first moving step length for the large regions of the SPAD array, and at the same time configure a second initial value and a second moving step length for the small regions. After cycling through all the large regions according to the trigger signal according to the first initial value and the first moving step length, cycle through the small regions according to the second initial value and the second moving step length; In the second partitioning mode, perform partitioning control through an external selection register.

4. The scanning method according to claim 3, characterized in that, The determining the scanning target in the vertical direction of the SPAD array includes: The SPAD array is further configured into a plurality of scanning regions in the vertical direction, and each scanning region is configured into a plurality of scanning blocks, and the scanning target is selected through a register.

5. The scanning method according to claim 4, characterized in that, Wherein the scanning mode includes at least one of the following: general mode, moving mode, ROI mode, and reverse moving mode.

6. The scanning method according to claim 5, wherein The sequentially turning on the SPAD cells in the scanning target to receive laser according to the initial table information to complete the scanning includes: Sequentially turn on the SPAD cells in each scanning block in the current scanning region for scanning according to the partitioning control method of the current scanning region, and configure the register to switch to the next scanning region to be scanned, and perform scanning according to the partitioning control method in the next scanning region until all scanning targets are scanned.

7. The scanning method according to claim 6, wherein The initial table information includes: data representing the on states of the SPAD cells in the scanning region and the scanning blocks. Among them, the low bits of the initial table control the SPAD cells on the left, and the high bits control the SPAD cells on the right.

8. The scanning method according to claim 7, wherein The configuring the initial table according to the scanning mode includes: In the general mode, configure the starting position, ending position, and scanning order of the SPAD cells to be turned on; In the moving mode, configure the number of rows and columns of the SPAD cells to be turned on through an external communication bus or MCU; In the ROI mode, configure the ROI region in the initial table; In the reverse moving mode, configure the starting position, ending position, and reverse scanning order of the SPAD cells to be turned on.

9. A computer-readable storage medium, characterized in that, A computer program is stored on the computer-readable storage medium, wherein when the computer program is executed by a processor, the scanning method according to any one of claims 1 to 8 is implemented.

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