Circuit board offset correction method, solder paste inspection equipment and storage medium

Abstract

The present application relates to the technical field of circuit board production, and discloses a circuit board offset correction method, solder paste inspection equipment and storage medium. The method divides each preset mark point in a standard file corresponding to the circuit board into a field of view angle area, determines a preset mark point, and determines the field of view angle area corresponding to the preset mark point; moves a camera unit to the field of view angle area corresponding to the preset mark point, and records the first field of view angle coordinates corresponding to the camera unit; obtains a first image of the circuit board and a detection area of ​​the preset mark point; if the preset mark point is identified, records the second field of view angle coordinates corresponding to the camera unit; determines the movement offset of the preset mark point according to the first field of view angle coordinates and the second field of view angle coordinates to correct the entire board coordinates of the circuit board, thereby canceling manual alignment and eliminating the need to shoot the entire page image, so that the position of the standard file matches the position of the circuit board, which can improve the programming efficiency of the detection program.

Description

Technical Field

[0001] The present invention relates to the technical field of circuit board production, and in particular to a circuit board offset correction method, solder paste inspection equipment and a storage medium. Background Art

[0002] About 60-70% of soldering defects in the SMT assembly process of electronic products are caused by poor solder paste printing. During the production process, if there is a problem with the solder paste coating, the components on the finished board are prone to fall off and become defective, or even become unusable. Therefore, it is necessary to check the solder paste coating of the PCB board before mass production.

[0003] Solder Paste Inspection (SPI) refers to the inspection of solder paste height, volume, area, short circuit and offset after printing. Solder paste inspection equipment is a measuring device in patch processing. Solder paste inspection equipment usually uses a black and white camera. When inspecting solder paste, it uses R, G, and B light sources to illuminate separately, obtains images under R, G, and B light sources to synthesize color 2D images.

[0004] At present, when compiling the inspection program, the software system of the solder paste inspection equipment usually first takes a picture of the whole board image of the circuit board, then imports the standard file, sets the marking points in the standard file, and then manually moves the marking points in the standard file so that the marking points in the standard file overlap with the real marking points in the whole board image, sets the binarization threshold of each color channel according to the image of the marking points, simulates the positioning effect of the marking points, and finally saves the compiled inspection program. However, the manual correction method is likely to cause the circuit board to move during printing, resulting in the displacement of the steel mesh and the PCB, the solder paste will be offset after printing, the pad and the steel mesh opening will not match well, and the alignment will be inaccurate, resulting in displacement.

[0005] In addition, when compiling a solder paste inspection program, it is necessary to take a picture of the entire board to provide a reference for manually moving the standard alignment file and the inspection position. When the circuit board to be inspected is large, it takes a long time to take the image of the entire board, which reduces the efficiency of program compilation. Programming time is an important indicator for measuring solder paste equipment. Summary of the invention

[0006] The embodiment of the present application provides a method for correcting the offset of a circuit board, thereby eliminating manual alignment on a full-page image and eliminating the need to shoot the full-page image, so that the position of the standard file matches the position of the circuit board, thereby improving the accuracy of alignment and the programming efficiency of the detection program.

[0007] The embodiments of the present application provide the following technical solutions:

[0008] In a first aspect, an embodiment of the present application provides a circuit board offset correction method, which is applied to a solder paste inspection device, wherein the solder paste inspection device includes a camera unit, and the circuit board offset correction method includes:

[0009] Determine a plurality of viewing angle areas of the camera unit;

[0010] Divide each preset marking point in the standard file corresponding to the circuit board into a field of view angle area;

[0011] Determine a preset marking point, and determine the field of view angle area corresponding to the preset marking point according to the preset marking point;

[0012] Move the camera unit to the field of view angle area corresponding to the preset mark point, and record the first field of view angle coordinates corresponding to the camera unit;

[0013] Acquire a first image of the circuit board and a detection area of ​​a preset marking point;

[0014] Performing a binarization operation on the first image to determine a second image;

[0015] Determine, according to the second image, a detection area image corresponding to the detection area;

[0016] Perform image recognition on the detection area image, and if a preset marking point is recognized, record the second field of view angle coordinates corresponding to the camera unit;

[0017] Determine a movement offset of a preset marking point according to the first field of view angle coordinate and the second field of view angle coordinate;

[0018] Correct the entire board coordinates of the circuit board according to the movement offset of the preset marking point.

[0019] In some embodiments, if the first image includes a second marking point, determining the positioning method of the second marking point is a first positioning method, wherein the first positioning method is used to respond to a first operation on the operation interface to move the second marking point to the detection area;

[0020] If the second marker point is not included in the first image, the positioning method of the marker point is determined to be the second positioning method, wherein the second positioning method is used to respond to a second operation on the operation interface to control the camera unit to shoot in a direction close to the second marker point until the second marker point is included in the first image.

[0021] In some embodiments, acquiring a first image of a circuit board includes:

[0022] Based on a preset first light source mode, acquiring a first image of the circuit board, wherein the first light source mode includes a white balance light source mode;

[0023] The circuit board corresponds to a plurality of light sources. After acquiring a first image of the circuit board, the method further includes:

[0024] Calculate the color of the circuit board, and adjust the parameters of several light sources according to the color of the circuit board to determine the second light source mode, wherein adjusting the parameters of several light sources includes adjusting at least one of the color of the top light source, the brightness of the top light source, the color of the bottom light source, and the brightness of the bottom light source.

[0025] In some embodiments, calculating the color of the circuit board includes:

[0026] Obtain pixel values ​​of all pixels in the first image;

[0027] The pixel values ​​of all pixels are averaged to obtain the average pixel value;

[0028] The color corresponding to the average pixel value is determined as the color of the circuit board.

[0029] In some embodiments, the circuit board corresponds to a plurality of light sources, and after performing image recognition on the detection area image, if a preset marking point is recognized, the method further includes:

[0030] Parameters of the plurality of light sources are adjusted to determine a third light source mode, wherein adjusting the parameters of the plurality of light sources includes adjusting at least one of a color of a top light source, a brightness of a top light source, a color of a bottom light source, and a brightness of a bottom light source.

[0031] In some embodiments, performing image recognition on the detection area image includes:

[0032] Determine the shape recognition similarity of the marker points in the detection area image according to the shape characteristics of the preset marker points;

[0033] According to the shape recognition similarity, it is determined whether there is a preset marking point in the detection area image.

[0034] In some embodiments, performing a binarization operation on the first image to determine the second image includes:

[0035] Obtain a threshold setting instruction, wherein the threshold setting instruction is used to set a binarization threshold;

[0036] The first image is binarized according to a binarization threshold to determine a second image.

[0037] In some embodiments, according to the movement offset of the preset marking point, the whole board coordinates of the circuit board are corrected, including:

[0038] According to the movement offset of the preset marking point, the coordinates of multiple marking points on the circuit board are corrected, and / or the field angle coordinates corresponding to the field angle area are corrected to correct the entire board coordinates of the circuit board.

[0039] In a second aspect, an embodiment of the present application provides a solder paste inspection device, comprising:

[0040] at least one processor; and

[0041] a memory communicatively connected to at least one processor; wherein,

[0042] The memory stores instructions that can be executed by at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the circuit board offset correction method according to the first aspect.

[0043] In a third aspect, an embodiment of the present application provides a non-volatile computer-readable storage medium, which stores computer-executable instructions, and the computer-executable instructions are used to enable a solder paste inspection device to perform a circuit board offset correction method such as the first aspect.

[0044] The beneficial effects of the embodiments of the present application are as follows: Different from the prior art, the embodiments of the present application provide a circuit board offset correction method, the circuit board offset correction method comprising: determining a plurality of field of view angle areas of a camera unit, dividing each preset marking point in a standard file corresponding to the circuit board into a field of view angle area, determining a preset marking point, determining the field of view angle area corresponding to the preset marking point according to the preset marking point, moving the camera unit to the field of view angle area corresponding to the preset marking point, and recording the first field of view angle coordinates corresponding to the camera unit, obtaining a first image of the circuit board and a detection area of ​​the preset marking point; for the first The image is binarized to determine a second image, and a detection area image corresponding to the detection area is determined based on the second image. Image recognition is performed on the detection area image. If a preset mark point is identified, the second field of view angle coordinates corresponding to the camera unit are recorded, and the movement offset of the preset mark point is determined based on the first field of view angle coordinates and the second field of view angle coordinates. According to the movement offset of the preset mark point, the entire board coordinates of the circuit board are corrected. The present application can cancel manual alignment on the entire page image, and there is no need to shoot the entire page image, so that the position of the standard file matches the position of the circuit board, which can improve the accuracy of alignment and the programming efficiency of the detection program. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] One or more embodiments are exemplarily described by corresponding drawings, which do not constitute limitations on the embodiments. Elements with the same reference numerals in the drawings represent similar elements, and the figures in the drawings do not constitute proportional limitations unless otherwise stated.

[0046] Figure 1 is a schematic diagram of an application environment provided by an embodiment of the present application;

[0047] Figure 2 is a schematic diagram of a solder paste inspection preparation process provided by an embodiment of the present application;

[0048] Figure 3 It is a flow chart of a circuit board offset correction method provided in an embodiment of the present application;

[0049] Figure 4 yes Figure 3 A detailed flow chart of step S305 in FIG.

[0050] Figure 5 is a schematic diagram of a process of moving a second marking point to a detection area provided in an embodiment of the present application;

[0051] Figure 6 It is a before-and-after comparison schematic diagram of moving the second marking point to the detection area provided in an embodiment of the present application;

[0052] Figure 7 is a schematic diagram of a process for determining a second light source mode provided in an embodiment of the present application;

[0053] Figure 8 yes Figure 7 A detailed flow chart of step S701 in FIG.

[0054] Fig. 9 is a schematic diagram of a process for determining a third light source mode provided in an embodiment of the present application;

[0055] Fig.10 yes Figure 3 A detailed flow chart of step S306 in FIG.

[0056] Fig.11 This is a schematic diagram comparing the image shooting effects of the detection area under different light sources provided in the embodiment of the present application;

[0057] Fig.12 yes Figure 3 A detailed flow chart of step S308 in FIG.

[0058] Fig.13a This is a schematic diagram of the preview effect of the marked points under different binarization thresholds provided in an embodiment of the present application;

[0059] Fig.13b This is another schematic diagram of the preview effect of the marking point under different binarization thresholds provided in an embodiment of the present application;

[0060] Fig.13c This is another schematic diagram of the preview effect of the marking point under different binarization thresholds provided in the embodiment of the present application;

[0061] Fig.14 yes Figure 3A detailed flowchart of step S310 in FIG.

[0062] Fig.15 It is a schematic diagram of the overall process of a circuit board offset correction method provided in an embodiment of the present application;

[0063] Fig.16 It is a structural schematic diagram of a solder paste inspection device provided in an embodiment of the present application.

[0064] Description of Figure Numbers:

[0065] Label name Label name 100 Application Environment 10 Programmable Logic Controller 20 Control Card 30 Stepper Motor 40 Camera unit 50 light source 120 Solder paste inspection equipment 121 processor 122 Memory DETAILED DESCRIPTION

[0066] In order to facilitate the understanding of the present application, the present application is described in more detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that when an element is described as "fixed to" another element, it can be directly on the other element, or there can be one or more centered elements therebetween. When an element is described as "connected to" another element, it can be directly connected to the other element, or there can be one or more centered elements therebetween. The terms "vertical", "horizontal", "left", "right" and similar expressions used in this specification are for illustrative purposes only.

[0067] Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used in this specification and in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. The term "and / or" used in this specification includes any and all combinations of one or more of the related listed items.

[0068] The technical solution of the present application is described in detail below in conjunction with the accompanying drawings:

[0069] See also Figure 1 , Figure 1 is a schematic diagram of an application environment provided by an embodiment of the present application;

[0070] like Figure 1As shown, the application environment 100 includes: a programmable logic controller (PLC) 10, a control card 20, a stepper motor 30, a camera unit 40 and a light source 50, wherein the programmable logic controller 10 is connected to the control card 20 via network communication, the control card 20 is connected to the stepper motor 30 via network communication, the stepper motor 30 is connected to the camera unit 40 via network communication, and the camera unit 40 is connected to the light source 50 via network communication, wherein the network includes a wired network and / or a wireless network. It is understandable that the network includes wireless networks such as 2G, 3G, 4G, 5G, wireless LAN, Bluetooth, etc., and may also include wired networks such as serial cables and network cables.

[0071] In the embodiment of the present application, the programmable logic controller 10 includes a central processing unit (CPU), a power supply, a storage device, and an input and output interface circuit. The central processing unit is the control center of the programmable logic controller and is also the core component of the programmable logic controller. Its performance determines the performance of the programmable logic controller. The central processing unit is composed of a controller, an arithmetic unit, and a register, and is connected to the input / output interface circuit of the memory through an address bus and a control bus. The central processing unit is arranged in the main body of the programmable logic controller. When performing solder paste detection, the central processing unit is responsible for reading instructions, decoding instructions and executing instructions, processing and running user programs, and performing logical and mathematical operations.

[0072] In the embodiment of the present application, the power supply is used to convert AC power into the DC power required inside the programmable logic controller 10. The internal switching power supply provides DC power to the central processing unit, memory and other circuits of the programmable logic controller 10, so that the programmable logic controller can work normally.

[0073] It can be understood that the power supply includes but is not limited to 220V AC power supply and 24V DC power supply, the DC power supply provided for the central processing unit, memory and other circuits of the programmable logic controller includes but is not limited to 5V, 12V, 24V DC power supply, and the power supply method adopted by the programmable logic controller 10 includes but is not limited to switching regulated power supply.

[0074] In the embodiment of the present application, the memory is a semiconductor circuit with a memory function, and its function is to store system programs, user programs, logic variables and other information. The system program is a program that controls the programmable logic controller to implement various functions, which is written by the manufacturer of the programmable logic controller 10 and fixed in a read-only memory (ROM), which cannot be accessed by the user.

[0075] It can be understood that the memory includes but is not limited to: FLASH flash memory, NAND flash memory, vertical NAND flash memory (VNAND), NOR flash memory, resistive random access memory (RRAM), magnetoresistive random access memory (MRAM), ferroelectric random access memory (FRAM), spin transfer torque random access memory (STT-RAM) and other devices. One or more.

[0076] In the embodiment of the present application, the input and output interface (I / O interface) is a connection circuit for exchanging information between the central processing unit and the external device, and the input and output interface is connected to the central processing unit through a bus. Among them, the input interface is connected to the control card 20, and the output interface is connected to the stepper motor 30. When performing solder paste detection, the control card 20 issues a command, and the command is transmitted to the central processing unit through the input interface. The central processing unit decodes and executes the command, drives the stepper motor 30 through the output interface, and drives the slide rail by the stepper motor 30, and drives the camera unit 40 to move to different positions for shooting.

[0077] The input and output interface (I / O interface) is divided into two categories: bus interface and communication interface. The function of the input and output interface circuit is to input the signals generated by buttons, limit switches or sensors into the central processing unit; the function of the output interface circuit of the programmable logic controller is to convert the signals output by the central processing unit into signals that can drive external actuators, so as to control the on and off of electrical appliances such as contactor coils.

[0078] The computer input and output interface is used for data, information exchange and control between external devices or user circuits and the central processing unit. When in use, the microcomputer bus is used to connect the external devices and user circuits through the microcomputer bus interface.

[0079] The input interface circuit of the programmable logic controller can be divided into a DC input circuit and an AC input circuit. It is understood that the types of output interface circuits include but are not limited to: relay output type, transistor output type and thyristor output type. The output circuits of the relay output type, transistor output type and thyristor output type are similar, except that transistors or thyristors replace relays to control external loads.

[0080] In the embodiment of the present application, the control card 20 is a high-performance stepper motor motion control card based on a computer bus, which uses a high-performance microprocessor and a large-scale programmable device to realize multi-axis coordinated control of multiple stepper motors, including pulse output, pulse counting, digital input, digital output, D / A output and other functions. The control card can send out continuous, high-frequency pulse trains, control the speed of the motor by changing the frequency of the emitted pulses, and control the position of the motor by changing the number of emitted pulses. Its pulse output mode includes pulse / direction and pulse / pulse mode. Pulse counting can be used for position feedback of the encoder, provide the accurate position of the machine, and correct the errors generated during the transmission process. Specifically, the underlying software and hardware for realizing motion control are integrated together, so that it has various speed and position control functions required for stepper motor control, and these functions can be easily called through a computer.

[0081] In the embodiment of the present application, the control card can be a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA), a single-chip microcomputer, an ARM (Acorn RISC Machine) or other programmable logic device, a discrete gate or transistor logic, a discrete hardware component or any combination of these components. The controller can also be any traditional processor, controller, microcontroller or state machine. The controller can also be implemented as a combination of computing devices, for example, a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors combined with a DSP and / or any other such configuration, or a combination of one or more of a microcontroller unit (MCU), a field programmable gate array (FPGA), and a system on chip (SoC).

[0082] In the embodiment of the present application, the stepper motor is an actuator that completes the digital mode conversion, receives the digital control signal (electric pulse signal) and converts it into the corresponding angular displacement or linear displacement. The angular displacement of the stepper motor is strictly proportional to the number of pulses input, and is synchronized with the pulses in time. Therefore, as long as the number of pulses, frequency and phase sequence of the motor windings are controlled, the required angle, speed and direction can be obtained. The stepper motor is an electric motor that converts an electric pulse signal into a corresponding angular displacement or linear displacement. For each input pulse signal, the rotor rotates an angle or moves forward one step, and the output angular displacement or linear displacement is proportional to the number of input pulses, and the speed is proportional to the pulse frequency.

[0083] In the embodiment of the present application, the camera unit 40 is connected to the stepper motor 30, and the stepper motor 30 receives the digital control signal (electric pulse signal) and converts it into an angular displacement or a linear displacement corresponding thereto, drives the slide rail and drives the camera unit to move. The camera unit 40 is used to capture a first image of the circuit board, obtain pixel values ​​of all pixels in the first image, average the pixel values ​​of all pixels to obtain an average pixel value, determine the color corresponding to the average pixel value as the color of the circuit board, and perform a binarization operation on the first image to obtain a second image.

[0084] In the embodiment of the present application, the light source 50 is used for lighting during the shooting process of the camera unit, and the lighting scheme, lighting brightness and lighting angle of the light source can also be adjusted through the control card 20. The number of the light source 50 is multiple, and its types include but are not limited to top red light, bottom red light, bottom green light, and bottom blue light.

[0085] See also Figure 2 , Figure 2 is a schematic diagram of a solder paste inspection preparation process provided by an embodiment of the present application;

[0086] like Figure 2 As shown in the figure, the solder paste inspection preparation process includes:

[0087] Step S201: Create a new solder paste inspection program;

[0088] Specifically, in the solder paste inspection device, a new solder paste inspection program is created to subsequently check whether the marking points in the circuit board are aligned with the preset marking points in the standard file. If not, the offset coordinates are calculated and corrected to the coordinates of the entire circuit board.

[0089] Step S202: importing standard files;

[0090] Specifically, the circuit board graphic data file is read from the database, and then the circuit board is converted into a standard file for output, the output standard file is imported, and the parameters of the standard file are set. When importing the standard file, it is necessary to preliminarily check and confirm the shape, wiring, characters, solder mask and vias in the standard file.

[0091] Step S203: Select and set a preset mark point;

[0092] Specifically, there are several marking points in the standard file, and one of the marking points is randomly selected as the preset marking point.

[0093] Step S204: determining the viewing angle area;

[0094] Specifically, determining the field of view angle area includes two parts: defining the shooting field of view of the camera unit and planning the shooting path of the camera unit; wherein, defining the shooting field of view of the camera unit is to simply iterate according to the known field of view size until all the objects to be measured are divided into the field of view, and then the iteration is terminated; planning the shooting path is to use the TSP algorithm to solve the traveling salesman problem to obtain the shortest path.

[0095] Step S205: placing the circuit board on the track;

[0096] Specifically, according to the size of the circuit board, the circuit board is placed on a track of a corresponding size of the solder paste inspection equipment.

[0097] See also Figure 3 , Figure 3 It is a flow chart of a circuit board offset correction method provided in an embodiment of the present application;

[0098] The circuit board offset correction method is applied to a solder paste inspection device, and the solder paste inspection device includes a camera unit. Specifically, the circuit board offset correction method is executed by one or at least two processors of the solder paste inspection device.

[0099] like Figure 3 As shown, the offset correction method of the circuit board includes:

[0100] Step S301: determining a plurality of viewing angle areas of the camera unit;

[0101] Specifically, a rectangular coordinate system is established with the upper left corner of the circuit board as the coordinate origin. The size of each field of view angle area of ​​the camera unit is set according to the known field of view size of the camera unit, and each field of view angle area is set to have the same length and width. In an embodiment of the present application, the method includes but is not limited to establishing a rectangular coordinate system with the upper left corner, lower left corner, upper right corner, lower right corner, etc. of the circuit board as the origin.

[0102] Step S302: dividing each preset marking point in the standard file corresponding to the circuit board into a field of view angle area;

[0103] Specifically, according to the position of the preset mark point, each preset mark point in the standard file is divided into a field of view angle area that just contains the preset mark point. The remaining preset mark points are simply iterated in this way. During the iteration process, each time the camera unit passes through an iteration, a corresponding field of view angle coordinate is generated at the position of the camera unit until all the preset mark points in the circuit board are divided into a field of view angle area.

[0104] Step S303: determining a preset marking point, and determining a field of view angle area corresponding to the preset marking point according to the preset marking point;

[0105] Specifically, when the solder paste inspection device receives the user's instruction, it selects a preset mark point from several preset mark points in the standard file as the preset mark point for completing the subsequent offset correction operation, and determines the field of view angle area corresponding to the preset mark point based on the location of the preset mark point.

[0106] Step S304: moving the camera unit to the field of view area corresponding to the preset mark point, and recording the first field of view coordinates corresponding to the camera unit;

[0107] Specifically, after determining the field of view angle area corresponding to the preset mark point, the control card sends an instruction to drive the stepper motor, and the stepper motor drives the slide rail to move the camera unit to the field of view angle area corresponding to the preset mark point for shooting, and records the first field of view angle coordinates of the position corresponding to the camera unit at this time, which are used to compare with the second field of view angle coordinates obtained subsequently to obtain the offset coordinates.

[0108] Step S305: Acquire a first image of the circuit board and a detection area of ​​a preset marking point;

[0109] Please refer to Figure 4 , Figure 4 yes Figure 3 A detailed flowchart of step S305 in FIG.

[0110] like Figure 4 As shown, step S305: acquiring a first image of the circuit board includes:

[0111] Step S3051: acquiring a first image of the circuit board based on a preset first light source mode, wherein the first light source mode includes a white balance light source mode;

[0112] Specifically, when performing solder paste inspection, it is necessary to capture the entire board image of the circuit board, and the control card issues a command to adjust the light source mode to a preset first light source mode, and controls the stepper motor to drive the slide rail, so that the camera unit captures the image of the circuit board in the preset first light source mode, thereby obtaining a first image of the circuit. In the embodiment of the present application, the first light source mode includes but is not limited to a white balance light source mode.

[0113] In an embodiment of the present application, the white balance light source can restore the colors in the photo to the colors presented in the real scene. By shooting the circuit board image under the white balance light source mode, the true color of the circuit board itself can be better restored to facilitate subsequent analysis and calculation of the color of the circuit board.

[0114] Please refer to Figure 5 , Figure 5 is a schematic diagram of a process of moving a second marking point to a detection area provided in an embodiment of the present application;

[0115] like Figure 5 As shown, step S501: determining whether the first image includes a second marking point, including:

[0116] Specifically, the camera unit starts to scan and shoot line by line from the origin of the field angle coordinate system, and detects whether the second marking point exists in the first image every time it shoots.

[0117] Step S502: Determine that the positioning method of the marking point is the second positioning method;

[0118] Specifically, if the second marking point does not exist in the first image, the positioning mode of the marking point is determined to be the second positioning mode, and the camera unit is continuously moved to perform line-by-line scanning.

[0119] Step S503: controlling the camera unit to shoot at a position close to the second marking point;

[0120] Specifically, the second positioning mode is used to respond to a second operation on the operation interface. The second positioning mode is used to respond to a second operation on the operation interface. Under the second positioning mode, if there is a second mark point in the first image, the user issues a second operation instruction to control the camera unit to shoot in a direction close to the second mark point until the second mark point is included in the first image, and step S504 is executed.

[0121] Step S504: Determine that the positioning method of the second mark point is the first positioning method;

[0122] Specifically, if there is a second marking point in the captured image, the positioning method of the marking point is determined to be the first positioning method, and the first positioning method is used to respond to the first operation on the operation interface and to move the second marking point to the detection area.

[0123] Please refer to Figure 6 , Figure 6 It is a before-and-after comparison schematic diagram of moving the second marking point to the detection area provided in an embodiment of the present application;

[0124] In the embodiment of the present application, the image before the second marking point is moved is shown in the left figure, and by determining that the positioning method of the marking point is the first positioning method, the second marking point is moved into the detection area as shown in the right figure.

[0125] Please refer to Figure 7 , Figure 7 is a schematic diagram of a process for determining a second light source mode provided in an embodiment of the present application;

[0126] like Figure 7 As shown, determining the second light source mode includes:

[0127] Step S701: Calculate the color of the circuit board;

[0128] In some embodiments, the circuit board corresponds to a plurality of light sources, and after acquiring the first image of the circuit board, the method further includes:

[0129] Calculate the color of the circuit board, and adjust the parameters of several light sources according to the color of the circuit board to determine the second light source mode, wherein adjusting the parameters of several light sources includes adjusting at least one of the color of the top light source, the brightness of the top light source, the color of the bottom light source, and the brightness of the bottom light source.

[0130] Please refer to Figure 8 , Figure 8 yes Figure 7 A detailed flow chart of step S701;

[0131] like Figure 8 As shown, step S701: calculating the color of the circuit board includes:

[0132] Step S7011: Obtain pixel values ​​of all pixels in the first image;

[0133] Specifically, the solder paste inspection device traverses all pixel points in the first image to obtain RGB values ​​of pixel values ​​of all pixel points.

[0134] Step S7012: averaging the pixel values ​​of all pixels to obtain an average pixel value;

[0135] Specifically, the RGB values ​​of all pixels are accumulated to obtain the sum of all pixels, and then the sum of all pixels is divided by the number of all pixels in the first image to finally obtain the average pixel value of the first image.

[0136] Step S7013: Determine the color corresponding to the average pixel value as the color of the circuit board.

[0137] Specifically, according to the calculated average pixel value of the first image, the color corresponding to the average pixel value is determined as the color of the circuit board.

[0138] Step S702: adjusting parameters of several light sources;

[0139] Specifically, according to the color of the circuit board, the parameters of several light sources are adjusted, wherein the light source parameters include: brightness, color combination, position, and angle of the light source. For example, if the color of the circuit board is red, the color combination and brightness of the light source are configured to illuminate red.

[0140] In some embodiments, the light source includes top red light, bottom red light, bottom green light and bottom blue light. By arranging and combining these four light sources, 14 lighting schemes can be obtained.

[0141] Step S703: Determine the second light source mode;

[0142] Specifically, the first light source mode is changed to the second light source mode by adjusting the brightness, color combination, position, and angle of a plurality of light sources, thereby determining the second light source mode.

[0143] In some embodiments, the color combination and brightness scheme of the light source can be preset according to different circuit board colors.

[0144] By calculating the color of the circuit board and adjusting the parameters of several light sources to determine the second light source mode, the problem of unsatisfactory image capture due to diffuse reflection and specular reflection on the circuit board surface can be effectively solved, so that the mark points can be more clearly identified during subsequent offset correction operations.

[0145] Please refer to Fig. 9 , Fig. 9 is a schematic diagram of a process for determining a third light source mode provided in an embodiment of the present application;

[0146] like Fig. 9 As shown, determining the third light source mode includes:

[0147] Step S901: adjusting parameters of several light sources;

[0148] Specifically, based on the second light source mode, if the solder paste inspection equipment still cannot identify the marking point, the third light source mode can be used as needed to adjust the parameters of several light sources, that is, dynamically adjust the brightness, color combination, position, and angle of several light sources.

[0149] Step S902: Determine the third light source mode.

[0150] Specifically, since circuit boards of different colors are set to preset light source schemes in the second light source mode, there may still be a problem of unclear images during the actual shooting process. To address this problem, the solder paste inspection equipment can set the light source mode to a third light source mode. In the third light source mode, the parameters of several light sources can be dynamically adjusted according to shooting needs. The parameters of the light source include brightness, color combination, position, and angle of the light source.

[0151] By adopting the first light source mode to capture the first image of the circuit board, the average pixel value of the circuit board is automatically calculated to obtain the color of the circuit board, and then the second light source mode can be used to execute the corresponding light source scheme according to the color of the circuit board itself. Finally, the third light source mode can be used to dynamically adjust the brightness, color combination, position, and angle of the light source. The present application can avoid the problem of poor shooting effects of circuit boards of different colors caused by the traditional shooting method of using a single light source and a fixed light source position for shooting circuit boards, and improve the accuracy of circuit board offset correction.

[0152] Step S306: performing a binarization operation on the first image to determine a second image;

[0153] Please refer to Fig.10 , Fig.10 yes Figure 3 A detailed flow chart of step S306 in FIG.

[0154] like Fig.10 As shown, step S306: performing a binarization operation on the first image to determine the second image includes:

[0155] Step S3061: Obtain threshold setting instruction;

[0156] Specifically, the solder paste inspection device obtains an instruction from a user to set a binarization threshold.

[0157] Step S3062: setting a binarization threshold;

[0158] Specifically, the solder paste inspection device responds to the user's instruction to set a binarization threshold and sets the binarization threshold, wherein the binarization threshold is between 0 and 255.

[0159] Step S3063: binarizing the first image to determine the second image;

[0160] Specifically, a binarization maximum value is set, wherein the binarization maximum value selects two binarization parameters, a first binarization parameter (THRESH_B I NARY) and a second binarization parameter (THRESH_B I NARY_I NV). The first binarization parameter compares the grayscale value of the pixel with the binarization threshold. If the grayscale value is greater than the threshold, the grayscale value is changed to the binarization maximum value, otherwise the grayscale value is changed to 0. The second binarization parameter is just the opposite. If the grayscale value is greater than the binarization threshold, the grayscale value is changed to 0, otherwise the grayscale value is changed to the maximum binarization value, thereby realizing binarization and presenting the entire image with an obvious visual effect of only black and white to determine the second image.

[0161] The present application binarizes the first image to present the entire image with an obvious visual effect of only black and white, so that the marking points can be more clearly identified in the subsequent offset correction operation of the circuit board.

[0162] Step S307: determining a detection area image corresponding to the detection area according to the second image;

[0163] Specifically, after obtaining the binarized second image, the control card sends a command to drive the stepper motor, and the stepper motor drives the slide rail to move the camera unit to the detection area in the second image for shooting, and obtain the detection area image corresponding to the detection area.

[0164] Please refer to Fig.11 , Fig.11 This is a schematic diagram comparing the image shooting effects of the detection area under different light sources provided in the embodiment of the present application;

[0165] It can be seen that Fig.11 As shown in part A of FIG, under the top red light source, the shape of the second mark point in the detection area image is visible but not clear enough, and the difference between the mark point and the circuit board is not obvious enough; Fig.11 As shown in part B of FIG, under the bottom green light source, the black and white color difference between the second mark point in the detection area image and the circuit board is not significant, and the difference is not obvious, making it difficult to find the specific position of the mark point; Fig.11 As shown in part C of FIG, under the bottom blue light source, the black and white color difference between the second mark point in the detection area image and the circuit board is very small and the difference is not obvious, so it is difficult to find the specific position of the mark point; Fig.11 In the D part, under the combined light source of red, green and blue, the second marking point in the detection area image can be clearly identified, and the difference between the second marking point and the circuit board is most obvious under this light source.

[0166] Step S308: performing image recognition on the detection area image, and if a preset marking point is recognized, recording the second field angle coordinates corresponding to the camera unit;

[0167] Please refer to Fig.12 , Fig.12 yes Figure 3 A detailed flow chart of step S308 in FIG.

[0168] like Fig.12 As shown, step S308: performing image recognition on the detection area image includes:

[0169] Step S3081: determining the shape recognition similarity of the marking points in the detection area image;

[0170] Specifically, according to the shape characteristics of the marking point, the solder paste inspection device uses the Opencv image recognition algorithm to identify the shape of the marking point. The algorithm uses contour approximation to identify the shape. Contour approximation is based on the assumption that a curve can be approximated by a series of short line segments. The perimeter of the shape contour is calculated to obtain the shape contour characteristics of the marking point. According to the shape contour characteristics of the marking point, different shape contour characteristics are preset with different shape recognition similarities. The user issues an instruction to set the shape recognition similarity of the marking point. For example, if the shape contour feature of the marking point is a circle, the roundness is used to measure the shape recognition similarity.

[0171] Please refer to FIG. 13 again, which is a schematic diagram comparing the preview effects of marked points under different binarization thresholds provided in an embodiment of the present application;

[0172] It can be seen that in Fig.13a In the example, when the binarization threshold is set to 38 and the shape recognition similarity is set to 30, the shape of the second mark cannot be recognized at all and the recognition effect is poor.

[0173] exist Fig.13b In the example, when the binarization threshold is set to 68 and the shape recognition similarity is set to 30, the solder paste inspection device recognizes two elliptical points, but still fails to accurately recognize the second marking point.

[0174] exist Fig.13c In the figure, when the binarization threshold is set to 85 and the shape recognition similarity is set to 30, the solder paste inspection equipment successfully recognizes the second marking point, and the recognition effect is good.

[0175] Step S3082: Determine whether there is a preset marking point in the detection area image;

[0176] Specifically, after setting the shape recognition similarity, the detection area image is identified to determine whether there are preset marking points in the detection area image. If it is identified that there are preset marking points in the detection area image, the second field of view angle coordinates corresponding to the position of the camera unit at this time are recorded; if it is identified that there are no preset marking points in the detection area image, the third light source mode is re-entered, the parameters of several light sources are adjusted, and then steps S306, S307, and S308 are repeated until the preset marking points in the detection area image can be identified.

[0177] Step S309: determining a movement offset of a preset marking point according to the first field of view angle coordinate and the second field of view angle coordinate;

[0178] Specifically, according to the first field of view angle coordinates and the second field of view angle coordinates of the camera unit, the movement offset between the first field of view angle coordinates and the second field of view angle coordinates is automatically calculated. Assuming that the first field of view angle coordinates are (x1, y1) and the second field of view angle coordinates are (x2, y2), the calculation formula for the movement offset is (offset_x, offset_y) = (x2-x1, y2-y1).

[0179] Step S310: Correcting the entire board coordinates of the circuit board according to the movement offset of the preset marking point;

[0180] Please refer to Fig.14 , Fig.14 yes Figure 3 A detailed flowchart of step S310 in FIG.

[0181] like Fig.14As shown, step S310: correcting the entire page coordinates of the circuit board according to the movement offset of the preset marking point, including:

[0182] Step S3101: calibrating the coordinates of a plurality of marking points on the circuit board, and / or calibrating the viewing angle coordinates corresponding to the viewing angle area;

[0183] Specifically, the entire board coordinates of the circuit board include the coordinates of all marking points on the circuit board and the coordinates of all field angles. Assuming that the coordinates of another marking point are (x3, y3), the corrected coordinates of the marking point are (x3', y3'). The specific calculation formula is as follows:

[0184] x3'=x3+offset_x,

[0185] y3'=y3+offset_y;

[0186] In an embodiment of the present application, by calculating the movement offset of the first field of view angle coordinate and the second field of view angle coordinate, and correcting the movement offset to the coordinates of all marking points on the circuit board and all field of view angle coordinates, the time of traditional manual alignment can be effectively saved, and the circuit board offset correction can be achieved without taking a picture of the entire circuit board image, thereby improving the efficiency of the circuit board offset correction.

[0187] See also Fig.15 , Fig.15 It is a schematic diagram of the overall process of a circuit board offset correction method provided in an embodiment of the present application;

[0188] Step S1501: Create a new solder paste inspection program;

[0189] Step S1502: importing standard files;

[0190] Step S1503: determining a preset marking point;

[0191] Step S1504: determining whether the preset marking point has been determined;

[0192] Specifically, before determining the field of view angle area, the solder paste inspection device will automatically detect whether a preset mark point has been selected as the mark point for subsequent calibration. If the solder paste inspection device detects that the preset mark point has been determined, it will automatically enter the field of view angle area determination page. If the device detects that the preset mark point has not been determined, it will return to step S1503 and perform detection after determining a preset mark point.

[0193] Step S1505: Determine the field of view angle area;

[0194] Step S1506: determining whether the viewing angle area has been determined;

[0195] Specifically, before determining the track number and placing the circuit board into the corresponding track, the solder paste inspection device will automatically detect whether the field of view angle area has been determined. If the solder paste inspection device detects that the field of view angle area has been determined, it will automatically enter the track number determination page; if the solder paste inspection device detects that the field of view angle area has not been determined, it will return to step S1505 and perform detection after the field of view angle area is determined;

[0196] Step S1507: Determine whether it is a dual-track model;

[0197] Specifically, before placing the circuit board on the track, in order to be compatible with single-track and dual-track models, the solder paste inspection equipment will automatically determine the equipment track number. If it is a single-track model, the circuit board will be directly placed on the track.

[0198] Step S1508: placing the circuit board on the track;

[0199] Step S1509: Select the track number;

[0200] Specifically, if it is a dual-track model, the solder paste detection equipment will prompt the user to select a track number, the user issues an instruction, selects a track number, and then places the circuit board on the track corresponding to the track number.

[0201] Step S1510: moving the camera unit to a field of view area corresponding to a preset mark point;

[0202] Step S1511: Acquire a first image of a circuit board;

[0203] Step S1512: determining whether the first image contains a preset marking point;

[0204] Step S1513: recording the first field angle coordinates corresponding to the camera unit;

[0205] Step S1514: Check the light source and brightness value of different channels;

[0206] Step S1515: setting a binarization threshold to determine a second image;

[0207] Step S1516: Determine whether the preset marking point can be identified;

[0208] Step S1517: recording the coordinates of the second field of view angle corresponding to the camera unit, and calculating the movement offset;

[0209] Step S1518: Save the moving offset, light source parameters, binarization threshold parameters, and shape similarity of the marker point;

[0210] Specifically, after the movement offset is calculated based on the first field of view angle coordinates and the second field of view angle coordinates, the solder paste inspection equipment will not only automatically save the movement offset, but also automatically save the light source parameters, binarization threshold parameters, and shape similarity parameters of the marking points finally determined in the entire circuit board offset correction process, among which the light source parameters include: brightness, color combination, position, and angle of the light source, so that when the standard file is subsequently applied to the offset correction of other circuit boards, the parameters can be directly selected as a reference.

[0211] Step S1519: calibrating the entire board coordinates of the circuit board;

[0212] Among them, steps S1501, S1502, S1503, S1505, S1508, S1510, S1511, S1512, S1513, S1514, S1515, S1516, S1517, and S1519 have been described in detail in the above embodiments. To avoid repetition, they will not be described in detail here. Please refer to the relevant contents in the above embodiments for details.

[0213] Please refer to Fig.16 , Fig.16 It is a structural schematic diagram of a solder paste inspection device provided in an embodiment of the present application;

[0214] like Fig.16 As shown, the solder paste inspection device 160 includes one or more processors 161 and a memory 162. Fig.16 A processor 161 is taken as an example.

[0215] The processor 161 and the memory 162 may be connected via a bus or other means. Fig.16 The example of connecting through bus is taken in the following.

[0216] The processor 161 is used to provide computing and control capabilities to control the solder paste inspection device 160 to perform corresponding tasks, for example, to control the solder paste inspection device 160 to perform the offset correction method of the circuit board in any of the above-mentioned method embodiments, including: determining a plurality of field of view angle areas of the camera unit, and dividing each preset mark point in the standard file corresponding to the circuit board into a field of view angle area; determining a preset mark point, and determining the field of view angle area corresponding to the preset mark point according to the preset mark point; moving the camera unit to the field of view angle area corresponding to the preset mark point, and recording the first field of view angle coordinate corresponding to the camera unit; acquiring a first image of the circuit board and a detection area of ​​the preset mark point; performing a binarization operation on the first image to determine a second image; determining a detection area image corresponding to the detection area according to the second image; performing image recognition on the detection area image, and if the preset mark point is recognized, recording the second field of view angle coordinate corresponding to the camera unit; determining the movement offset of the preset mark point according to the first field of view angle coordinate and the second field of view angle coordinate; and correcting the entire board coordinates of the circuit board according to the movement offset of the preset mark point.

[0217] The movement offset of the preset marking point is determined by the first field of view angle coordinates and the second field of view angle coordinates to correct the entire board coordinates of the circuit board, thereby eliminating manual alignment and eliminating the need to take a full-page image, so that the position of the standard file matches the position of the circuit board, which can improve the programming efficiency of the detection program.

[0218] The processor 161 may be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), a hardware chip or any combination thereof; it may also be a digital signal processor (DSP), an application specific integrated circuit (ASIC), a programmable logic device (PLD) or a combination thereof. The above-mentioned PLD may be a complex programmable logic device (CPLD), a field programmable gate array (FPGA), a general array logic (GAL) or any combination thereof.

[0219] The memory 162 is a non-transitory computer-readable storage medium, which can be used to store non-transitory software programs, non-transitory computer executable programs and modules, such as program instructions / modules corresponding to the offset correction method of the circuit board in the embodiment of the present application. The processor 161 can implement the offset correction method of the circuit board in any of the following method embodiments by running the non-transitory software programs, instructions and modules stored in the memory 162. Specifically, the memory 162 may include a volatile memory (VM), such as a random access memory (RAM); the memory 162 may also include a non-volatile memory (NVM), such as a read-only memory (ROM), a flash memory, a hard disk (HDD) or a solid-state drive (SSD) or other non-transitory solid-state storage device; the memory 162 may also include a combination of the above-mentioned types of memory.

[0220] The memory 162 may include a high-speed random access memory, and may also include a non-volatile memory, such as at least one disk storage device, a flash memory device, or other non-volatile solid-state storage devices. In some embodiments, the memory 162 may optionally include a memory remotely arranged relative to the processor 161, and these remote memories may be connected to the processor 161 via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0221] One or more modules are stored in the memory 162, and when executed by one or more processors 161, the circuit board offset correction method in any of the above method embodiments is executed, for example, the above described method is executed. Figure 3 The steps shown.

[0222] In the embodiment of the present application, the solder paste inspection device 160 may also have components such as a wired or wireless network interface, a keyboard, and an input and output interface for input and output. The solder paste inspection device 160 may also include other components for realizing the functions of the device, which will not be repeated here.

[0223] The present application also provides a computer-readable storage medium, such as a memory including a program code, and the program code can be executed by a processor to complete the circuit board offset correction method in the above embodiment. For example, the computer-readable storage medium can be a read-only memory (ROM), a random access memory (RAM), a compact disc (CDROM), a magnetic tape, a floppy disk, and an optical data storage device.

[0224] The embodiment of the present application also provides a computer program product, which includes one or more program codes, and the program code is stored in a computer-readable storage medium. The processor of the electronic device reads the program code from the computer-readable storage medium, and the processor executes the program code to complete the method steps of the offset correction method of the circuit board provided in the above embodiment.

[0225] A person skilled in the art will appreciate that all or part of the steps for implementing the above embodiments may be accomplished by hardware or by hardware associated with a program code, and the program may be stored in a computer-readable storage medium, and the above-mentioned storage medium may be a read-only memory, a disk or an optical disk, etc.

[0226] Through the description of the above implementation methods, ordinary technicians in this field can clearly understand that each implementation method can be implemented by means of software plus a general hardware platform, and of course, it can also be implemented by hardware. Ordinary technicians in this field can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing related hardware through a computer program, and the program can be stored in a computer-readable storage medium. When the program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, the storage medium can be a disk, an optical disk, a read-only memory (ROM) or a random access memory (RAM), etc.

[0227] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Under the concept of the present application, the technical features in the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other changes in different aspects of the present application as mentioned above, which are not provided in detail for the sake of simplicity. Although the present application has been described in detail with reference to the aforementioned embodiments, a person of ordinary skill in the art should understand that the technical solutions described in the aforementioned embodiments can still be modified, or some of the technical features can be replaced by equivalents. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A circuit board offset correction method, characterized in that: Applied to a solder paste inspection device, the solder paste inspection device includes a camera unit, and the method includes: Determining a plurality of viewing angle areas of the camera unit; Divide each preset marking point in the standard file corresponding to the circuit board into a field of view angle area; Determine a preset marking point, and determine the field of view angle area corresponding to the preset marking point according to the preset marking point; Moving the camera unit to the field of view angle area corresponding to the preset mark point, and recording the first field of view angle coordinates corresponding to the camera unit; Acquire a first image of the circuit board and a detection area of ​​the preset marking point; Performing a binarization operation on the first image to determine a second image; determining, according to the second image, a detection area image corresponding to the detection area; Performing image recognition on the detection area image, and if the preset marking point is recognized, recording the second field of view angle coordinates corresponding to the camera unit; Determining a movement offset of the preset marking point according to the first field of view angle coordinates and the second field of view angle coordinates; The entire board coordinates of the circuit board are corrected according to the movement offset of the preset marking point.

2. The method according to claim 1, characterized in that The method further comprises: If the first image includes a second marking point, determining that the positioning method of the second marking point is a first positioning method, wherein the first positioning method is used to respond to a first operation on the operation interface to move the second marking point to the detection area; If the second marker point is not included in the first image, the positioning method of the marker point is determined to be the second positioning method, wherein the second positioning method is used to respond to a second operation on the operation interface to control the camera unit to shoot in a direction close to the second marker point until the second marker point is included in the first image.

3. The method according to claim 1 or 2, characterized in that: The acquiring a first image of the circuit board comprises: Based on a preset first light source mode, acquiring a first image of the circuit board, wherein the first light source mode includes a white balance light source mode; The circuit board corresponds to a plurality of light sources. After acquiring a first image of the circuit board, the method further includes: Calculate the color of the circuit board, and adjust the parameters of several of the light sources according to the color of the circuit board to determine a second light source mode, wherein adjusting the parameters of several of the light sources includes adjusting at least one of the color of the top light source, the brightness of the top light source, the color of the bottom light source, and the brightness of the bottom light source.

4. The method according to claim 3, characterized in that The calculating the color of the circuit board comprises: Obtain pixel values ​​of all pixels in the first image; The pixel values ​​of all pixels are averaged to obtain the average pixel value; The color corresponding to the average pixel value is determined as the color of the circuit board.

5. The method according to any one of claims 1, 2 and 4, characterized in that: The circuit board corresponds to a plurality of light sources. After performing image recognition on the detection area image, if the preset marking point is recognized, the method further includes: Parameters of the plurality of light sources are adjusted to determine a third light source mode, wherein adjusting the parameters of the plurality of light sources comprises adjusting at least one of a color of a top light source, a brightness of a top light source, a color of a bottom light source, and a brightness of a bottom light source.

6. The method according to any one of claims 1, 2 and 4, characterized in that: The performing image recognition on the detection area image includes: Determining shape recognition similarity of the marker points in the detection area image according to shape features of the preset marker points; It is determined whether the preset marking point exists in the detection area image according to the shape recognition similarity.

7. The method according to any one of claims 1, 2 and 4, characterized in that: The performing a binarization operation on the first image to determine the second image includes: Obtaining a threshold setting instruction, wherein the threshold setting instruction is used to set a binarization threshold; The first image is binarized according to the binarization threshold to determine the second image.

8. The method according to any one of claims 1, 2 and 4, characterized in that: The step of correcting the entire board coordinates of the circuit board according to the movement offset of the preset marking point comprises: According to the movement offset of the preset marking point, the coordinates of multiple marking points on the circuit board are corrected, and / or the field of view angle coordinates corresponding to the field of view angle area are corrected to correct the entire board coordinates of the circuit board.

9. A solder paste inspection device, characterized in that: include: 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 offset correction method for the circuit board as described in any one of claims 1-8.

10. A non-volatile computer-readable storage medium, characterized in that: The non-volatile computer-readable storage medium stores computer-executable instructions, and the computer-executable instructions are used to enable the solder paste inspection device to execute the circuit board offset correction method as described in any one of claims 1-8.

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