High-precision data line and production method thereof

Abstract

According to the high-precision data line and the production method thereof disclosed by the invention, an insulating base and an insulating body are designed in a split manner, so that the influence of a guide groove on machine vision image detection can be effectively avoided, the machine vision image detection of a welding spot structure is clearer and more complete, and meanwhile, the data acquisition amount is larger; the efficiency of the data line interface welding spots in the machine vision detection process is greatly improved, meanwhile, the data processing error is reduced, the detection image is obtained through image capturing in multiple different directions, the target welding spot set is detected from multiple dimensions, the data size is richer, the processing speed is higher, and the detection accuracy is higher. The thermal imaging images of the target welding spot group at different time points and different angles can be captured through the thermal infrared imager, so that the operation condition of the welding spot group can be better tracked and analyzed, better data analysis can be performed on the target welding spot group, the detection of the target welding spot group is more accurate, and the detection efficiency is improved. And the yield and the efficiency of data line production are higher.

Description

Technical Field

[0001] The present invention relates to the technical field of data line production, in particular to a high-precision data line and a production method thereof. Background Art

[0002] As stated in the published patent "A data line interface automatic detection method based on machine vision" (paragraphs 0002-0003 of the specification) with the announcement number CN114594102B, machine vision technology is an interdisciplinary subject involving artificial intelligence, neurobiology, psychophysics, computer science, image processing, pattern recognition and many other fields. Machine vision mainly uses computers to simulate human visual functions, extract information from the images of objective objects, process and understand them, and finally use them for actual detection, measurement and control.

[0003] In the existing production lines, for the inspection of data cable interfaces, machines can only inspect the performance of data cable interfaces, while for the appearance problems of data cable interfaces such as wear, missing, discoloration, etc., they can only rely on manual inspection. How to use visual inspection technology to improve the inspection efficiency of data cable interfaces is a problem we need to solve. Now we provide an automatic inspection method for data cable interfaces based on machine vision.

[0004] As described in the published patent "A cable joint solder joint qualification detection method based on deep learning technology" (paragraphs 0002-0003 of the specification) with publication number CN110570398A, during the welding process of electronic products, defects in solder joints may occur due to equipment errors, manual operation errors, etc., such as bridging, cold soldering, leaking solder joints, wrong PINs, excessive PVC shrinkage, damaged core wire sheaths, and missed cutting of braided wires. If such defective data cables are applied to electronic products, it will directly affect the life and stability of the electronic products, and may even cause the entire electronic product to be scrapped. Therefore, the quality of the solder joints directly affects the quality of the data cables. At present, solder joint defect inspection is still completed by manual visual inspection, which is inefficient and inaccurate.

[0005] The existing methods for testing the quality of cable joint welding include resistance measurement method, voltage drop detection method, X-ray detection method, eddy current detection method, etc. Among them, the resistance measurement method and the voltage drop detection method both use electrical parameters to determine the quality of the solder joint. The method is simple, but the electrical parameters are too insensitive to the internal defect type of the solder joint, so the accuracy of the solder joint quality determination result is not high; the X-ray detection method is simple to operate, the radiographic information of the solder joint is clear and easy to identify, and can accurately read the diameter of the solder joint nugget and the internal defects, but X-rays have radioactive hazards and require high on-site operating environments, making it difficult to apply in industrial production; the eddy current detection method has the problem of missing defects in the solder joint, and the missed detection rate is high, so it cannot be applied in industrial production. These traditional detection methods do not use the subtle features of the solder joint, and cannot determine whether the solder joint is qualified and the classification of unqualified solder joints. Some solder joints with minor defects cannot be accurately detected, the misjudgment rate is high, the calculation complexity is large, and the scalability is poor, which cannot meet the needs of modern production.

[0006] In summary, in the existing data cable processing, there are problems of low efficiency and large errors in the quality inspection of the data cable interface solder joints. Summary of the invention

[0007] In order to overcome the above-mentioned shortcomings, the present invention aims to provide a technical solution that can solve the above-mentioned problems.

[0008] To achieve the above object, the present invention provides the following technical solutions: A high-precision data line and a production method thereof, comprising a line body and data line connectors respectively connected to both ends of the line body, wherein the data line connector comprises a shielding shell and an insulating body arranged in the shielding shell; A mounting groove penetrating the front and rear end surfaces is provided in the middle of the front end of the insulating body, and a plurality of upper terminal grooves and lower terminal grooves evenly spaced are respectively provided on the upper and lower inner walls of the mounting groove, and an upper plug hole and a lower plug hole communicating with the rear end of the insulating body are respectively provided on the rear inner walls of the upper terminal groove and the lower terminal groove; The upper terminal groove and the lower terminal groove are respectively inserted with an upper conductive terminal and a lower conductive terminal, and the upper conductive terminal and the lower conductive terminal extend out of the rear end of the insulating body from the upper plug hole and the lower plug hole respectively; An insulating base is provided between the upper conductive terminal and the lower conductive terminal and is plugged into the mounting groove. The upper and lower end surfaces of the insulating base are respectively provided with guide grooves for mounting the upper conductive terminal and the lower conductive terminal. Ground terminals are respectively extended backwards on both sides of the shielding shell. A method for producing a high-precision data line comprises the following steps: S100: After temporarily sealing the rear end of the installation groove of the insulating body, an optical microscope camera is used to collect images of the target welding point group from the target detection direction; S200: The image acquisition of the target welding point group includes at least a first target detection direction and a second target detection direction, respectively acquiring a first detection image and a second detection image from the first target detection direction and the second target detection direction, and performing graphic detection after grayscale and binarization processing on the first detection image and the second detection image; S300: Connect the target data line to the rated working circuit, and the infrared thermal imager obtains the first thermal imaging image group and the second thermal imaging image group of the target solder joint group from the first target detection direction and the second target detection direction respectively based on the increasing time points, and tracks and detects the first thermal imaging image group and the second thermal imaging image group.

[0009] As a further solution of the present invention: the step S100 includes the following operation steps; S110: The intersection of the plane where the upper boundary and the lower boundary of the field of view in the target detection direction are located and the rear end surface of the insulating body is within a first interval, and the first interval includes the area between the vertical projections of the upper end surface of the insulating body and the upper end surface of the lower conductive terminal on the rear end surface of the insulating body.

[0010] As a further solution of the present invention: the step S100 includes the following operation steps; S120: The intersection of the plane where the left boundary and the right boundary of the field of view in the target detection direction are located and the rear end surface of the insulating body is within a second interval, and the second interval includes the area between the leftmost end and the rightmost end of the insulating body; S130: The left boundary and the right boundary of the field of view in the target detection direction exceed the rear end of the ground terminal.

[0011] As a further solution of the present invention, step S200 includes the following steps: S210: The first target detection direction and the second target detection direction are respectively perpendicular to a first reference line, and the first reference line is perpendicular to a left end surface of an upper conductive terminal.

[0012] As a further solution of the present invention, step S210 includes the following steps: S211: Acquisition of the first detection image includes the following steps; The front boundary of the field of view in the first target detection direction exceeds the front end of the target welding point group, and the rear boundary of the field of view in the first target detection direction exceeds the rear end of the target welding point group; S212: The graphic detection of the first detection image comprises the following steps; In the first detection image, for any connected domain, the respective edge lines are closed to obtain n closed domains S11, S12, ..., S1n. For any closed domain, the front end or the rear end of the edge line is taken as the initial point, and the distances between the left and right pixel points of the edge line of the closed domain are obtained in sequence along the front-to-back direction, and are recorded and stored in sequence as the first width array L11, L12, ..., L1n; The sequence number where the median of L11, L12, ..., L1n is located is recorded as the mark sequence number, and the sequence number where the maximum value of L11, L12, ..., L1n is located is recorded as the target sequence number. The next step is performed if and only if the difference between the mark sequence number and the target sequence number is within a threshold range, and the threshold is less than 1 / 5 of the number of elements in the first width array; Determine whether the difference signs of the previous element and the next element in the range from L11 to the target sequence number are the same, and determine whether the difference signs of the previous element and the next element in the range from the target sequence number to L1n are the same. If the above conditions are met, proceed to the next step; If and only if the differences of adjacent elements are all within the threshold range, the solder joint detection corresponding to the closed domain is qualified; Compare the distance between the front and rear ends of the edge line with the standard value.

[0013] As a further solution of the present invention, step S210 includes the following steps: S215: Acquisition of the second detection image includes the following steps; The upper boundary of the field of view in the second target detection direction exceeds the upper end of the target welding point group, and the lower boundary of the field of view in the second target detection direction exceeds the lower end of the target welding point group; S216: The graphic detection of the second detection image includes the following steps: In the second detection image, for any connected domain, the respective edge lines are closed to obtain n closed domains S21, S22, ..., S2n. For any closed domain, the upper end of the edge line is taken as the initial point, and the distances between the left and right pixel points of the edge line of the closed domain are obtained in sequence along the vertical direction, and are recorded and stored in sequence as the second width array L21, L22, ..., L2n; The difference between the next element and the previous element in L21, L22, ..., L2n is judged in sequence. In any closed domain, when the differences between adjacent elements are all positive numbers and within the threshold range, the solder joint detection corresponding to the closed domain is qualified; Compare the distance between the upper and lower ends of the edge line with the standard value.

[0014] As a further solution of the present invention: in step S210, the graphic detection of the second detection image further includes the following steps: S217: In the second detection graph, for any connected domain, the respective edge lines are closed to obtain n closed domains S21, S22, ..., S2n. For any closed domain, the upper end of the edge line is used as the initial point, and the shortest distances between the edge lines of adjacent closed domains are obtained in sequence along the vertical direction, and are recorded and stored as third width arrays L31, L32, ..., L3n respectively. Compare L31, L32, ..., L3n with the standard values ​​respectively.

[0015] As a further solution of the present invention: Step S300 includes the following steps: S310: Acquisition of the first thermal imaging image group includes the following steps: A first time group consisting of a plurality of incremental time points t11, t12, ..., t1n is preset, Based on the time points in the first time group t11, t12, ..., t1n, respectively, a plurality of thermal images P11, P12, ..., P1n are acquired from the first target detection direction; S320: The tracking detection of the first thermal imaging image group includes the following steps: The thermal imaging images P11, P12, ..., P1n are respectively matched and compared with the first detection image, and the thermal imaging points of the thermal imaging images P11, P12, ..., P1n are respectively marked in the closed domains S11, S12, ..., S1n. For any closed domain, if and only if the thermal imaging points in the closed domain are uniformly progressive from the edge line to the middle, proceed to the next step; For any closed domain, the superimposed area of ​​the thermal imaging points on the thermal imaging images P11, P12, ..., P1n within the closed domain coincides with the edge line.

[0016] As a further solution of the present invention: Step S300 includes the following steps: S330: Acquisition of the second thermal imaging image group includes the following steps: A first time group consisting of a plurality of incremental time points t11, t12, ..., t1n is preset, Based on the time points in the first time group t11, t12, ..., t1n, respectively, a plurality of thermal images P21, P22, ..., P2n are acquired from the second target detection direction; S340: The tracking detection of the second thermal imaging image group includes the following steps: The thermal images P21, P22, ..., P2n are respectively matched and compared with the second detection image, and the thermal imaging points of the thermal images P21, P22, ..., P2n are respectively marked in the closed domains S21, S22, ..., S2n. For any closed domain, if and only if the thermal imaging points in the closed domain are uniformly progressive from the middle to both sides, proceed to the next step; For any closed domain, the superimposed area of ​​the thermal imaging points on the thermal imaging images P11, P12, ..., P1n within the closed domain coincides with the edge line.

[0017] Compared with the prior art, the present invention has the following beneficial effects: 1. By designing the insulating base and the insulating body separately, the influence of the guide groove on the machine vision image detection can be effectively avoided, making the machine vision image detection of the solder joint structure clearer and more complete, while the data collection volume is larger, greatly improving the efficiency of the data line interface solder joint in the machine vision detection process, and reducing the error of data processing.

[0018] 2. In the present invention, the detection image is obtained by capturing images in multiple different directions, and the target solder joint group is detected from multiple dimensions, so that the detection accuracy is higher, the data volume is richer, and the processing speed is faster. The infrared thermal imager can capture the thermal imaging images of the target solder joint group at different time points and different angles, so that the operation status of the solder joint group can be better tracked and analyzed, so that the target solder joint group can be better analyzed. The detection of the target solder joint group is more accurate, the yield rate of data cable production is higher, and the production efficiency is higher. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a three-dimensional structural diagram of a data line connector in the prior art; Figure 2 is a three-dimensional structural diagram of a data line connector in an embodiment of the present invention; Figure 3 is a cross-sectional view of a data line connector in an embodiment of the present invention; Figure 4 is a left side view of a data line connector in one embodiment of the present invention; Figure 5 is a front view of a data line connector in one embodiment of the present invention; Figure 6 is a top view of a data line connector in one embodiment of the present invention; Figure 7 is another three-dimensional structural diagram of a data line connector in one embodiment of the present invention; Figure 8 is a structural stereogram of a target solder joint in an embodiment of the present invention; Fig. 9 is another structural stereogram of a target welding spot in one embodiment of the present invention; Fig.10 is a top view of a target solder joint in one embodiment of the present invention; Fig.11 is a front view of a target solder joint in one embodiment of the present invention; Fig.12 is a front view of a data line connector with a target solder joint group in one embodiment of the present invention; Fig.13 yes Fig.10 The cross section along the DD direction; Fig.14 is a flow chart of steps 100-300 in the present invention; Fig.15 is a flow chart of steps 100, 120-130 of the present invention; Fig.16 is a flow chart of steps 211-212, 215-216 in the present invention; Fig.17 It is the flow chart of 310-320 / 330-340 in the present invention; Data line connector 100, shielding shell 110, insulating body 120, mounting groove 121, upper terminal groove 122, lower terminal groove 123, upper plug hole 124, lower plug hole 125, upper conductive terminal 130, lower conductive terminal 140, insulating base 150, guide groove 151, grounding terminal 160. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0021] See also Figure 1-17 A high-precision data line includes a line body and a data line connector 100 respectively connected to both ends of the line body, wherein the data line connector 100 includes a shielding shell 110 and an insulating body 120 disposed in the shielding shell; A mounting groove 121 penetrating the front and rear end surfaces is provided in the middle of the front end of the insulating body, and a plurality of upper terminal grooves 122 and lower terminal grooves 123 evenly spaced are provided on the upper and lower inner walls of the mounting groove, and an upper plug hole 124 and a lower plug hole 125 communicating with the rear end of the insulating body are provided on the rear inner walls of the upper terminal groove 122 and the lower terminal groove 123, respectively. The upper terminal groove and the lower terminal groove are respectively inserted with an upper conductive terminal 130 and a lower conductive terminal 140, and the upper conductive terminal and the lower conductive terminal extend out of the rear end of the insulating body from the upper plug hole and the lower plug hole respectively; An insulating base 150 is provided between the upper conductive terminal and the lower conductive terminal and is plugged into the mounting groove. The upper and lower end surfaces of the insulating base 150 are respectively provided with guide grooves 151 for mounting the upper conductive terminal 130 and the lower conductive terminal 140. Ground terminals 160 are respectively extended backwards on both sides of the shielding shell; like Figure 1 and Figure 2 As shown, for some data lines for specific purposes, especially high-precision data lines, their data line connectors generally include double-layer or even multi-layer conductive terminals. The published patent "HDMI male connector for facilitating automated welding of ground wires" with publication number CN213278577U is used as comparative document 1. The male connector includes an upper conductive terminal 10 and a lower conductive terminal 20. The upper conductive terminal 10 and the lower conductive terminal 20 are respectively fixed in a guide groove 40 opened on the surface of an insulating base 30. The applicant pointed out that in comparative document 1, in the process of welding the rear ends of the upper conductive terminal 10 and the lower conductive terminal 20 with the wires respectively, the inner wall of the guide groove 40 will be partially deformed under the high temperature of the welding gun and the resistance of the gun tip due to the material of the insulating base, the quality of the welding gun, the temperature setting during the use of the welding gun, and the pressing force of the welding gun during the welding process. The inner wall of the guide groove 40 will be partially deformed under the high temperature of the welding gun and the resistance of the gun tip. The deformed inner wall of the guide groove 40 will be mixed with the welding material in a molten state, resulting in the solder joint and its The shape of the guide groove 40 is deformed, which affects the machine vision image acquisition and data processing. Especially in the process of batch manual assembly line welding operations, the above problem will cause large detection errors in the process of machine vision inspection of batch products, and qualified products are often discarded as defective products, requiring manual intervention for secondary visual inspection, affecting production efficiency. In one embodiment, the above problem can be partially solved by increasing the material hardness of the insulating base or the insulating body, but this will lead to an increase in raw material costs. At the same time, the material hardness of the insulating base is increased, and large-scale adjustments to the existing production lines and supply chains are required, which is difficult to achieve. At the same time, in the above structure, the solder joints after welding are accommodated in the guide grooves 40, and the amount of data collected by the machine vision image of the solder joints is limited, and the error of machine vision image processing is large. Therefore, the present invention adjusts the structure of the above data line connector to reduce the problems of low efficiency and large errors in the quality inspection of the data line interface solder joints. In the data line connector of the present invention, a mounting groove penetrating the front and rear end surfaces is provided in the middle of the front end of the insulating body, and the mounting groove is used to dock with the tongue piece on the female socket interface, and the upper conductive terminal is inserted from the upper terminal groove and the upper plug hole, and extends backward out of the rear end of the insulating body, and the lower conductive terminal is inserted from the lower terminal groove and the lower plug hole, and extends backward out of the rear end of the insulating body. The parts of the upper conductive terminal and the lower conductive terminal extending from the rear end of the insulating body are used for welding with the wire body. First, during the welding process, the insulating base is not inserted into the mounting groove, and a high-temperature resistant and high-hardness insulating welding base is inserted between the upper conductive terminal and the lower conductive terminal, and the upper conductive terminal, the lower conductive terminal and the wire body are respectively welded on the insulating welding base. After welding, machine vision image inspection and infrared thermal imaging inspection are carried out. For products that pass the inspection, the insulating base is inserted into the installation slot, and the upper conductive terminal and the lower conductive terminal are installed in the guide groove of the insulating base to complete the preliminary assembly of the data cable connector. The insulating base and the insulating body are then covered and fixed by the shielding shell to finally complete the processing of the data cable connector. By splitting the insulating base and the insulating body into a separate design, the influence of the guide groove on the machine vision image inspection can be effectively avoided, making the machine vision image inspection of the solder joint structure clearer and more complete, and at the same time, the data collection volume is larger, which greatly improves the efficiency of the data cable interface solder joints in the machine vision inspection process and reduces the error of data processing.

[0022] A method for producing a high-precision data line comprises the following steps: S100: After temporarily sealing the rear end of the installation groove of the insulating body, an optical microscope camera is used to collect images of the target welding point group from a target detection direction; S200: The image acquisition of the target welding point group includes at least a first target detection direction and a second target detection direction, respectively acquiring a first detection image and a second detection image from the first target detection direction and the second target detection direction, and performing graphic detection after grayscale and binarization processing on the first detection image and the second detection image; S300: Connect the target data line to the rated working circuit, and the infrared thermal imager obtains the first thermal imaging image group and the second thermal imaging image group of the target solder joint group from the first target detection direction and the second target detection direction respectively based on the increasing time points, and performs tracking detection on the first thermal imaging image group and the second thermal imaging image group; As described in the published patent "Detection system for detecting the reliability of circuit board solder joints using infrared multi-point temperature measurement and thermal resistance method" with announcement number CN102183542B, the system of the present invention organically combines an optical microscope camera, an infrared laser and an infrared thermal imager to form a new circuit board solder joint reliability detection system, which has high detection results and can detect 100% of solder joints with more than 50% false solder joint defects, which is unmatched by other existing detection systems and has good development prospects. It can be seen that solder joint detection by optical cameras and infrared thermal imagers is a disclosed technology in the prior art, and the working principles of optical cameras and infrared thermal imagers will not be further elaborated here; In S100, Figure 4 As shown, the target solder joint group includes multiple solder joints at the rear end of the upper conductive terminal. Since the upper conductive terminal and the lower conductive terminal overlap in the vertical direction, if the target solder joint group G is detected from the direction f10, the solder joints on the upper conductive terminal and the lower conductive terminal will overlap, affecting the image acquisition effect of the optical microscope camera. The captured image will have the problem of overlapping interference of the solder joint group shape, so it is necessary to find a suitable direction to detect the target solder joint group G; The target solder joint group G is set at the rear end of the upper conductive terminal. When the target solder joint group is imaged from the direction f1, a relatively complete image of the target solder joint group can be acquired, and the interference of the lower conductive terminal can be avoided. Figure 5 As shown, when the target solder joint group is imaged from the direction f1, due to the presence of the mounting slot 121, the lower terminal groove on the lower inner wall of the mounting slot 121 will form the background of the first detection image group, which will increase the background complexity of the first detection image group and affect the image acquisition effect of the first detection image group. Therefore, before the target solder joint group is imaged, the mounting slot is temporarily sealed. The temporary sealing can be performed with an adhesive tape of the same color as the insulating body. The adhesive tape can provide a relatively neat background for the image acquisition of the target solder joint group, so that the image acquisition effect of the target solder joint group is better. After the mounting slot is temporarily sealed, the target solder joint group is imaged by an optical microscope camera. For qualified products, the insulating base is plugged into the mounting slot, as shown in FIG. Figure 5 As shown, an easy-tear seam Z is provided along the center line of the tape. When the insulating base is inserted into the mounting groove, the tape can be torn following the action of inserting the insulating base into the mounting groove. The torn tape can fill the gap between the insulating base and the mounting groove, so that the sealing performance between the insulating base and the mounting groove is better, and the waterproof sealing effect of the HDMI connector is better. In S200, by coordinating the first target detection direction and the second target detection direction, the target welding point group is imaged from multiple dimensions, thereby improving the accuracy of visual inspection and increasing the efficiency of visual inspection; In S300, after the target data lines are connected to the rated working circuit, the target data lines that cannot work normally are eliminated, and the target data lines that meet the working requirements are continued to the next step of detection, such as Figure 4 As shown, after the target data line is connected to the rated working circuit, the infrared thermal imager obtains the first thermal imaging image group and the second thermal imaging image group of the target solder joint group from the first target detection direction and the second target detection direction based on the increasing time points, so that the thermal imaging images of the target solder joint group at different time points and different angles can be captured, so that the operation status of the solder joint group can be better tracked and analyzed, so that the target solder joint group can be better analyzed, and the detection of the target solder joint group can be more accurate; In the present invention, detection images are obtained by capturing images in multiple different directions, and the target solder joint group is detected from multiple dimensions, so that the detection accuracy is higher, the data volume is richer, and the processing speed is faster. The infrared thermal imager can capture thermal imaging images of the target solder joint group at different time points and different angles, so that the operation status of the solder joint group can be better tracked and analyzed, so that better data analysis can be performed on the target solder joint group, the detection of the target solder joint group is more accurate, the yield rate of data cable production is higher, and the production efficiency is higher.

[0023] In the embodiment of the present invention, the step S100 includes the following operation steps: S110: The intersection of the plane where the upper boundary and the lower boundary of the field of view in the target detection direction are located and the rear end surface of the insulating body is within a first interval, and the first interval includes the area between the vertical projections of the upper end surface of the insulating body and the upper end surface of the lower conductive terminal on the rear end surface of the insulating body; like Figure 4 As shown, in the process of detecting the target solder joint group, the target solder joint group can be understood as the solder joint group at the top in the figure. Similarly, after the data line connector is turned upside down, the solder joint group on the conductive terminal at the top is the target solder joint group; In the direction of target detection, the field of view of the optical microscope camera is limited, such as Figure 2 As shown, the field of view of the optical microscope camera includes the upper boundary and the lower boundary of the field of view in the vertical direction f11 and the left boundary and the right boundary of the field of view in the horizontal direction f12. Since the upper conductive terminal and the lower conductive terminal overlap in the vertical direction f11, when the optical microscope camera is used to collect images of the target solder joint group in the target detection direction, it is necessary to avoid interference between the upper conductive terminal and the lower conductive terminal. In the vertical direction f11, as shown in FIG. Figure 4 As shown, the field of view of the target detection direction is Q1, and the intersection of the plane where the lower boundary of the field of view of the target detection direction is located and the rear end surface of the insulating body is J1. Figure 5As shown, the vertical projection T1 of the upper end surface of the insulating body on the rear end surface of the insulating body, and the vertical projection T2 of the upper end surface of the lower conductive terminal on the rear end surface of the insulating body, as shown in FIG. Figure 4 As shown by the middle dotted line, the intersection of the plane where the lower boundary of the field of view in the target detection direction is located and the rear end surface of the insulating body is within the first interval, which means that when the lower boundary of the field of view in the target detection direction is at the lowest end, it will not interfere with the upper end surface of the lower conductive terminal, and when the upper boundary of the field of view in the target detection direction is at the highest end, it will not exceed the insulating body, thereby ensuring that in the process of the optical microscope camera acquiring images of the target welding point group, the background of the image is more single, the image acquisition is more complete, and the detection effect is better. At the same time, the infrared thermal imager performs infrared thermal imaging detection based on the target detection direction, avoiding thermal imaging interference between the upper conductive terminals and the lower conductive terminals, making the detection effect more accurate. The optical microscope camera and the infrared thermal imager in the present invention have a large detection range, a large amount of data acquisition, and a more accurate detection result.

[0024] In the embodiment of the present invention, the step S100 includes the following operation steps: S120: The intersection of the plane where the left boundary and the right boundary of the field of view in the target detection direction are located and the rear end surface of the insulating body is within a second interval, and the second interval includes the area between the leftmost end and the rightmost end of the insulating body; S130: The left boundary and the right boundary of the field of view in the target detection direction exceed the rear end of the ground terminal; In S120, if Figure 2 As shown, the field of view of the optical microscope camera includes the left boundary and the right boundary of the field of view in the horizontal direction f12, as shown in FIG. Figure 6 As shown, the field of view of the target detection direction is Q1, such as Figure 5 As shown, the vertical projection T3 of the plane where the leftmost end of the insulating body is located on the rear end surface of the insulating body, the vertical projection T4 of the plane where the rightmost end of the insulating body is located on the rear end surface of the insulating body, and the intersection of the plane where the left boundary and the right boundary of the field of view in the target detection direction are located and the rear end surface of the insulating body are within the second interval, that is, the left boundary of the field of view in the target detection direction will not exceed the leftmost end of the insulating body when it is at the leftmost end, and the right boundary of the field of view in the target detection direction will not exceed the rightmost end of the insulating body when it is at the rightmost end, thereby ensuring that the background of the image is more single during the process of the optical microscope camera collecting images of the target solder joint group, avoiding the background exceeding the edge of the insulating body during the process of the optical microscope camera collecting images of the target solder joint group, resulting in a cluttered background, which affects the image collection effect during the visual inspection process; In S130, if Figure 6As shown, in the target detection direction, the ground terminal may cause obstruction of the target welding point group. Therefore, in order to ensure the complete image acquisition of the target welding point group, the left boundary and the right boundary of the field of view in the target detection direction exceed the rear end of the ground terminal.

[0025] In the embodiment of the present invention, step S200 includes the following steps: S210: The first target detection direction and the second target detection direction are respectively perpendicular to a first reference line, and the first reference line is perpendicular to a left end surface of an upper conductive terminal; In S210, Figure 8 and Fig. 9 The figure shows a single solder joint in the target solder joint group. Figure 7 As shown, the target solder joint group has coordinates in three directions, including x, y and z, in three-dimensional space, the first reference line c1 is perpendicular to the left end surface of the upper conductive terminal, and the first target detection direction is perpendicular to the first reference line c1, as shown in FIG. Fig. 9 As shown, the left boundary and the right boundary of the field of view in the first target detection direction can better capture a more complete image above the target welding point group, making the image capture data richer and avoiding incomplete image capture on the other side due to the first target detection direction being biased towards one side.

[0026] In the embodiment of the present invention, step S210 includes the following steps: S211: Acquisition of the first detection image includes the following steps; The front boundary of the field of view in the first target detection direction exceeds the front end of the target welding point group, and the rear boundary of the field of view in the first target detection direction exceeds the rear end of the target welding point group; S212: The graphic detection of the first detection image includes the following steps; In the first detection image, for any connected domain, the respective edge lines are closed to obtain n closed domains S11, S12, ..., S1n. For any closed domain, the front end or the rear end of the edge line is taken as the initial point, and the distances between the left and right pixel points of the edge line of the closed domain are obtained in sequence along the front-to-back direction, and are recorded and stored in sequence as the first width array L11, L12, ..., L1n; The sequence number where the median of L11, L12, ..., L1n is located is recorded as the mark sequence number, and the sequence number where the maximum value of L11, L12, ..., L1n is located is recorded as the target sequence number. The next step is performed if and only if the difference between the mark sequence number and the target sequence number is within a threshold range, and the threshold is less than 1 / 5 of the number of elements in the first width array; Determine whether the difference signs of the previous element and the next element in the range from L11 to the target sequence number are the same, and determine whether the difference signs of the previous element and the next element in the range from the target sequence number to L1n are the same. If the above conditions are met, proceed to the next step; If and only if the differences of adjacent elements are all within the threshold range, the solder joint detection corresponding to the closed domain is qualified; Compare the distance between the front and rear ends of the edge line with the standard value; In S211, Fig. 9 As shown, in order to ensure the integrity of the target solder joint group, the front boundary of the field of view in the first target detection direction needs to exceed the front end of the target solder joint group, and the rear boundary of the field of view in the first target detection direction needs to exceed the rear end of the target solder joint group; In S212, if Fig.10 As shown, taking the front end or the rear end of the edge line as the initial point, the spacing between the left and right pixel points of the edge line of the closed domain is obtained in sequence along the axial direction to obtain the first width array L11, L12, ..., L1n. By comparing the difference between L11, L12, ..., L1n, the change trend of the width of the target solder joint in the front-to-back direction can be determined; like Fig.10 As shown in the figure, for a standard solder joint, its diameter is the largest near the middle and shrinks naturally towards the front and rear ends. The serial number where the median of L11, L12, ..., L1n is located is recorded as the marking serial number, and the serial number where the maximum value of L11, L12, ..., L1n is located is recorded as the target serial number. The marking serial number is the middle position of the target solder joint in the front-to-back direction, and the maximum value is the position where the diameter of the target solder joint is the widest. In theory, the widest position of the diameter of the target solder joint is the middle position, but in the actual processing process, it is difficult to have a perfect solder joint, so the widest position of the diameter of the target solder joint is allowed to shift to the front and rear ends, but if the shift is too much, it will affect the conduction effect of the circuit, so the next step is performed when and only when the difference between the marking serial number and the target serial number is within the threshold range. For the selection of the threshold, for high-precision data lines, it is necessary to be as fine as possible while taking into account the actual processing cost, so the threshold is less than 1 / 5 of the number of elements in the first width array, that is, the deviation between the widest position and the middle position of the diameter of the target solder joint cannot exceed 1 / 5 of the overall length; Determine whether the difference signs between the previous element and the next element in the range from L11 to the target serial number are the same. In the process of gradually moving from the front end to the widest position of the target solder joint diameter, the diameter of the target solder joint gradually increases. Therefore, the difference signs between the previous element and the next element in the range from L11 to the target serial number should all be negative numbers, and the difference signs should be the same. In the process of gradually moving from the widest position of the target solder joint diameter to the rear end, the diameter of the target solder joint gradually decreases, so the difference signs between the previous element and the next element in the range from the target serial number to L1n should all be positive numbers with the same difference signs. If the difference signs of the previous element and the next element at a certain position are different, it means that the target solder joint has a concave defect at that position. For example, if L11 is less than L12, the difference between L11 and L12 is a negative number. If L12 is greater than L13, the difference between L12 and L13 is a positive number, indicating that the position of the target solder joint corresponding to L13 has a concave defect that affects the electrical connection effect of the solder joint. The solder joint is unqualified and the next step is performed if the above conditions are met. If and only if the differences of adjacent elements are all within the threshold range, the solder joint detection corresponding to the closed domain is qualified. For example, if the difference between L11 and L12 is greater than the threshold, it means that although L12 bulges outward, it bulges too much, affecting the overall distribution of the target solder joint group; Similarly, if the difference between L12 and L13 is greater than the threshold, it means that L13 bulges outward too much, indicating that the solder joint has quality problems. L13 to L1n are compared in sequence, so that the target solder joint can be detected more accurately. The distance between the front and rear ends of the edge line is compared with the standard value, that is, it is determined whether the front and rear lengths of the target solder joint reach the predetermined length. A solder joint that is too short will affect the diameter of the electrical connection.

[0027] In the embodiment of the present invention, step S210 includes the following steps: S215: Acquisition of the second detection image includes the following steps; The upper boundary of the field of view in the second target detection direction exceeds the upper end of the target welding point group, and the lower boundary of the field of view in the second target detection direction exceeds the lower end of the target welding point group; S216: The graphic detection of the second detection image includes the following steps: In the second detection image, for any connected domain, the respective edge lines are closed to obtain n closed domains S21, S22, ..., S2n. For any closed domain, the upper end of the edge line is taken as the initial point, and the distances between the left and right pixel points of the edge line of the closed domain are obtained in sequence along the vertical direction, and are recorded and stored in sequence as the second width array L21, L22, ..., L2n; The difference between the next element and the previous element in L21, L22, ..., L2n is judged in sequence. In any closed domain, when the differences between adjacent elements are all positive numbers and within the threshold range, the solder joint detection corresponding to the closed domain is qualified; Compare the distance between the upper and lower ends of the edge line with the standard value; In S215, Fig.11 The figure shows a single solder joint in the target solder joint group. Fig.11 As shown in the figure, it is the rear view of the target solder joint. Fig.11 As shown, in order to ensure the integrity of the target solder joint group, the upper field of view of the first target detection direction needs to exceed the upper end of the target solder joint group, and the lower field of view of the first target detection direction needs to exceed the lower end of the target solder joint group; In S216, if Fig.11 As shown, taking the upper end of the edge line as the initial point, the distances between the left and right pixel points of the edge line of the closed domain are obtained in sequence along the vertical direction, and the records are stored as the second width array L21, L22, ..., L2n. By comparing the difference values ​​of L21, L22, ..., L2n, the change trend of the width of the target solder joint in the vertical direction can be determined. For example, if L22 is greater than L21, it means that at the position of L22, the target solder joint protrudes outwards. If L22 is less than L21, it means that the target solder joint is sunken inwards. For the target solder joint, if the width of the lower end is smaller than the width of the upper end, it means that on the solder joint, the conductive area at the position where the solder joint is connected to the wire is smaller than the area shown above, indicating that there is a welding defect in the solder joint, and the actual conduction capacity of the solder joint is smaller than the area shown above. Similarly, if L13 is greater than L12, it means that at the position of L13, the target solder joint is convex outward. If L13 is less than L12, it means that the target solder joint is concave inward. Comparing L13 to L1n in turn, the differences between adjacent elements are all positive numbers, indicating that the conduction area of ​​the target solder joint always increases downward evenly, thereby ensuring the electrical connection effect of the target solder joint. Compare the distance between the front and rear ends of the edge line with the standard value, that is, determine whether the length of the target solder joint reaches the predetermined length. If the solder joint is too short, it will affect the diameter of the electrical connection. It should be noted that, in order to avoid the influence of the wire on the solder joint detection, during the detection process, the wire is offset toward the lower conductive terminal by an auxiliary fixture to ensure the detection of the upper conductive terminal.

[0028] In the embodiment of the present invention, in step S210, the graphic detection of the second detection image further includes the following steps: S217: In the second detection graph, for any connected domain, the respective edge lines are closed to obtain n closed domains S21, S22, ..., S2n. For any closed domain, the upper end of the edge line is used as the initial point, and the shortest distances between the edge lines of adjacent closed domains are obtained in sequence along the vertical direction, and are recorded and stored as third width arrays L31, L32, ..., L3n respectively. Compare L31, L32, ..., L3n with the standard values ​​respectively; like Figure 2As shown in the figure, in the actual production process, the production requirements of solder joints mainly include the following two aspects: first, whether the solder joint itself meets the circuit operation; second, whether the gap between the solder joints meets the preset specifications and whether there is a risk of short circuit; therefore, when a solder joint can meet the continuous electrical connection operation of its circuit under the rated power state, it is also necessary to determine whether the gap between the solder joints meets the standard, such as Fig.12 As shown, taking the upper end of the edge line as the initial point, the shortest distances between the edge lines of adjacent closed domains are obtained in sequence along the vertical direction, and are recorded and stored in sequence as a third width array L31, L32, ..., L3n, wherein L31, L32, ..., L3n represent the shortest distances between two adjacent solder joints. In the upper conductive terminal, the upper conductive terminal includes a plurality of PIN needles, which need to be spaced apart from each other to avoid short circuits and facilitate subsequent assembly of an insulating base. Therefore, adjacent PIN needles need to be spaced apart by a predetermined distance. L31, L32, ..., L3n are compared with standard values ​​respectively to determine whether the spacing between the PIN needles exceeds the target range.

[0029] In the embodiment of the present invention, step S300 includes the following steps: S310: Acquisition of the first thermal imaging image group includes the following steps: A first time group consisting of a plurality of incremental time points t11, t12, ..., t1n is preset, Based on the time points in the first time group t11, t12, ..., t1n, respectively, a plurality of thermal images P11, P12, ..., P1n are acquired from the first target detection direction; S320: The tracking detection of the first thermal imaging image group includes the following steps: The thermal imaging images P11, P12, ..., P1n are respectively matched and compared with the first detection image, and the thermal imaging points of the thermal imaging images P11, P12, ..., P1n are respectively marked in the closed domains S11, S12, ..., S1n. For any closed domain, if and only if the thermal imaging points in the closed domain are uniformly progressive from the edge line to the middle, proceed to the next step; For any closed domain, the superposition area of ​​the thermal imaging points on the thermal imaging images P11, P12, ..., P1n within the closed domain coincides with the edge line; like Fig.13As shown, during the electrical connection operation between the target solder joint and the upper conductive terminal, the temperature gradually rises with the increase of time, and the positions of the thermal imaging points of the thermal imaging images P11, P12, ..., P1n in the closed domains S11, S12, ..., S1n gradually change, and the area of ​​the thermal imaging points gradually increases. Since the overall structure of the target solder joint is convex in the vertical direction, and the connection between the wire and the upper conductive terminal is generally in the lower half of the target solder joint, in the first detection image, the top of the target solder joint in the vertical direction heats up the slowest. Therefore, in an ideal state, for any closed domain, the thermal imaging points in the closed domain uniformly and gradually progress from the edge line to the middle, and finally the overall temperature of the target solder joint tends to be consistent, then the superimposed area of ​​the thermal imaging points on the thermal imaging images P11, P12, ..., P1n in the closed domain coincides with the edge line; If the progressive manner of the thermal imaging points in a closed domain is abnormal or the connecting line of the thermal imaging points on the thermal imaging images P11, P12, ..., P1n does not coincide with the edge line, it means that there are holes inside the solder joint corresponding to the closed domain and the solder joint is abnormal.

[0030] In the embodiment of the present invention, step S300 includes the following steps: S330: Acquisition of the second thermal imaging image group includes the following steps: A first time group consisting of a plurality of incremental time points t11, t12, ..., t1n is preset, Based on the time points in the first time group t11, t12, ..., t1n, respectively, a plurality of thermal images P21, P22, ..., P2n are acquired from the second target detection direction; S340: The tracking detection of the second thermal imaging image group includes the following steps: The thermal images P21, P22, ..., P2n are respectively matched and compared with the second detection image, and the thermal imaging points of the thermal images P21, P22, ..., P2n are respectively marked in the closed domains S21, S22, ..., S2n. For any closed domain, if and only if the thermal imaging points in the closed domain are uniformly progressive from the middle to both sides, proceed to the next step; For any closed domain, the superposition area of ​​the thermal imaging points on the thermal imaging images P11, P12, ..., P1n in the closed domain coincides with the edge line; like Fig.13As shown, during the electrical connection operation between the target solder joint and the upper conductive terminal, the temperature gradually rises with the increase of time, and the positions of the thermal imaging points of the thermal imaging images P21, P22, ..., P2n in the closed domains S21, S22, ..., S2n gradually change, and the area of ​​the thermal imaging points gradually increases. Since the overall structure of the target solder joint bulges to both sides in the horizontal direction, and the connection between the wire and the upper conductive terminal is generally in the middle of the target solder joint, in the second detection image, the temperature of both sides of the target solder joint in the horizontal direction rises the slowest. Therefore, in an ideal state, for any closed domain, the thermal imaging points in the closed domain evenly and gradually progress from the middle to both sides, and finally the overall temperature of the target solder joint tends to be consistent, then the superposition area of ​​the thermal imaging points on the thermal imaging images P11, P12, ..., P1n in the closed domain coincides with the edge line; If the progressive manner of the thermal imaging points in a closed domain is abnormal or the connecting line of the thermal imaging points on the thermal imaging images P11, P12, ..., P1n does not coincide with the edge line, it means that there are holes inside the solder joint corresponding to the closed domain and the solder joint is abnormal.

[0031] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

Claims

1. A high-precision data line and a production method thereof, characterized in that: It includes a wire body and data wire connectors respectively connected to both ends of the wire body, and the data wire connector includes a shielding shell and an insulating body arranged in the shielding shell; A mounting groove penetrating the front and rear end surfaces is provided in the middle of the front end of the insulating body, and a plurality of upper terminal grooves and lower terminal grooves evenly spaced are respectively provided on the upper and lower inner walls of the mounting groove, and an upper plug hole and a lower plug hole communicating with the rear end of the insulating body are respectively provided on the rear inner walls of the upper terminal groove and the lower terminal groove; The upper terminal groove and the lower terminal groove are respectively inserted with an upper conductive terminal and a lower conductive terminal, and the upper conductive terminal and the lower conductive terminal extend out of the rear end of the insulating body from the upper plug hole and the lower plug hole respectively; An insulating base is provided between the upper conductive terminal and the lower conductive terminal and is plugged into the mounting groove. The upper and lower end surfaces of the insulating base are respectively provided with guide grooves for mounting the upper conductive terminal and the lower conductive terminal. Ground terminals are respectively extended backwards on both sides of the shielding shell.

2. A method for producing a high-precision data line, characterized in that: The steps include: S100: After temporarily sealing the rear end of the installation groove of the insulating body, an optical microscope camera is used to collect images of the target welding point group from the target detection direction; S200: The image acquisition of the target welding point group includes at least a first target detection direction and a second target detection direction, respectively acquiring a first detection image and a second detection image from the first target detection direction and the second target detection direction, and performing graphic detection after grayscale and binarization processing on the first detection image and the second detection image; S300: Connect the target data line to the rated working circuit, and the infrared thermal imager obtains the first thermal imaging image group and the second thermal imaging image group of the target solder joint group from the first target detection direction and the second target detection direction respectively based on the increasing time points, and tracks and detects the first thermal imaging image group and the second thermal imaging image group.

3. A high-precision data line and a production method thereof according to claim 2, characterized in that: The step S100 includes the following steps: S110: The intersection of the plane where the upper boundary and the lower boundary of the field of view in the target detection direction are located and the rear end surface of the insulating body is within a first interval, and the first interval includes the area between the vertical projections of the upper end surface of the insulating body and the upper end surface of the lower conductive terminal on the rear end surface of the insulating body.

4. A high-precision data line and a production method thereof according to claim 2, characterized in that: The step S100 includes the following steps: S120: The intersection of the plane where the left boundary and the right boundary of the field of view in the target detection direction are located and the rear end surface of the insulating body is within a second interval, and the second interval includes the area between the leftmost end and the rightmost end of the insulating body; S130: The left boundary and the right boundary of the field of view in the target detection direction exceed the rear end of the ground terminal.

5. A high-precision data line and a production method thereof according to claim 1, characterized in that: Step S200 includes the following steps: S210: The first target detection direction and the second target detection direction are respectively perpendicular to a first reference line, and the first reference line is perpendicular to a left end surface of an upper conductive terminal.

6. A high-precision data line and a production method thereof according to claim 5, characterized in that: Step S210 includes the following steps: S211: Acquisition of the first detection image includes the following steps; The front boundary of the field of view in the first target detection direction exceeds the front end of the target welding point group, and the rear boundary of the field of view in the first target detection direction exceeds the rear end of the target welding point group; S212: The graphic detection of the first detection image includes the following steps; In the first detection image, for any connected domain, the respective edge lines are closed to obtain n closed domains S11, S12, ..., S1n. For any closed domain, the front end or the rear end of the edge line is taken as the initial point, and the distances between the left and right pixel points of the edge line of the closed domain are obtained in sequence along the front-to-back direction, and are recorded and stored in sequence as the first width array L11, L12, ..., L1n; The sequence number where the median of L11, L12, ..., L1n is located is recorded as the mark sequence number, and the sequence number where the maximum value of L11, L12, ..., L1n is located is recorded as the target sequence number. The next step is performed if and only if the difference between the mark sequence number and the target sequence number is within a threshold range, and the threshold is less than 1 / 5 of the number of elements in the first width array; Determine whether the difference signs of the previous element and the next element in the range from L11 to the target sequence number are the same, and determine whether the difference signs of the previous element and the next element in the range from the target sequence number to L1n are the same. If the above conditions are met, proceed to the next step; If and only if the differences of adjacent elements are all within the threshold range, the solder joint detection corresponding to the closed domain is qualified; Compare the distance between the front and rear ends of the edge line with the standard value.

7. A high-precision data line and a production method thereof according to claim 5, characterized in that: Step S210 includes the following steps: S215: Acquisition of the second detection image includes the following steps; The upper boundary of the field of view in the second target detection direction exceeds the upper end of the target welding point group, and the lower boundary of the field of view in the second target detection direction exceeds the lower end of the target welding point group; S216: The graphic detection of the second detection image includes the following steps: In the second detection image, for any connected domain, the respective edge lines are closed to obtain n closed domains S21, S22, ..., S2n. For any closed domain, the upper end of the edge line is taken as the initial point, and the distances between the left and right pixel points of the edge line of the closed domain are obtained in sequence along the vertical direction, and are recorded and stored in sequence as the second width array L21, L22, ..., L2n; The difference between the next element and the previous element in L21, L22, ..., L2n is judged in sequence. In any closed domain, when the differences between adjacent elements are all positive numbers and within the threshold range, the solder joint detection corresponding to the closed domain is qualified; Compare the distance between the upper and lower ends of the edge line with the standard value.

8. A high-precision data line and a production method thereof according to claim 7, characterized in that: In step S210, the graphic detection of the second detection image further includes the following steps: S217: In the second detection graph, for any connected domain, the respective edge lines are closed to obtain n closed domains S21, S22, ..., S2n. For any closed domain, the upper end of the edge line is used as the initial point, and the shortest distances between the edge lines of adjacent closed domains are obtained in sequence along the vertical direction, and are recorded and stored as third width arrays L31, L32, ..., L3n respectively. Compare L31, L32, ..., L3n with the standard values ​​respectively.

9. A high-precision data cable and a production method thereof according to any one of claims 1 to 8, characterized in that: The step S300 includes the following steps: S310: Acquisition of the first thermal imaging image group includes the following steps: A first time group consisting of a plurality of incremental time points t11, t12, ..., t1n is preset, Based on the time points in the first time group t11, t12, ..., t1n, respectively, a plurality of thermal images P11, P12, ..., P1n are acquired from the first target detection direction; S320: The tracking detection of the first thermal imaging image group includes the following steps: The thermal imaging images P11, P12, ..., P1n are respectively matched and compared with the first detection image, and the thermal imaging points of the thermal imaging images P11, P12, ..., P1n are respectively marked in the closed domains S11, S12, ..., S1n. For any closed domain, if and only if the thermal imaging points in the closed domain are uniformly progressive from the edge line to the middle, proceed to the next step; For any closed domain, the superimposed area of ​​the thermal imaging points on the thermal imaging images P11, P12, ..., P1n within the closed domain coincides with the edge line.

10. A high-precision data cable and a production method thereof according to any one of claims 1 to 8, characterized in that: The step S300 includes the following steps: S330: Acquisition of the second thermal imaging image group includes the following steps: A first time group consisting of a plurality of incremental time points t11, t12, ..., t1n is preset, Based on the time points in the first time group t11, t12, ..., t1n, respectively, a plurality of thermal images P21, P22, ..., P2n are acquired from the second target detection direction; S340: The tracking detection of the second thermal imaging image group includes the following steps: The thermal images P21, P22, ..., P2n are respectively matched and compared with the second detection image, and the thermal imaging points of the thermal images P21, P22, ..., P2n are respectively marked in the closed domains S21, S22, ..., S2n. For any closed domain, if and only if the thermal imaging points in the closed domain are uniformly progressive from the middle to both sides, proceed to the next step; For any closed domain, the superimposed area of ​​the thermal imaging points on the thermal imaging images P11, P12, ..., P1n within the closed domain coincides with the edge line.

Images