Method and system for detecting a film on a pcm panel

Abstract

The application provides a PCM plate film coating detection method, which is used for respectively performing optical detection on a protective film and a substrate before film coating, and obtaining pre-pasting parameters, wherein the pre-pasting parameters include initial uniformity and surface state parameters of the protective film, initial flatness and position offset of the substrate; a visual detection device is arranged between the protective film and the substrate, the visual detection device is used for detecting a fitting angle between the substrate and the protective film in a fitting process, and fitting parameters are generated; optical detection is performed on a composite after film pasting is completed, and post-pasting parameters are obtained, wherein the fitting parameters include protective film surface uniformity parameters, relative position deviation parameters and relative angle parameters of the film and the substrate; the pre-pasting parameters, the fitting parameters and the post-pasting parameters are obtained as reference detection data, defect reasons are obtained through a multi-dimensional comparison strategy, and corresponding adjustment strategies are generated according to the defect reasons.

Description

Technical Field

[0001] This invention relates to coating inspection, and more particularly to a method and system for inspecting the coating of PCM boards. Background Technology

[0002] In the production and processing of PCM boards, the lamination process is a crucial step in improving the surface protection performance and appearance quality of the PCM boards. The bonding precision between the protective film and the substrate directly determines the finished product qualification rate of the PCM boards. However, existing PCM board lamination inspection technologies still have many technical shortcomings, making it difficult to meet the demands of high-precision and highly automated production. Firstly, the testing process is fragmented, lacking the ability to link parameters across the entire process. Existing technologies mostly test the protective film or substrate in the pre-application stage separately, or only conduct random inspections on the finished product after lamination. They do not systematically collect and correlate pre-application parameters, lamination process parameters, and post-application parameters, making it impossible to trace defects from the source to the finished product, which can easily lead to errors in determining the cause of defects.

[0003] Secondly, the detection of bonding deviation is limited to a single dimension, making it difficult to accurately pinpoint the source of the deviation. Existing methods for detecting bonding angle and position deviations mostly use a single baseline for calculation, which cannot distinguish whether the deviation originates from the initial alignment before bonding, upstream process issues, or abnormal actions or parameters of the actuator during bonding. This results in a lack of targeted deviation correction, leading to repeated adjustments and reduced production efficiency.

[0004] Third, the logic for determining the cause of defects is simple, relying heavily on human experience and having a low degree of standardization. Existing technologies mostly rely on the comparison of a single parameter to determine coating defects, without establishing a multi-dimensional parameter comparison and determination system. This results in insufficient ability to distinguish between various similar defects such as uneven substrate surface, film tension deviation, abnormal correction device, and pressing deformation, which easily leads to misjudgment and omission. Furthermore, the manual intervention method is inefficient and inconsistent, making it difficult to adapt to the needs of large-scale production lines. Summary of the Invention

[0005] In view of the shortcomings of the prior art, the purpose of this invention is to provide a PCM board coating detection method and system to overcome the above-mentioned defects in the prior art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: PCM board coating inspection methods include: The pre-attachment inspection step is used to perform optical inspection on the protective film and the substrate respectively before lamination to obtain pre-attachment parameters. The pre-attachment parameters include the initial uniformity and surface state parameters of the protective film, the initial flatness of the substrate, and the position offset. In the film lamination inspection step, a vision inspection device is set between the protective film and the substrate. The vision inspection device is used to detect the bonding angle between the substrate and the protective film during the bonding process and generate bonding parameters. The post-application inspection step involves optically inspecting the composite after the film has been applied to obtain post-application parameters, including the protective film surface uniformity parameters, the relative positional deviation parameters between the film and the substrate, and the relative angle parameters. The defect analysis and adjustment steps involve obtaining pre-attachment parameters, bonding parameters, and bonding parameters as benchmark detection data, and using a multi-dimensional comparison strategy to identify the causes of defects, and then generating corresponding adjustment strategies based on the causes of defects. Preferably, the optical inspection includes transmission optical inspection and reflection optical inspection. The transmission optical inspection uses a light source to emit a transmission beam, which is then used to inspect the protective film. The transmission beam is used to collect the transmission spectrum data of the protective film, and the thickness value of the protective film in spatial position is calculated based on the interference model of the protective film. According to the thickness value of the protective film, the initial uniformity and surface state parameters of the protective film are obtained. The reflection optical inspection uses a light source to emit a reflection beam, which is then used to illuminate the substrate surface to collect the reflection image data of the substrate and obtain the reflectivity distribution of the substrate surface. According to the mapping relationship between the reflectivity distribution and the flatness of the substrate, the initial flatness of the substrate is obtained.

[0007] Preferably, the bonding detection step includes: The image acquisition sub-step acquires an image of the composite as the image to be analyzed, and acquires a first reference line with the edge of the protective film as the reference line and a second reference line with the substrate as the reference line in the image to be analyzed. The deviation acquisition sub-step involves calculating the relative position deviation parameter and the relative angle deviation parameter between the protective film and the substrate, with the first baseline as a reference, to obtain the first position deviation parameter and the first angle deviation parameter. Then, with the second baseline as a reference, the relative position deviation parameter and the relative angle deviation parameter between the protective film and the substrate are calculated to obtain the second position deviation parameter and the second angle deviation parameter. The deviation comparison step compares the first position deviation parameter, the first angle deviation parameter, the second position deviation parameter, and the second angle deviation parameter to obtain the relative position deviation parameter and the relative angle parameter between the film and the substrate.

[0008] Preferably, the method further includes a deviation source acquisition sub-step. If the difference between the first position deviation parameter and the second position deviation parameter is within a first preset threshold range, and the difference between the first angle deviation parameter and the second angle deviation parameter is within a second preset threshold range, then the deviation is determined to mainly originate from the initial alignment process or upstream process before bonding; otherwise, the deviation is determined to mainly originate from the action or parameter change of the bonding actuator during the bonding process.

[0009] Preferably, the causes of the defects include uneven substrate surface, uneven thickness of protective film, deformation caused by film tension deviation, abnormal tension adjustment of the correction device, and deformation caused by pressing. The adjustment strategies include adjusting the tension of the protective film, adjusting the tension of the correction device, and adjusting the pressing force.

[0010] Preferably, the film-attachment detection step includes: before attachment, acquiring edge feature images of the protective film and the substrate, extracting the intersection points of the protective film and the substrate edges as feature points, and acquiring the theoretical fixed angle; during attachment, simultaneously acquiring edge feature images of the protective film and the substrate, acquiring the spatial attachment angle, and after correcting the feature points according to the vibration correction compensation model, acquiring the relative attachment angle; comparing the relative attachment angle with the theoretical fixed angle, and if the difference exceeds the set tolerance, determining that the relative attachment angle is abnormal.

[0011] Preferably, the multi-dimensional comparison strategy includes comparing the initial uniformity of the protective film and the surface uniformity parameters of the protective film. If the surface uniformity parameters are unqualified but the initial uniformity is qualified, it is determined that the substrate surface is uneven. The relative angle deviation between the film and the substrate is extracted. Combined with the surface uniformity parameters of the protective film and the relative position deviation parameters between the film and the substrate, the influence of the bonding angle on the bonding effect is analyzed. The initial flatness of the substrate is compared with the relative position deviation parameters between the film and the substrate. If the initial flatness of the substrate is qualified, but the relative position deviation is abnormal, it is determined that the film tension is abnormal or the correction device is abnormal.

[0012] Preferably, when the adjustment strategy requires modification of the production line and the current batch of products can be discarded, an extreme testing step is performed. The extreme testing step includes extreme adjustment of the tension of the protective film, changing the effective thickness and stress distribution of the protective film, repeating the testing step under extreme tension, obtaining verification testing data, comparing the verification testing data with the benchmark testing data, and calculating the change in the testing accuracy index. The testing accuracy includes thickness detection error, defect detection error, edge alignment judgment error, etc. When the change in the testing accuracy index meets the preset validity threshold, the proposed production line modification scheme is determined to be effective, and the determined modification parameters are output.

[0013] PCM board coating inspection system includes: The pre-attachment detection module is used to perform optical detection on the protective film and the substrate respectively before lamination to obtain pre-attachment parameters, including the initial uniformity and surface state parameters of the protective film, and the initial flatness and position offset of the substrate. The film bonding detection module has a vision detection device between the protective film and the substrate. The vision detection device is used to detect the bonding angle between the substrate and the protective film during the bonding process and generate bonding parameters. The post-application inspection module performs optical inspection on the composite after the film is applied to obtain post-application parameters, including the protective film surface uniformity parameters, the relative position deviation parameters between the film and the substrate, and the relative angle parameters. The defect analysis and adjustment module acquires pre-attachment parameters, bonding parameters, and bonding parameters as benchmark detection data. It also uses a multi-dimensional comparison strategy to identify the causes of defects and generates corresponding adjustment strategies based on these causes.

[0014] Preferably, the bonding detection module also includes a light group, which is positioned above the composite and has the same length as the width of the composite.

[0015] The beneficial effects of this invention are: It achieves integrated parameter detection throughout the entire lamination process, constructing a complete data closed loop from pre-lamination to post-lamination. This invention, through the coordinated operation of pre-lamination detection, lamination detection, and post-lamination detection, systematically collects pre-lamination parameters of the protective film and substrate, angle and deviation parameters during lamination, and performance parameters of the post-lamination composite. It integrates scattered detection data into benchmark detection data, providing comprehensive and continuous data support for defect tracing. It innovates a dual-benchmark deviation detection and comparison method, accurately locating the source of deviation. By calculating deviation parameters using the edge of the protective film and the substrate as benchmarks respectively, and comparing the difference range of the two sets of deviation parameters, this invention can clearly distinguish whether the deviation originates from the initial alignment before lamination, upstream processes, or the actions of the actuators and parameter changes during lamination. This achieves precise tracing of the deviation source, providing a clear direction for targeted deviation correction and improving production line debugging efficiency.

[0016] This invention establishes a multi-dimensional, standardized defect identification strategy to improve the accuracy and automation of defect cause identification. Through multi-dimensional strategies such as cross-stage comparison of protective film uniformity, correlation analysis of bonding angle and bonding effect, and comparison of substrate flatness and relative positional deviation, combined with preset judgment rules, it achieves automated and standardized differentiation of various defect causes, including substrate surface unevenness, film tension deviation, and abnormality of the correction device. This replaces traditional manual experience-based judgment methods, effectively reducing the rate of misjudgment and missed judgment, and improving the consistency and efficiency of defect identification. Attached Figure Description

[0017] Figure 1This is an overall flowchart of the present invention; Figure 2 This is a flowchart of the deviation analysis of the present invention. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] It should be noted that when a component is described as "fixed to" another component, it can be directly on the other component or may have a component in between. When a component is considered "connected to" another component, it can be directly connected to the other component or may have a component in between. When a component is considered "set on" another component, it can be directly set on the other component or may have a component in between. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this document are for illustrative purposes only.

[0020] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0021] The embodiments of the present invention will be further described in detail below with reference to the accompanying drawings: PCM board coating testing methods, such as Figures 1 to 2 As shown, it includes: The pre-lamination inspection step is used to perform optical inspections on both the protective film and the substrate before lamination to obtain pre-lamination parameters. These parameters include the initial uniformity and surface condition parameters of the protective film, and the initial flatness and positional offset of the substrate. Before the lamination process begins, a comprehensive understanding of the initial state information of the protective film and the substrate is obtained, providing reliable raw data support for precise control and defect tracing in the subsequent lamination process. This step employs two specialized inspection methods—transmissive optical inspection and reflective optical inspection—to perform comprehensive, high-precision optical scanning and data analysis on both the protective film and the substrate, ultimately obtaining a complete pre-lamination parameter system covering the initial uniformity and surface condition parameters of the protective film, as well as the initial flatness and positional offset of the substrate.

[0022] Optical inspection includes transmission optical inspection and reflection optical inspection. Transmission optical inspection uses a light source to emit a transmitted light beam, which is then used to inspect the protective film. The transmitted light beam is used to collect the transmission spectrum data of the protective film, and the thickness value of the protective film at a spatial location is calculated based on the protective film interference model. Based on the thickness value, the initial uniformity and surface state parameters of the protective film are obtained. Transmission optical inspection is specifically used for detecting the initial state of the protective film, and its technical principle is based on the comprehensive application of optical transmission and interference effects. During the inspection process, a dedicated light source emits a highly stable transmission light beam with fixed wavelength characteristics. This beam can penetrate the protective film and form a transmission spectrum signal carrying information about the internal structure and surface state of the protective film. After accurately acquiring these spectral signals, the inspection system inputs them into a preset protective film interference model for inversion calculation. The protective film interference model is a data analysis model built on optical interference theory, which can calculate the actual thickness of the protective film at the corresponding location based on the differences in spectral signals at different spatial locations. By systematically collecting and analyzing thickness data from multiple detection points across the entire protective film, if the thickness values ​​at each detection point are concentrated and the differences are controlled within a reasonable range, it indicates that the initial uniformity of the protective film meets the requirements for lamination. If the thickness values ​​have a large dispersion, the initial uniformity is deemed unqualified. Simultaneously, by combining the characteristics and distribution patterns of abnormal fluctuations in the transmission spectrum signal, it is possible to accurately identify whether there are defects such as scratches, stains, or damage on the protective film surface, thereby forming comprehensive surface state parameters and providing a crucial basis for determining whether the protective film meets the bonding conditions. Reflective optical inspection uses a light source to emit a reflected beam that illuminates the substrate surface, collecting reflective image data of the substrate and obtaining the reflectivity distribution of the substrate surface. Based on the mapping relationship between the reflectivity distribution and the substrate flatness, the initial flatness of the substrate is obtained. Reflective optical inspection focuses on the initial state assessment of the substrate, its core being the use of the correlation between light reflection characteristics and substrate surface morphology to achieve the detection target. During inspection, the reflected beam emitted by the light source illuminates the substrate surface uniformly at a set angle. The flatness of different areas of the substrate surface will cause differences in the reflection angle and intensity of the reflected beam. The detection system captures reflective image data of the substrate surface using high-precision image acquisition equipment. It then performs a series of analytical operations, including grayscale processing and feature extraction, to obtain the reflectivity distribution of the substrate surface. In areas with a smooth substrate surface, the propagation path of the reflected light beam is relatively regular, resulting in stable and uniform reflectivity values. However, areas with protrusions, depressions, or bends cause scattering or refraction of the reflected light beam, leading to significant fluctuations in reflectivity values ​​in the corresponding areas. Based on the inherent mapping relationship between reflectivity distribution and substrate flatness, the initial flatness of the substrate can be accurately determined by quantitatively analyzing the amplitude, range, and distribution patterns of reflectivity fluctuations.In addition, by comparing the actual position information of the substrate with the preset standard reference position, the offset distance and direction of the two in the spatial coordinate system can be calculated to obtain the position offset of the substrate, providing accurate data reference for the alignment adjustment in the subsequent bonding process, and ensuring that the protective film and the substrate can be accurately aligned.

[0023] In the film lamination inspection step, a vision inspection device is set between the protective film and the substrate. The vision inspection device is used to detect the lamination angle between the substrate and the protective film during the lamination process and generate lamination parameters. The angle between the substrate and the protective film is dynamically monitored during the lamination process. By deploying a vision inspection device with high-speed image acquisition and real-time processing capabilities between the two, the changes in lamination posture are captured throughout the process to generate accurate lamination parameters.

[0024] The film lamination inspection process includes: before lamination, acquiring edge feature images of the protective film and the substrate, extracting the intersection points of the protective film and substrate edges as feature points, and obtaining the theoretical fixed angle; during lamination, simultaneously acquiring edge feature images of the protective film and the substrate, obtaining the spatial lamination angle, and after correcting the feature points according to a vibration correction compensation model, obtaining the relative lamination angle; comparing the relative lamination angle with the theoretical fixed angle, and if the difference exceeds the set tolerance, the relative lamination angle is determined to be abnormal. Before lamination starts, the vision inspection device first acquires edge feature images of the protective film and the substrate. After preprocessing such as image noise reduction and contour enhancement, it automatically identifies highly recognizable feature points at the intersection of the two edges. Based on the spatial positional relationship of these feature points, the theoretical fixed angle that lamination must follow is determined through geometric logic operations. This angle is a standard posture reference established in combination with product specifications and process requirements.

[0025] During the bonding process, the vision inspection device continuously acquires edge feature images at a preset frequency to obtain the spatial bonding angle in real time. Considering that the production line operation may generate slight vibrations, causing deviations in the coordinates of feature points, the system introduces a vibration correction compensation model. This model is trained based on a large amount of production line vibration data and can accurately correct deviations and restore the true position according to the feature point offset patterns and vibration characteristics, thereby obtaining the relative bonding angle.

[0026] The relative fitting angle is compared with the theoretical fixed angle, and the tolerance is set according to the allowable fluctuation range of the angle determined by product quality standards and process precision requirements. If the difference between the two exceeds this range, the relative fitting angle is directly judged to be abnormal. This provides a clear basis for timely investigation of problems such as parameter drift of the fitting actuator and wear of mechanical parts, ensuring the accuracy and controllability of the fitting process.

[0027] The post-lamination inspection step involves optical inspection of the composite after lamination to obtain post-lamination parameters, including the uniformity of the protective film surface, the relative positional deviation between the film and the substrate, and the relative angle parameters. By conducting comprehensive optical inspection of the composite after lamination, accurate post-lamination parameters reflecting the lamination quality are obtained. Simultaneously, multi-step deviation analysis and traceability logic are used to identify the root causes of deviations, providing direct and reliable data support for subsequent defect analysis and production line adjustments. The post-lamination parameters obtained in this step cover the uniformity of the protective film surface, the relative positional deviation between the film and the substrate, and the relative angle parameters. Through systematic image acquisition, deviation calculation, comparative analysis, and deviation source identification, a comprehensive evaluation of the lamination results and problem tracing are achieved.

[0028] The bonding test steps include: The image acquisition sub-step acquires an image of the composite as the image to be analyzed, and separately acquires a first baseline with the edge of the protective film as the baseline and a second baseline with the substrate as the baseline. In this sub-step, a dedicated optical inspection device performs a full-area scan of the composite, acquiring a high-definition, high-resolution image as the image to be analyzed. To ensure the comprehensiveness and accuracy of the deviation calculation, the system extracts two baselines from the image to be analyzed: one based on the edge contour of the protective film, and the other based on the edge contour of the substrate. The extraction process of these two baselines undergoes rigorous image preprocessing, including noise filtering, edge enhancement, and contour extraction, effectively eliminating the influence of impurities, light reflection, and other interference factors in the image, ensuring that the baselines accurately represent the actual edge positions of the protective film and the substrate, laying a precise reference foundation for subsequent deviation calculations.

[0029] The deviation acquisition sub-step calculates the relative positional and angular deviation parameters between the protective film and the substrate using a first baseline as a reference, yielding the first positional deviation parameter and the first angular deviation parameter. Then, using a second baseline as a reference, the same parameters are calculated to obtain the second positional and angular deviation parameters. This dual-baseline reference calculation method ensures comprehensive acquisition of deviation parameters. When the first baseline is used as a fixed reference standard, the system uses geometric position analysis and angle calculation logic to measure the degree of spatial deviation between the protective film and the substrate, as well as the angular deviation between them, thus obtaining the first positional and angular deviation parameters. Similarly, when the second baseline is used as a fixed reference standard, the second positional and angular deviation parameters are calculated and obtained using the same calculation logic and analysis dimensions. This dual-baseline reference calculation method captures the relative position and angular relationship between the protective film and the substrate from different perspectives, avoiding potential omissions or calculation errors that might occur with a single baseline reference, making the acquisition of deviation parameters more comprehensive and objective.

[0030] The deviation comparison step compares the first positional deviation parameter, the first angle deviation parameter, the second positional deviation parameter, and the second angle deviation parameter to obtain the relative positional deviation parameter and the relative angle parameter between the film and the substrate. The four deviation parameters are then cross-compared and comprehensively analyzed. By comparing the numerical differences between the first and second positional deviation parameters, and the numerical differences between the first and second angle deviation parameters, and considering the inherent correlation between the two parameters, interference factors caused by errors in a single baseline are eliminated. Finally, the relative positional deviation parameters and relative angle parameters that accurately reflect the bonding state between the film and the substrate are precisely determined, providing core data indicators for bonding quality assessment.

[0031] The process also includes a deviation source acquisition sub-step. If the difference between the first position deviation parameter and the second position deviation parameter is within a first preset threshold range, and the difference between the first angle deviation parameter and the second angle deviation parameter is within a second preset threshold range, then the deviation is determined to mainly originate from the initial alignment process before bonding or the upstream process. Otherwise, the deviation is determined to mainly originate from the action or parameter change of the bonding actuator during the bonding process. The specific stage at which the deviation occurs is clearly identified through preset judgment logic. The first and second preset thresholds are allowable fluctuation ranges for deviation established based on product process requirements, production precision standards, and a large amount of practical data. They are used to define whether the deviation parameters calculated from different baselines are within a reasonable difference range. If the difference between the first position deviation parameter and the second position deviation parameter is within the first preset threshold range, and the difference between the first angle deviation parameter and the second angle deviation parameter is within the second preset threshold range, it indicates that the deviation exhibits consistency under different baseline references. Therefore, it is determined that the deviation mainly originates from the initial alignment process before bonding or the upstream process, meaning that the protective film and the substrate already have positional or angular deviations before entering the bonding stage. If one or both of the two differences exceed the corresponding preset threshold, it indicates that the deviation was generated during the bonding process, mainly due to abnormal operation or parameter changes of the bonding actuator, such as mechanical wear of the actuator, fluctuations in operating speed, or improper pressure adjustment.

[0032] The defect analysis and adjustment steps involve acquiring pre-attachment parameters, bonding parameters, and post-attachment parameters as benchmark inspection data. A multi-dimensional comparison strategy is used to identify the cause of the defect and generate corresponding adjustment strategies based on this cause. This process integrates data resources from each previous inspection stage, using standardized, multi-dimensional analysis logic to accurately pinpoint the root cause of the defect, thereby generating targeted production line adjustment plans and achieving closed-loop management from inspection data to quality improvement. This step first collects the initial state data obtained from pre-attachment inspection, the process parameters captured by film-attachment inspection, and the finished product state parameters obtained from post-attachment inspection. These three types of data are integrated into a complete benchmark inspection dataset, providing comprehensive and coherent data support for subsequent defect analysis and ensuring the objectivity and accuracy of the analysis results. After identifying the cause of the defect, the system generates corresponding adjustment strategies based on preset strategy matching rules. For defects such as uneven substrate surface, upstream processes need to be coordinated to optimize the substrate processing technology and improve substrate flatness; for issues of uneven protective film thickness, the incoming raw material inspection standards need to be strengthened to select qualified protective films. If the defect originates from deformation caused by membrane tension deviation, the adjustment strategy is to precisely adjust the protective membrane tension output value to ensure uniform tension distribution. For abnormal tension adjustment of the correction device, the tension sensing module and adjustment mechanism of the correction device need to be calibrated to ensure tension control accuracy. For deformation caused by pressing, the pressing force and uniformity are optimized by adjusting the pressure output parameters of the pressing mechanism.

[0033] Defects can be caused by uneven substrate surface, uneven thickness of protective film, deformation caused by film tension deviation, abnormal tension adjustment of the web guiding device, and deformation caused by pressing. Adjustment strategies include adjusting the tension of the protective film, adjusting the tension of the web guiding device, and adjusting the pressing force.

[0034] The multi-dimensional comparison strategy includes comparing the initial uniformity and surface uniformity parameters of the protective film. If the surface uniformity parameters are unqualified but the initial uniformity is qualified, it is determined that the substrate surface is uneven. The relative angular deviation between the film and the substrate is extracted and analyzed in conjunction with the surface uniformity parameters and the relative positional deviation parameters to assess the impact of the bonding angle on the bonding effect. The initial flatness of the substrate is compared with the relative positional deviation parameters. If the initial flatness of the substrate is qualified but the relative positional deviation is abnormal, it is determined that the film tension is unqualified or the correction device is malfunctioning. The initial uniformity of the protective film reflects the state of the raw materials before lamination, while the surface uniformity parameters reflect the actual shape of the protective film after lamination. A systematic comparison of the two can clearly define the attribution of defects. If the surface uniformity parameters after lamination do not meet the preset standard, but the initial uniformity before lamination meets the requirements, it indicates that the protective film itself is of good quality, and the defect is caused by the influence of the substrate surface morphology during the lamination process. Therefore, the cause of the defect can be determined as uneven substrate surface.

[0035] The relative angular deviation between the film and the substrate, obtained from post-lamination testing, was extracted. Combined with the surface uniformity parameters and relative positional deviation parameters of the protective film, a multi-parameter linkage analysis model was constructed. By analyzing the variation patterns of surface uniformity and positional deviation under different angular deviations, the influence of the lamination angle on the lamination effect can be quantified, clarifying whether angular anomalies are the dominant factor causing lamination defects, and providing a precise basis for formulating subsequent adjustment strategies.

[0036] The initial flatness of the substrate is a fundamental indicator of its condition before bonding. If this indicator meets the process requirements, but the relative position deviation detected after bonding is abnormal, it indicates that the deviation is not caused by the substrate's own shape, but rather by external force or abnormal equipment parameters during the bonding process. Based on the production process logic, such anomalies are usually related to improper control of the protective film tension or abnormal operation of the web-aligning device. Therefore, the defect can be determined to be caused by film tension deviation or abnormal tension adjustment of the web-aligning device.

[0037] When adjusting the strategy requires modifications to the production line, and the current batch of products can be discarded, an extreme testing step is executed. This extreme testing step involves extreme adjustments to the tension of the protective film, changing its effective thickness and stress distribution. The testing steps are repeated under extreme tension to obtain verification data. This verification data is compared with baseline data, and the changes in testing accuracy indicators are calculated. Testing accuracy includes thickness detection error, defect detection error, and edge alignment judgment error. When the changes in testing accuracy indicators meet a preset validity threshold, the proposed production line modification plan is deemed effective, and the determined modification parameters are output. The extreme testing step is a crucial supplementary step in verifying production line modification plans, applicable to scenarios where the adjustment strategy involves changes to core production line parameters and the current batch of products can be discarded. By simulating extreme conditions, the stability and effectiveness of the proposed production line modification plan are verified, ensuring that the modification parameters can accurately address coating defects and avoid decreased production efficiency or product quality fluctuations due to blind adjustments. This step artificially creates an extreme tension environment, repeats the entire process testing, and compares data differences, providing a scientific and reliable verification basis for the final determination of the modification plan.

[0038] The adjustment strategy can only be implemented when it involves substantial modifications to key production line parameters such as tension control and pressing force, and when the current batch of products cannot meet quality requirements due to defects and can be discarded.

[0039] During the testing phase, the core operation involves extreme adjustments to the tension of the protective film. These extreme adjustments are not arbitrary or random changes, but rather precise control within reasonable process boundaries, targeting either the upper or lower limit of the tension adjustment, based on a predetermined correction plan. The purpose of this extreme adjustment is to alter the stress state of the protective film, thereby changing its effective thickness and internal stress distribution. Changes in tension cause corresponding stretching or contraction deformation of the protective film, resulting in regular variations in the effective thickness of different areas and a differentiated distribution of internal stress. These changes in physical properties under extreme conditions can amplify the improvement effect of the correction plan on defects or expose potential problems, making the verification results more convincing.

[0040] After the extreme tension condition stabilizes, the system repeats the entire testing process, including pre-application testing, film application testing, and post-application testing. This testing strictly adheres to the same standards and procedures as the benchmark testing, ensuring the comparability of the collected verification testing data with the benchmark data. Through repeated testing throughout the entire process, the system can comprehensively capture the changes in the bonding state between the protective film and the substrate under extreme tension conditions, obtaining a complete verification testing dataset covering pre-application parameters, bonding parameters, and post-application parameters.

[0041] In the data comparison and judgment phase, the verification test data and the benchmark test data are first compared and analyzed item by item. The focus is on calculating the changes in the detection accuracy indicators. The thickness detection error included in the detection accuracy reflects the deviation of the protective film thickness detection result from the true value under extreme tension; the defect detection error reflects the change in the system's accuracy in identifying coating defects; and the edge alignment judgment error characterizes the detection deviation in the alignment accuracy between the film and the substrate edges. Through quantitative analysis of the changes in these indicators, the impact of extreme tension adjustments on the test results can be clearly presented.

[0042] The preset effectiveness threshold is a judgment criterion established based on extensive production practice data and process quality standards. It is used to measure whether the improvement effect of the correction plan meets the expected requirements. When the change in the detection accuracy index meets the threshold requirement, it indicates that the proposed production line correction plan can effectively improve coating defects under extreme operating conditions and has practical application value. At this time, the correction plan is deemed effective, and the verified correction parameters are output. If the index change does not meet the effectiveness threshold, it indicates that there is room for optimization in the correction plan. It is necessary to return to the defect analysis stage to readjust the correction direction until an effective production line correction plan is formed. The entire extreme testing procedure, through rigorous operating condition simulation, data comparison, and scientific judgment, provides a solid technical guarantee for production line correction, ensuring that the adjusted production line can stably output high-quality products.

[0043] PCM board coating inspection system includes: The pre-attachment detection module is used to perform optical detection on the protective film and the substrate before lamination to obtain pre-attachment parameters, including the initial uniformity and surface state parameters of the protective film, and the initial flatness and position offset of the substrate. The film bonding detection module has a vision detection device between the protective film and the substrate. The vision detection device is used to detect the bonding angle between the substrate and the protective film during the bonding process and generate bonding parameters. The post-lamination inspection module performs optical inspection on the composite after the film is applied to obtain post-lamination parameters, including the surface uniformity of the protective film, the relative positional deviation between the film and the substrate, and the relative angle parameters. The defect analysis and adjustment module acquires pre-attachment parameters, bonding parameters, and bonding parameters as benchmark detection data. It also uses a multi-dimensional comparison strategy to identify the causes of defects and generates corresponding adjustment strategies based on these causes.

[0044] The bonding detection module also includes a light group positioned above the composite material, with the length of the light group being the same as the width of the composite material. The bonding detection module is equipped with a dedicated light group installed directly above the composite material, its length matching the width of the composite material. This light group emits uniform and stable light, fully covering the composite material detection area, effectively eliminating ambient light interference and blind spots, clearly revealing the edge contours and bonding status of the protective film and substrate. This provides excellent illumination conditions for the visual inspection device to accurately acquire edge feature images and extract feature points, ensuring the accuracy of bonding angle and deviation parameter detection.

[0045] The above are merely preferred embodiments of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principle of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A method for detecting the film coating on PCM boards, characterized in that, include: The pre-attachment inspection step is used to perform optical inspection on the protective film and the substrate respectively before lamination to obtain pre-attachment parameters. The pre-attachment parameters include the initial uniformity and surface state parameters of the protective film, the initial flatness of the substrate, and the position offset. In the film lamination inspection step, a vision inspection device is set between the protective film and the substrate. The vision inspection device is used to detect the bonding angle between the substrate and the protective film during the bonding process and generate bonding parameters. The post-application inspection step involves optically inspecting the composite after the film has been applied to obtain post-application parameters, including the protective film surface uniformity parameters, the relative positional deviation parameters between the film and the substrate, and the relative angle parameters. The defect analysis and adjustment steps involve obtaining pre-attachment parameters, bonding parameters, and bonding parameters as benchmark detection data, and using a multi-dimensional comparison strategy to identify the causes of defects, and then generating corresponding adjustment strategies based on the causes of defects.

2. The PCM board coating detection method according to claim 1, characterized in that, The optical inspection includes transmission optical inspection and reflection optical inspection. Transmission optical inspection uses a light source to emit a transmitted light beam to perform optical inspection on the protective film. The transmitted light beam is used to collect the transmission spectrum data of the protective film, and the thickness value of the protective film at its spatial position is calculated based on the interference model of the protective film. According to the thickness value of the protective film, the initial uniformity and surface state parameters of the protective film are obtained. Reflection optical inspection uses a light source to emit a reflected light beam and illuminate the substrate surface to collect the reflection image data of the substrate and obtain the reflectivity distribution of the substrate surface. According to the mapping relationship between the reflectivity distribution and the flatness of the substrate, the initial flatness of the substrate is obtained.

3. The PCM board coating detection method according to claim 1, characterized in that, The bonding detection step includes: The image acquisition sub-step acquires an image of the composite as the image to be analyzed, and acquires a first reference line with the edge of the protective film as the reference line and a second reference line with the substrate as the reference line in the image to be analyzed. The deviation acquisition sub-step involves calculating the relative position deviation parameter and the relative angle deviation parameter between the protective film and the substrate, with the first baseline as a reference, to obtain the first position deviation parameter and the first angle deviation parameter. Then, with the second baseline as a reference, the relative position deviation parameter and the relative angle deviation parameter between the protective film and the substrate are calculated to obtain the second position deviation parameter and the second angle deviation parameter. The deviation comparison step compares the first position deviation parameter, the first angle deviation parameter, the second position deviation parameter, and the second angle deviation parameter to obtain the relative position deviation parameter and the relative angle parameter between the film and the substrate.

4. The PCM board coating detection method according to claim 3, characterized in that, It also includes a deviation source acquisition sub-step. If the difference between the first position deviation parameter and the second position deviation parameter is within a first preset threshold range, and the difference between the first angle deviation parameter and the second angle deviation parameter is within a second preset threshold range, then it is determined that the deviation mainly originates from the initial alignment process or upstream process before bonding; otherwise, it is determined that the deviation mainly originates from the action or parameter change of the bonding execution mechanism during the bonding process.

5. The PCM board coating detection method according to claim 1, characterized in that, The causes of the defects include uneven substrate surface, uneven thickness of protective film, deformation caused by film tension deviation, abnormal tension adjustment of the correction device, and deformation caused by pressing. The adjustment strategies include adjusting the tension of the protective film, adjusting the tension of the correction device, and adjusting the pressing force.

6. The PCM board coating detection method according to claim 1, characterized in that, The film-attachment detection step includes: before attachment, acquiring edge feature images of the protective film and the substrate, extracting the intersection of the edges of the protective film and the substrate as feature points, and obtaining the theoretical fixed angle; during attachment, simultaneously acquiring edge feature images of the protective film and the substrate, obtaining the spatial attachment angle, and after correcting the feature points according to the vibration correction compensation model, obtaining the relative attachment angle; comparing the relative attachment angle with the theoretical fixed angle, and if the difference exceeds the set tolerance, the relative attachment angle is determined to be abnormal.

7. The PCM board coating detection method according to claim 1, characterized in that, The multi-dimensional comparison strategy includes comparing the initial uniformity of the protective film and the surface uniformity parameters of the protective film. If the surface uniformity parameters are unqualified but the initial uniformity is qualified, it is determined that the substrate surface is uneven. The relative angle deviation between the film and the substrate is extracted. Combined with the surface uniformity parameters of the protective film and the relative position deviation parameters between the film and the substrate, the influence of the bonding angle on the bonding effect is analyzed. The initial flatness of the substrate is compared with the relative position deviation parameters between the film and the substrate. If the initial flatness of the substrate is qualified, but the relative position deviation is abnormal, it is determined that the film tension is abnormal or the correction device is abnormal.

8. The PCM board coating detection method according to claim 1, characterized in that, When adjusting the strategy requires modifying the production line and the current batch of products can be discarded, extreme testing steps are performed. These extreme testing steps include extreme adjustments to the tension of the protective film, changing the effective thickness and stress distribution of the protective film, repeating the testing steps under extreme tension, obtaining verification testing data, comparing the verification testing data with the benchmark testing data, and calculating the change in testing accuracy indicators. The testing accuracy includes thickness detection error, defect detection error, edge alignment judgment error, etc. When the change in testing accuracy indicators meets the preset validity threshold, the proposed production line modification scheme is deemed valid, and the determined modification parameters are output.

9. A PCM board coating inspection system, characterized in that, include: The pre-attachment detection module is used to perform optical detection on the protective film and the substrate respectively before lamination to obtain pre-attachment parameters, including the initial uniformity and surface state parameters of the protective film, and the initial flatness and position offset of the substrate. The film bonding detection module has a vision detection device between the protective film and the substrate. The vision detection device is used to detect the bonding angle between the substrate and the protective film during the bonding process and generate bonding parameters. The post-application inspection module performs optical inspection on the composite after the film is applied to obtain post-application parameters, including the protective film surface uniformity parameters, the relative positional deviation parameters between the film and the substrate, and the relative angle parameters. The defect analysis and adjustment module acquires pre-attachment parameters, bonding parameters, and bonding parameters as benchmark detection data. It also uses a multi-dimensional comparison strategy to identify the causes of defects and generates corresponding adjustment strategies based on these causes.

10. The PCM board coating inspection system according to claim 9, characterized in that, The bonding detection module also includes a light group, which is positioned above the composite and has the same length as the width of the composite.

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