A yield calculation method for a polarizing sheet web

Abstract

The application discloses a yield calculation method of polarizing film coiled material, and relates to the technical field of polarizing film coiled material production, and comprises the following steps: S10, collecting first defect information in at least one process of the polarizing film coiled material; S20, selecting part or all of the collected first defect information in the corresponding process, and converting the first defect information into second defect information through a coordinate conversion calculation method, wherein the second defect information comprises the number of defects on each polarizing film sheet in a plurality of polarizing film sheets that can be formed after the polarizing film coiled material is processed. The steps S10 to S30 are sequentially executed in order, the yield determination can be completed immediately after the polarizing film coiled material is offline, the yield of the polarizing film coiled material is calculated through the yield calculation method, so that it is not necessary to wait for the cutting to be completed and then to calculate the yield, the feedback cycle of the yield can be shortened, the process parameters can be quickly adjusted to help the production line, the batch yield loss can be reduced, and the cost control can be realized from the front end of production.

Description

Technical Field

[0001] This invention relates to the field of polarizing film roll production technology, specifically to a method for calculating the yield of polarizing film rolls. Background Technology

[0002] Polarizing films are the core optical components of liquid crystal displays (LCDs). Their function is to convert natural light into linearly polarized light, which, in conjunction with the LCD panel, enables image display. In the face of fierce market competition, polarizing film manufacturers face continuous pressure to lower prices, and the fastest way to save costs is to improve yield. Therefore, polarizing film yield assessment is not only a core aspect of quality control but also leads to cost reduction, efficiency improvement, and enhanced competitiveness.

[0003] Appearance defects are the most significant factor affecting the yield of polarizers. Polarizer manufacturing involves three processes: pre-processing, mid-processing, and post-processing. The pre-processing is the stretching process, where PVA is dyed and stretched, and then laminated with TAC and a protective film. The mid-processing is the coating process, where pressure-sensitive adhesive is applied to the stretched semi-finished roll and then laminated with a release film. The post-processing is the cutting of the polarizer roll. Determining the yield of the post-processing cutting is relatively simple; just classify the qualified and unqualified sheets to calculate the yield of the corresponding batch. However, since roll production precedes sheet production, if the yield of the roll produced during the stretching and coating process is not known in a timely and accurate manner, it will result in yield losses, affecting quality and cost. The stretching and coating processes are the core links in polarizer manufacturing. Polarizers are presented in roll form, and the stretching and coating processes are respectively used in conjunction with automated optical inspection (AOI) equipment to detect appearance defects on the film surface, assisting the production line in understanding the quality of the film surface in real time. However, currently, AOI equipment is not capable of accurately determining the yield of each roll produced. Summary of the Invention

[0004] The present invention aims to solve the problem that existing AOI equipment cannot analyze and judge the yield of problematic polarizers before cutting, which may lead to yield loss after cutting polarizer rolls, affecting quality and cost.

[0005] To address the above problems, this invention provides a method for calculating the yield of polarizing film rolls, comprising the following steps: S10. Collect information on the first defect in at least one process of polarizing film roll material; S20. Select some or all of the first defect information collected in the corresponding process, and convert the first defect information into second defect information through coordinate transformation calculation method. The second defect information includes the number of defects on each polarizing sheet in several polarizing sheets that may be formed after the polarizing sheet roll is processed. S30. Based on the number of defects p that a single sheet can tolerate, analyze the second defect information. If the number of defects on a single polarizing sheet that may be formed is greater than or equal to p, the polarizing sheet is identified as a defective polarizing sheet. Summarize the defect information of all possible polarizing sheets and calculate the yield of the polarizing sheet roll using the yield calculation method.

[0006] The present invention provides a method for calculating the yield of polarizing film rolls, which, compared with the prior art, has the following beneficial effects, but is not limited to: Steps S10 to S30 are executed sequentially. They can be used to calculate the yield of a single process for the extension and coating processes in polarizer production, or to calculate the yield of the entire process for both extension and coating. This allows for immediate yield determination after the polarizer roll comes off the production line. The yield of the polarizer roll is calculated using a yield calculation method, eliminating the need to wait for the subsequent cutting process to complete the yield calculation. This shortens the yield feedback cycle, helps the production line quickly adjust process parameters, reduces batch yield losses, and enables cost control from the front end of production.

[0007] As a further aspect of the present invention: the first defect information includes the coordinate position and size information of the defect on the polarizing film roll, wherein the coordinate position is (x, y), where x is the horizontal coordinate of the defect center and y is the vertical coordinate of the defect center.

[0008] As a further aspect of the present invention: the coordinate transformation calculation method includes and Where α is the unusable length of the polarizing film roll after being cut in the horizontal direction, a is the length of the polarizing film roll in the horizontal direction, b is the length of the polarizing film roll in the vertical direction, and the calculation results of c and d are rounded down, c is the possible position of the polarizing film in the horizontal direction, and d is the possible position of the polarizing film in the vertical direction.

[0009] As a further aspect of the present invention: in step S30, the defect information includes the number N of polarizing sheet materials identified as defective. The initial value of N is 0. When the c and d of m first defect information are the same after being converted by the coordinate transformation calculation method, and m is greater than or equal to p, the value of N is increased by 1 on the original basis. All first defect information is converted by the coordinate transformation calculation method to form the final value of N.

[0010] As a further aspect of the present invention: the yield calculation method is as follows: Where W is the length of the polarizing film roll in the horizontal direction, L is the length of the polarizing film roll in the vertical direction, and N is the final value of the number of polarizing film sheets identified as defective. and The result is rounded down, and Y represents the yield.

[0011] As a further aspect of the present invention: after step S30, step S40 may be included, calculating the number of defects per unit area of ​​the polarizing film roll using a defect percentage calculation method, wherein the defect percentage calculation method is as follows: , where Z is the number of defective polarizing film rolls per unit area.

[0012] As a further aspect of the present invention: step S10 includes simultaneously collecting the first defect information in the extension process and the coating process, removing the duplicate first defect information, and then merging the remaining first defect information to obtain a set of modified first defect information.

[0013] As a further aspect of the present invention: In step S30, when g first defect information is converted to the same c and d by the coordinate transformation calculation method, and g is greater than p, the value of N is increased by 1 on the original basis. When a new first defect information is converted to the same c and d by the coordinate transformation calculation method as the g first defect information, the increase of the value of g is stopped, and the next first defect information is directly calculated.

[0014] As a further aspect of the present invention: Step S10 specifically involves, after collecting first defect information in at least one process of polarizing film roll, sorting the first defect information according to coordinates, first comparing x values, then comparing y values, and sorting in ascending order.

[0015] As a further aspect of the present invention: the first defect information also includes defect types, and in step S20, selecting some or all of the first defect information collected in the corresponding process specifically means selecting some or all of the corresponding defect types. Attached Figure Description

[0016] The invention will now be further described with reference to the accompanying drawings.

[0017] Figure 1 This is a schematic diagram of the web structure of the polarizing film roll in this invention; Figure 2 This is a schematic diagram of the calculation method in this invention. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. It should be understood that the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments described in this application without creative effort will fall within the scope of protection of this application.

[0019] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in the specification of this application is for the purpose of describing specific embodiments only and is not intended to limit this application; the terms "comprising," "including," "having," "containing," etc., in the specification, claims, and accompanying drawings of this application are open-ended terms. Therefore, "comprising," "including," or "having" refers to, for example, a method or apparatus having one or more steps or elements, but is not limited to having only these one or more elements. The terms "first," "second," etc., in the specification, claims, or accompanying drawings of this application are used to distinguish different objects, not to describe a specific order or hierarchy. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.

[0020] In the description of this invention, it should be understood that the terms "upper", "lower", "left", "right", "front", "rear", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0021] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "attachment" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0022] It should be emphasized that when the term "comprising / including" is used in this specification, it is used to clearly indicate the presence of the described features, integers, steps or components, but does not exclude the presence or addition of one or more other features, integers, steps, parts or groups of features, integers, steps, parts.

[0023] In this application, the term "and / or" is merely a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, in this application, the character " / " generally indicates that the associated objects before and after are in an "or" relationship.

[0024] Such as Figure 1 and Figure 2 As shown, a method for calculating the yield of a polarizer roll includes the following steps: S10. Collect the first defect information in at least one process of the polarizer roll; S20. Select some or all of the first defect information collected in the corresponding process, and convert the first defect information into second defect information through a coordinate conversion calculation method. The second defect information includes the number of defects on each polarizer sheet in several polarizer sheets that may be formed after the processing of the polarizer roll; S30. Analyze the second defect information according to the tolerable number of defects p per single sheet. Among them, when the number of defects on a single polarizer sheet that may be formed is greater than or equal to p, it is determined that the polarizer sheet is a defective polarizer sheet. Summarize the defective information of all possible polarizer sheets, and calculate the yield of the polarizer roll through the yield calculation method.

[0025] In this embodiment, the method for calculating the yield of the polarizer roll is executed based on the automatic optical inspection (AOI) equipment and the host computer calculation system supporting the polarizer production line. Steps S10 to S30 are executed sequentially in order. The single-process yield calculation can be carried out for the stretching process and the coating process of the polarizer production respectively, or the overall process yield calculation can be carried out for the stretching and coating processes, realizing the immediate yield determination after the polarizer roll is taken off the production line. Exemplarily: First collect the first defect information in one of the processes, convert the first defect information into second defect information through a coordinate conversion calculation method, and the second defect information can be reflected in the number of defects on each polarizer sheet in several polarizer sheets that may be formed. Then compare the number of defects on each possible polarizer sheet with the tolerable number of defects p per single sheet, judge the possible number of defective polarizer sheets after the subsequent process of cutting, and calculate the yield of the polarizer roll through the yield calculation method. In this way, there is no need to wait until the subsequent process of cutting is completed to count the yield, which can shorten the feedback cycle of the yield, help the production line quickly adjust the process parameters, reduce the batch yield loss, and realize cost control from the front end of production.

[0026] Optionally, the first defect information includes the coordinate position and size information of the defect on the polarizer roll, with the coordinate position being (x, y), where x is the horizontal coordinate of the defect center and y is the vertical coordinate of the defect center.

[0027] In this embodiment, the first defect information can be collected by the AOI equipment of the corresponding process of the polarizer production line using line scanning. The AOI equipment adopts a horizontal (Cd direction) line scanning mode, with the edge of the roll material M as the zero point of the horizontal coordinate x, and the direction of the roll material feed as the extension direction of the vertical coordinate y. For each defect detected, the horizontal coordinate x and vertical coordinate y of the defect center are recorded simultaneously, and the size information such as the size and area of ​​the outer rectangle of the defect is collected. A defect information table is generated according to the detection order. The coordinate position corresponds one-to-one with the physical position of the roll material, ensuring that the target cut material to which the defect belongs can be accurately located after subsequent coordinate transformation, providing accurate positional data support for yield calculation and avoiding distortion of yield calculation results due to coordinate deviation.

[0028] Optionally, coordinate transformation calculation methods include and Where α is the unusable length of the polarizing film roll after being cut in the horizontal direction, a is the length of the polarizing film roll in the horizontal direction, b is the length of the polarizing film roll in the vertical direction, and the calculation results of c and d are rounded down, c is the possible position of the polarizing film in the horizontal direction, and d is the possible position of the polarizing film in the vertical direction.

[0029] In this embodiment, the coordinate transformation calculation method uses a rounding function to round down. Since a decimal indicates that the defect is still within the polarizing sheet material that may be formed after cutting, rounding down ensures that the calculation result matches the actual position of the cut complete sheet material. Here, α is the M-side cutting shielding distance, i.e., the unusable width after cutting the edge of the roll material in the horizontal coordinate direction. For example, in this embodiment, α can be 0.022m; a is the length of a single cut sheet material in the Cd direction (horizontal coordinate direction); b is the length of a single cut sheet material... The length in the Md direction (vertical axis) can be flexibly set according to the finished polarizer size required by downstream customers. In this embodiment, for a 15.6-inch polarizer product, a=0.198m and b=0.345m can be set. Through this coordinate transformation calculation method, the discrete defect coordinates on the roll can be mapped to the grid position of the corresponding single sheet after the roll is cut. Each unique (c,d) value corresponds to a unique finished polarizer sheet, realizing the binding of defects with the sheet to which they belong, and providing a basis for the subsequent defect judgment of single sheets.

[0030] Optionally, in step S30, the defect information includes the number N of polarizing sheet materials identified as defective. The initial value of N is 0. When the c and d of m first defect information are the same after being transformed by the coordinate transformation calculation method, and m is greater than or equal to p, the value of N is increased by 1 on the original basis. All first defect information is transformed by the coordinate transformation calculation method to form the final value of N.

[0031] In this embodiment, the number N of defective sheets can be counted by traversing all first defect information. The traversal order can be in ascending order of the defect coordinate x and y values. Before the traversal begins, the initial value of N is set to 0, and a defect count variable is set for each group (c,d) of sheets with an initial value of 0. During the traversal, after each defect coordinate transformation is completed, the defect count variable of the sheet corresponding to the defect (c,d) is incremented by 1. When the value m of the defect count variable corresponding to a certain group (c,d) is greater than or equal to the number of defects p that a single sheet can tolerate, the sheet is determined to be a defective sheet, and N is incremented by 1. Furthermore, any subsequent defects added to the sheet will not trigger a change in the value of N, thus avoiding duplicate counting of the same defective sheet. Through this statistical method, the total number of defective sheets in all sheets that can be formed after the roll is cut can be counted, ensuring that the basic data for yield calculation is accurate and avoiding yield calculation deviations caused by duplicate counting.

[0032] Optionally, the yield calculation method is as follows: Where W is the length of the polarizing film roll in the horizontal direction, L is the length of the polarizing film roll in the vertical direction, and N is the final value of the number of polarizing film sheets identified as defective. and The result is rounded down, and Y represents the yield.

[0033] In this embodiment, in the yield calculation method, W is the effective width of the polarizing film roll (total length in the horizontal direction), and L is the total length of the polarizing film roll (total length in the vertical direction). In this embodiment, W can be set to 1.43m and L to 1300m. This represents the number of complete sheets that can be cut from the roll material along the horizontal axis. The product of the two values ​​represents the number of complete sheets that can be cut from a single roll of material along its longitudinal axis. By rounding down, invalid areas at the edges of the roll that cannot form complete sheets are eliminated, ensuring that the total number of sheets counted is consistent with the actual production cutting results. The yield rate of a single roll of material can be directly calculated using this formula. The numerical result can intuitively reflect the quality level of the roll and can be directly used for production line quality control and batch determination.

[0034] Optionally, step S30 may be followed by step S40, which involves calculating the number of defects per unit area of ​​the polarizing film roll using a defect percentage calculation method. The defect percentage calculation method is as follows: , where Z is the number of defective polarizing film rolls per unit area.

[0035] In this embodiment, the calculation of the number of defects per unit area Z is performed synchronously after the number of defective sheets N is counted, and the calculation result can be retained to one decimal place; wherein The Z value, calculated using this formula, represents the total area of ​​a single roll of polarizing film. It can characterize the number of defective sheets per square meter of the roll, eliminating the influence of dimensional differences between rolls of different lengths and widths. It can be directly used for horizontal comparison of quality levels between different batches and specifications of rolls.

[0036] Optionally, step S10 includes simultaneously collecting the first defect information in the extension process and the coating process, removing duplicate first defect information, and then merging the remaining first defect information to obtain a set of modified first defect information.

[0037] In this embodiment, the first defect information of the extension process and the coating process can be collected independently by the AOI equipment of the corresponding process. After the collection is completed, duplicate defect matching judgment is performed based on the coordinate position, size information and defect characteristics of the defect. For the same defect in the same physical location, if it is detected by the AOI equipment in both the extension process and the coating process, it is judged as a duplicate defect. When merging defect information, it is only retained once to avoid the same defect being counted repeatedly, which would lead to a low yield calculation result. Through deduplication and merging, a real defect information set of the entire production process of a single roll of material can be obtained. The aggregated yield calculated based on this set can reflect the real quality level of the final finished product of the roll material.

[0038] Optionally, in step S30, when g first defect information is converted to the same c and d by the coordinate transformation calculation method, and g is greater than p, the value of N is increased by 1 on the original basis. When a new first defect information is converted to the same c and d by the coordinate transformation calculation method as the g first defect information, the increase of the value of g is stopped, and the next first defect information is calculated directly.

[0039] In this embodiment, this step is used to optimize the efficiency of defect traversal calculation and avoid invalid calculations in defect-dense areas. When g defects have accumulated at position (c,d) of a single sheet, and the value of g exceeds the number of defects p that a single sheet can tolerate, the sheet has been determined to be a defective sheet. Subsequent new defects falling into this sheet area will no longer undergo the accumulation operation of the g value, and will directly jump to the coordinate transformation and calculation process of the next defect. For example, g can be 10. When the number of repeated comparisons of defects at the same (c,d) position exceeds 10, the area is determined to be a defect-prone area, and the defect counting operation of the sheet is directly terminated, jumping to the calculation process of the next defect. Through this optimization method, the amount of invalid calculations in defect-dense areas can be reduced, the yield calculation time of a single roll of material can be shortened, and the calculation efficiency can be improved.

[0040] Optionally, step S10 specifically involves, after collecting first defect information in at least one process of polarizing film roll, sorting the first defect information according to coordinates, first comparing x values, then comparing y values, and sorting in ascending order.

[0041] In this embodiment, the sorting operation of the first defect information is performed after the defect information is collected and before the coordinate transformation calculation. During sorting, the horizontal coordinate x-values ​​of the defects are sorted from smallest to largest first. For defects with the same x-value, they are then sorted from smallest to largest according to the vertical coordinate y-value, thus forming an ordered list of defect information. This sorting method ensures that the subsequent defect traversal process is carried out in the order of the physical position of the roll material, avoiding errors in sheet defect counting caused by disordered defect information. At the same time, it facilitates the continuous statistical analysis of defects at the same (c,d) position during the calculation process, which is beneficial to further improve the calculation efficiency and the accuracy of the calculation results.

[0042] Optionally, the first defect information also includes defect types. In step S20, selecting some or all of the first defect information collected in the corresponding process specifically means selecting the corresponding part or all of the defect types.

[0043] In this embodiment, the first defect information may include defect type information, such as the defect name, size level, and type attributes. All defect type information can be integrated into a defect type overview table, with check and deselection options for each defect category. In step S20, the operator can flexibly select the defect types that need to be included in the yield calculation according to product quality standards and downstream customer requirements. Unselected defect types will not be included in the subsequent coordinate transformation and defect judgment process. At the same time, by repeatedly selecting different combinations of defect types, the defect information of the same roll of material can be calculated multiple times to generate multiple sets of yield results under different judgment conditions, meeting the yield analysis needs of different scenarios and improving the applicability and flexibility of the method.

[0044] While the present invention has been disclosed above, its scope of protection is not limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention, and all such changes and modifications will fall within the scope of protection of the present invention.

Claims

1. A method for calculating the yield of polarizing film rolls, characterized in that, Includes the following steps: S10. Collect information on the first defect in at least one process of polarizing film roll material; S20. Select some or all of the first defect information collected in the corresponding process, and convert the first defect information into second defect information through coordinate transformation calculation method. The second defect information includes the number of defects on each polarizing sheet in several polarizing sheets that may be formed after the polarizing sheet roll is processed. S30. Based on the number of defects p that a single sheet can tolerate, analyze the second defect information. If the number of defects on a single polarizing sheet that may be formed is greater than or equal to p, the polarizing sheet is identified as a defective polarizing sheet. Summarize the defect information of all possible polarizing sheets and calculate the yield of the polarizing sheet roll using the yield calculation method.

2. The method for calculating the yield of polarizing film rolls according to claim 1, characterized in that, The first defect information includes the coordinate position and size information of the defect on the polarizing film roll, wherein the coordinate position is (x, y), where x is the horizontal coordinate of the defect center and y is the vertical coordinate of the defect center.

3. The method for calculating the yield of polarizing film rolls according to claim 2, characterized in that, The coordinate transformation calculation method includes and Where α is the unusable length of the polarizing film roll after being cut in the horizontal direction, a is the length of the polarizing film roll in the horizontal direction, b is the length of the polarizing film roll in the vertical direction, and the calculation results of c and d are rounded down, c is the possible position of the polarizing film in the horizontal direction, and d is the possible position of the polarizing film in the vertical direction.

4. The method for calculating the yield of polarizing film rolls according to claim 3, characterized in that, In step S30, the defect information includes the number N of polarizing sheet materials identified as defective. The initial value of N is 0. When the c and d of m first defect information are the same after being converted by the coordinate transformation calculation method, and m is greater than or equal to p, the value of N is increased by 1 on the original basis. All first defect information is converted by the coordinate transformation calculation method to form the final value of N.

5. The method for calculating the yield of polarizing film rolls according to claim 4, characterized in that, The yield calculation method is as follows: Where W is the length of the polarizing film roll in the horizontal direction, L is the length of the polarizing film roll in the vertical direction, and N is the final value of the number of polarizing film sheets identified as defective. and The result is rounded down, and Y represents the yield.

6. The method for calculating the yield of polarizing film rolls according to claim 4, characterized in that, The step S30 may further include S40, which involves calculating the number of defects per unit area of ​​the polarizing film roll using a defect percentage calculation method. The defect percentage calculation method is as follows: , where Z is the number of defective polarizing film rolls per unit area.

7. The method for calculating the yield of polarizing film rolls according to claim 1, characterized in that, Step S10 includes simultaneously collecting first defect information from the extension process and the coating process, removing duplicate first defect information, and then merging the remaining first defect information to obtain a set of modified first defect information.

8. The method for calculating the yield of polarizing film rolls according to claim 4, characterized in that, In step S30, when g first defect information is converted to the same c and d by the coordinate transformation calculation method, and g is greater than p, the value of N is increased by 1. When a new first defect information is converted to the same c and d by the coordinate transformation calculation method as the g first defect information, the increase of the value of g is stopped, and the next first defect information is calculated directly.

9. The method for calculating the yield of polarizing film rolls according to claim 1, characterized in that, The S10 step specifically involves collecting first defect information from at least one process of the polarizing film roll, sorting the first defect information according to coordinates, first comparing the x-values, then comparing the y-values, and sorting them in ascending order.

10. The method for calculating the yield of polarizing film rolls according to claim 1, characterized in that, The first defect information also includes defect types. In step S20, selecting some or all of the first defect information collected in the corresponding process specifically means selecting some or all of the corresponding defect types.

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