Method for on-line evaluation of etching uniformity of flexible circuit board

Abstract

The application discloses a flexible circuit board etching uniformity online evaluation method and relates to the technical field of etching uniformity evaluation, which comprises the following steps: obtaining a real-time flexible circuit board image according to the flexible circuit board after etching, and obtaining real-time flexible circuit board grayscale values based on the real-time flexible circuit board image; obtaining a real-time copper body region according to the real-time flexible circuit board grayscale values and real-time grayscale segmentation threshold values; obtaining a real-time corrected copper body region according to the real-time copper body region, and obtaining a real-time corrected copper body edge according to the real-time corrected copper body region; constructing a second real-time evaluation value according to the real-time corrected copper body edge; obtaining a historical flexible circuit board image according to the flexible circuit board with qualified etching uniformity, and obtaining a historical normal evaluation threshold value according to the historical flexible circuit board image; and the application is used to solve the problem that no suitable method is set for etching uniformity detection of etching copper line edges in the prior art, thereby causing the problem that flexible circuit board etching uniformity evaluation is not comprehensive.

Description

Technical Field

[0001] This invention relates to the field of etching uniformity evaluation technology, specifically to an online evaluation method for etching uniformity of flexible printed circuit boards. Background Technology

[0002] Etching of flexible circuit boards is a process in which unwanted copper layers are removed from copper-clad laminates using a specific etching solution to form fine circuit patterns. If the etching uniformity is not up to standard, it can lead to over-etching or under-etching, which will affect electrical performance and even cause the flexible circuit board to be scrapped. Therefore, it is necessary to evaluate the etching uniformity of flexible circuit boards.

[0003] In the etching of flexible circuit boards, if the etching uniformity of the copper wire edges is not up to standard, it will affect the electrical performance. Furthermore, the flexible circuit board is prone to micro-cracks or wire breaks when bent, rendering it unusable. Existing flexible circuit board etching uniformity assessments mainly focus on the uniformity of the etched copper residual thickness and etching rate, without establishing a specific method for detecting the etching uniformity of the copper wire edges. In other words, existing technologies do not have a suitable method for detecting the etching uniformity of the copper wire edges, resulting in an incomplete assessment of the etching uniformity of flexible circuit boards. Summary of the Invention

[0004] The present invention aims to at least partially solve one of the technical problems in the prior art, namely, the lack of a suitable method for detecting the etching uniformity of etched copper lines in the prior art, which leads to an incomplete evaluation of the etching uniformity of flexible circuit boards.

[0005] To achieve the above objectives, in a first aspect, this application provides an online evaluation method for the etching uniformity of flexible printed circuit boards, comprising the following steps: S100: Obtain a real-time flexible circuit board image based on the etched flexible circuit board; obtain the real-time grayscale value of the flexible circuit board based on the real-time flexible circuit board image; obtain a real-time grayscale segmentation threshold based on the real-time grayscale value of the flexible circuit board; obtain the real-time copper body region based on the real-time flexible circuit board grayscale value and the real-time grayscale segmentation threshold. S200: Obtain the real-time corrected copper body region based on the real-time copper body region; obtain the real-time corrected copper body edge based on the real-time corrected copper body region; construct the second real-time evaluation value based on the real-time corrected copper body edge. S300: Obtain historical flexible circuit board images based on flexible circuit boards with qualified etching uniformity, and obtain historical normal evaluation thresholds based on historical flexible circuit board images. S400 determines whether the etching uniformity of the flexible circuit board is qualified based on the second real-time evaluation value and the historical normal evaluation threshold.

[0006] Furthermore, step S100 also includes the following sub-steps: The etched flexible circuit board is laid flat on a white matte background board, and then an image of the flexible circuit board is obtained and labeled as a real-time flexible circuit board image. The real-time flexible circuit board diagram is converted to grayscale to obtain a grayscale image, which is then identified as the real-time flexible circuit board grayscale image. Each pixel in the grayscale image of the real-time flexible circuit board is identified as a pixel of the real-time flexible circuit board. Obtain the grayscale value of each pixel on the real-time flexible circuit board and identify it as the grayscale value of the real-time flexible circuit board.

[0007] Furthermore, step S100 also includes the following sub-steps: Define a number of divisions for the grayscale value range from 0 to 255, and label it as the first division number; divide the grayscale value range from 0 to 255 into ranges of equal length, and label them as the first division range; Obtain the median value of the first division range and mark it as the first median value; Sort the first division range from left to right according to the first median value, from smallest to largest; Obtain the number of real-time grayscale values ​​of flexible circuit boards within each first division range, and identify them as the first division number; The first division range corresponding to the first division quantity that is simultaneously greater than the first division quantity on both the left and right sides is marked as the first filtering range; if there is no first filtering range on one side, the first division quantity on the side without the first filtering range is considered to be 0. Get the median value of the second filter range and mark it as the second median value; Sort the second filtering range from left to right according to the second median value from smallest to largest; then starting from the leftmost second filtering range, obtain the first second filtering range and the second second filtering range from left to right, and label them as the second filtering range and the third filtering range respectively. Obtain the first dividing range between the second and third filtering ranges, and mark it as the fourth filtering range; The fourth filtering range with the smallest number of first divisions is identified as the fifth filtering range. Obtain the median value of the fifth filtering range and mark it as the real-time grayscale segmentation threshold.

[0008] Furthermore, step S100 also includes the following sub-steps: Real-time flexible circuit board grayscale values ​​that are less than the real-time grayscale segmentation threshold are identified as real-time copper body grayscale values. Pixels that acquire the real-time grayscale value of the copper body are identified as real-time copper body pixels. The continuous area composed of real-time copper body pixels is identified as the real-time copper body region.

[0009] Furthermore, step S200 also includes the following sub-steps: Establish a Cartesian coordinate system, labeled as the first coordinate system; place the real-time copper body region in the first quadrant of the first coordinate system; Obtain the minimum and maximum values ​​of the horizontal coordinate in the real-time copper body region, and label them as the first horizontal axis value and the second horizontal axis value, respectively; Obtain the minimum and maximum values ​​of the vertical coordinates in the real-time copper body region, and label them as the first vertical axis value and the second vertical axis value, respectively; Get the difference between the second horizontal axis value and the first horizontal axis value, and label it as the first difference; Obtain the difference between the second vertical axis value and the first vertical axis value, and label it as the second difference; Obtain the product between the first difference and the second difference, and mark it as the real-time correction reference value; By rotating the real-time copper body area and then re-acquiring the real-time correction reference value, when the second difference is greater than the first difference and the real-time correction reference value is at its minimum, the position of the real-time copper body area in the first coordinate system is obtained and marked as the first identification position. The real-time copper area at the first identification position is marked as the real-time corrected copper area; Obtain the outline of each real-time corrected copper body and identify it as the real-time corrected copper body outline; Obtain the two edges with the smallest angle to the vertical axis of the first coordinate system in each real-time corrected copper body contour, and mark them as real-time corrected copper body edges.

[0010] Furthermore, step S200 also includes the following sub-steps: Obtain the first number of uniformly distributed coordinate points on any real-time corrected copper edge, and mark them as real-time copper edge points; The formula for real-time edge fitting is defined as: X = b; where X is the horizontal axis value of the real-time edge fitting formula, and b is the constant of the real-time edge fitting function. The function obtained by fitting the real-time copper edge points with the formula for real-time edge fitting is marked as the real-time edge fitting line. Obtain the distance from each real-time copper edge point to the real-time edge fitted line, and mark it as the first real-time evaluation value; Obtain the average of the first real-time evaluation value and label it as the second real-time evaluation value; Obtain the second real-time evaluation value for each real-time corrected copper body edge.

[0011] Furthermore, step S300 also includes the following sub-steps: A flexible circuit board with acceptable etching uniformity is laid flat on a white matte background board, and then an image of this flexible circuit board area is obtained and marked as a historical flexible circuit board image. Then, the historical flexible circuit board diagram is treated as a real-time flexible circuit board diagram to obtain the real-time corrected copper body edge and the corresponding second real-time evaluation value, which are respectively identified as the historical corrected copper body edge and the second historical evaluation value. Obtain a second number of second historical evaluation values; then obtain the maximum value of the second historical evaluation values ​​and mark it as the historical normal evaluation threshold.

[0012] Furthermore, step S400 also includes the following sub-steps: Determine whether all second real-time evaluation values ​​are less than or equal to the historical normal evaluation threshold. If so, the etching uniformity of the flexible circuit board is considered to be qualified; otherwise, the etching uniformity of the flexible circuit board is considered to be unqualified.

[0013] A second aspect of the present invention provides an electronic device comprising: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores a computer program executable by the at least one processor, the computer program being executed by the at least one processor to enable the at least one processor to perform the method described in the first aspect above.

[0014] A third aspect of the present invention provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the method described in the first aspect above.

[0015] The beneficial effects of this invention are as follows: 1. By obtaining a real-time flexible circuit board image based on the etched flexible circuit board, and obtaining the real-time grayscale value of the flexible circuit board based on the real-time flexible circuit board image; obtaining a real-time grayscale segmentation threshold based on the real-time grayscale value of the flexible circuit board; obtaining a real-time copper body region based on the real-time flexible circuit board grayscale value and the real-time grayscale segmentation threshold; obtaining a real-time corrected copper body region based on the real-time copper body region; obtaining a real-time corrected copper body edge based on the real-time corrected copper body region; constructing a second real-time evaluation value based on the real-time corrected copper body edge; obtaining a historical flexible circuit board image based on a flexible circuit board with qualified etching uniformity, and obtaining a historical normal evaluation threshold based on the historical flexible circuit board image; and judging whether the etching uniformity of the flexible circuit board is qualified based on the second real-time evaluation value and the historical normal evaluation threshold. The advantage is that an accurate and fast method is set for the etching uniformity detection of the etched copper line edge, making the etching uniformity evaluation of the flexible circuit board more comprehensive. 2. Obtain the real-time corrected copper body edge based on the real-time corrected copper body area; construct a second real-time evaluation value based on the real-time corrected copper body edge. The advantage is that the etching uniformity of the copper line edge of the flexible circuit board can be detected by the second real-time evaluation value, and the etching uniformity evaluation of the flexible circuit board is more comprehensive. Attached Figure Description

[0016] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0017] Figure 1 This is a flowchart illustrating the steps of the method of the present invention; Figure 2 This is a schematic diagram illustrating the real-time correction of the copper body contour according to the present invention; Figure 3 This is a schematic diagram illustrating the real-time correction of copper body edges, real-time fitting of straight lines, and real-time copper edge points of the present invention. Detailed Implementation

[0018] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. 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 should fall within the scope of protection of the present invention.

[0019] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be used interchangeably where appropriate so that the embodiments of the invention described herein can cover implementations in sequences other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0020] For the uniformity assessment of flexible printed circuit boards (FPCBs) where the copper traces are straight during flattening, this application does not address the etching uniformity testing of the copper trace edges. To solve this problem, this application provides an online evaluation method for the etching uniformity of flexible printed circuit boards. Please refer to [link to relevant documentation]. Figure 1 As shown, in step S100, a real-time flexible circuit board image is obtained based on the etched flexible circuit board; the real-time grayscale value of the flexible circuit board is obtained based on the real-time flexible circuit board image; a real-time grayscale segmentation threshold is obtained based on the real-time flexible circuit board grayscale value; and the real-time copper body region is obtained based on the real-time flexible circuit board grayscale value and the real-time grayscale segmentation threshold. Step S100 also includes the following steps: Step S101: Lay the etched flexible circuit board flat on a white matte background board, and then obtain an image of the flexible circuit board, which is marked as a real-time flexible circuit board image; the copper lines are straight lines of the flexible circuit board. Step S102: The real-time flexible circuit board diagram is converted to grayscale to obtain a grayscale image, which is then identified as the real-time flexible circuit board grayscale image. Step S103: Mark each pixel in the grayscale image of the real-time flexible circuit board as a pixel of the real-time flexible circuit board. Step S104: Obtain the grayscale value of each real-time flexible circuit board pixel and identify it as the real-time flexible circuit board grayscale value.

[0021] Step S105: Set a number of divisions for the grayscale value range of 0 to 255, and mark it as the first division number; divide the grayscale value range of 0 to 255 into ranges of equal length, and mark them as the first division range; obtain the first division range in order to observe the distribution of grayscale values ​​of the flexible circuit board in real time; therefore, the first division number should not be too small, for example, the first division number is 8; Step S106: Obtain the median value of the first division range and mark it as the first median value; Step S107: Sort the first division range from left to right according to the first median value from smallest to largest; Step S108: Obtain the number of real-time flexible circuit board grayscale values ​​within each first division range, and mark it as the first division number; the distribution of real-time flexible circuit board grayscale values ​​can be determined by the first division number. Step S109: The first division range corresponding to the first division quantity that is greater than both the left and right first division quantities is marked as the first filtering range; if there is no first filtering range on one side, the first division quantity on the side without the first filtering range is determined to be 0; the first filtering range is the range with a large number of gray values. Step S110: Obtain the median value of the second filtering range and mark it as the second median value; Step S111: Sort the second filtering range from left to right according to the second median value from smallest to largest; then, starting from the leftmost second filtering range, obtain the first and second second filtering ranges from left to right, and label them as the second filtering range and the third filtering range respectively; because the background is white, the gray value of the copper line is less than the gray value of the non-copper line of the flexible circuit board, and the gray value of the non-copper line of the flexible circuit board is less than the gray value of the background. The real-time flexible circuit board image only contains these three types of gray values. Therefore, according to the distribution relationship, the second filtering range is mainly the gray value range of the copper body area, and the third filtering range is mainly the gray value range of the non-copper area of ​​the real-time flexible circuit board. Step S112: Obtain the first dividing range between the second and third filtering ranges, and mark it as the fourth filtering range; Step S113: Obtain the fourth filtering range with the smallest number of first divisions and mark it as the fifth filtering range; in order to obtain the grayscale segmentation threshold between copper and non-copper bodies; Step S114: Obtain the median value of the fifth filtering range and mark it as the real-time grayscale segmentation threshold; the real-time grayscale segmentation threshold is the grayscale segmentation threshold between copper and non-copper bodies. In practical applications, the range 0 to 255 is divided into eight equal ranges, for example, a first segmentation range of 0 to 31; the second filtering range is 64 to 95, and the third filtering range is 160 to 191. The first segmentation range between 64 to 95 and 160 to 191 is then identified as the fourth filtering range; the fourth filtering range with the smallest number of first segments is 128 to 159; the fifth filtering range is 128 to 159. The median value of the fifth filtering range 128 to 159 is 143. The obtained value is kept as an integer, so the real-time grayscale segmentation threshold is 143.

[0022] Step S115: Mark the real-time flexible circuit board grayscale values ​​that are less than the real-time grayscale segmentation threshold as real-time copper body grayscale values; because the grayscale values ​​of the copper body region are the smallest. Step S116: Obtain the pixels with real-time copper body grayscale values ​​and mark them as real-time copper body pixels; Step S117: The continuous area composed of real-time copper body pixels is identified as the real-time copper body region; the real-time copper body region is the copper body region in the obtained flexible circuit board. In practical applications, real-time flexible circuit board grayscale values ​​less than 143 are identified as real-time copper body grayscale values.

[0023] Step S200: Obtain the real-time corrected copper body region based on the real-time copper body region; obtain the real-time corrected copper body edge based on the real-time corrected copper body region; construct the second real-time evaluation value based on the real-time corrected copper body edge; Step S200 also includes the following steps: Step S201: Establish a Cartesian coordinate system, labeled as the first coordinate system; place the real-time copper body region in the first quadrant of the first coordinate system; this facilitates the analysis of the real-time copper body region. Step S202: Obtain the minimum and maximum values ​​of the horizontal coordinates in the real-time copper body region, and label them as the first horizontal axis value and the second horizontal axis value, respectively; Step S203: Obtain the minimum and maximum values ​​of the vertical coordinates in the real-time copper body region, and label them as the first vertical axis value and the second vertical axis value, respectively; Step S204: Obtain the difference between the second horizontal axis value and the first horizontal axis value, and mark it as the first difference; Step S205: Obtain the difference between the second vertical axis value and the first vertical axis value, and label it as the second difference; Step S206: Obtain the product between the first difference and the second difference, and mark it as the real-time correction reference value; the real-time correction reference value is the area of ​​the circumscribed rectangle, so the copper wire area is distributed in a rectangle. Therefore, when the real-time correction reference value is the smallest, the real-time correction reference value is exactly the area of ​​the smallest circumscribed rectangle. At this time, the edge of the flexible circuit board is parallel to the axis of the first coordinate system. Step S207: By rotating the real-time copper body area, the real-time correction reference value is re-acquired. When the second difference is greater than the first difference and the real-time correction reference value is at its minimum, the position of the real-time copper body area in the first coordinate system is obtained and marked as the first identification position. Because the copper line area appears as a long strip in the image, in order to make the long side of the long strip parallel to the vertical axis of the first coordinate system under ideal conditions, it is convenient to analyze whether the copper edge of the flexible circuit board is normal in subsequent analysis. Step S208: The real-time copper body area at the first identification position is marked as the real-time corrected copper body area. Step S209: Obtain the outline of each real-time corrected copper body and mark it as the real-time corrected copper body outline; For practical applications, please refer to Figure 2 The diagram shown illustrates the process of obtaining real-time corrected copper body contours.

[0024] Step S210: Obtain the two sides with the smallest angle to the vertical axis of the first coordinate system in each real-time corrected copper body contour, and mark them as real-time corrected copper body sides; the real-time corrected copper body sides are the long sides of the copper body.

[0025] Step S211: Obtain a first number of uniformly distributed coordinate points on any real-time corrected copper body edge, and mark them as real-time copper edge points. Step S212: Set the formula for real-time edge fitting as: X=b; where X is the horizontal axis value of the real-time edge fitting formula, and b is the constant of the real-time edge fitting function; ideally, the copper body edge is corrected to be parallel to the vertical axis of the first coordinate system in real time. Step S213: Fit the real-time copper edge points with the formula for real-time edge fitting to obtain a function, and mark it as the real-time edge fitting line. For practical applications, please refer to Figure 3 The diagram shows a real-time corrected copper edge, a real-time fitted straight line, and a set of real-time copper edge points.

[0026] Step S214: Obtain the distance from each real-time copper edge point to the real-time edge fitting line, and mark it as the first real-time evaluation value; if the copper edge at the real-time copper edge point position is uniform, the first real-time evaluation value is 0; if the uniformity of the copper edge at the real-time copper edge point position is poor, the first real-time evaluation value is larger. Step S215: Obtain the mean of the first real-time evaluation value and mark it as the second real-time evaluation value; the second real-time evaluation value represents the uniformity of a long side of this copper body. Step S216: Obtain the second real-time evaluation value for each real-time corrected copper body edge; For practical applications, please refer to Figure 2 As shown, the second real-time evaluation value obtained is 0.

[0027] Step S300: Obtain historical flexible circuit board images based on flexible circuit boards with acceptable etching uniformity; obtain historical normal evaluation thresholds based on historical flexible circuit board images; Step S300 also includes the following steps: Step S301: Lay the flexible circuit board with qualified etching uniformity flat on a white matte background board, and then obtain an image of this flexible circuit board area, which is marked as a historical flexible circuit board image. Step S302: Then, treat the historical flexible circuit board diagram as the real-time flexible circuit board diagram to obtain the real-time corrected copper body edge and the corresponding second real-time evaluation value, which are respectively identified as the historical corrected copper body edge and the second historical evaluation value. Step S303: Obtain a second number of second historical evaluation values; then obtain the maximum value of the second historical evaluation values ​​and mark it as the historical normal evaluation threshold; this facilitates obtaining the range of second real-time evaluation values ​​with normal uniformity; therefore, the second number should not be too small, for example, the second number is 1000; the historical normal evaluation threshold is obtained as 0.01 mm. Step S400: Determine whether the etching uniformity of the flexible circuit board is qualified based on the second real-time evaluation value and the historical normal evaluation threshold; Step S400 also includes the following step: Step S401: Determine whether all second real-time evaluation values ​​are less than or equal to the historical normal evaluation threshold. If yes, the etching uniformity of the flexible circuit board is considered to be qualified; otherwise, the etching uniformity of the flexible circuit board is considered to be unqualified. Qualified etching uniformity of the flexible circuit board means that the copper edge uniformity is qualified. In practical applications, for example, if a second real-time evaluation value of 0mm is less than the historical normal evaluation threshold of 0.01mm, then the uniformity of this copper edge is considered normal. When all second real-time evaluation values ​​are less than or equal to the historical normal evaluation threshold, the uniformity of this flexible circuit board is considered qualified.

[0028] This application provides an electronic device. The electronic device may include a processor and a memory communicatively connected to the processor. The memory stores computer-executable instructions; the processor executes the computer-executable instructions stored in the memory to implement the method embodiment as described in Embodiment 1 above. The specific implementation and technical effects are similar and will not be repeated here.

[0029] In this embodiment, the memory and processor are connected via a bus. The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus, etc. The bus can be categorized into address bus, data bus, control bus, etc.

[0030] In the above embodiments, it should be understood that the processor can be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), etc. The general-purpose processor can be a microprocessor or any conventional processor. The steps of the method disclosed in this invention can be directly implemented by a hardware processor, or implemented by a combination of hardware and software modules within the processor.

[0031] The memory may include random access memory (RAM) and may also include non-volatile memory (NVM), such as at least one disk storage device.

[0032] The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus, etc. Buses can be categorized as address buses, data buses, control buses, etc. For ease of illustration, the buses shown in the accompanying drawings are not limited to a single bus or a single type of bus.

[0033] This application also provides a computer program product, including a computer program that, when executed by a processor, implements the above-described method.

[0034] This application also provides a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, implement the above-described method.

[0035] The aforementioned readable storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic storage, flash memory, magnetic disk, or optical disk. The readable storage medium can be any available medium accessible to a general-purpose or special-purpose computer.

[0036] An exemplary readable storage medium is coupled to a processor, enabling the processor to read information from and write information to the readable storage medium. Of course, the readable storage medium can also be a component of the processor. The processor and the readable storage medium can reside in an Application Specific Integrated Circuit (ASIC). Alternatively, the processor and the readable storage medium can exist as discrete components in the device.

[0037] Those skilled in the art will understand that all or part of the steps of the above-described method embodiments can be implemented by hardware related to program instructions. The aforementioned program can be stored in a computer-readable storage medium. When executed, the program performs the steps of the above-described method embodiments; and the aforementioned storage medium includes various media capable of storing program code, such as ROM, RAM, magnetic disks, or optical disks.

[0038] Finally, it should be noted that other embodiments of the invention will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This invention is intended to cover any variations, uses, or adaptations of the invention that follow the general principles of the invention and include common knowledge or customary techniques in the art not disclosed herein, and is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of the invention is limited only by the appended claims.

Claims

1. An online evaluation method for etching uniformity of flexible circuit boards, characterized in that, Includes the following steps: S100: Obtain a real-time flexible circuit board image based on the etched flexible circuit board, obtain the real-time grayscale value of the flexible circuit board based on the real-time flexible circuit board image, and obtain the real-time grayscale segmentation threshold based on the real-time grayscale value of the flexible circuit board. The real-time copper body region is obtained based on the real-time grayscale value of the flexible circuit board and the real-time grayscale segmentation threshold. S200: Obtain the real-time corrected copper body region based on the real-time copper body region; obtain the real-time corrected copper body edge based on the real-time corrected copper body region; construct the second real-time evaluation value based on the real-time corrected copper body edge. S300: Obtain historical flexible circuit board images based on flexible circuit boards with qualified etching uniformity, and obtain historical normal evaluation thresholds based on historical flexible circuit board images. S400, based on the second real-time evaluation value and the historical normal evaluation threshold, determines whether the etching uniformity of the flexible circuit board is qualified. The S200 step also includes the following sub-steps: Establish a Cartesian coordinate system, labeled as the first coordinate system; place the real-time copper body region in the first quadrant of the first coordinate system; Obtain the minimum and maximum values ​​of the horizontal coordinate in the real-time copper body region, and label them as the first horizontal axis value and the second horizontal axis value, respectively; Obtain the minimum and maximum values ​​of the vertical coordinates in the real-time copper body region, and label them as the first vertical axis value and the second vertical axis value, respectively; Get the difference between the second horizontal axis value and the first horizontal axis value, and label it as the first difference; Obtain the difference between the second vertical axis value and the first vertical axis value, and label it as the second difference; Obtain the product between the first difference and the second difference, and mark it as the real-time correction reference value; By rotating the real-time copper body area and then re-acquiring the real-time correction reference value, when the second difference is greater than the first difference and the real-time correction reference value is at its minimum, the position of the real-time copper body area in the first coordinate system is obtained and marked as the first identification position. The real-time copper area at the first identification position is marked as the real-time corrected copper area; Obtain the outline of each real-time corrected copper body region and label it as the real-time corrected copper body outline; Obtain the two edges with the smallest angle to the vertical axis of the first coordinate system in each real-time corrected copper body contour, and mark them as real-time corrected copper body edges.

2. The method according to claim 1, characterized in that, The S100 step also includes the following sub-steps: The etched flexible circuit board is laid flat on a white matte background board, and then an image of the flexible circuit board is obtained and labeled as a real-time flexible circuit board image. The real-time flexible circuit board diagram is converted to grayscale to obtain a grayscale image, which is then identified as the real-time flexible circuit board grayscale image. Each pixel in the grayscale image of the real-time flexible circuit board is identified as a pixel of the real-time flexible circuit board. Obtain the grayscale value of each pixel on the real-time flexible circuit board and identify it as the grayscale value of the real-time flexible circuit board.

3. The method according to claim 2, characterized in that, The S100 step also includes the following sub-steps: Define the number of divisions for the grayscale value range from 0 to 255, and label it as the number of the first division range; divide the grayscale value range from 0 to 255 into ranges of equal length, and label them as the first division range; Obtain the median value of the first division range and mark it as the first median value; Sort the first division range from left to right according to the first median value, from smallest to largest; Obtain the number of real-time grayscale values ​​of flexible circuit boards within each first division range, and identify them as the first division number; The first division range corresponding to the first division quantity that is simultaneously greater than the first division quantity on both the left and right sides is marked as the first filtering range; if there is no first filtering range on one side, the first division quantity on the side without the first filtering range is considered to be 0. Get the median value of the first filtering range and mark it as the second median value; Sort the first filtering range from left to right according to the second median value, from smallest to largest; Then, starting from the leftmost first filter range, obtain the first first filter range and the second first filter range from left to right, and label them as the second filter range and the third filter range respectively; Obtain the first dividing range between the second and third filtering ranges, and mark it as the fourth filtering range; The fourth filtering range with the smallest number of first divisions is identified as the fifth filtering range. Obtain the median value of the fifth filtering range and mark it as the real-time grayscale segmentation threshold.

4. The method according to claim 3, characterized in that, The S100 step also includes the following sub-steps: Real-time flexible circuit board grayscale values ​​that are less than the real-time grayscale segmentation threshold are identified as real-time copper body grayscale values. Pixels that acquire the real-time grayscale value of the copper body are identified as real-time copper body pixels. The continuous area composed of real-time copper body pixels is identified as the real-time copper body region.

5. The method according to claim 4, characterized in that, The S200 step also includes the following sub-steps: Obtain the first number of uniformly distributed coordinate points on any real-time corrected copper edge, and mark them as real-time copper edge points; The formula for real-time edge fitting is defined as: X = b; where X is the horizontal axis value of the real-time edge fitting formula, and b is the constant of the real-time edge fitting function. The function is obtained by fitting the real-time copper edge points with the formula for real-time edge fitting, and is marked as the real-time edge fitting line. Obtain the distance from each real-time copper edge point to the real-time edge fitted line, and mark it as the first real-time evaluation value; Obtain the average of the first real-time evaluation value and label it as the second real-time evaluation value; Obtain the second real-time evaluation value for each real-time corrected copper body edge.

6. The method according to claim 5, characterized in that, The S300 step also includes the following sub-steps: A flexible circuit board with acceptable etching uniformity is laid flat on a white matte background board, and then an image of this flexible circuit board area is obtained and marked as a historical flexible circuit board image. Then, the historical flexible circuit board diagram is treated as a real-time flexible circuit board diagram to obtain the real-time corrected copper body edge and the corresponding second real-time evaluation value, which are respectively identified as the historical corrected copper body edge and the second historical evaluation value. Obtain a second number of second historical evaluation values; then obtain the maximum value of the second historical evaluation values ​​and mark it as the historical normal evaluation threshold.

7. The method according to claim 6, characterized in that, The S400 step also includes the following sub-steps: Determine whether all second real-time evaluation values ​​are less than or equal to the historical normal evaluation threshold. If so, the etching uniformity of the flexible circuit board is considered to be qualified; otherwise, the etching uniformity of the flexible circuit board is considered to be unqualified.

8. An electronic device, characterized in that, The electronic device includes: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores a computer program executable by the at least one processor, the computer program being executed by the at least one processor to enable the at least one processor to perform the method as described in any one of claims 1-7.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, implements the method as described in any one of claims 1-7.

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