Angle testing method, system, and film material cutting method

Abstract

An angle testing method, system, and film cutting method. The angle testing method is used to test the ridge line angle of a cut lens film, and the method comprises: sending display data to a display device to cause the display device to display a set of straight lines, and each straight line in the set of straight lines corresponds to an angle; collecting a straight line image displayed through the lens film to be tested, performing image detection on the straight line image, and finding a straight line with the same ridge line angle as the lens film to be tested, and the angle of the straight line is the ridge line angle of the lens film to be tested. The ridge line angle testing method and system of the embodiment can obtain more accurate ridge line angles, thereby ensuring the cutting accuracy of the subsequent film.

Description

Technical Field

[0001] This article relates to the field of display technology, and in particular to an angle testing method, system, and film cutting method. Background Technology

[0002] To achieve stereoscopic and dual-view display, lenticular lens film needs to be laminated to the display side of the display panel. Therefore, the lens film needs to be cut with high precision. In particular, OLED-based stereoscopic and dual-view display products have higher requirements for lamination precision. Otherwise, rainbow patterns or moiré patterns will appear. However, the current film cutting precision is about ±0.2°, which cannot meet the high precision requirements of the lens grating film. Summary of the Invention

[0003] This application provides an angle testing method, system, and membrane material cutting method, which can ensure the cutting accuracy of the membrane material.

[0004] On one hand, this disclosure provides an angle testing method for testing the ridge angle of a cut lens film material, the method comprising: Send display data to the display device so that the display device displays a set of straight lines, and each straight line in the set of straight lines corresponds to an angle; A straight line image is acquired through the lens film material under test. Image detection is performed on the straight line image to find a straight line with the same edge angle as the lens film material under test. The angle of the straight line is the edge angle of the lens film material under test.

[0005] In an exemplary embodiment, the angle range of the set of straight lines is the designed edge angle ± a preset accuracy angle, where the designed edge angle is the expected edge tilt angle and the preset accuracy angle is the allowable error angle.

[0006] In an exemplary embodiment, the step of performing image detection on the straight line image to find a straight line with the same edge angle as the lens film material under test, wherein the angle of the straight line is the edge angle of the lens film material under test, includes: calculating the contrast of each straight line in the straight line image, comparing the contrast of all straight lines, and taking the straight line with the lowest contrast as the straight line with the same edge angle as the lens film material under test, wherein the angle of the straight line is the edge angle of the lens film material under test; or, calculating the contrast of each straight line in the straight line image, comparing the contrast of all straight lines, finding the two straight lines with the lowest contrast, and taking the average of the angles of the two straight lines as the edge angle of the lens film material under test.

[0007] In an exemplary embodiment, calculating the contrast of each straight line in the straight line image includes: calculating the ratio of the maximum grayscale value to the minimum grayscale value at the center line of each straight line as the contrast of the straight line.

[0008] In an exemplary embodiment, before calculating the contrast of each line in the line image, the method further includes: using an edge detection algorithm to identify the edges of each line in the line image.

[0009] In an exemplary embodiment, the set of straight lines are arranged at intervals according to angle values, and the number of straight lines is 2 * preset precision angle / unit precision.

[0010] On the other hand, this disclosure also provides a method for cutting film materials, applicable to the cutting of lens film materials, the method comprising: Set the cutting position and cut the lens film material; If the current lens film is the first lens film in this batch, perform the first film angle test to obtain the actual edge angle of the first lens film. Determine whether the difference between the actual edge angle and the designed edge angle is less than or equal to the first angle threshold. If yes, continue cutting the lens film. If no, reset the cutting position and repeat the cutting of the lens film and the first film angle test. If the current lens film material is not the first lens film material, perform a non-first film material angle test to obtain the actual edge angle of the non-first lens film material. Determine whether the difference between the actual edge angle and the designed edge angle is less than or equal to the second angle threshold. If yes, continue cutting the lens film material. If no, reset the cutting position and perform lens film cutting and non-first film material angle tests. The first angle threshold is less than the second angle threshold.

[0011] In an exemplary embodiment, the non-first-piece angle testing method may be the same as or different from the first-piece angle testing method.

[0012] In an exemplary embodiment, the first-piece angle testing method includes: sending display data to a display device to display a set of straight lines, each of the straight lines corresponding to an angle; acquiring an image of the straight lines displayed through the lens film to be tested; performing image detection on the straight line image to find a straight line with the same edge angle as the lens film to be tested, wherein the angle of the straight line is the edge angle of the lens film to be tested.

[0013] In an exemplary embodiment, the step of performing image detection on the straight line image to find a straight line with the same edge angle as the lens film material under test, wherein the angle of the straight line is the edge angle of the lens film material under test, includes: calculating the contrast of each straight line in the straight line image, comparing the contrast of all straight lines, and taking the straight line with the lowest contrast as the straight line with the same edge angle as the lens film material under test, wherein the angle of the straight line is the edge angle of the lens film material under test; or, calculating the contrast of each straight line in the straight line image, comparing the contrast of all straight lines, finding the two straight lines with the lowest contrast, and taking the average of the angles of the two straight lines as the edge angle of the lens film material under test.

[0014] In an exemplary embodiment, calculating the contrast of each straight line in the straight line image includes: calculating the ratio of the maximum grayscale value to the minimum grayscale value at the center line of each straight line as the contrast of the straight line.

[0015] In an exemplary embodiment, after acquiring the straight line image displayed through the lens film material to be tested, the method further includes using an edge detection algorithm to identify the edge of each straight line in the straight line image.

[0016] In an exemplary embodiment, the angle range of a set of straight lines displayed by the display device is the designed edge angle ± a preset accuracy angle, where the designed edge angle is the expected edge tilt angle and the preset accuracy angle is the allowable error angle.

[0017] On the other hand, this disclosure also provides an angle testing system for performing the aforementioned angle testing method, the system comprising: A display device for displaying a set of straight lines, wherein each straight line in the set of straight lines corresponds to an angle; A fixing platform is used to fix the display device and the lens film to be tested; An image acquisition device is used to acquire a straight line image displayed through the lens film material under test; An image detection device is used to perform image detection on a straight line image acquired by the image acquisition device, and to find a straight line with the same edge angle as the lens film material to be tested, wherein the angle of the straight line is the edge angle of the lens film material to be tested.

[0018] In an exemplary embodiment, the system further includes a first light-transmitting layer disposed between the display device and the lens film to be tested, the thickness of the first light-transmitting layer being such that the focal point of the lens film to be tested is located on the display device.

[0019] In an exemplary embodiment, the system further includes a second light-transmitting layer disposed on the side of the lens film to be tested away from the display device, for fixing the lens film to be tested.

[0020] The edge angle testing method and system of this embodiment can obtain more accurate edge angles, thereby ensuring the cutting accuracy of subsequent film materials. By using the cutting method described in this embodiment, a smaller angle threshold is applied to the first lens film, resulting in higher accuracy for the first lens, thus ensuring the cutting accuracy of the entire batch of lens films.

[0021] Other features and advantages of this application will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the application. Other advantages of this application can be realized and obtained by means of the embodiments described in the description and the accompanying drawings. Attached Figure Description

[0022] The accompanying drawings are used to provide an understanding of the technical solutions of this application and constitute a part of the specification. They are used together with the embodiments of this application to explain the technical solutions of this application and do not constitute a limitation on the technical solutions of this application.

[0023] Figure 1 This is a schematic diagram of the current cutting equipment; Figure 2 This is a flowchart of the membrane material cutting method according to an embodiment of the present disclosure; Figure 3 This is a flowchart of the lens film edge angle detection method according to an embodiment of the present disclosure; Figure 4 This is a flowchart of the cutting and detection scheme according to an embodiment of the present disclosure; Figure 5 A schematic diagram of the alignment reference line on the cutting machine table; Figure 6 A schematic diagram of setting limit blocks on the cutting machine platform; Figure 7 This is a schematic diagram of the cutting outline on the cutting machine table; Figure 8A This is a front view of the test bench; Figure 8B Side view of the test bench; Figure 9 This is a partial schematic diagram of the test lines; Figure 10 This is a schematic diagram showing the positional relationship between the image acquisition device and the lens. Figure 11 A schematic diagram of an image acquired by an image acquisition device; Figure 12A This is a schematic diagram of the line edge; Figure 12B This is a schematic diagram showing the position of the center line of the line; Figure 13 This is a schematic diagram of a 2.5-dimensional angle measurement method. Detailed Implementation

[0024] This application describes several embodiments, but these descriptions are exemplary and not limiting, and it will be apparent to those skilled in the art that many more embodiments and implementations are possible within the scope of the embodiments described herein. Although many possible combinations of features are shown in the drawings and discussed in the detailed description, many other combinations of the disclosed features are also possible. Unless specifically limited, any feature or element of any embodiment may be used in combination with, or may replace, any feature or element of any other embodiment.

[0025] This application includes and contemplates combinations of features and elements known to those skilled in the art. The embodiments, features, and elements disclosed in this application can also be combined with any conventional features or elements to form unique inventive solutions. Any feature or element of any embodiment can also be combined with features or elements from other inventive solutions to form another unique inventive solution. Therefore, it should be understood that any feature shown and / or discussed in this application can be implemented individually or in any suitable combination. Therefore, the embodiments are not limited except by the limitations imposed by the appended claims and their equivalents. Furthermore, various modifications and changes can be made within the scope of the appended claims.

[0026] Furthermore, in describing representative embodiments, the specification may have presented methods and / or processes as a specific sequence of steps. However, the method or process should not be limited to the specific order of steps described herein, to the extent that it does not depend on such a specific order. As will be understood by those skilled in the art, other sequences of steps are also possible. Therefore, the specific order of steps set forth in the specification should not be construed as a limitation of the claims. Moreover, the claims concerning the method and / or process should not be limited to the steps performed in the written order, and those skilled in the art will readily understand that these orders can be varied and still remain within the spirit and scope of the embodiments of this application.

[0027] To achieve stereoscopic and dual-view display, lens grating technology is typically used, which involves bonding cylindrical lens film to the display side of the display panel. This film is composed of a large number of micro-cylindrical lenses arranged side by side with extremely high precision. The edges of the lenses are parallel, and the spacing between the lenses is usually between tens and hundreds of micrometers. Therefore, the cutting precision of the lens film is required to be high.

[0028] Current cutting equipment such as Figure 1As shown, the device includes a cutting table, a slide rail mounted above the cutting table, and a cutter head positioned on the slide rail. The slide rail can move along the X-axis above the cutting table, and the cutter head can move along the slide rail along the Y-axis, allowing the cutter head to be moved to any position on the cutting table to cut the film material. The movement of the slide rail and cutter head in the cutting equipment is controlled by a control terminal connected to the cutting equipment. Currently, the cutting accuracy of the cutting equipment is determined by the movement accuracy of the slide rail and cutter head, as well as the control accuracy of the control terminal, resulting in a cutting accuracy of approximately 0.2 degrees, which cannot meet the cutting accuracy requirements of cylindrical lenses.

[0029] Therefore, this disclosure provides a method for cutting film materials, which can cut lens film materials (especially suitable for cylindrical lens film materials) and meet their cutting accuracy requirements. Figure 2 As shown, it includes the following steps: Step 11: Set the cutting position and cut the lens film; Step 12: If the current lens film is the first lens film in this batch, perform the first film angle test to obtain the actual edge angle of the first lens film. If the difference between the actual edge angle of the first lens film and the designed edge angle is less than or equal to the first angle threshold, continue cutting the lens film. If the difference between the actual edge angle of the first lens film and the designed edge angle is not less than the first angle threshold, reset the cutting position and repeat the cutting of the lens film and the first film angle test. Step 13: If the current lens film is not the first lens film, perform an angle test on the non-first lens film to obtain the actual edge angle of the non-first lens film. If the difference between the actual edge angle of the non-first lens film and the designed edge angle is less than or equal to the second angle threshold, continue cutting the lens film. If the difference between the actual edge angle of the non-first lens film and the designed edge angle is not less than the second angle threshold, reset the cutting position and repeat the lens film cutting and non-first lens film angle test. The first angle threshold is less than the second angle threshold.

[0030] Since the precision of the film material cut in the same batch will not differ too much, by using a smaller angle threshold for the first lens film material, the cutting precision of the first lens film material can be controlled to reach a higher level, thereby ensuring the cutting precision of the entire batch of lens film materials.

[0031] The aforementioned non-first lens angle testing method can be the same as the first lens angle testing method, or a different method can be used. Since the first lens requires higher precision control, a higher precision testing method can be used. Conversely, for non-first lenses, the precision control requirements are relatively lower, so a lower precision angle testing method can be used.

[0032] For example, for non-first lenses, angle testing can be done by sampling. However, for the first lens, angle testing is mandatory. If the first lens in a batch fails the angle test, the second lens cut after adjusting the cutting position will still be considered the first lens and undergo angle testing until it passes. Therefore, in this example, "first lens" refers to all lenses that need to be tested according to the first lens angle testing method.

[0033] This embodiment also provides an angle testing method, which can be applied to the edge angle testing of the aforementioned first lens, and also to the edge angle testing of non-first lenses, such as... Figure 3 As shown, the method includes: Step 21: Send display data to the display device so that the display device displays a set of straight lines, and each straight line in the set of straight lines corresponds to an angle; For example, the angle range of the set of straight lines is the designed edge angle ± the preset accuracy angle, that is, the minimum angle is the designed edge angle - the preset accuracy angle, and the maximum angle is the designed edge angle + the preset accuracy angle. The designed edge angle is the expected edge inclination angle, that is, the angle between the edge and the cutting edge. The cutting edge can be the first side (e.g., the short side) or the second side adjacent to the first side (e.g., the long side). The preset accuracy angle is the allowable error angle, that is, the accuracy requirement (or design accuracy) for the first piece, and the error angle range is, for example, 0.01°-0.2°. For example, it can be 0.01° or 0.05°. Controlling the edge angle of the Lens film material can ensure the display effect of stereoscopic display or dual-view display.

[0034] After determining the angular range of the set of lines, the number of lines in the set can be calculated based on the unit precision: Number of lines = 2 * preset precision angle / unit precision. Unit precision, or precision step size, is the difference in angle between two adjacent lines. It can be the minimum measurable precision or a precision step size set as needed (e.g., determined by the number of lines), with a range of 0.001°-0.01°. For example, if the design precision is 0.01 and the unit precision is 0.001, then the number of lines in the set is 2 * 0.01 / 0.001 = 20. Similarly, if the design precision is 0.05 and the unit precision is 0.005, then the number of lines in the set is 2 * 0.05 / 0.005 = 20. And if the design precision is 0.1 and the unit precision is 0.005, then the number of lines in the set is 2 * 0.1 / 0.005 = 40.

[0035] In other embodiments, a fixed number of lines can be set, i.e., the number of lines to be displayed is determined first. For example, k lines are set, with the line having the same angle as the designed edge angle placed at the center of this group of lines, i.e., displayed in the center. On one side of this line, lines with different angles are arranged in decreasing increments with unit precision, and on the other side of this line, lines with different angles are arranged in increasing increments with unit precision. For example, a total of 41 lines are set, where the angle of the center line is the designed edge angle, for example, 10°, with a unit precision of 0.01. Then, the angles of the lines on the left are 9.99, 9.98, 9.97, ..., and the angles of the lines on the right are 10.01, 10.02, 10.03, ..., respectively. In this example, the group of lines are arranged in order of angle value, such as from largest to smallest or smallest to largest. In other embodiments, it is not excluded that they may not be arranged in order of angle value.

[0036] Step 22: Acquire a straight line image displayed through the lens film material under test, perform image detection on the straight line image, and find a straight line with the same edge angle as the lens film material under test. The angle of the straight line is the edge angle of the lens film material under test.

[0037] A straight line image is acquired through the lens film material under test. By detecting the image, if a complete straight line can be seen, it means that the angle of the lens edge is the same as the angle of the straight line. In other words, the longer the displayed straight line is, the closer it is to the actual edge angle. Therefore, the angle of the longest displayed straight line is taken as the edge angle of the lens film material under test.

[0038] Considering potential errors, the straight lines with the same angle as the edge of the lens film being tested include straight lines with exactly the same angle, or straight lines with approximately the same angle.

[0039] The edge angle testing method of this embodiment can quickly and accurately obtain the actual edge angle of the current lens film, and the difference between the actual edge angle and the designed edge angle is the cutting accuracy of the current lens film. It also allows for rapid acquisition of cutting accuracy. Using this method, a more accurate edge angle can be obtained, thereby ensuring the subsequent cutting accuracy of the film.

[0040] In an exemplary embodiment, the image detection of the straight line image described above includes: calculating the contrast of each straight line in the straight line image; comparing the contrast of all straight lines; identifying the straight line with the lowest contrast as the straight line with the same edge angle as the lens film material under test; and if there are two or more straight lines with the lowest contrast, then the average of the angles corresponding to these lines is taken as the edge angle of the lens film material under test. The longest displayed straight line can be found by calculating the contrast.

[0041] In an exemplary embodiment, when calculating the contrast of each line in the line image, the ratio of the maximum grayscale value to the minimum grayscale value at the center line of each line is calculated as the contrast of the line. Using the contrast at the center line as the contrast of the line is more accurate and reduces errors caused by calculating the edges of the lines. For example, the width of the displayed line can be approximately equal to or less than the width of the cylindrical lens, as long as the width of the line is sufficient to ensure the detection of at least one line with the same angle as the lens edge.

[0042] In an exemplary embodiment, after acquiring a straight line image displayed through the lens film material under test, before detecting the straight line image, an edge detection algorithm can be used to identify the edges of the straight lines in the straight line image. Then, the straight line image is detected. Edge recognition processing can eliminate edge breaks caused by unclear image capture. For example, the Sobel edge detection algorithm can be used, and other edge detection algorithms can also be employed.

[0043] This disclosure also provides an angle testing system for testing the angle of a first-piece Lens, the system comprising: A display device for displaying a set of straight lines, wherein each straight line in the set of straight lines corresponds to an angle; A fixing platform is used to fix the display device and the lens film to be tested; An image acquisition device is used to acquire a straight line image displayed through the lens film material under test; An image detection device is used to perform image detection on a straight line image acquired by the image acquisition device, and to find a straight line with the same edge angle as the lens film material to be tested, wherein the angle of the straight line is the edge angle of the lens film material to be tested.

[0044] The system described in this embodiment can obtain relatively accurate edge angles.

[0045] In an exemplary embodiment, the system further includes a first light-transmitting layer disposed between the display device and the lens film to be tested. The thickness of the first light-transmitting layer ensures that the focal point of the lens film to be tested is located on the display device, thereby guaranteeing the clarity of the linear image.

[0046] In an exemplary embodiment, the system further includes a second light-transmitting layer disposed on the side of the lens film to be tested away from the display device, for fixing the lens film to be tested.

[0047] In an exemplary embodiment, the fixing platform has a certain tilt angle to prevent the display device and the lens film to be tested from falling off.

[0048] The following application example illustrates the overall cutting solution.

[0049] The overall process is as follows Figure 3 As shown, it includes steps 1-4.

[0050] Step 1: Membrane material positioning; Before the initial positioning, a positioning fixture is set up.

[0051] The current cutting machine is a platform. When the film material is placed on the cutting machine, it needs to be aligned first. The current alignment method is to replace the cutter head with a pen and draw an alignment baseline on the cutting machine, for example... Figure 5 The alignment reference line shown is along the X direction. When placing the membrane material, the edge of the membrane is aligned with the reference line. However, this alignment method has poor accuracy. If a visual recognition system is used for positioning, the alignment cost is high and the time consumption is long. To reduce costs and improve efficiency, this embodiment sets a limiting block (positioning fixture) along the alignment reference line at the edge of the cutting machine. The limiting block is used to control the lens alignment, such as... Figure 6 As shown, after setting the limit blocks, the cutting machine table is divided into a limit block area and a film material placement area. When placing the film material to be cut, the lower edge of the film material placed on the cutting machine table is aligned with the edge of the limit block. This allows for rapid positioning while ensuring accuracy, and is cost-effective and efficient.

[0052] Step 2: Set the cutting position; Typically, the lens ridge angle in the raw film material is 0 degrees or 90 degrees. When a specific angle needs to be cut, i.e., the aforementioned designed ridge angle, the cutting position needs to be set. This can be done by inputting a cutting diagram defining the trajectory of the cutting head into the control terminal of the cutting equipment, and modifying one or more of the following cutting parameters: cutting angle, cutting start coordinates, first side length, second side length, etc. The cutting outline is as follows. Figure 7 As shown, α is the cut angle. The cut edge of the lens has a fixed relationship with the ridge angle of the cylindrical lens, such as... Figure 7 As shown, taking the first edge of the Lens as the reference edge as an example, the cutting angle α is the angle between the first edge of the Lens and the edge of the limiting block, and since Figure 7 In the example, the edge angle of the membrane material is 0°, that is, parallel to the edge of the limiting block. Therefore, in Figure 7 In the example, the cutting angle α equals the design edge angle β. In other examples, α may not be equal to β when the reference edge is different, but the relationship between the two can be calculated, so the design edge angle of the Lens can be guaranteed by adjusting the cutting angle.

[0053] To ensure cutting quality and protect the blade, rubber pads are laid on some cutting machine tables. However, there may be air pockets between the rubber pads and the cutting machine table (e.g., Figure 7As shown in the figure, these voids can cause the lens to lose accuracy during cutting. Therefore, after inputting the cutting diagram to define the trajectory of the cutter head at the control terminal of the cutting equipment, it is possible to check whether there are voids in the cutting contour. If there are voids, the cutting position is adjusted to avoid the voids, so as to ensure that there are no voids in the cutting contour.

[0054] If subsequent angle tests do not meet the requirements, return to this step to readjust the cutting position.

[0055] Step 3, Lens trimming; For example, before cutting the lens, the negative pressure of the cutting equipment can be activated to allow the lens to be attracted to the cutting table. The blade can be switched to a lightweight brush to smooth the lens and remove air bubbles. After checking that there are no air bubbles within the cutting outline of the cutting table, the brush can be switched back to the blade, and the cutting equipment can be started to cut the lens to complete the cutting.

[0056] Step 4, Angle Test Since the cutting precision of membrane materials within the same batch varies only slightly, ensuring the cutting precision of the first membrane material is crucial. Therefore, the angle test in this embodiment includes at least the angle test of the first lens, determining whether the difference between the actual edge angle and the designed edge angle of the first lens is less than or equal to a first angle threshold. Optionally, it may also include angle testing of non-first lenses. In this case, the test can be a sampling inspection, determining whether the difference between the actual edge angle and the designed edge angle of non-first lenses is less than or equal to a second angle threshold. Since the cutting precision of the first lens determines the cutting precision of subsequent lenses in the same batch, the first angle threshold is less than the second angle threshold. For example, the first angle threshold is 0.01° and the second angle threshold is 0.05°; or the first angle threshold is 0.05° and the second angle threshold is 0.1°.

[0057] Figure 4The implementation process includes two angle tests. Specifically, when the angle test begins, it is first determined whether the current lens is the first lens. This can be done, for example, based on the lens identifier or a count value from the control terminal. If it is determined to be the first lens, the angle test for the first lens is performed; if it is determined to be a non-first lens, the angle test for the non-first lens is performed. The testing methods for the angle tests of the first and non-first lenses can be the same or different. When the testing methods are the same, the criteria for passing the test can be set differently; for example, the aforementioned first angle threshold may differ from the second angle threshold. If the test passes, meaning the difference between the actual edge angle and the designed edge angle is less than or equal to the angle threshold, the subsequent lens cutting continues. If the test fails, the process returns to step 2, the cutting position is reset, and then the cutting in step 3 and the angle detection in step 4 are performed until the test passes. When the angle detection is performed again, if it is the first lens, the first lens angle detection is still performed; if it is a non-first lens, the non-first lens angle detection can still be performed, or the first lens angle detection can also be performed.

[0058] The angle testing method is explained below.

[0059] Method 1, set up the test bench. The front view of the test bench is as follows: Figure 8A As shown, the side view is as follows Figure 8B As shown, the test stage includes a tilted fixed platform and a display device located on the fixed platform. The lens is placed on the display side of the display device on the fixed platform. The display device can be implemented using a combination of an LCD open cell and a backlight module (BLU), or an OLED panel. The fixed platform is tilted to prevent the lens from falling. Compared to using clamps, the tilted fixed platform utilizes the lens's own gravity to prevent it from falling, avoiding damage or bending caused by clamps. Optionally, since the lens is a cylindrical lens, a first light-transmitting layer can be provided between the lens and the light-emitting device to ensure that the lens's focus is on the display device, preventing image blurring and facilitating subsequent image processing. The thickness of the first light-transmitting layer depends on the lens's focal length. Optionally, a second light-transmitting layer can also be provided on the side of the lens away from the display device to ensure that the lens fits tightly against the first light-transmitting layer and prevent lens wrinkles. The thickness of the second light-transmitting layer can be less than the thickness of the first light-transmitting layer, as long as it fits the lens. The light-transmitting layer can be made of glass.

[0060] Turn on the display device, which displays a test pattern (i.e., a pattern containing a set of straight lines at different angles). The test pattern consists of n straight lines, with the angle range from the starting angle to the ending angle. The starting angle = designed edge angle - preset precision angle, and the ending angle = designed edge angle + preset precision angle, increasing in fixed precision steps; or the starting angle = designed edge angle + preset precision angle, and the ending angle = designed edge angle - preset precision angle, decreasing in fixed precision steps. The designed edge angle is the angle of the edge relative to the edge of the film material after cutting, i.e., the desired edge angle. The preset precision angle can be related to an angle threshold. For example, for the first lens, the preset precision angle is 0.01, with an angle range of designed edge angle ± 0.01; while for non-first lenses, the preset precision angle is 0.05, with an angle range of designed edge angle ± 0.05. n = angle range / preset precision step. For example, if the angle of the edge is designed to be 10 degrees, and the preset precision angle is 0.02, then the angle range of the line is 9.98-10.02. Assuming the step size is 0.001, the test pattern contains 40 test lines, each corresponding to an angle. A partial example of the test lines is shown below. Figure 9 As shown in the figure, the lines in the figure are at different angles from left to right.

[0061] An image acquisition device is used to acquire a straight line image displayed through a lens. The image acquisition device is placed in front of the aforementioned test platform, i.e., facing the lens. Preferably, the distance between the image acquisition device and the lens meets the lens's optimal viewing distance to ensure the acquired test pattern is clear; the optimal viewing distance varies for different lenses. Preferably, the image acquisition device is perpendicular to the center point of the lens under test. The image acquisition device can be, for example, a camera, and its positional relationship with the lens is as follows: Figure 10 As shown.

[0062] The image of a straight line acquired by the image acquisition device (hereinafter referred to as the acquired image) is, for example... Figure 11 As shown. Since the lens is a cylindrical lens, if a straight line in the test pattern can be completely displayed within the cylindrical period, then the angle of that straight line is the actual edge angle of the current lens, and it can also determine the cutting accuracy of the current lens (the difference between the actual edge angle and the designed edge angle). Based on this principle, it is necessary to find the longest one or two straight lines from the acquired image.

[0063] First, edge processing is performed on the test line in the acquired image to prevent misjudgment due to unclear line edges. For example, the Sobel edge detection algorithm can be used to process the acquired image to obtain the edges of the test line. Since the pixel values ​​change drastically at the edge of the line in the image, the corresponding gradient values ​​will be large. Therefore, by using convolution operations, the approximate gradient values ​​of the image in the horizontal (x) and vertical (y) directions are calculated separately. By combining the gradients in the two directions, the location of drastic gray-level changes in the image, i.e., the edge, can be found.

[0064] The specific method is as follows: A horizontal operator is used to detect edges in the vertical direction. For example, the horizontal operator can use the following convolution kernel: The horizontal gradient matrix is ​​obtained by convolving the image with the horizontal direction operator. The calculation formula is: Gx = acquired image * horizontal direction operator.

[0065] Horizontal edges can be detected using a vertical direction operator. For example, a vertical direction operator can use a convolution kernel as shown below: The vertical gradient matrix is ​​obtained by convolving the image with the vertical direction operator. The calculation formula is: Gy = acquired image * vertical direction operator.

[0066] For each pixel in the image, calculate the gradient value G of that point using Gx and Gy: G = SQRT(Gx*Gx+Gy*Gy), where SQRT is the square root. A larger G value indicates more drastic pixel changes and a higher probability of it being an edge. Compare the gradient value of each point with a preset threshold, which can range from 0.3 to 0.8. Points with a gradient greater than the threshold are considered edge points and have a value of 1; non-edge points have a value of 0. This yields the edge map of the test line, as shown below. Figure 12A As shown.

[0067] Based on the edge values ​​of each test line, the position coordinates of the line's centerline are calculated. The position of the line's centerline is as follows: Figure 12BAs shown, read the grayscale value at the center line position (e.g., using MATLAB), calculate the contrast at the center line position (= maximum grayscale value / minimum grayscale value), and select the line with the same angle as the test line based on the contrast at the center line position. When the difference between the maximum and minimum grayscale values ​​is large, it indicates that the line is interrupted. Therefore, by comparing the contrast, the longest uninterrupted line can be obtained. Compare the contrast at the center line position of each line; the line angle corresponding to the line with the smallest contrast value is the actual edge angle of the lens. In a special case, if there are two lines with the smallest contrast values ​​(line m and line m+1), that is, two lines have the same minimum contrast value, calculate the average angle of these two lines as the actual edge angle of the lens. Lens actual edge angle = (angle value of line m + angle value of line (m+1)) / 2.

[0068] Using contrast as the criterion, compared to using brightness, eliminates the interference of uneven backlight brightness, resulting in a more accurate result.

[0069] Method 2: Calculate the cutting angle using the angle of the scrap material after Lens cutting. For example, lay the cut scrap material flat on a 2.5D image measuring instrument (hereinafter referred to as 2.5D), and use a light-transmitting layer to flatten the membrane material; start the 2.5D instrument, focus on the cutting edge and the edge of the Lens membrane material respectively, prioritize selecting the long side of the scrap material for measurement, and the length of each selected point is preferably >50cm to ensure the accuracy of the angle, and read the angle, which is the cutting angle of the Lens. Figure 13 This is a schematic diagram of angle measurement using a 2.5-dimensional method.

[0070] As can be seen, Method 1 has higher accuracy and can be used for angle testing of both the first and second lenses. Method 2 can be used for angle testing of the second lens. After testing the angle of the first lens, the relationship between the actual edge angle and the cutting angle can be obtained. When using Method 2 for angle testing of the second lens, after measuring the cutting angle, the actual edge angle can be calculated, and then the actual edge angle can be used to determine whether the current lens meets the design requirements.

[0071] By employing the method described in this embodiment, and through optimizing the lens grating cutting process and angle testing method, high-precision film material cutting is achieved, which can greatly improve detection efficiency and accuracy.

[0072] The terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first," "second," etc., may explicitly or implicitly include at least one of those features.

[0073] In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise expressly and specifically limited.

[0074] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," "fixing," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral part; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0075] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0076] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. An angle testing method, characterized in that, The method for testing the ridge angle of a cut lens film includes: Send display data to the display device so that the display device displays a set of straight lines, and each straight line in the set of straight lines corresponds to an angle; A straight line image displayed through the lens film under test is acquired. Image detection is performed on the straight line image to find a straight line with the same edge angle as the lens film under test. The angle of the straight line is the edge angle of the lens film under test, wherein: Calculate the contrast of each line in the line image, compare the contrast of all lines, and take the line with the smallest contrast as the line with the same edge angle as the lens film material under test. The angle of the line is the edge angle of the lens film material under test. Alternatively, calculate the contrast of each line in the line image, compare the contrast of all lines, find the two lines with the smallest contrast, and take the average of the angles of the two lines as the edge angle of the lens film material under test.

2. The method according to claim 1, characterized in that, The angle range of the set of straight lines is the designed edge angle ± the preset accuracy angle, where the designed edge angle is the expected edge tilt angle and the preset accuracy angle is the allowable error angle.

3. The method according to claim 1, characterized in that, The calculation of the contrast of each line in the line image includes: The ratio of the maximum grayscale value to the minimum grayscale value at the center line of each straight line is calculated as the contrast of the straight line.

4. The method according to claim 1, characterized in that, Before calculating the contrast of each line in the line image, the method further includes: using an edge detection algorithm to identify the edges of each line in the line image.

5. The method according to claim 1, characterized in that, The set of straight lines are arranged in order of angle values, and the number of straight lines is the quotient of twice the preset precision angle and the unit precision.

6. A method for cutting membrane material, characterized in that, The method for cutting lens film materials includes: Set the cutting position and cut the lens film material; If the current lens film is the first lens film in this batch, perform the first film angle test to obtain the actual edge angle of the first lens film. Determine whether the difference between the actual edge angle and the designed edge angle is less than or equal to the first angle threshold. If yes, continue cutting the lens film. If no, reset the cutting position and repeat the cutting of the lens film and the first film angle test. If the current lens film material is not the first lens film material, perform a non-first film material angle test to obtain the actual edge angle of the non-first lens film material. Determine whether the difference between the actual edge angle and the designed edge angle is less than or equal to a second angle threshold. If yes, continue cutting the lens film material. If no, reset the cutting position and perform lens film cutting and non-first film material angle tests. The first angle threshold is less than the second angle threshold. The method for testing the angle of the first film material includes: sending display data to a display device to display a set of straight lines, each of which corresponds to an angle; acquiring an image of the straight lines displayed through the film material to be tested; performing image detection on the straight line image to find a straight line with the same edge angle as the film material to be tested, wherein the angle of the straight line is the edge angle of the film material to be tested; and calculating the contrast of each straight line in the straight line image, comparing the contrast of all straight lines, and taking the straight line with the lowest contrast as the straight line with the same edge angle as the film material to be tested, wherein the angle of the straight line is the edge angle of the film material to be tested; or calculating the contrast of each straight line in the straight line image, comparing the contrast of all straight lines, finding the two straight lines with the lowest contrast, and taking the average of the angles of the two straight lines as the edge angle of the film material to be tested.

7. The method according to claim 6, characterized in that, The method for testing the angle of the non-first membrane material may be the same as or different from the method for testing the angle of the first membrane material.

8. The method according to claim 6, characterized in that, The calculation of the contrast of each line in the line image includes: The ratio of the maximum grayscale value to the minimum grayscale value at the center line of each straight line is calculated as the contrast of the straight line.

9. The method according to claim 6, characterized in that, After acquiring the straight line image displayed through the lens film material under test, the method further includes using an edge detection algorithm to identify the edge of each straight line in the straight line image.

10. The method according to claim 6, characterized in that, The angle range of a set of straight lines displayed by the display device is the designed edge angle ± preset accuracy angle, where the designed edge angle is the expected edge tilt angle and the preset accuracy angle is the allowable error angle.

11. An angle testing system for performing the angle testing method according to any one of claims 1-5, the system comprising: A display device for displaying a set of straight lines, wherein each straight line in the set of straight lines corresponds to an angle; A fixing platform is used to fix the display device and the lens film to be tested; An image acquisition device is used to acquire a straight line image displayed through the lens film material under test; An image detection device is used to perform image detection on a straight line image acquired by the image acquisition device, and to find a straight line with the same edge angle as the lens film material under test, wherein the angle of the straight line is the edge angle of the lens film material under test, and wherein: Calculate the contrast of each line in the line image, compare the contrast of all lines, and take the line with the smallest contrast as the line with the same edge angle as the lens film material under test. The angle of the line is the edge angle of the lens film material under test. Alternatively, calculate the contrast of each line in the line image, compare the contrast of all lines, find the two lines with the smallest contrast, and take the average of the angles of the two lines as the edge angle of the lens film material under test.

12. The system according to claim 11, characterized in that, The system further includes a first light-transmitting layer disposed between the display device and the lens film to be tested, the thickness of the first light-transmitting layer being such that the focal point of the lens film to be tested is located at the display device.

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