Displacement detection method, screen detection method and detection device

Abstract

The present application relates to the technical field of flexible screen detection, and provides a displacement detection method, a screen detection method, a detection device, a storage medium and a program product. In the method, both the first image (the flexible screen is in an unfolded state) and the second image (the flexible screen is in a non-expanded state) include a first side surface perpendicular to the bending line of the flexible screen, so as to ensure that the displacement of each film layer during the bending process can be observed and measured according to the first image and the second image; at the same time, the key point is a special convex point, concave point or marking point on the film layer that can be distinguished from other points, so as to avoid measurement errors caused by confusion of the key points; and when the camera acquires the first image and the second image, the vertical distance from the first side surface of the flexible screen is the same, and the height of the camera remains unchanged, so as to avoid displacement measurement errors caused by changes in the height of the camera and changes in the vertical distance between the camera and the first side surface of the flexible screen.

Description

Technical Field

[0001] The present application relates to the technical field of flexible screen detection, and in particular to a displacement detection method, a screen detection method, a detection device, a storage medium and a program product. Background Art

[0002] With the development of technology, there are more and more foldable flexible mobile phone products on the market. These mobile phones use flexible screen technology, which allows the flexible screen to bend and unfold within a certain range. The flexible screen is composed of multiple film layers, which are usually bonded with glue. When the flexible screen is bent, due to the different physical properties and bonding methods of the film layer materials, the film layers of the flexible screen may have different degrees of displacement in the direction perpendicular to the bending line during the bending process.

[0003] The displacement of different layers of the flexible screen needs to be consistent with the expected displacement during product design. If the actual displacement is inconsistent with the design, it may cause problems such as screen delamination and poor screen display. Therefore, there is an urgent need for a method that can accurately measure the displacement of each film layer of the flexible screen during the bending process. Summary of the invention

[0004] The present application provides a displacement detection method, a screen detection method, a detection device, a storage medium and a program product, and provides a method for accurately measuring the displacement of each film layer of a flexible screen during a bending process.

[0005] In order to achieve the above objectives, this application adopts the following technical solutions:

[0006] In a first aspect, a displacement detection method is provided, firstly, a camera is used to obtain a first image of a flexible screen in an unfolded state and a second image of a flexible screen in a non-expanded state, wherein the flexible screen includes a first side surface, the first side surface is perpendicular to a bending line of the flexible screen, the first image and the second image both include the first side surface, and the first side surface includes each film layer of the flexible screen; when the camera obtains the first image and the second image, the vertical distance from the first side surface is the same, and the height of the camera remains unchanged; secondly, according to the first image and the second image, a first position and a second position of a key point of each film layer in the flexible screen are determined, wherein the key point is a protruding point and / or a recessed point formed during the preparation of the flexible screen, or the key point is an identification point formed on each film layer of the flexible screen after the preparation of the flexible screen is completed; the first position is the position of the key point of each film layer in the first image, and the second position is the position of the key point of each film layer in the second image; finally, according to the first position and the second position of the key point of each film layer in the flexible screen, the displacement of each film layer during the bending process of the flexible screen is determined.

[0007] In the embodiment of the present application, a displacement detection method is provided, which is applied to the detection of the displacement of each film layer in the flexible screen. Since the displacement direction of each film layer of the flexible screen is perpendicular to the bending line of the flexible screen, the first image (flexible screen is in the unfolded state) and the second image (flexible screen is in the non-expanded state) both include the first side perpendicular to the bending line of the flexible screen, ensuring that the displacement of each film layer during the bending process can be observed and measured according to the first image and the second image; at the same time, the key points of each film layer are the convex points and / or concave points formed during the preparation of the flexible screen, or the identification points formed on each film layer of the flexible screen after the preparation of the flexible screen is completed. The key points are special points on the film layer that can be distinguished from other points, avoiding measurement errors caused by confusion of key points; and the vertical distance between the camera and the first side of the flexible screen when acquiring the first image and the second image is the same, and the height of the camera is unchanged, which can avoid the displacement measurement errors caused by the change of the height of the camera and the change of the vertical distance between the camera and the first side of the flexible screen. In summary, in this embodiment, accurate measurement of the displacement of each film layer during the bending process of the flexible screen can be achieved. Furthermore, since the first side surface in the first image and the second image includes each film layer of the flexible screen, the integrity of the displacement measurement result is also ensured.

[0008] In a possible implementation of the first aspect, the flexible screen includes a first screen and a second screen, the non-expanded state is formed by the first screen remaining stationary and the second screen being bent toward the first screen, and the first side surface is a side surface of the first screen. In this embodiment, this method is used to ensure that each film layer in the captured image is in a horizontal state as much as possible, which is convenient for subsequent calculations.

[0009] In a possible implementation of the first aspect, the displacement of each film layer during the bending process of the flexible screen is determined according to the first position and the second position of the key point of each film layer in the flexible screen, including: determining the first horizontal coordinate of the first position of the key point of each film layer in the flexible screen, and the second horizontal coordinate of the second position; and determining the absolute value of the difference between the first horizontal coordinate and the second horizontal coordinate of the key point of each film layer as the displacement of each film layer during the bending process of the flexible screen.

[0010] In a possible implementation of the first aspect, determining the first position and the second position of the key points of each film layer in the flexible screen according to the first image and the second image includes: determining the third image according to the first image, and determining the fourth image according to the second image, wherein the extension direction of each film layer of the flexible screen in the third image and the fourth image is parallel to the horizontal direction; determining the position of each film layer in the flexible screen in the third image and the fourth image according to the grayscale value of each row of pixels in the third image and the fourth image; determining the first position and the second position of the key points of each film layer in the flexible screen according to the position of each film layer in the flexible screen in the third image and the fourth image.

[0011] In this embodiment, due to the limitations of the camera movement accuracy and the flatness of the desktop on which the flexible screen is placed, each film layer in the first image and the second image captured by the camera may be slightly tilted; or because the camera remains stationary when capturing the first image and the second image, and the first side of the first screen moves, each film layer in the second image captured by the camera is obviously tilted. Therefore, it is necessary to first perform a horizontal calibration on the extension direction of the film layer of the flexible screen in the first image and the second image to facilitate the subsequent displacement calculation of each film layer.

[0012] In a second aspect, a flexible screen detection method is provided, comprising: using a camera to acquire a first image of the flexible screen in an unfolded state and a second image of the flexible screen in a non-expanded state, wherein the flexible screen includes a first side surface, the first side surface is perpendicular to a bending line of the flexible screen, the first image and the second image both include the first side surface, and the first side surface includes each film layer of the flexible screen; when the camera acquires the first image and the second image, the vertical distance from the first side surface is the same, and the height of the camera remains unchanged; according to the first image and the second image, determining a first position and a second position of a key point of each film layer in the flexible screen, wherein the key point is a protrusion point and / or a projection point formed during the preparation process of the flexible screen. Or a depressed point, or, the key point is an identification point formed on each film layer of the flexible screen after the flexible screen is prepared; the first position is the position of the key point of each film layer in the first image, and the second position is the position of the key point of each film layer in the second image; according to the first position and the second position of the key point of each film layer in the flexible screen, the displacement of each film layer during the bending process of the flexible screen is determined; the displacement of each film layer during the bending process of the flexible screen is compared with the preset displacement threshold of each film layer, if the displacement of any film layer exceeds the corresponding preset displacement threshold, the detection is determined to be unqualified; if the displacement of any film layer does not exceed the corresponding preset displacement threshold, the detection is determined to be qualified.

[0013] In this embodiment, after determining the displacement of each film layer during the transformation of the flexible screen from the first image to the second image, the displacement of each film layer is compared with the preset displacement threshold of each film layer. If the displacement of any film layer exceeds its corresponding preset displacement threshold, it can be considered that the flexible screen will be delaminated after long-term use, which will lead to display problems such as black spots. Therefore, it is determined that the flexible screen fails the test. If the displacement of each film layer does not exceed its corresponding preset displacement threshold, it is determined that the flexible screen passes the test.

[0014] It is achievable by testing the displacement of each film layer during the bending of flexible screens made of various different materials, as well as testing the displacement of each film layer during the bending of flexible screens using different types of glue as adhesives, and then guiding designers to select film layer materials and glue types based on the test results.

[0015] In a possible implementation of the second aspect, there are multiple second images, and the bending angles of the flexible screen in any two of the second images are different; determining the displacement of each film layer during the bending process of the flexible screen according to the first position and the second position of the key point of each film layer in the flexible screen, including: for each second image, determining the displacement of each film layer in the process of transforming the flexible screen from the first image to the second image according to the first position and the second position of the key point of each film layer in the flexible screen; determining the maximum displacement of each film layer in multiple second images, and determining the maximum displacement of each film layer as the displacement of each film layer during the bending process of the flexible screen.

[0016] In this embodiment, the maximum displacement of each film layer is compared with a preset displacement threshold of each film layer, thereby further ensuring the accuracy of detection.

[0017] In a third aspect, a detection device is provided, comprising a memory and a processor, the memory being used to store instructions, and when the instructions are executed by the processor, the detection device executes the displacement detection method in the first aspect or any possible implementation of the first aspect, or executes the flexible screen detection method in the second aspect or any possible implementation of the second aspect.

[0018] In a fourth aspect, a computer-readable storage medium is provided, wherein the computer-readable storage medium stores a computer program, wherein the computer program includes program instructions, and when the program instructions are executed, the displacement detection method in the first aspect or any possible implementation of the first aspect is implemented, or the flexible screen detection method in the second aspect or any possible implementation of the second aspect is implemented.

[0019] In a fifth aspect, a computer program product is provided, comprising: a computer program code, which, when executed on a computer, enables the computer to execute the displacement detection method in the first aspect or any possible implementation of the first aspect, or to execute the flexible screen detection method in the second aspect or any possible implementation of the second aspect.

[0020] Based on the implementations provided in the above aspects, this application can also be further combined to provide more implementations. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is an exemplary flow chart of the displacement detection method according to the first aspect provided by an embodiment of the present application;

[0022] Figure 2 is a schematic diagram of a flexible screen provided in an embodiment of the present application in an unfolded state;

[0023] Figure 3 is a schematic diagram of a first image provided in an embodiment of the present application;

[0024] Figure 4 is a side schematic diagram of the flexible screen provided by an embodiment of the present application in a bent state;

[0025] Figure 5 is a schematic diagram of a second image provided in an embodiment of the present application;

[0026] Figure 6 is an exemplary flow chart of the flexible screen detection method according to the second aspect provided by an embodiment of the present application;

[0027] Figure 7 It is a schematic diagram of the structure of the third aspect detection device provided in the embodiment of the present application. DETAILED DESCRIPTION

[0028] The technical solution in this application will be described below in conjunction with the accompanying drawings.

[0029] In the description of the embodiments of the present application, unless otherwise specified, “ / ” means or. For example, A / B can mean A or B. The “and / or” in this article is merely a way to describe the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone.

[0030] In the following, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this embodiment, unless otherwise specified, "plurality" means two or more.

[0031] With the development of technology, there are more and more foldable flexible mobile phone products on the market. These mobile phones use flexible screen technology, which allows the flexible screen to bend and unfold within a certain range. The flexible screen is composed of multiple film layers, which are usually bonded with glue. When the flexible screen is bent, due to the different physical properties and bonding methods of the film layer materials, the film layers of the flexible screen may have different degrees of displacement in the direction perpendicular to the bending line during the bending process.

[0032] The displacement of different layers of the flexible screen needs to be consistent with the expected displacement during product design. If the actual displacement is inconsistent with the design, it may cause problems such as screen delamination and poor screen display. Therefore, there is an urgent need for a method that can accurately measure the displacement of each film layer of the flexible screen during the bending process.

[0033] In view of this, an embodiment of the present application provides a displacement detection method, first, using a camera to obtain a first image of a flexible screen in an unfolded state and a second image in a non-expanded state, wherein the flexible screen includes a first side surface, the first side surface is perpendicular to the bending line of the flexible screen, the first image and the second image both include the first side surface, and the first side surface includes each film layer of the flexible screen; when the camera obtains the first image and the second image, the vertical distance from the first side surface is the same, and the height of the camera remains unchanged; secondly, according to the first image and the second image, the first position and the second position of the key points of each film layer in the flexible screen are determined, wherein the key points are protruding points and / or recessed points formed during the preparation of the flexible screen, or the key points are identification points formed on each film layer of the flexible screen after the preparation of the flexible screen is completed; the first position is the position of the key points of each film layer in the first image, and the second position is the position of the key points of each film layer in the second image; finally, according to the first position and the second position of the key points of each film layer in the flexible screen, the displacement of each film layer during the bending process of the flexible screen is determined.

[0034] In the embodiment of the present application, a displacement detection method is provided, which is applied to the detection of the displacement of each film layer in the flexible screen. Since the displacement direction of each film layer of the flexible screen is perpendicular to the bending line of the flexible screen, the first image (flexible screen is in the unfolded state) and the second image (flexible screen is in the non-expanded state) both include the first side perpendicular to the bending line of the flexible screen, ensuring that the displacement of each film layer during the bending process can be observed and measured according to the first image and the second image; at the same time, the key points of each film layer are the convex points and / or concave points formed during the preparation of the flexible screen, or the identification points formed on each film layer of the flexible screen after the preparation of the flexible screen is completed. The key points are special points on the film layer that can be distinguished from other points, avoiding measurement errors caused by confusion of key points; and the vertical distance between the camera and the first side of the flexible screen when acquiring the first image and the second image is the same, and the height of the camera is unchanged, which can avoid the displacement measurement errors caused by the change of the height of the camera and the change of the vertical distance between the camera and the first side of the flexible screen. In summary, in this embodiment, accurate measurement of the displacement of each film layer during the bending process of the flexible screen can be achieved. Furthermore, since the first side surface in the first image and the second image includes each film layer of the flexible screen, the integrity of the displacement measurement result is also ensured.

[0035] A displacement detection method provided by an embodiment of the present application is described in detail below with reference to the accompanying drawings. Figure 1 is an exemplary flow chart of a displacement detection method.

[0036] Step S101: using a camera to obtain a first image of the flexible screen in an unfolded state and a second image of the flexible screen in a non-expanded state.

[0037] Flexible screen technology is an advancement in display technology. It allows the display screen to be bent or even folded, which is very suitable for use in smartphones, wearable devices and other portable electronic products. The flexible screen has at least the following film layers: substrate layer, display layer, touch layer and protective layer, and the film layers are bonded together by glue. In practical applications, the flexible screen may also include other film layers, which are not listed one by one in this embodiment.

[0038] During the test, a bending carrier can be used to drive the flexible screen to bend. The bending carrier includes a first support plate and a second support plate rotatably connected to the first support plate. Assume that Figure 2As shown, the flexible screen 200 includes a first screen 201 and a second screen 202, the first screen 201 is fixed on a first support plate, and the second screen 202 is fixed on a second support plate, so that during the bending process, the first support plate can remain stationary, the second support plate bends toward the first support plate and drives the second screen 202 to bend toward the first screen 201; or, the second support plate remains stationary, the first support plate bends toward the second support plate and drives the first screen 201 to bend toward the second screen 202; or, the first support plate and the second support plate move simultaneously and move closer to each other, at which time, the first screen 201 and the second screen 202 are also driven to move closer to each other.

[0039] It is worth noting that, since the displacement direction of each film layer of the flexible screen 200 is perpendicular to the bending line of the flexible screen 200 (shown by the dotted line in Figure 2), the displacement of each film layer can only be observed on the side of the screen perpendicular to the bending line of the flexible screen 200, and the displacement of each film layer cannot be observed on the side of the screen parallel to the bending line of the flexible screen 200. Therefore, in this embodiment, the camera captures an image of the first side perpendicular to the bending line of the flexible screen 200 to ensure that the first image and the second image captured by the camera can observe and measure the displacement of each film layer during the bending process. Among them, the first side can be the side of the first screen 201 and the second screen 202, or the side of the first screen 201 or the second screen 202.

[0040] See also Figure 2 and Figure 4 When the camera 100 acquires the first image and the second image of the flexible screen 200, the vertical distance L between the camera 100 and the first side surface of the flexible screen 200 remains unchanged, and the height of the camera 100 remains unchanged, which helps to eliminate the displacement measurement error caused by the viewing angle difference formed by the change in the height of the camera 100 and the change in the vertical distance between the camera 100 and the first side surface of the flexible screen 200, thereby more accurately analyzing the changes in the content of the first image and the second image.

[0041] In one example, during the bending process, the first screen 201 remains stationary, and the second screen 202 is bent toward the first screen 201 to form a non-bent state, and the second image is captured by the camera 100 during the bending process of the second screen 202 toward the first screen 201. When capturing the first image and the second image, the camera 100 is aligned with the side of the first screen 201 and remains stationary, and the camera 100 and the side of the first screen 201 are kept in a relatively horizontal state, ensuring that each film layer in the captured image is in a horizontal state as much as possible, which is convenient for subsequent calculations.

[0042] In another example, during the bending process, the first screen 201 and the second screen 202 move simultaneously. When shooting the first image, the camera 100 is aimed at the side of the first screen 201. When shooting the second image, the camera 100 needs to rotate, and the direction of rotation of the camera 100 is the same as the direction of rotation of the first screen 201, and the angle of rotation of the camera 100 is the same as the angle of rotation of the first screen 201, that is, the camera 100 and the first screen 201 keep synchronous movement. In this way, when shooting the first image and the second image, the camera 100 and the side of the first screen 201 remain in a relatively horizontal state, ensuring that each film layer in the captured image is as horizontal as possible, which is convenient for subsequent calculations.

[0043] In another example, during the bending process, the first screen 201 and the second screen 202 move simultaneously. When shooting the first image, the camera 100 is aimed at the side of the first screen 201 and remains motionless, and the camera 100 and the side of the first screen 201 in the unfolded state remain in a relatively horizontal state. In this way, each film layer in the acquired first image is in a horizontal state, and each film layer in the second image has a certain inclination.

[0044] The following describes how to obtain the first image and the second image by taking the first side surface as the side surface of the first screen 201 as an example:

[0045] The camera 100 is aimed at the first side surface of the first screen 201, the first side surface is perpendicular to the bending line of the flexible screen 200, and the first side surface includes each film layer of the flexible screen 200. Figure 2 As shown, it is a schematic diagram of the flexible screen 200 in the unfolded state. In the unfolded state, the flexible materials of each film layer of the flexible screen 200 are not subjected to force; Figure 3 As shown, the first image captured by the camera 100 when the flexible screen 200 is in the unfolded state includes the first side surface of the first screen 201 of the flexible screen 200. Figure 4 , which is a schematic diagram of the flexible screen 200 in a non-expanded state. The non-expanded state here refers to the first screen 201 remaining stationary, and the second screen 202 being bent toward the first screen 201. In the non-expanded state, each film layer of the flexible screen 200 is subjected to stress. Figure 5 The second image shown is captured by the camera 100 when the flexible screen 200 is in a non-unfolded state. The second image also includes the first side surface of the first screen 201 of the flexible screen 200 .

[0046] Realistically, the second image can be obtained when the second screen 202 of the flexible screen 200 is at a preset angle with the first screen 201, and the preset angle is less than 180°, for example, the preset angle can be 90°, 60° or 0°.

[0047] It is feasible that the second image may be multiple, and the bending angles of the flexible screen 200 in any two second images are different. For example, the multiple second images may be captured in the process of the bending carrier driving the second screen 202 to bend toward the first screen 201. For example, the multiple second images may be 6 second images, and the bending angles of the flexible screen 200 in these 6 second images are 120°, 100°, 90°, 60°, 30°, and 0°, respectively. This is only an example. In actual applications, multiple second images of the flexible screen 200 bent to different angles may be obtained as needed.

[0048] Step S102: Determine the first position and the second position of the key point of each film layer in the flexible screen according to the first image and the second image.

[0049] In a possible implementation, each film layer in the first image and the second image captured by the camera is in a horizontal state. At this time, the first position and the second position of the key point of each film layer in the first image and the second image can be determined in the following way.

[0050] First, the positions of the film layers in the flexible screen in the first image and the second image are determined according to the grayscale values ​​of each row of pixels in the first image and the second image.

[0051] In this embodiment, the grayscale values ​​of each row of pixels along the first direction (usually the horizontal direction) in the first image and the second image are traversed. Specifically, the average grayscale value of each pixel in each row of pixels along the first direction (usually the horizontal direction) in the first image and the second image can be used as the grayscale value of each row of pixels. In this way, a column of pixel grayscale values ​​can be calculated based on the first image.

[0052] By analyzing the change pattern of the grayscale values ​​of different film layers of the flexible screen, the features corresponding to the film layer positions are found. These features may be sudden changes in grayscale values, specific patterns, or other recognizable visual features. For example, the grayscale values ​​of pixels in the same film layer do not change much, while at the edge of the film layer, the grayscale values ​​of pixels change greatly. Therefore, a pixel threshold can be set. If the difference between the grayscale values ​​of two adjacent pixels in the obtained column of pixel grayscale values ​​is not greater than the pixel threshold, it indicates that the pixel row where the pixel grayscale value is located belongs to the same film layer; if the difference between the grayscale values ​​of two adjacent pixels is greater than the pixel threshold, it indicates that the pixel rows where the two pixel grayscale values ​​are located do not belong to the same film layer. In this way, the positions of each film layer in the first image and the second image can be obtained.

[0053] Secondly, according to the positions of the film layers in the flexible screen in the first image and the second image, the first position and the second position of the key point of each film layer in the flexible screen are determined.

[0054] In a possible example, the key points are convex points and / or concave points formed during the preparation of the flexible screen. The convex points are outwardly convex points formed on the surface of the flexible screen, and the concave points are inwardly concave points formed on the surface of the flexible screen. These convex points and / or concave points may be formed during the manufacturing process of the flexible screen due to various reasons (such as heat treatment, mechanical stress, material inhomogeneity, etc.).

[0055] In this embodiment, the first position and the second position of the key point of each film layer in the flexible screen can be determined by the following two methods.

[0056] In one possible implementation, the first characteristic information and the first position of all the raised points and / or sunken points of each film layer in the first image are determined according to the position of each film layer in the flexible screen in the first image; the second characteristic information and the second position of all the raised points and / or sunken points of each film layer in the second image are determined according to the position of each film layer in the flexible screen in the second image; the raised points / sunken points in each film layer having the same first characteristic information and second characteristic information are determined as key points; and the first position and the second position of the key points in each film layer are determined.

[0057] First, feature information is extracted. For each film layer in the first image, first feature information (such as shape, size, texture, etc.) of all convex points and / or concave points of each film layer and their first positions in the first image are extracted according to the positions of each film layer in the first image. For each film layer in the second image, second feature information of all convex points and / or concave points of each film layer and their second positions in the second image are also extracted.

[0058] Then, key points are matched. The feature information of the raised points and / or sunken points of each film layer in the first image and the second image is compared to find out the points with the same feature information, and the raised points and / or sunken points with the same feature information are determined as key points. These key points maintain certain identification features during the process of the flexible screen changing from the unfolded state to the non-expanded state.

[0059] Finally, the key point positions are determined. Based on the characteristic information of the determined key points, the first positions of the key points of each film layer in the first image and the second positions of the key points of each film layer in the second image can be determined. In this way, the position changes of the key points of the flexible screen during the deformation process can be tracked and analyzed, thereby evaluating the physical properties and reliability of the flexible screen.

[0060] Assume that in the first image, there is an obvious raised point on the display layer, whose feature information includes shape (circle) and size (diameter 5 pixels), and the position is (100, 150); in the second image, due to the bending of the screen, the position of this raised point may become (110, 150). By matching the feature information, it can be confirmed that the points in the two images are the same key point in the display layer. In this way, the displacement of the display layer during the bending process can be obtained based on the first position and second position of the same key point on the display layer.

[0061] In another possible implementation method, according to the position of each film layer in the flexible screen in the first image, the first characteristic information and the first position of the protruding point / depressed point of each film layer in the first image are determined; the protruding point / depressed point of each film layer in the first image is determined as the key point of each film layer; according to the first characteristic information of the key point of each film layer and the position of each film layer in the flexible screen in the second image, the second position of the key point of each film layer in the second image is determined.

[0062] First, feature information is extracted. For each film layer in the first image, first feature information (such as shape, size, texture, etc.) of all protruding points and / or recessed points in each film layer and their first positions in the first image are extracted.

[0063] Then, the convex points or concave points identified in the first image are marked as key points. Specifically, at least one representative convex point or concave point may be selected as the key point.

[0064] Finally, the feature information of the key points is used to find corresponding points in the second image through image matching technology. The second position of these points in the second image is recorded. In this way, the position changes of the key points of the flexible screen during the deformation process can be tracked and analyzed, so as to evaluate the physical properties and reliability of the flexible screen.

[0065] Suppose there is a flexible screen, and a raised point is formed on the display layer during its preparation. Through image processing, we determine the position of the display layer in the first image. On the display layer, we find a circular raised point with a diameter of 10 pixels, located at the coordinates (100, 150). We mark this raised point as the key point of the display layer and record its characteristic information (circular, diameter 10 pixels) and position (100, 150). For the second image, first determine the position of the display layer in the second image, and then find a key point matching it in the second image based on the characteristic information of the key point of the display layer and the position of the display layer in the second image. Due to the deformation of the flexible screen, the position of this key point in the second image becomes (110, 150). In this way, the displacement of the display layer during the bending process can be obtained based on the first position and the second position of the same key point on the display layer.

[0066] In another possible example, the key point is a marking point formed on each film layer of the flexible screen after the flexible screen is manufactured. For example, after the flexible screen is manufactured, a vertical line perpendicular to the display surface of the first screen can be formed on the first side of the flexible screen, and the vertical line spans each film layer. In this way, the marking point formed by the vertical line in each film layer can be used as the key point.

[0067] In another possible implementation, due to the limitation of the camera movement accuracy and the flatness of the desktop on which the flexible screen is placed, each film layer in the first image and the second image captured by the camera may be slightly tilted; or because the camera remains stationary when capturing the first image and the second image, and the first side of the first screen moves, each film layer in the second image captured by the camera has an obvious tilt. Therefore, it is necessary to first perform a horizontal calibration on the extension direction of the film layer of the flexible screen in the first image and the second image to facilitate the subsequent displacement calculation of each film layer.

[0068] First, the third image is determined according to the first image, and the fourth image is determined according to the second image, and the extension direction of each film layer of the flexible screen in the third image and the fourth image is parallel to the horizontal direction.

[0069] Using image processing technology (such as Hough transform), the edge lines of each film layer of the flexible screen in the extension direction are extracted from the first image and the second image. The edge lines represent the outline or boundary of the film layer. In the first image, the angle between the edge line of the film layer and the first edge of the image (usually the top or bottom edge of the image) is measured. In the second image, the angle between the edge line of the film layer and the first edge of the image is also measured. According to the first angle measured in the first image, the first image is rotated to obtain the third image. The purpose of the rotation is to make the edge lines of all film layers in the image parallel to the first edge of the image. The extension direction of the edge lines of each film layer in the third image obtained by the rotation transformation is the same as the horizontal direction. Similarly, according to the second angle measured in the second image, the second image is rotated to obtain the fourth image. The extension direction of the edge lines of each film layer in the fourth image obtained by the rotation transformation is the same as the horizontal direction.

[0070] The following specifically describes the rotation transformation of an image by taking the rotation transformation of the first image according to the first angle as an example.

[0071] Exemplarily, a first rotation matrix is ​​determined based on the first angle; the position of each pixel after the rotation transformation is determined based on the position of each pixel in the first image and the first rotation matrix; and a third image is constructed based on the position of each pixel after the rotation transformation.

[0072] Specifically, the rotation matrix R(θ) can be determined according to the first angle θ, as shown in the following formula (1).

[0073]

[0074] For each pixel (x, y) in the first image, the machine calculates the new position (x', y') after the rotation matrix R(θ), where x' = x * cosθ- y * sinθ and y' = x * sinθ + y * cosθ.

[0075] After determining the new position of each pixel after the transformation, create a new image data structure with the same size as the first image. Copy the color value or intensity value of the original pixel (x, y) to the new position (x', y'). If (x', y') is not an integer coordinate, it may be necessary to use image interpolation techniques (such as nearest neighbor interpolation, bilinear interpolation, or bicubic interpolation) to determine the pixel value of the new position. During the rotation transformation process, some areas of the new image may not have corresponding original pixels. These areas can be filled as needed, such as using black, white, or copying the values ​​of neighboring pixels. The machine creates a new image based on the rotated pixel position and the interpolated pixel value, which contains the rotated content. Through the above steps, a rotated third image can be obtained. In the third image, the edge lines in the extension direction of each film layer of the flexible screen are parallel to the first edge of the third image (usually the top or bottom edge of the image).

[0076] Based on the same method, the second image is rotated and transformed according to the second angle as follows: the second rotation matrix can be determined according to the second angle; the position of each pixel after the rotation transformation is determined according to the position of each pixel in the second image and the second rotation matrix; the fourth image is constructed according to the position of each pixel after the rotation transformation. The specific implementation can refer to the above-mentioned process of "rotating the first image according to the first angle", which will not be repeated here.

[0077] Secondly, according to the grayscale value of each row of pixels in the third image and the fourth image, the position of each film layer in the flexible screen in the third image and the fourth image is determined. Here, reference can be made to the above process of "determining the position of each film layer in the flexible screen in the first image and the second image according to the grayscale value of each row of pixels in the first image and the second image", which will not be repeated here.

[0078] Finally, according to the positions of the film layers in the flexible screen in the third image and the fourth image, the first position and the second position of the key point of each film layer in the flexible screen are determined. Here, reference can be made to the above process of "determining the first position and the second position of the key point of each film layer in the flexible screen according to the positions of each film layer in the flexible screen in the first image and the second image", which will not be repeated here.

[0079] Step S103: determining the displacement of each film layer during the bending process of the flexible screen according to the first position and the second position of the key point of each film layer in the flexible screen.

[0080] In a possible implementation, the absolute value of the difference between the first horizontal coordinate and the second horizontal coordinate of the key point of each film layer in the flexible screen can be determined as the displacement of each film layer during the bending process of the flexible screen based on the first horizontal coordinate of the first position and the second horizontal coordinate of the second position of the key point of each film layer.

[0081] In this embodiment, since the flexible screen undergoes horizontal displacement in the process of changing from the unfolded state to the non-expanded state, the ordinates of the key points of the film layers do not change, but the abscissas change. The absolute value of the difference between the first abscissa and the second abscissa of the key points of the film layers can be calculated and determined as the displacement of the film layers during the bending process of the flexible screen, and the calculation method is simple.

[0082] It is worth noting that if there are multiple second images, the displacement of each film layer during the bending process of the flexible screen is calculated for each second image. The specific implementation process is the same as the above process and will not be repeated here.

[0083] It should be understood that the above examples are intended to help those skilled in the art understand the embodiments of the present application, rather than to limit the embodiments of the present application to the specific numerical values ​​or specific scenarios illustrated. Those skilled in the art can obviously make various equivalent modifications or changes based on the above examples, and such modifications or changes also fall within the scope of the embodiments of the present application.

[0084] The present application also provides a flexible screen detection method. The following is a detailed description of the flexible screen detection method provided by the present application in conjunction with the accompanying drawings. Figure 6 The figure is an exemplary flow chart of a flexible screen detection method.

[0085] Step S301: using a camera to obtain a first image of the flexible screen in an unfolded state and a second image of the flexible screen in a non-expanded state.

[0086] Step S302: Determine the first position and the second position of the key point of each film layer in the flexible screen according to the first image and the second image.

[0087] Step S303: determining the displacement of each film layer during the bending process of the flexible screen according to the first position and the second position of the key point of each film layer in the flexible screen.

[0088] The above steps S301 to S303 are substantially the same as steps S101 to S103 in the above embodiment, and will not be described again in this embodiment to avoid repetition.

[0089] Step S304: Compare the displacement of each film layer during the bending process of the flexible screen with the preset displacement threshold of each film layer to determine whether the displacement of any film layer exceeds the corresponding preset displacement threshold. If the determination is yes, proceed to step S305; if the determination is no, proceed to step S306.

[0090] Step S305: Detection failure.

[0091] Step S306: Detection passed.

[0092] After determining the displacement of each film layer during the transformation of the flexible screen from the first image to the second image, the displacement of each film layer is compared with the preset displacement threshold of each film layer. If the displacement of any film layer exceeds its corresponding preset displacement threshold, it can be considered that the flexible screen will be delaminated after long-term use, which will lead to display problems such as black spots. Therefore, it is determined that the flexible screen fails the test. If the displacement of each film layer does not exceed its corresponding preset displacement threshold, it is determined that the flexible screen passes the test. The preset displacement threshold here can be determined by the designer according to actual needs.

[0093] It is achievable by testing the displacement of each film layer during the bending of flexible screens made of various different materials, as well as testing the displacement of each film layer during the bending of flexible screens using different types of glue as adhesives, and then guiding designers to select film layer materials and glue types based on the test results.

[0094] In one possible implementation, there are multiple second images, and the bending angles of the flexible screen in any two second images are different; the displacement of each film layer during the bending process of the flexible screen is determined according to the first position and the second position of the key points of each film layer in the flexible screen, including: for each second image, according to the first position and the second position of the key points of each film layer in the flexible screen, the displacement of each film layer in the process of transforming the flexible screen from the first image to the second image is determined; the maximum displacement of each film layer in the multiple second images is determined, and the maximum displacement of each film layer is determined as the displacement of each film layer during the bending process of the flexible screen.

[0095] Assume that there is a flexible screen with three second images, corresponding to different bending angles (for example, 30 degrees, 45 degrees, and 60 degrees). The position of the key point A of the display layer in the first image (unfolded state) is (x1, y1). The position of the key point A of the display layer in a second image (30-degree bending) becomes (x1`, y1`), and the displacement is Δx1 = x1` - x1. The position of the key point A of the display layer in another second image (45-degree bending) becomes (x1``, y1``). The displacement is Δx2 = x1`` -x1. The position of the key point A of the display layer in another second image (60-degree bending) becomes (x1```, y1```), and the displacement is Δx3 = x1``` - x1. For the key point A of the display layer, compare Δx1, Δx2, and Δx3 to find the maximum value. If Δx3 is the largest, Δx3 is determined as the displacement of the display layer.

[0096] In this embodiment, the maximum displacement of each film layer is compared with a preset displacement threshold of each film layer, thereby further ensuring the accuracy of detection.

[0097] Figure 7 4 is a schematic diagram of the structure of a detection device 400 provided in an embodiment of the present application, including an image acquisition module 401 and a processing module 402. The image acquisition module 401 is used to implement the relevant steps of "acquiring an image" in the displacement detection method, and the processing module 402 is used to implement the relevant steps of "determining the first position and the second displacement, and determining the displacement amount of each film layer" in the displacement detection method. For the sake of brevity, it will not be repeated here.

[0098] Alternatively, the image acquisition module 401 is used to implement the relevant steps of "acquiring an image" in the flexible screen detection method, and the processing module 402 is used to implement the relevant steps of "determining the first position and the second displacement, determining the displacement of each film layer, and judging whether the detection is qualified" in the flexible screen detection method. For the sake of brevity, it will not be repeated here. In this embodiment, the image acquisition module 401 can be the "camera" in the above embodiment.

[0099] The present application also provides a computer-readable storage medium, which stores a computer program. The computer program includes program instructions. When the program instructions are executed, the displacement detection method or flexible screen detection method provided in the embodiments of the present application is implemented.

[0100] The present application also provides a computer program product, which includes: computer program code, when the computer program code is run on a computer, the computer executes the displacement detection method or flexible screen detection method provided in the embodiments of the present application.

[0101] The above embodiments may be implemented in whole or in part by software, hardware, firmware or any other combination thereof. When implemented by software, the above embodiments may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded or executed on a computer, the process or function described in the embodiment of the present application is generated in whole or in part. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions may be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions may be transmitted from one website, computer, server or data center to another website, computer, server or data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium may be any available medium that a computer can access or a data storage device such as a server or data center that contains one or more available media sets. The available medium may be a magnetic medium (e.g., a floppy disk, a hard disk, a tape), an optical medium (e.g., a DVD), or a semiconductor medium. The semiconductor medium may be a solid state drive (SSD).

[0102] Those of ordinary skill in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the embodiments of the present application.

[0103] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0104] In the several embodiments provided in the embodiments of the present application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0105] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, and may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0106] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0107] If the function is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the embodiment of the present application is essentially or the part that contributes to the prior art or the part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions to enable a memory (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the method described in each embodiment of the embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (Read-Only Memory, ROM), random access memory (Random Access Memory, RAM), disk or optical disk and other media that can store program codes.

[0108] The above is only a specific implementation of the embodiment of the present application, but the protection scope of the embodiment of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or replacements within the technical scope disclosed in the embodiment of the present application, which should be included in the protection scope of the embodiment of the present application. Therefore, the protection scope of the embodiment of the present application should be based on the protection scope of the claims.

Claims

1. A displacement detection method, characterized in that: Applied to the detection of displacement of each film layer in a flexible screen, the method comprises: A first image of the flexible screen in an unfolded state and a second image in a non-expanded state are acquired by using a camera, wherein the flexible screen includes a first screen and a second screen, the non-expanded state is formed when the first screen remains stationary and the second screen is bent toward the first screen, the flexible screen includes a first side surface, the first side surface is a side surface of the first screen, the first side surface is perpendicular to a bending line of the flexible screen, the first image and the second image both include the first side surface, and the first side surface includes each film layer of the flexible screen; when the camera acquires the first image and the second image, the vertical distance from the first side surface is the same, the height of the camera remains unchanged, and the camera and the side surface of the first screen remain in a relatively horizontal state; Determine, according to the first image and the second image, a first position and a second position of a key point of each film layer in the flexible screen, wherein the key point is a protruding point and / or a recessed point formed in the process of preparing the flexible screen, or the key point is an identification point formed in each film layer of the flexible screen after the flexible screen is prepared; the first position is a position of the key point of each film layer in the first image, and the second position is a position of the key point of each film layer in the second image; Determine a first horizontal coordinate of the first position of the key point of each film layer in the flexible screen, and a second horizontal coordinate of the second position; The absolute value of the difference between the first horizontal coordinate and the second horizontal coordinate of the key point of each film layer is determined as the displacement of each film layer during the bending process of the flexible screen.

2. The displacement detection method according to claim 1, characterized in that: Determining the first position and the second position of the key point of each film layer in the flexible screen according to the first image and the second image includes: Determine the position of each film layer in the flexible screen in the first image and the second image according to the grayscale value of each row of pixels in the first image and the second image; According to the positions of the film layers in the flexible screen in the first image and the second image, the first positions and the second positions of the key points of the film layers in the flexible screen are determined.

3. The displacement detection method according to claim 2, characterized in that: The key points are convex points and / or concave points formed during the preparation process of the flexible screen; The determining, according to the positions of the film layers in the flexible screen in the first image and the second image, the first position and the second position of the key point of each film layer in the flexible screen comprises: Determine first characteristic information and first positions of all raised points and / or sunken points of each film layer in the first image according to the positions of each film layer in the flexible screen in the first image; Determine second characteristic information and second positions of all raised points and / or sunken points of each film layer in the second image according to the positions of each film layer in the flexible screen in the second image; Determine the convex point / concave point in each film layer where the first characteristic information and the second characteristic information are the same as the key point; The first position and the second position of the key point in each film layer are determined.

4. The displacement detection method according to claim 2, characterized in that: The key points are convex points and / or concave points formed during the preparation process of the flexible screen; The determining, according to the positions of the film layers in the flexible screen in the first image and the second image, the first position and the second position of the key point of each film layer in the flexible screen comprises: Determine first characteristic information and first positions of the protruding points / depressed points of each film layer in the first image according to the positions of each film layer in the flexible screen in the first image; Determine the convex points / concave points of each film layer in the first image as the key points of each film layer; According to the first feature information of the key points of each film layer and the position of each film layer in the flexible screen in the second image, the second position of the key points of each film layer in the second image is determined.

5. The displacement detection method according to claim 1, characterized in that: Determining the first position and the second position of the key point of each film layer in the flexible screen according to the first image and the second image includes: Determine a third image according to the first image, and determine a fourth image according to the second image, wherein the extension direction of each film layer of the flexible screen in the third image and the fourth image is parallel to the horizontal direction; Determine the position of each film layer in the flexible screen in the third image and the fourth image according to the grayscale value of each row of pixels in the third image and the fourth image; According to the positions of the film layers in the flexible screen in the third image and the fourth image, the first position and the second position of the key point of each film layer in the flexible screen are determined.

6. The displacement detection method according to claim 1, characterized in that: There are multiple second images, and the bending angles of the flexible screen in any two of the second images are different.

7. A flexible screen detection method, characterized in that: include: The method comprises: A first image of the flexible screen in an unfolded state and a second image in a non-expanded state are acquired by using a camera, wherein the flexible screen includes a first screen and a second screen, the non-expanded state is formed when the first screen remains stationary and the second screen is bent toward the first screen, the flexible screen includes a first side surface, the first side surface is a side surface of the first screen, the first side surface is perpendicular to a bending line of the flexible screen, the first image and the second image both include the first side surface, and the first side surface includes each film layer of the flexible screen; when the camera acquires the first image and the second image, the vertical distance from the first side surface is the same, the height of the camera remains unchanged, and the camera and the side surface of the first screen remain in a relatively horizontal state; Determine, according to the first image and the second image, a first position and a second position of a key point of each film layer in the flexible screen, wherein the key point is a protruding point and / or a recessed point formed in the process of preparing the flexible screen, or the key point is an identification point formed in each film layer of the flexible screen after the flexible screen is prepared; the first position is a position of the key point of each film layer in the first image, and the second position is a position of the key point of each film layer in the second image; determining, according to the first position and the second position of the key point of each film layer in the flexible screen, a displacement of each film layer during a bending process of the flexible screen; The method of determining the displacement of each film layer during the bending process of the flexible screen according to the first position and the second position of the key point of each film layer in the flexible screen comprises: determining the first horizontal coordinate of the first position of the key point of each film layer in the flexible screen and the second horizontal coordinate of the second position; and determining the absolute value of the difference between the first horizontal coordinate and the second horizontal coordinate of the key point of each film layer as the displacement of each film layer during the bending process of the flexible screen; The displacement of each film layer during the bending process of the flexible screen is compared with the preset displacement threshold of each film layer. If the displacement of any film layer exceeds the corresponding preset displacement threshold, the test fails; if the displacement of any film layer does not exceed the corresponding preset displacement threshold, the test passes.

8. The flexible screen detection method according to claim 7, characterized in that: There are multiple second images, and the bending angles of the flexible screen in any two of the second images are different; The determining, according to the first position and the second position of the key point of each film layer in the flexible screen, the displacement of each film layer during the bending process of the flexible screen includes: For each of the second images, determining the displacement of each film layer in the flexible screen during the transformation from the first image to the second image according to the first position and the second position of the key point of each film layer in the flexible screen; The maximum value of the displacement of each film layer in the plurality of second images is determined, and the maximum value of the displacement of each film layer is determined as the displacement of each film layer during the bending process of the flexible screen.

9. A detection device, characterized in that: The device includes a memory and a processor, the memory is used to store instructions, and when the instructions are executed by the processor, the detection device executes the displacement detection method as described in any one of claims 1 to 6, or executes the flexible screen detection method as described in claim 7 or 8.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, which includes program instructions. When the program instructions are executed, the displacement detection method according to any one of claims 1 to 6 is implemented, or the flexible screen detection method according to claim 7 or 8 is implemented.

11. A computer program product, characterized in that The computer program product comprises: a computer program code, which, when executed on a computer, enables the computer to execute the displacement detection method according to any one of claims 1 to 6, or the flexible screen detection method according to claim 7 or 8.

Images